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In this study, the feasibility of mini-light-emitting diode (LED) RGB display fabricated by a chip-first fan-out panel-level packaging is investigated. Emphasis is placed on the design, materials, process, fabrication, and reliability of the mini-LED RGB display package on a printed circuit board (PCB). The mini-LEDs under consideration and their sizes are red ( $125 \times 250 \times 100 ~\mu \text{m}$ ), green ( $130 \times 270 \times 100 ~\mu \text{m}$ ), and blue ( $130 \times 270 \times 100 ~\mu \text{m}$ ). The spacing among the RGB mini-LEDs is $80~\mu \text{m}$ , the pixel-to-pixel spacing is also $\sim 80~\mu \text{m}$ , and the pixel pitch is $625~\mu \text{m}$ . The temporary glass panel for making the redistribution layers (RDLs) of the package is $515 \times 510 \times 1.1$ mm in size. To increase the SMT assembly yield on the PCB, the mini-LEDs are grouped into 4( $2 \times 2$ pixels)-in-one surface mount device (SMD), that is, a total of 12 R, B, and G mini-LEDs. A PCB ( $132\,\,mm \times 77$ mm) is designed and fabricated for the drop test of the mini-LED package. Thermal cycling of the mini-LED SMD PCB assembly is also performed by a nonlinear temperature- and time-dependent finite-element simulation.

This article presents a prototype $22.4~\mu \text{m}$ pixel pitch global shutter (GS) wide dynamic range (WDR) soft X-ray CMOS image sensor (sxCMOS). Backside-illuminated (BSI) pinned photodiodes with a 45- $\mu \text{m}$ thick Si substrate were introduced for low noise and high radiation hardness to high energy photons. Two-stage lateral overflow integration capacitor (LOFIC) and voltage domain memory bank with high-density Si trench capacitors were introduced for WDR and for GS. The developed sxCMOS achieved maximum 21.9 Me− full well capacity with a single exposure 129 dB dynamic range by GS operation. Over 70% quantum efficiency (QE) toward soft X-ray was successfully achieved. The developed prototype sxCMOS is a step forward toward a 4 M pixel detector system to be utilized in next-generation synchrotron radiation facilities and X-ray free-electron lasers.

We report on the design and characterization of a monolithic single-photon-counting (SPC) X-ray detector integrating an amorphous semiconductor sensor. Our prototype combines amorphous selenium (a-Se), a well-known photoconductor, with a CMOS readout integrated circuit (ROIC) containing two $26\times196$ arrays of single-energy-threshold pixels. We achieve high spatial resolution for capturing single 60-keV photons by implementing 11.4- $\mu \text{m}$ -pitch pixels and by integrating a 70- $\mu \text{m}$ -thick a-Se sensor on the ROIC. We present experimental SPC results using a mono-energetic 60-keV radioactive source. Our results also suggest that our prototype a-Se/CMOS detector leverages the small-pixel effect (SPE) due to the large ratio of a-Se thickness to pixel pitch. This effect could overcome the slow inherent transient response of a-Se for high count rate X-ray diagnostic applications like mammography.

Currently, we are developing a neutron scintillation detector prototype using silicon photomultipliers (SiPMs) as the photodetector. In order to reconstruct the position of single neutron events to an accuracy better than the pixel pitch of the SiPM, a very accurate photon count is required. Each pixel consists of 3200 microcells, operated in Geiger mode. A cell which is already triggered cannot detect any following photons hitting the cell, until it is recharged. This leads to a nonlinearity in the pixel’s response for a higher photon density impinging across the pixel. Previous studies provided a correction factor to estimate the saturation, by assuming a homogeneous photon distribution density and comparing it to the number of microcells. In our specific application, the photon distribution is not homogeneous, which is why we examined the influence of the homogeneity on the saturation. In this work, we present a case study for difference in nonlinearity effect for an inhomogeneous and homogeneous photon distribution density, given the light intensity is equal. The simulation results suggest that the effect could be higher for an inhomogeneous distribution. Therefore, care must be taken when using the established correction factor for saturation and an analysis of the photon distribution homogeneity is necessary.

CMOS image sensor’s ability to collect light depends, amongst others, on its full well capacity (FWC) which is the capability of a pixel of storing electrons. The FWC can be improved either by expensive and time-consuming process modifications or by increasing the pixel photodiode area. Optimizing the pixel layout is crucial to increase the photodiode area at a given pixel pitch. In this article, we present a novel layout technique that reduces the area occupied by the in-pixel transistors by reorganizing the shared diffusions. Such optimization is demonstrated to increase the area of the photodiode for a given pixel pitch and, hence, the fill factor (FF). Both a mathematical model of the methodology and experimental results of pixels manufactured in a commercially available technology are presented. We prove that the technique is particularly effective for small pixel pitches and can lead to an increase in FF and FWC of at least 20% in a 4-transistor CMOS pixel with 2.4- $\mu \text{m}$ pitch.

The X-ray free-electron lasers that became available during the last decade, like the European XFEL (EuXFEL), place high demands on their instrumentation. Especially at low photon energies below $1\,\text{keV}$, detectors with high sensitivity, and consequently low noise and high quantum efficiency, are required to enable facility users to fully exploit the scientific potential of the photon source. A 1-Megapixel pnCCD detector with a $1024\times 1024$ pixel format has been installed and commissioned for imaging applications at the Nano-Sized Quantum System (NQS) station of the Small Quantum System (SQS) instrument at EuXFEL. The instrument is currently operating in the energy range between $0.5$ and $3\,\text{keV}$ and the NQS station is designed for investigations of the interaction of intense FEL pulses with clusters, nano-particles and small bio-molecules, by combining photo-ion and photo-electron spectroscopy with coherent diffraction imaging techniques. The core of the imaging detector is a pn-type charge coupled device (pnCCD) with a pixel pitch of $75\,\mu\text{m}\times 75\,\mu\text{m}$. Depending on the experimental scenario, the pnCCD enables imaging of single photons thanks to its very low electronic noise of $3$e$^-$ and high quantum efficiency. Here we present an overview on the EuXFEL pnCCD detector and the results from the commissioning and first user operation at the SQS experiment in June 2019. The detailed descriptions of the detector design and capabilities, its implementation at EuXFEL both mechanically and from the controls side as well as important data correction steps aim to provide useful background for users planning and analyzing experiments at EuXFEL and may serve as a benchmark for comparing and planning future endstations at other FELs., Comment: 10 pages, 10 figures, submitted to the Journal of Synchrotron Radiation

We present a monolithic hybrid visible-light imager composed of an amorphous selenium (a-Se) photoconductor thin film integrated on a CMOS active pixel sensor (APS) array readout integrated circuit. We achieve more than 14-dB signal-to-noise ratio under monochromatic light at an illuminance of 0.04 lux in one quadrant of the imager containing $7.8\times 7.8-\mu \,\,\text{m}^{2}$ pixels using a 1.6-s exposure (integration) time without operating the a-Se sensor in avalanche mode. Long integration times are made possible by exploiting the low dark-current of a 20- $\mu \text{m}$ -thick a-Se sensor layer and by implementing dark-current reduction techniques in the APS, such as series stacking reset and protection devices. In addition, use of a relatively thick 20- $\mu \text{m}$ a-Se layer obviates the need for an additional planarization step of the sensing layer as was done with a previously-reported avalanche-mode a-Se/CMOS imager that incorporated a 0.5- $\mu \text{m}$ -thick sensing layer. We also demonstrate an improved APS design, with $7.8\times 8.7-\mu \,\,\text{m}^{2}$ dimensions, containing a programmable in-pixel integration capacitor to provide enhanced full-well capacity (FWC) for a-Se/CMOS imagers. Measured results show that our APS achieves a FWC of approximately 230 ke−, which is comparable to several previously-reported photodiode-based CMOS imagers with extended FWC. Our imager can also resolve an effective object size of approximately $12.5~\mu \text{m}$ , demonstrated through measurement of the modulation transfer function.

Holography is a promising technology for photo-realistic three-dimensional (3D) displays because of its ability to replay the light reflected from an object using a spatial light modulator (SLM). However, the enormous computational requirements for calculating computer-generated holograms (CGHs)—which are displayed on an SLM as a diffraction pattern—are a significant problem for practical uses (e.g., for interactive 3D displays for remote navigation systems). Here, we demonstrate an interactive 3D display system using electro-holography that can operate with a consumer’s CPU. The proposed system integrates an efficient and fast CGH computation algorithm for line-drawn 3D objects with inter-frame differencing, so that the trajectory of a line-drawn object that is handwritten on a drawing tablet can be played back interactively using only the CPU. In this system, we used an SLM with 1,920 $$\times $$ × 1,080 pixels and a pixel pitch of 8 μm × 8 μm, a drawing tablet as an interface, and an Intel Core i9–9900K 3.60 GHz CPU. Numerical and optical experiments using a dataset of handwritten inputs show that the proposed system is capable of reproducing handwritten 3D images in real time with sufficient interactivity and image quality.

Flexible printed circuit boards (FPCB) are widely used in smart devices with high wiring density and light weight. In this paper, the chemical etching process of FPCB with 18 $\mu \text{m}$ line pitch is investigated. A geometric model of the FPCB circuit with the shape of “T” is established and simulated by the finite element method. The time evolution of the etching cavity, concentration field and velocity field of CuCl2 solution are studied, as well as the effects of initial concentrations and inlet velocities on the etching cavity profile. Finally, the FPCB sample with 18 $\mu \text{m}$ line pitch is successfully fabricated by employing process parameters from the etching simulation. The results show that as the increase in the etching cavity, recirculating eddies form at the bottom of the photoresist in the corners of the etching cavity, resulting in more etching on the top sides of sidewalls over time. Higher initial concentration of the etching solution will result in a larger etching cavity profile, but the inlet velocity cannot affect the etching cavity profile significantly. Finally, the effectiveness of the simulation model is verified by comparing the etching cavity profiles with four experiments.

Proximity charge sensing is a novel technique used in the field of radiation detection. This research examines the simulation of a pixelated anode proximity charge-sensing device on CZT semiconductors to evaluate the potential performance of the proximity sensing technique on room-temperature detector materials for imaging purposes. The weighting potentials (WPs), of proximity-sensing and directly deposited electrode pixelated designs, were generated using ANSYS Maxwell, and the best design will be considered for the implementation step in the future. The simulation investigated two features of the proximity design, pixel size and pixel pitch. Three different pixel sizes were used in the simulation designs, 0.5 × 0.5 mm2, 1.0 × 1.0 mm2, and 2.0 × 2.0 mm2. The 0.5 × 0.5 mm2 pixel size had the best WP profile, where the generated signal for one radiation energy did not depend on the interaction location. Pixel pitch was examined using the same pixel size, 1.0 × 1.0 mm2, and varying the pixel pitch from 2.0 mm, 3.0 mm up to 4.0 mm. The results showed that as the pixel pitch increases, the signal crosstalk (charge sharing between pixels) decreases. However, as the pixel pitch increases, the spatial resolution of the imaging system decreases, making it difficult to observe objects smaller in diameter than the pixel pitch. Additionally, proximity charge sensing designs showed better performance in terms of signal crosstalk for the same pixel size and pixel pitch in comparison with directly deposited designs.

Experimental assessment of small pitch cooled infrared focal plane arrays (FPA) modulation transfer function (MTF) is becoming an important issue. Indeed, the pitch approaches the typical carrier diffusion length of minority carriers in the absorber material. Therefore, the MTF is an important figure of merit of those arrays as it may be degraded by lateral diffusion. Moreover, the pitch also approaches the sensed wavelength so direct MTF measurement using optical projections becomes difficult. In this paper, we propose the use of electron beam induced current to experimentally characterize the MTF of small pitch cooled FPAs. Practically, the device is mounted inside a scanning electron microscope onto a cooled sample stage. The diode area is then scanned by the electron beam instead of the optical beam in classical MTF measurement. Because of the very narrow electron beam, the MTF can then be estimated with an excellent precision. First scans of mid-wave 7.5 μm pitch HgCdTe diodes are shown, demonstrating a 55% MTF at the Nyquist frequency, consistent with 3D electro-optical modeling. The relevance of this estimation is also discussed, in comparison with classical projection methods.

We have developed and demonstrated an image super-resolution method—XR-UNLOC: X-Ray UNsupervised particle LOCalization—for hard x-rays measured with fast-frame-rate detectors that is an adaptation of the principle of photo-activated localization microscopy (PALM) and stochastic optical reconstruction microscopy (STORM), which enabled biological fluorescence imaging at sub-optical-wavelength scales. We demonstrate the approach on experimental coherent Bragg diffraction data measured with 52 keV x-rays from a nanocrystalline sample. From this sample, we resolve the fine fringe detail of a high-energy x-ray Bragg coherent diffraction pattern to an upsampling factor of 16 of the native pixel pitch of 30 μm of a charge-integrating fastCCD detector. This was accomplished by analysis of individual photon locations in a series of “nearly-dark” instances of the diffraction pattern that each contain only a handful of photons. Central to our approach was the adaptation of the UNLOC photon fitting routine for PALM/STORM to the hard x-ray regime to handle much smaller point spread functions, which required a different statistical test for photon detection and for sub-pixel localization. A comparison to a photon-localization strategy used in the x-ray community (“droplet analysis”) showed that XR-UNLOC provides significant improvement in super-resolution. We also developed a metric by which to estimate the limit of reliable upsampling with XR-UNLOC under a given set of experimental conditions in terms of the signal-to-noise ratio of a photon detection event and the size of the point spread function for guiding future x-ray experiments in many disciplines where detector pixelation limits must be overcome.

International audience; Infrared cameras could serve automotive applications by delivering breakthrough perception systems for both in-cabin passengers monitoring and car surrounding. However, low-cost and high-throughput manufacturing methods are essential to sustain the growth in thermal imaging markets for automotive applications, and for other close-to-consumer applications which have a fast growth potential. Fast low cost infrared lenses suitable for microbolometers are currently already sold by companies like Umicore, Lightpath, FLIR… They are either made of a single inverse meniscus Chalcogenide glass or of two Silicon optics. In this paper, we explore hybrid systems with a large field of view around 40° combining Chalcogenide and Silicon in order to take advantage of both materials. Both are compatible with wafer-level process. Silicon optics can be manufactured by photolithography process and are expected to be more cost-effective than Chalcogenide ones. However they are constrained in shape and sag height. On the other hand, Chalcogenide optics can be collectively molded and could have more free shapes. They are thus more suitable to reach high-demanding performance. So hybrid designs could be seen as a compromise between cost and performance. In this paper, we show that fast lenses with diameter constraints to few millimeters to make affordable wafer-level process lead to small size detectors. As a consequence, the pixel pitch reduction of microbolometers is a key point to maintain a good resolution. Finally, strategies to improve the production yield of hybrid lenses are explored.

Due to the large pixel pitch and limited size of spatial light modulator (SLM), the field of view (FOV) of current holographic display is greatly restricted. Cylindrical holography can effectively overcome the constraints of FOV. However, the existent algorithms of cylindrical hologram are all based on the wave-optics based approach. In this paper, to the best of our knowledge, we adopt the ray-optics based approach in the generation of cylindrical computer generated hologram (CCGH) for the first time. Information of parallax images captured from three-dimensional (3D) objects using a curved camera array is recorded into a cylindrical hologram. Two different recording specific algorithms are proposed, one is based on the Fast Fourier Transform (FFT) method, and another is based on the pinhole-type integral imaging (PII) method. The simulation results confirm that our proposed methods are able to realize a fast generation of the cylindrical photorealistic hologram.

Pixelated silicon detectors are state-of-the-art technology to achieve precise tracking and vertexing at collider experiments, designed to accurately measure the hit position of incoming particles in high rate and radiation environments. The detector requirements become extremely demanding for operation at the High-Luminosity LHC, where up to 200 interactions will overlap in the same bunch crossing on top of the process of interest. Additionally, fluences up to 2.3 × 1016 cm−2 1 MeV neutron equivalent at 3.0 cm distance from the beam are expected for an integrated luminosity of 3000 fb−1. In the last decades, the pixel pitch has constantly been reduced to cope with the experiments’ needs of achieving higher position resolution and maintaining low pixel occupancy per channel. The spatial resolution improves with a decreased pixel size but it degrades with radiation damage. Therefore, prototype sensor modules for the upgrade of the experiments at the HL-LHC need to be tested after being irradiated. This paper describes position resolution measurements on planar prototype sensors with 100 × 25 µm2 pixels for the CMS Phase-2 Upgrade. It reviews the dependence of the position resolution on the relative inclination angle between the incoming particle trajectory and the sensor, the charge threshold applied by the readout chip and the bias voltage. A precision setup with three parallel planes of sensors has been used to investigate the performance of sensors irradiated to fluences up to ϕ eq = 3 . 6 × 1 0 15 cm−2. The measurements were performed with a 5 GeV electron beam. A spatial resolution of 3 . 2 ± 0.1 µm is found for non-irradiated sensors, at the optimal angle for charge sharing. The resolution is 5 . 0 ± 0.2 µm for a proton-irradiated sensor at ϕ eq = 2 . 1 × 1 0 15 cm−2 and a neutron-irradiated sensor at ϕ eq = 3 . 6 × 1 0 15 cm−2. The extrapolated resolution to infinite beam momentum, where the contribution of multiple scattering can be neglected, has also been evaluated.

To achieve a resolving power greater than 100 000, we are developing a superconducting nanostrip single photon detector (SSPD) for an ultrahigh-resolution RIXS spectrometer in the Taiwan Photon Source. To achieve the target resolving power, the SSPD, combined with a microstripline (MSL) structure, which acts as a delay line, should have a line pitch of 0.5 μm. This study uses numerical simulations to design SSPD. It consists of a meander of a 50-nm-thick Nb nanostrip and a 45-nm-thick SiO2 underlayer. The width of the line and the gap of the meander are 400 and 100 nm, respectively. The estimated velocity of the transmitted pulses due to X-ray absorption in the Nb nanostrip of the above SSPD is ~5% of the speed of light in free space. A detection area of 16 mm × 5 mm is sufficient to allow a time difference of ~1 ns between neighboring nanostrips to be distinguishable using conventional time to digital converters (TDCs). We fabricated a trial SSPD imager with dimensions of 4 mm × 0.1215 mm, and measured signal pulse characteristics for ions simulating soft X-ray photons. During an experiment, the maximum time difference of 7.5 ns between output pulses from both ends of the nanostrip successfully exhibited the proper imaging operation.

A single-projection based phase retrieval method based on the phase attenuation duality principle (PAD) was used to compare the spatial resolution of the acquired phase sensitive and PAD processed phase retrieved images. An inline phase sensitive prototype was used to acquire the phase sensitive images. The prototype incorporates a micro-focus x-ray source and a flat panel detector with a 50 μm pixel pitch. A phantom composed of a 2 cm thick 50-50 adipose-glandular mimicking slab sandwiched with a 0.82 cm thick slanted PMMA sharp edge was used. Phase sensitive image of the phantom was acquired at 120 kV, 3.35 mAs with a 16 μm tube focal spot size under a geometric magnification (M) of 2.5. The PAD based method was applied to the acquired phase sensitive image for the retrieval of phase values. With necessary data processing, modulation transfer function (MTF) curves were determined for the estimation and comparison of the spatial resolution. The PAD processed phase retrieved values of the phantom were in good agreement with the theoretically calculated values. Phase sensitive images showed higher spatial resolution at all spatial frequencies compared to the phase retrieved images. It was noted that the high-frequency signal components in the retrieved image were suppressed that resulted in lower MTF values. When compared to the phase sensitive image, the cutoff resolution (10% MTF) for phase retrieved image dropped 32% from 15.6 lp/mm (32μm) to 10.6 lp/mm (47μm). The resolution offered by this phase sensitive prototype is radiographically enough to detect breast cancer.

The Circular Electron Positron Collider (CEPC) is proposed as a Higgs factory for precision measurement of properties of the Higgs boson. The CEPC vertex detector requires low material budget, high spatial resolution, fast readout and low power consumption. Monolithic Active Pixel Sensor (MAPS), as one of the promising candidate technologies, has been studied within the R&D activities for the CEPC vertex detector. This proceeding introduces recent development of a MAPS prototype using the TowerJazz 180 nm CMOS Image Sensor process. Two different binary front-end circuits have been designed to explore an in-pixel front-end structure suitable for a compact pixel in combination with an in-matrix sparsified readout circuitry. To achieve high granularity together with fast readout speed, a new architecture of asynchronous data-driven matrix readout has been implemented. The prototype contains 128 rows and 64 columns featuring a small pixel pitch of 25 μ m . The address of one hit pixel can be read out in 25 ns. This work presents the design of the prototype, which is currently under test.

We present the analysis of data taken by the Space Application of Timepix Radiation Monitor (SATRAM). It is centred on a Timepix detector (300 μ m thick silicon sensor, pixel pitch 55 μ m, 256 × 256 pixels). It was flown on Proba-V, an Earth observing satellite of the European Space Agency (ESA) from an altitude of 820 km on a sun-synchronous orbit, launched on May 7, 2013. A Monte Carlo simulation was conducted to determine the detector response to electrons (0.5–7 MeV) and protons (10–400 MeV) in an omnidirectional field taking into account the shielding of the detector housing and the satellite. With the help of the simulation, a strategy was developed to separate electrons, protons and ions in the data. The measured dose rate and stopping power distribution are presented as well as SATRAM’s capability to measure some of the stronger events in Earth’s magnetosphere. The stopping power, the cluster height and the shape of the particle tracks in the sensor were used to separate electrons, protons and ions. The results are presented as well. Finally, the pitch angles for a short period of time were extracted from the data and corrected with the angular response determined by the simulation.

We demonstrate how the latest generation of hybrid pixel detectors of the Timepix family can be used to reconstruct 3 dimensional particle tracks on a microscopic scale, additionally determining the stopping power along the particles’ paths. In an experiment, a Timepix3 detector with a 2 mm thick planar CdTe sensor was irradiated in a 40 GeV/c pion beam and used in a similar way to a time-projection chamber: The coordinates x and y were given by the trajectory projection (pixel pitch: $$55\,\upmu \hbox {m}$$ ), the z-coordinate was reconstructed from the charge carrier drift time measurement (time binning: 1.5625 ns). The achievable z-resolution was studied at different bias voltages. Systematic inaccuracies due to an imprecise drift time model were determined and separated from the intrinsic uncertainty given by the time resolution. It was shown that a z-resolution of $$60\,\upmu \hbox {m}$$ could be achieved by a perfect modeling of the drift time. With the presented z-reconstruction methodology, we studied the charge collection efficiency as a function of interaction depth, which was then used to apply a charge loss correction to the per-pixel energy measurements. 3D event displays of pion, muon and electron tracks are shown.

A novel approach for developing a large area, high-spatial-resolution X-ray imaging detector is presented. This approach uses metal–organic vapor phase epitaxy grown thick single-crystal CdTe layers grown directly on Si substrates. The detector consists of a p-CdTe/n-CdTe/n+-Si heterojunction diode structure, where the n-CdTe and the p-CdTe layers are successively grown on the n+-Si substrate. An array of ( $128\times128$ ) pixels was formed on the p-CdTe side, where each pixel is $60~\mu \text{m}^{\textsf {2}}$ in an 80- $\mu \text{m}$ pixel pitch. The detector array was bump bonded to a charge integration-type CMOS readout ASIC. The basic performance of this detector was evaluated by measuring the dark currents, the X-ray generation currents as well as taking the X-ray images of some objects. The results were promising which confirmed that the detector developed can be applied in high spatial resolution X-ray imaging.

Polarization sensitive quantum well infrared photodetector (QWIP) focal plane arrays (FPAs) with 30 and 15 µm pitch sizes are fabricated with wire grid polarizers monolithically integrated on the pixels. High polarization contrast is achieved for pixels with 30 µm pitch size, 0.58 ± 0.05 depending on the grating orientation, with good spatial homogeneity (standard deviation below 0.01). The polarization contrast drops to 0.30 ± 0.05 for 15 µm pixel pitch. Influence of the grating orientation on the optical responsivity and the polarization contrast has been evaluated showing the strongest impact for +45° orientations. The fabricated FPAs exhibit temporal and spatial Noise Equivalent (NE) Degree of Linear Polarization (DoLP) of 0.03% and 0.23%, respectively, setting the resolution limit of DoLP to 0.4%. Capability of the fabricated FPAs to image polarimetric signatures in the dynamic scenes with high frame rate has been demonstrated.

Cadmium zinc telluride (CdZnTe) detectors are known to suffer from polarization effects under high photon flux due to poor hole transport in the crystal material. This has led to the development of a high-flux capable CdZnTe material (HF-CdZnTe). Detectors with the HF-CdZnTe material have shown promising results at mitigating the onset of the polarization phenomenon, likely linked to improved crystal quality and hole carrier transport. Better hole transport will have an impact on charge collection, particularly in pixelated detector designs and thick sensors (&gt, 1 mm). In this paper, the presence of charge sharing and the magnitude of charge loss were calculated for a 2 mm thick pixelated HF-CdZnTe detector with 250 μm pixel pitch and 25 μm pixel gaps, bonded to the STFC HEXITEC ASIC. Results are compared with a CdTe detector as a reference point and supported with simulations from a Monte-Carlo detector model. Charge sharing events showed minimal charge loss in the HF-CdZnTe, resulting in a spectral resolution of 1.63 ± 0.08 keV Full Width at Half Maximum (FWHM) for bipixel charge sharing events at 59.5 keV. Depth of interaction effects were shown to influence charge loss in shared events. The performance is discussed in relation to the improved hole transport of HF-CdZnTe and comparison with simulated results provided evidence of a uniform electric field.

Low-Gain Avalanche Diodes are a recently-developed class of silicon sensors. Characterized by an internal moderate gain that enhances the signal amplitude and if built on thin silicon substrates of a few tens of microns, they feature fast signals and exhibit excellent timing performance. Thanks to their fast timing they are planned to be exploited in timing detectors in High-Energy Physics experiments, for example for the upgrades of the ATLAS and CMS detectors at the High Luminosity Large Hadron Collider (HL-LHC) at CERN. However, to achieve a spatially uniform multiplication a large pixel pitch is needed, preventing a fine spatial resolution. To overcome this limitation, the AC-coupled LGAD approach was introduced. In this type of device, metal electrodes are placed over an insulator at a fine pitch, and signals are capacitively induced on these electrodes. The fabrication technology is similar for the two LGAD families, although a fine tuning of a few process parameters needs to be carefully studied. Other R&D efforts towards detectors that can simultaneously provide good time and spatial resolution, based on the LGAD concept, are under way. These efforts aim also to mitigate the loss of performance at high irradiation fluences due to the acceptor removal within the gain layer. In this paper we describe the main points in the fabrication of LGADs and AC-LGADs in a clean-room. We also discuss novel efforts carried on related topics.

In a digital hologram, the maximum viewing angle of a computer-generated hologram (CGH) is limited by pixel pitch due to the diffraction grating equation. Since reducing pixel size of display panel is challenging and costly, we propose a method to expand the viewing angle of a digital hologram by attaching an aligned pixelated random phase mask (PRPM) onto the CGH pattern based on analysis of simulation results. By introducing a phase-averaging process to the widely used iterative Fourier transform algorithm, an optimized CGH pattern can be obtained in conjunction with a PRPM. Based on scalar diffraction theory, viewing angle enhancement characteristics were verified by comparing the perspective views of a two-plane hologram using a virtual eye model. In addition, we performed full electromagnetic simulations that included effects due to potential fabrication errors such as misalignment, thickness variation, and internal reflections and diffractions between the CGH and random mask patterns. From the simulation results, by attaching a 1.85 µm-sized pixel pitch PRPM to a 3.7 µm CGH, the viewing angle can be easily expanded almost identical to that of a CGH with 1.85 µm-pixel pitch.

For years, there has been a strong drive for sub-micron pixel development, in spite of reaching the visible light diffraction limit, because a smaller pixel pitch of CMOS image sensors (CISs) is inevitably required for ever-miniaturizing camera modules as mobile devices incorporate more cameras, few of which are dedicated to ultra-high-resolution zoomed images [1]. To that end, image sensor vendors have tried to find new ways to avoid reduction in sensitivity and more crosstalk in the sensor through pixel architecture change and/or fabrication process refinement [2] –[4]. For example, a $0.7 \mu m$ pixel sensor was demonstrated with acceptable photodiode (PD) full-well capacity (FWC) of $\gt 6$,000e- as well as signal-to-noise ratio (SNR) of $\sim32$ dB without optical/electrical crosstalk by employing state-of-the-art full-depth deep-trench isolations (FDTIs). [4] However, further scaling requires elaborate fabrication innovation and layout ideas. At the same time, meeting every aspect of pixel performance compared to the previous generation becomes even more difficult, e.g., with respect to dark or illuminated characteristics, fixed-pattern or temporal noises, etc. The latter, in particular, is associated with in-pixel source-follower (SF) amplifiers. Therefore, electrical performance of scaled in-pixel transistors cannot be overlooked. In this paper, a 32-megpixel (MP) CIS with $0.64 \mu m$ unit pixels is demonstrated with FDTI design. Innovations in terms of fabrication and design to achieve this performance with scaling are discussed.

Owing to the characteristics of existing spatial light modulators (SLMs), the computer-generated hologram (CGH) with continuous complex-amplitude is conventionally converted to a quantized amplitude-only or phase-only CGH in practical applications. The quantization of CGH significantly affects the holographic reconstruction quality. In this work, we evaluated the influence of the quantization for both amplitude and phase on the quality of holographic reconstructions by traversing method. Furthermore, we considered several critical CGH parameters, including resolution, zero-padding size, reconstruction distance, wavelength, random phase, pixel pitch, bit depth, phase modulation deviation, and filling factor. Based on evaluations, the optimal quantization for both available and future SLM devices is suggested.

The radiation hardness of passive CMOS pixel sensors fabricated in 150 nm LFoundry technology is investigated. CMOS process lines are especially of interest for large-scale silicon detectors as they offer high production throughput at comparatively low cost. Moreover, several features like poly-silicon resistors, MIM-capacitors and several metal layers are available which can help enhance the sensor design. The performance of a 100 $\mathrm{\mu}$m thin passive CMOS sensor with a pixel pitch of 50 $\mathrm{\mu}$m at different irradiation levels, 5 $\times$ 10$^{15}$n$_{\mathrm{eq}}$cm$^{-2}$ and 1 $\times$ 10$^{16}$n$_{\mathrm{eq}}$cm$^{-2}$, is presented. The sensor was bump-bonded and read out using the RD53A readout chip. After the highest fluence a hit-detection efficiency larger than 99% is measured for minimum ionising particles. The measured equivalent noise charge is comparable to conventional planar pixel sensors. Passive CMOS sensors are thus an attractive option for silicon detectors operating in radiation harsh environments like the upgrades for the LHC experiments., Comment: 18 pages, 10 figures

This paper proposes a 14-bit fully differential Successive Approximation Register (SAR) Analog-to-Digital Converter (ADC) with a programmable gain amplifier (PGA) used in the readout circuit of CMOS image sensor (CIS). SAR ADC adopts two-step scaled-reference voltages to realize 14-bit conversion, aimed at reducing the scale of capacitor array and avoiding using calibration to mitigate the impact of offset and mismatch. However, the reference voltage self-calibration algorithm is applied on the design to guarantee the precision of reference voltages, which affects the results of conversion. The three-way PGA provides three types of gains: 3x, 4x, and 6x, and samples at the same time to get three columns of pixel signal and increase the system speed. The pixel array of the mentioned CIS is 1026 × 1024 , and the pixel pitch is 12.5 μ m × 12.5 μ m . The prototype chip is fabricated in the 180 nm CMOS process, and both digital and analog voltages are 3.3 V. The total area of the chip is 6.25 × 18.38 mm2. At 150 kS/s sampling rate, the SNR of SAR ADC is 71.72 dB and the SFDR is 82.91 dB. What is more, the single SAR ADC consumes 477.2 uW with the 4.8 V PP differential input signal and the total power consumption of the CIS is about 613 mW.

The continuing improvement in quantum efficiency (above 90% for single visible photons), reduction in noise (below 1 electron per pixel), and shrink in pixel pitch (less than 1 micron) motivate billion-pixel X-ray cameras (BiPC-X) based on commercial CMOS imaging sensors. We describe BiPC-X designs and prototype construction based on flexible tiling of commercial CMOS imaging sensors with millions of pixels. Device models are given for direct detection of low energy X-rays ($, Comment: 6 pages, 8 figures

The GEMPix is a small gaseous detector with a highly pixelated readout, consisting of a drift region, three Gas Electron Multipliers (GEMs) for signal amplification, and four Timepix ASICs with 55 µm pixel pitch and a total of 262,144 pixels. A continuous flow of a gas mixture such as Ar:CO$_{2}$:CF$_{4}$, Ar:CO$_{2}$ or propane-based tissue equivalent gas is supplied externally at a rate of 5 L/h. This article reviews the medical applications of the GEMPix. These include relative dose measurements in conventional photon radiation therapy and in carbon ion beams, by which on-line 2D dose images provided a similar or better performance compared to gafchromic films. Depth scans in a water phantom with $^{12}$C ions allowed measuring the 3D energy deposition and reconstructing the Bragg curve of a pencil beam. Microdosimetric measurements performed in neutron and photon fields allowed comparing dose spectra with those from Tissue Equivalent Proportional Counters and, additionally, to obtain particle track images. Some preliminary measurements performed to check the capabilities as the detector in proton tomography are also illustrated. The most important on-going developments are: (1) a new, larger area readout to cover the typical maximum field size in radiation therapy of 20 × 20 cm$^{2}$; (2) a sealed and low-pressure version to facilitate measurements and to increase the equivalent spatial resolution for microdosimetry; (3) 3D particle track reconstruction when operating the GEMPix as a Time Projection Chamber. The GEMPix is a small gaseous detector with a highly pixelated readout, consisting of a drift region, three Gas Electron Multipliers (GEMs) for signal amplification, and four Timepix ASICs with 55 µm pixel pitch and a total of 262,144 pixels. A continuous flow of a gas mixture such as Ar:CO2:CF4, Ar:CO2 or propane-based tissue equivalent gas is supplied externally at a rate of 5 L/h. This article reviews the medical applications of the GEMPix. These include relative dose measurements in conventional photon radiation therapy and in carbon ion beams, by which on-line 2D dose images provided a similar or better performance compared to gafchromic films. Depth scans in a water phantom with 12C ions allowed measuring the 3D energy deposition and reconstructing the Bragg curve of a pencil beam. Microdosimetric measurements performed in neutron and photon fields allowed comparing dose spectra with those from Tissue Equivalent Proportional Counters and, additionally, to obtain particle track images. Some preliminary measurements performed to check the capabilities as the detector in proton tomography are also illustrated. The most important on-going developments are: (1) a new, larger area readout to cover the typical maximum field size in radiation therapy of 20 × 20 cm2; (2) a sealed and low-pressure version to facilitate measurements and to increase the equivalent spatial resolution for microdosimetry; (3) 3D particle track reconstruction when operating the GEMPix as a Time Projection Chamber.

Chromium compensated GaAs or GaAs:Cr sensors provided by the Tomsk State University (Russia) were characterized using the low noise, charge integrating readout chip JUNGFRAU with a pixel pitch of 75 × 75 µm2 regarding its application as an X-ray detector at synchrotrons sources or FELs. Sensor properties such as dark current, resistivity, noise performance, spectral resolution capability and charge transport properties were measured and compared with results from a previous batch of GaAs:Cr sensors which were produced from wafers obtained from a different supplier. The properties of the sample from the later batch of sensors from 2017 show a resistivity of 1.69 × 109 Ω/cm, which is 47% higher compared to the previous batch from 2016. Moreover, its noise performance is 14% lower with a value of (101.65 ± 0.04) e- ENC and the resolution of a monochromatic 60 keV photo peak is significantly improved by 38% to a FWHM of 4.3%. Likely, this is due to improvements in charge collection, lower noise, and more homogeneous effective pixel size. In a previous work, a hole lifetime of 1.4 ns for GaAs:Cr sensors was determined for the sensors of the 2016 sensor batch, explaining the so-called “crater effect” which describes the occurrence of negative signals in the pixels around a pixel with a photon hit due to the missing hole contribution to the overall signal causing an incomplete signal induction. In this publication, the “crater effect” is further elaborated by measuring GaAs:Cr sensors using the sensors from 2017. The hole lifetime of these sensors was 2.5 ns. A focused photon beam was used to illuminate well defined positions along the pixels in order to corroborate the findings from the previous work and to further characterize the consequences of the “crater effect” on the detector operation.

A high pixel density image sensor for the Short Wave Infrared (SWIR) range is presented. A PbS quantum dot (QD) photodiode array is monolithically integrated on a silicon custom readout IC. Imaging in VIS and SWIR is demonstrated using focal plane arrays with pixel pitch down to record 1.82 μm. Through-silicon vision and lens-free imaging (LFI) microscopy are shown as applications that can benefit from high resolution/small pixel dimensions. In the LFI demonstration, the captured hologram is computationally reconstructed to acquire SWIR microscopic images, resulting in a wavelength equivalent resolution LFI microscopy system. To our knowledge, this is the smallest pitch SWIR pixel ever reported and the first LFI system using a QD image sensor.

This paper presents a 64 mega-pixel, backside-illuminated, CMOS image sensor using a 0.7um pixel pitch with a 7.0ke- linear full well capacity (FWC). A switchable conversion gain design was also demonstrated to have a high 18.0ke- FWC in 4-Cell pixel binning mode. Several new processes were implemented to overcome pixel performance degradation due to pixel scaling. As a result, this high FWC image sensor achieves low dark noise of 1.26e- and high quantum efficiency, comparable to larger pixel pitch products, such as 0.8um.

International audience; The modulation transfer function (MTF) is one of the key figures of merit for the characterization of infrared focal plane arrays (FPA). Moreover, with both the trend of reduced pixel pitch and the variety of pixel structures observed in the industry, the study of the impact of wavelength on the MTF is also of great interest, and thus needs a spectro-spatial measurement. In this paper, we demonstrate such spectral MTF measurements in the mid-wavelength infrared (MWIR) band by the use of several spectral bandpass filters. We realize those measurements at 80 K on a specific n/p 320 × 256 HgCdTe MWIR FPA, divided into different areas. The pixel pitch is the same for all areas (30 μm), the only difference being the fill factor, which differs from one zone to another. The MTF measurement bench is based on a continuously self-imaging grating interferometer integrated in a specific cryogenic set-up.

Most modern energy resolving, photon counting detectors employ small (sub 1 mm) pixels for high spatial resolution and low per pixel count rate requirements. These small pixels can suffer from a range of charge sharing effects (CSEs) that degrade both spectral analysis and imaging metrics. A range of charge sharing correction algorithms (CSCAs) have been proposed and validated by different groups to reduce CSEs, however their performance is often compared solely to the same system when no such corrections are made. In this paper, a combination of Monte Carlo and finite element methods are used to compare six different CSCAs with the case where no CSCA is employed, with respect to four different metrics: absolute detection efficiency, photopeak detection efficiency, relative coincidence counts, and binned spectral efficiency. The performance of the various CSCAs is explored when running on systems with pixel pitches ranging from 100 &micro, m to 600&micro, m, in 50 &micro, m increments, and fluxes from 106 to 108 photons mm&minus, 2 s&minus, 1 are considered. Novel mechanistic explanations for the difference in performance of the various CSCAs are proposed and supported. This work represents a subset of a larger project in which pixel pitch, thickness, flux, and CSCA are all varied systematically.

A novel phase-detection auto focus (PDAF) technique for incident 850 nm plane wave is demonstrated using Ge-on-Si layer and deep trench isolation (DTI), which are locally arranged on light receiving surface (LRS) of crystalline silicon (c-Si). No metal light shielding film (LSF) for pupil division is formed. The key concept of the present work for PDAF is to perform the pupil division by the locally arranged Geon-Si layer in a pixel according to incident angle. The present pixel is based on a back-side illuminated CMOS image sensor pixel; the pixel pitch is 1.85 μm and the thickness of c-Si is around 3 μm. The simulation, based on three-dimensional finite difference time domain (3D-FDTD) method, shows that the external quantum efficiency (EQE) of the present pixel exhibits above 44.3 % with the maximum of 76.0 % for incident angles of - 30° to + 30°, owing to the selectively arranged Ge-on-Si layer; it exhibits 3.6 times improvement in the EQE at normal incidence compared to that of current state-of-the-art pixel with half metal-shielded aperture; the EQE is 49.2 % and 13.8 %, respectively. The present technique can enhance the accuracy of AF under low-illuminated condition.

The LHCb experiment is a detector at the LHC designed to capture decays of b- and c-hadrons for the study of CP violation and rare decays. At the end of Run-II, many of the LHCb measurements remain statistically dominated. For this reason the experiment is currently being transformed, in the Upgrade I programme, to run at higher luminosity from Run III onwards. The trigger scheme will be transformed to read out at 40 MHz to a flexible software trigger. In order to allow the new readout scheme the front end electronics will be changed, and the detectors need cope with the increased occupancy and radiation levels anticipated at the upgrade. The Vertex Locator (VELO) surrounding the interaction region, whose role is to reconstruct and trigger on the primary and secondary vertices of the events. The upgraded VELO is composed of 52 hybrid silcon pixel modules placed along the beam axis, divided into 2 retractable halves. Each module is equipped with 4 silicon pixel tiles, each read out by 3 VeloPix ASICs. The pixels have a square pitch of 55 microns and the sensors are produced in 0.2 mm thick p-in-n type silicon. The sensors must withstand an integrated fluence of $\mathrm{\mu m^2}$, a roughly equivalent dose of 400 MRad The highest occupancy ASICs will have pixel hit rates of 800 Mhit/sf, with a total rate of 1.6 Tbit/s for the whole detector. The VELO upgrade tiles are mounted onto a cooling substrate made of thin silicon plates with embedded micro-channels that allow the flow of liquid CO$_2$. The secondary vacuum in which the modules are located is separated from the beam vacuum by a thin custom made foil. This foil is be manufactured through a novel milling process and possibly thinned further by chemical etching. The upgraded VELO is currently under construction. The detector R\&D, module thermal performance, and the VELO Upgrade production status will be presented.

International audience; In augmented reality applications, high brightness at high resolution is crucial to guarantee a good user experience. Explorations on efficient light sources have already been undertaken, and GaN µLEDs tend to be a good candidate. Nevertheless, micro-display driving circuits usually do not provide sufficient luminance level to offer good contrast against ambient light. We report the design and fabrication of a GaN LED microdisplay driving circuit enabling, to our knowledge, the highest brightness for such a pixel pitch and resolution. The driving circuit was designed in a 0.18µm CMOS process with 1640x1033 resolution. Each LED is controlled individually by a CMOS pixel of 9.5µm pitch. A monochrome green microdisplay enables more than WSXGA resolution and can reach 3.8MCd/m² for a fully ON micro-LED array.

Real-time in-vitro multi-modality characterization of neuronal cell ensemble involves highly complex interdependent phenomena and processes. Although a variety of microelectrode arrays (MEAs) have been reported, diagnosis techniques are limited in term of sensing area, optical transparency, resolution and number of modalities. This paper presents an optically transparent thin-film-transistor (TFT) array biosensor chip for neuronal ensemble investigation, in which TFT electrodes are used for six modalities including extracellular voltage recording of both action potential (AP) and local field potential (LFP), current or voltage stimulation, chemical stimulation, electrical impedance measurement, and optical imaging. The sensor incorporates a large sensing area (15.6 mm × 15.6 mm) with a 200 × 150 array of indium-tin-oxide (ITO) electrodes placed at a 50 μm or 100 μm pixel pitch and with 10 ms temporal resolution; these performances are comparable to the state-of-the-art MEA devices. The TFT electrode array is designed based on the switch matrix architecture. The reliability and stability of TFTs are examined by measuring their electrical characteristics. Impedance spectroscopy function is verified by mapping the neuron position and the status (cells alive or dead, contamination) on the electrodes, which facilitates the biochemical studies in electrical domain that adds quantitative views to visual observation of cells through the optical microscopy. An in-vitro neuron culture is studied using electrophysiological, electrochemical, and optical characterization. Detailed signal analysis is demonstrated to prove the capability of bioassay.

We present a novel guard-ring-sharing technique to push the limit of SPAD pixel miniaturization, and to demonstrate the operation of SPAD arrays with a 2.2 mu m-pitch, the smallest ever reported. Device simulation and preliminary tests suggest that the optimized device design ensures the electrical isolation of SPADs with guard-ring sharing. 4x4 SPAD arrays with two parallel selective readout circuits are designed in 180 nm CMOS technology. SPAD characteristics for the pixel pitch of 2.2, 3, and 4 Inn are systematically measured as a function of an active diameter, active-to-active distance, and excess bias. For a 4 mu m-pitch, the fill factor is 42.4%, the maximum PDP 33.5%, the median DCR 2.5 cps, the timing jitter 88 ps, and the crosstalk probability is 3.57%, while the afterpulsing probability is 0.21%. Finally, we verified the feasibility of the proposed technique towards compact multi-megapixel 3D-stacked SPAD arrays. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

The first experimental results from a new type of transmissive synchrotron X-ray diagnostic instrument are presented. A chemical-vapour-deposition diamond plate with graphitic electrodes and a modulation lock-in signal acquisition technique are used to image the X-ray beam., The first experimental results from a new transmissive diagnostic instrument for synchrotron X-ray beamlines are presented. The instrument utilizes a single-crystal chemical-vapour-deposition diamond plate as the detector material, with graphitic wires embedded within the bulk diamond acting as electrodes. The resulting instrument is an all-carbon transmissive X-ray imaging detector. Within the instrument’s transmissive aperture there is no surface metallization that could absorb X-rays, and no surface structures that could be damaged by exposure to synchrotron X-ray beams. The graphitic electrodes are fabricated in situ within the bulk diamond using a laser-writing technique. Two separate arrays of parallel graphitic wires are fabricated, running parallel to the diamond surface and perpendicular to each other, at two different depths within the diamond. One array of wires has a modulated bias voltage applied; the perpendicular array is a series of readout electrodes. X-rays passing through the detector generate charge carriers within the bulk diamond through photoionization, and these charge carriers travel to the nearest readout electrode under the influence of the modulated electrical bias. Each of the crossing points between perpendicular wires acts as an individual pixel. The simultaneous read-out of all pixels is achieved using a lock-in technique. The parallel wires within each array are separated by 50 µm, determining the pixel pitch. Readout is obtained at 100 Hz, and the resolution of the X-ray beam position measurement is 600 nm for a 180 µm size beam.

Lithographic scaling of periodic three-dimensional patterns is critical for advancing scalable nanomanufacturing. Current state-of-the-art quadruple patterning or extreme-ultraviolet lithography produce a line pitch down to around 30 nm, which might be further scaled to sub-20 nm through complex post-fabrication processes. Herein, we report the use of three-dimensional (3D) DNA nanostructures to scale the line pitch down to 16.2 nm, around 50% smaller than state-of-the-art results. We use a DNA modular epitaxy approach to fabricate 3D DNA masks with prescribed structural parameters (geometry, pitch and critical dimensions) along a designer assembly pathway. Single-run reactive ion etching then transfers the DNA patterns to a Si substrate at a lateral critical dimension of 7 nm and a vertical critical dimension of 2 nm. The nanolithography guided by DNA modular epitaxy achieves a smaller pitch than the projected values for advanced technology nodes in field-effect transistors, and provides a potential complement to the existing lithographic tools for advanced 3D nanomanufacturing. Epitaxially grown 3D DNA masks with prescribed geometry, pitch and size improve the resolution of reactive ion etching-based nanolithography, scaling the line pitch down to 16.2 nm and the critical dimension size to 7.2 nm.

A novel pH value detection method was developed in this paper. A 10 μL droplet prepared by buffer solution (pH = 1.2 to pH = 10) was injected to the sensing area (i.e. designed interdigitated ITO electrode), and the resistance variation of the electrode was recorded to build up the model of pH concentration detection. The result indicated that the interdigitated electrode pattern with a line width of 500 µm and a line pitch of 100 µm was the most sensitive under various pH conditions. In addition, for the acid solution and alkali solution, when the interdigitated electrode pattern with a line width of 100 µm and a line pitch of 500 µm was more sensitive in the acid environment, whereas the interdigitated electrode pattern with a line width of 500 µm and a line pitch of 100 µm can be applied in the alkaline environment due to its great sensitivity. During the pH value monitoring, the response time of resistance changing was below 3 seconds to reach the steady-state resistance in all various pH conditions, and the correlation coefficient was over 0.9 validated by a quadratic regression in both acid and alkaline sensing verification.

Significant progress has been made to develop silicon pixel technologies for use in the vertex and tracker regions of the proposed Compact Linear Collider (CLIC) detector design. The electron-positron collisions generated by this linear accelerator provide a clean, low-radiation environment for the inner detectors. However, physics-driven performance targets, the CLIC beam structure, and occupancies from beam-induced backgrounds place challenging requirements on detector technologies for this region. A pixel pitch down to 25×25 μm$^2$ , material budget ≤ 0.2-2%X$_0$ per layer, average power dissipation of down to 50 mW cm$^{-2}$ , position resolution of 3-7 μm, and timing resolution as low as 5 ns are called for in the vertex and tracking detectors. To this aim, a comprehensive R&D programme is ongoing to design and test silicon pixel detectors to fulfil these specifications, including both monolithic and hybrid devices. These studies involve Allpix$^2$ Monte Carlo and TCAD simulations, advanced 65 nm ASIC and sensor design, laboratory testing, and beam tests of individual modules to determine the required performance parameters. The characterisation and simulation modelling of these devices has also lead to the development of a set of tools and software within the CLIC detector and physics (CLICdp) collaboration. This publication will present recent results from the technologies being developed and tested in view of the CLIC vertex and tracking detector requirements, such as various monolithic CMOS sensors, and fine pitch hybrid assemblies with planar sensors. Significant progress has been made to develop silicon pixel technologies for use in the vertex and tracker regions of the proposed Compact Linear Collider (CLIC) detector design. The electron-positron collisions generated by this linear accelerator provide a clean, low-radiation environment for the inner detectors. However, physics-driven performance targets, the CLIC beam structure, and occupancies from beam-induced backgrounds place challenging requirements on detector technologies for this region. A pixel pitch down to 25×25 μm2, material budget ≤ 0.2–2%X0 per layer, average power dissipation of down to 50 mW cm−2, position resolution of 3–7μm, and timing resolution as low as 5 ns are called for in the vertex and tracking detectors. To this aim, a comprehensive R&D programme is ongoing to design and test silicon pixel detectors to fulfil these specifications, including both monolithic and hybrid devices. These studies involve Allpix2 Monte Carlo and TCAD simulations, advanced 65 nm ASIC and sensor design, laboratory testing, and beam tests of individual modules to determine the required performance parameters. The characterisation and simulation modelling of these devices has also lead to the development of a set of tools and software within the CLIC detector and physics (CLICdp) collaboration. This publication will present recent results from the technologies being developed and tested in view of the CLIC vertex and tracking detector requirements, such as various monolithic CMOS sensors, and fine pitch hybrid assemblies with planar sensors. Significant progress has been made to develop silicon pixel technologies for use in the vertex and tracker regions of the proposed Compact Linear Collider (CLIC) detector design. The electron-positron collisions generated by this linear accelerator provide a clean, low-radiation environment for the inner detectors. However, physics-driven performance targets, the CLIC beam structure, and occupancies from beam-induced backgrounds place challenging requirements on detector technologies for this region. A pixel pitch down to 25 x 25$\mu$m$^{-2}$, material budget $\leq$ 0.2-2$\%X_0$ per layer, average power dissipation of down to 50mWcm$^{-2}$, position resolution of 3-7$\mu$m, and timing resolution as low as 5ns are called for in the vertex and tracking detectors. To this aim, a comprehensive R&D programme is ongoing to design and test silicon pixel detectors to fulfil these specifications, including both monolithic and hybrid devices. These studies involve Allpix$^2$ Monte Carlo and TCAD simulations, advanced 65nm ASIC and sensor design, laboratory testing, and beam tests of individual modules to determine the required performance parameters. The characterisation and simulation modelling of these devices has also lead to the development of a set of tools and software within the CLIC detector and physics (CLICdp) collaboration. This publication will present recent results from the technologies being developed and tested in view of the CLIC vertex and tracking detector requirements, such as various monolithic CMOS sensors, and fine pitch hybrid assemblies with planar sensors.

LAPAN-A4 satellite is the next microsatellite under development in satellite technology centre LAPAN. One of payload on LAPAN-A4 satellite is SWIR camera. SWIR camera is provide by Xenics, with specifications array type using InGaAs, spectral band 1.45 – 1.66 µm, pixels 2,048, pixel pitch 12.5 µm, frame rate 10 kHz, 14 bit processing data, interface using based camera link (CL), power input 12 V, and operating temperature -40°C to 80°C. The aim of this research is to determine of radiometric characterization the SWIR camera image in conditions without illumination and illumination, and hope to be reference of pre-flight data. Methodology in this research, consists of measurement, image processing, analysis, and conclusion. In measurement step, there are two step of measurement are dark measurement, and flat field measurement using integrating sphere as uniform light source. The result of this research shows that the characteristic of the SWIR camera are dark image influenced by temperature, exposure time has a nonlinear pattern, the gain used is the device gain has an optimal value at 13, the camera offset has a fluctuating pattern that is low value in multiples of 20,000 and the highest value in multiples of 15,000 but the best setting in SWIR camera is at zero.

Large-format single-photon avalanche diode (SPAD) arrays often suffer from low fill-factors—the ratio of the active area to the overall pixel area. The detection efficiency of these detector arrays can be vastly increased with the integration of microlens arrays designed to concentrate incident light onto the active areas and may be refractive or diffractive in nature. The ability of diffractive optical elements (DOEs) to efficiently cover a square or rectangular pixel, combined with their capability of working as fast lenses (i.e., ∼ f / 3 ) makes them versatile and practical lens designs for use in sparse photon applications using microscale, large-format detector arrays. Binary-mask-based photolithography was employed to fabricate fast diffractive microlenses for two designs of 32 × 32 SPAD detector arrays, each design having a different pixel pitch and fill-factor. A spectral characterization of the lenses is performed, as well as analysis of performance under different illumination conditions from wide- to narrow-angle illumination (i.e., f / 2 to f / 22 optics). The performance of the microlenses presented exceeds previous designs in terms of both concentration factor (i.e., increase in light collection capability) and lens speed. Concentration factors greater than 33 × are achieved for focal lengths in the substrate material as short as 190 µ m , representing a microlens f-number of 3.8 and providing a focal spot diameter of < 4 µ m . These results were achieved while retaining an extremely high degree of performance uniformity across the 1024 devices in each case, which demonstrates the significant benefits to be gained by the implementation of DOEs as part of an integrated detector system using SPAD arrays with very small active areas.

We generate arbitrary 1-dimensional spatial profiles in a laser pulse by mapping the temporal electrical waveform sent to an acousto-optic modulator (AOM). The AOM can be therefore used as a spatial light modulator with 50 q,m pixel pitch, fast refresh rate, and high damage threshold.

We propose to use high numerical aperture single mode optical fibers like photonic crystal fiber for lensless in-line holographic microscopy. Highly divergent beam helps to overcome the spatial sampling limitation of the image sensor. In this paper, a submicron lateral resolution has been demonstrated, with an imaging sensor of pixel pitch 1.12 μm and a photonic crystal fiber of mode field diameter 1.8 μm. In earlier methods of single-shot lensless imaging, submicron resolution has been obtained at very small working distance and field of view. The proposed method improves the resolution without compromising the working distance. A working distance (but not limited to) ~ 1.7 mm with a field of view ~ 1.4 mm has been demonstrated.

An extensive R\&D program aiming at radiation hard, small pitch, 3D pixel sensors has been put in place % in CMS between Istituto Nazionale di Fisica Nucleare (INFN, Italy) and FBK Foundry (Trento, Italy). The CMS experiment is supporting % profiting of these developments the R\&D in the scope of the Inner Tracker upgrade for the High Luminosity phase of the CERN Large Hadron Collider (HL-LHC). In the HL-LHC the Inner Tracker will have to withstand an integrated fluence up to $2.3 \times 10^{16} \, \mathrm{n_{eq}/cm^2}$. % (1 MeV equivalent neutrons). A small number of 3D sensors were interconnected with the RD53A readout chip, which is the first prototype of 65 nm CMOS pixel readout chip designed for the HL-LHC pixel trackers. In this paper results obtained in beam tests before and after irradiation are reported. Irradiation of a single chip %interconnected module was performed up to a maximum equivalent fluence of about $1 \times 10^{16} \, \mathrm{n_{eq}/cm^2}$. Analysis of the collected data shows excellent performance: spatial resolution in not irradiated (fresh) sensors is about 3 to 5 $\mathrm{ \mu }$m depending on the pixel pitch. Hit detection efficiencies are close to 99\% measured both before and after the above mentioned irradiation fluence.