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We discuss the joint development by Penn State University (PSU) and Teledyne Imaging Systems (TIS) of hybrid CMOS detectors for X-ray astronomy, and specifically the development over the past 10 years of a new event-driven X-ray detector for future astronomy missions. This novel X-ray detector is designed to perform onchip event recognition and to read out only pixels containing X-ray events. With the exception of analog power supply voltages, the detector is digital in/digital out, reducing off-chip electronics to a minimum. It operates at frame rates of over 1000 frames per second, providing excellent performance for bright X-ray sources and/or high-throughput optics. The pixel size is 40 × 40 microns, and we are fabricating devices with 550 × 550 pixels.

The detector system for the Euclid Near-Infrared Spectrometer and Photometer (NISP) instrument is a 4×4 mosaic focal plane of 16 H2RG (2K×2K pixels) infrared Sensor Chip Assemblies (SCAs) and 16 SIDECAR ASIC Sensor Chip Electronics (SCE) modules. Teledyne has successfully completed the fabrication, testing, and delivery of 24 sciencegrade flight candidate SCAs to the NASA Jet Propulsion Laboratory (JPL). These SCAs were made with Teledyne’s TRL-9 substrate-removed MBE mercury cadmium telluride (HgCdTe) 2.3 μm cutoff detector material and low-noise H2RG CMOS readout chip. The SCAs are mounted on a buttable molybdenum package that enables close packing of the 16 flight SCAs in the NISP focal plane. In this paper, we present the test results of the 24 Euclid flight candidate SCAs. The key detector performance parameters that are critical to the NISP instrument are: high in-band quantum efficiency with good spatial uniformity, low readout noise, low dark current with tight distribution, low pixel crosstalk, low persistence, and good detector surface metrology profile. All 24 SCAs exceed the Euclid NISP performance and interface requirements. The additional acceptance testing at JPL and NASA Goddard’s Detector Characterization Lab has also been completed. 20 flight SCAs have been delivered to European Space Agency (ESA).

We report our progress toward optimizing backside-illuminated silicon PIN CMOS devices developed by Teledyne Imaging Sensors (TIS) for far-UV planetary science applications. This project was motivated by initial measurements at Southwest Research Institute (SwRI) of the far-UV responsivity of backside-illuminated silicon PIN photodiode test structures described in Bai et al., SPIE, 2008, which revealed a promising QE in the 100-200 nm range as reported in Davis et al., SPIE, 2012. Our effort to advance the capabilities of thinned silicon wafers capitalizes on recent innovations in molecular beam epitaxy (MBE) doping processes. Key achievements to date include: 1) Representative silicon test wafers were fabricated by TIS, and set up for MBE processing at MIT Lincoln Laboratory (LL); 2) Preliminary far-UV detector QE simulation runs were completed to aid MBE layer design; 3) Detector fabrication was completed through the pre-MBE step; and 4) Initial testing of the MBE doping process was performed on monitoring wafers, with detailed quality assessments. Early results suggest that potential challenges in optimizing the UV-sensitivity of silicon PIN type CMOS devices, compared with similar UV enhancement methods established for CCDs, have been mitigated through our newly developed methods. We will discuss the potential advantages of our approach and briefly describe future development steps.

Teledyne’s silicon hybrid CMOS focal plane array technology has matured into a viable, high performance and high- TRL alternative to scientific CCD sensors for space-based applications in the UV-visible-NIR wavelengths. This paper presents the latest results from Teledyne’s low noise silicon hybrid CMOS visible focal place array produced in 4K×4K format with 10 μm pixel pitch. The H4RG-10 readout circuit retains all of the CMOS functionality (windowing, guide mode, reference pixels) and heritage of its highly successful predecessor (H2RG) developed for JWST, with additional features for improved performance. Combined with a silicon PIN detector layer, this technology is termed HyViSI™ (Hybrid Visible Silicon Imager). H4RG-10 HyViSI™ arrays achieve high pixel interconnectivity (

We describe vacuum ultraviolet sensitivity measurements of a new high performance silicon-based CMOS sensor from Teledyne Imaging Sensors. These sensors do not require the high voltages of MCP detectors, making them a lower mass and power alternative to the more mature MCP technology. These devices demonstrate up to 40 percent quantum efficiency at vacuum ultraviolet wavelengths, either meeting or greatly exceeding 10 percent quantum efficiency across the entire 100-200 nm wavelength region. As with similar visible sensitive devices, backside illumination results in a higher quantum efficiency than frontside illumination. Measurements of the vacuum ultraviolet sensitivity of the Teledyne silicon PIN detectors were made by directing a known intensity of ultraviolet light at discrete wavelengths onto the test detectors and reading out the resulting photocurrent. The sensitivity of the detector at a given wavelength was then calculated from the intensity and wavelength of the incoming light and the relative photodiode to NIST-traceable calibration diode active areas. A custom electromechanical interface was developed to make these measurements within the SwRI Vacuum Radiometric Calibration Chamber. While still in the single pixel stage, full 1K × 1K focal plane arrays are possible using existing CMOS readout electronics and hold great promise for inclusion in future spaceflight instrument concepts.

The development of Hybrid CMOS Detectors (HCDs) for X-Ray telescope focal planes will place them in con- tention with CCDs on future satellite missions due to their faster frame rates, flexible readout scenarios, lower power consumption, and inherent radiation hardness. CCDs have been used with great success on the current generation of X-Ray telescopes (e.g. Chandra, XMM, Suzaku, and Swift). However their bucket-brigade read-out architecture, which transfers charge across the chip with discrete component readout electronics, results in clockrate limited readout speeds that cause pileup (saturation) of bright sources and an inherent susceptibility to radiation induced displacement damage that limits mission lifetime. In contrast, HCDs read pixels with low power, on-chip multiplexer electronics in a random access fashion. Faster frame rates achieved with multi-output readout design will allow the next generation's larger effective area telescopes to observe bright sources free of pileup. Radiation damaged lattice sites effect a single pixel instead of an entire row. Random access, multi-output readout will allow for novel readout modes such as simultaneous bright-source-fast/whole-chip-slow readout. In order for HCDs to be useful as X-Ray detectors, they must show noise and energy resolution performance similar to CCDs while retaining advantages inherent to HCDs. We will report on readnoise, conversion gain, and energy resolution measurements of an X-Ray enhanced Teledyne HAWAII-1RG (H1RG) HCD and describe techniques of H1RG data reduction., 11 pages, 10 figures

In a joint program of Penn State University and Teledyne Imaging Sensors, hybrid CMOS sensors have been developed for use as X-ray detectors. This detector technology can provide major improvements in performance relative to CCDs, which are the current standard technology used in the focal planes of X-ray telescopes (e.g. Chandra, XMM, Suzaku, and Swift). Future X-ray telescope missions are all likely to have significantly increased collection area. If standard CCDs are used, the effects of saturation (pile-up) will have a major impact, while radiation damage will impact the quality and lifetime of the detectors. By reading out the hybrid CMOS detector in a pixel-by-pixel fashion at high speeds, with an energy resolution similar to CCDs, CMOS sensors could increase the range of pile-up free operation by several orders of magnitude. They are also several orders of magnitude more radiation hard than typical CCDs since they transfer charge through the thickness of the device, rather than across the length of its surface. Furthermore, hybrid CMOS detectors can be programmed to read out any variety of windowed regions, which leads to versatility and speed. All of this can be achieved, in principle, while maintaining the same quantum efficiencies achievable in CCDs. Results of this development effort and preliminary tests of fabricated detectors will be presented, along with potential applications for future missions such as EDGE and Constellation-X.

We have fabricated a new experimental pixel array using 2mm-thick CdZnTe. The trial arrays have been bump-bonded to the Rockwell PICNIC readout IC which provides low noise read out of pixel signals. First measurements are presented from the detector characterisation, which in particular, demonstrate that a very high bond yield (>99%) was achieved. It is envisaged that these detectors will be suitable for future X-ray astronomy and planetary missions as well as ground based applications such as non-destructive testing, threat detection and baggage scanning.

Rockwell Space Center is developing low-noise visible and IR imaging sensors and systems for astronomy, high-end commercial, NASA, and advanced military applications. The first science grade 2048 by 2048 HAWAII-2 focal plane array (FPA) for astronomy was recently demonstrated for the SWIR waveband. Science-grade deliveries to the University of Hawaii's Institute for Astronomy, the European Southern Observatory and the Subaru Telescope, among others, will soon start. MWIR/visible 2048 by 2048 HAWAII-2 arrays are also being developed for the NGST program using our process for removing the CdZnTe substrate from the back-side illuminated HgCdTe FPAs to detect visible radiation in addition to IR. Previously, more than 25 science grade 2.5micrometers 1024 by 1024 HAWAII FPAs were delivered for use in many observatories; these typically exhibit 90 percent with near-100 percent fill factor, and the dark current is negligible with minimum cooling. Our near-term plan to develop 4096 by 4096 visible and IR FPAs will also be discussed.

Silicon-based hybrid CMOS visible focal plane array (FPA) technology is emerging as a strong contender for scientific applications that require broad spectral response with low noise, highly integrated functionality and radiation hardness. CMOS-based FPAs offer many advantages in high speed, low-noise detection and signal processing. As a high performance alternative to advanced CCD imaging arrays, the hybrid design enables independent optimization of the silicon detector array and silicon readout electronics. Multiplexer commonality with the instrument's IR channels is another attractive feature for integrators of sensor sites such as for hyperspectral spectrometers. In this paper, the technical merits of Rockwell's CMOS-based hybrid visible FPAs are described including key detector performance aspects, interface electronics requirements, radiation hardness and concomitant implications for diverse imaging applications. At this time we have developed 640 X 480 and 1024 X 1024 hybrid imagers with approximately equals 100% optical fill factor, high broadband QE spanning ultraviolet (UV) through near infrared (NIR), wide dynamic range, and high pixel operability. Dark current of approximately equals 0.01e-/sec and read noise approximately equals 6e- have been measured on one prototype 1024 X 1024 FPA that uses Hawaii readout integrated circuit (ROIC). Initial radiation data indicate a total ionization dose (TID) tolerance greater than 35 Krad for our standard CMOS process.