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A sensor device comprising a planar substrate defining a substrate plane and a waveguide for guiding an electromagnetic wave. The waveguide extends in a length direction in a waveguide plane parallel to the substrate plane and has a width and a height wherein the width to height ratio is more than 5. The height of the waveguide is less than the wavelength of the electromagnetic wave. The waveguide is supported on the substrate by a support structure extending from the substrate to the waveguide, along the length direction of the waveguide, having a width which is smaller than the width of the waveguide. The invention further relates to a method of detecting a component in gas and a method of fabricating a sensor device., QC 20210226

Carbon dioxide (CO2) is a gas vital for life on Earth. It is also a waste product of human activities and is widely used in agriculture and industry. Its accurate sensing is therefore of great interest. Optical sensors exploiting the mid-infrared light absorption of CO2 provide high selectivity, but their large size and high cost limit their use. In this Letter, we demonstrate CO2 gas sensing at 4.2 µm wavelength using an integrated silicon waveguide, featuring a sensitivity to CO2 of 44% that of free-space sensing. The suspended waveguide is fabricated on a silicon-on-insulator substrate by a single-lithography-step process, and we route it into a mid-infrared photonic circuit for on-chip-referenced gas measurements. Its demonstrated performance and its simple and scalable fabrication make our waveguide ideal for integration in miniaturized CO2 sensors for distributed environmental monitoring, personal safety, and medical and high-volume consumer applications.

We review our recent work on spectroscopic sensing of carbon dioxide in the mid-infrarded region around 4.3 µm using suspended silicon waveguides. Our waveguides are built on standard silicon-on-insulator substrates and acheive high sensitivity to gas., Part of proceedings: ISBN 9781557528209, QC 20220613

We present a low-confinement Si waveguide for 4.26 μm wavelength and apply it to sense CO2 concentrations down to 0.1 %. We demonstrate the highest reported waveguide sensitivity to CO2: 44 % of the free-space sensitivity., SyskonpostNot duplicate with DIVA 1327380QC 20211012

We present a low-confinement Si waveguide for 4.26 μm wavelength and applyit to sense CO2 concentrations down to 0.1 %. We demonstrate the highest reportedwaveguide sensitivity to CO2: 44% of the free-space sensitivity., QC 20190802

We demonstrate the first uncooled single-nanowire-based infrared bolometer to detect sub-mW optical signals up to MHz frequencies. The bolometer consists of a Pt nanowire on a suspended silicon hybrid-plasmonic cavity, and exhibits enhanced optical responsivity compared to nanowires on unstructured and non-suspended substrates. Low-cost monolithically integrated infrared detectors are needed for the rapidly growing field of silicon photonic sensors. The high speed of our nanobolometer enables advanced modulation schemes for noise reduction and avoidance of low-frequency thermal cross-talk, as well as power saving by pulsed operation. Furthermore, its simple integration and small footprint make it a cost effective detector for sensing applications., QC 20170124

Metal nanowires can emit coherent polarized thermal radiation, work as uncooled bolometers, and provide localized heating. In this paper, we engineer the temperature dynamics of electrically driven Pt nanoheaters on a silicon-on-insulator substrate. We present three designs and we electrically characterize and model their thermal impedance in the frequency range from 3 Hz to 3 MHz. Finally, we show a temperature modulation of 300 K while consuming less than 5 mW of power, up to a frequency of 1.3 MHz. This result can lead to significant advancements in thermography and absorption spectroscopy., QC 20160523

[EN] We report on dye-based photonic sensing systems which are fabricated and packaged at wafer scale. For the first time luminescent organic nanocomposite thin-films deposited by plasma technology are integrated in photonic sensing systems as active sensing elements. The realized dye-based photonic sensors include an environmental NO2 sensor and a sunlight ultraviolet light (UV) A + B sensor. The luminescent signal from the nanocomposite thin-films responds to changes in the environment and is selectively filtered by a photonic structure consisting of a Fabry Perot cavity. The sensors are fabricated and packaged at wafer-scale, which makes the technology viable for volume manufacturing. Prototype photonic sensor systems have been tested in real-world scenarios.

We report on dye-based photonic sensing systems which are fabricated and packaged at wafer scale. For the first time luminescent organic nanocomposite thin-films deposited by plasma technology are integrated in photonic sensing systems as active sensing elements. The realized dye-based photonic sensors include an environmental NO₂ sensor and a sunlight ultraviolet light (UV) A + B sensor. The luminescent signal from the nanocomposite thin-films responds to changes in the environment and is selectively filtered by a photonic structure consisting of a Fabry–Perot cavity. The sensors are fabricated and packaged at wafer-scale, which makes the technology viable for volume manufacturing. Prototype photonic sensor systems have been tested in real-world scenarios.

We report on dye-based photonic sensing systems which are fabricated and packaged at wafer scale. For the first time luminescent organic nanocomposite thin-films deposited by plasma technology are integrated in photonic sensing systems as active sensing elements. The realized dye-based photonic sensors include an environmental NO sensor and a sunlight ultraviolet light (UV) A + B sensor. The luminescent signal from the nanocomposite thin-films responds to changes in the environment and is selectively filtered by a photonic structure consisting of a Fabry-Perot cavity. The sensors are fabricated and packaged at wafer-scale, which makes the technology viable for volume manufacturing. Prototype photonic sensor systems have been tested in real-world scenarios.

A sensor device comprising a planar substrate defining a substrate plane and a waveguide for guiding an electromagnetic wave. The waveguide extends in a length direction in a waveguide plane parallel to the substrate plane and has a width and a height, wherein the width to height ratio is more than 5. The height of the waveguide is less than the wavelength of the electromagnetic wave. The waveguide is supported on the substrate by a support structure extending from the substrate to the waveguide, along the length direction of the waveguide, having a width which is smaller than the width of the waveguide. The invention further relates to a method of detecting a component in gas and a method of fabricating a sensor device., QC 20191211

We present a method to characterize the temperature dynamics of miniaturized thermal IR sources. The method circumvents the limitations of current IR photodetectors, by relying only on an electrical measurement rather than on optical detection. Thus, it enables the characterization of the light emission of IR sources over their full operation frequency range. Moreover, we develop a model of thermal IR sources allowing simulations of their thermal and electrical behavior. By combining measurements and modeling, we achieve a comprehensive characterization of a Pt nanowire IR source: the reference resistance R-0 = 17.7 Omega, the TCR alpha = 2.0 x 10(-3) K-1, the thermal mass C = 2.7 x 10(-14) J/K, and the thermal conductance G = 1.3 x 10(-6) W/K. The thermal time constant could not be measured, because of the frequency limitation of our setup. However, the operation of the source has been tested and proved to function up to 1 MHz, indicating that the thermal time constant of the source is smaller than 1 mu s., QC 20140813, GASENS

This paper reports on a novel wafer-level packaging method employing gold gaskets and an epoxy underfill. The packaging is done at room-temperature and atmospheric pressure. The mild packaging conditions allow the encapsulation of sensitive devices. The method is demonstrated for two applications; the wafer-level encapsulation of a liquid and the wafer-level packaging of a photonic gas sensor containing heat sensitive dye-films., QC 20131129, Phodye

We present a single-lithography Mach-Zehnder interferometer sensor circuit, with integrated low back-reflection input and output grating couplers. The low back-reflection is accomplished by a duty cycle apodization optimized for coupling light between single-mode silica fibers and the nanometric silicon-on-insulator (SOI) rib-waveguides. We discuss the design, fabrication, and characterization of the circuit. The apodization profile of the gratings is algorithmically generated using eigenmode expansion based simulations and the integrated waveguides, splitters, and combiners are designed using finite element simulations. The maximum simulated coupling efficiencies of the gratings are 70% and the multimode interference splitters and combiners have a footprint of only 19.2ￜ4.5 ￜm2. The devices are fabricated on an SOI wafer with a 220 nmdevice layer and 2 ￜm buried oxide, by a single electron beam lithography and plasma etching. We characterize the devices in the wavelength range from 1460-1580 nm and show a grating pass-band ripple of only 0.06 dB and grating coupling efficiency of 40% at 1530 nm. The integrated Mach-Zehnder interferometer has an extinction ratio of -18 dB at 1530 nm and between -13 and -19 dB over the whole 1460-1580 nm range., QC 20120612, Cell-Ring

Label-free photonic biosensors fabricated on silicon-on-insulator (SOI) can provide compact size, high evanescent field strength at the silicon waveguide surface, and volume fabrication potential. However, due to the large thermo optic coefficient of water-based biosamples, the sensors are temperature-sensitive. Consequently, active temperature control is usually used. However, for low cost applications, active temperature control is often not feasible. Here, we use the opposite polarity of the thermo-optic coefficients of silicon and water to demonstrate a photonic slot waveguide with a distribution of power between sample and silicon that aims to give athermal operation in water. Based on simulations, we made three waveguide designs close to the athermal point, and asymmetric integrated Mach- Zehnder interferometers for their characterization. The devices were fabricated on SOI with a 220 nm device layer and 2 ï¿œm buried oxide, by electron beam lithography of hydrogen silsesquioxane (HSQ) resist, and etching in a Cl2/HBr/O2/He plasma. With Cargile 50350 fused silica matching oil as top cladding, the group index of the three guides varies from 1.9 to 2.8 at 1550 nm. The temperature sensitivity of the devices varied from -70 to -160 pm/K under the same conditions. A temperature sensitivity of -2 pm/K is projected with water as top cladding., QC 20120613

QC 20130521

In this paper, we describe the ideas behind a second-year Design-Build course in Electrical Engineering. Electrical Engineering is a theoretical subject, and in such it is difficult to maintain the theoretical level in project courses introduced too early in the program, especially when core subjects like electromagnetic field theory are involved. This issue is addressed and we also describe our approach for the assessment of the students. We also discuss the different goals that were set up prior to the course from a program perspective; how we reasoned when designing the course, the assessment structure, and the output once the course was implemented, QC 20150417

We present the design, fabrication, and characterization of a grating for coupling between a single mode silica fiber and the TE mode in a silicon photonic waveguide on a silicon on insulator (SOI) substrate. The grating is etched completely through the silicon device layer, thus permitting the fabrication of through-etched surface coupled silicon nanophotonic circuits in a single lithography step. Furthermore, the grating is apodized to match the diffracted wave to the mode profile of the fiber. We experimentally demonstrate a coupling efficiency of 35% with a 1 dB bandwidth of 47 nm at 1536 nm on a standard SOI substrate. Furthermore, we show by simulation that with an optimized buried oxide thickness, a coupling efficiency of 72% and a 1 dB bandwidth of 38 nm at 1550 nm is achievable. This is, to our knowledge, the highest simulated coupling efficiency for single-etch TE-mode grating couplers. In particular, simulations show that apodizing a conventional periodic through-etched grating decreases the back-reflection into the waveguide from 21% to 0.1%., QC 20110419

A new kind of visible-blind organic thin-film material, consisting of a polymeric matrix with a high concentration of embedded 3-hydroxyflavone (3HF) dye molecules, that absorbs UV light and emits green light is presented. The thin films can be grown on sensitive substrates, including flexible polymers and paper. Their suitability as photonic active components in photonic devices is demonstrated., QC 20110307

We present the design, fabrication, and experimental characterization of a silicon surface grating coupler that enables the creation of complete photonic nanowire sensor circuits in a single lithography step on a standard SOI wafer. This advance is achieved without sacrifices in the coupling efficiency through the use of an apodization algorithm that tunes the width of each gap and bar in the grating. This design optimization provides a high light coupling efficiency and a low back reflection with a grating etched fully through the SOI device layer. We experimentally demonstrate a coupling efficiency of 35% on a standard SOI substrate at a wavelength of 1536 nm, and show that with an optimized buried oxide (BOX) thickness, a coupling efficiency of 72% could be achieved., Poster presentation.© 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20111110

The inside cover shows two types of photonic structures selectively deposited with a highly fluorescent and transparent organic thin film, as reported by Angel Barranco and co-workers on p. 761. These structures select and couple the green luminescence of the organic film up to the waveguide outputs in the photonic chip edge. The luminescent films are grown by a gentle deposition process fully compatible with sensitive and flexible substrates and easily scalable at the wafer level.

[EN] A new kind of visible-blind organic thin-film material, consisting of a polymeric matrix with a high concentration of embedded 3-hydroxyflavone (3HF) dye molecules, that absorbs UV light and emits green light is presented. The thin films can be grown on sensitive substrates, including flexible polymers and paper. Their suitability as photonic active components photonic devices is demonstrated.

We present the design, fabrication, and characterisation of an array of optical slot-waveguide ring resonator sensors, integrated with microfluidic sample handling in a compact cartridge, for multiplexed real-time label-free biosensing. Multiplexing not only enables high throughput, but also provides reference channels for drift compensation and control experiments. Our use of alignment tolerant surface gratings to couple light into the optical chip enables quick replacement of cartridges in the read-out instrument. Furthermore, our novel use of a dual surface-energy adhesive film to bond a hard plastic shell directly to the PDMS microfluidic network allows for fast and leak-tight assembly of compact cartridges with tightly spaced fluidic interconnects. The high sensitivity of the slot-waveguide resonators, combined with on-chip referencing and physical modelling, yields a volume refractive index detection limit of 5 x 10(-6) refractive index units (RIUs) and a surface mass density detection limit of 0.9 pg mm(-2), to our knowledge the best reported values for integrated planar ring resonators., QC 20100715

We present an experimental study of an integrated slot-waveguide refractive index sensor array fabricated in silicon nitride on silica. We study the temperature dependence of the slot-waveguide ring resonator sensors and find that they show a low temperature dependence of -16.6 pm/K, while at the same time a large refractive index sensitivity of 240 nm per refractive index unit. Furthermore, by using on-chip temperature referencing, a differential temperature sensitivity of only 0.3 pm/K is obtained, without individual sensor calibration. This low value indicates good sensor-to-sensor repeatability, thus enabling use in highly parallel chemical assays. We demonstrate refractive index measurements during temperature drift and show a detection limit of 8.8 x 10(-6) refractive index units in a 7 K temperature operating window, without external temperature control. Finally, we suggest the possibility of athermal slot-waveguide sensor design., QC 20100715, SABIO

Point-of-care diagnostic devices typically require six distinct qualities: they must deliver at least the same sensitivity and selectivity, and for a cost per assay no greater than that of today's central lab technologies, deliver results in a short period of time (<15 min at GP; <2h in hospital), be portable or at least small in scale, and require no or extremely little sample preparation. State-of-the-art devices deliver information of several markers in the same measurement., QC 20110509

Dye molecules embedded in different matrices in the form of thin films are the basis of specific materials used for laser cavities, optical filters, optical gas sensors, etc. In the present communication we discuss a new methodology based on the remote microwave plasma assisted deposition of dye containing thin films that circumvent the above mentioned problems. It permits a tailored synthesis of optically active nanometric thin films containing dye molecules which are active as fluorescence emitters (i.e., coloured and fluorescent films). The principle of this new procedure is the partial polymerization of dye molecules that are evaporated over a substrate while exposed to a remote microwave Ar plasma. As a result of this process a polymeric thin film is produced in one step where some dye molecules keep intact their optical activity (although eventually, their optical response can be slightly modified by matrix effects). This methodology has been recently used for the deposition of novel plasma nanocomposites containing non-aggregated laser dyes to maximize the fluorescent emission of the materials and for the fabrication of optical NO2 sensing nanocomposites. To illustrate the possibilities of the technique we present here results for different fluorescent dye molecules, as perylene dyes, and several xanthene and oxazine derivative cationic dyes which are typically used as gain media in tuneable laser dyes. The luminescent, optical and sensing properties of these dye containing nanocomposites will be presented. These active optical layers are being developed for the fabrication of photonic sensor devices, optical filters and photonic chips (PHODYE EU Project). This is due to the full compatibility of the synthetic methodology with the present integrated microelectronic and optoelectronic technology. The possibilities for the fabrication of photonic devices integrating these active optical layers will be demonstrated. Especial attention will be paid to recent resu, QC 20111130, PHODYE

We review the use of planar integrated optical waveguide ring resonators for label free bio-sensing and present recent results from two European biosensor collaborations: SABIO and InTopSens. Planar waveguide ring resonators are attractive for label-free biosensing due to their small footprint, high Q-factors, and compatibility with on-chip optics and microfluidics. This enables integrated sensor arrays for compact labs-on-chip. One application of label-free sensor arrays is for point-of-care medical diagnostics. Bringing such powerful tools to the single medical practitioner is an important step towards personalized medicine, but requires addressing a number of issues: improving limit of detection, managing the influence of temperature, parallelization of the measurement for higher throughput and on-chip referencing, efficient light-coupling strategies to simplify alignment, and packaging of the optical chip and integration with microfluidics. From the SABIO project we report refractive index measurement and label-free biosensing in an 8-channel slot-waveguide ring resonator sensor array, within a compact cartridge with integrated microfluidics. The sensors show a volume sensing detection limit of 5x10(-6) RIU and a surface sensing detection limit of 0.9 pg/mm(2). From the InTopSens project we report early results on silicon-on-insulator racetrack resonators., QC 20101022

QC 20111123, Rappid

QC 20111123. Poster presentation.

QC 20111123

Accurate extraction of optical signals and multiple sensors on a single optical chip enable low-cost detection of specific proteins at the doctor's desk., QC 20111123

QC 20111129, Rappid

We present here research work on two optical biosensors which have been developed within two separate European projects (6(th) and 7(th) EU Framework Programmes). The biosensors are based on the idea of a disposable biochip, integrating photonics and microfluidics, optically interrogated by a multichannel interrogation platform. The objective is to develop versatile tools, suitable for performing screening tests at Point of Care or for example, at schools or in the field. The two projects explore different options in terms of optical design and different materials. While SABIO used Si(3)N(4)/SiO(2) ring resonators structures, P3SENS aims at the use of photonic crystal devices based on polymers, potentially a much more economical option. We discuss both approaches to show how they enable high sensitivity and multiple channel detection. The medium term objective is to develop a new detection system that has low cost and is portable but at the same time offering high sensitivity, selectivity and multiparametric detection from a sample containing various components (e. g. blood, serum, saliva, etc.). Most biological sensing devices already present on the market suffer from limitations in multichannel operation capability (either the detection of multiple analytes indicating a given pathology or the simultaneous detection of multiple pathologies). In other words, the number of different analytes that can be detected on a single chip is very limited. This limitation is a main issue addressed by the two projects. The excessive cost per test of conventional bio sensing devices is a second issue that is addressed., QC 20111109

We present an efficient and highly alignment-tolerant light coupling and distribution system for a multichannel Si3N4/SiO2 single-mode photonics sensing chip. The design of the input and output couplers and the distribution splitters is discussed. Examples of multichannel data obtained with the system are given., QC 20100525

QC 20111115. Oral presentation.

We present the design, fabrication, and characterization of a packaged array of individually addressable slot-waveguide ring resonator sensors in a compact cartridge for sensitive, label-free, multiplex assays. The novel use of a dual surfaceenergy adhesive film enables simple generic packaging method for multiple sensors in a single cartridge. The use of optical slot-waveguides, and drift compensation by on-chip light splitting to reference sensors, gives the best refractive-index limit of detection reported for planar ring resonator sensors., QC 20150421

QC 20111118. Poster presentation.

This article describes the first demonstration of ring resonators based on vertical multiple-slot silicon nitride waveguides. The design, fabrication and measurement of multiple-slot waveguide ring resonators with several coupling distances and ring radii (70 μm, 90 μm and 110 μm) have been carried out for TE and TM polarizations at the wavelength of 1.3 μm. Quality factors of 6,100 and 16,000 have been achieved for TE and TM polarization, respectively.

High efficiency surface grating couplers for silicon nitride waveguides have been designed, fabricated, and characterized. Coupling efficiencies exceeding 60 % are reported at a wavelength of 1.31 μm, as well as angular and wavelength -3 dB tolerances of 4° and 50 nm, respectively. When the wavelength is increased from 1310 nm to 1450 nm the coupling efficiency progressively decreases but remains above 20 % at 1450 nm. The influence of the duty ratio of the grating has also been investigated: maximum coupling efficiency was obtained at 50 % duty ratio.

We have experimentally demonstrated high Q-factors strip waveguide resonators using the Si3N4/SiO2 material platform at the wavelength of 1.31μm. The analyzed filters demonstrate high quality factors reaching 133,000. The dependence on resonator radii and coupling gap is also discussed.

This article describes the first demonstration of ring resonators based on vertical multiple-slot silicon nitride waveguides. The design, fabrication and measurement of multiple-slot waveguide ring resonators with several coupling distances and ring radii (70 mu m, 90 mu m and 110 mu m) have been carried out for TE and TM polarizations at the wavelength of 1.3 mu m. Quality factors of 6,100 and 16,000 have been achieved for TE and TM polarization, respectively., QC20100715

We demonstrate label-free molecule detection by using an integrated biosensor based on a Si3N4/SiO2 Slot-waveguide microring resonator. Bovine serum albumin (BSA) and anti-BSA molecular binding events on the sensor surface are monitored through the measurement of resonant wavelength shifts with varying biomolecule concentrations. The biosensor exhibited sensitivities of 1.8 and 3.2 nm/(ng/mm(2)) for the detection of anti-BSA and BSA, respectively. The estimated detection limits are 28 and 16 pg/mm(2) for anti-BSA and BSA, respectively, limited by wavelength resolution., QC20100715

The group index, instead of the effective index, is used to analyze the performance of a Si(3)N(4)-SiO(2) slot-waveguide microring refractive index sensor [Opt. Lett. 32, 3080 (2007)]. Assuming that the slot is fully filled with liquid, excellent agreement is found between experimental results and calculations., QC 20190215

We present a procedure to reconfigure microring resonators based on liquid surface adhesion. Droplets of organic solvents were deposited over Si3N4/SiO2 strip- and slot-waveguide ring resonators, and the transmission spectra were measured several hours after the evaporation of the droplets at room temperature. Our measurements show that the optical properties of the microrings are significantly modified by liquid adhered to the waveguides, persisting even 96 h after bulk evaporation. Liquid-solid interfacial forces slow down liquid evaporation at the nanoscale, enabling permanent photonic configurations. Rewriteability is achieved by removing the adhered liquid with heat., QC 20100525, Sabio

Poster. QC 20111117., SABIO

QC 20111123. Oral presentation.