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In 2019, IRnova launched a full-scale production of a reduced size, weight and power integrated detector dewar cooler assemblies (Oden MW; VGA format with 15 μm pixel pitch) covering the full mid-wavelength infrared spectral domain (3.7 μm – 5.1 μm). Oden MW exhibits excellent performance with operating temperatures up to 110 K at F/5.5 with typical values of temporal and spatial noise equivalent temperature of 22 mK and 7 mK, respectively, and an operability higher than 99.85%. More recently, IRnova developed a new detector design with a cut-off wavelength of 5.3 μm which can potentially allow an operating temperature of the detector up to 150K with excellent performance demonstrated on single pixels with a quantum efficiency as high as 46% at 4 µm without antireflection coating, a turn on bias lower than -100 mV and a dark current density as low as 8 × 10-6 A/cm2, which is a factor of < 5 higher than Rule07. The dark current was also found independent of the device size ranging from 10 μm to 223 μm indicating that surface leakage currents are not limiting the dark current. The achievable operating temperature of an FPA made of this new detector design has been estimated to be

Midwave infrared (MWIR) type-II superlattices (T2SL) have revolutionized the market with possibility of low Size, Weight and Power (SWaP) detectors. IRnova currently has a full-scale production of SWaP T2SL detectors (Oden MW, 640×512 on 15μm pitch), which have demonstrated excellent performance for operating temperatures up to 110 K at F/5.5. Development of high-resolution detectors with small pixel pitch (HD, 1280×1024 pixels) for MWIR as well as long wave and very long wave infrared (LWIR/VLWIR) detection is currently ongoing. In this paper, it has been demonstrated that the low dark current density and high sensitivity needed for high operating temperatures are maintained also for these small pixel pitch detectors, which makes IRnova’s T2SL technology fully compatible with next generation HD detectors.

QWIPs are renowned for unmatched image uniformity and stability. Still, in popular belief they are often associated with only stationary platforms due to low operating temperature and quantum efficiency. Challenging this myth, we demonstrate the performance of VLWIR QWIP in such demanding applications as handheld camera for gas detection and microsatellite for remote sensing. In the former, NETD of

In this paper, the performance of small, lightweight, and low power (SWaP) midwave infrared (MWIR) type-II superlattice detectors have been studied. The detectors cover the MWIR range from 3.7 μm to 5.1 μm with quantum efficiency higher than 60% in the entire range. Statistics from the focal plane array (FPA) production show excellent reproducibility with average temporal NETD of 20 mK, spatial NETD of 5 mK and operability values typically higher than 99.85%. Good uniformity across the arrays is demonstrated with narrow NETD histograms and highly uniform gain-correction maps. Temperature studies of the FPA performance show that the low NETD values, good uniformity and high operability are maintained up to 110 K. After integration of these FPAs in SWaP integrated detector dewar cooler assemblies (IDDCAs) with F/5.5, the high FPA performance is maintained with good imaging properties.

The III-V material system has proven to be a solid base for building infrared detector focal plane arrays (FPAs), enabling well-established designs such as bulk InSb-photodiodes, GaAs-based quantum well infrared photodetectors (QWIP) and GaSb-based type-II superlattices (T2SL). The remarkable advancement in the sensitivity and stability of such FPAs seen in the past decades calls for revision of the merits and the acceptance criteria used for the performance evaluation of infrared imaging arrays. Specifically, the early skepticism toward QWIP has largely been focused on their low quantum efficiency, and consequently low specific detectivity of the FPA pixels, as compared to the counterparts with bulk design. It was later demonstrated that unrivalled spatial uniformity of QWIP arrays (typically with a residual non-uniformity

In this paper, results from the development of InAs/GaSb superlattice focal plane arrays (FPAs) at IRnova will be presented. A versatile and robust detector design is used that allows for adjustment of the detection cut-off wavelength from 2.5 μm up to 14.5 μm with only minor changes in the detector design. Performance of the fabricated detectors has been reviewed in terms of external quantum efficiency (EQE), dark current and noise for three designs with cut-off wavelengths of 4, 5.5 and 11 μm at 80 K (referred to as DEEP BLUE, RED HOT and VLWIR, respectively). Measurements on the 15 μm sized photodiodes demonstrated 70% EQE for the MWIR designs, and almost 40% - for VLWIR. At the same time, the dark current stayed close to the Rule07 benchmark for all studied samples. Noise mechanisms have been discussed and their relation to the passivation was examined. Mature in-house processing and passivation technique of resulted in very high spatial uniformity of VGA focal plane arrays (FPAs), i.e. low relative deviations of EQE (< 6%) and of dark current density (< 12%) and narrow noise distributions for both RED HOT and DEEP BLUE FPAs. We show also that

In this paper, the performance of high operating temperature (HOT) type-II superlattice FPAs (640 × 512 pixels @ 15 μm pitch), are demonstrated. The type-II superlattice design used for these FPAs has a cut-off wavelength of 5.3 μm and the quantum efficiency is extracted to 80% at FPA level. The HOT FPAs are integrated in IDDCAs with small size, weight and power (SWaP) with F#4 configuration. Excellent imaging performance is demonstrated at 110 K with temporal NETD of 21 mK, spatial NETD of 7 mK, 10 ms integration time and typical operability > 99.8 %. From modelling and studies of the temperature dependence of the FPA performance, further increase of the operating temperature up 130 K is predicted for the 5.3μm design.

Poly-(3-hexylthiophene) (P3HT) has been applied in many fields such as organic solar cells, printed electronic circuits, due to superior semiconducting properties compared to other semiconducting p ...

In this work, wafer-scale 4H- and 6H-SiC lateral and vertical Schottky UV photodetectors (PDs) and arrays were fabricated, characterized and compared. The lateral type device was configured as a metal-semiconductor-metal (MSM) photodetector with different finger electrode widths and spacing between the fingers. The vertical type devices were formed utilizing the MSM electrodes as a top contact and a Ni contact on the wafer backside. Both types of device were fabricated on the same wafer, as seen in the abstract figure, where the transparent part of the wafer contains lateral devices and the opaque part contains vertical devices. This enables a direct comparison of the performance of the different devices types. The best fabricated PDs exhibited a UV to dark current ratio of about five orders of magnitude. The dark current was measured to be about 100 fA (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Single-crystalline zinc oxide (ZnO) nanorods (NRs) have been synthesized through a chemical bath deposition method. Their diameter is about 80 nm, and their length range from 1 µm to 7 µm can be controlled by growth time. Formation of nanoflower arrays composed of nanorods has been also achieved utilizing a standard micro-fabrication technique. Two types of ZnO nanorods devices are detailed to demonstrate their optoelectronic applications.

ZnO nanorods (NRs) sensors utilizing hybrid or monolithic integration of the NRs on nanoscale or microscale interdigitated electrodes (IDEs) were fabricated and characterized. The IDEs with their finger electrode width ranging from 50 nm to 3 µm were formed on SiO 2 /Si substrates by nanoimprint lithography or conventional photolithography and metallization techniques, whereas the ZnO NRs were grown by chemical synthesis method. The average diameter of the ZnO NRs is about 100 nm, and their length can be varied from 2 to 5 µm by controlling growth time. When sensing targets, such as molecules or nanoparticles, bind onto the ZnO NRs, the conductance between IDEs will change. As probing test, II-VI quantum dots (QDs) were attached on the ZnO NRs, and clear responses were obtained by measuring and comparing current–voltage (I-V ) characteristic of the sensor be fore and after binding the QDs. Keywords: ZnO nanorods, chemical synthesis, interdigitated electrodes and nanoimprint lithography