The Hawaii-4RG near-infrared detectors offer several output configurations in which the detectors can be interfaced with the European Southern Observatory cryogenic preamplifiers. The buffered mode of output operation has the advantages of higher speed and lower electrical crosstalk between the outputs, reduced unit cell current, etc. One of the effects of the buffered mode operation is increased glow at the bottom of the array due to the operation of the output buffers compared to the unbuffered mode. The excess glow can be a limiting source to achieve low noise in long integrations using the up-the-ramp sampling readout mode. The glow can be significantly reduced by optimally biasing the output buffer stages. This work presents the output buffer glow issue, its quantification in terms of glow per read, glow per unit integration time, its dependency on pixel speed, and its mitigation by optimization of buffered mode operation.

The Nancy Grace Roman Space Telescope project is NASA's next flagship a strophysics mission t o s tudy dark energy, dark matter, and exoplanets along with the innumerable topics that will be enabled by the infrared survey telescope's Wide Field Instrument and Coronagraph Instrument. The Wide Field Instrument contains a focal plane of 18 newly developed Teledyne H4RG-10 HgCdTe detectors. The focal plane along with Roman's ASIC for Control And Digitization of Imagers for Astronomy (ACADIA) and the focal plane electronics that power them comprise the focal plane system. Roman's focal plane completed its first s ystem l evel thermal vacuum test at NASA Goddard in 2022, when an increase in dark current compared to component level testing was observed for several detectors. Roman chartered an anomaly review board (ARB) and in collaboration with Teledyne undertook a testing program to help identify possible root cause and select from Roman's spare inventory suitable replacement detectors for devices that had significantly d egraded. A p ossible root c ause was determined by the ARB along with recommendations for how to prevent further degradation. Three detectors were replaced in Roman's focal plane, and results from the following focal plane system thermal vacuum test, implementing recommendations from the ARB, demonstrate improved dark current performance. We summarize the initial observation of the detector anomaly, present the detector testing strategy to find s uitable spares and provide evidence of root cause, share the general findings of the ARB, and show new data showing the improved dark current performance.

The composite image shows highlights of select papers from the Proceedings of the Scientific Detector Workshop 2022. From top left, clockwise : The Euclid NISP Near‐Infrared Focal Plane under test at the CEA/LAM facility in Marseilles, France (see J. Beletic et al ., e230136); The Acuros CQD sensors from SWIR Vision Systems (see C. Mackay, e230104); The Original lab book entry made at Bell Labs by Willard S. Boyle and George E. Smith on October 19th, 1969 (see M.M. Roth, e230066); The focal plane of the Dark Energy Survey (see S.E. Holland, p. xx4); The DECam CCD wafer (see S.E. Holland, e230072); The 2048 × 2048 detector array of JWST NIRCam supplied by Teledyne (see G. Rieke, e230065); Mosaic of three integrated FPA + Linear variable filters (see, J. Beletic et al ., e230136 ). image

Teledyne Imaging Sensors (TIS) is the leading supplier of infrared focal plane arrays (FPAs) to astronomy and TIS plays a strong role in providing image sensors for Earth and Planetary Science. This article starts with a brief introduction to TIS' technologies and image sensor products. We then present some of TIS' deliveries to space missions and ground-based telescopes. The space missions include ESA's Euclid Dark Universe mission and several NASA missions (James Webb Space Telescope, Roman Space Telescope, SPHEREx, EMIT). TIS continues to serve ground-based astronomy by providing the H2RG and the world's largest high-performance infrared astronomy FPA, the H4RG-15, to several ground-based observatories. Active programs will be described. Ongoing work includes NASA's NEO Surveyor asteroid surveillance mission, ESA's Ariel exo-planet spectroscopy mission, and deliveries to the European Southern Observatory's Extremely Large Telescope.

In this paper, we present the test results of a flight-grade 13μm pixel pitch 6000-element 1.7μm InGaAs linear array in a hermetic package, designed and developed for space remote sensing and imaging applications. The array consists of a single 13μm pixel pitch 6000-element InGaAs linear array and a custom single digital 2.0 Mecapacitance trans-impedance amplifier (CTIA) readout integrated circuit (ROIC) with four gains. We have achieved greater than 80% peak quantum efficiency and higher than 1100 signal-to-noise ratio (SNR) at 90% well fill. The focal plane array is in a vacuum hermatically sealed package with an anti-reflective (AR)-coated Sapphire window and 29 pins, including four for low voltage differential signaling (LVDS) outputs.

The CHROMA (Configurable Hyperspectral Readout for Multiple Applications) is an advanced Focal Plane Array (FPA) designed for visible-infrared imaging spectroscopy. Using Teledyne’s latest substrateremoved HgCdTe detector, the CHROMA FPA has very low dark current, low readout noise and high, stable quantum efficiency from the deep blue (390nm) to the cutoff wavelength. CHROMA has a pixel pitch of 30 microns and is available in array formats ranging from 320×480 to 1600×480 pixels. Users generally disperse spectra over the 480 pixel-length columns and image spatially over the n×160 pixellength rows, where n=2, 4, 8, 10. The CHROMA Readout Integrated Circuit (ROIC) has Correlated Double Sampling (CDS) in pixel and generates its own internal bias signals and clocks. This paper presents the measured performance of the CHROMA FPA with 2.5 micron cutoff wavelength including the characterization of noise versus pixel gain, power dissipation and quantum efficiency.

Teledyne Imaging Sensors develops and produces high performance silicon-based CMOS image sensors, with associated electronics and packaging for astronomy and civil space. Teledyne's silicon detector sensors use two technologies: monolithic CMOS, and silicon PIN hybrid CMOS. Teledyne's monolithic CMOS sensors are large (up to 59 million pixels), low noise (2.8 e- readout noise demonstrated, 1-2 e- noise in development), low dark current (<10 pA/cm2 at 295K) and can provide in-pixel snapshot shuttering with >103 extinction and microsecond time resolution. The QE limitation of frontside-illuminated CMOS is being addressed with specialized microlenses and backside illumination. A monolithic CMOS imager is under development for laser guide star wavefront sensing. Teledyne's hybrid silicon PIN CMOS sensors, called HyViSITM, provide high QE for the x-ray through near IR spectral range and large arrays (2K×2K, 4K×4K) are being produced with >99.9% operability. HyViSI dark current is 5-10 nA/cm2 (298K), and further reduction is expected from ongoing development. HyViSI presently achieves <10 e- readout noise, and new high speed HyViSI arrays being produced in 2008 should achieve <4 e- readout noise at 900 Hz frame rate. A Teledyne 640×480 pixel HyViSI array is operating in the Mars Reconnaissance Orbiter, a 1K×1K HyViSI array will be launched in 2008 in the Orbiting Carbon Observatory, and HyViSI arrays are under test at several astronomical observatories. The advantages of CMOS in comparison to CCD include programmable readout modes, faster readout, lower power, radiation hardness, and the ability to put specialized processing within each pixel. We present one example of in-pixel processing: event driven readout that is optimal for lightning detection and x-ray imaging.

Inter-Pixel capacitance (IPC) is an effect that can occur in bump-bonded hybrid CMOS pixel arrays that employ a source follower pixel amplifier. IPC can result in the signal in one pixel being sensed by adjacent pixels that are capacitively coupled. IPC effect is more pronounced in full-depletion silicon hybrid CMOS focal plane arrays than infrared arrays because of the stronger coupling path through the silicon detector layer. IPC can degrade the image resolution and it can cause an overestimation of conversion gain (electrons per mV) determined from conventional photon-transfer method because the IPC "blur" reduces the variance of photon noise. However, the IPC effect can be minimized with improvements in pixel design, and the conversion gain can be properly calculated, and image resolution can be restored with deconvolution techniques. In this paper, we report the results of a recent effort to reduce IPC in Teledyne's visible silicon hybrid CMOS focal plane arrays through pixel design improvements.