Over a decade has passed since complementary metal oxide semiconductor (CMOS) imaging detectors made their move into the charge-coupled device (CCD) arena. Low cost, low power, on-chip system integration, high-speed operation and tolerance to high-energy radiation sources are unique features that make CMOS detectors popular. However, it remains unclear if CMOS arrays can compete with the CCD in high performance applications (e.g., scientific). This paper compares fundamental performance parameters common to both CMOS and CCD imagers, and lists specific SMOS performance deficiencies that prevent the technology from high end use. In this paper we will present custom CMOS pixel designs and related fabrication processes that solve most deficiencies. We will also discuss "hybrid" imaging arrays that marry the advantages of CCD and CMOS producing sensors with superior performance in comparison to CCD and CMOS bulk monolithic sensors. CCD to CMOS, CMOS to CMOS and CMOS SOI hybrids are reviewed.
Recent advances in astronomical research have led to a much-improved understanding of the evolution of the physical Universe. Recent advances in biology and genetics have led to a much-improved understanding of our biological Universe. Scientists now believe that we have the research tools to begin to answer one of man’s two most compelling research questions: "are we alone?" and "how did we get here?" This paper reviews the requirements and challenges we
face to engineer and build the large area and very sensitive focal planes for interferometers and innovative single aperture telescopes to detect and characterize Earth-type planets around stars other than our sun.
The SEU theme encompasses an extremely diverse area of space science. Recent roadmapping efforts been devoted to prioritizing science challenges rather than defining all that is contained in the SEU theme. The highest priorities are the Big Bang and a look at Black Holes and the regions near them.
To support these challenges the following technologies are of high priority: Cryogenic Systems, Formation Flying, High Performance Optics: Mid- and Far-IR Optics, X-Ray/UV optics, Advanced Detectors: X-ray and Submm/Far IR, Energy resolving detectors and Large Format Arrays.
The initiative, Beyond Einstein, includes baseline missions that utilize technologies that are generally at a laboratory proof of concept level. Technology development plans are established for the flagship missions: Con-X and LISA. Conceptual development is still progressing for some Einstein Probe missions. Vision missions are still in conceptual development.
In November 2003, a Space Environmental Effects Working Group meeting in El Segundo, CA developed technology roadmaps and recommended Government investment strategies for key technologies needed for large space imaging systems. This paper summarizes results from the session on focal plane array (FPA) technology. The FPA session
recommended continued emphasis and additional investments to strengthen the manufacturing infrastructure for production and test of advanced focal planes and readouts, especially those operating at cryogenic temperatures and in radiation environments.
The ESA cornerstone mission GAIA will perform astrometric and photometric measurements on one billion objects, and is due for launch in 2010 into L2 orbit. The key astrometric focal plane will comprise over 180 large area CCDs with a focal surface of about 0.5m2. The 45x60mm2 CCDs for the focal plane will include technical features new to CCDs. This paper will discuss the characteristics of these devices, including the measures to improve the radiation hardness of the technology.
An overview of CCD development efforts at Lawrence Berkeley National
Laboratory is presented. Operation of fully-depleted, back-illuminated CCD's fabricated on high resistivity silicon is described, along with results on the use of such CCD's at ground-based observatories. Radiation damage and point-spread function measurements are described, as well as discussion of CCD fabrication technologies.
The primary mission of the upcoming HiRISE instrument on the Mars Reconnaissance Orbiter spacecraft is to better
understand the geologic and climatic processes on Mars and to evaluate future landing sites. To accomplish this goal, a high resolution space-based camera is being developed that employs a 0.5m aperture Cassegrain-type telescope coupled to a large focal plane array (FPA) measuring approximately 14" (L) x 2" (W) x 2" (D). The FPA is populated with 14 time delay and integrate (TDI) format custom charge-coupled device (CCD)-based detectors. The FPA includes
panchromatic, near infrared, and blue-green spectral channels. The panchromatic channel has 20,000 pixels in the cross track direction. Each color channel consists of 4,000 pixels in the cross track direction. The minimum ground sampling distance of all channels is 50 cm per pixel. The instrument’s instantaneous field of view is 1.43o x 0.1o. Over the 5-year mission, the FPA will map a portion of the surface of Mars with high spatial resolution and high signal-to-noise
ratio (>100:1 at all latitudes). Electronics are housed immediately behind the FPA, which yields a low noise, compact
design that is both robust and fault tolerant. Test and characterization data from the FPA and custom CCD-based detectors is discussed along with the results from performance models.
e2v technologies has demonstrated capability in the supply of state-of-the-art CCDs for large area scientific focal planes. We discuss technical developments and lessons learnt from the manufacture and supply of large-format CCDs. Several large mosaics have now been built or are under construction, using e2v sensors- these include CFHT Megacam, ESO VST, SAO Megacam, Kepler, and GAIA. Design, assembly and operational issues are presented.
Silicon-based hybrid CMOS focal plane array technology offers many advantages needed for both ground-based and space imaging applications. These advantages include enhanced UV and NIR sensitivity, extensive on-chip readout capability, inherent radiation hardness, flexible imaging readout and the ability to provide extremely low noise at high video rates. For infrared imaging applications that involve UV-through visible channels, the readout electronics commonality facilitates a great simplification to system designs. In this paper, Rockwell Scientific CMOS-based hybrid silicon FPA technology and the recent progress are presented. The hybrid FPAs developed include 640x480, 1024x1024 and 2048x2048 formats with pixel sizes ranging from 27μm to 18μm square, featuring a high optical fill factor (~100%), broad-band response (200nm to 1000nm) with high quantum efficiency, and low read noise (<6e-) that approaches astronomy CCDs at 100KHz video rate and surpasses astronomy CCDs at 1MHz rate. Other performance parameters, such as spatial uniformity, dark current, pixel crosstalk/MTF and CMOS features are also discussed.
Charge Injection Devices (CIDs) have historically played a niche role in visible imager technologies, mainly for applications requiring high radiation tolerance. They have not exhibited the radiometric performance of competing visible- imaging technologies such as CCDs, and so have not been widely applied to space instrument systems. Recent advances in CIDs have demonstrated much higher radiometric performance as well as lower noise operation, without compromising the radiation tolerance of the devices, making the devices suitable for a wide range of space instruments. We present radiometric, noise, and radiation response data for several of the newest CID designs that are candidate technologies for visible space telescope systems.
A comparative study between radhard-by-design and radhard-by-foundry approaches for radiation hardening of CMOS imagers is presented. Main mechanisms for performance degradation in CMOS imagers in a radiation environment are identified, and key differences between the radiation effects in CMOS imagers and that in digital logic circuits are explained. Design methodologies for implementation of CMOS imagers operating in a radiation environment are presented. By summarizing the performance results obtained from imagers implemented in both radhard-by-design and radhard-by-foundry approaches, the advantages and shortcomings of both approaches are identified. It is shown that neither approach presents an optimum solution. The paper concludes by discussing an alternate pathway to overcome these limitations and enable the next-generation high-performance radiation-hard CMOS imagers.
Mechanisms for noise coupling in CMOS imagers are complex, since unlike a CCD, a CMOS imager has to be considered as a full digital-system-on-a-chip, with a highly sensitive front-end. In this paper, we analyze the noise sources in a photodiode CMOS imager, and model their propagation through the signal chain to determine the nature and magnitude of noise coupling. We present methods for reduction of noise, and present measured data to show their viability. For temporal read noise reduction, we present pixel signal chain design techniques to achieve near 2 electrons read noise. We model the front-end reset noise both for conventional photodiode and CTIA type of pixels. For the suppression of reset noise, we present a column feedback-reset method to reduce reset noise below 6 electrons. For spatial noise reduction, we present the design of column signal chain that suppresses both spatial noise and power supply coupling noise. We conclude by identifying problems in low-noise design caused by dark current spatial distribution.
ImagerLabs has advanced its patented next generation imaging technology called the Hybrid Imaging Technology (HIT) that offers scientific quality performance. The key to the HIT is the merging of the CCD and CMOS technologies through hybridization rather than process integration. HIT offers exceptional QE, fill factor, broad spectral response and very low noise properties of the CCD. In addition, it provides the very high-speed readout, low power, high linearity and high integration capability of CMOS sensors. In this work, we present the benefits, and update the latest advances in the performance of this exciting technology.
Readout noise levels of under 1 electron have long been a goal for the FPA community. In the quest to enhance the FPA sensitivity, various approaches have been attempted ranging from the exotic Photo-multiplier tubes, Image Intensifier tubes, Avalanche photo diodes, and now the on-chip avalanche charge amplification technologies from the CCD manufacturers. While these techniques reduce the readout noise, each offers a set of compromises that negatively affect the overall performance of the sensor in parameters such as power dissipation, dynamic range, uniformity or system complexity.
In this work, we overview the benefits and tradeoffs of each approach, and introduce a new technique based on ImagerLabs’ exclusive HIT technology which promises sub-electron read noise and other benefits without the tradeoffs of the other noise reduction techniques.
The demand for large-format NIR arrays has grown for both ground-based and space-based applications. These arrays are required for maintaining high resolution over very large fields of view for survey work. We describe results of the development of a new 2048 x 2048 HgCdTe/CdZnTe array with 20-micron pixels that responds with high quantum efficiency over the wavelength range 0.85 to 2.5 microns. With a single-layer anti-reflection (AR) coating, the responsive quantum efficiency is expected to be greater than 85% from 0.9 micron to 2.4 microns. The modular package for this array, dubbed the VIRGO array, allows three-side butting to form large mosaic arrays of 4K x 2nK format. The VIRGO readout integrated circuit (ROIC) utilizes a Source Follower per Detector (SFD) input circuit with a well capacity of about 2 x 105 electrons and with a read noise of less than 20 e-rms with off-chip Correlated Double Sampling (CDS). Other features of the VIRGO array include 4 or 16 outputs (programmable), and a frame rate of up to 1.5 Hz in 16-output mode. Power dissipation is about 7 mW at a 1 Hz frame rate. Reset modes include both global
reset and reset by row (ripple mode). Reference pixels are built-in to the output data stream.
The first major application of the VIRGO array will be for VISTA, the United Kingdom’s Visible and Infrared Survey Telescope for Astronomy. The VISTA FPA will operate near 80K. Dark current is less than 0.1e-/sec at 80K. The cutoff wavelength of the HgCdTe detector can be adjusted for other applications. Space applications might include
SNAP, the Supernova/Acceleration Probe, which requires a shorter detector cutoff wavelength of about 1.7 microns. For applications which require both visible and NIR response, the detector CdZnTe substrate can be removed after hybridization, allowing the thinned detector to respond to visible wavelengths as short as 0.4 microns.
The James Webb Space Telescope (JWST), the successor to the Hubble Space Telescope, will draw on recent improvements in infrared array technologies to achieve its goals and mission. In order to best meet the goals of JWST, NASA is funding a competition between two near infrared detector technologies: InSb detector arrays from Raytheon Vision Systems and HgCdTe detector arrays from Rockwell Scientific. The University of Rochester, in collaboration with Raytheon, is testing near infrared InSb detectors in a 2048 x 2048 array format
to meet the stringent requirements for JWST. Results from characterization under top level requirements, such as noise, quantum efficiency, well capacity, pixel operability, etc., are discussed. Dark current and its contribution to the total noise are analyzed.
The advanced planar ion-implantation-isolated heterojunction process, which utilizes the benefits of both the boron implantation and the heterojunction epitaxy techniques, has been developed and used to produce longwave and very longwave HgCdTe focal plane arrays in the 320v256 format. The wavelength of these arrays ranges from 10.0-17.0μm. The operability of the longwave HgCdTe arrays is typically over 97%. Without anti-reflection coating and with a 60° FOV cold shield, the D* of the 10.0μm array is 9.4x1010cm x (Hz)1/2 x W-1 at 77K. The 14.7μm and 17.0μm very longwave HgCdTe array diodes have excellent reverse characteristics. The detailed characteristics of these arrays are presented.
Wide Field Camera 3 is a fourth generation instrument for the
Hubble Space Telescope (HST), to be installed during the next HST Servicing Mission 4. For its infrared channel Rockwell Scientific Company has developed a new type of HgCdTe 1Kx1K detector, called WFC3-1R, with cutoff wavelength at 1.7μm and 150K operating temperature. The WFC3-IR detectors are based on HgCdTe MBE grown on a CdZnTe substrate and use a new type of multiplexer, the Hawaii-1R
MUX. Two flight detectors, a prime and a spare, have been recently selected on the basis of the measures performed at NASA Goddard Research Center - Detector Characterization Laboratory. These parts show quantum efficiency higher than 80% at λ=1.6μm and greater than 40% at λ>1.1μm, readout noise of ~25 e- rms with double correlated sampling, and mean dark current of ~0.04 e/s/pix at 150K. We show that the IR channel of WFC3, equipped with one of these flight detectors, beats the instrument requirements in all configurations and promises to have a discovery efficiency
significantly higher than NICMOS. In particular, a two-band
wide-area, deep survey made with WFC3 exceeds the discovery
efficiency of NICMOS before and after the installation of NCS
by a factor of 15 and 10, respectively.
In the on-going evolution of GaAs Quantum Well Infrared Photodetectors (QWIPs) we have developed a 1,024 x 1,024 (1K x 1K), 8.4-9 μm infrared focal plane array (FPA). This 1 megapixel detector array is a hybrid using the Rockwell TCM 8050 silicon readout integrated circuit (ROIC) bump bonded to a GaAs QWIP array fabricated jointly by engineers at the Goddard Space Flight Center (GSFC) and the Army Research Laboratory (ARL). The finished hybrid is thinned at the Jet Propulsion Lab. Prior to this development the largest format array was a 512 x 640 FPA. We have integrated the 1K x 1K array into an imaging camera system and performed tests over the 40K-90K temperature range achieving BLIP performance at an operating temperature of 76K (f/2 camera system). The GaAs array is relatively easy to fabricate once the superlattice structure of the quantum wells has been defined and grown. The overall arrays costs are
currently dominated by the costs associated with the silicon readout since the GaAs array fabrication is based on high yield, well-established GaAs processing capabilities. In this paper we will present the first results of our 1K x 1K QWIP array development including fabrication methodology, test data and our imaging results.
The Orion program developed a 2048x2048 infrared focal plane using InSb PV diodes for detectors. Several of these focal planes have been produced. However, the yield of the original readout multiplexer was not up to expectations owing to unanticipated shorts in the fabrication process. Since these shorts occurred at the metal 1-metal 2 crossover points and there are over 9 million such crossovers, the design had to be modified to work around these problems. Thus the Orion II readout was developed. The work is being done at the Raytheon Vision Systems (RVS) division (most recently Raytheon Infrared Operations, but better known as SBRC) by many of the same people who created the Orion I and ALADDIN focal planes. The design is very similar to the Orion I design with the addition of circuitry to work around the effect of the metal 1-metal 2 shorts. In this paper we will discuss the unique design features of this device as well as present test data taken from the new devices.
Inter-pixel capacitive coupling can exist in a non-destructive detector array if the detector nodes change voltage as they integrate charge and the design of the device allows for an electric field to exist between adjacent collection nodes. Small amounts of inter-pixel capacitance can cause large errors in the measurement of poissonian noise versus signal, and all subsequently derived measurements such as nodal capacitance and quantum efficiency. Crosstalk and MTF can also be significantly influenced by interpixel capacitance. Two 1k by 1k Raytheon SB226-based hybridized silicon PIN arrays were tested for nodal capacitance and MTF. Initial results indicated unexpected and unexplainably large nodal capacitance, poor MTF, and odd edge spread. It was hypothesized that inter-pixel capacitive coupling was responsible for these discrepancies. A stochastic method of measuring the coupling using 2D autocorrelation and Fourier Transform techniques was devised and implemented. Autocorrelation of the shot noise in the images revealed a correlation consistent with 3.2% interpixel capacitive coupling. When the effects of the measured interpixel capacitance were taken into account, the initially measured nodal capacitance of 56 fF was found to be 31% higher than the corrected nodal capacitance measurement of 43 fF. Large discrepancies between the theoretical and observed edge spread response were also greatly reduced. A simulation of the electric field in the PIN detector intrinsic region predicted an interpixel coupling very close to the observed coupling. Interpixel capacitance was also observed in a 2k by 2k Raytheon SB304-based InSb detector array, but was not strongly evident in a bare Raytheon SB226 multiplexer.
The Defense Threat Reduction Agency (DTRA) and National Aeronautics and Space Administration (NASA) Goddard Space Flight Center are collaborating to develop the Carrier Plus sensor experiment platform as a capability of the Space Environment Testbed (SET). The Space Environment Testbed (SET) provides flight opportunities for technology
experiments as part of NASA's Living With a Star (LWS) program. The Carrier Plus will provide new capability to characterize sensor technologies such as state-of-the-art visible focal plane arrays (FPAs) in a natural space radiation environment. The technical objectives include on-orbit validation of recently developed FPA technologies and sensor performance prediction methodologies, as well as characterization of the FPA radiation response to total ionizing dose damage, displacement damage and transients. It is expected that the sensor experiment will carry 4-6 FPAs and associated radiation correlative environment monitors (CEMs) for a 2008 launch. Sensor technology candidates may include n- and p-charge coupled devices (CCDs), active pixel sensors (APS), and hybrid CMOS arrays. This paper will describe the Carrier Plus goals and objectives, as well as provide details about the architecture and design. More information on the LWS program can be found at http://lws.gsfc.nasa.gov/
gov/. Business announcements for LWS/SET and program briefings are posted at http://lws-set.gsfc.nasa.gov.
As the logical extension of the 20-year mission of the Hubble Space Telescope, NASA plans to launch the James Webb Space Telescope (JWST, formerly NGST) near the end of this decade. As Hubble's scientific and technological successor, equipped with a 6-meter-class deployable mirror, JWST will allow observations of the very early universe
and initial formation of galaxies at levels not achievable today. JWST's unprecedented sensitivity cannot be utilized without a new class of IR focal plane arrays whose performance matches that of the telescope. In particular, JWST focal planes must be able to withstand the ionizing-particle radiation environment expected for its Lagrange-point (L2) orbit and ten-year mission lifetime goal. To help determine their suitability for JWST, NASA is evaluating prototype
megapixel-class readouts and hybrid detector arrays under proton bombardment to simulate the anticipated JWST lifetime radiation dose. This report describes the results of early tests on devices from two manufacturers using photovoltaic (HgCdTe or InSb) candidate near-infrared detector structures. Results to date have shown encouraging
performance, along with some areas of continuing concern.
The Advanced camera for Surveys (ACS), installed in the Hubble Space telescope in March 2002, has significantly extended HST’s deep, survey imaging capabilities. ACS comprises three cameras: the Wide Field Camera (WFC) is designed for deep, near-IR survey imaging programs; the High Resolution Camera (HRC) is a high angular resolution imager/coronagraph, which fully samples the HST point spread function in the visible; and the Solar Blind Camera (SBC) is a far-UV imager. ACS has met, or exceeded all of its key performance specification. In this paper we briefly review the in-flight performances of the instrument's CCD detectors. We present an overview of the performance of the ACS CCD detectors, based on the first year of flight science operations.
A Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) flight-like IR detector was tested for radiation hardness by exposing it to high energy protons while operating at the nominal flight temperature of 150 K. The detector is a 1.7 μm cutoff HgCdTe detector with a CdZnTe substrate. The device is hybridized to a silicon multiplexer. The detector response was tested for gradually increasing fluence from less than 1x103 to a total of 5x109 63 MeV protons/cm2. Dark current changes were evaluated after each step. An increase in dark current and new hot pixels were observed after large steps of irradiation. The increased dark current was observed to partially anneal at 190K and fully anneal at room temperature. Radiation effects, hot pixel distribution, and results of annealing at different temperatures are presented here.
A Hubble Space Telescope Wide Field Camera 3 (WFC3) CCD detector was tested for radiation effects while operating at -83°C. The detector has a format of 2048 x 2048 pixels with a 15 μm square pixel size, a supplemental buried channel, an MPP implant, and is back side illuminated. Detector response was tested for total radiation fluences ranging from 1x103 to 2.5x109 of 63.3 MeV protons/cm2 and for a
range of beam intensities. Radiation damage was investigated and the annealing of damage was tested by warming up to +30°C. The introduction rate of hot pixels and their statistics, hot pixel annealing as a function of temperature and time, and radiation changes to the mean value of dark current were investigated. Results are compared with the experiences of other HST instruments.
The Independent Detector Testing Laboratory (IDTL) is jointly operated by the Space Telescope Science Institute (STScI) and the Johns Hopkins University (JHU), and is assisting the James Webb Space Telescope (JWST) mission in choosing and operating the best near-infrared detectors. The JWST is the centerpiece of the NASA Office of Space Science theme, the Astronomical Search for Origins, and the highest priority astronomy project for the next decade, according to the National Academy of Science. JWST will need to have the sensitivity to see the first light in the Universe to determine how galaxies formed in the web of dark matter that existed when the Universe was in its infancy (z~10-20). To achieve this goal, the JWST Project must pursue an aggressive technology program and advance infrared detectors to performance levels beyond what is now possible. As part of this program, NASA has selected the IDTL to verify comparative performance between prototype JWST detectors developed by Rockwell Scientific (HgCdTe) and Raytheon (InSb). The IDTL is charged with obtaining an independent assessment of the ability of these two competing technologies to achieve the demanding specifications of the JWST program within the 0.6-5 μm bandpass and in an ultra-low background (<0.01 e-/s/pixel) environment. We describe results from the JWST Detector Characterization Project that is being performed in the IDTL. In this project, we are measuring first-order detector parameters, i.e. dark current, read noise, QE, intra-pixel sensitivity, linearity, as functions of temperature, well size, and operational mode.
High accuracy space astrometry missions such as the recently proposed AMEX will observe tens of millions of stars with mission measurement accuracies of less than 150 microarcseconds at mv = 9. In order to achieve this level of accuracy and coverage, focal planes containing tens of CCDs are necessary. These CCDs are exposed to damage from charged particles from Earth's radiation belts and solar wind. We have developed a computer simulation in order to estimate the effects of charged particle damage on the single measurement precision of an astrometric instrument in space. We describe the simulation in detail, and provide an example of its use in predicting the measurement performance of the AMEX instrument.
Future infrared space missions will undoubtedly employ passively cooled focal plane arrays (T ~ 30K), as well as passively cooled telescopes. Most long-wave detector arrays (e.g. Si:As IBC) require cooling to temperatures of ~ 6-8K. We have been working with Rockwell Scientific Company to produce ≥ 10 μm cutoff HgCdTe detector arrays that, at temperatures of ~ 30K, exhibit sufficiently low dark current and sufficiently high detective quantum efficiency, as well as high uniformity in these parameters, to be interesting for astronomy. Our goal is to achieve dark current below the target value of ~30 e-/s/pixel with at least 60mV of actual reverse bias across the diodes at T ~ 30K. To this end, Rockwell Scientific Company has delivered the first array in a new order, for characterization in Rochester. Recent array deliveries of 10μm cutoff HgCdTe bonded to a Hawaii-1RG multiplexer utilize the smallest capacitance diode type. We present preliminary results on this latest 10 μm cutoff HgCdTe low dark current detector array.
The E2V CCD42-20 NIMO type CCD was tested in view of its use for the german astrometric satellite mission DIVA. As in other astrometric missions (FAME, GAIA) the CCDs will be operated in TDI mode synchronous with the stars drifting across the detectors. At the expected operating temperature, around -30C to -50C, the dark current performance is an important parameter. Radiation induced degradations with respect to dark current and CTE are of particular concern, too.
We find that TDI operation reduces the dark current by a factor of ≈30 near the DIVA satellite TDI clock rate (1.4 msec). The detector was irradiated with soft protons, in a first run, with rather weak doses of up to an equivalent 10 MeV fluence of 1.6×108 protons/cm2. The increase in dark current is quite small (4% to 5% maximum at -40C) but seems to vary with temperature (e.g. 2% at -60C). The CTE degradation shows a linear
dependance on the radiation dose and the CTE gets worse if the detector temperature gets lower (e.g. for the highest dose: 0.999 98 at -60C and 0.999 95 at -100C). Vertical and horizontal deferred charge patterns show a significant difference. The total mission dose will be about 10x higher and the dark current and CTE values are tentatively extrapolated. The results of this study shall serve as a basis for further irradiation experiments combined with laboratory simulations and numerical modelling.
During the course of this study the DIVA project had to be stopped due to lack of funding. But our results are applicable equally well to the proposed SMEX mission AMEX which is based on the DIVA concept.
Large infrared detector arrays are now available that meet the demanding requirements of the astronomy and civil space communities. This paper describes arrays with more than one million detector elements developed by Raytheon Vision Systems for these low-background applications. These detector arrays have 1024 x 1024 and 2048 x 2048 formats with element spacing ranging from 20 to 27 μm. Arrays of this size have been demonstrated with a variety of deteector materials: Si PIN, HgCdTe, InSb, and Si:As IBC. The performance of each of these materials on arrays with more than one million detector elements is discussed. All of these detector materials have demonstrated low noise and dark current, high quantum efficiency, and excellent uniformity. All can meet the high performance requirements for low-background within the limits of their respective spectral and operating temperature ranges. Features of the readout integrated circuits that mate to these detector arrays are also discussed.
Companion papers in these SPIE proceedings that discuss several of these arrays in more detail are:
1. "Large-format 0.85 and 2.5 μm HgCdTe detctor arrays for low-background applications", P.J. Love, A. W. Hoffman, D. L. Gulbransen, K. J. Ando, M. P. Murray, N. J. Therrien
2. "James Webb Space Telescope characaterization of flight candidate NIR InSb array", C. W. McMurtry, W. J. Forrest, J. L. Pipher, A. C. Moore
3. "Orion II: the second-generation readout multiplexer for largest infrared hybrid focal plane", K. M. Merrill, A. M. Fowler, W. Ball, A. Henden, F. J. Vrba, C. McCreight
4. "Interpixel capacitance in nondestructive focal plane arrays" A. C. Moore
5. "Radiation environment performance of JWST prototype FPAs", M. E. McKelvey, K. A. Enico, R. E. McMurray Jr., R. A. Reed, C. R. McCreight
6. "Independent testing of JWST detector prototypes," D. F. Figer, B. Rauscher, M. W. Regan, J. Balleza, L. Bergeron, E. Morse, H. S. Stockman.