In recent years SCD has developed InGaAs/InP technology for Short-Wave Infrared (SWIR) imaging. The first
product, Cardinal 640, has a 640x512 (VGA) format at 15μm pitch, and more than a thousand units have already
We now present Cardinal 1280, having the smallest pitch available today (10μm), with a 1280x1024 (SXGA)
format. Cardinal 1280 addresses both long-range daylight imaging, and passive or active imaging in Low Light
Level (LLL) conditions.
The Readout Integrated Circuit supports snapshot imaging at 13 bit resolution with a frame rate of 160Hz at full
format, or a frame rate of 640Hz with 2x2 binning. It also has a Low Noise Imaging (LNIM) mode with 35ereadout
noise with internal Correlated Double Sampling (CDS). An asynchronous Laser Pulse Detection (ALPD)
mode is implemented with 2x2 binning in parallel to SWIR imaging (with 10 μm resolution). The new 10 μm
pixel is sensitive down to the visible (VIS) spectrum, with a typical dark current of ~ 0.5fA at 280K, and a
quantum efficiency >80% at 1550nm.
The Focal Plane Array is integrated into a ruggedized, high vacuum integrity, metallic package, with a Thermo-
Electric Cooler (TEC) for optimized performance, and a high grade Sapphire window. In this paper we will
present the architecture and preliminary measurement results.
When incorporated into the active layer of a "XB<i>p</i>" detector structure, Type II InAs/GaSb superlattices (T2SLs) offer a high quantum efficiency (QE) and a low diffusion limited dark current, close to MCT Rule 07. Using a simulation tool that was developed to predict the QE as a function of the T2SL period dimensions and active layer stack thickness, we have designed and fabricated a new focal plane array (FPA) T2SL XB<i>p</i> detector. The detector goes by the name of "Pelican-D LW", and has a format of 640 ×512 pixels with a pitch of 15 μm. The FPA has a QE of 50% (one pass), a cut-off of ~9.5 μm, and operates at 77K with a high operability, background limited performance and good stability. It uses a new digital read-out integrated circuit, and the integrated detector cooler assembly (IDCA) closely follows the configuration of SCD’s Pelican-D MWIR detector.
Advanced electro-optical systems are designed towards a more compact, low power, and low cost solution with respect to traditional systems. Integration of several components or functionalities, such as infrared imager, laser designator, laser range finder (LRF), into one multi-function detector serves this trend. SNIR Read-Out Integrated Circuit (ROIC) incorporates this high level of signal processing and with relatively low power consumption. In this paper we present measurement results from a Focal Plane Array (FPA) where the SNIR ROIC is Flip-Chip bonded to a 15µm pitch VGA InGaAs detector array. The FPA is integrated into a metallic vacuum sealed package. We present InGaAs arrays with dark current density below 1.5 nA/cm<sup>2</sup> at 280K (typically 1fA), Quantum Efficiency higher than 80% at 1550 nm and operability better than 99.5%. The metallic package is integrated with a low power proximity electronics which delivers Camera Link output. The overall power dissipation is less than 1W, not including Thermal-Electric Cooling (TEC), which is required in some applications. The various active and passive operation modes of this detector will be reviewed. Specifically, we concentrate on the "high gain" mode with low readout noise for Low Light Level imaging application. Another promising feature is the Asynchronous Laser Pulse Detection (ALPD) with remarkably low detection thresholds.
SCD has developed a new 1920x1536 / 10 <i>μ</i>m digital Infrared detector for the MWIR window named Blackbird. The
Blackbird detector features a Focal Plane Array (FPA) that incorporates two technological building blocks developed
over the past few years. The first one is a 10 <i>μ</i>m InSb pixel based on the matured planar technology. The second building
block is an innovative 10 <i>μ</i>m ReadOut Integrated Circuit (ROIC) pixel. The InSb and the ROIC arrays are connected
using Flip-Chip technology by means of indium bumps. The digital ROIC consists a matrix of 1920x1536 pixels and has
an analog to digital (A/D) converter per-channel (total of 1920x2 A/Ds). It allows for full frame readout at a high frame
rate of up to 120 Hz. Such an on-chip A/D conversion eliminates the need for several A/D converters with fairly high
power consumption at the system level. The ROIC power consumption at maximum bandwidth is less than 400 mW. It
features a wide range of pixel-level functionality such as several conversion gain options and a 2x2 pixel binning. The
ROIC design makes use of the advanced and matured CMOS technology, 0.18 <i>μ</i>m, which allows for high functionality
and relatively low power consumption. The FPA is mounted on a Cold-Finger by a specially designed ceramic substrate.
The whole assembly is housed in a stiffened Dewar that withstands harsh environmental conditions while minimizing the
environment heat load contribution to the heat load of the detector. The design enables a 3-megapixel detector with
overall low size, weight, and power (SWaP) with respect to comparable large format detectors. In this work we present
in detail the characteristic performance of the new Blackbird detector.
A 1920x1536 matrix ROIC (Readout IC) for 10x10 μm<sup>2</sup> P-on-N InSb photodiode array is reported. The ROIC features
several conversion gain options implemented at the pixel level. A 2-by-2 pixel binning feature is implemented at the
pixel level as well, improving SNR and enabling higher frame rates by a factor of four. A new column ADC is designed
for low noise and low power consumption, while reaching 95 kSps sampling rate. Since 3840 column ADCs are
integrated on chip, the total conversion rate is over 360Mpxl/sec. The ROIC achieves 120 Hz frame rate at the full
format, with power consumption of less than 400mW. A high speed digital video interface is developed to output the
required data bandwidth at a reasonable pin count.
Short wavelength Infra Red (SWIR) imaging has gained considerable interest in recent years. The main applications
among others are: active imaging and LADAR, enhanced vision systems, low light level imaging and security
In this paper we will describe SCD's considerable efforts in this spectral region, addressing several platforms:
1. Extension of the mature InSb MWIR product line operating at 80K (cut-off wavelength of 5.4μm).
2. Extension of our new XB<sub>n</sub><i>n</i> InAsSb "bariode" technology operating at 150K (cut-off of 4.1μm).
3. Development of InGaAs detectors for room temperature operation (cut-off of 1.7μm)
4. Development of a SNIR ROIC with a low noise imaging mode and unique laser-pulse detection modes.
In the first section we will present our latest achievements for the cooled detectors where the SWIR region is combined
with MWIR response. Preliminary results for the NIR-VIS region are presented where advanced substrate removal
techniques are implemented on flip-chip hybridized focal plane arrays.
In the second part we will demonstrate our VGA, 15μm pitch, InGaAs arrays with dark current density below 1.5nA/cm<sup>2</sup>
at 280K. The InGaAs array is hybridized to the SNIR ROIC, thus offering the capability of low SWaP systems with
laser-pulse detection modes.
Pelican-D is a new digital 640x512 / 15μm InSb detector developed by SCD to serve a number of applications. The
Readout Integrated Circuit (ROIC) has a digital output which can be calibrated to a signal resolution in the 13-15 bit
range. Besides the digital output, the detector has some additional advantages over other MWIR detectors of the same
format. The high frequency of data output, which supports a full image frame rate of over 300Hz, is very useful in
systems that track fast evolving events such as Missile Warning Systems (MWS), Missile Seekers and some
Thermographic applications. Another important characteristic of the detector is related to an operation mode with
relatively low readout noise. This mode of operation is especially beneficial in applications where the background
radiation is low such as in long range surveillance systems. For imaging systems where very high sensitivity is required,
the ROIC can be coupled to an epi-InSb detector array and have a dark current at 77K that is lower by a factor of 15 with
respect to standard InSb. Alternatively, Pelican-D with epi-InSb can be operated at 95K with a standard dark current and
sensitivity. Such an elevated operating temperature enables the use of cryogenic coolers of relatively low size, weight
and power for applications such as Hand-held cameras, miniature gimbaled systems, and light UAVs. In this work we
present in detail the characteristic performance of the new detector and its applications.
Modern electro-optical systems contain several components such as thermal imager, laser designator, laser range finder,
etc. The demand for compact systems with low power consumption and low cost can be addressed by incorporating
some of the traditional system abilities into the IR detector. We present SNIR, a new type of detector, which consists of a
Read Out Integrated Circuit (ROIC) with advanced on-chip signal processing. The ROIC is flip chip-bonded to a
640x512 InSb detector array of 15μm pitch. SNIR digital ROIC can be operated in either one of the following four
different modes of operation. The first operation mode is standard thermal imaging, which has typical functionalities and
performance of MWIR detector. The second operation mode is a dual-function mode that includes both standard thermal
imaging and information on Asynchronous Laser Pulse Detection (ALPD) for each pixel. The detection probability of a
laser pulse is significantly increased by integrating a dedicated in-pixel circuit for identifying a fast signal temporal
profile. Since each pixel has internal processing to identify laser pulses, it is possible also to measure the elapsed time
between a trigger and the detection of a laser pulse. This yields a third mode of operation in which the detector is
synchronized to a laser and becomes a Two-dimensional Laser Range Finder (TLRF). The forth operation mode is
dedicated to Low Noise Imaging (LNIM) for the SWIR band, where the IR radiation signal is low. It can be used in both
passive or active imaging. We review some of the predicted and measured results for the different modes of operation,
both at the detector level and at the system level.
Over the last decade, SCD has developed and manufactured high quality InSb Focal Plane Arrays (FPAs), which are
currently used in many applications worldwide. SCD's production line includes many different types of InSb FPA with
formats of 320x256, 480x384 and 640x512 elements and with pitch sizes in the range of 15 to 30 μm. All these FPAs
are available in various packaging configurations, including fully integrated Detector-Dewar-Cooler Assemblies
(DDCA) with either closed-cycle Sterling or open-loop Joule-Thomson coolers.
With an increasing need for higher resolution, SCD has recently developed a new large format 2-D InSb detector with
1280x1024 elements and a pixel size of 15μm. The InSb 15μm pixel technology has already been proven at SCD with
the "Pelican" detector (640x512 elements), which was introduced at the Orlando conference in 2006.
A new signal processor was developed at SCD for use in this mega-pixel detector. This Readout Integrated Circuit
(ROIC) is designed for, and manufactured with, 0.18 μm CMOS technology. The migration from 0.5 to 0.18 μm CMOS
technology supports SCD's roadmap for the reduction of pixel size and power consumption and is in line with the
increasing demand for improved performance and on-chip functionality. Consequently, the new ROIC maintains the
same level of performance and functionality with a 15 μm pitch, as exists in our 20 μm-pitch ROICs based on 0.5μm
CMOS technology. Similar to Sebastian (SCD ROIC with A/D on chip), this signal processor also includes A/D
converters on the chip and demonstrates the same level of performance, but with reduced power consumption. The pixel
readout rate has been increased up to 160 MHz in order to support a high frame rate, resulting in 120 Hz operation with
a window of 1024×1024 elements at ~130 mW. These A/D converters on chip save the need for using 16 A/D channels
on board (in the case of an analog ROIC) which would operate at 10 MHz and consume about 8Watts
A Dewar has been designed with a stiffened detector support to withstand harsh environmental conditions with a
minimal contribution to the heat load of the detector. The combination of the 0.18μm-based low power CMOS
technology for the ROIC and the stiffening of the detector support within the Dewar has enabled the use of the Ricor
K508 cryo-cooler (0.5 W). This has created a high-resolution detector in a very compact package.
In this paper we present the basic concept of the new detector. We will describe its construction and will present
electrical and radiometric characterization results.