Two-color quantum well infrared photodetector focal plane arrays

Abstract

QmagiQ LLC, has recently completed building and testing high operability two-color Quantum Well Infrared Photodetector (QWIP) focal plane arrays (FPAs). The 320 x 256 format dual-band FPAs feature 40-micron pixels of spatially registered QWIP detectors based on III-V materials. The vertically stacked detectors in this specific midwave/longwave (MW/LW) design are tuned to absorb in the respective 4-5 and 8-9 micron spectral ranges. The ISC0006 Readout Integrated Circuit (ROIC) developed by FLIR Systems Inc. and used in these FPAs features direct injection (DI) input circuitry for high charge storage with each unit cell containing dual integration capacitors, allowing simultaneous scene sampling and readout for the two distinct wavelength bands. Initial FPAs feature pixel operabilities better than 99%. Focal plane array test results and sample images will be presented.

High performance two-color one megapixel CMOS ROIC for QWIP detectors

“…An optional reference output for each color can be turned on through the serial control register. VOUTREFA [1,2] and VOUTREFB [1,2] are the biases for the output reference pad for both colors during even and odd line times. The reference output allows common mode noise introduced through the channel and output circuitry of the ROIC to be subtracted out at the system level at the expense of increased ROIC power and increased ROIC noise.…”

“…Additionally, the two-color, or dual-band, capability of FLIR's ISC0006 40 lm 320 Â 256 format array is also integrated into the latest ROIC. Separate adjustments through the signal path, including detector bias and integration time for each color, allow for maximum detector flexibility and enable individual FPAs to be optimized for various applications [2]. The format of the ISC0501 has been increased from past ROICs to 1024 Â 1024, or one megapixel, with a 30 lm pitch.…”

Absolute temperature measurements using a two-color QWIP focal plane array

“…The full width at half maximum is about 1 μm in the LW and 0.7 μm in the MW. The details of the Qwip focal plane array and the ROIC have been presented previously [7] . The camera operates at a temperature of about 68K.…”

“…QmagiQ has developed a dual-band Qwip staring focal plane array producing two simultaneous and coincident images in two different infrared spectral bands centered at wavelengths of about 4.6 μm and 8.5 μm, respectively [7] . This focal plane array constitutes a natural tool to be used as a two-color temperatureimaging device.…”

Optimization of readout circuit with background suppression for dual-band quantum well infrared focal plane array photodetector

“…The dual-band infrared readout structure circuit often does use SFD (Source Follower Detector) [3][4], DI (Direct injection) [5][6][7][8] and CTIA (capacitive-feedback Transimpedance amplifier) [9][10] on unit pixel ,recently. These integration methods are used on delay time, sense current dynamic range over more than 50dB.…”