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Significant progress has been achieved in technology of the InGaAs focal plane arrays (FPA) detector operating in short
wave infrared (SWIR) last two decades. The no cryogenic cooling, low manufacturing cost, low power, high sensitivity
and maneuverability features inherent of InGaAs FPA make it as a mainstream SWIR FPA in a variety of critical military,
national security, aerospace, telecommunications and industrial applications. These various types of passive image
sensing or active illumination image detecting systems included
range-gated imaging, 3-Dimensional Ladar, covert
surveillance, pulsed laser beam profiling, machine vision, semiconductor inspection, free space optical communications
beam tracker, hyperspectroscopy imaging and many others. In this paper the status and perspectives of hybrid InGaAs
FPA which is composed of detector array (PDA) and CMOS readout integrate circuit (ROIC) are reviewed briefly. For
various low light levels applications such as starlight or night sky illumination, we have made use of the interface circuit
of capacitive feedback transimpedance amplifier (CTIA) in which the integration capacitor was adjustable, therefore
implements of the physical and electrical characteristics matches between detector arrays and readout intergrate circuit
was achieved excellently. Taking into account the influences of InGaAs detector arrays' optoelectronic characteristics on
performance of the FPA, we discussed the key parameters of the photodiode in detailed, and the tradeoff between the
responsivity, dark current, impedance at zero bias and junction capacitance of photosensitive element has been made to
root out the impact factors. As a result of the educed approach of the photodiode's characteristics optimizing which
involve with InGaAs PDA design and process, a high performance InGaAs FPA of 30um pixel pitch and 320×256 format
has been developed of which the response spectrum range over 0.9um to 1.7um, the mean peak detectivity (λ=1.55μm)
was 6×1012 cmHz1/2W-1 and dynamics range reached 68 dB at room temperature. Making use of the fabricated 320×256
InGaAs FPA, the concerning objects can be imaged in the low light level or nightglow background.
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