In this paper, we describe a 16 × 64 InSb CID 2-D array using a concentric gate structure and planar processing designed for scanning TDI applications. An in-depth analysis of the physical mechanisms of the charge-injection device and a simplified dual-gate CID readout modeling based on a piecewise linear approximation are discussed. Excellent array performance was measured using the sequential-row-inject (SRI) readout scheme in its simplest form. Good dual-gate coupling and charge transfer demonstrate the feasibility of the ideal mode operation. The empirical results are also in agreement with the calculations predicted by the readout modeling and analysis using the material and device parameters.

Characteristics and readout of an InSb CID two-dimensional scanning TDI array

This paper reviews Indium Antimonide Charge Injection Device (CID) Technology. These detectors consist of MIS capacitors formed on InSb wafers using integrated circuit-like processing. When biased into depletions, the capacitors form integrating detectors for use in the 3-5 μ band. Single capacitors are used to form line array sites while two coupled capacitors form sites of area arrays. Silicon scanning chips are used to address the sites and implement the readout of the signal charge. Advances in the technology permit the design of IR focal planes with large numbers of detectors. General Electric has developed line arrays with up to 512 elements and staring arrays with up to 128 x 128 elements. This paper first reviews the basic CID mechanisms and briefly describes array fabrication. This is followed by a description of InSb line arrays along with their readouts and performance. Two dimensional arrays and their readouts are presented including the 128 x 128 staring array.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Status Of CID InSb Detector Technology

New information concerning the readout of charge-injection device (CID) arrays, used for optical detection, is obtained from the well known Kirchhoff voltage equation for surface potential. Emphasis is placed on those readout modes involving read on injection which have been found useful with infrared-sensitive CID's. The theory obtained relates surface potential, depletion depth, mobile charge in the inversion well, and voltage on the floating gate before, during, and after injection. Previous work which obtained some properties of individual gates with filled or empty inversion wells is extended to pairs of coupled gates and partially filled potential wells. Coupled gates operating in ideal mode and in charge-sharing mode, with either column injection or row injection are included. Additional properties derived are high-frequency differential capacitance, output voltage, readout efficiency and its differential analog, transient response, charge-sharing efficiency, and differential charge-sharing efficiency. Numerical computations are given for representative CID pixels on InSb.

Output properties of charge-injection devices: Part I&#8212;Read on injection

Unlike Si or HgCdTe CID (charge injection device) arrays, which normally operate at ∼1 MHz with the presence of a ≲ 10 percent fat zero (i.e., ideal mode), current InSb CID arrays fabricated on InSb substrates can operate either at a much lower clock frequency of ∼ 10 kHz (i.e., slow charge transfer mode), or when both row and column potential wells are partially filled with a large bias charge (i.e., charge sharing mode). The slow charge transfer mode is very ineffective in reading out signal charge from a large-area array and the charge sharing mode exhibits difficulties such as reduced readout efficiency, increased line capacitance, and a large photocurrent effect. By contrast, the ideal mode is free of these problems. In this paper we describe the design and fabrication of an InSb CID array, which for the first time, successfully demonstrates the ideal mode operation.

Ideal mode operation of an InSb charge injection device

Two evolutionary infrared remote sensing experiments provide the basis for the development of an operational mapping capability for geology exploration. A 10-band radiometer scheduled for an early Shuttle flight has completed an aircraft flight program which demonstrated the utility of a number of narrow spectral channels. A multispectral mapper utilizing an infrared area array detector to acquire simultaneous images in multiple wavelengths is being assembled. A design concept for an operational sensor which employs area arrays for registered multispectral image data acquisition is under study. The sensor would utilize onboard spectral band selection, radiometric correction, and data compression to satisfy the demanding requirements of the user community.

Experiments in infrared multispectral mapping of earth resources

This paper describes the factors governing the Performance Efficiency (PE) of Indium Antimonide Charge Injection Devices (CID) arrays. Factors influencing PE in both line and area arrays are considered and compared to experimental results. An important factor re-lates to the signal charge loss of a dual gate array operating in the charge sharing mode (CSM). The chief advantages of the CSM are that it overcomes charge transfer problems that might be present in practical arrays, and it is believed to be radiation damage resistant. The chief limitation is that only the charge residing under the sensing gate of the dual gate site is read out. This loss can be lessened by designing the sensing gate to be a large fraction of the total storage area. Performance data of lx32, lx64 line arrays, 24x16 and 32x32 dual gate area arrays are presented. Line arrays FE up to 56 percent, responsivity variation below 10 percent, and D* of about 3x1011 cm HZ½/watt have been measured.© (1979) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Performance Efficiency Of InSb Charge Injection Devices (CID)

This paper reviews the status of two Indium Antimonide Charge Injection Device (CID) focal planes, one composed of multiple line arrays, the other made with an area array using random access addressing. After an introduction to CID operation, factors governing Performance Efficiency (PE) in both line and area arrays are considered and compared to experimental results. The charge sharing mode of operation of a two dimensional array is presented, along with its perform-ance implications. The linear focal plane consists of 48 linear arrays, each with 64 elements. Each InSb array is addressed by a silicon scanner chip. The scanner outputs are serviced by preamp chips mounted perpendicular to the focal plane. The 32x32 element area arrays have been coupled to combinatorial decoders permitting random selection of any site of the array. Focal planes consisting of a single 32x32 array with two silicon decoders mounted in sealed off glass dewars are described.© (1980) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

R. W. Aldrich

Papers

Performance Efficiency Of InSb Charge Injection Devices (CID)

Advances in InSb Charge Injection Device (CID) Focal Planes