HgCdTe detectors and FPAs for remote sensing applications

Abstract

Short wavelength, middle wavelength, mid-long wavelength, long wavelength, and very long wavelength focal plane arrays (FPAs) are required for remote sensing applications. Advances in the Molecular Beam Epitaxy (MBE) growth of Mercury Cadmium Telluride (HgCdTe) and detector architectures utilized, have resulted in high performance detectors being fabricated in the 1 micrometers to 16 micrometers spectral range Custom Read Out Integrated Circuits (ROICs) are designed and fabricated to interface the HgCdTe detector arrays. The hybrid focal pane array is made up of the HgCdTe detector array and the CMOS-based ROIC. Hybrid FPAs performance parameters are presented. The HgCdTe detector material is used are grown by MBE on lattice matched CdZnTe substrates. Custom ROICs are fabricated in a commercial CMOS foundry. FPA D* performance values have been obtained for a multitude of spectral ranges and configurations that include; (i) (lambda) <SUB>c</SUB> equals 1.8 micrometers , 12 X 256 arrays operating at 295 K with median D* approximately 1.4 X 10<SUP>12</SUP> cm Hz<SUP>1/2</SUP>/W, (ii) (lambda) <SUB>c</SUB> equals 10.5 micrometers , 256 X 256 arrays operating at 85 K with medina D* equals 3.9 X 10<SUP>11</SUP> cm Hz<SUP>1/2</SUP>/W at a background flux (phi) <SUB>b</SUB> equals 7.82 X 10<SUP>15</SUP> ph/cm<SUP>2</SUP>-2 and (iii) (lambda) <SUB>c</SUB> equals 15.8 micrometers at 65K, 128 X 128 array operating at 40K with peak D* of 2.76 X 10<SUP>11</SUP> cm Hz<SUP>1/2</SUP>/W at a background flux (phi) <SUB>b</SUB> equals 8.0 X 10<SUP>15</SUP> ph/cm<SUP>2</SUP>- s. The performance of these FPAs will be presented.