Abstract: A resonant, photoconductive detector for infrared radiation in which a reduced-volume pattern of the photoconductor permits impedance-matching to free space. The photoconductor pattern is a split-ring pattern, typically made of HgCdTe, which is virtually cylindrically symmetric, yielding a non-polarization-sensitive response. The region below the patterned photoconductor is a quarter-wavelength resonant cavity type structure. The ohmic contacts are conductively distanced from one another by use of the split-ring pattern. Spacing dimensions are slightly less than a wavelength for the infrared wavelengths to be absorbed; but ring-width dimensions of the photoconductor are substantially less to effect the volume reduction and the corresponding detectivity and radiation-hardness improvements. The essentially cylindrical isotropic pattern eases fabrication by averaging etching nonuniformities.

Abstract: An infrared detector, having improved infrared absorptance and operating performance at or near ambient as well as the cryogenic temperature ranges. The infrared detector, in one embodiment includes a multi-filament HgCdTe detector region mounted upon a CdTe substrate, a metallic reflective region placed in front of, or behind, the HgCdTe detection region forming a resonant layer between the reflective region and HgCdTe. Electrical contacts operable to detect the change in resistance of the HgCdTe detector filaments are connected to the detector region. Embodiment for a back surface illuminated detector device is described for use in the 8 micron to 12 micron, longwave infrared (LWIR) range. Improved operation in the LWIR range at higher temperatures results in detector arrays having decreased cooling needs and infrared detector systems produced with a significant decrease in overall system weight.

Abstract: A process for fabricating a front surface resonant mesh array detector produces a detector of reduced size. The reduced size results in enhanced responsivity, and minimizes thermal stress between the detector and typical array substrates, enabling fabrication of arrays using front surface resonant mesh array detectors.

Abstract: A method of forming a eutectic bond, of Cadmium Telluride to Sapphire utilizing the Gold/Silicon eutectic bonding of the Cadmium Telluride to the Sapphire. A multi-layer structure of: Chromium which provides adhesion to the Cadmium Telluride; a Titanium layer which functions as a diffusion barrier to the Gold, and a Gold layer are sequentially evaporated on the Cadmium Telluride; a separate multilayered structure of: Silicon grown on Sapphire, and Gold evaporated upon the Silicon. These two multilayered structures are then eutectically bonded. This method enables the expansion coefficient of the eutectic layer to be tailored through the Gold concentration to match that of the Cadmium Telluride. This method also allows the bonding stress to be confined between the Gold/Silicon eutectic and the Sapphire substrate, eliminating the bonding stress in the Cadmium Telluride. Also, due to the precision of the thickness of the evaporated layers, the bonded substrates are inherently planar and parallel.