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Detector characteristics of Cu- and Au-doped High Density Vertically Integrated Photodiode (HDVIP) detectors as well as Cu-doped HDVIP Focal Plane Arrays (FPAs) are presented in this paper. Individual photodiodes in test bars were examined by measuring I-V curves and the associated resistance-area (RA) product as a function of temperature. The Au-doped MWIR [λc(78 K) = 5 μm] HDVIP detectors RoA performance was within a factor of two or three of theoretical. Noise as a function of frequency has been measured on Au-doped MWIR HgCdTe HDVIP diodes at several temperatures under dark and illuminated conditions. Low-frequency noise performance of the Au-doped MWIR diode in the various environments is characterized by the ratio α of the noise current spectral density at 1 Hz to the value of the diode current. For photocurrent at 140 K, αPHOTO = 1.8 x 10-5. The value of αPHOTO is the same at both zero bias and 100 mV reverse bias. At 160 K, αPHOTO is slightly lower but still in the low 10-5 range. Excess low-frequency noise measured at 140 K and 100 mV reverse bias in the dark has αDARK = 1.4 x 10-5. At 160 K and 100 mV reverse bias, αDARK is in the mid 10-5 range. At 140 K,the dark current at 8.2 V reverse bias was equal to the photocurrent at 100 mV reverse bias and close to the photocurrent at zero bias. αDARK = 1.85 x 10-3 at -8.2 V. This ratio is two orders of magnitude greater than αPHOTO. At 8.2 V reverse bias, the current was amplified by avalanche processes. Similar results were obtained on the Au-doped diode at 160 K. Diffusion current dominates dark current at 100 mV reverse bias at T = 185 K and T = 220 K. The ratio, αDARK approximately αPHOTO in the low to mid 10-5 range, i.e. dark diffusion current generates excess low frequency noise in the same manner as photocurrent. In addition, 256 x 256 Cu-doped detector arrays were fabricated. Initial measurements had seven out of ten FPAs having operabilities greater than 99.45% with the best 256 x 256 array having only two inoperable pixels.
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