High performance Be+implanted InSb photodiodes

A new Be⁺ion implantation process for InSb photodiode fabrication has been developed, and performance levels comparable or superior to those obtained with standard diffused structures have been demonstrated. In addition to the implantation technique, an SiO2surface passivation is being developed to replace the former anodization process. The SiO2has demonstrated improved stability and repeatability, as well as surface state densities in the range of 10¹¹cm^-2eV^-1, and resistivities of -cm at 300K. Data on many diodes show zero bias resistance-area products (RoA) of -cm²at 77K and over -cm²at 30K, which are the highest known values reported for such devices. Quantum efficiences near 80 percent at 77K and a wavelength of 5.4 µm, have also been measured. Data on high density (> 1000 elements) arrays indicate good uniformity of operation, with the standard deviation in RoA showing a 50 percent improvement over values obtained for Cd diffused structures.