Formation of shallow photodiodes by implantation of boron into mercury cadmium telluride

Abstract

Hall-effect measurements on p-type MCT implanted with 1 × 1014 B+/cm2 at 150 keV show that an abrupt junction is formed at a depth of 0.6 ± 0.12 μm after annealing at 230° for 7 min with a ZnS cap. Prior to the anneal the carrier profile was graded and extended to a depth of 5.0 ± 1.0 μm. Photodiodes have been formed by a dual implant of 5 × 1014 B+/cm2 at 100 keV and 50 keV, and after annealing a five-fold improvement in RoA has been measured to give a value of 1.2 Ωcm2.