Thermal Annealing Studies of Boron-Implanted HgCdTe by Electrolyte Electroreflectance

The thermal annealing properties of B⁺ implantation in HgCdTe are investigated by the electrolyte electroreflectance technique. The various thermal annealing conditions, such as temperature, time, and presence or absence of ZnS encapsulated passivation, are used as parameters to study the surface properties of HgCdTe and are characterized by electrolyte electroreflectance spectroscopy. We found that Hg accumulates near the surface region of an encapsulated sample, and Hg is lost at a depth of 1600 Å. The quality of the crystal is much improved when the sample is annealed at 200°C for a duration of over 30 minutes.