N2atmosphere annealing effect on HgCdTe electrical damage induced by ICP etching process

Abstract

N 2 atmosphere annealing process to recover ICP etching induced damage on p type mercury vacancy HgCdTe film has been exploited in this paper. ICP etching and N 2 atmosphere annealing processes were carried out on a series of Hgvacancy-doping p-type HgCdTe samples. The carrier transport and lifetime properties of these samples were characterized by Hall measurement and microwave reflectance method respectively. P-to-n electrical damage of the surface HgCdTe film induced by the ICP etching process was deduced from the polarity inversion of Hall coefficient. The carrier transport and lifetime properties were similar to those of the non-etched samples, indicating that the surface HgCdTe electrical damage was recovered partially by annealing at 210°C for 2 hours. I-V and R-V characteristics curves of photodiodes fabricated on the etched and N 2 atmosphere annealing processed MCT samples were also comparable to those of photodiodes on the non-etched MCT samples in the following experiments. These results show that N 2 atmosphere annealing process is a readily available and promising recovering technique for HgCdTe ICP etching induced damage.