High electric field induced degradation of the DC characteristics in Si/SiGe HEMT's

We report, for the first time, results on the reliability of Si/SiGe HEMT´s. The present work addresses the high electric field stress effects on the DC characteristics. In particular, we report the variations of the output characteristics (drain and gate current), of the transconductance, of the threshold voltage, and of the breakdown voltage. Subsequently, possible degradation mechanisms are presented. The observed variations are discussed in comparison with similar experiments carried out on PHEMT´s issued of the III-V technology. Keywords: HEMT´s, Reliability, SiGe, DC Characteristics