Reliability issues in SiGe HBTs fabricated on CMOS-compatible thin-film SOI

A comprehensive investigation of reliability issues in both fully-depleted and partially-depleted SiGe HBTs-on-SOI is presented. The devices were subjected to "mixed-mode" stress at 300 K and at 77 K, and we have analyzed the changes in base current IB, collector resistance Rc, M-1, and AC performance. A comparison of mixed-mode stress to conventional reverse EB bias stress is also made, and significant differences are observed. The thermal resistance Rth of the devices is extracted over the 50 K - 300 K range. © 2006 IEEE.