The alloy temperature dependence of Voffset and Rcontact is studied, and an optimal alloy temperature range for the best trade-off between Voffset and Rcontact, is given for thin base HBTs. In addition,the reason for the high Voffset at high alloy temperature is interpreted using Schottky clamped theory. The lower Voffset of our U-shaped emitter HBT than that of traditional strip emitter HBTs is explained.
