Effect of implant temperature on electrical characteristics of implanted monocrystalline-emitter bipolar transistors

Strong effect on the gain of implanted monocrystalline emitter transistor was seen due to a disk temperature increase caused by reduced cooling. Observed changes were quite significant, causing product out of tolerance condition at temperatures below the ones normally causing resist blistering. The mechanism for the observed phenomena is proposed, based upon reduced TED and change in amorphization dose at elevated temperature. SIMS profiles of As
⁺
after implant and anneal are provided. The importance of precise temperature control for a narrow base implanted monocrystalline emitter bipolar transistor is highlighted and process control techniques are proposed.