Abstract
In this paper, a transient voltage suppressor using a diode-activated SiGe heterojunction bipolar transistor (HBT) is proposed. The capacitance, DC current-voltage (I-V) characteristics, and transmission line pulse (TLP) I-V characteristics of this combination device are investigated. An optimization guideline of the combination device is presented, verified by the corresponding simulation results, and a simple and effective method for achieving the target breakdown voltage is demonstrated. By combining the diode and SiGe HBT, the new structure exhibits both a low capacitance and a low breakdown voltage for protection against electrostatic discharge and electrical overstress in discrete or on-chip applications. © 2009 The Japan Society of Applied Physics.