A survey of heterojunction bipolar transistor (HBT) device reliability

Heterojunction bipolar transistor (HBT) technology has become a major player in wireless communication, power amplifier, mixer, and frequency synthesizer applications. HBTs extend the advantages of silicon bipolar transistors to significantly higher frequencies. Since the mid-1980s, HBT technology development has focussed on reducing cost and improving reliability which, in turn, led to numerous commercial products, such as prescalers, gate arrays, digital-to-analog converters, mux/demux chip sets, logarithmic amplifiers, RF chip sets for CDMA wireless communication systems, and power amplifiers for cellular communications. They have become a natural choice for very high frequency military applications requiring a high current drive, high transconductance, high voltage handling capability, low noise oscillator, and uniform threshold voltage. Emerging HBT technologies allow the integration of a large quantity of high performance RF circuits and high speed digital circuits on a single chip. This paper provides an overview of HBT device reliability issues.