Abstract: | GaAs-based heterojunction bipolar transistors (HBTs) are of interest for a wide variety of applications. However, concerns about the long-term stability of the device have recently arisen. This paper describes the physics of HBT degradation under bias stress as similar to GaAs light-emitting diode (LED) and laser diode (LD) degradation. TEM, electroluminescence, and electrical measurements support this model. Additionally, the model also indicates the factors in epitaxial growth and device processing that are critical to device reliability. |