The d.c. characteristics of InGaAs/InP single heterojunction bipolar transistors (SHBTs) were studied for the first time under high energy (approximately 1 MeV) electron radiation of cumulative dose up to 5.4×1015 electrons/cm2. No degradation was observed for electron doses below 1015/cm2. For electron doses greater than 1015/cm2 the following degradation effects were observed: (1) decrease in collector current; (2) decrease in current gain up to 50%; (3) an increase in collector saturation voltage by 0.2-0.8 V depending on base current; and (4) increase in output conductance. The degradation of collector current and current gain are thought to be due to increased recombination caused by radiation-induced defects in the base-emitter junction. The increase in collector saturation voltage is attributed to an increase in emitter contact resistance after irradiation. The increase in the avalanche multiplication in the reverse biased base-collector junction caused by radiation induced defects is believed to be responsible for increased output conductance after irradiation.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Safety, Risk, Reliability and Quality
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Electrical and Electronic Engineering