A comparative study of silicon nitride passivation on InP-based double heterojunction bipolar transistors (DHBTs) with different emitter structures

Abstract

The impact of emitter layer structure on the electrical characteristics of InP HBTs subjected to SiN passivation was investigated. Negligible degradation of current gain due to SiN passivation has been obtained in the InP HBTs with InAlAs emitter. The experimental results indicate that the base-emitter junction leakage current and its stability depend critically on the emitter structure. The suppression of PECVD SiN induced degradation in InP-based HBTs with InAlAs emitter could be attributed to the high resistance to plasma damage of InAlAs material.