Title :
Initial degradation of base-emitter junction in carbon-doped InP/InGaAs HBTs under bias and temperature stress
Author :
Kurishima, Kenji ; Yamahata, Shoji ; Nakajima, Hiroki ; Ito, Hiroshi ; Watanabe, Noriyuki
Author_Institution :
NTT Syst. Electron. Labs., Atsugi, Japan
Abstract :
Bias-temperature stress tests were performed to examine the stability of base-emitter junction characteristics of carbon-doped InP/InGaAs heterojunction biopolar transistors (HBT´s). Two different kinds of degradation modes were observed from the Gummel I-V characteristics. One is characterized by the gradual increase in a nonideal base current. The generation of the nonideal current strongly depends on the crystallographic orientation of the emitter mesa. The other degradation mode was observed when a large current (200 kA/cm/sup 2/) was injected under a high ambient temperature (180/spl deg/C). This degradation is characterized by an initial decrease in turn-on voltage and significant drop in current gain.
Keywords :
III-V semiconductors; carbon; gallium arsenide; heterojunction bipolar transistors; indium compounds; semiconductor device reliability; thermal stability; 180 C; C-doped InP/InGaAs HBT; Gummel I-V characteristics; InP-InGaAs:C; base-emitter junction; base-emitter junction characteristics; bias stress; bias-temperature stress tests; crystallographic orientation dependence; current gain reduction; degradation modes; emitter mesa; heterojunction biopolar transistors; high ambient temperature; initial degradation; junction stability; large current injection; nonideal base current; temperature stress; turn-on voltage reduction; Crystallography; Degradation; Heterojunctions; Indium gallium arsenide; Indium phosphide; Performance evaluation; Stability; Stress; Temperature; Testing;
Journal_Title :
Electron Device Letters, IEEE
