Direct measurement of the potential spike energy in AlGaAs/GaAs single-heterojunction bipolar transistors

Author

Lin, H.H. ; Lee, S.C.

Author_Institution

National Taiwan University, Taipei, Taiwan, Republic of China

Volume

6

Issue

8

fYear

1985

fDate

8/1/1985 12:00:00 AM

Firstpage

431

Lastpage

433

Abstract

A balanced two-step current transport theory, i.e., thermionic emission followed by Shockley diffusion, is applied to study the emitter-base (EB) potential spike energy in the AlGaAs/GaAs single-heterojunction bipolar transistor. It is found, surprisingly, that when the transistor is operated in the active region the $I-V$ characteristics of the collector current (IC) versus base-emitter applied voltage (VBE) exhibits an ideality factor of 1.237. This non-1kT transfer characteristics is due to the bias-dependent potential spike energy at the emitter-base heterojunction. The reverse I-V characteristics of emitter current (IE) versus base-collector bias (VBC), however, shows the traditional 1kT behavior. The difference between ICand IEat the same applied voltage ( $V_{BE} = V_{BC}$ ) determines the potential spike energy (ΔE). It turns out that Δ E/q = 0.19 $(V_{BE} - 0.48)$ where $q$ is the unit charge. This indicates that the potential spike appears only when the applied voltage $V_{BE} > 0.48$ V.

Keywords

Bipolar transistors; Electrons; Energy measurement; Gallium arsenide; Helium; Heterojunction bipolar transistors; Potential energy; Substrates; Thermionic emission; Voltage;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/EDL.1985.26180

Filename

1485333