Impact ionization in InP-based HEMTs

Author

Webster, Richard T. ; Anwar, A.F.M. ; Wu, Shangli

Author_Institution

Rome Lab., Hanscom AFB, MA, USA

fYear

1997

fDate

4-6 Aug 1997

Firstpage

172

Lastpage

181

Abstract

A physical model of impact ionization in InP HEMTs is developed and incorporated in an equivalent circuit model for comparison with experimental observations showing excellent agreement. Impact ionization is modeled by a voltage dependent current source in an RC network at the drain end. The RC branch behaves like a low pass filter that imparts a frequency dependence to the impact ionization current source and enables one to model the inductive nature of S₂₂ at low frequencies. Theoretical calculations show a compression of transconductance due to impact ionization with increasing gate bias that is supported by experimental data. Finally, an experimental method is suggested to extract impact ionization induced transconductance using Y₂₁

Keywords

III-V semiconductors; S-parameters; equivalent circuits; high electron mobility transistors; impact ionisation; indium compounds; microwave field effect transistors; millimetre wave field effect transistors; semiconductor device models; 0.4 to 40 GHz; InP; InP-based HEMTs; RC network; equivalent circuit model; frequency dependence; gate bias; impact ionization; physical model; transconductance compression; voltage dependent current source; Indium compounds;

fLanguage

English

Publisher

ieee

Conference_Titel

High Speed Semiconductor Devices and Circuits, 1997. Proceedings., 1997 IEEE/Cornell Conference on Advanced Concepts in

Conference_Location

Ithaca, NY

ISSN

1079-4700

Print_ISBN

0-7803-3970-3

Type

conf

DOI

10.1109/CORNEL.1997.649356

Filename

649356