Photoreflectance characterization of graded emitter InAlGaAs/InGaAs HBTs

Author

Wojtowicz, Mike ; Block, T. ; Pascua, D. ; Han, A.C. ; Streit, D.

Author_Institution

Electron. & Technol. Div., TRW Inc., Redondo Beach, CA, USA

fYear

1996

fDate

21-25 Apr 1996

Firstpage

576

Lastpage

577

Abstract

We have measured the photoreflectance spectra from the emitter region of In_0.53(Al_xGa_1-x)_0.47As (0.3<x<1.0) graded emitter InGaAs/InAlGaAs HBTs grown by MBE on InP substrates. From the Franz-Keldysh oscillations we have determined the built-in dc electric fields and energy gaps which were then compared to modeled results. Features were identified corresponding to the uniform InAlAs layer as well as the graded layer and good agreement between the modeled and experimental results was obtained. A feature originating in the graded emitter region has been identified and correlated to base dopant diffusion into the emitter

Keywords

III-V semiconductors; aluminium compounds; energy gap; gallium arsenide; heterojunction bipolar transistors; indium compounds; photoreflectance; reflectivity; Franz-Keldysh oscillations; InAlGaAs-InGaAs; InP substrate; MBE; base dopant diffusion; built-in DC electric field; energy gap; graded emitter InAlGaAs/InGaAs HBT; photoreflectance spectra; Electrostatics; Heterojunction bipolar transistors; Indium compounds; Indium gallium arsenide; Indium phosphide; Molecular beam epitaxial growth; Monitoring; Photonic band gap; Semiconductor process modeling; Substrates;

fLanguage

English

Publisher

ieee

Conference_Titel

Indium Phosphide and Related Materials, 1996. IPRM '96., Eighth International Conference on

Conference_Location

Schwabisch-Gmund

Print_ISBN

0-7803-3283-0

Type

conf

DOI

10.1109/ICIPRM.1996.492313

Filename

492313