Inline sheet charge control during MBE production of AlGaAs/InGaAs pHEMTs using AlAs etch stopper for GaAs cap removal

Author

Zhou, Guoliang ; Liu, Wayne ; Lin, M.-E.

Author_Institution

Alpha Ind. Inc., Woburn, MA, USA

fYear

2000

fDate

2000

Firstpage

37

Lastpage

41

Abstract

We report the investigation of using AlAs etch stopper for selective removal of GaAs cap in order to monitor sheet charge density during MBE production of AlGaAs/InGaAs pHEMTs. Etching selectivity/duration and Ohmic contact resistance were compared for AlAs layers with different thickness. PHEMT structures at different etching stages were characterized by Hall measurement, X-ray diffraction, and noncontact sheet resistance measurement. The stopping time for 5 to 25 Å AlAs films in ammonia hydroxide based etching solution was found to be within the range of 5 to 35 minutes. True sheet charge density confined within quantum well is routinely obtained without the interruptions of production for extra calibration growth

Keywords

III-V semiconductors; aluminium compounds; contact resistance; etching; gallium arsenide; high electron mobility transistors; indium compounds; molecular beam epitaxial growth; semiconductor growth; 5 to 25 A; AlAs; AlAs etch stopper; AlGaAs-InGaAs; AlGaAs/InGaAs pHEMTs; GaAs; GaAs cap removal; Hall measurement; MBE production; Ohmic contact resistance; X-ray diffraction; etching duration; etching selectivity; inline sheet charge control; noncontact sheet resistance; sheet charge density; stopping time; Contact resistance; Electrical resistance measurement; Etching; Gallium arsenide; Indium gallium arsenide; Molecular beam epitaxial growth; Monitoring; Ohmic contacts; PHEMTs; Production;

fLanguage

English

Publisher

ieee

Conference_Titel

Compound Semiconductors, 2000 IEEE International Symposium on

Conference_Location

Monterey, CA

Print_ISBN

0-7803-6258-6

Type

conf

DOI

10.1109/ISCS.2000.947125

Filename

947125