Hydrogen plasma removal of AlGaAs oxides before molecular beam epitaxy

Kent D. Choquette, M. Hong, S. N.G. Chu, H. S. Luftman, J. P. Mannaerts, R. C. Wetzel, R. S. Freund

Research output: Contribution to journalArticlepeer-review


We report a method for the removal of AlxGa1-xAs native oxides for 0≤x≤1, prior to molecular beam epitaxial overgrowth. The oxides formed on epilayers of AlGaAs after atmospheric exposure are removed in an electron cyclotron resonance hydrogen plasma with a substrate temperature less than 400°C. Reflection high energy electron diffraction indicates the plasma-prepared AlGaAs surface are oxide-free and crystalline; after a vacuum anneal to 250-500°C, GaAs or AlGaAs are epitaxially overgrown on these surfaces. Secondary ion mass spectroscopy detects C, O, and Si impurities at the interfaces, where their concentrations increase with increasing Al content of the exposed surface. The quality of the interface and the overgrown film, as observed by transmission electron microscopy, are found to be better for lower interface impurity densities.

Original languageEnglish (US)
Pages (from-to)735-737
Number of pages3
JournalApplied Physics Letters
Issue number7
StatePublished - 1993
Externally publishedYes

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)


Dive into the research topics of 'Hydrogen plasma removal of AlGaAs oxides before molecular beam epitaxy'. Together they form a unique fingerprint.

Cite this