Accession Number:

ADA257931

Title:

High Resistivity GaAs Epilayers by Oxygen Doping

Descriptive Note:

Annual rept. 1 Sep 1991-31 Aug 1992

Corporate Author:

CARNEGIE-MELLON UNIV PITTSBURGH PA

Personal Author(s):

Report Date:

1992-09-30

Pagination or Media Count:

14.0

Abstract:

During the first year of research our OMVPE system has been retrofitted with a charcoal exhaust scrubber, toxic gas detector, and process gas delivery system. All components have been fully tested and calibrated for GaAs deposition. High quality undoped GaAs epilayers have been deposited with following characteristics specular morphology, low free carrier concentration p 1 Xl0 to the 15th power cm-3 and high mobility 4,000 cm2Vs at 77K. The dominant acceptor is carbon originating from gallium source as determined by the high resolution photoluminescence. Doping of GaAs epilayers with dimethylaluminum methoxide resulted in incorporation of both oxygen and aluminum in concentrations up to 5x10 to the 18th power 01 8 cm-3 and 7x10 to the 19th power 019 cm-3, respectively. Oxygen concentration increases rapidly with decreasing deposition temperature. Heavily oxygen doped layers obtained either by high DMAIMO flow or growth at temperatures below 600 deg C are highly resistive and exhibit extremely low carrier lifetime. Photoluminescence measurements detected new luminescence bands in 85G1000 nm range which are assigned to deep oxygen induced traps. GaAs, Oxygen, MOCVD, Growth, Buffer Layers.

Subject Categories:

  • Organic Chemistry
  • Physical Chemistry
  • Chemical, Biological and Radiological Warfare
  • Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE