Research & Teaching Faculty

KINETIC-STUDY OF THE EFFECTS OF H, O, N, S, NO, NO2 AND O-2 ON THE SURFACE-STATES OF INGAAS AND GAAS

TitleKINETIC-STUDY OF THE EFFECTS OF H, O, N, S, NO, NO2 AND O-2 ON THE SURFACE-STATES OF INGAAS AND GAAS
Publication TypeJournal Article
Year of Publication1995
AuthorsGu, G, Li, HJ, Ogryzlo, E
JournalJournal of the Chemical Society-Faraday Transactions
Volume91
Pagination3021-3026
Date PublishedSep
Type of ArticleArticle
ISBN Number0956-5000
KeywordsHYDROGEN PLASMA PASSIVATION, INP, intensity, PHOTOLUMINESCENCE, REAL-TIME
Abstract

The photoluminescence intensities (PLIs) from 300 nm layers of In0.53Ga0.47As and GaAs have been used to monitor carrier lifetimes, in situ, during exposure of their surfaces to a number of gaseous species at 25 degrees C. PLIs have been observed to increase by a factor of 30-50 following a few seconds exposure to atomic hydrogen at gas-phase atom densities of ca. 10(13) cm(-3). For both semiconductors the PLI was found to be ca. 40% lower while the surface was being exposed to these atoms. Additional exposure of the InGaAs to H atoms was found to reduce the PLI from this maximum by a factor of 2-3. Both the InGaAs and GaAs surfaces that had been passivated by hydrogen atoms could be de-passivated in less than a second by exposure to O, N, NO or NO2 at comparable gas-phase densities or, at a much slower rate, by exposure to O-2. The surfaces thus formed could be re-passivated by exposure to atomic hydrogen, but in the case of oxidizing species, the original behaviour of the InGaAs surface could only be restored with an HF wash. X-Ray photoelectron (XP) spectra of the surfaces under all these conditions were found to be indistinguishable. Exposure of the surface to S atoms was found to improve the passivation level of an HCl-washed surface by almost four orders of magnitude.

URL<Go to ISI>://A1995RW34100009