| Autor: |
Moumanis, Kh., Ding, X., Dubowski, J. J., Frost, E. H. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 8/1/2006, Vol. 100 Issue 3, p034702, 5p, 3 Charts, 3 Graphs |
| Abstrakt: |
We report on aging and detergent washing effects in GaAs wafers passivated with hexadecanethiol (HDT) [HS(CH2)15CH3]. The evolution of the photoluminescence (PL) signal from GaAs was measured at room temperature as a function of time, up to 1000 h, for thiolated (001) GaAs that was solvent cleaned and etched using standard procedures, and for thiolated (110) GaAs that was obtained by cleaving in air. For 2 h of thiolation time, the decay of the PL signal from (001) GaAs and (110) GaAs could be fitted, respectively, with double and single exponential functions. This indicates that at least two different types of non-adiative recombination centers (NRRC) form on the (001) surface. The overall density of surface states formed on (110) GaAs is significantly lower than those on (001) GaAs. A single exponential decay of the PL signal has been observed for 18 h thiolated samples. The strong increase of the PL signal after detergent washing of (001) GaAs suggests that this treatment is effective in removal of some of the NRRC. The 19-fold enhancement of the PL signal, in comparison to that of the oxidized sample, has been obtained using the sample that, following the etching and detergent washing procedures, was thiolated with HDT. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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