Crosshatch patterns in GaAs films on Si substrates due to thermal strain in annealing processes

NTT Electrical Communications Laboratories, Tokai, Ibaraki‐ken 319‐11, Japan
Applied Physics Letters (Impact Factor: 3.52). 01/1988; DOI: 10.1063/1.98303
Source: IEEE Xplore

ABSTRACT Crosshatch patterns were observed for the first time on the annealed GaAs film surfaces on Si substrates. The alignment of etch pits and the reduced electron beam induced current (EBIC) lines were also observed. They indicate that dislocations move and arrange themselves onto specified slip planes of {111} directions due to thermal strains in the annealing process. Flatter morphologies and more reduced EBIC intensity variations of the samples with crosshatch patterns indicate improved GaAs film quality.

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