In:
Applied Physics Letters, AIP Publishing, Vol. 54, No. 26 ( 1989-06-26), p. 2695-2697
Abstract:
GaAs films were grown on Si substrates by a two-step method in which a thin buffer layer was first deposited using a modulated molecular beam epitaxy (MBE) technique followed by a thick layer grown by conventional molecular beam epitaxy. The film quality was evaluated using 77 K photoluminescence (PL) and double-crystal x-ray rocking curves. It was found that GaAs films grown in this way have a superior crystalline quality compared to the films prepared by normal two-step MBE. To investigate the nucleation of this buffer layer, thin GaAs layers (150 Å) were grown on Si substrates and examined by plan-view and cross-sectional transmission electron microscope. A thin, two-dimensional nucleation pattern was found in this sample, in clear contrast to the three-dimensional nucleation islands found in samples grown by conventional MBE. This showed conclusively that modulated beam molecular beam epitaxy resulted in a more uniform and two-dimensional nucleation during the initial stage of the growth as speculated earlier and is believed to be the reason for the improvement of the crystalline quality of the overgrown layer.
Type of Medium:
Online Resource
ISSN:
0003-6951
,
1077-3118
Language:
English
Publisher:
AIP Publishing
Publication Date:
1989
detail.hit.zdb_id:
211245-0
detail.hit.zdb_id:
1469436-0
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