Details

Autor(en) / Beteiligte

• EYINK, K. G
• CAPANO, M. A
• WALCK, S. D
• HAAS, T. W
• STREETMAN, B. G

Titel

A comparison of the critical thickness for MBE grown LT-GaAs determined by in-situ ellipsometry and transmission electron microscopy

Ist Teil von

• Journal of electronic materials, 1997-04, Vol.26 (4), p.391-396

Ort / Verlag

New York, NY: Institute of Electrical and Electronics Engineers

Erscheinungsjahr

1997

Quelle

SpringerLink

Beschreibungen/Notizen

• The growth of low temperature (LT) GaAs by molecular beam epitaxy has been studied using ellipsometry. Different regimes of growth were observed in the data, depending on film thickness. Epitaxial growth of pseudomorphic LT-GaAs occurred immediately above the substrate, followed by a layer with changing dielectric properties. This upper layer can be modeled as a two-phase region consisting of epitaxial LT-GaAs and small grained, polycrystalline GaAs, which increases in volume fraction with increasing layer thickness. For sufficiently thick LT layers, cross-sectional transmission electron microscopy analysis showed pyramidal defects that were composed primarily of highly twinned regions. The ellipsometry data showed a deviation from the homogeneous growth model at a thickness less than the thickness at which the pyramidal defects nucleated in all samples.