Compound semiconductor wafer with defects propagating prevention means
AssigneeSumitomo Electric Industries, Ltd.
InventorsTakashi Iwasaki, Naoyuki Yamabayashi, Yoshiki Miura
Life of this patent
Estimating the term…
Abstract
A compound semiconductor epitaxial wafer has a heteroepitaxial crystal layer grown on a compound semiconductor crystal substrate which has a substantially circular configuration and is free of dislocation defects at least in a central area surrounded by a cut-off that prevents defects from propagating radially inwardly into said central area.
Claims15
A compound semiconductor epitaxial wafer, comprising a compound semiconductor single crystal substrate having a substantially circular configuration, a heteroepitaxial crystal layer formed on said compound semiconductor single crystal substrate, means for preventing a propagation of defects, said defects propagation preventing means forming part of said wafer and extending into said substrate to surround an area of said wafer prior to wafer processing so that defects starting outside said area during wafer processing of said wafer cannot propagate into said area surrounded by said defects propagation preventing means during said processing, and wherein said compound semiconductor single crystal substrate is free of dislocation defects at least within said area surrounded by said defects propagation preventing means.
A compound semiconductor epitaxial wafer, comprising a compound semiconductor single crystal substrate, a heteroepitaxial crystal layer formed on said substrate, said substrate comprising a central area which is free of dislocation defects, said compound semiconductor wafer further comprising, as part of said wafer, means extending into said substrate for cutting off a linkage between a crystal portion in said central area of said substrate from a crystal portion outside said central area of said substrate, said cutting off means extending through said heteroepitaxial crystal layer and into said substrate prior to wafer processing, whereby said cutting off means suppresses propagation of crystal defects to said area free of dislocation defects during processing of said wafer.
Dependencies are inferred from the claim text.