Patent ID: 6783592
Filing Date: 2004-08-31
Classification: C30B,H01L

Abstract:
A method for growing at least one single crystal layer on a selected single crystal substrate having an average density of replicating nonremovable stepsource dislocations, wherein said at least one single crystal layer contains at least one replicating nonremovable stepsource dislocation, confined to selected lateral point locations, said method comprising the steps of:a) choosing a single crystal substrate material which exhibits a property that the material therein contains at least one growth plane orientation whereby under selected growth conditions the growth rate due to step-flow growth along the basal plane is greater than at least one hundred (100) times a growth rate perpendicular to the basal plane due to growth involving two-dimensional nucleation; b) preparing a planar first growth surface on said single crystal substrate that is parallel to within a predetermined angle relative to a selected crystal plane of said single crystal substrate; c) removing material in said first growth surface so as to define at least one selected separated second growth surface with top surface area that is selected to be less than twice the inverse of said average density of replicating nonremovable stepsource dislocations in the said single crystal substrate and with border shape selected to have at least one enclosed hollow region, said selected separated second growth surface defining a cumulative hollow region area enclosed by at least one interior border shape selected to obtain lateral coalescence at said selected lateral point location, wherein said cumulative hollow region area is selected greater than half the inverse of the said average density of replicating nonremovable stepsource dislocations in said single crystal substrate; d) treating said at least one selected separated second growth surface so as to remove any removable sources of unwanted crystal nucleation and any removable sources of steps therein; e) depositing a homoepitaxial film on said separated second growth surface under selected conditions so as to provide a step-flow growth while suppressing two-dimensional nucleation; f) continuing said deposition of said homoepitaxial film so that said step-flow growth results and produces at least one lateral cantilevered web structure growing laterally toward the interior of said at least one enclosed hollow region; g) continuing said deposition of said homoepitaxial film until said at least one lateral cantilevered web structure completes its lateral coalescence at said selected lateral location thereby completely covering said at least one enclosed hollow region with at least one complete crystal roof forming at least one selected separated third growth surface of desired size and shape; and h) continuing said deposition of said homoepitaxial film until homoepitaxial film of desired vertical thickness on top of said selected separated third growth surface is achieved.