Influencing the Bow of Thick Hydride Vapor Phase Epitaxial GaN by Prestraining MOVPE Templates
نویسنده
چکیده
A major challenge that arises when growing GaN substrates in a single run process is the remaining curvature of the freestanding material after the removal of the foreign substrate. For a long time the dislocation density gradient has been suspected to be the cause. However, by conducting etching experiments, we have found that this cannot be the only reason. We postulate that the initial strain situation of the MOVPE template can have a big influence on the bowing of HVPE samples and on the remaining curvature of separated GaN layers. By investigating accordingly grown samples, we present proof of this assumption.
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