HETEROEPITAXIAL STRUCTURES WITH HIGH TEMPERATURE STABLE SUBSTRATE INTERFACE MATERIAL

摘要

Crystalline heterostructures including an elevated crystalline structure extending from one or more trenches in a trench layer disposed over a crystalline substrate are described. In some embodiments, an interfacial layer is disposed over a silicon substrate surface. The interfacial layer facilitates growth of the elevated structure from a bottom of the trench at growth temperatures that may otherwise degrade the substrate surface and induce more defects in the elevated structure. The trench layer may be disposed over the interfacial layer with a trench bottom exposing a portion of the interfacial layer. Arbitrarily large merged crystal structures having low defect density surfaces may be overgrown from the trenches. Devices, such as III-N transistors, may be further formed on the raised crystalline structures while silicon-based devices (e.g., transistors) may be formed in other regions of the silicon substrate.