Growth and Coalescence Studies of (112̄2) Oriented GaN on Pre-Structured Sapphire Substrates Using Marker Layers
نویسنده
چکیده
In this article, the growth and coalescence of semipolar (112̄2) oriented GaN layers, deposited on pre-structured r-plane sapphire substrates, is studied with the help of Si-doped marker layers. It has been found to be very important to adjust the shape of the initial GaN stripes by varying the growth temperature to obtain not only a smooth surface, but also a low density of basal plane stacking faults (BSFs) and threading dislocations (TDs) on the wafer surface. With the help of transmission electron microscopy (TEM) and cathodoluminescence measurements (CL), we can conclude that during growth, we need to achieve a compromise between low BSF density, low TD density, and perfect coalescence with smooth surface, free of fissures and other growth artifacts.
منابع مشابه
Improvement of MOVPE Grown (112̄2) Oriented GaN 25 Improvement of MOVPE Grown (112̄2) Oriented GaN on Pre-Structured Sapphire Substrates Using a SiNx Interlayer and HVPE Overgrowth
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