Abstract
Abstract
We demonstrate 1.5 μm thick buffer-free GaN layers directly on physical vapor deposited (PVD) AlN/Si templates via delayed coalescence growth. The full width of half maximum of the X-ray diffraction rocking curves for GaN (002)/(102) planes are 525/527 arcsec. The PVD-AlN with low density and large size AlN nuclei, combined with 3D growth mode of the GaN, contribute to the delayed coalescence growth and thus crack-free GaN layers. The PVD-AlN can also effectively suppress the Ga/Al diffusion and lead to a low radio frequency loss of 0.20 dB mm−1 at 10 GHz for the GaN layers.
Funder
National Key Research and Development Program of China
Key Research and Development Program of Guangdong Province
National Natural Science Foundation of China
Beijing Municipal Science and Technology Project
Subject
General Physics and Astronomy,General Engineering