Pulsed lateral epitaxial overgrowth of aluminum nitride on sapphire substrates.

Authors :: Chen, Z.
Fareed, R. S. Qhalid
Gaevski, M.
Adivarahan, V.
Yang, J. W.
Khan, Asif
Mei, J.
Ponce, F. A.
Source :: Applied Physics Letters. 8/21/2006, Vol. 89 Issue 8, p081905. 3p. 2 Color Photographs, 1 Black and White Photograph, 1 Graph.
Publication Year :: 2006
Abstract: The authors report on pulsed lateral epitaxial overgrowth of aluminum nitride films on basal plane sapphire substrates. This approach, at temperatures in excess of 1150 °C, enhanced the adatom migration, thereby significantly increasing the lateral growth rates. This enabled a full coalescence in wing regions as wide as 4–10 μm. Atomic force microscopy and cross-section transmission electron microscopy were used to establish the reduction of threading dislocations in the lateral growth. Cross-sectional monochromatic cathodoluminescence and photoluminescence measurements confirmed the improved optical properties of the laterally overgrown aluminum nitride films. [ABSTRACT FROM AUTHOR]