Journal of Crystal Growth, Vol.367, 88-93, 2013
Multifacet semipolar formation by controlling the groove depth via lateral sidewall epitaxy
We demonstrate InxGa1-xN/GaN light emitting diode structures with different sets of multifacet semipolar formation grown laterally on m-plane sidewalls formed by stripe patterning on preliminary grown c-plane GaN template. It was found that regrowth on shallow side walls within the GaN template resulted in a single semipolar (1 (1) over bar 01) facet, while deeper side walls led to multifacet semipolar formation. Very deep etching through the entire GaN template reaching the underlying sapphire substrates resulted in a combination of semipolar (1 (1) over bar 01) and nonpolar (1 (1) over bar 00) facets. The results indicate that the depth of the groove patterning can be used as a tool for controlling the set of semipolar facet formation. In addition, the growth rate in different crystallographic directions was studied and possible factors affecting the growth rates are discussed. Published by Elsevier B.V.