On the influence of solution density on the formation of macroscopic defects in the liquid phase epitaxy of GaN

Abstract

This paper reports on a new simple method for avoiding particle-induced macroscopic defects using the liquid phase epitaxy (LPE) of GaN as an example. In a series of growth experiments by LPE of GaN it is demonstrated that the number of particle-induced macrodefects in the epitaxial layers correlates strongly and reproducibly with the density of the solution. In solutions with a density higher than that of the deleterious particles, the particles float on the solution and hence are hindered to get into contact with the seed, which is placed at the bottom of the crucible. Consequently, so-called depressions — a typical particle-induced defect in GaN–LPE layers — are avoided. The principle of avoiding the formation of macroscopic defects originating from particles by adapting the density of the solution (density criterion) should be generally applicable to solution growth processes, regardless of the material system.