GaN single crystal habits and their relation to GaN growth under high pressure of nitrogen

Abstract

In the growth of GaN from nitrogen dissolved in Ga under high N2 pressure, two main habits are observed: plate-like and needle-like. The plate-like crystals can be divided into those having (0001), (0001̄) and {101̄0} faces and those with the additional {l01̄1} and {101̄2} faces. The needle-like crystals belong to three classes: with or without (0001) faces and a third with unusual, star-like needles. The plate-like and needle-like habits and transformation between these habits are discussed in greater detail. It is shown that it is possible to evaluate the relative growth rates corresponding to such transitions.