Determination of elastic moduli of GaN epitaxial layers by microindentation technique

It is demonstrated that Young’s modulus of epitaxial gallium nitride layers can be determined by the microindentation of their growth surface. The technique is based on the solution of the Hertz problem for the elastic indentation of a steel sphere into the studied surface. It is established that the isotropic approximation applied in this case is justified and leads to the satisfactory results. The microhardness measurements of epitaxial layers are carried out.