Patent ID: 7537949

Claim:
A method of producing an optoelectronic substrate which comprises: providing a semi-conducting Group III metal nitride substrate having a Group III metal face and a prepared nitrogen face; detaching a thin layer from the prepared nitrogen face of the nitride substrate and transferring it to an auxiliary substrate to provide at least one Group III metal nitride layer thereon and form an intermediate assembly with the Group III metal face exposed and with the prepared nitrogen face of the nitride substrate positioned adjacent the auxiliary substrate; bonding the intermediate assembly to a supporting substrate; and removing the auxiliary substrate to provide an optoelectronic substrate; wherein the nitrogen face of the semi-conducting nitride substrate is obtained by polishing to have a dislocation density of less than about 10 6 cm 2 , a substrate planarity in the range of 20 micrometers and a surface roughness of less than 0.3 nm RMS measured with an atomic force microscope over a field of 1×1 μm 2 .