SELECTIVE WET ETCHING OF LITHIUM GALLATE

Lithium gallate (LGO) is an attractive, near lattice matched substrate for the growth of GaN. In addition, LGO substrates provide a convenie nt route to forming thin films of GaN as used in substrate removal or lift-off processes. We report the wet etching of LGO substrates for th e production of GaN thin films. Two face-selective LGO etches have bee n used for the processing of substrates. The etch rate of the cation f ace is reported here for the first time and is 0.25 mu m min(-1) at 50 degrees C. The etching solution is safe and benign to most materials including metallic bonding.