GaN films deposited by planar magnetron sputtering

The crystal orientation of GaN films deposited on fused quartz substrates by rf planar magnetron sputtering using a mesh to guard against plasma exposure was investigated by X-ray diffraction. Sample films were deposited at constant N 2 gas pressure and input power at a range of substrate temperatures between 84°C and 600°C. It was found that GaN films with good crystal orientation can be produced by rf sputtering with the c -axis of GaN crystals oriented normal to the substrate surface in almost all films produced. The crystal 0 0·2 orientation was good at substrate temperatures exceeding 300°C, however, films deposited at 600°C peeled from the substrate. The fine mesh installed to protect the film from exposure to plasma was found to be very useful for depositing films with a good crystal orientation of 0 0·2, and the best crystal orientation was realized for a film deposited by sputtering with a target to mesh separation of 30 mm.