Abstract
A GaN thin film was fabricated by near-atmospheric plasma-assisted chemical vapor deposition. Pure nitrogen plasma can be generated stably using an alternating pulsed voltage system that applies an alternating pulsed voltage between two parallel plate electrodes. The excited nitrogen species correspond to the N2 second positive system. Ionic molecular species, which cause film damage, were not observed by optical emission spectrum analysis. Using this plasma as a nitrogen source, metalorganic chemical vapor deposition of GaN thin mm was carried out under a nitrogen partial pressure of 40 kPa and substrate temperature of 400oC. The quality of the GaN thin film was analyzed by means of 2-dimensional X-ray diffraction and X-ray pole figure measurement. The measurements revealed that the film was epitaxial with a 30o rotation of the unit cell with respect to (0001) sapphire in the (0001) basal plane.
