20100136770 | GROUP-III METAL NITRIDE AND PREPARATION THEREOF - A method for forming a group-III metal nitride material film attached to a substrate including subjecting the substrate to an ambient pressure of no greater than 0.01 Pa, and heating the substrate to a temperature of between approximately 500° C.-800° C. The method further includes introducing a group III metal vapor to the surface of the substrate at a base pressure of at least 0.01 Pa, until a plurality of group III metal drops form on the surface, and introducing active nitrogen to the surface at a working pressure of between 0.05 Pa and 2.5 Pa, until group III metal nitride molecules form on the group III metal drops. The method also includes maintaining the working pressure and the active nitrogen until the group III metal nitride molecules diffuse into the group III metal drops, forming nitride/metal solution drops, and until the nitride/metal solution drops turn into a wetting layer on the substrate, and continuing to increase the concentration of group III metal nitride molecules in the wetting layer until all the group III metal atoms contained in the wetting layer are exhausted, and the wetting layer transforms into a group III metal nitride film. | 06-03-2010 |