Large-Area Mosaic Diamond Films Approaching Single-Crystal Quality

摘要

The seeding for large-area mosaic diamond films approaching single-crystalquality is described. The technique includes patterned etching of relief structures in Si substrates, deposition from a slurry and orientation of macroscopic diamond seed crystals in the structures, and chemical vapor deposition overgrowth of the diamond seeds to form a continuous film. The film comprises 100 micrometer single crystals, which are separated by low-angle grain boundaries of a few degrees or less. We believe that these low angle grain boundaries will not affect the electrical properties of majority carrier devices. Despite diamond's excellent electrical properties, the inability to obtain large area single crystal diamond films has limited the development of diamond device technology. Several attempts to obtain such films by heteroepitaxy have been unsuccessful, and only recently has heteroepitaxy over very limited areas on cubic BN,2Si,3,4Ni,5 and Cu6 been reported.