Characterization of substrate off-angle effects for high-quality homoepitaxial CVD diamond films

• Published in: Diamond and related materials 2008-04, Vol.17 (4), p.435-439
• Main Authors: Maida, Osamu, Miyatake, Hidetaka, Teraji, Tokuyuki, Ito, Toshimichi
• Format: Article
• Language: English
• Subjects: Cathodoluminescence; Cathodoluminescence, ionoluminescence; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Diamond film; Exact sciences and technology; Excitons; Fullerenes and related materials; diamonds, graphite; Homoepitaxy; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Other luminescence and radiative recombination; Photoluminescence; Physics; Plasma CVD; Specific materials; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2007.12.052

We have studied the substrate off-angle effects for the crystalline quality of the homoepitaxial diamond films mainly by using steady-state cathodoluminescence (CL) and time-resolved photoluminescence (PL) measurements. By means of the microwave plasma chemical vapor deposition method under high-power microwave power with high methane concentrations, the homoepitaxial diamond films were grown on the high-pressure/high-temperature-synthesized (HPHT) Ib (001) substrates inclined along either or direction by different off-angles ranging from 2° to 5°. In spite of high growth rates, we have succeeded in improving crystalline quality by employing the HPHT substrates with considerably large off-angles. Both steady-state CL and time-resolved PL measurements clearly indicate that larger off-angles lead to better crystalline quality of the homoepitaxial film, suggesting that further improvements in crystalline quality can be expected when using substrates having even larger off-angles.