Raman Scattering and Photoluminescence of Mg-Implanted GaN Films

✍ Scribed by Lianshan Wang; Soo Jin Chua; Wenhong Sun

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 85 KB
• Volume: 228
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/1521-3951(200111)228:2<449::aid-pssb449>3.0.co;2-2

✦ Synopsis

As-grown highly resistive (>10 7 W cm) GaN samples were exposed to implantation of 24 Mg + ions with the energy of 120 keV and dose of 2 Â 10 14 cm --2 . Isochronal rapid thermal annealing (RTA) was carried out for the Mg-implanted samples at 850, 950 and 1050 C, respectively. Under z(x, x)z 0 backscattering configuration, A 1 (LO) and E 2 (high) Raman modes of 735 cm --1 and 569 cm --1 , respectively, were observed for the as-grown and Mg-implanted samples, but a Raman mode of 662 cm --1 appeared only in the implanted samples. We tentatively assigned the mode to a Mg acceptor-related vibration mode. Room temperature photoluminescence revealed that the as-grown films displayed a strong yellow luminescence of 560 nm (2.21 eV), while Mg-implanted samples only exhibited a broad blue-violet luminescence peaking at 400 nm (%3.11 eV) which decreased with increasing RTA temperature. Our observation supported the Ga vacancy model responsible for yellow luminescence.