Effects of native defects on properties of low temperature grown, non-stoichiomtric gallium nitride. (25th August 2015)

• Record Type: Journal Article
• Authors: Yu, K M; Ting, Min; Novikov, S V; Collin, Clement; Sarney, W L; Svensson, S P; Luce, A V; Denlinger, J D; Walukiewicz, W; Foxon, C T
• Is Part Of: Journal of physics. Volume 48:Number 38(2015)
• Publication Date: 2015-08-25
• Subjects: gallium nitride -- low temperature MBE -- optical properties -- non-stoichiometry -- native defects; Physics -- Periodicals; 530
• DOI: 10.1088/0022-3727/48/38/385101
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: The properties of GaN thin films grown by molecular beam epitaxy at temperatures from 80 to 500 °C under a wide range of Ga:N flux ratios are studied. We found that at growth temperatures as low as ~80 °C, GaN films still have a polycrystalline, columnar morphology with c -axis preferred orientation. Soft x-ray absorption and emission and optical absorption measurements on Ga-rich samples suggest the presence of a partially occupied GaN antisite defect band located at ~1.2 eV below the conduction band minimum. P-type conductivity observed in this LTMBE Ga-rich GaN is consistent with transport within this partially occupied defect band.