Electrical and light-emitting properties from (111)-oriented homoepitaxial diamond p– i– n junctions

• Published in: Diamond and related materials 2009-05, Vol.18 (5), p.764-767
• Main Authors: Makino, Toshiharu, Ri, Sung-Gi, Tokuda, Norio, Kato, Hiromitsu, Yamasaki, Satoshi, Okushi, Hideyo
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Contact resistance, contact potential; Cross-disciplinary physics: materials science; rheology; Diamond; Electrical properties of specific thin films; Electrical property; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport in interface structures; Electronic transport phenomena in thin films and low-dimensional structures; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; Light emission; Materials science; p-i-n junction; Physics; Specific materials
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2009.01.016

We have succeeded in fabricating a (111)-oriented diamond p– i– n junction with high crystalline quality intrinsic layer and with low series resistance. The series resistance of this diamond p– i– n junction was improved by decreasing the resistivity and specific contact resistance of n-type layer, which is allowed to inject higher current while maintaining lower junction temperature. Current density–voltage characteristics showed a rectification ratio of 10 6 at ± 15 V at room temperature. A clear ultraviolet emission at around 235 nm due to free exciton recombination was observed at a forward current, while the broad visible light emission from deep levels was significantly suppressed. Moreover, stronger excitonic emission by two orders of magnitude than that of (001)-oriented diamond p–i–n junctions with high series resistance was realized.