[8p-Z02-1~8] Materials Science and Advanced Electronics Created by Singularity of Nitride Semiconductors -Frontiers in defect physics: Concerted approach of characterization and theory-

[8p-Z02-2] Conversion from p-type GaN to n-type by Complexes of Screw Dislocations and Mg: First-principles Calculation and Atom Probe Tomography Analysis

〇Yosuke Harashima¹, Takashi Nakano², Kenta Chokawa¹, Kenji Shiraishi^1,2, Atsushi Oshiyama¹, Yoshihiro Kangawa^3,1, Shigeyoshi Usami², Norihito Mayama⁴, Kazuya Toda⁴, Atsushi Tanaka¹, Yoshio Honda^1,2, Hiroshi Amano^1,2 (1.IMaSS, Nagoya Univ., 2.Grad. Sch. Engineering, Nagoya Univ., 3.RIAM, Kyushu Univ., 4.Toshiba Nanoanalysis Corp.)

Keywords:semiconductor, dislocation, first-principles calculation

For realization of GaN power semiconductor devices, understanding of a microscopic mechanism of the leakage current is required.In this study, we perform first-principles electronic-structure calculations for complexes of screw dislocations and an Mg atom, and three-dimensional atom probe tomography analysis for the microstructure of the leakage spot in the GaN p-n diode. These results provide a picture in which the complexes of the screw dislocation and Mg locally forms an n-type region due to elevation of the electronic level. The appearance of this region results in local formation of an n-n junction and can be an origin of the leakage current.