[20p-H121-1~24] 15.4 III-V-group nitride crystals

△ [20p-H121-1] Characterization of GaN layer using THz ellipsometry and its verification by cross-sectional observation

〇KOHEI TACHI¹, Shiho Asagami¹, Takashi Fujii^1,3, Tsutomu Araki¹, Yasushi Nanishi¹, Takeshi Nagashima², Toshiyuki Iwamoto³, Yukinori Sato³, Naotake Morita⁴, Ryuichi Sugie⁴, Satoshi Kamiyama⁵ (1.Ritsumeikan Univ., 2.Setsunan Univ., 3.PNP, 4.TRC, 5.Meijo Univ.)

Keywords:THz ellipsometry,GaN,electrical properties

Electrical properties of epitaxial layer about nitride semiconductor devices are measured by Hall effect measurements or CV measurements. Because of difficulties in fabricating electrodes on nitride semiconductor, non-destructive and contactless measurement techniques for electrical properties are needed. As one of the optical methods, terahertz time domain spectroscopic ellipsometry (THz-TDSE) is proposed. We can obtain electrical properties and thickness by this method. In my presentation, I confirm the varidty of this method about n-type GaN on sapphire substrate using cross-sectional observation.