- 著者
-
橋詰 保
谷田部 然治
佐藤 威友
- 出版者
- 公益社団法人 日本表面科学会
- 雑誌
- 表面科学 (ISSN:03885321)
- 巻号頁・発行日
- vol.35, no.2, pp.96-101, 2014-02-10 (Released:2014-02-19)
- 参考文献数
- 13
Interface properties of GaN-based heterostructures have been characterized. Schottky contacts on dry-etched n-GaN layers showed leaky I-V characteristics. An anneal process at 400°C was effective in recovering the rectifying characteristics. To characterize interface properties of Al2O3 insulated gates on AlGaN/GaN structures with and without the inductively coupled plasma (ICP) etching of AlGaN, we have developed a C-V calculation method taking into account electronic state charges at the Al2O3/AlGaN interface and a photoassisted C-V technique utilizing photons with energies less than the bandgap of AlGaN. It was found that the ICP etching caused the monolayer-level interface roughness, disorder of the chemical bonds and formation of various types of defect complexes at the AlGaN surface, resulting in poor C-V characteristics due to high-density interface states at the Al2O3/AlGaN interface.