HUSCAP logo Hokkaido Univ. logo

Hokkaido University Collection of Scholarly and Academic Papers >
量子集積エレクトロニクス研究センター  >
雑誌発表論文等  >

On the origin of interface states at oxide/III-nitride heterojunction interfaces

2E4971409.pdf2.99 MBPDF見る/開く

タイトル: On the origin of interface states at oxide/III-nitride heterojunction interfaces
著者: Matys, M. 著作を一覧する
Adamowicz, B. 著作を一覧する
Domanowska, A. 著作を一覧する
Michalewicz, A. 著作を一覧する
Stoklas, R. 著作を一覧する
Akazawa, M. 著作を一覧する
Yatabe, Z. 著作を一覧する
Hashizume, T. 著作を一覧する
発行日: 2016年12月14日
出版者: American Institute of Physics (AIP)
誌名: Journal of Applied Physics
巻: 120
号: 22
開始ページ: 225305
出版社 DOI: 10.1063/1.4971409
抄録: The energy spectrum of interface state density, D-it(E), was determined at oxide/III-N heterojunction interfaces in the entire band gap, using two complementary photo-electric methods: (i) photo-assisted capacitance-voltage technique for the states distributed near the midgap and the conduction band (CB) and (ii) light intensity dependent photo-capacitance method for the states close to the valence band (VB). In addition, the Auger electron spectroscopy profiling was applied for the characterization of chemical composition of the interface region with the emphasis on carbon impurities, which can be responsible for the interface state creation. The studies were performed for the AlGaN/GaN metal-insulator-semiconductor heterostructures (MISH) with Al2O3 and SiO2 dielectric films and AlxGa1-x layers with x varying from 0.15 to 0.4 as well as for an Al2O3/InAlN/GaN MISH structure. For all structures, it was found that: (i) D-it(E) is an U-shaped continuum increasing from the midgap towards the CB and VB edges and (ii) interface states near the VB exhibit donor-like character. Furthermore, D-it(E) for SiO2/AlxGa1-x/GaN structures increased with rising x. It was also revealed that carbon impurities are not present in the oxide/III-N interface region, which indicates that probably the interface states are not related to carbon, as previously reported. Finally, it was proven that the obtained D-it(E) spectrum can be well fitted using a formula predicted by the disorder induced gap state model. This is an indication that the interface states at oxide/III-N interfaces can originate from the structural disorder of the interfacial region. Furthermore, at the oxide/barrier interface we revealed the presence of the positive fixed charge (Q(F)) which is not related to D-it(E) and which almost compensates the negative polarization charge (Q(pol)(-)).
Rights: The following article appeared in Journal of Applied Physics 120, 225305 (2016) and may be found at
資料タイプ: article
出現コレクション:雑誌発表論文等 (Peer-reviewed Journal Articles, etc)

提供者: Maciej Franciszek Matys


本サイトに関するご意見・お問い合わせは repo at へお願いします。 - 北海道大学