Significant increase in conduction band discontinuity due to solid phase epitaxy of Al2O3 gate insulator films on GaN semiconductor

S. Toyoda, T. Shinohara, H. Kumigashira, M. Oshima, Y. Kato

Research output: Contribution to journalArticle

42 Citations (Scopus)

Abstract

We have investigated band discontinuities and chemical structures of Al2O3 gate insulator films on n-type GaN semiconductor by photoemission and x-ray absorption spectroscopy. It is found that the solid phase epitaxy at the GaN crystal during annealing procedures at 800 °C leads to phase transformation of Al2O3 films from amorphous to crystalline. Changes in crystallographic structures closely correlate with the significant increase in conduction band discontinuity at the Al 2O3/GaN interface, which suggests that epitaxial Al 2O3 films on GaN semiconductor, free from grain boundaries of Al2O3 polycrystalline, hold the potential for high insulation performance.

Original languageEnglish
Article number231607
JournalApplied Physics Letters
Volume101
Issue number23
DOIs
Publication statusPublished - 2012 Dec 3
Externally publishedYes

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Fingerprint Dive into the research topics of 'Significant increase in conduction band discontinuity due to solid phase epitaxy of Al<sub>2</sub>O<sub>3</sub> gate insulator films on GaN semiconductor'. Together they form a unique fingerprint.

  • Cite this