open access

https://hdl.handle.net/2115/73850

Effect of Insertion of Ultrathin Al2O3 Interlayer at Metal/GaN Interfaces

英語

Schottky barriers

2018-05

Wiley-Blackwell

Physica status solidi B-basic solid state physics

255(5)

1700382

Fermi level depinning at a metal/semiconductor interface by using an ultrathin insulating interlayer to block the penetration of the metal wave function into the semiconductor is examined on GaN. A Si-doped n-type GaN epitaxial layer on a freestanding GaN substrate is used as the host material. For the samples with an interlayer, an ultrathin Al2O3 layer of 1nm thickness is deposited by atomic layer deposition. As the metal layers, Ag, Cu, Au, Ni, and Pt are deposited by electron beam evaporation. Samples without an interlayer are also fabricated for comparison. The apparent change in current-voltage characteristics of the Schottky barrier diodes with the insertion of the interlayer is dependent on the electrode metal. However, the apparent Schottky barrier height (SBH) for the samples with the interlayer is almost constant and independent of the metal electrode, although the samples without an interlayer exhibit a moderate dependence of the SBH on the metal work function. Thus, the pinning becomes stronger upon the insertion of the interlayer, although blocking of the metal wave function by using an ultrathin insulator is expected to lead to depinning.

学術雑誌論文

Accepted Manuscript

This is the peer reviewed version of the following article: Physica status solidi B-basic solid state physics 2018, 255, 1700382, which has been published in final form at https://doi.org/10.1002/pssb.201700382. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.

0370-1972