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Title: Growth of tetragonal PtO by molecular-beam epitaxy and its integration into β-Ga2O3 Schottky diodes
We demonstrate the epitaxial growth of tetragonal platinum monoxide (PtO) on MgO, TiO2, and β-Ga2O3 single-crystalline substrates by ozone molecular-beam epitaxy. We provide synthesis routes and derive a growth diagram under which PtO films can be synthesized by physical vapor deposition. A combination of electrical transport and photoemission spectroscopy measurements, in conjunction with density functional theory calculations, reveal PtO to be a degenerately doped p-type semiconductor with a bandgap of Eg ≈ 1.6 eV. Spectroscopic ellipsometry measurements are used to extract the complex dielectric function spectra, indicating a transition from free-carrier absorption to higher photon energy transitions at E ≈ 1.6 eV. Using tetragonal PtO as an anode contact, we fabricate prototype Schottky diodes on n-type Sn-doped β-Ga2O3 substrates and extract Schottky barrier heights of ϕB > 2.2 eV.  more » « less
Award ID(s):
2039380
PAR ID:
10671053
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
AIP Publishing
Date Published:
Journal Name:
APL Materials
Volume:
13
Issue:
11
ISSN:
2166-532X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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