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.
Authors
- Indra Subedi (ORCID: https://orcid.org/0000-0003-2300-6010)
- Kyeongjae Cho (ORCID: https://orcid.org/0000-0003-2698-7774)
- Peter A. van Aken (ORCID: https://orcid.org/0000-0003-1890-1256)
- C. T. Parzyck (ORCID: https://orcid.org/0000-0002-3835-7115)
- Debdeep Jena (ORCID: https://orcid.org/0000-0002-4076-4625)
- Kathy Azizie (ORCID: https://orcid.org/0000-0003-4021-4399)
- L. Kalaydjian (ORCID: https://orcid.org/0009-0008-0844-0402)
- Nikolas J. Podraza (ORCID: https://orcid.org/0000-0002-3155-559X)
- Huili Grace Xing (ORCID: https://orcid.org/0000-0002-2709-3839)
- Darrell G. Schlom (ORCID: https://orcid.org/0000-0003-2493-6113)
- Y. Eren Suyolcu (ORCID: https://orcid.org/0000-0003-0988-5194)
- Qi Song (ORCID: https://orcid.org/0000-0002-1254-4131)
- Felix V. E. Hensling (ORCID: https://orcid.org/0000-0003-3852-7214)
- Patrick Vogt (ORCID: https://orcid.org/0000-0002-8800-8706)
- Kyle Shen (ORCID: https://orcid.org/0000-0001-6976-3434)
- Abdullah Al Mamun (ORCID: https://orcid.org/0000-0002-8861-6103)
- Bennett J. Cromer (ORCID: https://orcid.org/0000-0001-6492-7401)
- Jisung Park (ORCID: https://orcid.org/0000-0002-6305-7560)
Institutions
- The University of Texas at Dallas (US)
- Cornell University (US)
- Laboratoire de physique des Solides (FR)
- SLAC National Accelerator Laboratory (US)
- Max Planck Institute for Solid State Research (DE)
- Center for Nanoscale Science and Technology (US)
- Leibniz Institute for Crystal Growth (DE)
- New York State College of Veterinary Medicine (US)
- University of Toledo (US)
Publication Details
- Journal
- APL Materials
- Published
- 2025-11-01
- DOI
- https://doi.org/10.1063/5.0274229
- Citations
- 1
- Primary Topic
- Ga2O3 and related materials
- Type
- article
- Field-Weighted Citation Impact
- 0.43
Funders
- National Science Foundation
- Cornell Center for Materials Research
- Materials Research Science and Engineering Center, Harvard University
- Division of Materials Research
- Air Force Office of Scientific Research
- Air Force Research Laboratory