Rapid Thermal Annealing for Surface Optimisation of ZnO Substrates for MBE-Grown Oxide Two-Dimensional Electron Gases
Two-dimensional electron gases (2DEGs) at the ZnO/ZnMgO interface are promising for applications in spintronics and quantum computing due to the combination of low spin-orbit coupling and high electron mobility. Growing high mobility 2DEGs requires high quality substrates with low impurity densities...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-09-01
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| Series: | Crystals |
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| Online Access: | https://www.mdpi.com/2073-4352/10/9/776 |
| _version_ | 1797554851191717888 |
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| author | Matthew J. Sparks Oscar W. Kennedy Paul A. Warburton |
| author_facet | Matthew J. Sparks Oscar W. Kennedy Paul A. Warburton |
| author_sort | Matthew J. Sparks |
| collection | DOAJ |
| description | Two-dimensional electron gases (2DEGs) at the ZnO/ZnMgO interface are promising for applications in spintronics and quantum computing due to the combination of low spin-orbit coupling and high electron mobility. Growing high mobility 2DEGs requires high quality substrates with low impurity densities. In this work we demonstrate a ZnO substrate sample treatment combining high temperature rapid thermal annealing and chemical etching to improve the surface quality for the subsequent growth of 2DEGs. This process enables the growth of a 2DEG with low-temperature mobility of <inline-formula><math display="inline"><semantics><mrow><mn>4.8</mn><mo>×</mo><msup><mn>10</mn><mn>4</mn></msup></mrow></semantics></math></inline-formula> cm<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>2</mn></msup></semantics></math></inline-formula>V<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></semantics></math></inline-formula>s<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></semantics></math></inline-formula>. An unannealed control sample shows a scattering rate at least three times greater than the annealed sample. |
| first_indexed | 2024-03-10T16:37:58Z |
| format | Article |
| id | doaj.art-913b6671cd95465b8a3f5953c780df2f |
| institution | Directory Open Access Journal |
| issn | 2073-4352 |
| language | English |
| last_indexed | 2024-03-10T16:37:58Z |
| publishDate | 2020-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Crystals |
| spelling | doaj.art-913b6671cd95465b8a3f5953c780df2f2023-11-20T12:14:51ZengMDPI AGCrystals2073-43522020-09-0110977610.3390/cryst10090776Rapid Thermal Annealing for Surface Optimisation of ZnO Substrates for MBE-Grown Oxide Two-Dimensional Electron GasesMatthew J. Sparks0Oscar W. Kennedy1Paul A. Warburton2London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, UKLondon Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, UKLondon Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, UKTwo-dimensional electron gases (2DEGs) at the ZnO/ZnMgO interface are promising for applications in spintronics and quantum computing due to the combination of low spin-orbit coupling and high electron mobility. Growing high mobility 2DEGs requires high quality substrates with low impurity densities. In this work we demonstrate a ZnO substrate sample treatment combining high temperature rapid thermal annealing and chemical etching to improve the surface quality for the subsequent growth of 2DEGs. This process enables the growth of a 2DEG with low-temperature mobility of <inline-formula><math display="inline"><semantics><mrow><mn>4.8</mn><mo>×</mo><msup><mn>10</mn><mn>4</mn></msup></mrow></semantics></math></inline-formula> cm<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>2</mn></msup></semantics></math></inline-formula>V<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></semantics></math></inline-formula>s<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></semantics></math></inline-formula>. An unannealed control sample shows a scattering rate at least three times greater than the annealed sample.https://www.mdpi.com/2073-4352/10/9/776ZnOheterostructure2DEGmolecular beam epitaxysemiconductor II-VI material |
| spellingShingle | Matthew J. Sparks Oscar W. Kennedy Paul A. Warburton Rapid Thermal Annealing for Surface Optimisation of ZnO Substrates for MBE-Grown Oxide Two-Dimensional Electron Gases Crystals ZnO heterostructure 2DEG molecular beam epitaxy semiconductor II-VI material |
| title | Rapid Thermal Annealing for Surface Optimisation of ZnO Substrates for MBE-Grown Oxide Two-Dimensional Electron Gases |
| title_full | Rapid Thermal Annealing for Surface Optimisation of ZnO Substrates for MBE-Grown Oxide Two-Dimensional Electron Gases |
| title_fullStr | Rapid Thermal Annealing for Surface Optimisation of ZnO Substrates for MBE-Grown Oxide Two-Dimensional Electron Gases |
| title_full_unstemmed | Rapid Thermal Annealing for Surface Optimisation of ZnO Substrates for MBE-Grown Oxide Two-Dimensional Electron Gases |
| title_short | Rapid Thermal Annealing for Surface Optimisation of ZnO Substrates for MBE-Grown Oxide Two-Dimensional Electron Gases |
| title_sort | rapid thermal annealing for surface optimisation of zno substrates for mbe grown oxide two dimensional electron gases |
| topic | ZnO heterostructure 2DEG molecular beam epitaxy semiconductor II-VI material |
| url | https://www.mdpi.com/2073-4352/10/9/776 |
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