Ti Alloyed <i>α</i>-Ga<sub>2</sub>O<sub>3</sub>: Route towards Wide Band Gap Engineering
The suitability of Ti as a band gap modifier for <inline-formula><math display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub> was investigated, taking advantage of the is...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-12-01
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| Series: | Micromachines |
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| Online Access: | https://www.mdpi.com/2072-666X/11/12/1128 |
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| author | Armin Barthel Joseph Roberts Mari Napari Martin Frentrup Tahmida Huq András Kovács Rachel Oliver Paul Chalker Timo Sajavaara Fabien Massabuau |
| author_facet | Armin Barthel Joseph Roberts Mari Napari Martin Frentrup Tahmida Huq András Kovács Rachel Oliver Paul Chalker Timo Sajavaara Fabien Massabuau |
| author_sort | Armin Barthel |
| collection | DOAJ |
| description | The suitability of Ti as a band gap modifier for <inline-formula><math display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub> was investigated, taking advantage of the isostructural <inline-formula><math display="inline"><semantics><mi>α</mi></semantics></math></inline-formula> phases and high band gap difference between Ti<sub>2</sub>O<sub>3</sub> and Ga<sub>2</sub>O<sub>3</sub>. Films of (Ti,Ga)<sub>2</sub>O<sub>3</sub> were synthesized by atomic layer deposition on sapphire substrates, and characterized to determine how crystallinity and band gap vary with composition for this alloy. We report the deposition of high quality <inline-formula><math display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>-(Ti<sub>x</sub>Ga<sub>1−x</sub>)<sub>2</sub>O<sub>3</sub> films with x = 3.7%. For greater compositions the crystalline quality of the films degrades rapidly, where the corundum phase is maintained in films up to x = 5.3%, and films containing greater Ti fractions being amorphous. Over the range of achieved corundum phase films, that is 0% ≤ x ≤ 5.3%, the band gap energy varies by ∼270 meV. The ability to maintain a crystalline phase at low fractions of Ti, accompanied by a modification in band gap, shows promising prospects for band gap engineering and the development of wavelength specific solar-blind photodetectors based on <inline-formula><math display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub>. |
| first_indexed | 2024-03-10T13:54:42Z |
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| id | doaj.art-e5f47d7ca40b46ab97ed1316a457e070 |
| institution | Directory Open Access Journal |
| issn | 2072-666X |
| language | English |
| last_indexed | 2024-03-10T13:54:42Z |
| publishDate | 2020-12-01 |
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| record_format | Article |
| series | Micromachines |
| spelling | doaj.art-e5f47d7ca40b46ab97ed1316a457e0702023-11-21T01:45:02ZengMDPI AGMicromachines2072-666X2020-12-011112112810.3390/mi11121128Ti Alloyed <i>α</i>-Ga<sub>2</sub>O<sub>3</sub>: Route towards Wide Band Gap EngineeringArmin Barthel0Joseph Roberts1Mari Napari2Martin Frentrup3Tahmida Huq4András Kovács5Rachel Oliver6Paul Chalker7Timo Sajavaara8Fabien Massabuau9Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UKSchool of Engineering, The University of Liverpool, Liverpool L69 3GH, UKDepartment of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UKDepartment of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UKDepartment of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UKErnst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, 52425 Jülich, GermanyDepartment of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UKSchool of Engineering, The University of Liverpool, Liverpool L69 3GH, UKDepartment of Physics, University of Jyväskylä, FI-40014 Jyväskylä, FinlandDepartment of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UKThe suitability of Ti as a band gap modifier for <inline-formula><math display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub> was investigated, taking advantage of the isostructural <inline-formula><math display="inline"><semantics><mi>α</mi></semantics></math></inline-formula> phases and high band gap difference between Ti<sub>2</sub>O<sub>3</sub> and Ga<sub>2</sub>O<sub>3</sub>. Films of (Ti,Ga)<sub>2</sub>O<sub>3</sub> were synthesized by atomic layer deposition on sapphire substrates, and characterized to determine how crystallinity and band gap vary with composition for this alloy. We report the deposition of high quality <inline-formula><math display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>-(Ti<sub>x</sub>Ga<sub>1−x</sub>)<sub>2</sub>O<sub>3</sub> films with x = 3.7%. For greater compositions the crystalline quality of the films degrades rapidly, where the corundum phase is maintained in films up to x = 5.3%, and films containing greater Ti fractions being amorphous. Over the range of achieved corundum phase films, that is 0% ≤ x ≤ 5.3%, the band gap energy varies by ∼270 meV. The ability to maintain a crystalline phase at low fractions of Ti, accompanied by a modification in band gap, shows promising prospects for band gap engineering and the development of wavelength specific solar-blind photodetectors based on <inline-formula><math display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub>.https://www.mdpi.com/2072-666X/11/12/1128gallium oxidewide band gap semiconductorssolar-blind detectionatomic layer depositionthin filmsalloying |
| spellingShingle | Armin Barthel Joseph Roberts Mari Napari Martin Frentrup Tahmida Huq András Kovács Rachel Oliver Paul Chalker Timo Sajavaara Fabien Massabuau Ti Alloyed <i>α</i>-Ga<sub>2</sub>O<sub>3</sub>: Route towards Wide Band Gap Engineering Micromachines gallium oxide wide band gap semiconductors solar-blind detection atomic layer deposition thin films alloying |
| title | Ti Alloyed <i>α</i>-Ga<sub>2</sub>O<sub>3</sub>: Route towards Wide Band Gap Engineering |
| title_full | Ti Alloyed <i>α</i>-Ga<sub>2</sub>O<sub>3</sub>: Route towards Wide Band Gap Engineering |
| title_fullStr | Ti Alloyed <i>α</i>-Ga<sub>2</sub>O<sub>3</sub>: Route towards Wide Band Gap Engineering |
| title_full_unstemmed | Ti Alloyed <i>α</i>-Ga<sub>2</sub>O<sub>3</sub>: Route towards Wide Band Gap Engineering |
| title_short | Ti Alloyed <i>α</i>-Ga<sub>2</sub>O<sub>3</sub>: Route towards Wide Band Gap Engineering |
| title_sort | ti alloyed i α i ga sub 2 sub o sub 3 sub route towards wide band gap engineering |
| topic | gallium oxide wide band gap semiconductors solar-blind detection atomic layer deposition thin films alloying |
| url | https://www.mdpi.com/2072-666X/11/12/1128 |
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