Salvato in:
| Autori principali: | , , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2025
|
| Soggetti: | |
| Accesso online: | https://arxiv.org/abs/2504.17976 |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866908368268951552 |
|---|---|
| author | Rajan, Vishwa Krishna Chao, Jeremy Taylor, Sydney Wang, Liping |
| author_facet | Rajan, Vishwa Krishna Chao, Jeremy Taylor, Sydney Wang, Liping |
| contents | Thermochromic vanadium dioxide thin films have attracted much attention recently for constructing variable-emittance coatings upon its insulator-metal phase transition for dynamic thermal control. However, fabrication of high-quality vanadium dioxide thin films in a cost-effective way is still a challenge. In addition, the phase transition temperature of vanadium dioxide is around 68°C, which is higher than most of terrestrial and extraterrestrial applications. In this study, we report the fabrication and characterization of tungsten-doped vanadium dioxide thin films with lowered phase transition temperatures via co-sputtering, furnace oxidation and thermal annealing processes for wider application needs. The doping is achieved by co-sputtering of tungsten and vanadium targets while the doping level is varied by carefully controlling the sputtering power for tungsten. Doped thin film samples of 30-nm thick with different tungsten atomic concentrations are prepared by co-sputtering onto undoped silicon wafers. Optimal oxidation time of 4 hours is determined to reach full oxidation in an oxygen-rich furnace environment at 300°C. Systematic thermal annealing study is carried out to find the optimal annealing temperature and time. By using an optical cryostat coupled to an infrared spectrometer, the temperature-dependent infrared transmittance of fully annealed tungsten-doped vanadium dioxide thin films are measured in a wide temperature range from -60°C to 100°C. The phase transition temperature is found to decrease at 24.5°C per at.% of tungsten doping, and the thermal hysteresis between heating and cooling shrinks at 5.5°C per at.% from the fabricated vanadium dioxide thin films with tungsten doping up to 4.1 at.%. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2504_17976 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Lowering Insulator-to-Metal Transition Temperature of Vanadium Dioxide Thin Films via Co-Sputtering, Furnace Oxidation and Thermal Annealing Rajan, Vishwa Krishna Chao, Jeremy Taylor, Sydney Wang, Liping Materials Science Optics Thermochromic vanadium dioxide thin films have attracted much attention recently for constructing variable-emittance coatings upon its insulator-metal phase transition for dynamic thermal control. However, fabrication of high-quality vanadium dioxide thin films in a cost-effective way is still a challenge. In addition, the phase transition temperature of vanadium dioxide is around 68°C, which is higher than most of terrestrial and extraterrestrial applications. In this study, we report the fabrication and characterization of tungsten-doped vanadium dioxide thin films with lowered phase transition temperatures via co-sputtering, furnace oxidation and thermal annealing processes for wider application needs. The doping is achieved by co-sputtering of tungsten and vanadium targets while the doping level is varied by carefully controlling the sputtering power for tungsten. Doped thin film samples of 30-nm thick with different tungsten atomic concentrations are prepared by co-sputtering onto undoped silicon wafers. Optimal oxidation time of 4 hours is determined to reach full oxidation in an oxygen-rich furnace environment at 300°C. Systematic thermal annealing study is carried out to find the optimal annealing temperature and time. By using an optical cryostat coupled to an infrared spectrometer, the temperature-dependent infrared transmittance of fully annealed tungsten-doped vanadium dioxide thin films are measured in a wide temperature range from -60°C to 100°C. The phase transition temperature is found to decrease at 24.5°C per at.% of tungsten doping, and the thermal hysteresis between heating and cooling shrinks at 5.5°C per at.% from the fabricated vanadium dioxide thin films with tungsten doping up to 4.1 at.%. |
| title | Lowering Insulator-to-Metal Transition Temperature of Vanadium Dioxide Thin Films via Co-Sputtering, Furnace Oxidation and Thermal Annealing |
| topic | Materials Science Optics |
| url | https://arxiv.org/abs/2504.17976 |