6533b872fe1ef96bd12d2f42
RESEARCH PRODUCT
Correlation between in situ structural and optical characterization of the semiconductor-to-metal phase transition of VO2 thin films on sapphire
Roberto MacalusoEmilija PetronijevicTiziana CescaGiovanni MatteiGrigore LeahuRoberto Li VotiConcita SibiliaMauro MoscaCarlo ScianGianmario Cesarinisubject
010302 applied physicsPhase transitionMaterials scienceTransition temperatureAnalytical chemistryPulsed laser depositionphase change material; VO202 engineering and technologyVO2 thin films021001 nanoscience & nanotechnology01 natural sciencesSettore ING-INF/01 - ElettronicaPulsed laser depositionTetragonal crystal systemVO20103 physical sciencesSapphireThermal hysteresisGeneral Materials ScienceCrystalliteThin film0210 nano-technologyphase change materialMonoclinic crystal systemSemiconductor-to-metal (SMT) transitiondescription
A detailed structural investigation of the semiconductor-to-metal transition (SMT) in vanadium dioxide thin films deposited on sapphire substrates by pulsed laser deposition was performed by in situ temperature-dependent X-ray diffraction (XRD) measurements. The structural results are correlated with those of infrared radiometry measurements in the SWIR (2.5-5 μm) and LWIR (8-10.6 μm) spectral ranges. The main results indicate a good agreement between XRD and optical analysis, therefore demonstrating that the structural transition from monoclinic to tetragonal phases is the dominating mechanism for controlling the global properties of the SMT transition. The picture that emerges is a SMT transition in which the two phases (monoclinic and tetragonal) coexist during the transition. Finally, the thermal hysteresis, measured for thin films with different thickness, showed a clear dependence of the transition temperature and the width of the hysteresis loop on the film thickness and on the size of the crystallites.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2020-01-01 |