Substrate Temperature Dependence of Photoresponse and Crystal Phases of TiO2 Deposited Via Dual Plane Magnetron

Light-sensitive TiO2 films are deposited on silicon via dual planar magnetron (DPM) without annealing. The DPM configuration features a mirror reactive planar magnetron sputtering system essentially driving the plasma. The series of sputtering particles bouncing back and forth within the DPM increases the titanium yield conducive for depositing TiO2 thin films on silicon. Depositions were done at varying substrate temperature from 320°C-380°C. Diffracted intensities show the formation of rutile (220), rutile (110) and anatase (101) polymorphs with rutile (110) dominant at higher temperatures. The film thickness is approximately 260nm with rough surface morphology for 360°C substrate temperature. EDX confirms the elemental structures of Ti, O and Si. The photoresponse property of the materials were obtained by subjecting the films to an illuminance test. As the substrate temperature during deposition of the film increases, the infrared transmittance increases. Oxidation leads to delay in the photoresponse. The trend of the output voltage when the film is exposed to increasing illumination varied for different substrate temperature during deposition. The films are sensitive to ultraviolet irradiation turning out three colors. The photochromism is ascribed to the presence of trivalent titanium ions in the TiO2 network. APPC12 The 12th Asia Pacific Physics Conference