Substrate temperature dependence of photoresponse and crystal phases of TiO2 deposited via dual planar magnetron

• Main Authors: Villamayor, Michelle Marie S., Wada, Motoi, Ramos, Henry J.
• Format: text
• Published: Animo Repository 2014
• Subjects: Titanium dioxide; Plasma-enhanced chemical vapor deposition; Physics
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/11593
• Institution: De La Salle University

Light-sensitive TiO2 films are deposited on silicon via dual planar magnetron (DPM) without post-deposition 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. 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 is enhanced at higher temperatures. The deposition rate is ~1.08 nm/min and has a rough surface morphology. EDX confirms the elemental presence of Ti, O and Si. Comparison between substrate heating of 340 ͦ C and 360 ͦ C shows that the higher the substrate temperature, the higher the output voltage of the film when exposed to light. Change in the film colors from green-blue-violet-purple is attributed to the prevalence of rutile as temperature is increased. The films are sensitive to ultraviolet irradiation fluorescing three colors during exposure. The photochromism is ascribed to the presence of trivalent titanium ions in the TiO2 network.