The innovation engine for new materials

Jorge Mata

Jorge Mata


Mechanical Engineering


University of Texas at El Paso


Katherine Mackie

Faculty Sponsor(s): 

Michael Gordon

Faculty Sponsor's Department(s): 

Chemistry and Biochemistry

Project Title: 

Characterization of magnetron sputtered WOx-TiOx thin films

Project Description: 

Magnetron sputtering has become the process of choice for the deposition of a wide range of industrially important coatings. In this work, tungsten-doped TiO2 thin films for optical and dielectric applications (e.g., anti-reflective coatings and signal filters) were synthesized using high-temperature, reactive RF magnetron sputtering at the Air Force Research Lab (AFRL), and characterized at UCSB using photoconductance measurements, Raman and Fourier transform infrared spectroscopies (FTIR). Deposition follows when target erosion occurs due to energetic particle bombardment by either reactive or non-reactive ions produced in the discharge at pressure in the mTorr range by the application of a high voltage. The effect of sputtering conditions (e.g., power delivered to the titanium and tungsten sputtering targets) on film electrical properties was investigated and found to significantly decrease film resistance (i.e., 109 →103 ohms) above a threshold tungsten source power of 80-100 W. Films were also seen to be optically active, with conductance increasing upon exposure to 514 nm laser light. It is hypothesized that this effect is due to tungsten doping on the Ti site, which results in an excess of free carriers that in turn increase conductance. Raman and FTIR reflectivity measurements have been done to explore if W modifies the vibrational characteristics of the TiO2 lattice and if the NIR reflectivity echoes the change in electrical conductivity.