Monitored vacuum deposition of dielectric coatings over surface acoustic wave devices
Résumé
We report on our experience in the control of magnetron sputtering process by in-situ monitoring of a surface acoustic wave (SAW) device (resonator or delay line) electrical response during the deposition of dielectric layers on the SAW device surface. While the electrical response changes with the, growth of different layers, the response monitoring provides a useful feedback for layer thickness control in a multiple layer system. The monitoring approach is reproducible and gives physical insight into the SAW propagation changes occurring during the fabrication. It serves as a good tool for obtaining acoustic wave dispersion curves and helps in verifying theoretical and design principles of building multiple layer microwave acoustics devices. (C) 2015 Elsevier Ltd. All rights reserved.