Etch Processing of Bulk and Surface Wave Devices

Etch processing of bulk wave devices is a developing technique where the upper frequency limitation of the mechanical processes can no longer be applied. However, the use of chemical or plasma processes imposes other disciplines with regard to the quality of the material and to the mechanical processes preceding the final etch. This paper discusses the techniques and the results achieved in the manufacture of bulk wa-!e resonators up to l50 MHz in the fundamental mode using the AT-cut.