Sputter Machining of Piezoelectric Transducers

Abstract

This paper demonstrates that sputter machining can be used to obtain fundamental mode transducers or resonators for the frequency range above 100 MHz where mechanical methods of thickness reduction have low yields. Material is removed by bombarding the specimen with high-energy ions drawn from a gaseous plasma. Experimental results are given for the sputter machining of sputter-deposited zinc oxide, Y-cut lithium niobate, and Y-cut quartz. The highest fundamental resonant frequency attained was 1.8 GHz using lithium niobate, corresponding to a thickness of about 2 μ.