Thermal behaviour and reliability of solidly mounted Bulk Acoustic Wave Duplexers under high power RF loads

Abstract

In this paper, the reliability requirements, thermal behaviour and failure mechanisms of solidly mounted Bulk Acoustic Wave (BAW) filters are studied. High power RF stress measurements are presented where the evolution of the surface damage of the BAW filters as a function of stress time is analysed by optical height profiling. Two different metal stacks were used. The main failure mechanism for BAW filters during high RF power stress is proposed to be acoustomigration. By comparing the stress measurements to the requirements, excellent reliability of NXP's BAW duplexers is proven.