DIAMOND SUBSTRATE FOR SURFACE ACOUSTIC WAVE DEVICE AND SURFACE ACOUSTIC WAVE DEVICE

摘要

PURPOSE: A diamond substrate for a surface acoustic wave device and the surface acoustic wave device are provided to be capable of increasing the propagation speed of surface acoustic wave and reducing propagation loss. CONSTITUTION: A surface acoustic wave device(100) is provided with a diamond substrate(200), a piezoelectric thin film(120) formed at the upper portion of the diamond substrate, and a plurality of comb type electrodes(140,160) formed at the predetermined upper portions of the resultant structure. At this time, the diamond substrate is made of a silicon wafer(220) and a diamond thin film(240). Preferably, a center layer is formed between the diamond substrate and the piezoelectric thin film. Preferably, the diamond thin film is formed by carrying out one selected from a group consisting of a CVD(Chemical Vapor Deposition) process, a heat filament CVD process, a microwave plasma CVD process, a high frequency plasma CVD process, and DC(Direct Current) plasma jet process.