抄録
The float polishing process is widely recognized for its ability to produce surfaces to atomic conformance, with extremely high flatness. AT-cut, premium-Q, cultured, crystalline-quartz acoustic resonators were fabricated recently by a float polishing process. The study was conducted to maximize the stress-fracture threshold, by optimizing the fabrication process to eliminate sub-surface damage. Polishing medium and removal were examined as variables. The best results obtained, for quartz resonators polished with colloidal silica, are a surface roughness of less than 0.2-nm rms by AFM, and a near-bulk value of pre-fracture flexural strength of 620 MPa. This indicates that float polishing produces a factor of 10 improvement in the strength and the overall quality of quartz over the conventional CeO_2 process.
