| 摘要 |
PROBLEM TO BE SOLVED: To enable to reduce the cost without hurting the reliability of a device by means of a simple predicting process by using strong reducing liquid at the time of washing the surface of a wafer of a piezoelectric body. SOLUTION: A metallic thin film such as an aluminum thin film or a silver thin film, etc., is formed on the front surface of the wafer 10 consisting of LBO. Besides, a photo resistor is coated on the thin film, exposed with a photo mask and developed to form a resist pattern on the wafer. Then, an electrode pattern is formed by dry etching, etc., and washed by the strong reducing electrolyte. A resist surface is stripped by an organic solvent. When multiple formed surface acoustic wave devices are divided by the cutter 14 of a dicing device after that, the cutting is executed into plural surface acoustic wave device substrates while supplying strong reducing liquid. PH is large as about 11, an electron movility is small in the strong reducing liquid and LBO is not dissolved so that a center frequency does not fluctuate since a groove is not formed between comb electrodes 12. |
