| 摘要 |
PURPOSE:To prevent the generation of the lack of a progressive electrode pattern and the increment of less and to improve the reliability of the titled device by forming an anodized layer on one surface of crossed reed screen electrode fingers. CONSTITUTION:After forming an exciting electrode 2 and a reflecting electrode 3 on one main surface of a piezoelectric base plate 1 by photoetching method or the like, voltage including a DC component is impressed between the common reed screen electrode fingers 9a, 9b for exciting electrode 2. When rhe exciting electrode 2 is brought into reaction with impure ions or the like, the surface of the reed screen electrode finger 9a is anodized and the anodized layer 12 is formed. Therefore, the lack or loss of an electrode pattern, etc. are completely exposed until the check of chipping, so that the quality is accurately discriminated and defective products after shipping is not generated by selecting anode oxidation. |
