| 摘要 |
PURPOSE:To prevent the ''slack'' of a sound absorbing pattern which is caused during the drying and thermal processes after a screen print, by having the glow discharge of a substrate after an electrode pattern is formed and removing the contamination due to the fats and oils, etc. to clean the surface of the substrate. CONSTITUTION:The pass characteristics of a filter is affected directly by the positional accuracy of a sound absorbing film 5 existing through a multistrip coupler 3 and at the same time receives the effect of exitation of an undesired wave in accordance with the positional accuracy of the bent part of a sound absorbing film 6. Then the piezoelectric crystal wafers 8 containing the electrode patterns of the transducers 1, the couplers 3, etc. are arranged on a wafer holder 9 in a chamber 10. The inside of the chamber 10 is exhausted through an exhaustion hole 11 drilled to the substrate of a device and evacuated down to 3 Torrs. Then a high frequency voltage of 3KV is applied between a discharging electrode 12 and the substrate of the device to perform the glow discharge within the chamber 10. In such way, the wafers 8 containing electrodes are cleaned. |
