| 摘要 |
PURPOSE:To raise pattern accuracy, by using a solder resist as an acoustic absorption film, and forming a pattern by a photoetching technique. CONSTITUTION:An acoustic absorption film provided with high position accuracy and pattern accuracy is obtained by forming an electrode pattern group consisting of an input transducer 1, an output transducer 4, a multistrip coupler 3, etc., on a piezoelectric crystal substrate by use of photoetching technique, and after that, applying a solder resist by scores of mum in thickness by use of the screen printing method, sensitizing acoustic absorption film patterns 7, 8 and 9 by the projection exposure method or the adhesion exposure method, and after that, melting and removing the solder resist except the acoustic absorption film pattern by the developing operation. |
