| 摘要 |
PURPOSE:To stabilize quality and also to improve a yield by eliminating variance in shape of an electrode to be formed by using a mask provided with a pattern opening part with its side wall formed slanting and expanding out toward its surface. CONSTITUTION:Side wall 8 of pattern opening part 7 of mask 4 is formed slanting and expanding out toward opening part 12 of surface 5 touching substrate 1 and the width of opening part 12 is greater than that of opening part 11. With mask 4 like this arranged on substrate 1, aluminum is vapor-deposited as shown by an arrow to form aluminum vapor-deposition layers 13 and 14 on mask 4 and substrate 1, unneeded vapor-deposition layer 13 is removed by removing mask 4 to form fixed electrode 14 on substrate 1, and a sound absorbing layer is formed at a fixed position to complete a surface-wave filter. In the above-mentioned constitution, the flank of electrode 14 is perpendicular to substrate 1 and flat and its electode shape never varies, so that characteristics will not deteriorate. |
