MANUFACTURE OF ACOUSTIC LENS

摘要

PURPOSE:To accurately position a lens part and an outer peripheral part and to eliminate the deformation and roughening of the lens part by positioning the etching place of the lens part and the etching place of the outer peripheral part by using a common photomask. CONSTITUTION:Insulating films 2 and 3 and negative resist 4 are formed on a substrate 1 and photolithography technics is applied to form opening parts 5 and 6 at the same time. Then the opening 5 is covered with photoresist 7 and then the area of the opening 6 is etched twice to remove the films 3 and 2 in order. Then the resist 7 is removed and the film 3 in the opening 5 is etched. Then etching for forming the outer peripheral part is carried out. Further, the film 2 which covers the opening 5 is removed and etching is performed to form a spherical concave surface part 9 which is the lens part.