Patent ID: 7553609

Claim:
A method of manufacturing a piezoelectric vibrating piece having one pair of vibrating arm parts having been disposed parallel by using a photolithography technique to a piezoelectric plate consisting of a piezoelectric material, a base part integrally fixing base end sides of the one pair of vibrating arm parts, groove parts having been formed respectively in both main faces of the one pair of vibrating arm parts along a longitudinal direction of the vibrating arm part, and an exciting electrode which is formed on outer surfaces of the one pair of vibrating arm parts and which vibrates the one pair of vibrating arm parts, characterized in that an electrode formation process for forming the exciting electrode has: a coating process for coating an electrically conductive film to whole outer surfaces of the one pair of vibrating arm parts, an application process for applying a photosensitive film consisting of positive type photosensitive material onto the electrically conductive film, an exposure process in which a mask having an opening part having been previously patterned is disposed such that the opening part is located on at least either edge of a 1st edge, in two places, formed by the main face and a side face of the vibrating arm part or a 2nd edge, in two places, formed by the main face and a side face of the groove part, and a parallel light is slantingly irradiated through the opening part toward at least either of a bottom face or an outside of the groove part while following a face intersecting perpendicularly to a longitudinal direction of the vibrating arm part to thereby expose the photosensitive film, a development process for developing the photosensitive film to thereby remove an exposed region, and an etching process for etching-working the electrically conductive film with the residual photosensitive film being made a mask, thereby forming the exciting electrode.