To provide a manufacturing method of a piezoelectric vibration piece capable of easily film-forming a desired electrode at a low cost by utilizing a conventional process.
Corrosion resistant films 11 are formed on both main faces of a crystal wafer 10 for which an etching rate in a thickness direction is high and patterned into a preliminary shape including the outer shape of a tuning fork type crystal vibration piece 1 and a margin part enlarged on the outer side of a detection vibration arm 4 and a wafer surface is exposed. Also, a photoresist layer 13 formed on the corrosion resistant film is patterned into a vibration piece outer shape and the part of the corrosion resistant film corresponding to the margin part is exposed. After forming the preliminary shape by through-etching a wafer exposed surface, the wafer surface is exposed by removing the exposed part of the corrosion resistant film, it is etched and the vibration piece outer shape is formed so as to leave a projected line 14 at the center of the thickness direction on a vibration piece side face. After removing the remaining photoresist layer and corrosion resistant film, an electrode film 16 formed on the vibration piece side face is patterned, the surface of a piezoelectric material is exposed to a projected line tip and electrodes 5a and 5b for detection separated in the thickness direction are formed.
TAKAYAMA KATSUMI
KINOSHITA YUSUKE
TAKEUCHI MANABU
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