Method for manufacturing a piezoelectric resonator

A method for manufacturing a crystal piezoelectric resonator including a crystal resonator element having a plate-like base and two arms extending substantially parallel to one another and substantially perpendicular to the base, the method comprising:

• irradiating a first surface of the arms with F2 excimer laser light;
• irradiating a second surface of the arms with F2 excimer laser light, the second surface being formed on an opposite side of the arms from the first surface;
• removing a region irradiated with the F2 excimer laser light to form a first groove in the first surface, the first groove having a predetermined cross sectional shape perpendicular to a longitudinal direction of the first groove and including a length extending along a length of each arm and a width extending along a width of each arm, the length of each first groove extending substantially parallel to a first groove of an adjacent arm and substantially perpendicular to the base;
• and
• removing a region irradiated with the F2 excimer laser light to form a second groove in the second surface having a length extending along a length of each arm and a width extending along a width of each arm, the length of each second groove extending substantially parallel to a second groove of an adjacent arm, substantially parallel to the first groove, and substantially perpendicular to the base, the second groove having a predetermined cross sectional shape perpendicular to a longitudinal direction of the second groove and cooperating with the first groove to provide each arm with a substantially H-shaped cross section, the second groove being formed on an opposite side of the arms from the first groove and being coaxially aligned with the first groove.