Piezoelectric vibration member, method of manufacturing the same, and piezoelectric vibrator

A piezoelectric vibration member comprising:

• a vibration substrate having protrusion portions disposed on one surface and the other surface of the vibration substrate in a thickness direction thereof, one surface of the protrusion portion in the thickness direction having four or more sides;
• and
• vibrating electrodes disposed on the protrusion portions,
• wherein at least one side surface of the protrusion portion has two or more crystal planes having different angles of inclination.

A method of manufacturing a piezoelectric vibration member, the method comprising:

• preparing a crystal wafer;
• forming resist patterns on one surface and the other surface of the crystal wafer in a thickness direction of the crystal wafer;
• forming protrusion portions on one surface and the other surface of the crystal wafer in the thickness direction by etching the crystal wafer, one surface of the protrusion portion in the thickness direction having four or more sides;
• removing the resist patterns from the crystal wafer;
• and
• preparing a vibration substrate by re-etching the crystal wafer from which the resist patterns have been removed to allow at least one side surface of the protrusion portion to have two or more crystal planes.

A piezoelectric vibrator comprising:

• a piezoelectric vibration member including a vibration substrate including a vibrating portion and a surrounding portion which is thinner than the vibrating portion, and vibrating electrodes disposed on one surface and the other surface of the vibrating portion in a thickness direction, the vibrating portion including protrusion portions protruding in relation to one surface and the other surface of the surrounding portion in the thickness direction, and at least one side surface of the protrusion portion having two or more crystal planes;
• upper and lower cases accommodating the piezoelectric vibration member therein;
• connection electrodes disposed on an upper surface of the lower case and electrically connected to an electrode part including the vibrating electrodes;
• and
• external electrodes disposed on a lower surface of the lower case and electrically connected to the connection electrodes.