Piezoelectric vibrator having a restriction portion for restricting scattering of a getter material, oscillator, electronic equipment and radio-controlled timepiece
A piezoelectric vibrator includes a base substrate and a lid substrate which are bonded to each other with a cavity formed therebetween; a piezoelectric vibrating reed which has a pair of vibration arm portions extending in parallel and is mounted on the base substrate within the cavity; and a getter material of a metallic film that is formed on the base substrate or the lid substrate so as to be arranged within the cavity and improve a degree of vacuum within the cavity by being heated. A restriction portion, which is arranged in the cavity and restricts a scattering direction of the getter material evaporated by the heating to suppress a scattering amount scattering toward the vibration arm portion, is formed in the base substrate or the lid substrate.
1. A piezoelectric vibrator including:
a base substrate and a lid substrate which are bonded to each other with a cavity formed therebetween;
a piezoelectric vibrating reed which has a pair of vibration arm portions extending in parallel and is mounted on the base substrate within the cavity; and
a getter material of a metallic film that is formed on the base substrate or the lid substrate so as to be arranged within the cavity and improve a degree of vacuum within the cavity by being heated, and
a restriction portion, arranged in the cavity and restricting a scattering direction of the getter material evaporated by the heating to suppress a scattering amount scattering toward the vibration arm portion, the restriction portion being formed in the base substrate or the lid substrate.
2. The piezoelectric vibrator according to claim 1 ,
wherein the restriction portion protrudes from one substrate of the base substrate and the lid substrate toward the other substrate thereof and is formed in one substrate side in the shape of a wall so as to extend along the vibration arm portion in the state of being separated from a side wall of the cavity, and
wherein the getter material is formed in the one substrate side so as to be arranged between the restriction portion and the side wall in a length shorter than that of the restriction portion.
3. The piezoelectric vibrator according to claim 1 ,
wherein the restriction portion protrudes from one substrate of the base substrate and the lid substrate toward the other substrate thereof, and is formed in the one substrate side so as to extend along the vibration arm portion, and
wherein the getter material is formed on the restriction portion or on the other substrate in the state of being accommodated in a gap between the restriction portion and the other substrate facing each other.
4. An oscillator in which the piezoelectric vibrator according to claim 1 is electrically connected to an integrated circuit as an oscillating element.
5. Electronic equipment in which the piezoelectric vibrator according to claim 1 is electrically connected to a measurement portion.
6. A radio-controlled timepiece in which the piezoelectric vibrator according to claim 1 is electrically connected to a filter portion.