Sensor element, sensor device, and electronic apparatus
View Patent ↗A sensor element includes a base part, a detection vibrating arm extended from the base part, and detection parts that are provided on the detection vibrating arm and detect flexural vibration of the detection vibrating arm, the detection parts each have a first electrode layer, a second electrode layer provided at an opposite side to the detection vibrating arm with respect to the first electrode layer, and a piezoelectric layer provided between the first electrode layer and the second electrode layer, and the detection parts have parts provided over boundary parts between the detection vibrating arm and the base part and the parts bend or curve to extend in a direction including a direction component orthogonal to an extension direction of the detection vibrating arm along side surfaces of the detection vibrating arm and the base part.
1. A sensor element comprising:
a base part;
a vibrating arm extended from the base part; and
a detection part that is provided above the vibrating arm and the base part and detects flexural vibration of the vibrating arm, wherein
the detection part has a first electrode layer, a second electrode layer, and a piezoelectric layer provided between the first electrode layer and the second electrode and layer,
the detection part bends or curves to extend in a direction including a direction component orthogonal to an extension direction of the vibrating arm along side surfaces of the vibrating arm and the base part,
an end of the detection part at the base part side is located at an outer side of the vibrating arm than a virtual surface formed by extending the side surface of the vibrating arm along the extension direction of the vibrating arm, and
when a width of the vibrating arm is Ws and a distance between the virtual surface and the end of the detection part at the base part side is Ls, Ls/Ws is equal to or less than 1.2.
2. The sensor element according to claim 1 , wherein the detection part is provided so that a distance between the detection tart and the side surfaces of the vibrating arm and the base part constant.
3. The sensor element according to claim 1 , further comprising:
a detection vibrating arm forming the vibrating arm;
a drive vibrating arm extended from the base part; and
a drive part that is provided above the drive vibrating arm and flexurally vibrates the drive vibrating arm.
4. The sensor element according to claim 3 , wherein the drive part has a piezoelectric element that expands and contracts in an extension direction of the drive vibrating arm, and
the drive part is provided above the drive vibrating arm and the base part, and bends or curves to extend in a direction including a direction component orthogonal to the extension direction of the drive vibrating arm along side surfaces of the drive vibrating arm and the base part.
5. The sensor element according to claim 3 , wherein the base part has a main body part, and a pair of connecting arms extended from the main body part in opposite directions,
the drive vibrating arm is extended from each of the connecting arms in a direction crossing an extension direction of each of the connecting arms, and
the detection vibrating arm is extended from the main body part in a direction crossing the extension direction of each of the connecting arms.
6. A sensor device comprising the sensor element according to claim 1 .
7. A sensor device comprising the sensor element according to claim 2 .
8. A sensor device comprising the sensor element according to claim 3 .
9. A sensor device comprising the sensor element according to claim 4 .
10. A sensor device comprising the sensor element according to claim 5 .
11. An electronic apparatus comprising the sensor element according to claim 1 .
12. An electronic apparatus comprising the sensor element according to claim 2 .
13. An electronic apparatus comprising the sensor element according to claim 3 .
14. An electronic apparatus comprising the sensor element according to claim 4 .