Abstract:
A microelectromechanical sensor (MEMS) package includes a gyroscope and an accelerometer. The gyroscope is located within a low-pressure cavity that is sealed from an external pressure. The accelerometer is located within a cavity, and the seal for the accelerometer cavity is entirely within the gyroscope cavity. Under normal operating conditions, the accelerometer seal holds the accelerometer cavity at a higher pressure than the pressure of the enclosing gyroscope cavity. In the event that one of the gyroscope seal or the accelerometer seal is broken, the gyroscope senses the change in pressure.
Abstract:
Provided is an inertia sensor that can be reduced in size. An inertia sensor having layers 1a, 2a in which detection parts 20, 30 are formed, the inertial sensor being a laminated structure obtained by laminating two or more of the layers.
Abstract:
For a small sensor produced through a MEMS process, when an electrode pad, wiring, or a shield layer is formed in a final step, it is difficult to nondestructively investigate whether a structure for sensing a physical quantity has been processed satisfactorily. In the present invention, in a physical quantity sensor formed from an MEMS structure, in a structure in which a surface electrode having through wiring is formed on the surface of an electrode substrate and the periphery thereof is insulated, forming a shield layer comprising a metallic material on the surface of the electrode substrate in a planar view and providing a space for internal observation inside the shield layer makes it possible to check for internal defects.
Abstract:
Provided is an MEMS gyroscope, which is resistant against external environmental changes such as a microfabrication process error, a vacuum package process error and a temperature change. The MEMS gyroscope comprises: a frame arranged parallel to a bottom wafer substrate; a sensor mass body excited at one degree of freedom in an excitation mode, and of which the displacement is sensed at two degrees of freedom by Cori-olis force in a sensing mode when an external an-gular velocity is inputted into the frame; and at least two sensing electrodes for sensing the dis-placement of the sensor mass body, the displace-ment being sensed at the two degrees of freedom, wherein the sensor mass body comprises an inner mass body and an outer mass body encompassing the inner mass body, the outer mass body and the frame are connected by a first support spring, and the outer mass body and the inner mass body are connected by a second support spring.
Abstract:
A microelectromechanical gyroscope structure for detecting angular motion about an axis of angular motion. A drive element is suspended for one-dimensional motion in a direction of a drive axis, and a sense body carries one or more sense rotor electrodes and is coupled to the drive element with a first directional spring structure that forces the sense body to move with the drive element and has a preferred direction of motion in a direction of a sense axis. The drive element includes an actuation body and a drive frame wherein the first spring structure couples the sense body directionally to the drive frame, and a second directional spring structure that couples the drive frame to the actuation body and has a preferred direction of motion in the direction of the sense axis.
Abstract:
The invention relates to a MEMS inertial sensor, including a frame to which at least a first seismic body and a second seismic body are connected by resilient means such as to be movable in a suspension plane, transducers to keep the seismic bodies vibrating and determine a movement of the seismic bodies in the suspension plane, and a control unit connected to the transducers by electrical conduction means. The transducers comprise at least one electrode rigidly connected to the first seismic body and one electrode rigidly connected to the second seismic body, the two electrodes being arranged such as to allow direct measurement of the relative movement of the seismic bodies relative to one another in the suspension plane.
Abstract:
A microelectromechanical gyroscope that comprises two seismic masses suspended to form a plane of masses. The seismic masses are excited into rotary oscillation about a common primary axis that is in the plane of masses. Detected angular motion causes a rotary oscillation of the first seismic mass about a first detection axis, and of the second seismic mass about a second detection axis. The detection axes are perpendicular to the plane of masses and separated by a non-zero distance.
Abstract:
A sensing assembly device includes a substrate, a chamber above the substrate, a first piezoelectric gyroscope sensor positioned within the chamber, and a first accelerometer positioned within the chamber.
Abstract:
An acceleration sensor and an angular velocity sensor are sealed in respective pressure atmospheres suitable therefor in the process of a series of bonding steps, thereby improving the detection sensibilities of the sensors. A movable member 111 of an acceleration sensor 11 and a vibrator 121 of an angular velocity sensor 12 are fabricated on the same sensor wafer 10 with a wall 16 interposed therebetween. A cap wafer 20 is formed in which gaps 21, 22 corresponding to the movable member 111 of the acceleration sensor 11 and the vibrator 121 of the angular velocity sensor 12 are provided. Bumps 23 are disposed near the gap 22 of the angular velocity sensor 12. The acceleration sensor 11 is sealed at atmospheric pressure. Then, the angular velocity sensor 12 is subjected to high temperature and a high-load and is vacuum-sealed. Thereafter, cutting with a diamond grindstone and mounting of circuit substrates and a wiring substrate are performed to form a combined sensor.