Abstract: An example microelectromechanical system (MEMS) force sensor is described herein. The MEMS force sensor can include a sensor die configured to receive an applied force. The sensor die can include a first substrate and a second substrate, where a cavity is formed in the first substrate, and where at least a portion of the second substrate defines a deformable membrane. The MEMS force sensor can also include an etch stop layer arranged between the first substrate and the second substrate, and a sensing element arranged on a surface of the second substrate. The sensing element can be configured to convert a strain on the surface of the membrane substrate to an analog electrical signal that is proportional to the strain.

Abstract: Described herein is a sensor in chip scale package form factor. For example, a non-vacuum packaged sensor chip described herein includes a substrate, and a sensing element arranged on the substrate. The sensing element is configured to change resistance with temperature. Additionally, the non-vacuum packaged sensor chip includes an absorbing layer configured to absorb middle infrared (“MIR”) radiation.

Abstract: Described herein is a ruggedized microelectromechanical (“MEMS”) force sensor. The sensor employs piezoresistive or piezoelectric sensing elements for force sensing where the force is converted to strain and converted to electrical signal. In one aspect, both the piezoresistive and the piezoelectric sensing elements are formed on one substrate and later bonded to another substrate on which the integrated circuitry is formed. In another aspect, the piezoelectric sensing element is formed on one substrate and later bonded to another substrate on which both the piezoresistive sensing element and the integrated circuitry are formed.

Abstract: Integrated systems for force or strain sensing and haptic feedback are described herein. An example force-haptic system can include a sensor chip configured to receive an applied force, where the sensor chip includes at least one sensing element and an integrated circuit. The force-haptic system can also include a haptic actuator configured to convert an electrical excitation signal into mechanical vibration. Further, the force-haptic system can include a circuit board, where the sensor chip and the haptic actuator are electrically and mechanically coupled to the circuit board. The integrated circuit can be configured to process an electrical signal received from the at least one sensing element and to output the electrical excitation signal.

Abstract: MEMS force sensors for providing temperature coefficient of offset (TCO) compensation are described herein. An example MEMS force sensor can include a TCO compensation layer to minimize the TCO of the force sensor. The bottom side of the force sensor can be electrically and mechanically mounted on a package substrate while the TCO compensation layer is disposed on the top side of the sensor. It is shown the TCO can be reduced to zero with the appropriate combination of Young's modulus, thickness, and/or thermal coefficient of expansion (TCE) of the TCO compensation layer.

Abstract: Described herein is a method and system for testing a force or strain sensor in a continuous fashion. The method employs a sensor, a test fixture, a load cell, a mechanical actuator and tester hardware and software to simultaneously record signal outputs from the sensor and load cell as functions of time. The method provides time synchronization events for recording data streams between, for example, a linear ramp of the force on, or displacement of, the sensor and for extracting performance characteristics from the data in post-test processing.

Abstract: Described herein is a force attenuator for a force sensor. The force attenuator can linearly attenuate the force applied on the force sensor and therefore significantly extend the maximum sensing range of the force sensor. The area ratio of the force attenuator to the force sensor determines the maximum load available in a linear fashion.

Abstract: Described herein is a MEMS force sensor with stress concentration design. The stress concentration can be performed by providing slots, whether through or blind, and/or selective thinning of the substrate. The MEMS force sensor is in chip scale package with solder bumps or metal pillars and there are sensing elements formed on the sensor substrate at the stress concentrate area. The stress concentration can be realized through slots, selective thinning and a combination of both.

Abstract: MEMS force sensors for providing temperature coefficient of offset (TCO) compensation are described herein. An example MEMS force sensor can include a TCO compensation layer to minimize the TCO of the force sensor. The bottom side of the force sensor can be electrically and mechanically mounted on a package substrate while the TCO compensation layer is disposed on the top side of the sensor. It is shown the TCO can be reduced to zero with the appropriate combination of Young's modulus, thickness, and/or thermal coefficient of expansion (TCE) of the TCO compensation layer.

Abstract: An example microelectromechanical system (MEMS) force sensor is described herein. The MEMS force sensor can include a sensor die configured to receive an applied force. The sensor die can include a first substrate and a second substrate, where a cavity is formed in the first substrate, and where at least a portion of the second substrate defines a deformable membrane. The MEMS force sensor can also include an etch stop layer arranged between the first substrate and the second substrate, and a sensing element arranged on a surface of the second substrate. The sensing element can be configured to convert a strain on the surface of the membrane substrate to an analog electrical signal that is proportional to the strain.

Abstract: In one embodiment, a ruggedized wafer level microelectromechanical (“MEMS”) force sensor includes a base and a cap. The MEMS force sensor includes a flexible membrane and a sensing element. The sensing element is electrically connected to integrated complementary metal-oxide-semiconductor (“CMOS”) circuitry provided on the same substrate as the sensing element. The CMOS circuitry can be configured to amplify, digitize, calibrate, store, and/or communicate force values through electrical terminals to external circuitry.

Abstract: Described herein is a ruggedized microelectromechanical (“MEMS”) force sensor including both piezoresistive and piezoelectric sensing elements and integrated with complementary metal-oxide-semiconductor (“CMOS”) circuitry on the same chip. The sensor employs piezoresistive strain gauges for static force and piezoelectric strain gauges for dynamic changes in force. Both piezoresistive and piezoelectric sensing elements are electrically connected to integrated circuits provided on the same substrate as the sensing elements. The integrated circuits can be configured to amplify, digitize, calibrate, store, and/or communicate force values electrical terminals to external circuitry.

Abstract: Described herein is a ruggedized microelectromechanical (“MEMS”) force sensor. The sensor employs piezoresistive or piezoelectric sensing elements for force sensing where the force is converted to strain and converted to electrical signal. In one aspect, both the piezoresistive and the piezoelectric sensing elements are formed on one substrate and later bonded to another substrate on which the integrated circuitry is formed. In another aspect, the piezoelectric sensing element is formed on one substrate and later bonded to another substrate on which both the piezoresistive sensing element and the integrated circuitry are formed.

Abstract: Described herein is a ruggedized microelectromechanical (“MEMS”) force sensor including a sensor die and a strain transfer layer. The MEMS force sensor employs piezoresistive or piezoelectric strain gauges for strain sensing where the strain is transferred through the strain transfer layer, which is disposed on the top or bottom side of the sensor die. In the case of the top side strain transfer layer, the MEMS force sensor includes mechanical anchors. In the case of the bottom side strain transfer layer, the protection layer is added on the top side of the sensor die for bond wire protection.

Abstract: Described herein is a MEMS force sensor with stress concentration design. The stress concentration can be performed by providing slots, whether through or blind, and/or selective thinning of the substrate. The MEMS force sensor is in chip scale package with solder bumps or metal pillars and there are sensing elements formed on the sensor substrate at the stress concentrate area. The stress concentration can be realized through slots, selective thinning and a combination of both.

Abstract: An example force sensitive touch panel device can include a device body; a touch surface for receiving a touch force; a sensor for sensing touch force that is arranged between the device body and the touch surface; and a membrane configured to mechanically isolate the device body and the touch surface. Additionally, the membrane can apply a preload force to the sensor.

Abstract: A multi-dimensional track pad is described that acts as human-machine interface (HMI). Inputs to the HMI can be made not only using the tradition two-dimensional (X-Y) inputs of a track pad, but also a third dimension, force, and even a fourth dimension, time. Tactile or audible feedback to the inputs can be provided. Methods of using the HMI to control a system are described as well as a track pad system that utilizes the HMI in communication with a processor.

Abstract: An example force-sensitive electronic device is described herein. The device can include a device body, a touch surface bonded to the device body in a bonded region that is arranged along a peripheral edge of the touch surface, and a plurality of force sensors that are arranged between the device body and the touch surface. Each of the plurality of force sensors can be spaced apart from the bonded region.

Abstract: An example MEMS force sensor is described herein. The MEMS force sensor can include a cap for receiving an applied force and a sensor bonded to the cap. A trench and a cavity can be formed in the sensor. The trench can be formed along at least a portion of a peripheral edge of the sensor. The cavity can define an outer wall and a flexible sensing element, and the outer wall can be arranged between the trench and the cavity. The cavity can be sealed between the cap and the sensor. The sensor can also include a sensor element formed on the flexible sensing element. The sensor element can change an electrical characteristic in response to deflection of the flexible sensing element.

Abstract: An example actuator device for a force sensor is described herein. The device can include a device body, a force concentrator element, an overload protection element, one or more legs, and an attachment layer for attaching the device to a substrate. An example method for assembling a force sensing system is also described herein. Further, an example method for protecting a force sensor from excessive forces or displacement is described herein.