CN-121994396-A - Multidimensional force sensor and packaging method thereof

CN121994396ACN 121994396 ACN121994396 ACN 121994396ACN-121994396-A

Abstract

The application provides a multidimensional force sensor and a packaging method thereof, the multi-dimensional force sensor is formed by assembling a packaging assembly, a multi-dimensional force sensor chip and a special signal conditioning circuit board. The packaging assembly comprises a base, an elastomer and a flange, wherein the multidimensional force sensor chip is arranged on an assembly boss of the base, a first limit part is arranged on the assembly boss and is matched with a second limit part on the multidimensional force sensor chip, primary alignment of the multidimensional force sensor chip and the packaging assembly is achieved, the bottom of the aligned multidimensional force sensor chip is connected with the assembly boss of the base, fixation of the multidimensional force sensor chip is achieved, the elastomer comprises a force attenuation structure and a force transmission column, the force transmission column is arranged on the surface of the force attenuation structure facing the multidimensional force sensor chip, the force transmission column is used for transmitting force and/or moment reduced in an equal proportion by the force attenuation structure to the multidimensional force sensor chip, and the flange is assembled on one surface of the elastomer facing away from the base and is used for receiving external load and transmitting the external load to the elastomer.

Inventors

ZHAO YUEJIN

Assignees

北京傲粒微电子有限公司

Dates

Publication Date: 20260508
Application Date: 20260106

Claims (9)

1. The multi-dimensional force sensor is characterized by being assembled by a multi-dimensional force sensor chip, a special signal conditioning circuit board and a packaging assembly, wherein the packaging assembly comprises a base, an elastomer and a flange, and the multi-dimensional force sensor chip comprises a silicon-based piezoresistive or capacitive micro-electromechanical system ‌ MEMS multi-dimensional force sensor chip, a metal-based strain multi-dimensional force sensor chip and a multi-dimensional force sensor chip prepared on a compound semiconductor substrate; The multi-dimensional force sensor comprises a base, a multi-dimensional force sensor chip, an elastic body, a base, a first limiting part, a second limiting part, a first connecting part and a second connecting part, wherein the upper surface of the base is provided with an assembling boss which is provided with the first limiting part, the assembling boss is used for being matched and connected with the bottom surface of the multi-dimensional force sensor chip, the first limiting part is used for being matched with the second limiting part of the multi-dimensional force sensor chip so as to limit the position of the multi-dimensional force sensor chip on the assembling boss and ensure that the multi-dimensional force sensor chip is aligned with the elastic body and the center of the base in the packaging assembly; the elastic body is assembled on one surface of the base, provided with the assembling boss, the elastic body comprises a force attenuation structure and a force transmission column, the force transmission column is arranged in the center of the surface of the force attenuation structure, facing the multidimensional force sensor chip, the force transmission column is used for transmitting force and/or moment which are reduced in an equal proportion by the force attenuation structure to the multidimensional force sensor chip, and the flange is assembled on one surface of the elastic body, facing away from the base.
2. The multi-dimensional force sensor of claim 1, wherein the first spacing portion is a spacing protrusion and/or a spacing groove that mates with a second spacing portion of a multi-dimensional force sensor chip.
3. The multi-dimensional force sensor of claim 1, wherein the force attenuating structure comprises an edge strut portion, a deformation beam portion, and a central force bearing stage; the center stress carrying platform is positioned at the center of the force attenuation structure, is connected with the force transmission column, is provided with a screw hole connected with the flange, and is used for receiving the load from the flange and transmitting the load to the deformation beam part; The deformation beam part is connected between the center stress carrier and the edge clamped part and comprises a plurality of symmetrically arranged deformation beams, the deformation beam part receives the load from the center stress carrier, attenuates and physically decouples the load through the flexible deformation of the deformation beam, and transmits the force after the attenuation and object understanding coupling to the force transmission column; the edge fixing portion is provided with a screw hole connected with the base and used for restraining the deformation beam portion when the base is fixed.
4. A multi-dimensional force sensor according to claim 3, wherein each of said deformed beams comprises a first end portion connected to said central force-bearing stage and a second end portion connected to said edge-clamped portion; The deformation beam part is arranged in a central symmetry way by taking the central stress carrier as the center, and is used for generating flexible deformation in different directions or types under different external loads so as to improve force measurement sensitivity and reduce force crosstalk between different dimensions.
5. The multi-dimensional force sensor of claim 1, wherein the multi-dimensional force sensor chip comprises a chip middle stress body, a frame positioned on the outer ring of the chip, and a chip strain body connecting the chip middle stress body and the frame, wherein a plurality of groups of sensitive elements are arranged on the chip strain body, and each group of sensitive elements is used for sensing force and/or moment of one dimension; the multidimensional force sensor chip is provided with a second limiting part towards the bottom surface of the assembling boss, and the first limiting part and the second limiting part are mutually matched to limit the position of the multidimensional force sensor chip on the assembling boss; the force transmission column of the elastic body is fixedly connected to the chip middle stress body of the multi-dimensional force sensor chip.
6. A method of packaging a multi-dimensional force sensor according to any one of claims 1 to 5, comprising: Bonding a multi-dimensional force sensor chip over an assembly boss of a base to maintain alignment of the multi-dimensional force sensor chip with a package assembly; The elastic body is assembled on one surface of the base, provided with the assembling boss, through a screw hole of the edge fixing part of the elastic body so as to realize fixed support of the elastic body, wherein a force transmission column in the elastic body is connected to a chip middle stress body of the multi-dimensional force sensor chip so as to realize connection of the elastic body and the multi-dimensional force sensor chip; The flange is assembled on one surface of the elastic body, which is opposite to the base, through the screw hole of the center stress carrying platform of the elastic body, so that the connection between the flange and the elastic body is realized.
7. The method of packaging of claim 6, wherein bonding the multi-dimensional force sensor die over the mounting boss of the submount comprises: Performing secondary alignment on the multi-dimensional force sensor chip and the assembling boss, wherein the primary alignment comprises alignment matching of the first limit part and the second limit part; And connecting the aligned multidimensional force sensor chip with the assembling boss through at least one mode of an adhesion technology, a glass micro-fusion technology and a eutectic bonding technology.
8. The packaging method according to claim 6, wherein the fitting of the elastic body to the face of the base provided with the fitting boss through the screw hole at the edge-clamped portion of the elastic body comprises: the edge clamped part and the base are connected through the screw holes of the edge clamped part of the elastic body, and meanwhile, the chip middle stress body of the multidimensional force sensor chip is connected with the force transmission column through at least one mode of an adhesion technology, a glass micro-fusion technology and a eutectic bonding technology to form an integrated assembly structure.
9. The packaging method of claim 6, further comprising: The special signal conditioning circuit board is assembled in an empty space surrounded by the base and the elastic body, wherein the special signal conditioning circuit board is used for conditioning signals of the multi-dimensional force sensor chip, and the signal conditioning comprises multi-channel acquisition, filtering, amplifying, analog-to-digital conversion, temperature compensation, decoupling and digital signal output; and electrically connecting the multidimensional force sensor chip with the special signal conditioning circuit board.

Description

Multidimensional force sensor and packaging method thereof Technical Field The application relates to the technical field of sensors, in particular to a multi-dimensional force sensor and a packaging method thereof. Background The multidimensional force sensor is a device capable of measuring forces and/or moments in multiple directions simultaneously, and has wide application in the fields of robots, intelligent manufacturing, precise detection and the like. High-precision force feedback plays a critical role in intelligent collaborative operations such as robots and the like, and is a key for ensuring high-efficiency and high-precision force control operations. Currently, the mainstream technology is a strain gauge type force sensor, wherein a metal deformation body is prepared by a mechanical processing mode, a plurality of resistance strain gauges are manually stuck on the deformation body by using a special adhesive, and an external board-level circuit is mounted. When external force is applied to the sensor, the deformation body is flexibly deformed, and as the strain gauge is firmly adhered to the deformation body, the strain gauge generates deformation identical to the deformation body, so that the resistance value of the metal or semiconductor strain gauge is changed. Typically, four resistive strain gages are used to form a wheatstone bridge, the resulting differential output voltage signal is used to measure force in one dimension, and the applied multidimensional force and/or moment can be measured by pasting multiple wheatstone bridges of multiple sets of resistive strain gages. The strain gauge type multidimensional force sensor is a mechanical force sensor, has the advantages of higher reliability, large volume, high cost, slow response speed and large range lower limit, and is not suitable for high-precision, small load, high response speed and microminiaturization application. Meanwhile, as the strain gauge force sensor mostly needs to be manually pasted with the strain gauge, the strain gauge force sensor is affected by factors such as adhesive property, pasting position and the like, the accuracy is low, and a complex calibration process is needed to reduce errors subsequently. Microelectromechanical systems (Micro-Electro-MECHANICAL SYSTEMS, ‌ MEMS) force sensors are an emerging technology route, gradually exhibiting great application potential in the robot field, with piezoresistive MEMS multidimensional force sensors being most widely used. The piezoresistive MEMS multidimensional force sensor works based on the piezoresistive effect of silicon, and a multidimensional force sensor chip is prepared through a micro-nano processing technology. The multidimensional force sensor chip is composed of a strain body, a sensitive element and a stress body. When external force acts on the stressed body part, the strained body deforms, and the sensing element converts the force and/or moment into a measurable electrical signal to be output through sensing the deformation amount of the strained body. The existing MEMS force sensor has the advantages of high precision, high response speed, small volume, low power consumption and the like, but has a plurality of limitations in application, such as small measuring range, limited overload resistance and difficult dimension lifting, and particularly limits the direct application of the MEMS force sensor in equipment such as loading robots above 10N (newton). In the related art, the package design of the multidimensional force sensor is often independent of the chip design of the multidimensional force sensor, the package component cannot effectively cooperate with the symmetry and mechanical characteristics of the chip, and the sensitivity and the inter-dimensional coupling become the constraints on the overall performance of the multidimensional force sensor. The related packaging scheme is difficult to realize the optimal structural integration and performance exertion of the multidimensional force sensor, and a packaging assembly capable of improving the assembly precision and optimizing the force transmission efficiency is needed. Disclosure of Invention The embodiment of the application provides a multi-dimensional force sensor and a packaging method thereof, which can improve the assembly precision and the force transmission efficiency of the multi-dimensional force sensor and reduce inter-dimensional coupling and environmental interference. The technical scheme of the embodiment of the application comprises the following steps: The embodiment of the application provides a multi-dimensional force sensor, which is formed by assembling a multi-dimensional force sensor chip, a special signal conditioning circuit board and a packaging assembly, wherein the packaging assembly comprises a base, an elastomer and a flange, the multi-dimensional force sensor chip comprises a silicon-based piezoresistive or capacitive MEMS multi-dimensional force sensor chi