Inertial test device for MEMS inertial devices

Abstract

The present invention provides an inertia testing device for a micro-electromechanical system device, which includes: a centrifuge, which includes a centrifuge shaft and a centrifuge sample stage, the centrifuge shaft is controlled to rotate; the centrifuge sample stage is fixed to one end of the centrifuge shaft; a three-axis positioning base, which is fixed to the centrifuge sample stage; a test board, which is used to place a reference inertial device and a plurality of micro-electromechanical system inertial devices to be tested, and the test board is detachably fixed to different surfaces of the three-axis positioning base to achieve switching of the motion direction of the inertial device placed on the test board on three axes; a host computer, which is connected to the centrifuge in communication to control the rotation of the centrifuge shaft; the host computer is connected to the test board in communication, and when the centrifuge shaft is controlled to rotate, the reference inertial device and the plurality of micro-electromechanical system inertial devices to be tested output the actual measured acceleration data to the host computer. Compared with the prior art, the present invention can perform high-precision and high-efficiency testing on micro-electromechanical system inertial devices.

Description

[Technical field]

[0001] The invention relates to the technical field of testing micro-electromechanical system devices, and in particular to an inertia testing device for an inertia device of a micro-electromechanical system. [Background technology]

[0002] MEMS devices refer to high-tech electronic mechanical devices with micro-electro-mechanical systems (MEMS) and a size of only a few millimeters or even smaller. Their processing technology integrates lithography, corrosion, thin film, LIGA, silicon micromachining, non-silicon micromachining and precision machining technology. At present, MEMS devices are widely used in a wide range of applications, and common products include MEMS accelerometers, MEMS microphones, MEMS optical sensors, MEMS pressure sensors, MEMS gyroscopes, MEMS humidity sensors, MEMS gas sensors, and MEMS infrared thermopile sensors. For inertial measurement devices (such as three-axis accelerometers and six-axis gyroscopes), a centrifuge can be used to provide the acceleration required by the device, and then some inertial indicators can be tested and analyzed by collecting the measurement data output by the sensor. However, the current test system architecture is generally as follows: the device is placed on a centrifuge, and the inertial data generated when the device moves is transmitted to the host computer for processing using a wireless acquisition module. Although the use of wireless communication can avoid the impact of cable jams on test results to the greatest extent, it has high data latency, slow transmission speed, high bit error rate, and is easily interfered by metal structures of devices such as centrifuges, which significantly reduces the reliability of inertial sensor test results. The inertial indicators obtained by this type of test system cannot provide correct guidance for the research and development and production of MEMS inertial devices, which has a great impact on product quality and yield.

[0003] Therefore, it is urgent to propose a new technical solution to solve the above problems. [Summary of the invention]

[0004] One of the purposes of the present invention is to provide an inertia testing device for a MEMS inertial device, which can perform high-precision and high-efficiency testing on the MEMS inertial device to ensure the reliability of the inertia test data results.

[0005] According to one aspect of the present invention, the present invention provides an inertia testing device for a micro-electromechanical system device, comprising: a centrifuge, comprising a centrifuge shaft and a centrifuge sample stage, wherein the centrifuge shaft is controlled to rotate; the centrifuge sample stage is fixed to one end of the centrifuge shaft and driven to rotate synchronously by the centrifuge shaft; a three-axis positioning base, which is fixed to the centrifuge sample stage; a test board, which is used to place a reference inertial device and a plurality of micro-electromechanical system inertial devices to be tested, wherein the test board is detachably fixed to different surfaces of the three-axis positioning base to achieve switching of the movement direction of the inertial device placed on the test board on three axes; a host computer, which is communicatively connected to the centrifuge to control the rotation of the centrifuge shaft; the host computer is also communicatively connected to the test board, and when the centrifuge shaft is controlled to rotate, the reference inertial device and the plurality of micro-electromechanical system inertial devices to be tested placed on the test board output actually measured acceleration data to the host computer.

[0006] Compared with the prior art, the inertial test device for the MEMS inertial device provided by the present invention is provided with a host computer and a reference inertial device with a predicted characteristic curve. The host computer determines the stability of the currently collected actual measured acceleration data based on the actual measured acceleration data output by the reference inertial device and the predicted characteristic curve of the reference inertial device, and reliably screens the actual measured acceleration data output by the MEMS inertial devices to be tested. In this way, the present invention can perform high-precision and high-efficiency testing on the MEMS inertial device to ensure the reliability of the inertial test data results.

Brief Description of the Drawings

[0007] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0008] Figure 1 It is a structural schematic diagram of an inertia testing device of a micro-electromechanical system inertia device in one embodiment of the present invention;

[0009] Figure 2 In one embodiment of the present invention, Figure 1 The schematic diagram of the relative position relationship between the three-axis positioning base and the PCB test board shown;

[0010] Figure 3 FIG. 4 is a schematic diagram of circuit connections of an inertial testing device for a micro-electromechanical system inertial device in one embodiment of the present invention. [Specific implementation method]

[0011] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0012] The term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments. Unless otherwise specified, the words "connected", "connected", and "connected" herein that indicate electrical connection all refer to direct or indirect electrical connection.

[0013] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore, cannot be understood as limiting the present invention. In the description of the present invention, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0014] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed", "coupled" and the like should be understood in a broad sense; for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0015] In view of the problems existing in the prior art, the present invention provides an inertia testing device for a micro-electromechanical system inertia device. Figure 1 As shown, it is a structural schematic diagram of an inertial testing device of a micro-electromechanical system inertial device in one embodiment of the present invention; please refer to Figure 2 As shown, it is the present invention in one embodiment as Figure 1 The relative position relationship diagram of the three-axis positioning base and the PCB test board is shown in the figure; please refer to Figure 3 As shown, it is a circuit connection diagram of an inertial testing device for a micro-electromechanical system inertial device in one embodiment of the present invention. Figure 1-Figure 3 The inertial testing device of the MEMS inertial device shown includes a centrifuge (not marked), a three-axis positioning base 3 , a PCB (Printed Circuit Board) testing board 4 and a host computer 8 .

[0016] The centrifuge includes a centrifuge shaft 2 and a centrifuge sample table 1. The centrifuge shaft 2 can be controlled to rotate to generate a target acceleration. Reference formula a = (2πn) 2 r, where a is acceleration, n is the rotation speed of the centrifuge shaft 2, and r is the radial distance of the device relative to the axis of the centrifuge shaft 2. The acceleration of each device under test can be calculated by this formula. The centrifuge sample table 1 is fixed to one end of the centrifuge shaft 2 and is driven by the centrifuge shaft 2 to rotate synchronously.

[0017] The three-axis positioning base 3 is detachably fixed on the centrifuge sample table 1 , and the three-axis positioning base 3 is used to fix the PCB test board 4 .

[0018] The PCB test board 4 is used to place the reference inertial device 7 and several MEMS inertial devices 6 to be tested, and the PCB test board 4 is detachably fixed to different surfaces of the three-axis positioning base 3, so as to switch the movement direction of the inertial devices (e.g., the reference inertial device 7 and several MEMS inertial devices 6 to be tested) placed on the PCB test board 4 on three axes (e.g., X-axis, Y-axis and Z-axis). In one embodiment, the PCB test board 4 includes but is not limited to being fixed to the three-axis positioning base 3 by bolts.

[0019] The host computer 8 is connected to the centrifuge in communication to control the rotation of the centrifuge shaft 2. The host computer 8 is also connected to the PCB test board 4 in communication. When the centrifuge shaft 2 is controlled to rotate, the reference inertial device 7 and several MEMS inertial devices 6 to be tested placed on the PCB test board 4 output the actual measured acceleration data to the host computer 8. The reference inertial device 7 predicts the characteristic curve; the host computer 8 determines the stability of the currently collected acceleration data of the MEMS inertial device 6 to be tested based on the actual measured acceleration data output by the reference inertial device 7, thereby realizing reliable screening of the acceleration data of the MEMS inertial device 6 to be tested.

[0020] The PCB test board 4 includes a PCB test top plate 41 and a PCB test bottom plate 42. During implementation, the PCB test top plate 41 and the PCB test bottom plate 42 can be independent PCB plates. The two PCB plates are stacked and fixed together (not limited to bonding, bolting, etc.) to form a PCB test board 4. Preferably, the PCB test top plate 41 and the PCB test bottom plate 42 can be integrated on a PCB test board 4, the TOP layer (i.e., top layer) surface is the PCB test top plate 41, and the Bottom layer (i.e., bottom layer) surface is the PCB test bottom plate 42. Among them, the PCB test bottom plate 42 is used to place a reference inertial device 7 of a known characteristic curve. The reference inertial device 7 is preferably fixedly set at the center of the PCB test bottom plate 42 by welding, and is aligned with the axis of the centrifuge shaft 2. The PCB test top plate 41 is used to place the MEMS (Micro-Electro-Mechanical System) inertial device 6 to be tested. The placement position of the MEMS inertial device 6 to be tested on the PCB test top plate 41 is as close as possible to the vertical center line of the reference inertial device 7. The vertical center line of the reference inertial device 7 is perpendicular to the test board 4, or the vertical center line of the reference inertial device 7 extends along the Z-axis direction (see Figure 2 As shown). The MEMS inertial device 6 to be tested can be welded to a reserved position on the PCB test top plate 41 by welding. Preferably, a fixed Socket (i.e., socket) test carrier 5 is provided on the PCB test top plate 41 to facilitate the loading and unloading of several MEMS inertial devices 6 to be tested, thereby improving the reusability and efficiency of the test system. That is to say, the Scoket test carrier 5 is provided on the PCB test top plate 41, and the Scoket test carrier 5 is used to detachably plug in the MEMS inertial device 6 to be tested. When the MEMS inertial device 6 to be tested is plugged into the Scoket test carrier 5, an electrical connection is established between the MEMS inertial device 6 to be tested and the PCB test board 4. The state in which the MEMS inertial device 6 to be tested is placed in the Scoket test carrier 5 is as follows. Figure 1-3 It is not shown, but this is understood by those skilled in the art and will not be described in detail here.

[0021] Please refer to Figure 2 As shown, the PCB test board 4 is fixed on Figure 1 The scene shown in FIG. 3-B of the three-axis positioning base 3 (i.e., the PCB test board 4 is fixed at a predetermined position on the first surface of the three-axis positioning base 3 and points to the first orientation). At this time, when the centrifuge shaft 2 rotates, the reference inertial device 7 and each MEMS inertial device 6 to be tested inside the socket test carrier 5 can generate acceleration on the X-axis. When the centrifuge shaft 2 rotates counterclockwise, a positive acceleration a is generated on the X-axis. x+(e.g. +1g), on the contrary, when the centrifuge shaft 2 rotates clockwise, a negative acceleration a is generated on the X-axis. x- (e.g. -1g).

[0022] Similarly, when the reference inertial device 7 and each MEMS inertial device 6 to be tested in the socket test carrier 5 need to generate positive and negative acceleration in the Y-axis direction, Figure 2 The PCB test board 4 in the socket test carrier 5 is rotated 90 degrees clockwise (or 90 degrees counterclockwise), and the position of the MEMS inertial device 6 to be tested loaded inside the socket test carrier 5 relative to the center of the 3-B surface can also be correspondingly rotated 90 degrees clockwise (or 90 degrees counterclockwise), that is, the PCB test board 4 is fixed at a predetermined position on the first surface of the three-axis positioning base 3 and points to the second orientation, wherein the angle between the first orientation and the second orientation is 90 degrees or 270 degrees. At this time, when the centrifuge shaft 2 rotates counterclockwise or clockwise, the reference inertial device 7 and each MEMS inertial device 6 to be tested inside the socket test carrier 5 generate a positive acceleration a on the Y axis. y+ or negative acceleration a y- , wherein the X-axis and the Y-axis are perpendicular to each other, and the planes where the X-axis and the Y-axis are located are parallel to the 3-B surface of the three-axis positioning base 3 (i.e., the first surface of the three-axis positioning base 3), and the planes where the X-axis and the Y-axis are located are parallel to the axis of the centrifuge shaft 2.

[0023] When the PCB test board 4 is fixed on Figure 1 When the 3-A surface of the three-axis positioning base 3 is shown, (i.e., the PCB test board 4 is fixed on the second surface of the three-axis positioning base 3), at this time, when the centrifuge shaft 2 rotates counterclockwise or clockwise, the reference inertial device 7 and each MEMS inertial device 6 to be tested inside the socket test carrier 5 can generate a positive acceleration a in the Z axis. Z+ or negative acceleration a Z- The Z axis is perpendicular to the X axis and the Y axis, and is parallel to the 3-A surface of the three-axis positioning base 3 (i.e., the second surface of the three-axis positioning base 3), and is perpendicular to the axis of the centrifuge shaft 2.

[0024] The following is a detailed introduction Figure 1-Figure 3 The working process of the inertial test device of the MEMS inertial device is shown.

[0025] When testing is required, the host computer 8 drives the centrifuge shaft 2 to rotate counterclockwise (clockwise) at a specific speed, and then inputs a positive (negative) acceleration to the MEMS inertial device 6 to be tested and the reference inertial device 7. The MEMS inertial device 6 to be tested and the reference inertial device 7 can output the actual measured acceleration data, and transmit it to the host computer 8 (DAQ device + display) through the inertial quantity output communication interface 43 on the PCB test board 4. In one embodiment, the inertial quantity output communication interface 43 preferably adopts an IIC (Inter-Integrated Circuit, i.e., integrated circuit bus) interface and / or an SPI interface (Serial Peripheral Interface, i.e., serial peripheral interface), which has fast communication speed, high data accuracy, and the system has good measurement response real-time performance.

[0026] Due to the introduction of the reference inertial device 7, the centrifuge shaft 2 switches direction quickly during circumferential rotation, and there is no need to rotate in a clockwise or counterclockwise direction for a long time to provide a stable acceleration reference input for the device to be tested. The host computer 8 can judge the stability of the current data collection situation based on the data characteristic curve of the reference inertial device 7 received by the inertial quantity output communication interface 43, and reliably screen the output data of the MEMS inertial device 6 to be tested, which helps to obtain more reliable indicators (such as sensitivity, linearity, range, etc.). In other words, the host computer 8 judges the stability of the currently collected actual measured acceleration data based on the actual measured acceleration data output by the reference inertial device 7 and the characteristic curve predicted by the reference inertial device 7, and reliably screens the actual measured acceleration data output by the several MEMS inertial devices 6 to be tested.

[0027] On the other hand, based on the reference inertial device 7 with a predicted characteristic curve, the centrifuge shaft 2 eliminates the step of rotating in the same direction for a long time to achieve data stability. The direction is switched in time, which reduces the possibility of cable jamming caused by multiple circular rotations. It also significantly improves the test efficiency of the overall wafer-level MEMS inertial test system. The overall system architecture is relatively simple, the detachable and mating components are highly reusable and easy to maintain, and the test data results are highly accurate. It can provide more powerful guidance for the research and development and production of wafer-level MEMS inertial devices, and significantly improve the quality and yield of products.

[0028] In summary, the present invention provides an inertia testing device for a micro-electromechanical system device, which comprises: a centrifuge, which comprises a centrifuge shaft 2 and a centrifuge sample stage 1, wherein the centrifuge shaft 2 is controlled to rotate; the centrifuge sample stage 1 is fixed to one end of the centrifuge shaft and is driven to rotate synchronously by the centrifuge shaft 2; a three-axis positioning base 3, which is fixed on the centrifuge sample stage 1; a test board 4, which is used to place a reference inertia device 7 and a plurality of micro-electromechanical system inertia devices 6 to be tested, and the test board 4 is detachable. The three-axis positioning base 3 is fixed to different surfaces of the three-axis positioning base 3 to switch the movement direction of the inertial device placed on the test board 4 on the three axes; the host computer 8 is connected to the centrifuge in communication to control the rotation of the centrifuge shaft 2; the host computer 8 is also connected to the test board 4 in communication, and when the centrifuge shaft 2 is controlled to rotate, the reference inertial device 7 and several MEMS inertial devices 6 to be tested placed on the test board 4 output the actual measured acceleration data to the host computer 8. The reference inertial device 7 predicts the characteristic curve; the host computer 8 judges the stability of the actual measured acceleration data currently collected based on the actual measured acceleration data output by the reference inertial device 7 and the characteristic curve predicted by the reference inertial device 7, and reliably screens the actual measured acceleration data output by the MEMS inertial device 6 to be tested. In this way, the present invention can perform high-precision and high-efficiency testing on the MEMS inertial device to ensure the reliability of the inertial test data results.

[0029] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0030] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify and vary the above embodiments within the scope of the present invention.

Claims

1. An inertial testing device for a micro-electromechanical system device, characterized in that: It includes: A centrifuge, comprising a centrifuge shaft and a centrifuge sample table, wherein the centrifuge shaft is controlled to rotate; the centrifuge sample table is fixed to one end of the centrifuge shaft and is driven by the centrifuge shaft to rotate synchronously; A three-axis positioning base, which is fixed on the centrifuge sample stage; A test board, which is used to place a reference inertial device and a plurality of MEMS inertial devices to be tested, wherein the test board is detachably fixed to different surfaces of the three-axis positioning base to achieve switching of the movement direction of the inertial devices placed on the test board on the three axes; A host computer is connected to the centrifuge in communication with the centrifuge to control the rotation of the centrifuge shaft; the host computer is also connected to the test board in communication with the test board, and when the centrifuge shaft is controlled to rotate, the reference inertial device and the plurality of MEMS inertial devices to be tested placed on the test board output actual measured acceleration data to the host computer; The reference inertial device predicts a characteristic curve; the host computer determines the stability of the currently collected acceleration data of the MEMS inertial device to be tested based on the actually measured acceleration data output by the reference inertial device, so as to realize reliable screening of the acceleration data of the MEMS inertial device to be tested.

2. The inertial testing device for a MEMS device according to claim 1, characterized in that: The test board includes a test top board and a test bottom board opposite to the test top board. The test base plate is used to place a reference inertial device, and the reference inertial device is electrically connected to the test board; The test top plate is used for placing a plurality of MEMS inertial components to be tested, and the plurality of MEMS inertial components to be tested are electrically connected to the test plate.

3. The inertial testing device for a MEMS device according to claim 2, characterized in that: The test board is a PCB test board, which includes a PCB test top board and a PCB test bottom board, wherein the PCB test top board and the PCB test bottom board are independent PCB boards, and the two PCB boards are stacked and fixed together to form the PCB test board; or The test board is a PCB test board, which includes a PCB test top board and a PCB test bottom board. The PCB test top board and the PCB test bottom board are integrated on the PCB test board. The top surface of the PCB test board is the PCB test top board, and the bottom surface of the PCB test board is the PCB test bottom board.

4. The inertial testing device for a MEMS device according to claim 2, characterized in that: The reference inertial device is fixed to the center of the test base plate of the test plate and is aligned with the axis of the centrifuge shaft; The plurality of MEMS inertial components to be tested are fixed on the test top plate of the test board, and the plurality of MEMS inertial components to be tested are close to the vertical center line of the reference inertial component.

5. The inertial testing device for a MEMS device according to claim 2, characterized in that: It also includes a test carrier, which is fixed on the test top plate of the test plate. The test carrier is used for detachably inserting the MEMS inertial device to be tested. When the MEMS inertial device to be tested is inserted into the test carrier, the MEMS inertial device to be tested and the test board are electrically connected.

6. The inertial testing device for a MEMS device according to any one of claims 1 to 5, characterized in that: When the test board is fixedly mounted at a predetermined position on the first surface of the three-axis positioning base and points to a first orientation, if the host computer drives the centrifuge shaft to rotate, the reference inertial device and the plurality of MEMS inertial devices to be tested on the test board generate acceleration in the X-axis, and at this time, the reference inertial device and the plurality of MEMS inertial devices to be tested output actual measured X-axis acceleration data; When the test board is fixedly mounted at a predetermined position on the first surface of the three-axis positioning base and points to the second orientation, if the host computer drives the centrifuge shaft to rotate, the reference inertial device and the plurality of MEMS inertial devices to be tested on the test board generate acceleration on the Y axis, and at this time, the reference inertial device and the plurality of MEMS inertial devices to be tested output the actually measured Y axis acceleration data; When the test board is fixedly mounted on the second surface of the three-axis positioning base, if the host computer drives the centrifuge shaft to rotate, the reference inertial device and the plurality of MEMS inertial devices to be tested on the test board generate acceleration in the Z axis, and at this time, the reference inertial device and the plurality of MEMS inertial devices to be tested output the actually measured Z axis acceleration data; Among them, the angle between the first orientation and the second orientation of the first surface is 90 degrees or 270 degrees; the X-axis and the Y-axis are perpendicular to each other, and the plane defined by the X-axis and the Y-axis is parallel to the axis of the centrifuge shaft; the Z-axis is perpendicular to both the X-axis and the Y-axis, and the Z-axis is perpendicular to the axis of the centrifuge shaft.

7. The inertial testing device for a MEMS device according to claim 6, characterized in that: The plane defined by the X-axis and the Y-axis is parallel to the first surface of the three-axis positioning base; The Z axis is parallel to the second surface of the three-axis positioning base.

8. The inertial testing device for a MEMS device according to claim 6, characterized in that: If the host computer drives the centrifuge shaft to rotate clockwise or counterclockwise, the reference inertial device on the test board and the plurality of MEMS inertial devices to be tested generate positive acceleration or negative acceleration in the corresponding axial direction.

9. The inertial testing device for a MEMS device according to claim 1, characterized in that: The test board is connected to the host computer through a communication interface; The reference inertial device and the plurality of MEMS inertial devices to be tested output actual measured acceleration data which are transmitted to the host computer via the communication interface; The communication interface is an integrated circuit bus interface or a serial peripheral interface.

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