CN1282598C - Dynamic test loading device for MEMS wafer or device - Google Patents

Abstract

The invention discloses a dynamic test loading device for MEMS wafers or devices. The structure of the device is as follows: a light-transmitting sheet is placed on the opening end surface of a cavity to form a sealed cavity with the cavity, and electrodes are installed on the cavity. There are air charging port, vacuum port and vacuum gauge port, the bracket is fixed on the base of the cavity, the adjusting screw is installed in the base of the bracket, the piezoelectric ceramic is placed in the bracket, the lower end is connected with the adjusting screw, and the upper end is connected with the bracket Then, the support plate is fixed on the bracket, and the disc bead is fixed with the support plate. The device can obtain precise vibration frequency and amplitude through piezoelectric ceramics, and can change the frequency and amplitude in a relatively large range, and is easy to control. It can provide different vacuum degrees for MEMS wafer or device testing. temperature and different vibration state environments.

Description

Dynamic test loading device for MEMS wafer or device

technical field

The invention relates to a loading device, in particular to a loading device applied to the dynamic testing of MEMS (Micro-electromechanical systems, micro-electromechanical systems) wafers or devices.

Background technique

The loading device for the dynamic test of the specimen, that is, the vibrator is a device that converts electrical energy into mechanical energy and provides vibration to the specimen. In recent years, a large number of MEMS devices have appeared and been applied. In order to obtain the modal parameters, it is necessary to load them with excitation and measure their responses. Traditional vibration exciters have been widely used in vibration loading tests of aircraft, missiles, ships, machine tools, bridges, etc., and have also been applied to local components that need to provide vibration and other forms of loading for testing. The disadvantages of traditional loading devices are: ①The application of these loading devices generally requires the sensor to be installed on the specimen, so the specimen needs to have a large enough size, and it is also necessary to ensure that the installation of the sensor is not enough to affect the dynamic test of the specimen Accuracy, the accuracy of the vibration and measurement system provided by these loading devices is not suitable for dynamic testing of tiny specimens, so it is not suitable for small specimens such as MEMS wafers or devices. ②The traditional excitation loading test is carried out in the atmospheric environment or even the harsh working environment, which is not suitable for dynamic testing of MEMS wafers or devices and other specimens with strict environmental requirements.

Contents of the invention

The object of the present invention is to overcome the disadvantages of the above-mentioned prior art, and provide a dynamic test loading device for MEMS wafers or devices. The device can provide different vacuum degrees, different temperatures and different vibration state environments for dynamic testing of MEMS wafers or devices.

In order to achieve the above object, the technical solution adopted by the present invention is: a dynamic test loading device for MEMS wafers or devices, including a light-transmitting sheet, a cavity, a bracket and a support plate, and the light-transmitting sheet is placed on the opening end face of the cavity , forming a sealed cavity with the cavity, electrodes are installed on the cavity, and there are gas charging port, vacuum port and vacuum gauge interface, the bracket is fixed on the base of the cavity, the adjusting screw is installed in the base of the bracket, and the piezoelectric ceramic device In the bracket, its lower end is connected with the adjustment screw, its upper end is connected with the bracket, the supporting plate is fixed on the bracket, and the disc bead is fixed with the supporting plate.

Compared with the prior art, the present invention has the following advantages:

(1) Dynamic tests can be carried out under different pressures and temperatures, thus providing necessary data for accurately obtaining the modal parameters of MEMS wafers or devices.

(2) Accurate vibration frequency and amplitude can be obtained through piezoelectric ceramics, and the frequency and amplitude can be changed in a relatively large range, and it is easy to control.

(3) The required vacuum degree can be obtained through the vacuum system.

(4) When the temperature of the MEMS wafer or device needs to be controlled, the precise temperature of the test piece can be obtained through the heating plate, so that the MEMS wafer or device can obtain different temperatures.

Description of drawings

Figure 1 is a front sectional view of an embodiment of the present invention.

Fig. 2 is a left sectional view of the embodiment in Fig. 1 .

Detailed ways

As shown in Figures 1 and 2, a dynamic test loading device for a MEMS wafer or device includes a light-transmitting sheet 9, a cavity 1, a bracket 5 and a support plate 13, and the opening end surface of the light-transmitting sheet 9 and the cavity 1 A sealing ring 7 is interposed, and is connected to the flange 16 through the sealing ring 8. The flange 16 is fixed to the opening end face of the vacuum cavity 1 through bolts 17 and nuts 18. The light-transmitting sheet 9 and the cavity 1 form a sealed cavity. Provides an airtight environment for dynamic testing of MEMS wafers or devices.

An electrode 21 is installed on the cavity 1, and an air charging port 6, a vacuum port 20 and a vacuum gauge interface 22 are opened. The bracket 5 can be fixed on the base of the cavity 1 by bolts 2, and the adjusting screw 3 is installed in the base of the bracket 5. , the piezoelectric ceramic (PZT) 4 is placed in the bracket 5, the lower end of the piezoelectric ceramic 4 is connected to the adjusting screw 3, and the upper end of the piezoelectric ceramic 4 is connected to the bracket 5 by adjusting the adjusting screw 3, and the supporting plate 13 is passed through the screw 12 is fixed on the bracket 5, and the wafer bead 14 is used to press the MEMS wafer or device 10. When the temperature of the MEMS wafer or device 10 needs to be controlled, a heating device can be placed between the wafer bead 14 and the support plate 13. The plate 11 and the disc bead 14 are fixed on the heating plate 11 by bolts 15 , and the heating plate 11 is fixed on the support plate 13 by bolts 19 . The heating plate 11 can be heated by means of resistance wire, etc., and the wires of the heating plate 11 are connected to the external power line through the electrodes 21 .

The electric wires of the piezoelectric ceramic 4 are connected to the external power line through the electrodes 21 , and the vacuum gauge is inserted into the vacuum gauge interface 22 to measure the vacuum degree in the vacuum cavity 1 .

When carrying out the dynamic test of the MEMS wafer or device 10 , it is clamped on the heating plate 11 and pressed by the wafer pressure bar 14 . The loading process of the MEMS wafer or device 10 includes pressurization, heating and vibration.

Connect the loading device with a vacuum pump or high-pressure nitrogen to achieve a vacuum or nitrogen-filled environment. The vacuum port 20 is connected with a vacuum pump, and the vacuum pump pumps the environment in the cavity 1 to a required vacuum through the vacuum port 20 . The charging port 6 is connected with high-pressure nitrogen. If nitrogen environment is required, the high-pressure nitrogen can be adjusted through the charging valve, and injected into the vacuum chamber 1 through the charging port 6 according to the predetermined nitrogen pressure, so that dynamic testing of devices under different pressure environments can be realized.

The MEMS wafer or device 10 is in contact with the heating plate 11 and heated by the heating plate 11 to realize dynamic testing at different temperatures. The computer can control the voltage applied to the heating plate 11 to realize heating, and its temperature is adjustable and controllable to accurately meet the temperature requirements of the MEMS wafer or device 10. The loaded temperature can be between 120 and 150°C .

According to the load requirements of the dynamic test, an AC voltage of a certain frequency and amplitude can be passed through the piezoelectric ceramic 4 to cause periodic displacement changes to provide vibration, and the voltage of the driving power supply of the piezoelectric ceramic 4 can be controlled by the computer and frequency changes, so as to achieve vibration loading on the MEMS wafer or device 10, the highest frequency of vibration can reach above 10KHz, and the maximum amplitude in the plane vertical direction can reach 10um. At this time, its vibration has a certain delay relative to the excitation voltage. During the dynamic test, the stroboscopic laser is irradiated on the MEMS wafer or device 10 through the light-transmitting sheet 9 with a precise time delay relative to the vibration driving power supply, and is connected with The vibrations of the MEMS wafer or device 10 are precisely synchronized.

Claims (2)

1. a dynamic test loading device for MEMS disc or device, comprising light-transmitting sheet, cavity, support and support plate, is characterized in that: light-transmitting sheet (9) is placed on the opening end face of cavity (1), It forms a sealed cavity with the cavity (1), and the electrode (21) is installed on the cavity (1), with an air charging port (6), a vacuum port (20) and a vacuum gauge interface (22), and the bracket (5) is fixed On the base of the cavity (1), the adjusting screw (3) is installed in the base of the bracket (5), the piezoelectric ceramic (4) is placed in the bracket (5), and its lower end is connected with the adjusting screw (3), The upper end joins with the support (5), and the support plate (13) is fixed on the support (5), and the disc bead (14) is fixed with the support plate (13). 2. The dynamic test loading device for MEMS wafers or devices according to claim 1, characterized in that: a heating plate (11) is arranged between the wafer bead (14) and the support plate (13).