CN106586951A - Shock wave excitation apparatus capable of realizing excitation of MEMS microstructure in vacuum environment - Google Patents

Abstract

The invention discloses a shock wave excitation device capable of exciting MEMS microstructures in a vacuum environment. The needle electrode unit pointing to the microstructure unit is provided on the board; the microstructure unit includes a mounting sleeve, and an elastic base is pressed at one end of the mounting hole of the mounting sleeve, and the elastic base is in the shape of a circular sheet with a The ring-shaped boss is equipped with a plate electrode through an insulating sleeve in the elastic base, and a MEMS microstructure is installed on the inner side of the elastic base; an optical glass plate is pressed into the other end of the installation hole; a vacuum joint is arranged radially on the outer wall of the installation sleeve ; The needle electrode and the plate electrode are respectively electrically connected to the two poles of the high-voltage capacitor, and the two poles of the high-voltage capacitor are respectively electrically connected to the positive and negative poles of the high-voltage power supply. The structure of the device is firmly installed, the operation is simple and safe, and it is convenient to test the dynamic characteristic parameters of the microstructure in a vacuum environment.

Description

A shock excitation device capable of exciting MEMS microstructures in a vacuum environment

technical field

The invention belongs to the technical field of micromechanical electronic systems, and in particular relates to a shock wave excitation device capable of exciting MEMS microstructures in a vacuum environment.

Background technique

Due to the advantages of low cost, small size and light weight, MEMS microdevices have broad application prospects in many fields such as automobile, aerospace, information communication, biochemistry, medical treatment, automatic control and national defense. For many MEMS devices, the micro-displacement and micro-deformation of their internal microstructures are the basis for the realization of device functions. Therefore, accurate testing of dynamic characteristic parameters such as the amplitude, natural frequency, and damping ratio of these microstructures has become the key to developing MEMS products. important content.

In order to test the dynamic characteristic parameters of the microstructure, it is first necessary to make the microstructure vibrate, that is, to excite the microstructure. Due to the small size, light weight and high natural frequency of MEMS microstructures, the excitation methods and excitation devices in traditional mechanical mode testing cannot be applied to the vibration excitation of MEMS microstructures. In the past two decades, researchers at home and abroad have made a lot of explorations on the vibration excitation methods of MEMS microstructures, and have developed some excitation methods and corresponding excitation devices that can be used for MEMS microstructures. Among them, She Dongsheng et al. introduced a shock-based base excitation device in the article "Shock Wave-Based MEMS Microstructure Base Shock Excitation Method". This device has the advantages of large excitation bandwidth and wide application range. application potential. However, this device still has the following disadvantages: first, a cross spring is used in the device as a base structure for carrying microstructures, and the microstructure and its installation structure are bonded to the top center of the cross spring. When the structure is excited, the cross spring will produce a large bending deformation; on the one hand, this will cause the deformation of the microstructure mounting plate, resulting in damage to the microstructure; on the other hand, this will make the gap between the microstructure mounting plate and the cross spring The cured glue between them bears a lot of tension. After multiple excitations, the glue is easy to crack, and the microstructure mounting plate will loosen and break away from the cross spring piece; secondly, in the device, the cross spring piece, ceramic piece and plate The electrodes are stacked up and down, and are fixed by glue bonding between two adjacent parts. This bonding structure is not strong enough, and after multiple discharges, the layers are easy to separate from each other; Third, in the device, the feeding mechanism can only be adjusted manually, and cannot realize automatic feeding, resulting in cumbersome discharge operation and poor safety; fourth, since the microstructure is completely exposed to the air, when it is necessary to test the microstructure in a vacuum environment When the dynamic characteristics are lower, since the discharge cannot be performed in a vacuum environment, the device cannot meet the demand.

Contents of the invention

The technical problem to be solved by the present invention is to provide a shock wave excitation device that can excite MEMS microstructures in a vacuum environment. The structure of the device is firmly installed, easy and safe to operate, and it is convenient to test the dynamic characteristics of MEMS microstructures in a vacuum environment. parameter.

In order to solve the above problems, the present invention adopts the following technical solutions:

A shock wave excitation device that can excite MEMS microstructures in a vacuum environment, including a substrate, on which a manual three-axis displacement platform and a support are arranged, and on the Z-axis slide plate of the manual three-axis displacement platform. Needle electrode unit; the needle electrode unit includes a right-angle connecting plate for connecting the Z-axis sliding plate, two support plates parallel to each other are arranged on the right-angle connection plate, and guides arranged in parallel are provided between the two support plates The shaft and the lead screw are provided with a drive plate on the guide shaft. The drive plate and the lead screw are connected by a screw nut. A stepping motor coaxially connected with the lead screw is provided on the outside of one of the support plates. A needle electrode is installed through the insulation of the ceramic tube, and the needle electrode points to the microstructure unit arranged on the upper end of the support;

The microstructure unit includes an installation sleeve installed on the upper end of the support, and a stepped installation hole is provided in the installation sleeve, and an elastic base is sealed and pressed on the end of the corresponding needle electrode in the installation hole through the first pressure plate, and the elastic base is clamped on the Between the first pressure plate and the annular step in the installation hole, the elastic base is in the shape of a circular sheet with an annular boss in the middle, and a plate electrode is inlaid in the center hole outside the elastic base through an insulating sleeve, and the inner side of the elastic base The MEMS microstructure is installed through the microstructure mounting plate; the other end of the mounting hole is sealed and pressed with an optical glass plate through the second pressure plate, and the mounting hole forms a closed cavity through the optical glass plate and the elastic base. The MEMS microstructure The structure is located in the airtight cavity; a vacuum joint communicating with the airtight cavity is arranged radially on the outer wall of the installation sleeve;

The needle electrode and the plate electrode are respectively electrically connected to the two poles of the high-voltage capacitor, and a first air switch is provided between the needle electrode and the high-voltage capacitor to control on-off; the two poles of the high-voltage capacitor are respectively electrically connected to the positive and negative poles of the high-voltage power supply , and the on-off is controlled by the second air switch.

As a further preference, the ceramic tube passes through the transmission plate vertically and is fixed by a jacking wire arranged at the upper end of the transmission plate.

As a further preference, the support is in the shape of a stepped shaft, the lower end of which is a large-diameter end and is covered with a flange, the flange is connected to the base plate by screws and the support is fixed on the base plate, the upper end of the support is connected to the mounting sleeve Connected by thread.

As a further preference, the first pressure plate is fixed in the port corresponding to one end of the needle electrode in the installation hole by screws uniformly distributed around the circumference, and a circular positioning slot is provided on the annular step surface corresponding to one end of the first pressure plate in the installation sleeve, The elastic base is arranged in the positioning slot through clearance fit and fixed by top wires evenly distributed on the first pressing plate.

As a further preference, sealing rings are interposed between the annular stepped surfaces at both ends of the installation hole, the optical glass plate and the elastic base, so as to improve the sealing performance of the closed cavity.

As a further preference, the central hole of the elastic base is a tapered blind hole, the outer edge of the insulating sleeve is tapered and is fitted and bonded with the taper of the tapered blind hole, the inner wall of the insulating sleeve is connected to the outer edge of the plate electrode They are plugged and bonded through the conical surfaces that cooperate with each other to enhance the firmness of the plate electrode installation.

As a further preference, the microstructure mounting plate is connected to the center of the inner side of the elastic base by screws uniformly distributed around the circumference, and the MEMS microstructure is bonded to the microstructure mounting plate.

The beneficial effects of the present invention are:

(1) Since the elastic base is in the shape of a circular sheet and has a ring-shaped boss in the middle, when the MEMS microstructure is excited, the central area of the elastic base will not be bent and deformed, so that it will not make the elastic base installed on the elastic base The microstructure mounting plate at the inner center is deformed, so that the microstructure and the microstructure mounting plate will not separate from each other.

(2) Since the central hole of the elastic base is stepped, and the plate electrode is inlaid in the large hole on the outside through the insulating sleeve, the plate electrode is installed more firmly, and the parts will not be separated after multiple discharges.

(3) Since the needle electrode unit driven by the stepping motor is installed on the Z-axis sliding plate of the manual three-axis translation stage, it has two functions of manual feeding and automatic feeding; in the preparation of the shock wave excitation experiment stage, the relative position of the needle electrode and the plate electrode can be adjusted by manual feeding, and the stepper motor can be controlled to discharge by automatic feeding during the shock wave excitation experiment, which ensures the flexible adjustment of the two electrodes. The relative position between the two electrodes ensures the safety during the discharge experiment, and the operation is simple and safe.

(4) Since the installation hole in the installation sleeve forms a closed cavity through the optical glass plate and the elastic base, the MEMS microstructure is located in the airtight cavity, and a vacuum joint is provided on the outer wall of the installation sleeve, so it can pass through the vacuum joint. The vacuum environment is applied to the MEMS microstructure, and the shock wave can be generated by the discharge to excite the microstructure; the elastic base is designed as a part of the closed cavity, which solves the problem that the shock wave cannot be used to excite the MEMS microstructure in a vacuum environment .

Description of drawings

Fig. 1 is a schematic diagram of the three-dimensional structure of the present invention.

Figure 2 is a front view of the present invention.

Fig. 3 is a right side view of Fig. 2 .

Fig. 4 is a three-dimensional structure diagram of the needle electrode unit of the present invention.

Fig. 5 is a three-dimensional structure diagram of the microstructure unit of the present invention.

FIG. 6 is a partially enlarged view of the microstructure unit in FIG. 3 .

Fig. 7 is a cross-sectional view along line A-A of Fig. 6 .

Fig. 8 is a circuit block diagram of the present invention.

In the figure: 1. base plate, 2. manual three-axis translation stage, 3. bottom plate, 4. screw, 5. microstructure unit, 501. vacuum joint, 502. mounting sleeve, 503. screw, 504. first pressure plate, 505 .Top wire, 506. Elastic base, 507. Plate electrode, 508. Insulation sleeve, 509. Screw, 510. Second pressure plate, 511. Optical glass plate, 512. Sealing ring, 513. MEMS microstructure, 514. Screw, 515. Microstructure mounting plate, 6. Needle electrode unit, 601. Right-angle connecting plate, 602. Stepper motor, 603. Screw, 604. Screw, 605. Support plate, 606. Guide shaft, 607. Screw nut, 608. Screw, 609. Shaft sleeve, 610. Transmission plate, 611. Top wire, 612. Ceramic tube, 613. Needle electrode, 614. Lead screw, 7. Flange, 8. Support, 9. The first air switch, 10. Second air switch, 11. High voltage capacitor, 12. High voltage power supply.

detailed description

As shown in Figures 1-3, the present invention relates to a shock wave excitation device that can excite MEMS microstructures in a vacuum environment, including a substrate 1, on which a manual three-axis translation stage 2 and a The support 8, the manual three-axis displacement table 2 is installed on a base plate 3, and the base plate 3 is fixed on the base plate 1 by screws 4. A needle electrode unit 6 is installed on the Z-axis slide plate of the manual three-axis displacement table 2 .

As shown in Figure 4, the needle electrode unit 6 includes a right-angle connecting plate 601 fixed on the Z-axis sliding plate by screws, and two supporting plates 605 parallel to each other are fixed on the right-angle connecting plate 601 by screws. A guide shaft 606 and a lead screw 614 arranged in parallel up and down are arranged between the support plates 605, and a transmission plate 610 is sleeved on the guide shaft 606, and the corresponding guide shaft 606 on the transmission plate 610 is inlaid with a guide shaft 606 to slide. Cooperating bushing 609, the two ends of guide shaft 606 are fixed on the two support plates 605 by screws 604, the lead screw 614 is rotatably installed between the two support plates 605, and the transmission plate 610 and the lead screw 614 are connected by using The screw 608 is fixed on the screw nut 607 on the transmission plate 610, and the stepping motor 602 coaxially connected with the lead screw 614 is fixed on the outside of one of the support plates 605 by a screw 603, and the upper end of the transmission plate 610 is installed insulated through a ceramic tube 612 There is a needle electrode 613 , and the ceramic tube 612 vertically passes through the driving plate 610 and is fixed by a top wire 611 arranged at the upper end of the driving plate 610 . The rear part of the needle electrode 613 is embedded in the ceramic tube 612 , and the tip of the front end of the needle electrode 613 points to the microstructure unit 5 arranged on the upper end of the support 8 .

As shown in Figures 5-7, the microstructure unit 5 includes a mounting sleeve 502 mounted on the upper end of the support 8, the support 8 is in the shape of a stepped shaft, and its lower end is a large-diameter end and is sleeved with a flange 7. The flange 7 is connected to the base plate 1 by screws and the support 8 is fixed on the base plate 1 , and the upper end of the support 8 is screwed to the screw hole provided on the bottom surface of the mounting sleeve 502 . A stepped installation hole is provided in the installation sleeve 502, the inner diameter of the middle part of the installation hole is much smaller than the inner diameter of the ports at both ends, and an elastic base 506 is sealed and pressed by the first pressing plate 504 in the installation hole corresponding to the end of the needle electrode 613, and the elastic base 506 is clamped. Hold between the first pressure plate 504 and the annular step in the installation hole, the elastic base 506 is in the shape of a circular thin sheet and has an annular boss in the middle, and one end of the corresponding needle electrode 613 in the central hole of the elastic base 506 passes through the insulation The sleeve 508 is inlaid with a plate electrode 507, and the inside of the elastic base 506 is equipped with a MEMS microstructure 513 through a microstructure mounting plate 515; the other end of the mounting hole is sealed and pressed with an optical glass plate 511 through a second pressure plate 510, and the mounting hole An airtight cavity is formed by the optical glass plate 511 and the elastic base 506, and the MEMS microstructure 513 is located in the airtight cavity; a vacuum joint 501 communicating with the airtight cavity is installed radially on the outer wall of the installation sleeve 502 .

The first pressing plate 504 is fixed in the port corresponding to one end of the needle electrode 613 in the installation hole through the screws 503 evenly distributed on the circumference, and a circular positioning slot is provided on the annular step surface corresponding to the end of the first pressing plate 504 in the installation sleeve 502 , the elastic base 506 is arranged in the positioning slot through clearance fit and fixed by the top screws 505 evenly distributed on the first pressing plate 504 around the circumference, and the elastic base 506 can be further compressed by tightening the top screws. The second pressing plate 510 is connected to the installation sleeve 502 through the screws 509 evenly distributed around the circumference, and the optical glass plate 511 is fixed in the port at the other end of the installation hole. Sealing rings 512 are interposed between the annular stepped surfaces at both ends of the installation hole, the optical glass plate 511 and the elastic base 506 to improve the sealing performance of the airtight cavity.

The central hole of the elastic base 506 is a tapered blind hole, the outer edge of the insulating sleeve 508 is tapered and fits and is bonded with the taper of the tapered blind hole, the inner wall of the insulating sleeve 508 and the outer edge of the plate electrode 507 They are plugged and bonded through mutually matched conical surfaces to enhance the firmness of the installation of the plate electrode 507 . The insulating sleeve 508 is preferably a ceramic sleeve. The center of the microstructure mounting plate 515 is provided with a through hole and is connected to the center of the inner side of the elastic base 506 by screws 514 uniformly distributed around the circumference, and the MEMS microstructure 513 is glued on the microstructure mounting plate 515 .

As shown in Figure 8, the shock wave excitation device is also provided with a high-voltage capacitor 11 and a high-voltage power supply 12, the needle electrode 613 and the plate electrode 507 are respectively electrically connected to the two poles of the high-voltage capacitor 11 through wires, and the plate electrode 507 is provided with a Screw holes for connecting wires. A first air switch 9 is provided between the needle electrode 613 and the high-voltage capacitor 11 to control on-off; the two poles of the high-voltage capacitor 11 are electrically connected to the positive and negative poles of the high-voltage power supply 12, and are controlled on-off by the second air switch 10 .

When in use, first place the first air switch 9 and the second air switch 10 in the off state, adjust the manual three-axis displacement stage 2 so that the needle tip of the needle electrode 613 is aligned with the center position of the plate electrode 507, and ensure that the distance between them The distance is greater than the maximum air breakdown gap after the high-voltage capacitor 11 is fully charged; secondly, use a vacuum pump to connect the vacuum connector 501 to evacuate the inside of the airtight cavity; thirdly, close the second air switch 10, and use the high-voltage power supply 12 for high-voltage The capacitor 11 is charged, and when the charging is completed, the second air switch 10 is disconnected; finally, the first air switch 9 is closed, and the stepper motor 602 is controlled to make the needle electrode 613 slowly approach the plate electrode 507, when the needle tip of the needle electrode 613 and the plate When the distance between the electrodes 507 satisfies the air breakdown condition under the current charging voltage, the air gap is broken down, the discharge is completed and a shock wave is generated, and the shock excitation of the MEMS microstructure in a vacuum environment is realized.

Although the embodiment of the present invention has been disclosed as above, it is not limited to the use listed in the specification and implementation, it can be applied to various fields suitable for the present invention, and it can be easily understood by those skilled in the art Therefore, the invention is not limited to the specific details and examples shown and described herein without departing from the general concept defined by the claims and their equivalents.

Claims (7)

1. a kind of shock wave exciting bank that can enter row energization to MEMS micro-structurals under vacuum conditions, including substrate, is characterized in that： Manual three-shaft displacement platform and bearing are provided with substrate, on the Z axis slide carriage of manual three-shaft displacement platform pin electrode unit is provided with；Institute State the right-angle connecting plate that pin electrode unit includes for connecting Z axis slide carriage, two pieces are provided with right-angle connecting plate and are parallel to each other Gripper shoe, is provided with the axis of guide and leading screw being arranged in parallel between two pieces of gripper shoes, and driver plate is arranged with the axis of guide, passes Connected by screw between dynamic plate and leading screw, wherein one piece of gripper shoe outside is provided with the stepper motor coaxially connected with leading screw, There is pin electrode by earthenware insulating mounting in driver plate upper end, pin electrode points to the microstructure unit for being arranged on bearing upper end；

The microstructure unit includes being arranged on the installation set of bearing upper end, stepped installing hole is provided with installation set, in peace Correspondence pin electrode one end is pressed with elastic base by the first pressing plate for sealing in dress hole, and elastic base is clamped in the first pressing plate with peace Between ring ladder in dress hole, elastic base is annular flake and is provided with annular boss in the middle, in elastic base Plate electrode is installed with by insulation sleeve in outer side center hole, elastic base inner side is provided with the micro- knots of MEMS by micro-structural installing plate Structure；The other end is pressed with optical flat by the second pressing plate for sealing in installing hole, and the installing hole passes through optical flat An airtight cavity is formed with elastic base, the MEMS micro-structurals are located in the airtight cavity；In installation set outer wall radially It is provided with a vacuum adapter communicated with airtight cavity；

The pin electrode and plate electrode are electrically connected respectively with the two poles of the earth of high-voltage capacitance, and is provided between pin electrode and high-voltage capacitance One air switch controls break-make；The two poles of the earth of the high-voltage capacitance are electrically coupled to respectively the both positive and negative polarity of high voltage power supply, and by second Air switch controls break-make.

2. a kind of shock wave excitation that can enter row energization to MEMS micro-structurals under vacuum conditions according to claim 1 is filled Put, it is characterized in that：The earthenware passes perpendicularly through driver plate and is fixed by being located at the jackscrew of driver plate upper end.

3. a kind of shock wave excitation that can enter row energization to MEMS micro-structurals under vacuum conditions according to claim 1 is filled Put, it is characterized in that：The bearing is ladder shaft-like, and its lower end is bigger diameter end and is arranged with ring flange, and ring flange passes through with substrate Mode connects for screw is simultaneously fixed on bearing on substrate, and bearing upper end is threaded connection with installation set.

4. a kind of shock wave excitation that can enter row energization to MEMS micro-structurals under vacuum conditions according to claim 1 is filled Put, it is characterized in that：First pressing plate is fixed on the port of correspondence pin electrode one end in installing hole by the screw of circumference uniform distribution It is interior, circular locating groove is provided with the annular step tread of corresponding first pressing plate one end in installation set, the elastic base passes through Gap cooperation is located in locating groove and the jackscrew by circumference uniform distribution on the first pressing plate is fixed.

5. a kind of shock wave excitation that can enter row energization to MEMS micro-structurals under vacuum conditions according to claim 4 is filled Put, it is characterized in that：The sandwiched respectively between the annular step tread and optical flat and elastic base at two ends in the installing hole There is sealing ring, to improve the sealing of airtight cavity.

6. a kind of shock wave excitation that can enter row energization to MEMS micro-structurals under vacuum conditions according to claim 4 or 5 Device, is characterized in that：The centre bore of the elastic base be tapered blind hole, the insulation sleeve outer rim be taper and with the taper The grafting of blind hole taper fit and bonding, by the taper seat grafting that cooperates and glue between insulation sleeve inwall and plate electrode outer rim Connect.

7. a kind of shock wave excitation that can enter row energization to MEMS micro-structurals under vacuum conditions according to claim 1 is filled Put, it is characterized in that：Center of the micro-structural installing plate by the mode connects for screw of circumference uniform distribution on the inside of elastic base, MEMS Micro-structural is bonded on micro-structural installing plate.