MEMS packaging method

Abstract

The invention relates to an MEMS (Micro Electro Mechanical System) packaging method. The method comprises the following steps of S1, bonding a device layer wafer on a substrate; s2, etching the device layer wafer to obtain an acceleration sensor structure and a gyroscope structure; s3, in a nitrogen atmosphere, pre-bonding an upper cover plate on the acceleration sensor structure and the gyroscope structure, so that an acceleration sensor structure cavity and a gyroscope structure cavity between the upper cover plate and the substrate are filled with nitrogen; and S4, eliminating nitrogen in the cavity of the gyroscope structure, and bonding the acceleration sensor structure and the gyroscope structure on the upper cover plate to obtain the gyroscope structure vacuum chamber. The acceleration sensor chip and the gyroscope chip are prepared on one substrate through MEMS packaging, the preparation process is shortened, the manufacturing period and cost of the MEMS chips are reduced, combined packaging of the two chips is achieved through combined nesting of different types of MEMS packaging modes, and the packaging efficiency is improved. The packaging volume is reduced, and the space utilization rate and the integration capability are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of micro-nano inertial sensing technology, and particularly to a MEMS packaging method. Background Art

[0002] A high-precision inertial measurement unit (IMU) generally consists of three single-axis accelerometers, three single-axis gyroscopes, and corresponding application-specific integrated circuits. The two can measure the axial acceleration and angular velocity signals respectively, calculate the motion attitude of the moving object through data processing, and then complete navigation, guidance, and timing.

[0003] In high-precision inertial sensors, the MEMS accelerometer needs to work in an underdamped state in an N2 atmosphere, while the MEMS gyro needs to work in a vacuum atmosphere. Therefore, there are usually two methods in the prior art. One is to use the form of independent packaging of a single MEMS chip, and the other is to first vacuum-pack the MEMS accelerometer and the MEMS gyro chip together, and then open a hole above the MEMS accelerometer to fill N2 and perform secondary packaging to ensure that different MEMS chips can work normally. However, both of these packaging forms require multiple wafer-level packaging, with a long preparation cycle and high cost. Summary of the Invention

[0004] The purpose of the present invention is to provide a MEMS packaging method, which can at least solve some defects in the prior art.

[0005] To achieve the above purpose, the embodiments of the present invention provide the following technical solution: A MEMS packaging method includes the following steps: S1, bonding the device layer wafer on the substrate; S2, etching the device layer wafer to obtain an accelerometer structure and a gyro structure; S3, in a nitrogen atmosphere, pre-bonding the upper cover plate on the accelerometer structure and the gyro structure, so that the accelerometer structure cavity and the gyro structure cavity between the upper cover plate and the substrate are filled with nitrogen; S4, removing the nitrogen in the gyro structure cavity, and bonding both the accelerometer structure and the gyro structure on the upper cover plate to obtain a gyro structure vacuum chamber.

[0006] Further, in the S4 step, the method of bonding the upper cover plate on the accelerometer structure is specifically: Making glass paste at the pre-bonding position between the accelerometer structure and the upper cover plate; Press the upper cover plate onto the acceleration sensor structure, and heat the glass paste during the application of pressure. The glass paste melts to bond the upper cover plate to the acceleration sensor structure.

[0007] Furthermore, in the step S3, the specific manner in which the upper cover plate is pre-bonded to the gyro structure is as follows: Fabricate sacrificial blocks at the pre-bonding positions between the gyro structure and the upper cover plate; Fabricate metal eutectic points on the surface of the gyro structure facing the upper cover plate, and the sacrificial blocks and the metal eutectic points are arranged opposite to each other; Dock the sacrificial blocks with the metal eutectic points.

[0008] Furthermore, the specific manner of the step S4 is as follows: Release the sacrificial blocks, and extract the nitrogen gas in the cavity of the gyro structure through the gaps formed after the release of the sacrificial blocks; The bonding position of the upper cover plate falls on the metal eutectic points; Bond the upper cover plate and the device layer wafer through the metal eutectic points to obtain the vacuum chamber of the gyro structure.

[0009] Furthermore, the specific manner of releasing the sacrificial blocks is as follows: Press the upper cover plate onto the acceleration sensor structure and the gyro structure, and heat the sacrificial blocks during the application of pressure, and at the same time introduce oxygen into the sacrificial blocks, so that the bonding position of the upper cover plate falls on the metal eutectic points.

[0010] Furthermore, the specific manner of heating the sacrificial blocks during the application of pressure is as follows: Prepare an upper clamping plate and a lower clamping plate arranged opposite to each other. Place the substrate on the lower clamping plate, and press the upper clamping plate on the upper cover plate; Close the upper clamping plate and the lower clamping plate, and heat the upper clamping plate and / or the lower clamping plate.

[0011] Furthermore, take the upper cover plate substrate, fabricate a plurality of bumps on the upper surface of the substrate; fabricate the sacrificial blocks on the corresponding bumps of the gyro structure for the upper cover plate; flip the substrate so that the bumps are pre-bonded to the metal eutectic points through the sacrificial blocks.

[0012] Furthermore, before obtaining the acceleration sensor structure and the gyro structure, first etch the device layer wafer to obtain an overflow groove.

[0013] Furthermore, before the step S1: Etch downward on the substrate to form a plurality of grooves, and adjacent two grooves are separated by a scribing channel, and support anchors are provided in both adjacent two grooves; Deposit multiple insulating layers and multiple metal layers alternately on the etched substrate in sequence; Open a number of first through-holes in the insulating layer between two adjacent metal layers to make the two adjacent metal layers conduct; Remove the uppermost insulating layer on the support anchor points and the area outside the grooves to expose the metal layer, and the area where the exposed metal layer is located is the bonding area.

[0014] Furthermore, both the S3 step and the S4 step are completed by a bonding machine.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: By realizing the preparation of the acceleration sensor chip and the gyro chip on one substrate through MEMS packaging, the preparation process is shortened, the manufacturing cycle and cost of the MEMS chip are reduced, and through the combined nesting of different types of MEMS-level packaging methods, the joint packaging of the two chips is realized, the packaging volume is reduced, and the space utilization rate and integration ability are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the substrate of a MEMS packaging method provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of the etched substrate of a MEMS packaging method provided by an embodiment of the present invention; Figure 3 It is a schematic diagram of depositing the first insulating layer of a MEMS packaging method provided by an embodiment of the present invention; Figure 4 It is a schematic diagram of fabricating the first metal layer of a MEMS packaging method provided by an embodiment of the present invention; Figure 5 It is a schematic diagram of depositing the second insulating layer and opening through-holes of a MEMS packaging method provided by an embodiment of the present invention; Figure 6 It is a schematic diagram of fabricating the second metal layer of a MEMS packaging method provided by an embodiment of the present invention; Figure 7 It is a schematic diagram of depositing the third insulating layer and removing the third insulating layer on the support anchor points and the area outside the grooves of a MEMS packaging method provided by an embodiment of the present invention; Figure 8 It is a schematic diagram of bonding the device layer wafer of a MEMS packaging method provided by an embodiment of the present invention; Figure 9 It is a schematic diagram of thinning the device layer wafer and fabricating an overflow groove and a metal eutectic point of a MEMS packaging method provided by an embodiment of the present invention; Figure 10Schematic diagram of opening a through hole in the area of the device layer wafer of a MEMS packaging method provided by an embodiment of the present invention facing the groove; Figure 11 Schematic diagram of fabricating bumps on the upper cover of a MEMS packaging method provided by an embodiment of the present invention; Figure 12 Schematic diagram of fabricating glass paste and sacrificial blocks of a MEMS packaging method provided by an embodiment of the present invention; Figure 13 Schematic diagram of pre - bonding the upper cover plate and the device layer wafer in a nitrogen atmosphere of a MEMS packaging method provided by an embodiment of the present invention; Figure 14 Schematic diagram of making the cavity of the gyro chip into a vacuum chamber and completing the bonding of the upper cover plate and the device layer wafer of a MEMS packaging method provided by an embodiment of the present invention; In the reference numerals: 1 - substrate; 10 - support anchor; 11 - scribing lane; 12 - groove; 2 - first insulating layer; 3 - first metal layer; 4 - second insulating layer; 40 - first through hole; 5 - second metal layer; 6 - third insulating layer; 7 - device layer wafer; 70 - overflow groove; 71 - metal eutectic point; 72 - second through hole; 8 - upper cover plate; 80 - bump; 81 - glass paste; 82 - sacrificial block; 90 - nitrogen; 91 - vacuum chamber. Detailed implementation manners

[0017] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0018] Please refer to Figures 1 to 14, an embodiment of the present invention provides a MEMS packaging method, including the following steps: S1, bonding a device layer wafer 7 on a substrate 1; S2, etching the device layer wafer 7 to obtain an acceleration sensor structure and a gyro structure; S3, in a nitrogen atmosphere, pre-bonding an upper cover plate 8 on the acceleration sensor structure and the gyro structure, so that the acceleration sensor structure cavity and the gyro structure cavity between the upper cover plate 8 and the substrate 1 are filled with nitrogen; S4, removing the nitrogen in the gyro structure cavity, and bonding both the acceleration sensor structure and the gyro structure on the upper cover plate 8 to obtain a gyro structure vacuum chamber. In this embodiment, through MEMS packaging, the acceleration sensor chip and the gyro chip are fabricated on a single substrate, shortening the fabrication process, reducing the cycle and cost of MEMS chip manufacturing, and through the combined nesting of different types of MEMS-level packaging methods, the joint packaging of the two chips is achieved, reducing the packaging volume and improving the space utilization rate and integration ability. Specifically, Figure 7 As shown, it is divided by a dicing lane 11 (that is, Figure 13 and Figure 14 divided by the dotted line on the left and right), the left side is the acceleration sensor structure, and the right side is the gyro structure. As Figure 8 shown, continue to bond the device layer wafer 7. After the device layer wafer 7 is bonded, as Figure 13 shown, pre-bond the upper cover plate 8 on the device layer wafer 7 in a nitrogen 90 atmosphere. As Figure 14 shown, after removing the nitrogen 90 in the cavity between the gyro structure and the upper cover plate 8, make this cavity into a vacuum chamber 91. After completing the bonding of the upper cover plate 8 and the device layer wafer 7, a primary MEMS-level packaging of the acceleration sensor chip and the gyro chip can be achieved. As Figure 14 shown, after preparation, the left side of the dicing lane 11 is the acceleration sensor chip, and the right side is the gyro chip. First, divide the acceleration sensor structure manufacturing area and the gyro structure manufacturing area on the base, and there is a dicing lane 11 between the acceleration sensor structure manufacturing area and the gyro structure manufacturing area; then the acceleration sensor structure and the gyro structure can be obtained by etching the device layer wafer. Preferably, Figures 1 to 14 This is the overall manufacturing process step of this method, which is carried out in sequence. The structure shown in the next figure is a sequential step change based on the structure shown in the previous figure. Preferably, both the S3 step and the S4 step are completed by a bonder.

[0019] Please refer to Figure 12 、 Figure 13 and Figure 14, in the step S3, in the step S4, the specific way of bonding the upper cover plate 8 to the acceleration sensor structure is as follows: Make glass paste 81 at the pre-bonding position between the acceleration sensor structure and the upper cover plate 8; Press the upper cover plate 8 onto the acceleration sensor structure, and heat the glass paste 81 during the application of pressure, and the glass paste 81 melts to bond the upper cover plate 8 to the acceleration sensor structure. In this embodiment, the pre-bonding method between the acceleration sensor structure and the upper cover plate 8 is bonding with glass paste 81. The upper cover plate 8 is pressed onto the device layer wafer 7 and heated during the pressing process, so that the glass paste 81 can be melted and bonded to the upper cover plate 8. Combining the above embodiments, after pumping out nitrogen through the gap released by the sacrificial block, continue to pump until the vacuum chamber is maintained, and then heat the glass paste and continue to apply pressure in its molten state, so that the bonding position of the upper cover plate falls on the metal eutectic point, completing the bonding between the bonding position of the upper cover plate and the metal eutectic point, and at the same time, the acceleration sensor structure and the upper cover plate are also bonded.

[0020] Please refer to Figure 12 , Figure 13 and Figure 14, in the step S3, the specific manner in which the upper cover plate is pre-bonded to the gyro structure is as follows: sacrificial blocks 82 are fabricated at the pre-bonding positions of the gyro structure and the upper cover plate 8, metal eutectic points 71 are fabricated on the surface of the gyro structure facing the upper cover plate 8, the sacrificial blocks 82 and the metal eutectic points 71 are arranged opposite to each other, and the sacrificial blocks 82 are located above the metal eutectic points 71, and the sacrificial blocks 82 are docked with the metal eutectic points 71; preferably, the specific manner of the step S4 is: the sacrificial blocks 82 are released, and the nitrogen gas in the cavity of the gyro structure is pumped out through the gap formed after the release of the sacrificial blocks 82; the bonding position of the upper cover plate 8 falls on the metal eutectic points 71; the upper cover plate 8 and the device layer wafer are bonded through the metal eutectic points 71 to obtain the vacuum chamber 91 of the gyro structure. This bonding is eutectic bonding. In this embodiment, the way to fabricate the vacuum chamber 91 is to introduce sacrificial blocks 82. Before the sacrificial blocks 82 are released, due to their certain thickness, the sacrificial blocks 82 can support the upper cover plate 8 above the device layer wafer 7, and in addition, the sacrificial blocks 82 can be used to locate the pre-bonding positions. After the sacrificial blocks 82 and the metal eutectic points 71 are fabricated, the sacrificial blocks 82 are released. After the sacrificial blocks 82 disappear, the upper cover plate 8 will naturally fall at the metal eutectic points 71. Then, after the pre-bonding position of the upper cover plate 8 and the metal eutectic points 71 are bonded, the cavity between the gyro structure and the upper cover plate 8 can be sealed, thereby obtaining the vacuum chamber 91. It can be said that the action of obtaining the vacuum chamber 91 is synchronous with the bonding action. After bonding, the cavity between the gyro structure and the upper cover plate 8 is sealed. Before that, the cavity was in a vacuum state, so the vacuum chamber 91 can be obtained after sealing.

[0021] To further optimize the above solution, the specific way to release the sacrificial block 82 is as follows: Press the upper cover plate 8 onto the acceleration sensor structure and the gyro structure, and heat the sacrificial block 82 during the application of pressure. At the same time, introduce oxygen into the sacrificial block 82. After the sacrificial block 82 reacts with oxygen, it is consumed, and the bonding position of the upper cover plate 8 falls on the metal eutectic point 71. In this process, a bonding machine can be used to complete the bonding of the upper cover plate and the device layer wafer, and to complete the fabrication of the vacuum chamber. Specifically, the bonding machine can introduce oxygen, nitrogen, and evacuate the air. Preferably, the specific way to heat the sacrificial block 82 during the application of pressure is as follows: Prepare an upper clamping plate and a lower clamping plate that are oppositely arranged. Place the substrate 1 on the lower clamping plate, and press the upper clamping plate onto the upper cover plate 8; close the upper clamping plate and the lower clamping plate, and heat the upper clamping plate and / or the lower clamping plate. The bonding machine can use the upper and lower clamping plates to clamp and apply force. For example, press the upper clamping plate downward onto the upper cover plate 8, and then place the substrate 1 on the lower clamping plate. In this way, the entire structure will be clamped between the upper and lower clamping plates, and the clamping force can be provided by the upper and lower clamping plates to apply pressure. At the same time, the upper and lower clamping plates can also generate heat to provide a high-temperature environment to eliminate the sacrificial block 82. The upper and lower clamping plates can generate heat simultaneously to provide a more uniform heating environment. Of course, it is also feasible to heat only one of them. The means to eliminate the sacrificial block 82 is to cause it to react and be consumed by introducing oxygen. Any existing sacrificial block 82 material that can react with oxygen after heating can be used in this embodiment, such as polyimide. This embodiment does not limit this. After the sacrificial block 82 is consumed, since the bonding position has been well aligned, after the sacrificial block 82 is consumed, the bonding position of the upper cover plate 8 can then fall on the metal eutectic point 71. And since it is in a heating environment at this time, sufficient heat can cause the upper cover plate 8 and the metal eutectic point 71 to complete metal eutectic, thereby achieving bonding.

[0022] Please refer to Figure 11 and Figure 12In the above steps, a top cover plate 8 substrate is prepared, and several bumps 80 are formed on its upper surface. Glass paste 81 is applied to each bump 80 of the top cover plate 8 corresponding to the acceleration sensor structure, and sacrificial blocks 82 are applied to each bump 80 of the top cover plate 8 corresponding to the gyroscope structure. The substrate is flipped so that each bump 80 faces the acceleration sensor structure and the gyroscope structure, and pre-bonded thereto. In this embodiment, a top cover plate 8 substrate is prepared, and several bumps 80 are formed thereon. The spaces between adjacent bumps 80 form the cavity of the top cover plate 8 described in the above embodiment, which can also be considered as grooves 12. These bumps 80 are also the bonding locations of the top cover plate 8, through which the acceleration sensor structure and gyroscope structure below are bonded. After the bumps 80, the glass paste 81, and the sacrificial blocks 82 are formed on the top cover plate 8, the substrate is flipped so that the bumps 80 face the device layer wafer 7. This step also constitutes pre-bonding.

[0023] See also Figure 9 Before obtaining the acceleration sensor structure and the gyroscope structure, the device layer wafer 7 is first etched to obtain an overflow groove 70. In this embodiment, the overflow groove 70 can be located at the bonding position between the acceleration sensor structure and the upper cover plate 8, so that the molten excess glass paste 81 flows away from the overflow groove 70. Of course, if the gyroscope structure also has similar overflow requirements, the overflow groove can also be etched in the gyroscope structure. The overflow groove 70 can be designed in the following manner: Figure 13 As Figure 14 When the glass slurry 81 flows away from the overflow tank 70, Figure 13 In the process, the glass paste 81 has not been squeezed yet and is in a block structure. Figures 13 to 14 During the process, the upper cover plate 8 is pressed down, and the glass paste 81 is squeezed and deformed, usually as shown in FIG. Figure 14 As shown, the glass paste 81 that is squeezed out overflows to the periphery. By setting an overflow groove 70 at the bonding position, the glass paste 81 that is squeezed out can be guided away.

[0024] See also Figure 13 and Figure 14 In the step S4, the specific method of eliminating the nitrogen 90 in the cavity between the gyro structure and the upper cover plate 8 is to extract the nitrogen 90 in the cavity from the gap between the upper cover plate 8 and the gyro structure. The nitrogen 90 in the cavity can be extracted by extraction, that is, Figure 13 As shown, the nitrogen 90 in the cavity on the right is extracted, specifically, the nitrogen 90 is extracted from the gap between the upper cover plate 8 and the gyro structure.

[0025] See also Figures 1 to 7, before the step S1: etching downwards on the substrate 1 to form a plurality of grooves 12, the adjacent two grooves 12 being separated by a scribing lane 11, and support anchors 10 being provided in each of the adjacent two grooves 12; sequentially and alternately depositing a plurality of insulating layers and a plurality of metal layers on the etched substrate 1; opening a plurality of first through-holes 40 in the insulating layer between two adjacent metal layers to electrically connect the two adjacent metal layers; removing the support anchors 10 and the uppermost insulating layer in the area outside the grooves 12 to expose the metal layer, and the area where the exposed metal layer is located being the bonding area. Preferably, the sequential and alternate deposition method is specifically as follows: first depositing a first insulating layer 2 on the etched substrate 1; fabricating a first metal layer 3 on the first insulating layer 2; depositing a second insulating layer 4 on the first metal layer 3, and opening a plurality of first through-holes 40 in the second insulating layer 4 in the grooves 12 to expose the first metal layer 3; fabricating a second metal layer 5 on the second insulating layer, and electrically connecting the second metal layer 5 in the grooves 12 to the first metal layer 3; depositing a third insulating layer 6 on the second metal layer 5, and removing the third insulating layer 6 on the support anchors 10 and in the area outside the grooves 12 to expose the second metal layer, and the area where the second metal layer is located being the bonding area. In this embodiment, the number of insulating layers and the number of metal layers can be selected as required, and are not limited to the number of layers shown in this embodiment, but it should be noted that a sufficient number of first through-holes 40 are designed to electrically connect two adjacent metal layers. Through the above method, the acceleration sensor structure and the gyro structure can be fabricated simultaneously on the same substrate 1. This device-level wafer-level co-packaging greatly shortens the preparation process, reduces the cycle and cost of MEMS chip manufacturing, and moreover, through the combined nesting of different types of MEMS-level packaging methods, the co-packaging of the two chips is realized, reducing the packaging volume and improving the space utilization rate and integration ability.

[0026] To further optimize the above solution, please refer to Figure 10 , the etching of the device-level wafer 7 is specifically as follows: opening a second through-hole 72 in the area of the device-level wafer 7 opposite to the grooves 12 to penetrate the cavity between the upper cover 8 and the acceleration sensor structure and the cavity between the upper cover 8 and the gyro structure. In this embodiment, by designing the second through-hole 72, the cavity of the upper cover 8 can be penetrated with the cavity of the acceleration sensor structure, and the cavity of the upper cover 8 can be penetrated with the cavity of the gyro structure, so that the grooves 12 in the substrate 1 and the cavity in the upper cover 8 are both filled with nitrogen 90 or a vacuum chamber 91 is formed. As Figure 10 , the two sides of the scribing lane 11 are respectively the acceleration sensor structure and the gyro structure. As Figure 13 and Figure 14, on the left and right of the dashed line are respectively the acceleration sensor structure and the gyro structure with upper cover plates added.

[0027] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A MEMS packaging method, characterized in that, The steps are as follows: S1. Bond the device layer wafer to the substrate; S2. Etch the device layer wafer to obtain an acceleration sensor structure and a gyro structure; S3. Under a nitrogen atmosphere, pre-bond the upper cover plate to the acceleration sensor structure and the gyro structure, so that the acceleration sensor structure cavity and the gyro structure cavity between the upper cover plate and the substrate are filled with nitrogen; S4. Eliminate the nitrogen in the gyro structure cavity, and bond both the acceleration sensor structure and the gyro structure to the upper cover plate to obtain a gyro structure vacuum chamber.

2. The MEMS packaging method according to claim 1, wherein In step S4, the specific manner of bonding the upper cover plate to the acceleration sensor structure is as follows: Fabricate glass paste at the pre-bonding position between the acceleration sensor structure and the upper cover plate; Press the upper cover plate onto the acceleration sensor structure, and heat the glass paste during the application of pressure, and the glass paste melts to bond the upper cover plate to the acceleration sensor structure.

3. The MEMS packaging method according to claim 1, characterized in that In step S3, the specific manner of pre-bonding the upper cover plate to the gyro structure is as follows: Fabricate a sacrificial block at the pre-bonding position between the gyro structure and the upper cover plate; Fabricate a metal eutectic point on the surface of the gyro structure facing the upper cover plate, and the sacrificial block and the metal eutectic point are arranged opposite to each other; Dock the sacrificial block with the metal eutectic point.

4. The MEMS packaging method according to claim 3, wherein The specific manner of step S4 is as follows: Release the sacrificial block, and extract the nitrogen in the gyro structure cavity through the gap formed after the release of the sacrificial block; The bonding position of the upper cover plate falls on the metal eutectic point; Bond the upper cover plate and the device layer wafer through the metal eutectic point to obtain the gyro structure vacuum chamber.

5. The MEMS packaging method according to claim 4, characterized in that, The specific manner of releasing the sacrificial block is: Press the upper cover plate onto the acceleration sensor structure and the gyro structure, and heat the sacrificial block during the application of pressure, and at the same time introduce oxygen into the sacrificial block, so that the bonding position of the upper cover plate falls on the metal eutectic point.

6. The MEMS packaging method according to claim 5, wherein, The specific manner of heating the sacrificial block during the application of pressure is as follows: Prepare an upper clamping plate and a lower clamping plate arranged opposite to each other. The lower clamping plate supports the substrate, and the upper clamping plate presses on the upper cover plate; Close the upper clamping plate and the lower clamping plate, and heat the upper clamping plate and / or the lower clamping plate.

7. The MEMS packaging method according to claim 3, wherein Take an upper cover plate substrate, fabricate a plurality of bumps on the upper surface of the substrate; fabricate the sacrificial blocks on the bumps of the gyro structure corresponding to the upper cover plate; turn over the substrate, so that the bumps are pre-bonded to the metal eutectic points through the sacrificial blocks.

8. The MEMS packaging method according to claim 1, characterized in that: Before obtaining the acceleration sensor structure and the gyro structure, first etch the device layer wafer to obtain an overflow groove.

9. The MEMS packaging method according to claim 1, wherein, Before step S1, it further includes: Etch downward on the substrate to form a plurality of grooves, and adjacent two grooves are separated by a scribing channel, and support anchors are provided in both adjacent two grooves; Deposit a plurality of insulating layers and a plurality of metal layers alternately on the etched substrate in sequence; Open a plurality of first through holes in the insulating layer between two adjacent metal layers to make the two adjacent metal layers conduct. Remove the uppermost insulating layer on the support anchor points and the area outside the grooves to expose the metal layer, and the area where the exposed metal layer is located is the bonding area.

10. The MEMS packaging method according to claim 1, characterized in that, Both the step S3 and the step S4 are completed by a bonding machine.

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