阅读说明：本技术 一种光刻机上台面板位置调节方法、调节机构及光刻机 (Position adjusting method and mechanism for upper table panel of photoetching machine and photoetching machine ) 是由 霍锦充 于 2020-12-23 设计创作，主要内容包括：本发明涉及光刻机技术领域,更具体地说,它涉及一种光刻机上台面板位置调节方法以及应用该调节方法的调节机构和光刻机,其中,上述的上台面板位置调节方法包括以下步骤：分别测量上台面板的各个角与光刻机下台面板之间的距离；以上台面板的一个角与下台面板之间的距离为基准,将上台面板其它角与下台面板之间的距离分别与该基准进行比较,并根据比较结果对上台面板所述其它角的位置进行调节,使上台面板的各个角与下台面板之间的距离一致。根据本发明的技术方案,其可以对上台面板各个角的位置进行调节,当上台面板的各个角与下台面板之间的距离一致时,可以使上台面板与下台面板平行,从而上台面板上的掩模板与下台面板上的晶圆也平行。(The invention relates to the technical field of photoetching machines, in particular to a position adjusting method for an upper table panel of a photoetching machine, an adjusting mechanism applying the adjusting method and the photoetching machine, wherein the position adjusting method for the upper table panel comprises the following steps: respectively measuring the distance between each corner of the upper table panel and the lower table panel of the photoetching machine; the distance between one corner of the upper table board and the lower table board is taken as a reference, the distances between other corners of the upper table board and the lower table board are respectively compared with the reference, and the positions of the other corners of the upper table board are adjusted according to the comparison result, so that the distances between each corner of the upper table board and the lower table board are consistent. According to the technical scheme of the invention, the positions of the corners of the upper table panel can be adjusted, and when the distances between the corners of the upper table panel and the lower table panel are consistent, the upper table panel and the lower table panel can be parallel, so that the mask plate on the upper table panel is also parallel to the wafer on the lower table panel.)

1. A method for adjusting the position of a top deck plate of a photoetching machine is characterized by comprising the following steps:

step S1: respectively measuring the distance between each angle of the upper table panel (6) and the lower table panel (9) of the photoetching machine;

step S2: the distance between one corner of the upper table panel (6) and the lower table panel (9) is taken as a reference, the distances between other corners of the upper table panel (6) and the lower table panel (9) are respectively compared with the reference, and the positions of the other corners of the upper table panel (6) are adjusted according to the comparison result, so that the distances between the corners of the upper table panel (6) and the lower table panel (9) are consistent.

2. The method of claim 1, wherein the top platen (6) has four corners, and the step S2 is specifically as follows:

taking the maximum distance Lmax between the four corners of the upper table panel (6) and the lower table panel (9) as a reference, respectively taking the distances between the other three corners of the upper table panel (6) and the lower table panel (9) as M1, M2 and M3, respectively, and respectively lifting the other three corners of the upper table panel (6), wherein the other three corners are respectively self-lifted by distances of L1, L2 and L3; wherein the content of the first and second substances,

ln = Lmax-Mn, n is 1, 2 or 3.

3. The method of claim 1, wherein the top platen (6) has four corners, and the step S2 is specifically as follows:

taking the minimum distance Lmin between the four corners of the upper table panel (6) and the lower table panel (9) as a reference, and respectively reducing the other three corners of the upper table panel (6) by M1, M2 and M3, wherein the distances between the other three corners of the upper table panel (6) and the lower table panel (9) are respectively L1, L2 and L3; wherein the content of the first and second substances,

ln = Mn-Lmin, n being 1, 2 or 3.

4. A position adjusting mechanism for an upper table panel of a photoetching machine is characterized by comprising a rack (5), a sensor (8), a controller and a driving mechanism, wherein the upper table panel (6) can be arranged on the rack (5) in a floating manner;

the sensor (8) is used for respectively measuring the distance between each angle of the upper table panel (6) and the lower table panel (9) of the photoetching machine;

the controller is used for comparing the distances between other corners of the upper table panel (6) and the lower table panel (9) with the reference as the reference, and controlling the driving mechanism to drive the other corners of the upper table panel (6) to move according to the comparison result so as to enable the distances between the corners of the upper table panel (6) and the lower table panel (9) to be consistent.

5. The upper stage plate position adjusting mechanism of a lithography machine according to claim 4,

be equipped with mounting groove (62) on frame (5), last deck plate (6) are used for placing in mounting groove (62), frame (5) each angle department of last deck plate (6) all is equipped with backstop piece (7), wherein, all is equipped with elastic component (14) between the corresponding angle of each backstop piece (7) and last deck plate (6).

6. The upper stage plate position adjusting mechanism of a lithography machine according to claim 5,

each stop block (7) is detachably arranged on the frame (5);

each stop block (7) is provided with a first accommodating groove (71) for accommodating one end of the elastic piece (14), and each corner of the upper table panel (6) is provided with a second accommodating groove (61) for accommodating the other end of the elastic piece (14).

7. The upper stage plate position adjusting mechanism of a lithography machine according to any one of claims 4 to 6,

the number of the sensors (8) is equal to that of the corners of the upper table top board (6), and the sensors are arranged at the corresponding corners of the upper table top board (6) in a one-to-one correspondence manner.

8. The upper stage plate position adjusting mechanism of a lithography machine according to any one of claims 4 to 6,

the driving mechanism comprises screw rod motors (13), the number of the screw rod motors (13) is equal to that of the angles of the upper table top plate (6) and corresponds to the angles of the upper table top plate one by one, and each screw rod motor (13) is used for controlling and driving the corresponding angle of the upper table top plate (6) to move.

9. The upper stage plate position adjusting mechanism of a lithography machine according to claim 8,

the output end of each screw rod motor (13) is connected with a driving rod (12), a guide hole for extending each driving rod (12) is arranged on the lower table top plate (9), and each screw rod motor (13) drives the corresponding angular motion of the upper table top plate (6) through the driving rod (12).

10. A lithography machine, characterized by comprising the upper stage plate position adjusting mechanism of the lithography machine according to any one of claims 4 to 9.

Technical Field

The invention relates to the technical field of photoetching machines, in particular to a position adjusting method for an upper table top plate of a photoetching machine, an adjusting mechanism applying the adjusting method and the photoetching machine.

Background

Photolithography, which is a process of sequentially transferring chip patterns on a series of masks to corresponding layers of a silicon wafer by exposure, is a very important process in the semiconductor manufacturing process and is considered as a core step in the large-scale integrated circuit manufacturing. A series of complex and time-consuming photolithography processes in semiconductor manufacturing are mainly performed by corresponding photolithography machines.

The existing photoetching machine comprises an upper table top plate and a lower table top plate, a mask plate is fixed on the upper table top plate, a wafer is placed on the lower table top plate, and in order to improve the processing precision, the mask plate is generally required to be parallel to the wafer, so how to ensure that the mask plate is parallel to the wafer becomes a technical problem which needs to be solved urgently in the field.

Disclosure of Invention

In view of the above, the present invention provides a method for adjusting a position of a top platen of a lithography machine, and an adjusting mechanism and a lithography machine using the adjusting method, and mainly solves the technical problems that: how to ensure that the mask plate on the upper table top plate is parallel to the wafer on the lower table top plate.

In order to achieve the above purpose, the present invention mainly provides the following technical solutions.

In one aspect, an embodiment of the present invention provides a method for adjusting a position of a top plate of a lithography machine, including:

step S1: respectively measuring the distance between each corner of the upper table panel and the lower table panel of the photoetching machine;

step S2: the distance between one corner of the upper table board and the lower table board is taken as a reference, the distances between other corners of the upper table board and the lower table board are respectively compared with the reference, and the positions of the other corners of the upper table board are adjusted according to the comparison result, so that the distances between each corner of the upper table board and the lower table board are consistent.

Optionally, the upper deck has four corners, and step S2 specifically includes: taking the maximum distance Lmax between the four corners of the upper table panel and the lower table panel as a reference, respectively taking the distances between the other three corners of the upper table panel and the lower table panel as M1, M2 and M3, respectively, and respectively lifting the other three corners of the upper table panel, wherein the other three corners respectively have self-lifting distances of L1, L2 and L3; wherein Ln = Lmax-Mn, and n is 1, 2 or 3.

Optionally, the upper deck has four corners, and step S2 specifically includes: respectively lowering the other three corners of the upper table panel by taking the minimum distance Lmin between the four corners of the upper table panel and the lower table panel as a reference, wherein the distances between the other three corners of the upper table panel and the lower table panel are respectively M1, M2 and M3, and the respective lowered distances of the other three corners are respectively L1, L2 and L3; wherein Ln = Mn-Lmin, n is 1, 2 or 3.

On the other hand, the embodiment of the invention also provides a position adjusting mechanism for an upper table panel of a lithography machine, which comprises a rack, a sensor, a controller and a driving mechanism, wherein the upper table panel is arranged on the rack in a floating manner; the sensor is used for respectively measuring the distance between each corner of the upper table panel and the lower table panel of the photoetching machine; the controller is used for comparing the distances between other corners of the upper table panel and the lower table panel with the reference as the reference, and controlling the driving mechanism to drive the other corners of the upper table panel to move according to the comparison result so as to enable the distances between the corners of the upper table panel and the lower table panel to be consistent.

Optionally, a mounting groove is formed in the rack, the upper deck plate is used for being placed in the mounting groove, stop blocks are arranged at each corner of the upper deck plate, and elastic pieces are arranged between each stop block and the corresponding corner of the upper deck plate.

Optionally, each stop block is detachably arranged on the frame; each backstop piece all is equipped with the first storage tank that is used for holding elastic component one end, and each angle department of last deck plate all is equipped with the second storage tank that is used for holding the elastic component other end.

Optionally, the number of the sensors is equal to the number of the corners of the upper deck plate, and the sensors are arranged at the corresponding corners of the upper deck plate in a one-to-one correspondence manner.

Optionally, the driving mechanism includes lead screw motors, the number of the lead screw motors is equal to the number of the corners of the upper deck plate and corresponds to the corners of the upper deck plate one by one, and each lead screw motor is used for controlling and driving the corresponding corner of the upper deck plate to move.

Optionally, the output end of each lead screw motor is connected with a driving rod, the lower deck plate is provided with a guide hole for extending each driving rod, and each lead screw motor drives the corresponding angular motion of the upper deck plate through the driving rod.

In another aspect, an embodiment of the present invention further provides a lithography machine, which may include any one of the above-mentioned upper stage plate position adjusting mechanisms of the lithography machine.

By the technical scheme, the method for adjusting the position of the upper table panel of the photoetching machine, the adjusting mechanism applying the method and the photoetching machine at least have the following beneficial effects:

because the positions of the corners of the upper table panel can be adjusted, when the distances between the corners of the upper table panel and the lower table panel are consistent, the upper table panel can be parallel to the lower table panel. And because the mask plate is fixed on the upper table top plate, the wafer is also kept fixed relative to the lower table top plate, so that the mask plate on the upper table top plate can be parallel to the wafer on the lower table top plate when the upper table top plate is parallel to the lower table top plate.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings.

Drawings

FIG. 1 is a block flow diagram of a method for adjusting a position of a platen on a lithography machine according to an embodiment of the present invention;

FIG. 2 is a schematic block diagram of a first example of adjusting the position of the countertop;

FIG. 3 is a schematic, diagrammatic view of a second example of adjusting the position of the countertop;

FIG. 4 is a schematic structural diagram of a position adjustment mechanism for a top platen of a lithography machine according to an embodiment of the present invention;

FIG. 5 is a top view of the upper deck panel when mounted on the frame;

FIG. 6 is a cross-sectional view taken along line A-A of FIG. 5;

fig. 7 is a schematic structural view of the upper deck plate.

Reference numerals: 1. the 1 st corner of the upper deck plate; 2. 2 nd corner of the upper deck plate; 3. the 3 rd corner of the upper deck plate; 4. the 4 th corner of the upper deck plate; 5. a frame; 6. a top deck plate; 7. a stop block; 8. a sensor; 9. a lower deck plate; 10. a mask plate; 11. a wafer; 12. a drive rod; 13. a screw motor; 14. an elastic member; 15. connecting blocks; 61. a second accommodating groove; 62. mounting grooves; 71. a first receiving groove.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that, if directional indications (such as up, down, left, right, front, and back … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative positional relationship between the components, the movement situation, and the like in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

As shown in fig. 1, an embodiment of the invention provides a method for adjusting a position of a top plate of a lithography machine, which includes the following steps:

step S1: the distance between each corner of the upper table 6 and the lower table 9 of the lithography machine is measured.

Step S2: the distance between one corner of the upper deck plate 6 and the lower deck plate 9 is used as a reference, the distances between the other corners of the upper deck plate 6 and the lower deck plate 9 are respectively compared with the reference, and the positions of the other corners of the upper deck plate 6 are adjusted according to the comparison result, so that the distances between the corners of the upper deck plate 6 and the lower deck plate 9 are consistent.

Because the mask plate 10 is fixed on the upper table top plate 6, the upper table top plate 6 can drive the mask plate 10 thereon to move together, when the distances between each corner of the upper table top plate 6 and the lower table top plate 9 are consistent, the upper table top plate 6 and the lower table top plate 9 can be parallel, and therefore the mask plate 10 on the upper table top plate 6 is parallel to the wafer 11 on the lower table top plate 9.

Here, it should be noted that: the more the angle of the upper platen 6 is, the better, and the more the angle of the upper platen 6 is, the more accurate the position adjustment of the upper platen 6 by the above method is, and the higher the parallelism of the mask plate 10 and the wafer 11 is.

In a specific application example, the upper table panel 6 may be a rectangular plate, and the upper table panel 6 has four corners. The method for adjusting the position of the upper deck 6 will be described in detail below, taking the upper deck 6 having four corners as an example.

In the first example, the maximum distance Lmax between the four corners of the upper table panel 6 and the lower table panel 9 may be used as a reference, and thus the above step S2 may specifically be:

taking the maximum distance Lmax between the four corners of the upper deck plate 6 and the lower deck plate 9 as a reference, the distances between the other three corners of the upper deck plate 6 and the lower deck plate 9 are respectively M1, M2 and M3, and the other three corners of the upper deck plate 6 are respectively raised by the self-raising distances of L1, L2 and L3; wherein Ln = Lmax-Mn, and n is 1, 2 or 3.

In this first example, as shown in fig. 2, the four corners of the upper deck panel 6 may be taken as the 1 st, 2 nd, 3 rd and 4 th corners, respectively, and assuming that the distance between the 4 th corner of the four corners of the upper deck panel 6 and the lower deck panel 9 is the largest, the distance between the 4 th corner and the lower deck panel 9 is taken as a reference, and the distance between the 4 th corner and the lower deck panel 9 is Lmax, so that the 1 st corner is raised by a distance L1= Lmax-M1, the 2 nd corner is raised by a distance L2= Lmax-M2, and the 3 rd corner is raised by a distance L3= Lmax-M3. Where M1 is the distance between the 1 st corner and the lower deck plate 9, M2 is the distance between the 2 nd corner and the lower deck plate 9, and M3 is the distance between the 3 rd corner and the lower deck plate 9.

In the second example, the minimum distance Lmin between the four corners of the upper table panel 6 and the lower table panel 9 may be used as a reference, and thus the step S2 may specifically be:

taking the minimum distance between the four corners of the upper table panel 6 and the lower table panel 9 as a reference Lmin, and the distances between the other three corners of the upper table panel 6 and the lower table panel 9 are respectively M1, M2 and M3, and respectively lowering the other three corners of the upper table panel 6 by L1, L2 and L3; wherein Ln = Mn-Lmin, n is 1, 2 or 3.

In this second example, as shown in fig. 3, the four corners of the upper deck panel 6 may be taken as the 1 st, 2 nd, 3 rd and 4 th corners, respectively, and assuming that the distance between the 4 th corner of the four corners of the upper deck panel 6 and the lower deck panel 9 is the smallest, the distance between the 4 th corner and the lower deck panel 9 is taken as a reference, and the distance between the 4 th corner and the lower deck panel 9 is Lmin, so that the 1 st corner is decreased by a distance L1= M1-Lmin, the 2 nd corner is decreased by a distance L2= M2-Lmin, and the 3 rd corner is decreased by a distance L3= M3-Lmin. Where M1 is the distance between the 1 st corner and the lower deck plate 9, M2 is the distance between the 2 nd corner and the lower deck plate 9, and M3 is the distance between the 3 rd corner and the lower deck plate 9.

Of course, in other examples, any other distance between the four corners of the upper table board 6 and the lower table board 9 may be used as a reference, and details are not described herein.

As shown in fig. 4 and 5, an embodiment of the present invention further provides a position adjustment mechanism for a top plate of a lithography machine, which may include a frame 5, a sensor 8, a controller, and a driving mechanism. The upper deck plate 6 is floatably provided on the frame 5 so that each corner of the upper deck plate 6 can be driven to ascend and descend. In a specific application example, the rack 5 may be provided with a mounting groove 62, and the upper deck 6 is configured to be placed in the mounting groove 62. The frame 5 is provided with a stop block 7 at each corner of the upper deck 6, as shown in fig. 6, an elastic member 14 is provided between each stop block 7 and the corresponding corner of the upper deck 6, and the elastic member 14 may be a spring or flexible plastic. Wherein each elastic member 14 can provide a force to the corresponding corner of the upper deck plate 6 relatively close to the bottom of the mounting groove 62, and each corner of the upper deck plate 6 can be driven to move between the stop member and the bottom surface of the mounting groove 62.

The above-mentioned sensors 8 are used to measure the distance between each corner of the upper table 6 and the lower table 9 of the lithography machine, respectively. In a specific application example, the number of the sensors 8 may be equal to the number of the corners of the upper deck 6, and the sensors may be disposed at the corresponding corners of the upper deck 6 in a one-to-one correspondence. In the present example, each sensor 8 is used to measure the distance between a respective corner on the upper deck plate 6 and the lower deck plate 9. The sensor 8 may be a distance sensor or the like.

The controller is used for comparing the distances between the other corners of the upper table panel 6 and the lower table panel 9 with the reference of the distance between one corner of the upper table panel 6 and the lower table panel 9, and controlling the driving mechanism to drive the other corners of the upper table panel 6 to move according to the comparison result so as to enable the distances between the corners of the upper table panel 6 and the lower table panel 9 to be consistent.

The controller may be a processor or a PLC, wherein the controller takes a distance between one corner of the upper table panel 6 and the lower table panel 9 as a reference, compares distances between other corners of the upper table panel 6 and the lower table panel 9 with the reference, and controls the driving mechanism according to a comparison result, and a specific operation manner of the control may refer to the above description of the method for adjusting the position of the upper table panel 6, and is not described herein again.

In the above example, the controller can adjust the positions of the corners of the upper table panel 6 to make the upper table panel 6 parallel to the lower table panel 9. Since the mask plate 10 is fixed to the upper platen 6 and the wafer 11 is also fixed to the lower platen 9, the mask plate 10 on the upper platen 6 can be made parallel to the wafer 11 on the lower platen 9 even when the upper platen 6 and the lower platen 9 are parallel to each other.

For the convenience of mounting the upper deck plate 6, preferably, each of the aforementioned stop blocks 7 is detachable with respect to the frame 5, for example, each of the stop blocks 7 may be connected with the frame 5 by a screw, etc. In this way, the respective stopper blocks 7 can be mounted after the mask plate 10 is placed in the mounting groove 62, so as to prevent the respective stopper blocks 7 from obstructing the placement of the mask plate 10.

As shown in fig. 6, each of the stop blocks 7 may be provided with a first receiving groove 71, and each corner of the upper deck plate 6 may be provided with a second receiving groove 61, wherein the first receiving groove 71 is used for receiving one end of the elastic element 14, and the second receiving groove 61 is used for receiving the other end of the elastic element 14. Specifically, when the elastic member 14 is placed between the stopper and the upper deck 6, one end of the elastic member 14 abuts against the bottom surface of the first receiving groove 71, and the other end abuts against the bottom surface of the second receiving groove 61, and since the first receiving groove 71 and the second receiving groove 61 limit the two ends of the elastic member 14, the elastic member 14 can be prevented from shaking, and the installation stability of the elastic member 14 is improved.

As shown in fig. 4, the aforementioned driving mechanism may include lead screw motors 13, the number of the lead screw motors 13 is equal to the number of the corners of the upper table panel 6, and the lead screw motors 13 are in one-to-one correspondence, and each lead screw motor 13 is used for controlling the corresponding corner motion of the upper table panel 6 by the controller. The motion precision of the screw motor 13 is high, and the displacement of each angle of the upper table panel 6 can be accurately controlled.

The output end of each screw motor 13 can be connected with a driving rod 12, and the lower deck plate 9 is provided with a guide hole for extending each driving rod 12, wherein each screw motor 13 drives the corresponding angular motion of the upper deck plate 6 through the driving rod 12. In a specific application example, the lower deck plate 9 may be provided with guide sleeves, the number of the guide sleeves is equal to the number of the driving rods 12, and the guide sleeves are in one-to-one correspondence, and each guide sleeve is provided with the guide hole. In the above example, each screw motor 13 is located below the upper deck 6, and the screw motor 13 applies a force to a corresponding corner of the upper deck 6 through the drive lever 12 to push the corresponding corner of the upper deck 6 to rise. When the driving rod 12 of the screw motor 13 retracts, the elastic member 14 releases the elastic force, and the elastic member 14 pushes the corresponding corner of the upper deck plate 6 to descend. Therefore, the lifting adjustment of each corner of the upper table panel 6 can be realized through the matching of the screw rod motor 13 and the elastic piece 14.

As shown in fig. 7, the upper deck 6 may be provided with connecting blocks 15, the number of the connecting blocks 15 is equal to the number of the driving mechanisms, and the driving mechanisms are in one-to-one correspondence with each other, and the driving mechanisms drive the corresponding angular movement of the upper deck 6 by pushing each connecting block 15. Wherein, each connecting block 15 all can be dismantled relatively to last deck plate 6, can be connected with last deck plate 6 through the screw for example to can in time change when receiving wearing and tearing.

Embodiments of the present invention further provide a lithography machine, which may include any one of the above-described lithography machine upper deck position adjustment mechanisms. In this example, since the lithography machine employs the above-described upper stage plate position adjustment mechanism, it is possible to adjust the positions of the corners of the upper stage plate 6 so that the upper stage plate 6 is parallel to the lower stage plate 9. Since the mask plate 10 is fixed to the upper platen 6 and the wafer 11 is also fixed to the lower platen 9, the mask plate 10 on the upper platen 6 can be made parallel to the wafer 11 on the lower platen 9 even when the upper platen 6 and the lower platen 9 are parallel to each other.

The working principle and preferred embodiments of the present invention are described below.

The invention aims to design a position adjusting method for an upper table panel of a photoetching machine, an adjusting mechanism applying the adjusting method and the photoetching machine, wherein the position adjusting method for the upper table panel of the photoetching machine can be realized by adopting the following steps of S1: respectively measuring the distance between each corner of the upper table panel 6 and the lower table panel 9 of the photoetching machine; for example, the distance between each corner of the upper table 6 and the lower table 9 of the lithography machine may be measured by using distance sensors 8, and the number of the distance sensors 8 is equal to the number of the corners of the upper table 6 and corresponds to one another. Step S2: with reference to the distance between one corner of the upper deck plate 6 and the lower deck plate 9, for example, the maximum distance Lmax between each corner of the upper deck plate 6 and the lower deck plate 9 may be used as a reference, or the minimum distance Lmin between each corner of the upper deck plate 6 and the lower deck plate 9 may be used as a reference. Then the distance between the other corners of the upper deck 6 and the lower deck 9 is compared with the reference, and the positions of the other corners of the upper deck 6 are adjusted according to the comparison result, so that the distances between the corners of the upper deck 6 and the lower deck 9 are consistent. The operation in step S2 may be performed by a controller such as a processor or a PLC, and the controller controls the driving mechanism to adjust the positions of the other corners of the upper table panel 6 according to the comparison result. The driving mechanism may include lead screw motors 13, the number of the lead screw motors 13 is equal to the number of the corners of the upper table 6, and the lead screw motors 13 correspond to each other one by one, and each lead screw motor 13 is used for controlling and driving the corresponding corner motion of the upper table 6.

Here, it should be noted that: the upper deck plate 6 is designed in a floating manner, and four corners of the upper deck plate can be driven to lift. The upper table board 6 is placed in the installation groove 62 of the frame 5, the frame 5 is provided with a stop block 7 at each corner of the upper table board 6, an elastic member 14 is arranged between each stop block 7 and the corresponding corner of the upper table board 6, and the elastic member 14 can be a spring or flexible plastic cement. Each lead screw motor 13 is located below the upper deck 6, and the lead screw motor 13 applies force to a corresponding corner of the upper deck 6 through the driving lever 12 to push the corresponding corner of the upper deck 6 to rise. When the driving rod 12 of the screw motor 13 retracts, the elastic member 14 releases the elastic force, and the elastic member 14 pushes the corresponding corner of the upper deck plate 6 to descend. Therefore, the lifting adjustment of each corner of the upper table panel 6 can be realized through the matching of the screw rod motor 13 and the elastic piece 14.

Here, it should be noted that: in the case of no conflict, a person skilled in the art may combine the related technical features in the above examples according to actual situations to achieve corresponding technical effects, and details of various combining situations are not described herein.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may occur to those skilled in the art without departing from the principle of the invention, and are considered to be within the scope of the invention.