CN216084841U

CN216084841U - Wafer adsorption device and wafer transfer device

Info

Publication number: CN216084841U
Application number: CN202122952813.9U
Authority: CN
Inventors: 胡雨; 戴冬云
Original assignee: Jiangsu Third Generation Semiconductor Research Institute Co Ltd
Current assignee: Jiangsu Third Generation Semiconductor Research Institute Co Ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2022-03-18
Anticipated expiration: 2031-11-29

Abstract

The utility model discloses a wafer adsorption device and a wafer transfer device. The wafer adsorption apparatus includes: the fixed cylinder is internally provided with an open cavity; the sucker is arranged at the first end of the fixed cylinder and is provided with an adsorption space formed by enclosing an adsorption surface, and the adsorption space is communicated with the cavity; an elastic mechanism disposed within the cavity; the piston is movably arranged in the cavity, is in sealed contact with the cavity wall of the cavity, is elastically matched with the elastic mechanism, and can move between a first station and a second station under the resultant force action of external force applied from the outside and elastic force provided by the elastic mechanism. The wafer adsorption device provided by the embodiment of the utility model can be used for carrying out nondestructive transfer on wafers of various specifications when carrying out adsorption fixing and transfer on the wafers, and does not need to maintain external force applied from the outside.

Description

Wafer adsorption device and wafer transfer device

Technical Field

The utility model relates to a fixed adsorption device, in particular to a wafer adsorption device and a wafer transfer device, and belongs to the technical field of wafer fixing and transfer.

Background

When testing or transferring a wafer, the wafer is usually picked up by tweezers, and then placed on a testing machine or a target position, and then the tweezers are released to place the wafer on the target position. Since the operator usually uses tweezers to pick up the wafer in the above operation, there are many hidden troubles, such as: 1) the wafer is clamped by tweezers and is easy to slide off; 2) the tweezers easily scratch the surface of the wafer; 3) the force is not easy to control.

SUMMERY OF THE UTILITY MODEL

The present invention is directed to a wafer suction device and a wafer transfer device, which overcome the disadvantages of the prior art.

In order to achieve the purpose of the utility model, the technical scheme adopted by the utility model comprises the following steps:

an embodiment of the present invention provides a wafer adsorption apparatus, including:

the fixed cylinder is internally provided with an open cavity;

the sucker is arranged at the first end of the fixed cylinder and is provided with an adsorption space formed by enclosing an adsorption surface, and the adsorption space is communicated with the cavity;

an elastic mechanism disposed within the cavity;

the piston is movably arranged in the cavity, is in sealed contact with the cavity wall of the cavity, is elastically matched with the elastic mechanism, and can move between a first station and a second station under the resultant action of external force applied from the outside and elastic force provided by the elastic mechanism;

when the adsorption surface of the sucker is in sealing contact with the wafer and external force applied from the outside is smaller than the elastic force, the piston moves from the second station to the first station under the driving of the resultant force, the air pressure in a closed space formed by the piston, the cavity wall of the cavity, the adsorption surface and the wafer is smaller than or equal to the external atmospheric pressure, and the wafer is fixed on the sucker under the action of first pressure difference between the inside and the outside of the closed space;

when the external force applied by the outside is larger than the elastic force, the piston moves from the first station to the second station under the driving of the resultant force, the air pressure in a closed space formed by the piston, the cavity wall of the cavity, the adsorption surface and the wafer in an enclosing mode is larger than the atmospheric pressure of the outside, and the wafer is separated from the adsorption surface of the sucker under the action of a second pressure difference between the inside and the outside of the closed space.

The embodiment of the utility model also provides a wafer transfer device which comprises the wafer adsorption device.

Compared with the prior art, the utility model has the advantages that:

1) the wafer adsorption device provided by the embodiment of the utility model can realize nondestructive fixed adsorption and transfer of the wafer;

2) according to the wafer adsorption device provided by the embodiment of the utility model, the wafer adsorption device can adapt to wafers of various sizes;

3) the wafer adsorption device provided by the embodiment of the utility model can be used for carrying out nondestructive transfer on wafers of various specifications when carrying out adsorption fixing and transfer on the wafers, and does not need to maintain external force applied from the outside;

4) the wafer adsorption device provided by the embodiment of the utility model has a simpler structure and is convenient to maintain and store.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1a is an exploded view of a wafer chuck device according to an exemplary embodiment of the present invention;

FIG. 1b is an exploded cross-sectional view of a wafer chuck device in accordance with an exemplary embodiment of the present invention;

fig. 2a is a schematic diagram of a wafer chuck device in a compression-ready state according to an exemplary embodiment of the present invention;

FIG. 2b is a schematic cross-sectional view of a wafer chuck device in a ready-to-compress state according to an exemplary embodiment of the present invention;

fig. 3a is a schematic structural diagram of a wafer chuck device in a release suction state according to an exemplary embodiment of the present invention;

fig. 3b is a schematic cross-sectional view of a wafer chuck device in a release-chucking state according to an exemplary embodiment of the present invention;

fig. 4a is a schematic diagram illustrating a wafer chuck device in a relaxed release state according to an exemplary embodiment of the present invention;

FIG. 4b is a schematic cross-sectional view of a wafer chuck device in a relaxed release state in accordance with an exemplary embodiment of the present invention;

fig. 5a, 5b, and 5c are schematic views of a wafer suction device according to an exemplary embodiment of the present invention, in which an elastic mechanism is in a release relaxed state, a compression prepared state, and a release suction state.

Detailed Description

In view of the deficiencies in the prior art, the inventors of the present invention have made extensive studies and extensive practices to provide technical solutions of the present invention. The technical solution, its implementation and principles, etc. will be further explained as follows.

the fixed cylinder is internally provided with an open cavity;

an elastic mechanism disposed within the cavity;

In some more specific embodiments, the piston comprises a piston rod and a piston head, the piston head is arranged at one end of the piston rod close to the suction cup, at least the piston head is in sealing contact with the cavity wall of the cavity, and the piston rod is in elastic fit with the elastic mechanism.

In some specific embodiments, a first limiting structure is fixedly disposed on a cavity wall of the cavity, a second limiting structure is fixedly disposed on the piston rod, and the elastic mechanism is disposed between the first limiting structure and the second limiting structure.

In some more specific embodiments, the elastic mechanism is sleeved on the piston rod.

In some more specific embodiments, the resilient mechanism comprises a spring.

In some more specific embodiments, the first stop structure is disposed between the second stop structure and the piston head.

In some more specific embodiments, the first limit formation is located on the path of movement of the piston head.

In some more specific embodiments, the first limiting structure is an arc-shaped structure or an annular structure disposed along the circumferential direction of the cavity wall.

In some specific embodiments, the second limiting structure is an arc-shaped structure or an annular structure arranged along the circumferential direction of the piston rod.

In some more specific embodiments, the piston head is removably connected to the piston rod; and/or the piston head is in threaded connection with the piston rod.

In some more specific embodiments, the surface of the piston head that contacts the wall of the cavity is provided with an encapsulating layer.

In some more specific embodiments, the wafer chucking apparatus further comprises: the driving rod can be connected with the piston rod, when the piston moves between a first station and a second station, a part of the driving rod is always exposed outside the cavity from the second end of the fixed cylinder, wherein the second end is opposite to the first end.

In some specific embodiments, when the piston moves between the first position and the second position, the end of the piston rod away from the suction cup is always located inside the cavity.

In some more specific embodiments, the drive rod is removably connected to the piston rod.

In some more specific embodiments, the drive rod is threadedly connected to the piston rod.

In some more specific embodiments, the drive rod is integral with the piston rod.

In some more specific embodiments, the drive rod is disposed coaxially with the piston rod and piston head.

In some more specific embodiments, the fixed cylinder is detachably connected to the suction cup.

In some more specific embodiments, the suction cup is sleeved at the first end of the fixed cylinder.

In some specific embodiments, a first step structure is arranged at a first end of the fixed cylinder, a second step structure is arranged on the sucker, and the first step structure and the second step structure are matched with each other to enable the sucker and the fixed cylinder to form a connection state.

In some more specific embodiments, the sucking disc includes sucking disc main part and fixed cover, fixed cover with sucking disc main part fixed connection, the sucking disc main part on form the adsorption plane, enclose by the adsorption plane and close the adsorption space that forms with fixed cover is linked together, the fixed setting of second stair structure is in on the inner wall of fixed cover.

In some more specific embodiments, the chuck body and the retaining sleeve of the chuck are both flexible members.

In some more specific embodiments, the suction surface has a first region capable of sealing contact with the wafer and a second region different from the first region, the second region having a gas-guide opening in communication with the cavity.

In some specific embodiments, the fixed cylinder, the piston, the elastic mechanism and the suction cup are coaxially arranged.

In some specific embodiments, the wafer transferring apparatus further includes a first driving mechanism and a second driving mechanism, the first driving mechanism is in transmission connection with the piston and at least used for applying the external force to the piston, and the second driving mechanism is in transmission connection with the fixed cylinder and at least used for transferring the wafer transferring apparatus to a designated position.

As will be described in further detail with reference to the accompanying drawings, unless otherwise specified, each component of the wafer suction device provided in the embodiments of the present invention may be commercially available, and the first driving mechanism and the second driving mechanism may be linear driving mechanisms or rotary driving mechanisms, which may be commercially available, and specific structures and related parameters thereof are not limited herein.

Referring to fig. 1a and 1b, a wafer suction apparatus includes a fixed cylinder 100, a piston rod 200, a piston head 300, a suction cup 400 and an elastic mechanism 500,

the fixed cylinder 100 is provided with an open cavity, the piston head 300 is fixedly arranged at one end of the piston rod 200 to form a piston, the piston rod 200 and the piston head 300 are jointly and movably arranged in the cavity inside the fixed cylinder 100, a gap is formed between the piston rod 200 and the cavity wall of the cavity, the piston head 300 is in sealing contact (namely, tightly attached, also understood as gapless contact) with the cavity wall of the cavity, the piston can move along the cavity under the driving of an external force, the piston head 300 is always in sealing contact with the cavity wall of the cavity in the movement process of the piston, the sucker 400 is fixedly arranged at the first end of the fixed cylinder 100,

the sucking disc 400 is provided with an adsorption space 411 formed by enclosing an adsorption surface, and the adsorption space 411 is communicated with the cavity, in particular a part of the cavity between the piston head 300 and the sucking disc 400; the elastic mechanism 500 is disposed in the cavity, and the elastic mechanism 500 is further elastically matched with the piston rod 200 and the fixed cylinder 100, so that the piston can move between the first station and the second station in the cavity under the resultant force of an external force applied from the outside and an elastic force provided by the elastic mechanism 500.

In this embodiment, when the suction surface of the chuck 400 is in sealing contact with the wafer and the external force applied from the outside is smaller than the elastic force, the piston is driven by the resultant force to move from the second station to the first station, the air pressure in the enclosed space formed by the piston head 300, the cavity wall of the cavity, the suction surface of the chuck and the wafer is smaller than or equal to the atmospheric pressure of the outside, and the wafer is fixed on the chuck 400 under the action of a first pressure difference between the inside and the outside of the enclosed space;

when the external force applied by the outside is smaller than the elastic force, the piston moves from the first station to the second station under the driving of the resultant force, the air pressure in a closed space formed by the piston head 300, the cavity wall of the cavity, the adsorption surface of the sucker and the wafer is larger than the atmospheric pressure of the outside, and the wafer is separated from the adsorption surface of the sucker under the action of a second pressure difference between the inside and the outside of the closed space.

In this embodiment, a first limiting structure 110 is fixedly disposed on a cavity wall of the cavity, a second limiting structure 230 is fixedly disposed on the piston rod 200, and the elastic mechanism 500 is disposed between the first limiting structure 110 and the second limiting structure 230, wherein the first limiting structure 110 is disposed between the second limiting structure 230 and the piston head 300, and the first limiting structure 110 is located on a motion track of the piston head 300, so that the first limiting structure 110 not only limits the elastic mechanism 500, but also limits the piston head 300.

In this embodiment, the total length of the plunger rod 200 and the plunger head 300 is less than the length of the cavity, and when the resilient mechanism 500 is in the relaxed or natural state, the end of the plunger rod 200 away from the plunger head 300 is also completely located in the cavity, i.e. the plunger rod 200 does not protrude out of the port 101 at the second end of the fixed barrel 100.

In this embodiment, the elastic mechanism 500 may be sleeved on the piston rod 200, or may be disposed on the outer circumferential surface of the piston rod 200.

It is understood that the elastic mechanisms 500 may be provided in one or more, and when the elastic mechanisms 500 are provided in one, the elastic mechanisms 500 are preferably sleeved on the piston rod 200; when the number of the elastic mechanisms 500 is multiple, the multiple elastic mechanisms 500 may be sequentially sleeved on the piston rod 200, and of course, the multiple elastic mechanisms may be arranged in parallel with the piston rod 200, and the multiple elastic mechanisms 500 surround the piston rod 200.

In this embodiment, the elastic mechanism 500 is preferably a spring, but of course, the elastic mechanism 500 may also be other elastic mechanisms known to those skilled in the art, such as an elastic sheet or an elastic column, which are capable of providing recoverable deformation, and are not listed here.

In this embodiment, the first limiting structure 110 may be an arc-shaped structure or an annular structure disposed along the circumferential direction of the cavity wall, and it can be understood that the first limiting structure 110 may be disposed in one or more than one, and when one first limiting structure 110 is adopted, it is preferable that the first limiting structure 110 is disposed in an annular structure disposed continuously along the circumferential direction of the cavity wall; when a plurality of first limit structures 110 are adopted, the plurality of first limit structures 110 are arranged at intervals along the circumferential direction of the cavity wall, and each first limit structure 110 is arranged to be an arc-shaped structure matched with the cavity wall.

It is understood that the first limiting structure 110 needs to be sufficient to resist the elastic force generated by the elastic mechanism 500 and the pushing force or pressure of the piston head 300, and therefore, the material, size, etc. of the first limiting structure 110 can be set according to specific use situations, and is not limited specifically herein.

In this embodiment, the second position-limiting structure 230 may be an arc-shaped structure or an annular structure disposed along the circumferential direction of the piston rod 200, and it is understood that the second position-limiting structure 230 may be disposed in one or more shapes, and when one second position-limiting structure 230 is adopted, it is preferable that the second position-limiting structure 230 is disposed in an annular structure disposed continuously along the circumferential direction of the piston rod 200; when a plurality of second position-limiting structures 230 are adopted, the plurality of second position-limiting structures 230 are arranged at intervals along the circumferential direction of the piston rod 200, and each second position-limiting structure 230 is arranged to be an arc-shaped structure matched with the piston rod 200.

It is understood that the second position-limiting structure 230 needs to be sufficient to resist the elastic force generated by the elastic mechanism 500, and therefore, the material, size, etc. of the second position-limiting structure 230 may be set according to specific use situations, and is not limited specifically herein.

In this embodiment, the piston head 300 is detachably connected to the piston rod 200, for example, the piston head 300 is screwed to the piston rod 200.

In this embodiment, the end of the piston rod 200 is provided with a second threaded hole 220, the piston head 300 has a second threaded connection portion 310 with a smaller diameter than the main body portion, and the piston head 300 and the piston rod 200 are fixedly connected through the threaded connection of the second threaded connection portion 310 and the second threaded hole 220.

In this embodiment, the end of the piston rod 200 is provided with a second connecting hole, the piston head 300 has a second connecting portion with a diameter smaller than that of the main body portion, and the piston head 300 and the piston rod 200 are fixedly connected by the second connecting portion being fitted into the second connecting hole, for example, the second connecting portion is in interference fit with the second connecting hole.

In this embodiment, a portion of the surface of the piston head 300 contacting the cavity wall of the cavity is provided with an encapsulating layer, which is a flexible member, and the encapsulating layer can be deformed under external pressure, so as to promote a good sealing contact relationship between the piston head 300 and the cavity wall of the cavity, and it can be understood that the whole piston head 300 may be a flexible member, and the material of the flexible member may be known to those skilled in the art, such as rubber, and is not limited herein.

In this embodiment, the suction cup 400 is sleeved at the first end of the fixed cylinder 100, and the fixed cylinder 100 is detachably connected with the suction cup 400.

In this embodiment, the first end of the fixed cylinder 100 is provided with the first step structure 120, the suction cup 400 is provided with the second step structure 421, and the first step structure 120 and the second step structure 421 are matched with each other to enable the suction cup 400 and the fixed cylinder 100 to form a connection state, it can be understood that the matching manner of the first step structure 120 and the second step structure 421 is to enable step surfaces of the first step structure 120 and the second step structure 421 to be attached to each other, it can be understood that, as can be seen from fig. 1b, the second step structure 421 has a limiting effect on the first step structure 120, so that the connection between the first step structure 120 and the second step structure is realized.

In this embodiment, the suction cup 400 includes a suction cup main body 410 and a fixing sleeve 420, the fixing sleeve 420 is fixedly connected with the suction cup main body 410, the suction cup main body 410 is formed with the suction surface, a suction space 411 formed by the suction surface being enclosed is communicated with the fixing sleeve, and the second step structure 421 is fixedly disposed on the inner wall of the fixing sleeve 420.

In this embodiment, the suction cup body 410 and the fixing sleeve 420 of the suction cup are both flexible members, and the fixing sleeve 420 is flexible, so that the fixing cylinder 100 extrudes the fixing sleeve 420 to deform the fixing sleeve 420 under the intervention of external force, so that the first end of the fixing cylinder can be separated from the limiting space in the fixing sleeve 420, and the suction cup and the fixing cylinder are separated from each other, and the detachable connection between the suction cup and the fixing cylinder is realized.

In this embodiment, the suction surface has a first region capable of being in sealing contact with the wafer and a second region different from the first region, and the second region has an air guide opening communicating with the cavity.

In this embodiment, the fixed cylinder 100, the piston rod 200, the piston head 300, the elastic mechanism 500 and the suction cup 400 are coaxially disposed.

In this embodiment, for convenience of operation, an outer rim 130 is further disposed at the second end of the fixed cylinder 100, and the outer rim 130 may be formed to extend in a radial direction of the fixed cylinder 100.

In this embodiment, the wafer adsorbing device further includes a driving rod 600, the driving rod 600 can be connected to the piston rod 200, when the piston moves between the first position and the second position, a portion of the driving rod 600 is always exposed outside the cavity from a second end of the fixed cylinder, wherein the second end is opposite to the first end.

It can be understood that when the piston moves between the first position and the second position, the end of the piston rod 200 away from the suction cup 400 is always located inside the cavity, and the driving rod 600 is mainly used for applying an external force to the piston rod.

In this embodiment, the driving rod 600 is detachably connected to the piston rod 200, for example, the driving rod 600 is connected to the piston rod 200 by a screw, or the driving rod 600 is connected to the piston rod 200 by a snap.

In this embodiment, the end of the piston rod 200 is provided with a first threaded hole 210, the driving rod 600 has a first threaded connection portion 610 with a diameter smaller than that of the main body portion, and the driving rod 600 and the piston rod 200 are fixedly connected by the first threaded connection portion 610 being in threaded connection with the first threaded hole 210.

In this embodiment, the end of the piston rod 200 is provided with a first connection hole, the piston head 300 has a first connection part with a diameter smaller than that of the main body part, and the piston head 300 and the piston rod 200 are fixedly connected by the first connection part being engaged with the first connection hole, for example, the first connection part is in interference fit with the first connection hole.

In this embodiment, the diameter of the main body portion of the driving rod 600 is smaller than the inner diameter of the cavity, i.e. there is a gap between the main body portion of the driving rod 600 and the cavity wall of the cavity.

In this embodiment, the driving rod 600 further includes a stop portion 620, the stop portion 620 is located at an end of the driving rod 600 far away from the fixed cylinder 100, and a diameter or a maximum width of the stop portion 620 is larger than an inner diameter of the cavity, so as to prevent the driving rod 600 from completely entering the cavity.

In this embodiment, the driving rod 600 is coaxially disposed with the piston rod 200 and the piston head 300.

In this embodiment, the process of performing the adsorption and desorption of the wafer by the wafer adsorption apparatus mainly includes a compression preparation process, a desorption adsorption process, and a desorption relaxation process:

a compression preparation process, please refer to fig. 2a and 2b, applying a pushing force to the driving rod 600 to make the piston head 300 move toward the direction close to the suction cup until moving to a second station, in which the elastic mechanism 500 is continuously compressed, the elastic mechanism 500 is in and keeps a compressed state, and the applied pushing force is greater than the elastic action (which may be referred to as an elastic force) generated by the elastic mechanism 500, in which the state of the elastic mechanism 500 is as shown in fig. 5 b;

releasing the suction process, referring to fig. 3a and 3b, making the suction surface of the chuck 400 adhere to the surface of the wafer 700 and ensuring a gapless fit between the two, wherein the piston head 300, the cavity wall of the cavity, the suction surface of the chuck and the wafer enclose to form a closed space 800, and removing or gradually removing or reducing the thrust applied to the driving rod 600, that is, making the thrust smaller than the elastic force provided by the elastic mechanism 500 or making the thrust zero, at this time, the piston head 300 moves in the direction away from the chuck until the first station, the volume of the closed space 800 increases, and the pressure in the closed space 800 decreases to be smaller than the external atmospheric pressure, the wafer 700 is sucked and fixed on the chuck under the action of the pressure difference between the two sides, and in this process, the state of the elastic mechanism 500 is as shown in fig. 5 c;

releasing and releasing process, please refer to fig. 4a and 4b, applying a pushing force to the driving rod 600 again to make the piston head 300 move toward the direction of the suction cup 400, in this process, the volume of the enclosed space 800 is reduced by compression, and the pressure in the enclosed space 800 increases until it is greater than the external atmospheric pressure, the wafer 700 adsorbed on the suction cup 400 is separated from the suction cup 400 under the driving of the pressure difference between the two sides, so as to release the wafer, the state of the elastic mechanism 500 after releasing the wafer is as shown in fig. 5a, after releasing the wafer, the pushing force applied to the driving rod 600 is removed, and the elastic mechanism 500 returns to the natural relaxation state.

The pushing force applied to the driving rod 600 may be manually applied, or may be quantitatively applied by providing a driving mechanism.

The driving mechanism in the embodiment of the present invention may adopt a driving motor or a driving cylinder known to those skilled in the art, and in the embodiment, the wafer adsorbing device may be used as a wafer transferring device and used for transferring a wafer.

In this embodiment, when the wafer is manually transferred by cooperating with the wafer adsorbing device, the driving rod 600 may be manually driven and the piston head may be driven to move between the first station and the second station in the fixed cylinder 100, so as to implement the compression preparation process and the release and suction process.

In this embodiment, when using the manpower to carry out the wafer transfer, can adjust through the size to wafer adsorption equipment to the size that combines adsorption equipment's size to the adaptive absorption corresponds the wafer of size, and can realize one-hand operation, can realize reciprocating of piston through palm etc. and can realize gripping and moving fixed cylinder through the finger, and then move the wafer to the assigned position or place the test wafer on the testboard etc..

In this embodiment, if other mechanical devices are used to replace the manual pushing force applied to the driving rod 600 and to achieve the transferring and releasing of the wafer adsorbing device and the wafer, a plurality of driving motors may be used to achieve the fixing and adsorbing, transferring and releasing of the wafer, for example, by using a mechanical arm in combination with the wafer adsorbing device, and the mechanical arm may be commercially available.

The wafer adsorption device provided by the embodiment of the utility model can realize nondestructive fixed adsorption and transfer of wafers, can adapt to wafers of various sizes, can perform nondestructive transfer on wafers of various specifications when the wafers are adsorbed, fixed and transferred, does not need to maintain external force applied from the outside, and is more convenient to use; the wafer adsorption device provided by the embodiment of the utility model has a simpler structure and is convenient to maintain and store.

It should be understood that the above-mentioned embodiments are merely illustrative of the technical concepts and features of the present invention, which are intended to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and therefore, the protection scope of the present invention is not limited thereby. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. A wafer suction device, comprising:

the fixed cylinder is internally provided with an open cavity;

an elastic mechanism disposed within the cavity;

2. The wafer chucking apparatus as set forth in claim 1, wherein: the piston comprises a piston rod and a piston head, the piston head is arranged at one end, close to the sucker, of the piston rod, at least the piston head is in sealing contact with the cavity wall of the cavity, and the piston rod is in elastic fit with the elastic mechanism.

3. The wafer chucking apparatus as set forth in claim 2, wherein: the cavity wall of the cavity is fixedly provided with a first limiting structure, the piston rod is fixedly provided with a second limiting structure, and the elastic mechanism is arranged between the first limiting structure and the second limiting structure.

4. The wafer suction device according to claim 3, wherein: the elastic mechanism is sleeved on the piston rod; and/or, the resilient mechanism comprises a spring.

5. The wafer suction device according to claim 3, wherein: the first limit structure is arranged between the second limit structure and the piston head;

and/or the first limit structure is positioned on the motion track of the piston head;

and/or the first limiting structure is an arc structure or an annular structure arranged along the circumferential direction of the cavity wall;

and/or the second limiting structure is an arc-shaped mechanism or an annular structure arranged along the circumferential direction of the piston rod.

6. The wafer chucking apparatus as set forth in claim 2, wherein: the piston head is detachably connected with the piston rod; and/or the piston head is in threaded connection with the piston rod; and/or an encapsulating layer is arranged on the partial surface of the piston head, which is in contact with the cavity wall of the cavity.

7. The wafer chucking apparatus as set forth in claim 2, further comprising: the driving rod can be connected with the piston rod, when the piston moves between a first station and a second station, a part of the driving rod is always exposed out of the cavity from a second end of the fixed cylinder, wherein the second end is opposite to the first end;

and/or when the piston moves between the first station and the second station, one end of the piston rod, which is far away from the sucker, is always positioned in the cavity;

and/or the driving rod is detachably connected with the piston rod;

and/or the driving rod is in threaded connection with the piston rod;

and/or the driving rod and the piston rod are integrally arranged;

and/or the driving rod is coaxially arranged with the piston rod and the piston head.

8. The wafer chucking apparatus as set forth in claim 1, wherein: the fixed cylinder is detachably connected with the sucker; and/or the sucker is sleeved at the first end of the fixed cylinder;

and/or a first step structure is arranged at the first end of the fixed cylinder, a second step structure is arranged on the sucker, and the first step structure and the second step structure are matched with each other to enable the sucker and the fixed cylinder to form a connection state;

and/or the sucker comprises a sucker main body and a fixed sleeve, the fixed sleeve is fixedly connected with the sucker main body, the sucker main body is provided with the adsorption surface, an adsorption space formed by the adsorption surface is communicated with the fixed sleeve, and the second step structure is fixedly arranged on the inner wall of the fixed sleeve;

and/or the sucker main body and the fixed sleeve of the sucker are both flexible members;

and/or the adsorption surface is provided with a first area and a second area different from the first area, the first area can be in sealing contact with the wafer, and the second area is provided with an air guide port communicated with the cavity.

9. The wafer chucking apparatus as set forth in claim 1, wherein: the fixed cylinder, the piston, the elastic mechanism and the sucker are coaxially arranged.

10. A wafer transfer apparatus characterized by comprising the wafer suction apparatus according to any one of claims 1 to 9;

and/or the wafer transfer device also comprises a first driving mechanism and a second driving mechanism, wherein the first driving mechanism is in transmission connection with the piston and is at least used for exerting the external force on the piston, and the second driving mechanism is in transmission connection with the fixed cylinder and is at least used for transferring the wafer transfer device to a specified position.