Wafer suction cup and wafer bonding equipment
By designing adsorption areas, extraction areas, and sealing rings on the wafer chuck, and using a vacuum source to create a negative pressure environment, the quality defects of wafer bonding under atmospheric conditions are solved, and efficient wafer bonding is achieved.
Patent Information
- Application Number
- CN202423321983.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2026-02-06
- Estimated Expiration
- 2034-12-31
AI Technical Summary
When bonding in an atmospheric environment, existing wafer chucks cannot guarantee the vacuum level near the wafer, resulting in bonding quality defects such as bonding voids and weak bonding forces.
Design a wafer chuck with an adsorption area, an air extraction area, and a sealing ring. It is connected to a vacuum source through a first air channel and a second air channel to form a negative pressure environment, ensuring that the wafer completes bonding in a sealed space.
It improves bonding strength and bonding yield, reduces voids during bonding, and has extremely high vacuum building efficiency.
Smart Images
Figure CN223885624U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of sucking disc, specifically, relates to a wafer sucking disc and wafer bonding equipment. BACKGROUND
[0002] In the field of semiconductor, wafer bonding is through physical or chemical method to paste wafer. In the wafer bonding process, wafer needs to be fixed to ensure that wafer does not slide and does not warp in the processing. The common way is to use vacuum to adsorb wafer on sucking disc or use limiting device to fix wafer.
[0003] In the prior art, high-precision hybrid bonding is limited by high-precision alignment bonding platform, and the whole high-precision bonding system cannot be processed in vacuum environment, so the bonding process is usually carried out in atmospheric environment. However, the existing wafer sucking disc generally opens holes or grooves on the supporting plane, and the wafer is adsorbed after vacuum, which causes the wafer to contact the atmosphere when bonding in the atmospheric environment, and it is difficult to ensure the vacuum degree near the wafer, and further, the wafer is prone to bonding quality defects, such as bonding cavity and weak bonding force. UTILITY MODEL CONTENT
[0004] The utility model aims at providing a wafer sucking disc and wafer bonding equipment to alleviate the technical problem that the existing wafer sucking disc is prone to cause wafer bonding quality defects.
[0005] The wafer sucking disc provided by the utility model has a bearing surface provided with an adsorption area, an air extraction area and a sealing ring, the adsorption area is used for adsorbing wafer, the sealing ring is arranged around the adsorption area, and the air extraction area is located between the sealing ring and the adsorption area.
[0006] The adsorption area is provided with a first air duct, the air extraction area is provided with a second air duct, and the first air duct and the second air duct are used for connecting vacuum air sources; the sealing rings of two wafer sucking discs are butted, and a closed space can be formed on the inner side of the sealing ring.
[0007] Preferably, as an implementable mode, the first air duct and the second air duct are used for connecting two vacuum air sources respectively.
[0008] Preferably, as an implementable mode, the second air duct includes a first annular groove arranged around the adsorption area.
[0009] Preferably, as an implementable mode, the sealing ring is a soft sealing ring or a hard sealing ring.
[0010] Preferably, as an implementable mode, the material of the sealing ring is rubber.
[0011] Or, the material of the sealing ring is the same as the material of the chuck body of the wafer chuck.
[0012] Preferably, as an implementable mode, the sealing ring is arranged at the edge of the wafer chuck, or the sealing ring is arranged close to the edge of the wafer chuck.
[0013] Preferably, as an implementable mode, the first air channel comprises a plurality of second annular grooves and a strip-shaped groove communicating each of the second annular grooves.
[0014] Or, the adsorption area comprises an annular boss and a plurality of support protrusions, the top of the annular boss is coplanar with the top of the support protrusions, and the first air channel comprises a recess structure between the annular boss and the plurality of support protrusions.
[0015] Preferably, as an implementable mode, the wafer chuck is provided with a first gas hole and a second gas hole, one end of the first gas hole is communicated with the adsorption area, and the other end is communicated with a vacuum air source; one end of the second gas hole is communicated with the pumping area, and the other end is communicated with a vacuum air source.
[0016] Preferably, as an implementable mode, the first gas hole and the second gas hole are in multiple groups, and the multiple groups of the first gas hole and the multiple groups of the second gas hole are uniformly arranged around the center of the wafer chuck.
[0017] The wafer bonding device provided by the utility model comprises a driving mechanism and a wafer chuck.
[0018] The sealing rings of the two wafer chucks are oppositely arranged, the driving mechanism is connected with the wafer chucks, and is used for driving the wafer chucks to move in the direction perpendicular to the bearing surface.
[0019] Compared with the prior art, the utility model has the beneficial effects that:
[0020] Before bonding, the first air passage can be vacuumed by a vacuum air source to form a negative pressure environment in the adsorption area, so that the wafers to be bonded can be fixed and attached to the bearing surface of the wafer chuck by vacuum adsorption force; after the adsorption and fixation of the two wafers to be bonded are completed, the two wafer chucks can be moved close to each other, so that the two wafers to be bonded are attached together, and the sealing ring of the wafer chuck adsorbing the two wafers to be bonded can be docked, at this time, a closed space is formed on the inner side of the sealing ring, and the two wafers to be bonded are in the closed space; the second air passage can be vacuumed by the vacuum air source to form a negative pressure environment in the closed space, so that the closed space where the wafers to be bonded are located can be isolated from the atmosphere, and the vacuum air source can also timely remove the gas discharged during wafer bonding through the second air passage, so that the wafer can complete bonding under negative pressure environment. The vacuum pressure of the second air passage is lower than that of the first air passage, which can not only ensure that the wafer can be stably adsorbed on the adsorption area of the wafer chuck, but also provide a negative pressure environment lower than the atmospheric pressure for the bonding environment.
[0021] Therefore, the wafer chuck provided by the utility model not only can fix the wafer, but also can establish a negative pressure environment in the closed space where the wafer is located, so that the wafer can complete bonding under negative pressure environment, the air holes generated during wafer bonding can be reduced, and the bonding force and the bonding yield can be improved; in addition, the second air passage has a small volume and a high vacuum establishment efficiency.
[0022] The wafer bonding equipment provided by the utility model comprises the wafer chuck, and has all the advantages of the wafer chuck. BRIEF DESCRIPTION OF DRAWINGS
[0023] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description, and obviously, the drawings in the following description are only the embodiments of the utility model, and those skilled in the art can also obtain other drawings according to the provided drawings without creating any creative labor.
[0024] Figure 1 The working principle schematic diagram of the wafer chuck provided by the embodiment of the utility model is shown in the figure.
[0025] Figure 2 The working principle schematic diagram of the wafer chuck provided by the embodiment of the utility model is shown in the figure.
[0026] Figure 3 The working principle schematic diagram of the wafer chuck provided by the embodiment of the utility model is shown in the figure.
[0027] EXPLANATION OF REFERENCE NUMERALS:
[0028] 100 - wafer chuck; 110 - sealing ring; 120 - first annular groove; 130 - second annular groove; 140 - strip-shaped groove; 150 - annular boss; 160 - supporting bump; 170 - first air hole; 180 - second air hole;
[0029] 200 - wafer;
[0030] 300 - vacuum air source. DETAILED DESCRIPTION
[0031] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0032] The present application will be described in further detail below through specific examples and in conjunction with the drawings.
[0033] Referring to Figures 1-3 The present embodiment provides a wafer chuck 100, a bearing surface of the wafer chuck 100 is provided with an adsorption area, a pumping area and a sealing ring 110, the adsorption area is used for adsorbing a wafer 200, the sealing ring 110 is arranged around the adsorption area, and the pumping area is located between the sealing ring 110 and the adsorption area; the adsorption area is provided with a first air duct, the pumping area is provided with a second air duct, and the first air duct and the second air duct are both used for connecting a vacuum air source 300; the sealing rings 110 of two wafer chucks 100 are butted, and a closed space can be formed on the inner side of the sealing ring 110.
[0034] Before the bonding, the first air passage can be vacuumed by the vacuum air source 300 to form a negative pressure environment in the adsorption area, so that the wafer 200 to be bonded can be fixed to the bearing surface of the wafer chuck 100 by vacuum adsorption; after the adsorption and fixation of the two wafers 200 to be bonded are completed, the two wafer chucks 100 can be moved close to each other, so that the two wafers 200 to be bonded can be attached together, and the sealing ring 110 of the wafer chuck 100 adsorbing the two wafers 200 to be bonded can be docked at the same time. At this time, a closed space will be formed on the inner side of the sealing ring 110, and the two wafers 200 to be bonded are located in the closed space. The second air passage can be vacuumed by the vacuum air source 300 to form a negative pressure environment in the closed space, so that the closed space where the wafer 200 to be bonded is located can be isolated from the atmosphere, and the vacuum air source 300 can also timely remove the gas discharged during the wafer bonding process through the second air passage, so that the wafer 200 can complete the bonding under a negative pressure environment. The vacuum pressure of the second air passage is lower than that of the first air passage, which can not only ensure that the wafer 200 can be stably adsorbed on the adsorption area of the wafer chuck 100, but also provide a negative pressure environment lower than the atmospheric pressure for the bonding environment.
[0035] Therefore, the wafer chuck 100 provided by the embodiment can not only fix the wafer 200, but also establish a negative pressure environment in the closed space where the wafer 200 is located, so that the wafer 200 can complete the bonding under a negative pressure environment, which can reduce the voids generated during the bonding of the wafer 200, improve the bonding force and the bonding yield. In addition, the second air passage has a small volume and high vacuum establishment efficiency.
[0036] Preferably, the first air passage and the second air passage can be respectively communicated with two vacuum air sources 300, so that the two vacuum air sources 300 can be controlled respectively to vacuumize the first air passage and the second air passage, which can avoid cross talk between the air passages. Of course, the first air passage and the second air passage can also be communicated with the same vacuum air source 300, in which case, the vacuum pressure of the second air passage needs to be set lower than that of the first air passage.
[0037] The second air passage can include a first annular groove 120 arranged around the adsorption area, so that the adsorption area can be surrounded by a negative pressure environment, which can improve the uniformity of the vacuum distribution around the wafer 200, further reduce the voids generated during the bonding of the wafer 200, and improve the bonding force and the bonding yield.
[0038] As an implementable manner, the sealing ring 110 can be a soft sealing ring, so that when the two sealing rings 110 are docked, adaptive deformation can occur according to the actual situation, so that the two wafers 200 to be bonded can be attached to each other, and the two sealing rings 110 can be in close contact, thereby obtaining a good sealing effect and maintaining a good vacuum environment in the second air passage.
[0039] Specifically, the sealing ring 110 can be made of rubber, for example, made of silicone rubber or fluororubber, so as to have deformability and ensure sealing performance.
[0040] As another implementation, the sealing ring 110 can be a hard sealing ring, which only needs to ensure the manufacturing precision of the structure.
[0041] Specifically, the sealing ring 110 can be made of the same material as the chuck body of the wafer chuck 100, which is convenient for manufacturing. In this case, the wafer chuck 100 can be an integrated structure.
[0042] Preferably, referring to Figure 2 and Figure 3 , the sealing ring 110 can be arranged at the edge of the wafer chuck 100 to fully utilize the wafer chuck 100. Of course, referring to Figure 1 , the sealing ring 110 can also be arranged close to the edge of the wafer chuck 100.
[0043] The above-mentioned adsorption area can be any one of the following two structures:
[0044] First, referring to Figure 2 , the first air channel can include a plurality of second annular grooves 130 and a strip-shaped groove 140 connected to each of the second annular grooves 130, so that the first air channel is an integral through air channel. Thus, the vacuum pressures of each part of the first air channel tend to be consistent, which can improve the uniformity of the adsorption force received by each part of the wafer 200 and improve the adsorption effect.
[0045] Second, referring to Figure 3 , an annular boss 150 and a plurality of support bumps 160 can be arranged in the adsorption area, the top of the annular boss 150 and the top of the support bumps 160 are arranged in the same plane, and the recess structure between the annular boss 150 and the plurality of support bumps 160 is used as the first air channel. The first air channel is also an integral through air channel, which has a better adsorption effect.
[0046] A first air hole 170 and a second air hole 180 can be arranged on the wafer chuck 100. One end of the first air hole 170 is connected to the adsorption area, and the other end is connected to the vacuum air source 300. One end of the second air hole 180 is connected to the pumping area, and the other end is connected to the vacuum air source 300, which is convenient for structural layout.
[0047] Specifically, the first gas holes 170 and the second gas holes 180 can be arranged in multiple groups, and the multiple groups of the first gas holes 170 are arranged uniformly around the center of the wafer chuck 100, and the multiple groups of the second gas holes 180 are arranged uniformly around the center of the wafer chuck 100, so that the uniformity of the vacuum distribution in the first gas channel and the uniformity of the vacuum distribution in the second gas channel can be improved.
[0048] Each group of the first gas holes 170 can include multiple first gas holes 170, and the multiple first gas holes 170 in the same group can be arranged at intervals along the radial direction of the wafer chuck 100.
[0049] Each group of the second gas holes 180 can include one second gas hole 180.
[0050] The embodiment also provides a wafer bonding device, which includes the wafer chuck 100 and a driving mechanism; the sealing rings 110 of the two wafer chucks 100 are arranged oppositely, and the driving mechanism is connected with the wafer chucks 100 and used for driving the wafer chucks 100 to move in a direction perpendicular to the bearing surface.
[0051] When bonding of two wafers 200 is needed, after the two wafers 200 are respectively adsorbed and fixed to the adsorption areas of the two wafer chucks 100, the driving mechanism is controlled to drive the wafer chucks 100 to move in a direction perpendicular to the bearing surface and towards the bearing surface, so that the two wafers 200 are close to each other, and the bonding is realized.
[0052] The wafer bonding device provided by the embodiment has all the advantages of the wafer chuck 100, can reduce the voids generated during bonding of the wafers 200, improve the bonding force and the bonding yield, and has a very high vacuum establishment efficiency.
[0053] The driving mechanism can be selected to drive one of the wafer chucks 100 to move, or can be selected to drive the two wafer chucks 100 to move respectively.
[0054] In the description of the utility model, it is necessary to explain that, unless there is definite stipulation and limitation, the term 'connection' should be understood broadly, for example, it can be fixed connection, also can be detachable connection, or integrally connected, can be mechanical connection, also can be electrical connection, can be direct connection, also can pass through intermediate medium indirectly connect, can be two element inside intercommunication, for ordinary skilled in the art, the specific meaning of the above-mentioned term in the utility model can be understood according to specific circumstances.
[0055] Finally, it should be noted that: the above embodiments are used to illustrate the technical solutions of the present application, but not limited to them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A wafer chuck, characterized by, The carrying surface of the wafer chuck (100) is provided with an adsorption area for adsorbing a wafer (200), a sealing ring (110) arranged around the adsorption area, and a pumping area between the sealing ring (110) and the adsorption area. The adsorption area is provided with a first air channel, and the pumping area is provided with a second air channel, both of which are used to communicate with a vacuum air source (300).
2. The wafer chuck of claim 1, wherein The first air channel and the second air channel are respectively used to communicate with two vacuum air sources (300).
3. The wafer chuck of claim 1, wherein The second air channel includes a first annular groove (120) arranged around the adsorption area.
4. The wafer chuck of claim 1, wherein The sealing ring (110) is a soft sealing ring or a hard sealing ring.
5. The wafer chuck of claim 4, wherein, The material of the sealing ring (110) is rubber. Alternatively, the material of the sealing ring (110) is the same as that of the chuck body of the wafer chuck (100).
6. The wafer chuck of claim 1, wherein The sealing ring (110) is arranged at the edge of the wafer chuck (100), or is arranged close to the edge of the wafer chuck (100).
7. The wafer chuck of claim 1, wherein The first air channel includes a plurality of second annular grooves (130) and a strip-shaped groove (140) communicating with each of the second annular grooves (130). Alternatively, the adsorption area includes an annular boss (150) and a plurality of support protrusions (160), the top of the annular boss (150) is coplanar with the top of the support protrusion (160), and the first air channel includes a recess structure between the annular boss (150) and the plurality of support protrusions (160).
8. The wafer chuck of any of claims 1-7, wherein, The wafer chuck (100) is provided with a first air hole (170) and a second air hole (180), one end of the first air hole (170) communicates with the adsorption area, and the other end communicates with a vacuum air source (300); one end of the second air hole (180) communicates with the pumping area, and the other end communicates with a vacuum air source (300).
9. The wafer chuck of claim 8, wherein, The first air hole (170) and the second air hole (180) are multiple groups, and the multiple groups of the first air hole (170) and the multiple groups of the second air hole (180) are uniformly arranged around the center of the wafer chuck (100).
10. A wafer bonding apparatus, characterized by comprising: The drive mechanism and two wafer chucks (100) according to any one of claims 1-9 are included. The sealing rings (110) of the two wafer chucks (100) are oppositely arranged, the drive mechanism is connected with the wafer chucks (100), and is used to drive the wafer chucks (100) to move in a direction perpendicular to the carrying surface.