Alignment structure for megasonic cleaning bonding equipment

Abstract

The utility model aims to provide the alignment structure for the megasonic cleaning bonding equipment, the high-precision alignment structure is utilized to meet the positioning precision requirement of in-situ direct bonding and realize in-situ bonding after the megasonic cleaning step of two wafers, the pollution of the cleaned wafers is avoided, the occupied space of the equipment is greatly reduced, and the production cost is reduced. The space utilization rate is improved, and the space layout cost is reduced. The alignment structure comprises a working table which can be movably arranged in an inclined mode and an objective table located on the working table, a plurality of positioning blocks are arranged on the objective table, and swing gaskets are arranged on the circumference of the objective table. A rotating module, a shaking module, an inclining module and a gasket linkage module are arranged on the side, away from the objective table, of the working table top, a plurality of dynamic actions are achieved through the modules, and therefore the purposes of multi-time alignment and high-precision alignment are achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of semiconductor manufacturing equipment especially a kind of alignment structure for megasonic cleaning bonding equipment. BACKGROUND

[0002] In current semiconductor technology, for the number of layers of stacked chips, wafer and wafer bonding is a key process, and the alignment accuracy of wafer bonding is a core parameter for measuring wafer bonding process. The commonly used bonding method in the industry is to apply centripetal pressure to the edge of the wafer for bonding. However, the process of applying centripetal force to the edge is prone to inaccurate alignment when the positioning pin pressure is insufficient or the force direction is deviated.

[0003] To solve the above problems, the industry uses a method of resisting the edge of the wafer radially to calibrate, but this calibration method relies on the motion accuracy of the positioning cylinder, so it is prone to technical defects such as low concentricity alignment accuracy and large impact of alignment action on the edge of the wafer. UTILITY MODEL CONTENT

[0004] The applicant provides an alignment structure for megasonic cleaning bonding equipment with reasonable structure, which addresses the high bonding alignment difficulty in the prior art. The alignment structure uses multiple alignment actions to improve bonding accuracy, and achieves the positioning accuracy requirement of in-situ direct bonding and the purpose of in-situ bonding after two wafers are cleaned in the megasonic cleaning step.

[0005] The technical solution adopted by the utility model is as follows:

[0006] An alignment structure for megasonic cleaning bonding equipment is used in a megasonic cleaning machine after the cleaning process. The alignment structure includes a workbench that can be tilted and moved, a carrier table located on the workbench, a plurality of positioning blocks arranged on the carrier table, and a swing gasket arranged around the carrier table.

[0007] The workbench side away from the carrier table is provided with a rotating module, a shaking module, an inclining module and a gasket linkage module,

[0008] The rotating module includes a rotating motor, which drives the carrier table to rotate,

[0009] The shaking module includes a vibration motor mounted on the workbench, and the vibration motor is independently arranged,

[0010] The inclining module uses a jacking piece, and the jacking position is eccentrically arranged with the carrier table,

[0011] The gasket linkage module includes a transmission wheel connected with the swing gasket, a driving motor driving one of the transmission wheels, and a transmission belt tensioned on all the transmission wheels.

[0012] As a further improvement of the above technical solution:

[0013] The working state of the object table includes a horizontal state, an inclined state, a shaking state and a static state.

[0014] The object table is provided with a positioning chuck, and the positioning chuck is circumferentially movably provided with a positioning block.

[0015] The shaking pads are circumferentially arranged around the object table, and each shaking pad comprises a rotating rod penetrating through the worktable surface and an extension arm connected to a top portion of the rotating rod.

[0016] The adjacent transmission wheels are provided with a tension wheel rotatably connected to the worktable surface, and the transmission belt is wound around the transmission wheels and the tension wheel.

[0017] The tension wheels are independently arranged between each other, and the relative positions of each tension wheel between the worktable surfaces are adjustable.

[0018] The vibration motor is installed at an eccentric position of the worktable surface.

[0019] The vibration motor is located at a side of the jacking member away from the hinged edge of the worktable surface.

[0020] The beneficial effects of the utility model are as follows:

[0021] The utility model has the advantages of compact and reasonable structure, convenient operation, realization of shaking action through the vibration motor installed below the worktable surface, bearing of external thrust on the wafer above the worktable surface, realization of multiple action cooperation and improvement of alignment accuracy before wafer bonding.

[0022] The technical key point of the utility model is that all the alignment structures are centrally arranged at the worktable surface, so that the floor space of the equipment is greatly reduced, the space utilization is improved, and the space layout cost is reduced.

[0023] When two wafers are placed on the object table, the worktable surface is inclined to make the two wafers displace in the same direction; the object table can be rotated to preliminarily adjust and align,

[0024] The worktable is vibrated by the vibration motor to make the object table and the wafers on the object table slightly shake, so that secondary alignment is realized.

[0025] The thrust on the two wafers of the same size is located above the worktable surface and directly applies force to the wafers. During the force applying process, the wafers simultaneously receive the thrust and the limiting reaction force of the positioning block, so that third alignment is realized.

[0026] The utility model discloses a structure is arranged to the alignment structure of megasonic cleaning bonding equipment, and the alignment bonding processing procedure of cleaning first is carried out again, because megasonic cleaning can utilize megahertz high energy sound wave, and the cleanliness is high, and the strong cavitation effect is not produced, so the subsequent alignment bonding procedure is not influenced, can directly carry out alignment, bonding after cleaning, need not have other actions such as transfer chamber, improve bonding efficiency while avoiding pollution. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is the worktable bottom structure schematic diagram of the utility model.

[0028] Figure 2 It is the structure schematic diagram of the utility model's object table and rotation motor, swing gasket.

[0029] Figure 3 It is the swing gasket synchronous transmission structure schematic diagram of the utility model.

[0030] Among them: 1, worktable surface;2, object table;3, swing gasket;4, rotation motor;5, vibration motor;6, jacking piece;

[0031] 201, positioning chuck;202, positioning block;

[0032] 301, rotation lever;302, extension arm;303, transmission wheel;304, driving motor;305, transmission belt;306, tension pulley. DETAILED DESCRIPTION

[0033] The specific implementation of the utility model will be described below in combination with the drawings.

[0034] As Figures 1-3 The utility model discloses a structure is arranged to the alignment structure of megasonic cleaning bonding equipment, and the alignment bonding processing procedure of cleaning first is carried out again, because megasonic cleaning can utilize megahertz high energy sound wave, and the cleanliness is high, and the strong cavitation effect is not produced, so the subsequent alignment bonding procedure is not influenced, can directly carry out alignment, bonding after cleaning, need not have other actions such as transfer chamber, improve bonding efficiency while avoiding pollution.

[0035] The worktable surface 1 side away from the object table 2 is provided with rotation module, shaking module, tilt module and gasket linkage module,

[0036] The rotation module includes rotation motor 4, and the rotation motor 4 drives the object table 2 to rotate,

[0037] The shaking module includes the vibration motor 5 installed on the worktable surface 1, and the vibration motor 5 is independently arranged,

[0038] The tilt module adopts jacking piece 6, and the jacking position is eccentric with the object table 2,

[0039] The gasket linkage module comprises transmission wheels 303 connected with the swing gaskets 3, a driving motor 304 driving one of the transmission wheels 303, and a transmission belt 305 tensioned on all the transmission wheels 303.

[0040] The working states of the object table 2 include a horizontal state, an inclined state, a shaking state and a static state.

[0041] The object table 2 is provided with a positioning chuck 201, and the positioning chuck 201 is circumferentially provided with positioning blocks 202.

[0042] The swing gaskets 3 are circumferentially arranged around the object table 2, and each of the swing gaskets 3 comprises a rotating rod 301 penetrating through the workbench surface 1 and an extension arm 302 connected to a top end of the rotating rod 301.

[0043] The adjacent transmission wheels 303 are provided with tension wheels 306 rotatably connected to the workbench surface 1, and the transmission belt 305 is wound around the transmission wheels 303 and the tension wheels 306.

[0044] The tension wheels 306 are independently arranged, and the relative positions of the tension wheels 306 between the workbenches are adjustable.

[0045] The vibration motor 5 is installed at an eccentric position of the workbench surface 1.

[0046] The vibration motor 5 is located at a side of the jacking member 6 away from the hinged side of the workbench surface 1.

[0047] The specific mechanism and working principle of the utility model are as follows:

[0048] As shown in Figure 1 , the square plate with holes is the workbench surface 1, and the initial state of the workbench surface 1 is the horizontal state when in use. One side of the workbench surface 1 is hinged, and the bottom surface of the other side is provided with the jacking member 6. The jacking member 6 can be a jacking cylinder, or a cam or a lead screw can be used to realize transmission jacking. In order to reduce the external force required for jacking, the jacking member 6 should be located at a position away from the hinged side of the workbench surface 1. The farther the distance between the jacking member 6 and the hinged side, the smaller the jacking force required. The closer the distance between the jacking member 6 and the hinged side, the greater the jacking difficulty, but the greater the gravity to be overcome, which can also facilitate the fine adjustment of the jacking distance. Therefore, in the embodiment, the jacking cylinder can be installed near the middle of the workbench surface 1.

[0049] Similarly, the vibration motor 5 is installed below the workbench surface 1, and the vibration motor 5 is used to drive the workbench surface 1 to vibrate, and at the same time, the object table 2 and the wafer slightly shake, so that the two wafers are further aligned. The vibration motor 5 can be installed at an eccentric position of the workbench surface 1 to prevent the vibration amplitude of the object table 2 from being too large.

[0050] The worktable 2 can rotate by itself. The rotation principle is that the rotation motor 4 located below the worktable 1 drives the worktable 2 to rotate, and the purpose of the rotation of the worktable 2 is also to align the two wafers. The positioning chuck 201 and the positioning block 202 are arranged on the worktable surface of the worktable 2, and are used for preliminarily positioning the wafer below. The wafer above is aligned by tilting, shaking and rotating. The two wafers are separated by the swing pad 3. In order to enable all the swing pads 3 to move synchronously and prevent the precision of the wafer which has been aligned from being affected, a linkage structure is arranged below the worktable 1 to drive all the swing pads 3.

[0051] As shown in Figure 2 , each swing pad 3 comprises a rotating rod 301 penetrating through the worktable 1, and a transmission wheel 303 connected to the bottom of the rotating rod 301. In the embodiment, three swing pads 3 are adopted, and three rotating rods are arranged on the worktable 1 in a circumferential array around the worktable 2. A tension wheel 306 is arranged between two adjacent transmission wheels 303, and the tension wheel 306 is adjustably and tightly mounted in a designated position through a waist-shaped groove. Figure 1 and Figure 3 As shown, the transmission belt 305 is sequentially wound around the tension wheel 306 and the transmission wheel 303 to form a loop, and a driving motor 304 is provided as a power source for one of the transmission wheels 303 to drive all the transmission wheels 303 to synchronously transmit; at the same time, the rotating rod and the extension arm 302 in Figure 2 are driven to rotate, so that the movement path of the extension arm 302 passes through and separates from the two wafers.

[0052] In use, the wafer is calibrated multiple times.

[0053] The utility model is applied to megasonic cleaning equipment, and the megasonic cleaning equipment belongs to the prior art, which is not described in detail in the embodiment. The improvement point is that the conventional worktable 2 in the megasonic cleaning equipment is transformed into a multi-action alignment worktable 2.

[0054] Among the two wafers cleaned, the lower wafer falls onto the worktable 2 and is preliminarily positioned by the positioning chuck 201 and the positioning block 202; then the driving motor 304 drives all the rotating rods 301 to rotate, and the swing pad 3 is rotated to above the circumference of the lower wafer, and then the upper wafer is placed, at this time, the jacking piece 6 is started, the worktable 1 is slightly tilted, and the two wafers which have not contacted are tilted and slid to complete the first calibration.

[0055] The rotating cylinder rotates to drive the wafer to rotate, and the vibrating cylinder drives the wafer to shake, and the tilting, rotating and shaking are simultaneously performed. The gravity of the wafer is utilized to make the wafer positioning edge perfectly fit the positioning block 202, so as to reduce the dislocation and scratches caused in the process of placing the wafer. Figure 2 In the figure, the pushing force F which can be applied to the wafer is also shown, and is used for auxiliary positioning.

[0056] The alignment structure is particularly suitable for use in a megasonic cleaning bonding device.

[0057] The megasonic cleaning does not cause strong cavitation effect, and can avoid damage to the surface of the cleaning object and residual pollutants in the cleaning process. The megasonic cleaning has high efficiency, short time, and uses deionized water for cleaning, so that the harm level to the environment is very low. The traditional mechanical alignment method applies centripetal pressure to the edge of the wafer, and a larger impact force may cause a risk of fragmentation, and the concentric calibration accuracy of the wafer is limited by the mechanical expansion and contraction member, and is always low. In the current related reports, the structure of the mechanical expansion and contraction member and the image recognition means are increased to improve the concentricity of the two bonded wafers, but the shape and position of the limiting groove are not optimized. Based on this, the utility model provides a structure design of an arc-shaped limiting groove push rod, which increases the effective contact area of the limiting groove and the two wafers, can not only increase the buffer, but also improve the positioning accuracy, and combines a spring device to compensate for the positioning error of the extension rod driven by the air cylinder against the wafer, in order to further improve the positioning accuracy, an inclined shaking device is used to reduce the misplacement and scratching of the two wafers, so as to improve the bonding quality. The wafers after cleaning and alignment are directly bonded in situ, which avoids the pollution of the wafers after cleaning, greatly reduces the floor space of the equipment, improves the space utilization rate, and reduces the space layout cost.

[0058] The above description is an explanation of the utility model, not a limitation of the utility model, the range defined by the utility model is referred to the claims, within the protection range of the utility model, any form of modification can be made.

Claims

1. An alignment structure for a mega-sound cleaning and bonding device, characterized in that: Used in the cleaning process of a Megasonic cleaning machine; the alignment structure includes a tiltable and movable worktable (1), a platform (2) located on the worktable (1), a number of positioning blocks (202) on the platform (2), and swing pads (3) on the circumference of the platform (2). The worktable (1) is equipped with a rotation module, a shaking module, a tilting module, and a pad linkage module on the side facing away from the platform (2). The rotation module includes a rotation motor (4), which drives the platform (2) to rotate. The vibration module includes a vibration motor (5) mounted on the workbench (1), and the vibration motor (5) is independently configured. The tilting module uses a lifting component (6), and the lifting position is eccentrically set with respect to the platform (2). The pad linkage module includes a transmission wheel (303) connected to the swing pad (3), an active motor (304) that drives one of the transmission wheels (303), and a transmission belt (305) tensioned on all the transmission wheels (303).

2. The alignment structure for a mega-acoustic cleaning and bonding apparatus as described in claim 1, characterized in that: The working states of the stage (2) include horizontal state, tilted state, shaking state, and stationary state.

3. The alignment structure for a mega-acoustic cleaning and bonding apparatus as described in claim 1, characterized in that: A positioning suction cup (201) is provided on the stage (2), and a positioning block (202) is provided on the circumference of the positioning suction cup (201).

4. The alignment structure for a mega-acoustic cleaning and bonding apparatus as described in claim 1, characterized in that: The oscillating pads (3) are arranged in a circular array around the stage (2). The oscillating pads (3) include a rotating rod (301) that passes through the worktable surface (1) and an extension arm (302) connected to the top of the rotating rod (301). The transmission wheel (303) is coaxially arranged at one end of the rotating rod (301) away from the extension arm (302).

5. The alignment structure for a mega-acoustic cleaning and bonding apparatus as described in claim 4, characterized in that: A tensioning wheel (306) is provided between adjacent transmission wheels (303) and is rotatably connected to the worktable (1). The transmission belt (305) passes around the transmission wheel (303) and the tensioning wheel (306).

6. The alignment structure for a mega-acoustic cleaning and bonding apparatus as described in claim 5, characterized in that: The tensioning rollers (306) are set independently of each other, and the relative position of each tensioning roller (306) to the worktable is adjustable.

7. The alignment structure for a mega-acoustic cleaning and bonding apparatus as described in claim 1, characterized in that: The vibratory motor (5) is installed at an eccentric position on the worktable (1).

8. The alignment structure for a mega-acoustic cleaning and bonding apparatus as described in claim 1, characterized in that: The vibratory motor (5) is located on the side of the lifting component (6) away from the hinged edge of the worktable surface (1).

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