CN115070604B - Double-sided grinding device and double-sided grinding method - Google Patents

Abstract

The present disclosure relates to a double-sided lapping device, comprising: the annular bearing piece comprises a shell, a bearing ring and a driving piece, wherein the driving piece is arranged on the bearing ring and used for clamping a positioning groove of a wafer; two static pressure plates symmetrically arranged on two sides of the annular bearing piece respectively; two grinding wheels respectively symmetrically arranged at two sides of the annular bearing piece; the air-sensitive reaction unit comprises an air-sensitive induction area and an air injection area which are respectively arranged on the two static plates in a corresponding manner, and the air-sensitive induction area and the air injection area are positioned so that the position of the positioning groove can be determined by the induction of air injection from the air injection area by the air-sensitive induction area; and the control unit can control the annular bearing piece to rotate based on the position of the positioning groove so as to drive the driving piece to reach the position corresponding to the positioning groove. The disclosure also relates to a double-sided lapping method using the double-sided lapping device. In the double-sided grinding device, better clamping of the driving piece and the positioning groove can be realized.

Description

Double-sided grinding device and double-sided grinding method

Technical field

The present disclosure relates to the technical field of grinding devices, and in particular, to a double-sided grinding device and a double-sided grinding method utilizing the double-sided grinding device.

Background technique

With the development of semiconductor technology, the diameter of silicon wafers is getting larger and larger, while the feature sizes of integrated circuits are getting smaller and smaller. As a result, higher requirements are placed on the flatness and removal rate of the wafer surface. Double-sided grinding is one of the most effective technical means to speed up the surface removal rate and improve the flatness of the wafer surface.

For the double-sided grinding process, the carrier used to carry the wafer is its core component. The wafers are positioned before entering the grinding chamber, and are then picked up and moved into the grinding chamber by a robotic arm. However, when there is a deviation in the position of the previous positioning, if the deviation is small, it will take a long time for the equipment to confirm and start the grinding process, and the quality of the processed wafer may be abnormal. At least the wafer will be scrapped, and at worst, it will be processed. When debris breaks into the grinding wheel, etc., resulting in greater cost losses; if the deviation is large, the equipment will directly alarm and shut down, seriously affecting production capacity.

On the other hand, the driving piece of the carrier used to engage with the positioning groove of the wafer is not adjustable. During the continuous processing, the protruding part of the driver plate used to engage with the positioning groove of the wafer is worn due to constant contact with the wafer, extrusion and collision, resulting in an increasing gap between the wafer and the driver plate. The larger the wafer is, the more it will cause the wafer to shake violently during processing, causing edge chipping or even fragmentation, leading to equipment alarms, etc.

Contents of the invention

This section provides a general summary of the disclosure and is not a comprehensive disclosure of the full scope or all features of the disclosure.

An object of the present disclosure is to provide a double-sided grinding device that can achieve optimal engagement between the driving plate and the positioning groove of the wafer.

Another object of the present disclosure is to provide a double-sided grinding device that can reduce the frequency of replacement and maintenance of the driving plate and thus increase the productivity of the equipment.

In order to achieve one or more of the above objects, according to an aspect of the present disclosure, a double-sided grinding device is provided, which may include:

An annular carrier, which includes a housing, a carrier ring provided on the inner peripheral side of the housing for supporting the outer peripheral side of the wafer to be processed in the radial direction, and a positioning recess provided on the carrier ring for catching the wafer to be processed. Slotted drive piece;

Two static pressure plates, the two static pressure plates are symmetrically arranged on both sides of the annular bearing member;

Two grinding wheels, the two grinding wheels are symmetrically arranged on both sides of the annular bearing member;

A gas-sensitive sensor unit, which includes a gas-jet zone and a gas-sensitive zone respectively arranged on the two static pressure plates in a corresponding manner. The gas-jet zone and the gas-sensitive zone are positioned so as to be able to detect the gas from the gas-jet zone through the gas-sensitive zone. The induction of air jet to determine the position of the positioning groove of the wafer to be processed; and

The control unit is capable of controlling the rotation of the annular carrier based on the determined position of the positioning groove to drive the driving piece to a position corresponding to the positioning groove.

In the above double-sided grinding device, the driving piece may be movable relative to the carrying ring, and the control unit can control the driving piece to move relative to the carrying ring based on the determined position of the positioning groove to adjust the position of the driving piece. Adjustment.

In the above double-sided grinding device, the movement of the driving piece may be movement along the radial direction and/or the circumferential direction of the annular carrier.

In the above double-sided grinding device, the movement of the driving piece can be realized through a central shaft connected to the driving piece. The central shaft can reciprocate along the radial direction of the annular bearing member to drive the driving piece to move in the radial direction.

In the above-mentioned double-sided grinding device, the movement of the driving piece can also be realized by an angle adjustment assembly. The angle adjustment assembly includes a rotating member provided on the central axis that can rotate clockwise and counterclockwise, and a rotating member fixedly provided on the driving piece and A transmission member engaged with the rotating member, wherein the angle adjustment assembly is configured to move the transmission member engaged with the rotating member along the circumferential direction of the annular carrier through clockwise and counterclockwise rotation of the rotating member, thereby driving the driving piece along the Movement in circumferential direction.

In the above double-sided grinding device, the driving piece can be made of high-strength and high-toughness alloy.

In the above-mentioned double-sided grinding device, the surface of the protruding portion of the driving piece for engaging with the positioning groove may be plated with a wear-resistant layer.

In the above double-sided grinding device, the driving piece may be provided with a buffer hole for stress relief.

In the above double-sided grinding device, the outer shell of the annular carrier may be made of a low-expansion alloy.

According to another aspect of the present disclosure, a double-sided grinding method is provided. The double-sided grinding method is performed using the double-sided grinding device according to any of the preceding paragraphs. The double-sided grinding method includes:

Load the wafer to be processed into the annular carrier by engaging the driving piece with the positioning groove of the wafer to be processed;

The wafer to be processed is kept balanced by the gas injected from the air holes respectively provided on the two static pressure plates; and

Two grinding wheels grind the opposite sides of the wafer to be processed.

According to the present disclosure, the positioning of the driving piece and the wafer is found by arranging a gas-sensitive sensing unit to locate the position of the positioning groove of the wafer to be processed and adjusting the position of the driving piece based on the obtained accurate position of the positioning groove. The best snap position for the groove. As a result, better engagement between the driver piece and the wafer positioning groove can be achieved, thereby effectively avoiding problems such as abnormal wafer quality and equipment alarm downtime caused by loading position deviations.

The above features and advantages and other features and advantages of the present disclosure will be more apparent from the following detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings.

Description of the drawings

1 is a side view of a double-sided grinding device according to an embodiment of the present disclosure, showing the positional relationship of an annular bearing member relative to a static pressure plate and a grinding wheel;

Figure 2 schematically shows the grinding wheel of the double-sided grinding device in Figure 1;

3 shows a side view of a gas-sensitive sensing unit of a double-sided grinding device in an operating state according to an embodiment of the present disclosure;

4 illustrates a gas-sensitive sensing unit of a double-sided grinding device according to an embodiment of the present disclosure in a front view;

Figure 5 shows an annular carrier in a front view according to an embodiment of the present disclosure;

6 schematically illustrates the matching positioning process of the driving piece and the positioning groove of the wafer by the gas sensing unit according to an embodiment of the present disclosure; and

7 illustrates a driver blade according to an embodiment of the present disclosure in a front view.

Detailed ways

The present disclosure is described in detail below with the aid of exemplary embodiments with reference to the accompanying drawings. It should be noted that the following detailed description of the present disclosure is for illustrative purposes only and is in no way limiting of the present disclosure. Furthermore, the same reference numerals are used in the various drawings to designate the same components.

Referring to Figures 1 and 3, a double-sided grinding device 1 according to an embodiment of the present disclosure is shown, which includes:

Ring-shaped carrier 11, which is used to carry the wafer to be processed;

Two static pressure plates 12, 13, these two static pressure plates 12, 13 are respectively symmetrically arranged on both sides of the annular bearing member 11; and

Two grinding wheels 14 and 15 are respectively symmetrically arranged on both sides of the annular bearing member 11 .

As shown in FIG. 5 , the annular carrier 11 includes a housing 111 , a carrier ring 112 provided on the inner peripheral side of the housing 111 for radially supporting the outer peripheral side of the wafer to be processed, and a carrier ring 112 provided on the inner peripheral side of the housing 111 . The driving piece 113 is used to engage the positioning groove 31 (see Figure 6) of the wafer to be processed.

When the wafer is loaded into the annular carrier 11, the driving piece 113 of the annular carrier 11 is engaged in the positioning groove of the wafer. Therefore, during the double-sided grinding process, the driving piece 113 of the annular carrier 11 is The rotation can drive the wafer to rotate synchronously through the engagement between the driving piece 113 and the positioning groove, so that the wafer can be ground from both sides by the grinding wheel fed in a rotational manner.

The static pressure plates 12 and 13 are respectively provided with a plurality of air holes 121 and 131 on their surfaces for injecting gas to opposite sides of the wafer after the wafer is loaded on the annular carrier 11, so that the wafer can maintain balance. The static pressure plates 12, 13 are also provided with through holes at their lower portions to allow the grinding wheel to be fed through the through holes when grinding and to exit through the through holes in the opposite direction when grinding is stopped.

As shown in Figure 2, the grinding wheels 14 and 15 have a metal base and a plurality of abrasive grains spaced apart on the metal base. When grinding, the grinding wheels 14 and 15 are fed in the direction of the annular carrier 11 through the through holes of the static pressure plates 12 and 13 to grind the opposite sides of the wafer to be processed from both sides.

Usually, the wafer to be processed is pre-positioned before entering the grinding chamber, and is then moved into the grinding chamber by, for example, a robotic arm to be loaded on an annular carrier. However, the loading position may be skewed, causing problems in wafer processing. In the present disclosure, the positioning of the driving piece and the wafer is achieved by first positioning the position of the positioning groove of the wafer to be processed during loading and then adjusting the position of the driving piece based on the obtained accurate position of the positioning groove. Optimal snap fit into the groove.

In order to achieve the above-mentioned accurate positioning of the position of the positioning groove, according to an embodiment of the present disclosure, with reference to FIGS. 3 and 4 , the double-sided grinding device 1 further includes a gas-sensitive sensing unit. The gas-sensitive sensing unit includes a gas-sensitive sensing area 161 and a gas-jet area 162 respectively arranged on the two static pressure plates 12 and 13 in a corresponding manner. The area 161 senses the air jet from the air jet area 162 to determine the position of the positioning groove of the wafer to be processed.

Specifically, the gas-sensitive sensing area 161 and the air jet area 162 are respectively arranged at edge portions of the surfaces of the static pressure plates 12 and 13 and correspond in position, so that the gas-sensitive sensing area 161 can sense the air jet from the air jet area 162 . It can be understood that the gas sensing area 161 and the air injection area 162 can also be provided on the surfaces of the static pressure plates 13 and 12 respectively.

As can be clearly observed in FIG. 4 , the air injection area 162 may include a plurality of air injection holes (shown as hollow dots), and the gas-sensitive sensing area 161 may include a plurality of sensors corresponding one-to-one to the plurality of air injection holes. area (shown as solid dots).

As shown in FIG. 6 , the gas sensing area 161 and the ejection area 162 are positioned to roughly correspond to the contact area of the carrier ring 112 with the wafer to be processed, and due to the aforementioned pre-positioning, the positions of the driving piece and the positioning groove It is also roughly located near the corresponding range of the gas sensing area 161 and the jet area 162 . When the jet area 162 jets towards the wafer through the jet hole, the air flow will be jetted to the circumferential edge of the wafer. At the positioning groove located at the circumferential edge of the wafer, the air flow will be unblocked and reach the gas sensor in greater amounts. Zone 161 is thus sensed by it. Thus, the position of the positioning groove of the wafer to be processed can be accurately determined.

The double-sided grinding device 1 also includes a control unit (not shown), which can control the rotation of the annular carrier 11 based on the determined position of the positioning groove to drive the driving piece 113 to a position corresponding to the positioning groove. .

Specifically, the sensing signal characterizing the position of the positioning groove of the wafer to be processed can be transmitted to the control unit, and then the control unit can control the annular carrier 11 to perform a small rotation based on the sensing signal, and thereby drive the The driving piece 113 rotates slightly to reach a position corresponding to the positioning groove to achieve better clamping.

Through the above structure and method, better engagement between the driver plate and the wafer positioning groove can be achieved, thereby effectively avoiding problems such as abnormal wafer quality and equipment alarm downtime caused by deviations in the loading position.

Referring to FIGS. 6 and 7 , in the present disclosure, the engagement between the driving piece and the positioning groove can be further improved by configuring the driving piece 113 to be movable by itself.

To this end, in the embodiment of the present disclosure, the driving piece 113 is configured to be movable relative to the carrying ring 112, and the control unit can control the driving piece 113 relative to the carrying ring 112 based on the determined position of the positioning groove. Move to adjust the above-mentioned position of the driving piece 113, that is, the position corresponding to the positioning groove.

Through the movement of the driving piece 113 itself, the position of the driving piece 113 can be controlled more flexibly and accurately, so that the driving piece 113 can find the best engaging position with the positioning groove of the wafer, thereby effectively avoiding the problem of the driving piece 113 The position is fixed, and constant collision and wear during continuous processing lead to the increasing gap between it (mainly its protruding part) and the positioning groove of the wafer, causing abnormal wafer quality problems, which greatly reduces edge chipping and debris. The occurrence of this situation effectively saves production costs and further ensures the stability of the processing process.

It is conceivable that the above-mentioned movement of the driving piece 113 may be a movement in the radial direction and/or the circumferential direction of the annular carrier 11 .

Specifically, as shown in Figure 6, by moving the driving piece 113 along the radial direction of the annular carrier 11, the size of the gap in the radial direction between the driving piece 113 and the positioning groove can be adjusted; And by moving the driving piece 113 along the circumferential direction of the annular carrier 11, the size of the gap in the circumferential direction between the driving piece 113 and the positioning groove can be adjusted, thereby further finding the distance between the driving piece 113 and the positioning groove. Locate the groove in the best snap position.

It can be understood that the driving piece 113 can only perform one of the movement in the radial direction and the circumferential direction, or both, depending on the current alignment of the driving piece 113 and the positioning groove. Condition.

It is conceivable that since the adjustment of the driving piece 113 is small, the movement of the driving piece 113 in the circumferential direction may be substantially replaced by its movement in a direction perpendicular to the radial direction. This can make the movement of the driving piece 113 simpler.

Below, an exemplary implementation of the driver blade 113 according to the present disclosure is provided.

As shown in Figure 7, the above-mentioned movement of the driving piece 113, that is, the movement relative to the bearing ring 112, can be achieved by a central shaft 211 connected to the driving piece 113. The central shaft 211 can reciprocate along the radial direction of the annular bearing member 11. Move to drive the driving piece 113 to move in the radial direction.

It can also be observed that the above-mentioned movement of the driving piece 113, that is, the movement relative to the bearing ring 112, can also be realized by the angle adjustment assembly 212. The angle adjustment assembly 212 includes a clockwise and counterclockwise rotation provided on the central shaft 211. The rotating member 2121 and the transmission member 2122 fixedly provided on the driving piece 113 and engaged with the rotating member 2121, wherein the angle adjustment assembly 212 is configured to engage with the rotating member 2121 through clockwise and counterclockwise rotation of the rotating member 2121 The transmission member 2122 moves along the circumferential direction of the annular bearing member 11, thereby driving the driving piece 113 to move along the circumferential direction.

More specifically, the transmission member 2122 may include, for example, a transmission rod 3111 engaged with the rotating member 2121, a guide rail 3112 fixedly provided on the driving piece 113, and a pair of fixing screws 3113, wherein the transmission rod 3111 has a screw extending from both ends thereof. A pair of arm parts, and the pair of fixing screws 3113 fixedly connect the pair of arm parts to the guide rail 3112 respectively. Therefore, the clockwise and counterclockwise rotation of the rotating member 2121 causes the transmission rod 3111 engaged with the rotating member 2121 and the guide rail 3112 connected to the transmission rod 3111 to move in the circumferential direction, thereby driving the driving piece 113 in the circumferential direction. direction movement.

According to embodiments of the present disclosure, the driving piece 113 may be made of a high-strength and high-toughness alloy.

In this way, the possibility of the driving plate 113 being worn or deformed, for example, in a crushing collision with the wafer can be reduced.

It is conceivable that, as shown in FIG. 7 , the surface of the protruding portion 1131 of the driving piece 113 for engaging with the positioning groove may be plated with a wear-resistant layer 1132 .

In this way, the wear resistance of the driving piece 113, especially the protruding portion 1131, can be effectively enhanced.

It is also conceivable that the driving piece 113 may be provided with a buffer hole 1133 for stress relief. The buffer hole 1133 may be arranged, for example, at a position on the inside of the protruding portion 1131 of the driving piece 113 .

The above-mentioned improvements to the material and structure of the driving piece 113 make it possible to reduce the frequency of its replacement and maintenance, and thereby further increase the equipment productivity.

On the other hand, according to embodiments of the present disclosure, the outer shell 111 of the annular carrier 11 may be made of a low-expansion alloy.

Since the annular bearing member 11 needs to operate at high speed (for example, 4000 to 6000 rpm) and brake during the grinding process, a considerable part of the kinetic energy will be converted into heat energy during the grinding process. In this case, the outer shell 111 will expand due to heat, thus Deformation may occur, which may lead to the risk of deformation of the load-bearing ring 112 and the driving piece 113 , which may have a serious impact on the processing process and quality control. In the present disclosure, the shell 111 is made of low-expansion alloy, which has the characteristics of small expansion coefficient and low thermal conductivity, so it can effectively avoid the above problems. Moreover, the shell made of alloy has relatively high strength and is not easy to wear.

Next, a double-side grinding process or a double-side grinding method using a double-side grinding device according to an embodiment of the present disclosure will be described in detail. It should be noted that the double-sided grinding device referred to in this description is only exemplary, and therefore the double-sided grinding method is also exemplary.

After the previous process, the wafer is picked up by a robotic arm and moved into the grinding chamber. When the wafer is moved into the annular carrier, the static pressure plates on both sides start to operate, the right static pressure plate moves toward the wafer, and the air holes in the air injection area of the gas sensing unit begin to eject outwards, and the left static pressure plate The gas-sensitive sensing area at the corresponding position on the board receives the air jet and thereby determines the exact position of the positioning groove of the wafer. Based on this position information, the control unit controls the ring-shaped carrier to rotate slightly to drive the driving piece to the position corresponding to the positioning groove. The position of The wafer is loaded into the annular carrier by snapping. After that, the wafer is kept balanced by the gas injected from the air holes respectively provided on the two static pressure plates. Subsequently, the robotic arm moves out, and the grinding wheel passes through the through hole of the static pressure plate and is fed toward the wafer to be processed, and the opposite sides of the wafer to be processed are ground by the rotating grinding wheel.

After the grinding is completed, the annular carrier gradually stops rotating, and the driver plate completes the braking of the wafer. The grinding wheels on both sides stop rotating and exit backward through the through holes of the static pressure plate. The pores on the static pressure plate begin to vacuum and adsorb the wafer to the right static pressure plate. At this time, the grinding chamber door opens. The robotic arm moves in and takes out the processed wafers and sends them to the next process.

The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure. All are covered by the protection scope of this disclosure. Therefore, the protection scope of the present disclosure should be subject to the protection scope of the claims.

Claims (10)

1. A double-sided grinding device, including: An annular carrier, which includes a housing, a carrier ring provided on the inner peripheral side of the housing for radially supporting the outer peripheral side of the wafer to be processed, and a carrier ring provided on the carrier ring for snapping the The driver piece for the positioning groove of the wafer to be processed; Two static pressure plates, the two static pressure plates are symmetrically arranged on both sides of the annular bearing member; Two grinding wheels, the two grinding wheels are symmetrically arranged on both sides of the annular bearing member; A gas-sensitive sensing unit, which includes a gas-sensitive sensing area and a gas-jet area respectively arranged on the two static pressure plates in a corresponding manner, the gas-sensitive sensing area and the gas-jet area being positioned to enable passage of the gas The sensitive area senses the air jet from the air jet area to determine the position of the positioning groove of the wafer to be processed; and A control unit capable of controlling the rotation of the annular carrier based on the determined position of the positioning groove to drive the driving piece to a position corresponding to the positioning groove. 2. The double-sided grinding device according to claim 1, wherein the driving piece is movable relative to the bearing ring, and the control unit is capable of moving based on the determined position of the positioning groove. To control the movement of the driving piece relative to the bearing ring to adjust the position of the driving piece. 3. The double-sided grinding device according to claim 2, wherein the movement of the driving piece is movement along the radial direction and/or the circumferential direction of the annular bearing member. 4. The double-sided grinding device according to claim 2, wherein the movement of the driving piece is realized through a central shaft connected to the driving piece, and the central shaft can carry the load along the annular shape. The component moves back and forth in the radial direction to drive the driving piece to move along the radial direction. 5. The double-sided grinding device according to claim 4, characterized in that the movement of the driving piece is also realized by an angle adjustment assembly, and the angle adjustment assembly includes a device disposed on the central axis capable of performing A rotating member that rotates clockwise and counterclockwise and a transmission member fixedly provided on the driving piece and engaged with the rotating member, wherein the angle adjustment assembly is configured to rotate clockwise and counterclockwise through the rotating member To move the transmission member engaged with the rotating member along the circumferential direction of the annular bearing member, thereby driving the driving piece to move along the circumferential direction. 6. The double-sided grinding device according to any one of claims 1 to 5, characterized in that the driving piece is made of high-strength and high-toughness alloy. 7. The double-sided grinding device according to any one of claims 1 to 5, characterized in that the surface of the protruding portion of the driving piece for engaging with the positioning groove is plated with a wear-resistant layer . 8. The double-sided grinding device according to any one of claims 1 to 5, wherein the driving piece is provided with a buffer hole for stress relief. 9. The double-sided grinding device according to any one of claims 1 to 5, characterized in that the outer shell of the annular carrier is made of a low-expansion alloy. 10. A double-sided grinding method, the double-sided grinding method is performed using the double-sided grinding device according to any one of claims 1 to 9, the double-sided grinding method includes: Load the wafer to be processed into the annular carrier by engaging the driving piece with the positioning groove of the wafer to be processed; The wafer to be processed is kept balanced by gas injected from air holes respectively provided on the two static pressure plates; and The two grinding wheels grind the opposite sides of the wafer to be processed.