JP2001198781A - Method and device for polishing board edge section - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for polishing board edges section with a polishing band. SOLUTION: This device has board holding member for rotatably holding one side face of the board and a support member detachable relatively from the board holding member, and the support member has a groove formed for receiving the edge section of the board, and the groove is covered by the polishing band let out from the groove in order.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for polishing an edge portion of a substrate, and more particularly, to an edge portion which is an outer peripheral portion of a disk-shaped substrate such as a semiconductor wafer, a glass plate, a quartz plate and a ceramic substrate. The present invention relates to a polishing method and an apparatus for mirror polishing.

[0002]

2. Description of the Related Art For example, a wafer used as a substrate of a semiconductor device is obtained by slicing a single crystal ingot such as silicon at right angles to the axial direction thereof.
The sliced product is manufactured by going through processes such as chamfering, lapping, etching, annealing, and polishing. The main purpose of the chamfering performed in the wafer manufacturing process as described above is to prevent chipping at the edge portion of the wafer, and in this chamfering, a method of scraping the wafer edge portion with a hard rigid grindstone is usually adopted. ing.

However, in recent years, as the density of semiconductor devices has increased, measures against dust generation in the manufacturing process have become more stringent, and it has become an important requirement that no dust is generated even on the wafer as a material. As a result, the necessity of polishing the wafer edge part as much as the mirror surface part of the wafer has been increased. As a polishing apparatus for polishing an edge portion, which is a chamfered portion of a wafer, those disclosed in Japanese Patent Nos. 2815797 and 2889108 are known.

In the apparatus disclosed in Japanese Patent No. 2815797, an arc-shaped polishing groove having a curvature substantially coinciding with an outer peripheral portion of an edge portion of a wafer is formed in a polishing buff, and an outer peripheral portion of the wafer is formed in the arc-shaped polishing groove. That is, the polishing is performed by pressing the wafer edge portion. Further, the apparatus disclosed in Japanese Patent No. 2889108 is configured so that the polishing tape wound and housed inside the rotating drum is fed out to the peripheral surface of the rotating drum, the rotating drum is wound, and then wound again inside. The edge of the wafer is polished by a portion of the polishing tape located on the peripheral surface of the rotating drum, and at the time of this polishing, the rotating drum is inclined at a predetermined swing angle in the front-rear direction by the swing means. It is what was constituted.

[0005] However, in the apparatus disclosed in Japanese Patent No. 2815797, an arc-shaped polishing groove substantially coinciding with the edge of the wafer is formed in the polishing buff itself, and the arc-shaped polishing groove is pressed against the edge of the wafer. Therefore, it is necessary to always press the arc-shaped polishing groove against the edge of the wafer from a fixed direction. If the direction is shifted, the polishing of the edge of the wafer is unstable. Further, when arc-shaped polishing grooves are formed in the polishing buff, there are various chamfered shapes at the edge portion of the wafer to be polished, so that it is necessary to prepare a plurality of grooves, which is complicated. Further, the shape of the arc-shaped polishing groove gradually wears due to polishing, and when the shape is excessively worn, not only the edge portion of the wafer but also a flat portion may be polished. There are various problems.

On the other hand, in the apparatus disclosed in Japanese Patent No. 2889108, it is necessary to incline the rotary drum in the front-back direction at the time of polishing, and the inclining mechanism for inclining the drum is complicated. In addition, there is a problem that it becomes expensive.

Further, there is an apparatus in which grooves of various sizes are provided in a polishing band located outside a support portion, and polishing is performed by pressing an edge portion of a wafer into a matching groove. However, there is a fear that the shape of the groove is different due to polishing, the groove does not match the edge portion of the wafer, and good polishing cannot be performed.

Japanese Patent Application Laid-Open No. 7-193030 discloses an apparatus using a polishing band having no groove formed therein. In this apparatus, abrasive grains are embedded in the polishing band. Since the polishing band in which the abrasive grains are embedded is moved with respect to the wafer edge, the wafer edge is ground rather than polished. Therefore, it is necessary to always move the polishing band during grinding, and when the movement is stopped, grinding marks of the last contacting abrasive grains are formed, but such a structure is necessary to remove the polysilicon film. There is. On the other hand, in the configuration shown in the present application as described later, the abrasive band is not embedded in the polishing band itself for the configuration for polishing the substrate edge portion, and the polishing band is stopped during polishing. It has become. Therefore, the object of the present invention is completely different from the object disclosed in Japanese Patent Application Laid-Open No. 7-193030.

As described above, the conventional apparatus has various problems, and furthermore, the polishing apparatus needs to finish the entire surface of the wafer in a mirror state, so that the wafer itself is supported. It is necessary to reduce the number of portions of the wafer support mechanism that come into contact with the wafer, and it is necessary to minimize the number of contact portions when supporting the wafer.

[0010] An object of the present invention is to polish a variety of substrate edges with a single type of polishing band having no grooves without preparing a plurality of polishing bands having grooves formed therein. An object of the present invention is to provide a method and an apparatus for polishing an edge portion of a substrate which does not require a tilting mechanism because the substrate does not need to be tilted and which can be reduced in size and inexpensive. Another object of the present invention is to perform various types of polishing with a single type of polishing band having no grooves without preparing a plurality of polishing bands having grooves formed therein, and furthermore, tilt the substrate during polishing. Since there is no need, no tilting mechanism is required, the whole can be made small and inexpensive, and the pressing force applied when polishing the substrate edge can be adjusted to obtain a desired polishing state. An object of the present invention is to provide a method and an apparatus for polishing a substrate edge portion which can be performed.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an edge portion of a substrate rotatably held by a substrate holding member, a groove for receiving the edge portion and a cover for covering the groove. And the polishing band of the support member having a polishing band that can be sequentially fed is pressed against the groove, and the substrate is rotated while the feeding of the polishing band is stopped to polish the edge portion of the substrate. The above-mentioned measures were adopted. Further, the present invention has a substrate holding member rotatably holding one surface of the substrate, and a supporting member which can be relatively moved toward and away from the substrate holding member, and the supporting member has an edge portion of the substrate. A groove for receiving the groove, and a configuration in which a polishing band covering the groove is provided, and the present invention further includes a substrate holding member that rotatably holds one surface of the substrate,
A supporting member that can be relatively moved toward and away from the substrate holding member, the supporting member includes a base, and a pair of abutting portions that are vertically movably provided on one surface of the base. The pair of contact portions can be separated from and separated from each other, and cooperate between the two contact portions to form a groove for receiving an edge portion of the substrate,
It has a configuration in which a polishing band covering the groove is provided. The polishing band is positioned on one side of the groove in the wound state and the end is sequentially fed out, and the end after covering the groove is positioned on the other side of the groove and wound sequentially. Further, the feeding and winding of the polishing band are stopped at the time of polishing pressed against the groove by the edge of the substrate.

[0012]

According to the present invention, the above means are adopted.
Since the edge portion of the substrate is positioned and rotated while pressing the polishing band against the groove provided on the support member, the groove according to the shape of the edge portion of the substrate is not formed in the polishing band, and the entrance of the groove is sequentially formed. By positioning a part of the polishing band at the portion, the edge portion of the substrate can be reliably polished. In addition, the polishing band is wound and sequentially unwound and can be wound up, so that the movement of the polishing band is stopped during polishing, and is sent out and wound up during non-polishing, so that a portion of the new polishing band is sequentially formed on the substrate. It can be used for polishing by contacting the edge portion.

[0013]

Embodiments of the present invention shown in the drawings will be described below. FIG. 1 is a schematic view of a substrate edge polishing apparatus according to the present invention, FIG. 2 is a schematic view of a support member, and FIG. 3 shows a state in which the polishing apparatus moves to polish an edge of a substrate. A schematic diagram is shown.

The substrate edge polishing apparatus 1 comprises, for example, a wafer holding member 3 which holds a semiconductor wafer (hereinafter, referred to as a wafer) 2 in a horizontal state by means of, for example, vacuum suction or the like, and a rotatable holding member. And a support member 4 provided to be movable in the horizontal direction with respect to the rotation center axis 3 so as to be able to approach and separate.

The wafer holding member 3 is located substantially at the center of the polishing apparatus, and holds the wafer 2 transferred from a transfer member (not shown) upward by means such as suction.
And a rotation drive unit 6 configured to rotate the holding unit 5 in a horizontal direction by a drive source (not shown).

The support member 4 is sized to receive an edge of the wafer 2 held by the wafer holding member 3 at a substantially central portion in the vertical direction, and has a groove 7 extending in a horizontal direction. The supporting portion 8 is provided.
On the upper and lower portions of the support portion 8, there are a pair of support plates 9, 9 standing up against each other on both sides of the support portion 8, and a shaft 10 is provided between the support plates 9, 9. Guide part 1
1 are provided respectively. Although not shown, guide rollers 13 of the wound polishing bands 12 are provided on the guide portions 11 of the support portion 8, respectively.

A plurality of the support members 4 configured as described above are disposed around the wafer holding member 3, and each of the support members 4 approaches the rotation axis of the wafer holding member 3.・ It is arranged to be detachable.

Next, the operation of the above will be described. In the polishing apparatus configured as described above, first, the wafer 2 is transferred by a transfer member (not shown) and transferred to the wafer holding member 3. That is, the wafer holding member 3 holds the transported wafer 2 on the upper surface of the holding unit 5 by means such as suction, and then the holding unit 5 is rotated by the driving source via the rotation driving unit 6. It is rotated about the axis of the rotation drive unit 6.

On the other hand, the support member 4 is moved toward the rotation axis of the wafer holding member 3 from a state of being separated from the wafer holding member 3 by a horizontal movement source (not shown). This allows the edge portion 2 of the wafer 2
a comes to face the groove 7 of the support portion 8 of the support member 4. A plurality of support members 4 are provided around the wafer holding member 3.
When the wafers 2 are provided, it is preferable that the respective support members 4 are simultaneously moved so as to approach and separate from the wafer holding member 3.
Can be contacted at the same time.

Further, guide portions 11 and 11 are provided on the upper and lower portions of the support member 4, and one guide portion 11 has
The end portion of the wound polishing band 12 is guided by the drawn-out guide roller 13 and the shaft 10 and is positioned on the support portion 8. Thereafter, the end portion is wound via the shaft 10 of the other guide portion 11 and the guide roller 13. Have been. Therefore, the edge portion 2a of the wafer 2 facing the groove 7 provided in the support portion 8
Is in a state in which a polishing band 12 is interposed between the groove 7 and the groove 7.

When the support member 4 approaches the wafer holding member 3, the holding portion 5 of the wafer holding member 3 is moved.
The edge 2a of the wafer 2 held in the
The contact portion 2 is pressed to be located in the groove 7. When the rotation driving unit 6 of the wafer holding member 3 rotates in this state, the edge portion 2a of the wafer 2 is polished by being rubbed by the pressing portion of the polishing band 12.

In the edge portion 2a of the wafer 2, predetermined portions on the upper and lower surfaces and the end surface are pressed according to the shape of the groove 7, so that the pressed portion is polished. Therefore, if the groove 7 corresponding to the shape of the edge portion 2a to be polished is formed in the support portion 8, the edge portion 2a of any wafer 2 can be polished.

When the portion of the polishing band 12 subjected to polishing is worn out by polishing, the polishing band 12 is wound around one side, a new portion is opposed to the groove 7, and the polishing band is again subjected to polishing. is there. Therefore, the edge portion 2a of the wafer 2 can always be polished with the optimum polishing band 12, so that good polishing of the edge portion 2a can be ensured. In this case, it is possible to employ various things, such as winding the polishing band every predetermined time or winding the polishing band every predetermined rotation of the wafer holding member 3.

FIGS. 4 and 5 show another embodiment of the present invention. FIG. 4 is a schematic diagram showing a state before the edge of the wafer is polished, and FIG. It is the schematic which shows the state which is being grind | polished. In a polishing apparatus 21 for a substrate edge portion shown in this embodiment, a wafer holding member 23 has a holding portion 25 and a rotation driving portion 26 as in the above embodiment.

On the other hand, the support member 24 is formed integrally with an inwardly protruding portion 28 on an upper portion of a base 27 which stands upright. A guide portion 40 provided on the inner side surface of the base portion 27 has a pair of fixed portions 3 at predetermined intervals.
1, 31 are provided so as to be able to move up and down while maintaining the interval. Further, a supporting portion 41 is provided between the pair of fixing portions 31, 31 so as to be vertically movable with respect to the fixing portion 31, and an urging member 32 such as a spring is provided between the pair of fixing portions 31, 31. Are arranged. The lower fixing portion 31 and the supporting portion 41 are in contact with the contact portions 30a, 30a.
b is provided. Further, the pair of contact portions 30
Tapered portions 29a and 29b facing each other are formed on the portions a and 30b. The contact portions 30a and 30b may be close to or in contact with each other in a normal state.

Therefore, the upper and lower contact portions 30
a and 30b are held in contact with or close to each other by an urging member 32 such as the spring, and both contact portions 3
A V-shaped groove 43 is formed between the tapered portions 29a and 29b of the wafer 2a.
Is to match.

Further, the base 27 above the fixing portion 31
Is integrally provided with a guide portion 34 provided with a roller 33 at the tip thereof. Further, a cylinder 35 is provided on the protruding portion 28 located above the guide portion 34, and an operating portion 35a of the cylinder 35 Is provided with a pressing portion 36 which can be pressed on the upper surface of the guide portion 34.

Below the pair of contact portions 30a and 30b, there is provided a pair of guide rollers 38 for guiding the polishing band 37 contacting the end surfaces 29c of the both contact portions 30a and 30b. Is provided with a holding portion (not shown) for holding the polishing band 37 wound so as to be able to be fed and wound up.

The operation of the apparatus for polishing a wafer edge portion according to this embodiment configured as described above will be described. First, the polishing band 37 is positioned between the two holding portions. The polishing band 37 wound around one of the holding portions is positioned, and the end is extended to be positioned between the pair of guide rollers 38. Note that the pair of guide rollers 38 is configured to sandwich the polishing band 37.

After that, the polishing band 37 is connected to both contact portions 30a, 3a.
0b reaches the roller 33 after coming into contact with the end surface 29c,
Further, a hole 27a provided in the base 27 is inserted through the upper surface of the guide portion 34 so as to be wound around the other holding portion. At the same time, the operating portion 35 of the cylinder 35
a protrudes and presses the pressing portion 36 against the guide portion 34,
Thus, the polishing band 37 is sandwiched between the pair of guide rollers 38 and between the pressing portion 36 and the guide portion 34 so that the polishing band 37 does not move. Note that the polishing band 37 is not limited to the case where the portion subjected to polishing is sequentially wound and passed through the roller 33, and conversely,
May be configured to be wound and then passed through the guide roller 38 after the portion sequentially passing through is subjected to polishing,
In any case, at the time of polishing, the movement of the polishing band 37 is temporarily stopped.

On the other hand, the holding portion 2 of the wafer holding member 23
The wafer 2 is held, for example, by suction at a transfer member 5 (not shown). When the above preparation is completed, the support member 24 is moved toward the wafer holding member 23 so that the edge 2 a of the wafer 2 is brought into contact with the polishing band 37. When the support member 24 is further moved, the edge portion 2a of the wafer 2 is brought into contact with the two contact portions 30a,
Press 0b.

At this time, the edge 2a of the wafer 2 is pressed by the action of the urging force of the urging member 32 so as to be gripped by the polishing band 37, and the taper 29a of the abutting portions 30a, 30b. , 29b press the polishing band 37 with substantially the same force. Further, both contact portions 30a, 30b
Is movable up and down with respect to the substrate 27, so that even if the groove 43 formed between the contact portions 30a and 30b is vertically displaced with respect to the edge 2a of the wafer 2, The groove 43 formed by the contact portions 30a and 30b follows.

Therefore, the upper and lower surfaces of the edge 2a of the wafer 2 press the polishing band 37 with substantially the same force, while the polishing band 37 is pressed against the end surface of the edge 2a of the wafer 2. Edge portion 2a is reliably pressed by the polishing band 37 and polished.

Then, as shown in FIG. 5, by supplying the slurry to the edge portion of the wafer from the nozzle 44 or the like, the polishing state can be improved. Further, similarly to the above-described embodiment, during the polishing, the feeding of the polishing band is stopped, and when the polishing belt is worn to some extent, the feeding is performed so that a new portion is exposed. In this case, conventionally known various means can be adopted for these operations. With this configuration, the polishing band can be used efficiently and the cost can be reduced.

In FIG. 6, a biasing member 32 such as a spring is applied so that the contact portions 30a and 30b come close to each other, and the contact portions 30a and 30b grip the wafer edge portion via the polishing band 37. Another embodiment is shown, and the same members as those in the above embodiment are denoted by the same reference numerals and description thereof will be omitted.

In this embodiment, a pair of fixed parts 31, 31 which can be moved up and down respectively are arranged on a guide part 40 provided on the inner side of the base part 27, and the pair of fixed parts 31, 31 is provided.
Are provided with contact portions 30a and 30b, respectively. The abutting portions 30a and 30b are formed with opposing tapered portions 29a and 29b, respectively, as in the above-described embodiment. An urging member 32 such as a spring is disposed between the contact portions 30a and 30b, and the contact members 30a and 30b are urged to approach each other. The contact portions 30a and 30b may be close to each other or may be in contact with each other in a normal state.

With this configuration, both contact portions 30
a, 30b can be moved up and down along the guide portion 40 in a state like a clothespin, so that both contact portions 30
The V-shaped groove 43 formed by the tapered portions 29a and 29b of the wafers 2a and 2b reliably follows the edge 2a of the wafer 2 through the polishing band 37 even if it is displaced from the edge 2a of the wafer 2. 2a can be grasped.

In any case, if the guide portion 34 is configured to have elasticity, the wound polishing band 37 is fed out and the edge portion of the wafer 2 is stopped in a state where the winding is stopped. 2a, the guide portion 3
Since the elastic force of 4 acts, the polishing band 37 can be brought into contact with the edge portion 2a of the wafer 2 with a larger pressing force to perform polishing.

With the structure shown in each of the above embodiments, the groove itself conforms to the shape of the wafer edge only by pressing the polishing band at the edge of the wafer. Part tilted downward, horizontal,
In addition, the polishing band can be reliably pressed against the edge portion of the wafer and polished without being inclined upward. Therefore, even when the edge of the wafer is round or trapezoidal, the groove is surely pressed against the edge of the wafer by forming the groove so that it conforms to the shape of the groove itself. can do.

In each of the above embodiments, the support member of the wafer holding member for supporting the wafer and the support member for supporting the polishing band is configured to be brought into contact with and separated from the wafer holding member. The reverse may be the case, and with respect to the moving mechanism for moving the moving member in and out, a wire and a balance weight are used on the conventionally known moving member side, and the moving member is moved by the balance weight.
Various mechanisms such as a mechanism for returning to the original state by the cylinder can be employed. Further, a plurality of support members are provided, and each of the support members is polished near the edge of the wafer during polishing, so that the polishing time can be greatly reduced.

[0041]

According to the present invention having the above-described structure, in the method according to the present invention, a polishing strip whose edge portion of the substrate can be sequentially fed out is pressed against the groove. Is rotated, so that when the polishing band is worn, a new portion of the polishing band can be exposed, so that the polishing efficiency is high. Further, in the apparatus according to the present invention, it is not necessary to form the groove in the polishing band as described above, and the edge portion of the substrate presses the polishing band into the groove formed in the support member to form the edge portion of the substrate. Since the polishing band can be polished, the manufacturing cost of the polishing band can be reduced, and when abrasion occurs to some extent, a new portion of the polishing band can be sequentially exposed, so that the entire polishing band can be used efficiently. , Manufacturing costs and running costs can be reduced. Further, in the device according to the present invention, a groove is formed between the pair of abutting portions, and the polishing band is covered at the entrance of the groove, so that no groove is formed in the polishing band. As a result, the manufacturing cost of the polishing band can be reduced, and when it has been worn to some extent, a new portion can be sequentially exposed, so that the entire polishing band can be used efficiently. Then, by pressing the edge portion of the substrate against the polishing band, the other contact portion approaches and separates from one contact portion against the urging force of the urging member, so that the groove is enlarged, or Can be smaller,
It can cope with the edges of all substrates, and at this time, since both protruding parts themselves can move up and down, even if the edges of the substrate are displaced vertically with respect to the grooves, Can be followed. Even when a groove is formed in the support member or when a groove is formed between both abutting portions, the groove itself can be made to conform to the shape of the edge of the substrate, so that the edge of the substrate is directed downward. The polishing band can be reliably pressed against the edge of the substrate without being inclined to the inclined state, the horizontal state, and the upward inclined state, and the edge of the substrate can be polished. Therefore, even when the edge portion of the substrate is round or trapezoidal, by configuring the shape of the groove itself to match it, the polishing band is reliably pressed against the edge portion of the substrate and polished. can do. Further, since the substrate holding member supports only one surface of the substrate, it has an effect that contact stains and the like can be reduced with respect to the substrate.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a polishing apparatus for a wafer edge portion according to an embodiment of the present invention.

FIG. 2 is a schematic view showing a support member used in the present invention.

FIG. 3 is a schematic view showing a state in which a polishing apparatus moves to polish an edge portion of a wafer.

FIG. 4 is a schematic view showing another embodiment of the present invention and showing a state before polishing an edge portion of a wafer.

FIG. 5 is a schematic view showing a state in which the edge portion of the wafer shown in FIG. 4 is being polished.

FIG. 6 is a schematic view showing another embodiment of the contact portion shown in FIG.

[Explanation of symbols]

 1, 21 Polishing device 2 Wafer 2a Edge portion 3, 23 Wafer holding member 4, 24 Support member 5, 25 Holding unit 6, 26 Rotation driving unit 7, 43 ... Groove 8... Supporting part 9. 29a, 29b Tapered section 29c End face 30a, 30b Contact section 31 Fixed section 32 Biasing member 33 Roller 35 Cylinder 35a Operating section 36 Pressing section 40 … Guide 41… Support 44… Nozzle

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masahiro Ichikawa 2647 Hayakawa Hayakawa, Ayase City, Kanagawa Prefecture Inside (72) Inventor Toshikuni Shimizu 2647 Hayakawa Hayakawa, Ayase City, Kanagawa Prefecture Inside F Speed Ipec Corporation Terms (reference) 3C049 AA05 AA14 AB09 CA01 CA02 CA05 CB03 CB05 3C058 AA05 AA14 AB09 CA05 CB03 CB05 DA18

Claims (5)

[Claims] 1. A support member having an edge portion of a substrate rotatably held by a substrate holding member, a groove for receiving the edge portion, and a polishing band covering the groove and capable of being sequentially fed out. Pressing the polishing strip of the above into the groove,
A method for polishing an edge portion of a substrate, wherein the substrate is rotated while the feeding of the polishing band is stopped, and the edge portion of the substrate is polished. 2. A substrate holding member for rotatably holding one side of a substrate, and a supporting member which can be relatively moved toward and away from the substrate holding member, wherein the supporting member has an edge portion of the substrate. A polishing apparatus for an edge portion of a substrate, wherein a groove for receiving the groove is formed and a polishing band covering the groove is provided. 3. A substrate holding member for rotatably holding one side of a substrate, and a supporting member which can be relatively moved toward and away from the substrate holding member, wherein the supporting member includes a base and the base. Has a pair of abutting portions projecting from one side thereof so as to be vertically movable, the pair of abutting portions can be separated from and separated from each other, and the edge portions of the substrate cooperate between the two abutting portions. A polishing device for a substrate edge portion, wherein a groove for receiving the groove is formed, and a polishing band covering the groove is provided. 4. The polishing band is positioned on one side of the groove in a wound state and the end is sequentially fed out, and the end after covering the groove is positioned on the other side of the groove and sequentially. 4. The apparatus for polishing a substrate edge portion according to claim 2, wherein the substrate is wound up. 5. The apparatus for polishing a substrate edge portion according to claim 4, wherein the feeding and winding of the polishing band are stopped at the time of polishing pressed against the groove by the edge portion of the substrate.