KR100758691B1 - System for aligning wafers and method thereof - Google Patents

Abstract

A system and a method for aligning a wafer are provided to count the wafers supplied into a batch, to exactly and rapidly align the wafer, and to read the characteristic of each wafer. A base(11) is installed on a lower portion of a batch(10). A wafer alignment apparatus(12) is installed on the base to align a wafer. A transfer apparatus(13) supplies the wafer to the wafer alignment apparatus or transfers the aligned wafer. A driving apparatus(14) moves the base and alignment apparatus front and back. A lift apparatus(19) lifts each wafer mounted on the transfer apparatus upward. A count apparatus(22) count the number of the wafer mounted on the transfer apparatus. The driving apparatus includes a fixed bracket(15), a driving load(16), and an actuator(17). The fixed bracket is fixed at a side end of the base and has a bare wire therein. The driving load is screw-coupled to the fixed bracket. The actuator rotates the driving load reversibly.

Description

System for aligning wafers and method

1 is a perspective view of an overall wafer alignment system in accordance with the present invention;

FIG. 2 is a schematic perspective view of an alignment apparatus applied to the wafer alignment system of FIG. 1. FIG.

3 is a front sectional view of the alignment device shown in FIG. 2.

4 is a schematic cross-sectional view for showing a first revolving roller provided in the alignment device shown in FIG.

5 is an enlarged cross sectional view of a portion of the first revolving roller;

6 is a sectional view of the alignment roller and the second idle roller.

7 is a flow chart showing a wafer alignment method by the wafer alignment system according to the present invention.

* Description of the symbols for the main parts of the drawings *

10: batch 12: wafer aligner

13: conveying device 14: driving device

19: lift device 20: count device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer alignment system, and more particularly, to a wafer alignment system capable of counting the number of wafers and aligning wafers more accurately and quickly, and also using a wafer alignment system using the wafer alignment system. It is about a method.

Generally, in the manufacturing process of a semiconductor device such as a wafer, the wafer as the substrate is cleaned with a cleaning liquid such as a predetermined chemical liquid or pure water, and the contamination such as particles, organic contaminants, metal impurities, etc. adhered to the surface of the wafer. A cleaning system for removing the ethylene is used. Among them, a wet cleaning system is widely used because it can effectively remove particles adhering to a substrate and can be cleaned by a batch treatment.

On the other hand, in order to perform such a cleaning process, an alignment system for aligning wafers carried or transferred into the cleaning process is indispensable. That is, in order to clean a wafer or perform another processing process, the process of aligning a wafer is performed. Such wafer alignment may be performed using notches formed on one side of the circumference of the wafer. For example, an alignment device in a wafer alignment system is achieved by rotating the wafer until the notch of the individual wafer engages with the alignment roller while rotating the plurality of wafers, and eventually rotating the wafer until the notch of all the wafers engages with the alignment roller. . That is, the wafers are aligned by aligning the notches all on the alignment rollers.

However, in the conventional wafer alignment system, it is not possible to accurately recognize or detect the alignment state or the misalignment state of the wafers when the wafers are transferred up and down by the loading mechanism before being aligned in the alignment device. There is a problem that can not be counted can be delayed or performed correctly in the subsequent or transfer process.

The present invention has been invented to solve the above problems, the object of the present invention is to align the wafer accurately, the wafer alignment system that can perform the subsequent process quickly and smoothly by counting the number of wafers and It is to provide a wafer alignment method using the alignment system.

Wafer alignment system according to an embodiment of the present invention is a batch; A base installed in the inner lower portion of the arrangement; An alignment device installed at the base to align the wafer; A conveying device for supplying a wafer to the wafer sorting device or conveying the aligned wafers; A drive device for reciprocating the base and the alignment device; A lift device for lifting upward each wafer loaded on the transfer device; And a counting device for counting the number of wafers loaded in the transfer device.

In addition, the wafer alignment method according to an embodiment of the present invention comprises the steps of checking whether the wafer is loaded in the conveying apparatus; Counting the number of wafers, when it is confirmed that the wafers are loaded in the transfer apparatus; When the number of sheets of the wafer is completed, transferring the conveying apparatus to the sorting apparatus, unloading the sorting apparatus, and then sorting the wafers; Storing the aligned wafers by the alignment device in a transfer device and moving the wafers to a predetermined position, and then reading the unique number of each wafer by an optical character reader (OCR) method; And transmitting the result of reading the unique number of each wafer and the history of the wafer to a controller for processing and storing and processing the wafer.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view showing an overall wafer alignment system according to the present invention, FIG. 2 is a schematic perspective view of an alignment device applied to the wafer alignment system of FIG. 1, and FIG. 3 is a front view of the alignment device shown in FIG. 4 is a schematic cross-sectional view for showing a first idle roller provided in the alignment device shown in FIG. 2, FIG. 5 is an enlarged cross-sectional view of a portion of the first idle roller, and FIG. 2 is a cross-sectional view of a second idler roller, and FIG. 7 is a flowchart showing a wafer alignment method by the wafer alignment system according to the present invention.

First, in Fig. 1, the wafer alignment system according to the present invention basically has a batch 10 formed in a predetermined shape. The batch 10 is formed in a rectangular or other suitable shape and in practice the wafer can be suitably processed.

The base 11 formed to a predetermined length in the left-right direction is installed in the inner lower part of the arrangement. In the base 11, a wafer aligning device 12 for actually aligning the wafer W is fixedly installed. The base 11 is preferably formed in a rail shape.

In addition, a wafer transfer device 13 for supplying wafers to the wafer aligning device 12 or transferring the aligned wafers to another place is formed above the wafer aligning device 12.

On the other hand, the base 11 is provided with a driving device 14 for transferring the base 11 and the wafer alignment device 12. The driving device 14 includes a fixing bracket 15 fixed to one end of the base 11 and having a spiral therein, and a driving rod 16 screwed to the fixing bracket 15. The actuator rod 17 is provided with an actuator 17 for moving the base 11 by rotating the drive rod 16. The actuator 17 is preferably formed of a reversible motor capable of forward rotation and reverse rotation.

In addition, one end of the base 11 or one side of the fixing bracket 15 is provided with a lift device 19 for lifting the respective wafers W loaded on the transfer device 13 upward. The lift device 19 is provided with an up / down cylinder 20 and a lift member 21 for reciprocating up and down with respect to the up / down cylinder 20 and actually lifting the wafer W. desirable.

On the other hand, according to the main feature of the present invention, it is preferable that the other end of the base 11 is provided with a counting device 22 that can count the alignment and the number of wafers. The counting device 22 includes a fixed member 23 fixedly installed at the other end of the base 11, a movable member 24 capable of reciprocating up and down with respect to the fixed member 23, and an upper end of the movable member 24. It consists of a guide (25) rotatably installed in the guide groove (25a) is formed in the longitudinal direction, the CCD sensor (26) that is movable in the guide groove (25a) of the guide (25). The CCD sensor 26 is preferably configured to count the number of wafers as well as the alignment state of the wafers W in the transfer device 13.

Meanwhile, as illustrated in FIGS. 2 to 6, the wafer alignment device 12 includes a bottom frame fixed to the side frames 31 and 32, the front frame 33, the back frame 34, and the base 11. It consists of 36. Each frame structure is formed of a hexahedron having an open top as a whole. Inside the frame structure, an intermediate frame 35 is installed between the side frames 31 and 32 in parallel with the side frames 31 and 32. Guide grooves 31a, 32a, and 35a are formed on the upper surfaces of the side frames 31 and 32 and the intermediate frame 35, respectively. Guide grooves 31a, 32a, 35a are grooves in which the wafer is aligned so that the circumferential surface of the wafer is accommodated therein.

In the frame structure, the driving roller 45, the alignment roller 46, the first idle roller 47, and the second idle roller 48 are rotatable with respect to each other and are rotatably provided with each other. The second idler roller 48 is disposed below and perpendicular to the alignment roller 46. Although not shown in the drawings, a drive motor is installed inside the frame structure, one end of the rotating shaft of the drive motor (not shown) protrudes outward of the front frame 33, and the driving pulley 41 at one end of the rotating shaft. ) Is fixed. In addition, one end of the rotation shaft of the drive roller 45 also protrudes to the outside of the front frame 33, the driven pulley 43 is fixed to one end of the rotation shaft of the drive roller 45. The belt 42 is installed between the driving pulley 41 and the driven pulley 43, and thus a driving force of a motor (not shown) may be transmitted through the belt 42 to rotate the driving roller 45.

The first revolving roller 47 is rotatably installed between the side frame 31 and the intermediate frame 35 at opposite positions of the drive roller 45. In the first revolving roller 47, a plurality of individual rollers each having grooves in contact with the circumferential surface of the wafer are rotatably installed on the same axis through the bearing. Therefore, the first idle roller 47 is provided with a plurality of individual rollers, the plurality of individual rollers can be rotated independently.

In addition, the first idle roller 47 is a number of individual rollers 55 are rotatably installed through the bearing 51 with respect to the fixed shaft (52). The individual rollers 55 are provided with grooves 55a formed through the circumferential surface. Preferably, the grooves 55a formed in the individual rollers 55 have a U-shape or a V-shape in the cross-sectional shape thereof. The circumferential surface of the wafer rotates while being inserted into the grooves 55a of the individual rollers 55, wherein the grooves 55a having a U-shape or a V-shape rotate the wafer while minimizing a contact area with the wafer. To support it. That is, while minimizing the contact of the individual rollers 55 to surfaces other than the circumferential surface of the wafer, it prevents the wafer from rotating out of the grooves 55a while tilting with respect to the axis of the first idle roller 47. .

The first idler roller 47 comprises a plurality of individual rollers 55 so that each wafer rotates in the groove 55a of the individual roller 55 of the first idler roller 47. It is intended to be able to rotate independently. As will be described later, each wafer stops rotation by inserting the notch formed in the wafer into the groove of the alignment roller 46. That is, when the wafer is rotated, the individual roller 55 is inserted into the circumference of the wafer is rotated, but when the rotation of the wafer is stopped due to the alignment of the wafer, the individual roller is formed with a groove (55a) is inserted into the circumference of the wafer 55 also stops rotating. At this time, the stopping of the rotation of one individual roller 55 does not affect the rotation of the other individual roller 55, as described above, in which the individual rollers 55 are independent through their respective bearings 51. Because it rotates.

On the other hand, the second revolving roller 48 is disposed below the alignment roller 46. The alignment roller 46 and the second revolving roller 48 are rotatably supported by the support 60. The support 60 may change the position of the alignment roller 46 and the second idler roller 48 by moving in the frame structure while supporting the alignment roller 46 and the second idler roller 48. . The alignment roller 46 and the second idler roller 48 are kept in contact with each other. The support 60 is installed on the end of the link 50, which may be proximate or spaced apart from the drive roller 45 by the action of the actuator 65. In addition, when the link member 50 changes the position of the support part 60 by the action of the actuator 65, the second idler roller 48 can move to a position where it can contact the driving roller 45. The second idler roller 48 in contact with the drive roller 45 can rotate the alignment roller 46.

The groove 46a is formed on the circumferential surface of the alignment roller 46. By forming the groove 46a in the alignment roller 46, when the notch formed in the circumference of the wafer is inserted in each groove 46a, the notch is engaged with the small diameter outer circumferential portion of the alignment roller 46, thus rotating the wafer. Will stop, and sorting will take place.

Hereinafter, the operation of the wafer alignment system according to the present invention and the wafer alignment method by the system will be described in detail.

First, the wafer W supplied from the outside by the cassette method is conveyed inside the batch 10 by the conveying apparatus 13. The conveying device 13 is disposed above the alignment device 12, and in this state, the counting device 20 moves the CCD sensor 22 to the upper part of the wafers W loaded on the conveying device 13. After that, the CCD sensor 22 checks the presence of the wafer (S110).

When it is confirmed that the wafer W is loaded in the conveying apparatus 12, the number of the wafers W loaded in the conveying apparatus 12 is counted by the lift apparatus 19 (S120). At this time, when the up / down cylinder 20 is operated by the lift device 19, the lift member 21 lifts the wafer W upwards, and the CCD sensor 22 of the counting device 20 does this. The number of wafers W is counted by sensing. At this time, the counting device 20 and the lift device 19 are able to count the number of sheets while moving left and right by the driving device 14. That is, when the actuator 17 is operated to rotate the driving rod 16 in the forward or reverse direction, when the fixing bracket 15 and the base 11 screwed to the driving rod 16 are moved left and right, the counting device ( 20) In addition, the CCD sensor 22 can count the number and state of a given wafer W while moving from side to side.

When the counting of the number of wafers W is completed by the counting device 20 as described above, the wafer W is transferred to the sorting device 12 while the conveying device 12 is transferred onto the sorting device 12. After unloading, the wafer W is aligned (S130).

In more detail with regard to the alignment of the wafers, each of the wafers W loaded on the alignment device 12 is supported by its outer circumference in contact with the surfaces of the drive roller 45 and the first revolving roller 47. At this time, the outer circumference of the wafer W is inserted into the groove 55a of the individual roller 55 of the first revolving roller 47. Thereafter, when the link 50 brings the support 60 close to the driving roller 45 by the action of the actuator 65, the second idle roller 48 comes into contact with the driving roller 45. In addition, the alignment roller 46 also comes into contact with the wafer W so that the circumference of the wafer W is inserted into the groove 46a formed in the alignment roller 46. Next, when the drive motor 45 is rotated by the rotation of the motor (not shown), the wafer W is rotated while being supported by the drive motor 45 and the alignment roller 46. The second idler roller 65 supports the alignment roller 46 to prevent the alignment roller 46 from knocking out due to the weight of the wafer. When the wafer W rotates, the notch 10 formed in the wafer W is engaged with the small diameter outer circumferential portion formed in the groove 46a of the alignment roller 46. When the notches 10 of all the wafers are engaged with the small diameter outer peripheral portion of the alignment roller 46, the alignment is made. Thereafter, the support 60 is withdrawn by the action of the actuator 65 and the link 50, so that the second idle roller 48 is spaced apart from the drive roller 45. At this time, the wafer is supported in the groove 55a of the surface of the drive roller 45 and the individual roller 55 of the first revolving roller 47 in the aligned state. The drive roller 45 is then rotated at an angle, to rearrange the aligned wafers in the desired direction. As the drive roller 45 rotates, the wafers aligned with respect to each other can be aligned at a predetermined angle by simultaneously rotating the same angle. At this time, the wafer inserted into the groove 55a of the individual roller 55 of the first revolving roller 47 has a U-shaped or V-shaped groove 55a, so that the side surface of the wafer has an inner surface of the groove 55a. Friction is minimized because there is no contact, and can be automatically calibrated because the circumferential surface of the wafer is held at the deepest portion of the U or V shape.

As described above, when the alignment of the wafer is completed, the transfer device 13 moves to the upper portion of the alignment device 12 again to store the wafer W, and then moves to a predetermined position. The unique number of each wafer W detected by the CCD sensor 22 of the apparatus 20 is read by the optical character reader (OCR) method (S140).

When the reading of the unique number of each wafer W is completed, the reading result and the history of the corresponding wafer are transmitted to the controller which actually performs the processing and stored and processed (S150).

Thereafter, of course, the conveying apparatus 13 is to transfer the wafer W to a predetermined process or another batch for post-processing, or to load and move the wafer W in a cassette.

Therefore, accurate alignment of wafers and the number and reading of each wafer can be performed simultaneously.

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, it is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible. will be. Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

According to the wafer alignment system according to the present invention, the number of wafers supplied into the batch can be counted, the wafers can be aligned accurately and quickly, as well as the characteristics of each wafer can be read, thereby providing efficient wafers. There is an effect that the processing operation can be performed.

Claims (11)

arrangement; A base installed in the inner lower portion of the arrangement; An alignment device installed at the base to align the wafer; A conveying device for supplying a wafer to the wafer sorting device or conveying the aligned wafers; A drive device for reciprocating the base and the alignment device; A lift device for lifting upward each wafer loaded on the transfer device; And And a counting device for counting the number of wafers loaded in the conveying device. According to claim 2, wherein the drive device is fixed to one end of the base and has a fixing bracket having a spiral therein, a drive rod screwed to the fixing bracket, and an actuator for reversibly rotating the drive rod Wafer sorting system. The wafer alignment system of claim 1, wherein the lift device comprises an up / down cylinder and a lift member configured to reciprocate up and down with respect to the up / down cylinder and lift the wafer. The wafer counting apparatus of claim 1, wherein the wafer counting device includes a fixed member fixedly installed at the other end of the base, a movable member reciprocating up and down with respect to the fixed member, and rotatably installed at an upper end of the movable member. A wafer alignment system comprising a guide formed in the longitudinal direction and a CCD sensor movably installed in the guide groove of the guide. The method of claim 1, wherein the alignment device A frame structure formed of a hexahedron shape having an upper portion open; A driving roller rotatably maintained at one side of the frame structure; A first revolving roller disposed on the other side of the frame structure in parallel with the driving roller and rotatably maintained, the first revolving roller having a plurality of individual rollers having grooves into which outer circumferences of the wafer can be inserted; A second idler roller movable between a proximal position that can be rotated in contact with the drive roller and a spaced apart position away from it; And And an alignment roller disposed rotatably in contact with the second idle roller, the alignment roller having a groove formed with a small diameter portion to which the notch of the wafer is engaged. 6. The wafer of claim 5, further comprising: a support for movably holding the second idler roller and the alignment roller in the frame structure; and an actuator for moving the support between the proximal position and the spaced apart position. Sorting system. The wafer alignment system of claim 5, wherein the driving roller receives the rotational force of a driving motor provided in the frame structure through a belt and is driven to rotate. 6. The wafer as claimed in claim 5, wherein the wafer inserted into and supported by the outer surface of the drive roller and the groove of the alignment roller is rotated by rotational driving of the drive roller, and the notch of the wafer is formed on the small diameter outer circumferential portion of the alignment roller. A wafer alignment system in which rotation of the wafer is stopped by engaging. 6. The method of claim 5, wherein after the alignment of the wafer is finished, the alignment roller and the second idler roller are spaced apart from the drive roller, after which the wafer is placed on the outer surface of the drive roller and the individual roller of the first idler roller. A wafer alignment system inserted into and supported in the formed grooves. 6. The wafer alignment system of claim 5, wherein the grooves formed in the individual rollers of the first revolving roller are U-shaped or V-shaped in cross section. Confirming whether the wafer is loaded in the conveying apparatus; Counting the number of wafers, when it is confirmed that the wafers are loaded in the transfer apparatus; When the number of sheets of the wafer is completed, transferring the conveying apparatus to the sorting apparatus, unloading the sorting apparatus, and then sorting the wafers; Storing the aligned wafers by the alignment device in a transfer device and moving the wafers to a predetermined position, and then reading the unique number of each wafer by an optical character reader (OCR) method; And And transferring the result of reading the unique number of each wafer and a history of the wafer to a controller for processing and storing and processing the wafer.

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