KR20070040997A - Apparatus of sensing for wafer alignment - Google Patents

Abstract

The present invention relates to a wafer alignment detection device. The present invention comprises a pair of alignment rollers that rotate while being in vertical contact with the bottom of the plurality of wafers, are arranged in parallel at regular intervals to match the flat zone of the wafer; A guide roller for guiding the wafer; A light emitting sensor for generating an optical signal to detect a flat zone of the wafer; And a light receiving sensor configured to receive an optical signal generated by the light emitting sensor, wherein the light receiving sensor is provided in a light receiving panel that is height-adjustable, and an edge of the light receiving panel is supported by a support frame. It provides a wafer alignment detection device, characterized in that. According to the wafer alignment detection device of the present invention, by holding and fixing the light receiving unit panel with the support frame and the support plate, vibration occurs when the cassette is placed on the wafer alignment table, or vibration is generated by rotation of the guide roller or the alignment roller. Even if the light-receiving panel is not twisted or changed in position, the flat zone of the wafer can be properly detected, thereby preventing the occurrence of an error, preventing the wafer from being broken, and preventing work loss due to malfunction of the device.

Wafer alignment detector, light receiving sensor, light emitting sensor, light receiving panel, support frame

Description

Wafer alignment detector {APPARATUS OF SENSING FOR WAFER ALIGNMENT}

1 is a schematic configuration diagram of a conventional wafer alignment detection device.

Figure 2 is a schematic perspective view of the wafer alignment detection device according to an embodiment of the present invention.

3 is a view showing a fixed state of the light receiving panel according to the present invention.

Figure 4 is a cross-sectional view showing a coupling state of the horizontal bar and the vertical bar of the support frame.

FIG. 5 is a sectional view taken along the line V of FIG. 2 when the wafer is in alignment;

6 is a cross-sectional view taken along the line VI of FIG. 2 when the wafer is in an unaligned state.

Figure 7 is a schematic perspective view of the wafer alignment detection device for explaining the method for confirming the wafer flat zone according to the present invention.

8 is a cross-sectional view taken along the line VII-VII of FIG. 7.

<Explanation of symbols for the main parts of the drawings>

10; Wafer alignment stage 13; cassette

15; Alignment roller 17; Guide Roller

20; Light emitting panel 22,24; Luminescent Sensor

30; Light-receiving panel 40; Support frame

50; Support Plate

The present invention relates to a wafer alignment detection device, and more particularly, to a wafer alignment detection device in which the height of the light receiving sensor does not change easily in spite of the surrounding vibration.

The manufacturing process of the semiconductor device requires a number of facilities such as diffusion equipment for diffusing impurities on the wafer, equipment for applying photoresist on the wafer, and equipment for exposing and developing the photoresist through a mask having a predetermined pattern. Do.

The wafer to be processed by the above-described facilities is loaded in a cassette and moved to each facility of a predetermined step to proceed with the process.

A wafer aligning device of KOKUSAI diffusion equipment among such semiconductor manufacturing facilities will be described with reference to FIG. 1.

1 is a schematic configuration diagram of a conventional wafer alignment detection device.

As shown in FIG. 1, the wafer alignment detection device includes a wafer alignment table 10 on which a cassette 13 is loaded, light emitting sensors 22 and 24, a light receiving sensor, and the like.

A guide roller (not shown) and an alignment roller (not shown) are provided on the wafer alignment table 10, and a cassette 13 on which a plurality of wafers W are placed is placed on the guide roller and the alignment roller.

 The light emitting sensors 22 and 24 and the light receiving sensors for detecting the flat zone of the wafer W with the cassette 13 interposed therebetween are installed at the corresponding heights, and the light emitting sensors 22 and 24 are provided with light emitting units. It is attached to the panel 20, and the light receiving sensor is attached to the light receiving part panel 30.

The light emitting panel 20 and the light receiving panel 30 are vertically installed with respect to the wafer alignment table 10, and the light emitting panel 20 is fixed to the wafer alignment table 10, while the light receiving panel 30 is installed. ) Is installed on the sidewall of the wafer alignment table 10 to enable height adjustment.

The light receiving part panel 30 has two length adjusting screw grooves formed in the longitudinal direction so as to be coupled to the sidewalls of the wafer alignment table 10 so that the light receiving part panel 30 is inserted by inserting the screws 36 in the screw grooves. It can be fixed to the side wall of the wafer alignment table 10, it can be adjusted to be located at a height corresponding to the light emitting sensors (22, 24).

In addition, the two light receiving sensors are attached to the light receiving unit panel 30 by two fixing screws 32 and 34, respectively, and the screw grooves into which the fixing screws 32 and 34 are inserted are formed long in the left and right directions. Thus, since the screw groove is formed long in the left and right direction, the left and right positions of the light receiving sensor can be properly adjusted.

The reason why the position of the light receiving unit panel 30 is properly adjusted to match the position of the light emitting sensors 22 and 24 is that the flat zone of the wafer W is properly aligned. This is because it checks whether the signal is detected by the light receiving sensor.

However, the conventional wafer alignment device configured as described above has the following problems.

That is, the light receiving unit panel is fixed to the sidewall of the wafer alignment unit with two fixing screws, and two screws for fixing the light receiving unit panel and each fixing screw for attaching the light receiving sensor to the light receiving unit panel are formed long in the longitudinal direction and the left and right directions. Since it is inserted into the screw groove, the position of the light receiving unit panel may be changed by the vibration generated by loading the cassette on the wafer alignment table or by rotation of the guide roller and the alignment roller.

In this way, if the position of the light receiving panel is changed, the position of the light receiving sensor is also changed. Therefore, the flat zone of the wafer cannot be accurately detected, and an error occurs. It may cause cracking, and problems such as delayed work due to malfunctions occur.

Accordingly, the present invention has been made to solve the above problems, an object of the present invention is to securely support and fix the cassette by the support frame and the support plate when the light receiving panel is fixed to the wafer alignment stand, the wafer alignment stand The present invention provides a wafer alignment detecting device which does not change the position of the light receiving unit panel even on the vibration caused by the rotation of the guide roller and the alignment roller.

In order to achieve the above object, the present invention is a pair of alignment roller to rotate while being in contact with the lower end of the plurality of wafers vertically, parallel to the regular interval to match the flat zone of the wafer; A guide roller for guiding the wafer; A light emitting sensor for generating an optical signal to detect a flat zone of the wafer; And a light receiving sensor for receiving an optical signal generated by the light emitting sensor, wherein the light receiving sensor is provided on a light receiving panel that is height-adjustable, and an edge of the light receiving panel is supported by a support frame. Provided is a wafer alignment detection device, characterized in that supported.

Preferably, the light receiving unit panel is provided in parallel with one side wall of the wafer alignment unit on which the alignment roller and the guide roller are installed.

In addition, the support frame is formed integrally with at least one of the vertical rods, and further provided with a support plate installed in parallel with one side wall of the wafer alignment table.

In addition, the light receiving unit panel and the support plate are preferably fixed to one side wall of the wafer alignment table.

In addition, the support frame is preferably made of a horizontal rod and a vertical rod, the groove is formed in the interview portion of the horizontal rod or the vertical rod to be interviewed with the light receiving unit panel, the light receiving unit panel is formed, more preferably the support At least one groove is formed in the vertical rod of the frame to change the position of the horizontal rod by inserting both ends of the horizontal rod.

Hereinafter, an embodiment according to the present invention will be described with reference to the accompanying drawings.

Figure 2 is a schematic perspective view of a wafer alignment detection device according to an embodiment of the present invention, Figure 3 is a view showing a fixed state of the light receiving unit panel according to the present invention, Figure 4 is a coupling state of the horizontal bar and the vertical rod of the support frame It is sectional drawing shown. In Fig. 2, Fig. 3 and Fig. 4, the same components as those in Fig. 1 are denoted by the same reference numerals.

The wafer alignment detection device includes an alignment roller 15, a guide roller 17, light emitting sensors 22 and 24, a light receiving sensor, and the like.

The alignment roller 15 and the guide roller 17 are provided on the upper surface of the wafer alignment table 10, and the wafer on the top of the alignment roller 15 and the guide roller 17 to detect the flat zone of the wafer W. The loaded cassette is transferred and loaded.

The light emitting sensors 22 and 24 and the light receiving sensors for detecting the flat zone of the wafer W with the cassette 13 interposed therebetween are installed at the corresponding heights, and the light emitting sensors 22 and 24 are light emitting units. It is attached to the panel 20, and the light receiving sensor is attached to the light receiving part panel 30.

The light emitting panel 20 and the light receiving panel 30 are vertically installed with respect to the wafer alignment table 10, and the light emitting panel 20 is fixed to the wafer alignment table 10, while the light receiving panel 30 is installed. ) Is installed on the sidewall of the wafer alignment table 10 to enable height adjustment.

The light receiving unit panel 30 has two height adjusting screw grooves formed in the longitudinal direction so as to be coupled to the sidewall of the wafer alignment table 10. Thus, the light receiving unit panel 30 is inserted by inserting the screw 36 into the screw groove. It can be fixed to the side wall of the wafer alignment table 10, it can be adjusted to be located at a height corresponding to the light emitting sensors (22, 24).

In addition, the two light receiving sensors are attached to the light receiving unit panel 30 by two fixing screws 32 and 34, respectively, and a screw groove into which the fixing screws are inserted is formed long in the left and right direction. Thus, since the screw groove is formed long in the left and right direction, the left and right positions of the light receiving sensor can be properly adjusted.

The reason why the position of the light receiving unit panel 30 is properly adjusted to match the position of the light emitting sensors 22 and 24 is that the flat zone of the wafer W is properly aligned. This is because it checks whether the signal is detected by the light receiving sensor.

The present invention, unlike the prior art, to install the support frame 40 on the edge of the light receiving panel 30 in order to more firmly fix the light receiving panel 30 to the wafer alignment table 10, the support frame 40 This is fixed to the wafer alignment table 10 via the support plate 50.

That is, as shown in FIG. 3, horizontal bars 41 are installed at upper and lower edges of the light receiving unit panel 30, vertical bars 42 are installed at the left and right edges, and the vertical bars 42 are integral with the support plate 50. It is formed to be fixed to the side wall of the wafer alignment table (10).

The structure of the horizontal bar 41 and the vertical bar 42 will be described with reference to FIGS. 3 and 4. The horizontal bar 41 has a hollow inside, and the groove 41a is disposed at an interview portion with the light receiving panel 30. Is formed, and the light receiving part panel 30 is fitted into the groove 41a of the horizontal rod, and is fixed.

In addition, the vertical rod 42 is also hollow, and a groove is formed in the contact portion with the light receiving panel 30 so that the light receiving panel 30 is fitted into the groove and fixed. The vertical rod 42 is formed with a hole in which the horizontal rod 41 is inserted into the interview portion with both ends of the horizontal rod 41, and a plurality of holes are formed in the vertical direction to suit the height of the horizontal rod 41. Can be.

Since the edges of the light receiving unit panel 30 do not need to be fitted to both the horizontal bar 41 and the vertical bar 42, if the light receiving unit panel 30 can be firmly supported, either the horizontal bar 41 or the vertical bar 42 is provided. A groove may be formed in which the light receiving unit panel 30 can be inserted.

Insert both ends of the horizontal bar 41 into the holes of the vertical bar 42, and then the horizontal bar 41 and the vertical bar 42 with the fastening screw 43 so that the horizontal bar 41 and the vertical bar 42 can be more firmly fastened. ).

The support frame 40 may support the light receiver panel 30 more firmly by the support plate 50. That is, by fixing the support plate 50 formed integrally with the vertical rods 42 to the wafer alignment table 10 as shown in FIG. 3, the support frame 40 may fix and support the light receiving panel 30 more firmly. It becomes possible.

The horizontal bar 41 and the vertical bar 42 of the support frame 40 need not necessarily be fastened as shown in FIGS. 3 and 4, and the horizontal bar 41 and the vertical bar 42 are fastened with the fastening screw 43. Instead of simply inserting the horizontal bar 41 into the hole of the vertical bar 42, only the horizontal bar 41 may be fixed to the light receiving unit panel 30 with a fixing screw.

When the light receiving unit panel 30 is supported and fixed with the support frame 40 and the support plate 50 as described above, the vibration or alignment roller 15 generated when the cassette 13 is placed on the wafer alignment table 10 and Despite the vibration generated by the rotation of the guide roller 17, the light receiving unit panel 30 is not twisted or changed in position so that the flat zone of the wafer can be properly detected. Therefore, errors caused by incorrect detection of the flat zone of the wafer and cracks of the wafer can be prevented, and work loss due to device malfunction can be prevented.

Hereinafter, the effect | action of the wafer alignment detection apparatus of this invention comprised in this way is demonstrated.

5 is a cross sectional view taken along the line V of FIG. 2 when the wafer is aligned, and FIG. 6 is a cross sectional view taken along the line VI of FIG. 2 when the wafer is unaligned.

When the wafers W in the cassette 13 are aligned, the flat zone F of the wafer is directed downward as shown in FIG. 5, and the guide roller 17 is one side of the flat zone F of the wafer. It comes in contact with the end. In this case, even if the alignment roller 15 rotates in the direction of the arrow, the wafer W is prevented from rotating by interference between the flat zone F and the guide roller 17 to maintain the aligned state.

However, when the wafer W in the cassette 13 is in an unaligned state, as shown in FIG. 6, the guide roller 17 is brought into contact with the circumferential surface of the wafer W rather than the flat zone F of the wafer. do. In this case, when the alignment roller 15 rotates in the direction of the arrow, the unaligned wafer is rotated in contact with the guide roller 17 without interference of the guide roller 17, and the alignment roller 15 is predetermined. When rotating at an angle, the flat zone F of the wafer is caught by the guide roller 17.

As such, when the flat zone F of the wafer is caught by the guide roller 17, even if the alignment roller 15 rotates, the wafer W does not rotate and alignment is completed.

The wafer is aligned through the above-described process, and it is checked whether the wafer is properly aligned through the light paths of the light emitting sensors 22 and 24 and the light receiving sensor, which will be described with reference to FIGS. 7 and 8.

FIG. 7 is a schematic perspective view of a wafer alignment detection apparatus for explaining a method of confirming a wafer flat zone according to the present invention, and FIG. 8 is a cross-sectional view taken along line VII-VII of FIG. 7.

For convenience of description, a first alignment check point F1 and a second alignment check point F2 will be introduced. There may be one alignment check point or two or more alignment check points.

The first alignment check point (F1) is one of the virtual points that can confirm whether the flat zone (F) of the wafer is matched, is located in the alignment roller 15 is located at a predetermined distance of the lower end of the wafer flat zone (F), If the wafer flat zone F invades this point, it means that the wafer W is not aligned.

Also, for the same purpose as the first alignment check point F1, a second alignment check point F2 is defined in the alignment roller 15 and positioned at a predetermined distance at the lower end of the wafer flat zone F. Both the first alignment check point F1 and the second alignment check point F2 are spaced apart by the same distance from the lower end of the flat zone F of the aligned wafer.

The first alignment check point F1 and the second alignment check point F2 are detected by the first sensor unit and the second sensor unit including the light emitting sensors 22 and 24 and corresponding light receiving sensors.

That is, the first alignment check point F1 is detected by the first sensor part including the light emitting sensors 22 and 24 and the light receiving sensor, and the second sensor part including the light emitting sensors 22 and 24 and the light receiving sensor is second. The alignment check point (F2) is detected.

The alignment detection of the wafer W is performed by reading the signal from the light receiving sensor when the light signal is generated by the light emitting sensors 22 and 24 of the first sensor unit and the second sensor unit. At this time, it is preferable that the detection tolerance of the first alignment check point F1 and the second alignment check point F2 is +1.0 mm.

If the wafer W is aligned, the optical signals generated by the light emitting sensor 22 of the first sensor unit and the light emitting sensor 24 of the second sensor unit are simultaneously read by the light receiving sensor of the first sensor unit and the light receiving sensor of the second sensor unit. You lose.

On the other hand, if the flat zone of the wafer is not aligned, any one of the light receiving sensor of the first sensor unit and the light receiving sensor of the second sensor unit may not read the optical signal. This is because the optical path by the first sensor portion or the second sense portion is disturbed by the tilting of the flat zone of the wafer. If the wafer flat zone is not aligned, this can be alerted to the operator by an alarm or monitor.

In the above, the best embodiment has been disclosed in the drawings and the specification. Although specific terms have been used herein for the purpose of description, they are used only for the purpose of describing the present invention and are not intended to limit the meaning or the scope of the invention as set forth in the claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention should be defined by the technical spirit of the appended claims.

According to the present invention, by holding and fixing the light receiving unit panel with the support frame and the support plate, the light receiving unit panel despite the vibration generated when the cassette is placed on the wafer alignment table or the vibration generated by the rotation of the alignment roller or the guide roller. Since the flat zone of the wafer can be properly detected because there is no misalignment or change of position, it is possible to prevent wafer cracking caused by incorrect detection of the flat zone of the wafer, and to prevent errors and work losses due to malfunction of the device. have.

Claims (6)

A pair of alignment rollers that rotate while vertically contacting a plurality of wafer bottoms, and are arranged in parallel at regular intervals to match the flat zone of the wafer; A guide roller for guiding the wafer; A light emitting sensor for generating an optical signal to detect a flat zone of the wafer; And A light receiving sensor receiving an optical signal generated by the light emitting sensor; In the wafer alignment detection device comprising: The light receiving sensor is provided on the light receiving panel which can be adjusted in height, Wafer alignment detection device, characterized in that the edge of the light receiving panel is supported by a support frame. The method of claim 1, The light receiver panel, Wafer alignment detection device, characterized in that the alignment roller and the guide roller is installed in equilibrium with one side wall of the wafer alignment table. The method according to claim 1 or 2, And a support plate formed integrally with at least one of the vertical rods of the support frame and installed in parallel with one side wall of the wafer alignment table. The method of claim 3, wherein And the light receiving unit panel and the support plate are fixed to one side wall of the wafer alignment table. The method of claim 1, The support frame is composed of a horizontal bar and a vertical rod, the wafer alignment detection device, characterized in that a groove for inserting the light receiving panel is formed in the interview portion of the horizontal bar or the vertical rod to be interviewed with the light receiving unit panel. The method of claim 1, Wafer alignment detection device, characterized in that the vertical rod of the support frame is formed with one or more grooves for inserting both ends of the horizontal bar to change the position of the horizontal bar.

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