KR101601802B1 - Cleaning device for silicon wafer reuse and method - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus for a reusable silicon wafer and a cleaning method thereof, and more particularly to a cleaning apparatus for a reusable silicon wafer for cleaning a silicon adhesive applied on one surface of a silicon wafer using a high- . A storage part for recovering and storing the liquid sprayed on the reusable silicon wafer for compressing the liquid and converting the liquid into high pressure liquid; a high pressure liquid supply part for supplying high pressure liquid to the reusable silicon wafer, The injection robot portion for controlling the injection intensity of the high-pressure liquid according to the thickness of the impact absorbing layer so that the impact absorbing layer is peeled off, and the high pressure liquid sprayed on the reusable silicon wafer and the peeled impact absorbing layer disposed at the lower end of the adhesion table, And a recycling section for supplying the filtered liquid to the rear liquid recovery storage section.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a cleaning apparatus for cleaning a reusable silicon wafer,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus for a reusable silicon wafer and a cleaning method thereof, and more particularly to a cleaning apparatus for a reusable silicon wafer for cleaning a silicon adhesive applied on one surface of a silicon wafer using a high- .

Conventionally, as shown in FIG. 1, a method of adsorbing the silicon wafer 20 to the support disk 10 by using air pressure, and polishing by rotating the polishing machine 30 is used. In this case, the mechanical rotation of the polishing machine 30 and the support disk 10 becomes difficult to maintain a constant interval (height between the support disk and the polishing machine) due to thermal expansion and wear of the machine tool. When the height change between the support disk and the polishing machine occurs, there arises a problem that the silicon wafer is not polished to a constant thickness as shown in FIG. Therefore, there is a need for a technique capable of making the thickness of the polished surface constant by correcting the height of the polished surface due to the rotation of the polisher.

Prior Art Document 1: Korean Patent Laid-Open Publication No. 10-2004-0056177 (a polishing apparatus for a silicon wafer) Prior Art Document 2: JP-A-2013-175563 (Cleaning Apparatus of Wafer Stage and Cleaning Method of Wafer Stage)

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a method of manufacturing a silicon wafer by controlling the thickness to be polished against a change in height due to rotation during polishing, It is an object of the present invention to provide an invention capable of efficiently cleaning a reusable silicon wafer.

However, the objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

The above-described object of the present invention can be achieved by a method of manufacturing a reusable silicon wafer, comprising: a storage and production section for recovering and storing the liquid sprayed on a reusable silicon wafer, Pressure liquid sprayed on the surface of the wafer to control the injection intensity of the high-pressure liquid according to the thickness of the impact-absorbing layer so that the impact-absorbing layer applied on one surface of the wafer is peeled off, and a high-pressure liquid sprayed on the reusable silicon wafer and a peeled impact And a recycling section for collecting and filtering the absorbent layer and supplying the filtered liquid to the liquid recovery storage section.

The storage and formation unit may further include a liquid recovery and storage unit for recovering and storing the liquid sprayed onto the reusable silicon wafer and a pressure generator for compressing the liquid supplied from the liquid recovery and storage unit and converting the liquid into high pressure liquid .

In addition, the injection robot unit is provided with a spray portion for supplying a high-pressure liquid from the pressure generating portion and spraying a high-pressure liquid onto the impact absorbing layer applied to one surface of the reusable silicon wafer mounted on the contact table, And a controller for controlling the injection intensity of the high-pressure liquid according to the thickness of the impact absorbing layer.

The injection robot unit further includes a sensing unit arranged in parallel with the jetting unit to generate a sensing signal for sensing the thickness or the applied area of the impact absorbing layer. The control unit receives and analyzes the sensing signal from the sensing unit, And the injection intensity of the high-pressure liquid is controlled so that the impact-absorbing layer is peeled without being damaged.

The recycling unit includes a collecting unit disposed at the lower end of the contact table for collecting the high-pressure liquid sprayed on the reusable silicon wafer and the peeled impact absorbing layer, a filtering unit for filtering the liquid collected in the collecting unit and the impact absorbing layer, And a pumping unit for pumping the liquid to be supplied to the liquid recovery and storing unit.

Further, the impact absorbing layer is characterized by having elasticity and adhesiveness as a silicone adhesive.

And a solid storage portion for storing fine solid fine particles ejected together with the high pressure liquid sprayed onto the reusable silicon wafer, wherein the control portion is connected to the solid storage portion while checking the thickness of the impact absorbing layer and is supplied from the solid storage portion to the spray portion And controlling the amount of solid fine particles to be checked.

And a micro bubble generator connected to the liquid recovery reservoir and generating a micro bubble by receiving the stored liquid from the liquid recovery reservoir.

In addition, the controller may control the amount of fine particles or the size of the micro bubbles differently according to the cleaning time.

In addition, the control unit controls the injection nozzle so that the injection intensity is sprayed in the vertical direction with a narrow injection area when the initial thickness of the impact absorbing layer is thick under the same condition, and when the thickness of the impact absorbing layer is less than a predetermined thickness, And the injection nozzle is controlled so as to spray in a diagonal direction in which the spray intensity is weak while the area is wide.

Further, the reusable silicon wafer is a wafer on which no pattern is formed.

The above-described object of the present invention can also be achieved by a method of manufacturing a semiconductor device, comprising the steps of adhering a reusable silicon wafer coated on one side with an impact absorbing layer and an abrasive silicon wafer to be polished on one side with an impact absorbing layer, Separating the post-reuse silicon wafer from the polishing silicon wafer, and peeling off the solid-liquid repellent layer by spraying the solid-liquid impregnated layer on one side of the reusable silicon wafer, Is reused in the polishing of the abrasive silicon wafers.

Further, the impact absorbing layer is characterized by having elasticity and adhesiveness as a silicone adhesive.

The present invention is also characterized in that the thickness of the polishing surface of the polishing silicon wafer is made constant by allowing the height variation by the elasticity of the impact absorbing layer to be absorbed when thermal expansion or wear due to rotation during polishing of the polishing silicon wafer causes a change in height.

Further, the strength of the high-pressure liquid is controlled in accordance with the thickness of the impact absorbing layer and is injected.

Further, solid fine particles or microbubbles are injected together with the liquid.

It is further characterized in that the amount of fine grains or the size of micro bubbles is controlled according to the thickness of the impact absorbing layer.

Further, the size of the fine particles or the size of micro bubbles is controlled differently according to the time of cleaning.

When the thickness of the impact absorbing layer is equal to or less than a predetermined thickness, the injection area is relatively narrow. When the thickness of the impact absorbing layer is less than a predetermined thickness, So that the intensity is controlled to be injected in a weak diagonal direction.

According to the present invention as described above, there is an effect that the thickness to be polished during the polishing of the silicon wafer can be made constant.

According to the present invention, the silicon adhesive applied to the silicon wafer is peeled off with high-pressure water to efficiently clean the reusable silicon wafer, thereby making it possible to reuse the silicon wafer, thereby achieving cost reduction.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate preferred embodiments of the invention and, together with the description, serve to further the understanding of the technical idea of the invention, It should not be construed as limited.
1 is a schematic view for polishing a conventional silicon wafer,
FIG. 2 is a configuration diagram for polishing a silicon wafer according to the present invention,
FIG. 3 is a view showing that the thickness to be polished can be uniformly polished by absorbing a variation amount according to the height variation amount during rotation of the chuck and the polishing machine according to the present invention,
4 is a view showing a cleaning apparatus for a reusable silicon wafer according to the first embodiment of the present invention,
5 is a block diagram of a cleaning apparatus for a reusable silicon wafer according to the first embodiment of the present invention,
6 is a block diagram of a cleaning apparatus for a reusable silicon wafer according to a second embodiment of the present invention,
7 is a block diagram of a cleaning apparatus for a reusable silicon wafer according to a third embodiment of the present invention,
8 is a block diagram of a cleaning apparatus for a reusable silicon wafer according to a fourth embodiment of the present invention,
FIGS. 9 to 11 are views showing that the injection nozzles are injected at different angles according to the present invention,
12 is a diagram sequentially showing a cleaning method of a reusable silicon wafer according to the present invention.

Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. In addition, the embodiment described below does not unduly limit the content of the present invention described in the claims, and the entire structure described in this embodiment is not necessarily essential as the solution means of the present invention.

(Cleaning process system of reusable silicone ware)

The cleaning process system of the reusable silicon wafer according to the present invention includes a silicon wafer polishing apparatus for polishing the silicon wafer to a predetermined thickness and a cleaning apparatus for the reusable silicon wafer for cleaning the reusable silicon wafer polished through the silicon wafer polishing apparatus.

(Silicon wafer polishing apparatus)

In order to solve the problem that the polishing apparatus for polishing a reusable silicon wafer does not polish a uniform thickness during polishing of the reusable silicon wafer, the impact absorbing layer 210 is applied to the reusable silicon wafer 200 to polish the reusable silicon wafer 200 to a predetermined thickness The reusable silicon wafer 200 is reused for polishing the next abrasive silicon wafer 300 by allowing the impact absorbing layer 210 to be peeled off with a liquid. Hereinafter, a cleaning apparatus for a reusable silicon wafer according to the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, the reusable silicon wafer 200 is a silicon wafer on which no pattern is formed. In the present invention, the polishing silicon wafer 300 having the pattern formed thereon is polished to a predetermined thickness during polishing. . The reason why the reusable silicon wafer 200 is used is that the thermal expansion coefficient of the polishing silicon wafer 300 is the same as that of the polishing silicon wafer 300 when thermal expansion or abrasion due to rotation during polishing is used to minimize the change in height between the chuck 100 and the polishing machine 400 have. Accordingly, it is possible to minimize the problems as in the conventional FIG.

An impact-absorbing layer 210 is applied to the lower surface of the reusable silicon wafer 200 of the present invention. At this time, it is preferable to use the reusable silicon wafer 200 having the same thermal expansion coefficient as the abrasive silicon wafer 300.

As described above, by applying the impact absorbing layer 210, it is possible to easily absorb a change in force caused by thermal expansion and mechanical wear, or a change in height due to the inflow of particles generated during polishing.

The impact absorbing layer 210 may be formed of a soft silicone adhesive 210 and the silicone adhesive 210 may be elastic and tacky to easily absorb a change in pressure as shown in FIG. The wafer 300 can be polished to have a constant thickness. Such a silicone adhesive 210 is sticky and bonds the reusable silicon wafer 200 and the polishing silicon wafer 300 to each other.

When the reusable silicon wafer 200 and the abrasive silicon wafer 300 are rotated in the first direction by the rotation of the chuck 100 during the abrasion by the adhesion between the reusable silicon wafer 200 and the abrasive silicon wafer 300, The polishing pad 400 is rotated in the second direction opposite to the first direction to polish the lower surface of the polishing silicon wafer 300 in a flat manner.

The present invention is not limited thereto and only the reusable silicon wafer 200 and the abrasive silicon wafer 300 may be rotated and the abrasive machine 400 may not rotate and the silicon may be rotated not only by the rotational motion but also by the linear motion It is obvious that it can be polished.

The use of the reusable silicon wafer 200 having the same thermal expansion coefficient as described above and the application of the impact absorbing layer 210 enable processing of the polishing silicon wafer 300 having a constant thickness as shown in Fig.

(Cleaning apparatus for reusable silicon wafers)

As described so far, when the polishing of the polishing silicon wafer 300 is completed, the silicon adhesive 210 applied to the reusable silicon wafer 200 must be cleaned to polish another polishing silicon wafer 300.

Hereinafter, the configuration and function of the cleaning apparatus for a reusable silicon wafer according to various embodiments of the present invention will be described in detail with reference to FIGS. 4 to 11. FIG.

4 and 5, the apparatus for cleaning a reusable silicon wafer according to the first embodiment of the present invention includes a storage generator 500, a jetting robot unit 600, and a recycling unit 700.

The storage generator 500 recovers and stores the liquid sprayed on the reusable silicon wafer 200, compresses the liquid, and converts the liquid into a high-pressure liquid. The storage generation unit 500 includes a liquid recovery storage unit 510 and a pressure generation unit 520.

The liquid recovery / storage unit 510 recovers and stores the liquid sprayed onto the reusable silicon wafer 200. The liquid recovery and storage unit 510 includes a recovery line connection terminal connected to a recovery line for recovering liquid from the recycling unit 700, a storage space for storing liquid supplied through the recovery line, And a supply line connection terminal connected to a supply line for supplying the voltage to the unit 520.

In addition, the liquid recovery storage unit 510 may include a supplementary terminal connected to a supplementary line which can replenish liquid from the outside when the liquid to be recovered is insufficient.

The pressure generating unit 520 receives the stored liquid from the liquid recovery storage unit 510, compresses the liquid, and converts the liquid into high-pressure liquid. The pressure generating unit 520 may directly compress the liquid supplied through the supply line and convert the liquid into a high-pressure liquid, or may convert the liquid into a high-pressure liquid using the compressed gas. Thus, the high-pressure liquid generated through the pressure generating unit 520 is supplied to the jetting unit 610 through the jetting line.

Here, the pressure generating unit 520 may be any apparatus and method as long as it can compress the liquid and convert it into a high-pressure liquid.

The injection robot unit 600 receives the high pressure liquid from the storage generator 500 and receives the shock absorbing layer 210 so that the impact absorbing layer 210 applied on one surface of the reusable silicon wafer 200 mounted on the adhesion table 810 is peeled off. ), The injection intensity of the high-pressure liquid is controlled and injected. The jetting robot unit 600 may include a jetting unit 610 and a control unit 620.

The jetting section 610 receives the high pressure liquid from the pressure generating section 520 and ejects the high pressure liquid to the impact absorbing layer 210 applied to one surface of the reusable silicon wafer 200 mounted on the adhesion table 810. The jetting unit 610 includes a jetting nozzle 611 that receives high-pressure liquid through the jetting line and jetting toward the shock absorbing layer 210 and a nozzle arm 612 that operates to change the angle of the jetting nozzle 611 can do. The injection nozzle 611 is formed in various shapes, and the injection amount of the high-pressure liquid can be injected differently.

The control unit 620 controls the injection intensity of the high-pressure liquid according to the thickness of the impact absorbing layer 210 so as to peel the impact absorbing layer 210 without damaging the reusable silicon wafer 200. The controller 620 checks the thickness of the impact absorbing layer 210 and checks the amount of liquid supplied to the pressure generator 520 from the liquid recovery reservoir 510 by being connected to the liquid recovery reservoir 510, Pressure liquid to be injected from the jetting section 610 toward the impact absorbing layer 210 by checking the pressure of the high-pressure liquid supplied from the pressure generating section 520 to the jetting section 610, The injection intensity can be controlled. Accordingly, the impact absorbing layer 210 can be easily separated without damaging the reusable silicon wafer 200.

Here, the jet intensity can be generated by appropriately combining the pressure, injection amount, area, etc. of the high-pressure liquid.

The control unit 620 can control the injection intensity of the high-pressure liquid corresponding to the thickness of the impact absorbing layer 210 based on a predetermined injection look-up table (not shown). For example, when the thickness of the impact absorbing layer 210 is 0.1 mm or less, the pressure of the high-pressure liquid is 1000 bar, and when the thickness is 0.1 mm or more and 0.2 mm or less, the pressure of the high-pressure liquid is 1400 bar. That is, the control unit 620 sets the jetting intensity of the high-pressure liquid most suitable for removing the shock absorbing layer 210 to the jetting table in accordance with the thickness of the shock absorbing layer 210, and then adjusts the jetting intensity of the high- Can be controlled.

The recycling unit 700 collects and filters the high pressure liquid sprayed on the reusable silicon wafer 200 and the peeled shock absorbing layer 210 disposed at the lower end of the adhesion table 810, Thereby supplying the liquid. The recycling unit 700 may include a collecting unit 710, a filtering unit 720, and a pumping unit 730.

The collecting unit 710 collects the high pressure liquid sprayed on the reusable silicon wafer 200 and the peeled shock absorbing layer 210 disposed at the lower end of the adhesion table 810. The collecting unit 710 can easily emit the high pressure liquid separated from the reusable silicon wafer 200 and the impact absorbing layer 210 separated from the reusable silicon wafer 200 by being jetted from the jetting unit 610, So that the lower portion gradually becomes narrower so as to be collected. That is, the upper portion of the collecting portion 710 is formed to have a larger area than that of the adhesion table 810 and the lower portion of the collecting portion 710 is formed to have an area smaller than that of the adhesion table 810, ) Can easily be collected into one place without leaving the other.

Here, the high-pressure liquid is converted into a liquid in which the high pressure is extinguished after the impact absorbing layer 210 is sprayed.

The filtering unit 720 filters the liquid collected in the collecting unit 710 and the shock absorbing layer 210. The filtering unit 720 is configured to catch the foreign substance contained in the shock absorbing layer 210 and the liquid, and to pass only the liquid. The shock absorbing layer 210 and the foreign matter filtered by the filtering unit 720 are discharged to the outside.

Here, the filtering unit 720 may have any shape as long as it can pass the foreign matter and the shock absorbing layer 210 while passing the liquid. In addition, the filtering unit 720 may be disposed between the collecting unit 710 and the pumping unit 730 as long as the foreign substances or the like can be completely captured.

The pumping unit 730 pumps the filtered liquid from the filtering unit 720 and supplies the filtered liquid to the liquid recovery storage unit 510. The pumping unit 730 includes a high-pressure pump, and can pump the filtered liquid to be supplied to the liquid recovery reservoir 510 quickly.

Further, the adhesion table 810 for supporting the reusable silicon wafer 200 may be provided. The adhesion table 810 includes a driving unit 820 and a wafer chuck 830. The driving unit 820 can be operated through a table control program.

The driving unit 820 is disposed at the lower end or inside of the adhesion table 810 so as to rotate the reusable silicon wafer 200 fixed to the contact table 810 clockwise or counterclockwise according to the table control program can do. At this time, the driving unit 820 includes a motor that can rotate the contact table 810.

The driving unit 820 may operate so that the reusable silicon wafer 200 closely attached to the contact table 810 moves at a predetermined angle while rotating. Accordingly, it is possible to perform an operation such that the angle of the jetting part 610 to be injected is adjusted.

That is, the ejection robot unit 600 controls the ejection angle of the ejection nozzle 611 that is ejected while moving the ejection unit 610 to remove the silicone adhesive, which is the impact absorbing layer 210 applied to the reusable silicon wafer 200 And the angle at which the spray nozzle 611 is sprayed can be controlled differently by moving the reusable silicon wafer 200 fixed to the contact table 810 while the spray portion 610 is fixed.

The wafer chuck 830 can fix the reusable silicon wafer 200 when cleaning the reusable silicon wafer 200. That is, the reusable silicon wafer 200 can be adsorbed and fixed on the upper surface of the adhesion table 810 through the vacuum pressure. Thus, it is possible to prevent the reusable silicon wafer 200 from being arbitrarily moved in the adhesion table 810 while being cleaned.

Further, it is preferable that the adhesion table 810 is formed to have higher rigidity than the reusable silicon wafer 200. That is, when the high-pressure liquid is sprayed directly onto the reusable silicon wafer 200, a high pressure is directly applied to the thin reusable silicon wafer 200, so that the reusable silicon wafer 200 can be damaged. In order to prevent this, it is preferable that the adhesion table 810 has higher rigidity than the reusable silicon wafer 200.

Referring to FIG. 6, the apparatus for cleaning a reusable silicon wafer according to the second embodiment of the present invention includes a storage generator 500, a jetting robot unit 600, and a recycling unit 700.

In the apparatus for cleaning a reusable silicon wafer according to the second embodiment of the present invention, a description overlapping with the apparatus for cleaning a reusable silicon wafer according to the first embodiment of the present invention will be omitted.

The injection robot unit 600 includes a sensing unit 630 disposed in parallel with the jetting unit 610 to generate a sensing signal sensing the thickness or the applied area of the impact absorbing layer 210.

The sensing unit 630 may be disposed around the jetting unit 610 to easily sense the impact absorbing layer 210 or may be disposed on a side surface of the jetting robot unit 600.

In addition, the sensing unit 630 may be disposed in a plurality of ways as long as the shock absorbing layer 210 can be accurately sensed.

Thus, by sensing the impact absorbing layer 210, the thickness of the impact absorbing layer 210 or the area of the impact absorbing layer 210 applied to the reusable silicon wafer 200 can be more accurately checked.

The sensing unit 630 senses the impact absorbing layer 210 in real time and provides a sensing signal to the control unit 620 in real time to control the intensity of the injection, 210 to the control unit 620 at predetermined time intervals to control the injection intensity.

The control unit 620 can receive and analyze a sensing signal from the sensing unit 630 and control the injection intensity of the high-pressure liquid so that the reusable silicon wafer 200 is not damaged and the impact absorbing layer 210 is peeled. Since the control unit 620 receives the sensing signal in real time or at regular time intervals and can accurately check the thickness of the impact absorbing layer 210 and the applied area, it is possible to easily control the injection intensity of the high- have. Accordingly, the impact absorbing layer 210 can be removed without damaging the reusable silicon wafer 200.

7, the apparatus for cleaning a reusable silicon wafer according to the third embodiment of the present invention includes a storage generating unit 500, a solid storage unit 530, a jetting robot unit 600, and a recycling unit 700 .

In the apparatus for cleaning a reusable silicon wafer according to the third embodiment of the present invention, a description of the apparatus for cleaning a reusable silicon wafer according to the first and second embodiments of the present invention will be omitted.

The solid storage 530 stores fine solid fine particles which are injected into the reusable silicon wafer 200 together with the high pressure liquid sprayed thereon. The solid reservoir 530 includes a solid supply line connection terminal connected to a solid supply line for supplying solid fine particles to the jetting unit 610.

Here, the solid storage 530 is disposed at a higher position than the jetting unit 610, and the solid fine particles can be discharged to the jetting unit 610 through the solid supply line. Accordingly, the jetting section 610 can easily inject the solid fine particles together with the high-pressure liquid.

At this time, the solid fine particles may be formed within a range of 0.01 mm or more and 0.1 mm or less in diameter, injected together with the high-pressure liquid, collected in the recycling section 700, and then filtered.

In addition, the solid storage 530 can be separated and stored according to the size of the solid fine particles.

In addition, the solid fine particles may be formed in various shapes. Such solid fine grains may include silica sand and the like.

The jetting section 610 is connected to a solid supply line through which solid fine particles are supplied from the solid storage section 530. The injection unit 610 receives the high-pressure liquid and the solid fine particles and simultaneously injects the high-pressure liquid and the solid fine particles onto the impact absorbing layer 210 applied to one surface of the reusable silicon wafer 200 mounted on the adhesion table 810.

The control unit 620 checks the thickness of the impact absorbing layer 210 and checks the amount of the solid fine particles connected to the solid storing unit 530 and supplied from the solid storing unit 530 to the jetting unit 610. The control unit 620 checks the amount of the liquid and the pressure of the high-pressure liquid described in the first and second embodiments and controls the injection intensity of the high-pressure liquid while checking the amount of the solid fine particles, .

That is, the control unit 620 ejects the solid fine particles together with the high-pressure liquid, so that the impact absorbing layer 210 can be easily removed even if the amount of the liquid and the pressure of the high-pressure liquid are lowered. In this manner, by injecting the solid fine particles together, the impact absorbing layer 210 can be removed in various ways corresponding to the surrounding environment.

As described above, in the third embodiment of the present invention, the solid fine particles are sprayed on the impact absorbing layer 210 together with the high-pressure liquid, so that the impact absorbing layer 210 is removed from the reusable silicon wafer 200 in a shorter time As well as lowering the amount of liquid and the pressure of the high-pressure liquid.

8, the cleaning apparatus for a reusable silicon wafer according to the fourth embodiment of the present invention includes a storage generation unit 500, a micro bubble generation unit 540, a jetting robot unit 600, and a recycling unit 700 .

In the apparatus for cleaning a reusable silicon wafer according to the fourth embodiment of the present invention, a description of the apparatus for cleaning a reusable silicon wafer according to the first and second embodiments of the present invention will be omitted.

The micro bubble generator 540 is connected to the liquid recovery / storage unit 510 and receives the stored liquid from the liquid recovery / storage unit 510 to generate micro bubbles.

The micro bubble generator 540 can generate micro bubbles within a range of 40 mu m or more and 50 mu m or less in diameter by using a micro bubble nozzle after maintaining a predetermined temperature and a predetermined pressure to generate micro bubbles .

The micro bubble generator 540 receives the liquid through the supply line to generate micro bubbles, and supplies the generated micro bubbles to the jet unit 610 using a bubble line. The micro bubble generator 540 may include a bubble line connection terminal connected to the bubble line.

Here, although the micro bubble generator 540 is connected to the liquid recovery storage unit 510 to receive the liquid, the present invention is not limited thereto. Although not shown, the liquid may be supplied directly to the external rotor.

The micro bubble generator described so far typically includes a device capable of generating micro bubbles.

The jetting unit 610 is connected to the bubble line to which the micro bubble is supplied from the micro bubble generating unit 540. The injection unit 610 receives the high-pressure liquid and the micro bubble, and injects the high-pressure liquid and the micro bubble together to the impact absorbing layer 210 applied to one surface of the reusable silicon wafer 200 mounted on the adhesion table 810.

The control unit 620 checks the thickness of the impact absorbing layer 210 and checks the amount of microbubbles supplied from the microbubble generator 540 to the jet unit 610 in connection with the microbubble generator 540. The controller 620 checks the amount of the liquid and the pressure of the high-pressure liquid described in the first and second embodiments, and simultaneously controls the injection intensity of the high-pressure liquid while checking the microbubbles. have.

As described above, in the fourth embodiment of the present invention, the microbubble is sprayed onto the impact absorbing layer 210 together with the high-pressure liquid, so that the impact absorbing layer 210 can be cleanly and quickly removed from the reusable silicon wafer 200 .

Although the solid fine particles and the micro bubbles have been described so far, the solid fine particles and the micro bubbles may be injected at the same time as the high pressure liquid, and may be sequentially injected.

9 and 10, even if the intensity of the high-pressure liquid to be injected is the same, the injection intensity and the injection area can be different according to the angle of the injection nozzle 611. [ In other words, since the spray angle of the spray nozzle 611 arranged in the vertical direction shown in FIG. 9 is different from the spray angle of the spray nozzle 611 arranged in the diagonal direction shown in FIG. 10, the spray intensity and the spray area can be different have.

That is, the jetting nozzles 611 disposed in the vertical direction and injected in the horizontal direction are higher in jet intensity than the jetting nozzles 611 jetted in the horizontal direction, and the jetting area, which is an area contacting the impact absorbing layer 210, may be narrower .

Accordingly, even under the same conditions of the pressure of the liquid to be sprayed and the consumption amount of the liquid, the spray nozzle 611 is controlled to be cleaned so that the spray intensity is sprayed in the vertical direction with a narrow spray area at the time of initial cleaning, It is possible to clean the reusable silicon wafer 200 so as not to be damaged by controlling the injection nozzle 611 so that the ejection nozzle 611 is sprayed in a horizontal direction with a weak spray intensity while the spray area is wide.

In the embodiment shown in FIG. 10, the injection angle is controlled by controlling the injection nozzle. However, the present invention is not limited to this. As shown in FIG. 11, You may.

(Cleaning method of reusable silicon wafer)

The cleaning method of the reusable silicon wafer according to the present invention will be described with reference to Fig. 12 showing the method of cleaning the silicon adhesive which is the shock absorbing layer after polishing the abrasive silicon wafer.

Referring to FIG. 9, first, a silicon adhesive is applied to one surface of a reusable silicon wafer having the same thermal expansion coefficient as that of a polished silicon wafer to be polished to form an impact absorbing layer (S100). The reusable silicon wafer and the polished silicon wafer to be polished are bonded by a silicone adhesive (S200).

The lower surface of the polishing silicon wafer is polished to a constant thickness by rotation of the chuck and the polishing machine (S300). At this time, even when the height of the chuck and the polishing machine changes due to the use of the silicon wafer having the same thermal expansion coefficient and the silicon adhesive, the thickness to be polished is different from that of the prior art as shown in Fig. 1, The lower surface can be polished.

When the lower surface of the polishing silicon wafer is polished to a predetermined thickness, the polished silicon wafer and the reusable silicon wafer are separated. On one side of the separated reusable silicon wafer, a silicone adhesive is applied.

Thereafter, the liquid is sprayed onto the reusable silicon wafer by using the ejection robot unit to peel off the silicone adhesive applied to the reusable silicon wafer (S400). The peeled reusable silicon wafer can be reused in the polishing of a polished silicon wafer requiring subsequent polishing. Therefore, the reuse silicon wafers can be reused to achieve a cost saving effect.

Here, the pressure of the high-pressure liquid injected through the injection robot unit is not less than 1000 bar and not more than 4000 bar, and the injection amount of the high-pressure liquid can be varied depending on the condition within a range of 4 kg to 40 kg per hour. However, the numerical range can be variously varied according to the coating thickness of the above-described silicone adhesive and the state of the reusable silicon wafer.

At this time, when the pressure of the high-pressure liquid is 1000 bar or less, the silicone adhesive does not peel off. If the pressure is 4000 bar or more, the surface of the reusable silicon wafer may be damaged. Accordingly, efficient wafer cleaning can be performed at a pressure of the high-pressure liquid of 1000 bar to 4000 bar or less.

That is, when the pressure of the weakest high-pressure liquid is 1000 kg, the wafer clean can be performed with the least amount of force when 4 kg / h of injection of high-pressure liquid per hour is used, and the pressure of high pressure liquid is 4000 Bar, and the injection amount of high pressure liquid per hour is 40 kg / The wafer clean can be done with the strongest force.

Here, since the high-pressure liquid is sprayed at a pressure of about 4000 bar or less, the reusable silicon wafer is adsorbed and fixed by the adhesion table, so that it can be cleaned without damaging the reusable silicon wafer even if it is sprayed directly onto the reusable silicon wafer.

In this embodiment, the high-pressure liquid is sprayed to remove the silicone adhesive. However, by additionally spraying solid fine particles or microbubbles together with the liquid, the silicone adhesive can be rapidly removed from the reusable silicon wafer, and can be cleanly removed.

Further, it is possible to remove the silicone adhesive by ejecting the liquid onto the reusable silicon wafer by using the ejection robot unit, and varying the size and amount of the solid fine particles or the micro bubble to be ejected according to the sensing signal.

In addition, the size and amount of the solid fine particles or micro bubbles to be sprayed to remove the silicone adhesive can be controlled over time by spraying the liquid onto the reusable silicon wafer using the injection robot unit.

That is, it can be controlled so that the size of the solid fine particles and the time of spraying the microbubbles gradually decrease. As described above, when the amount of the silicone adhesive applied is relatively large, relatively large solid fine particles and a large number of microbubbles are sprayed to quickly remove the silicone adhesive applied to the reusable silicon wafer. When the amount of the silicone adhesive is small, It is possible to remove the silicon adhesive remaining on the reusable silicon wafer while spraying the microbubbles with the particles to prevent the reusable silicon wafer from being broken.

Therefore, the reusable silicon wafer can be efficiently cleaned.

Although the present invention has been described with reference to the embodiment thereof, the present invention is not limited thereto, and various modifications and applications are possible. In other words, those skilled in the art can easily understand that many variations are possible without departing from the gist of the present invention.

10: Support disk
20: Polished silicon wafer
30: Grinding machine
100: Chuck
200: Reusable Silicon Wafer
210: Impact absorbing layer (silicone adhesive)
300: Polished silicon wafer
400: Grinding machine
500:
510: a liquid recovery /
520: pressure generating portion
530: solid storage
540: micro bubble generator
600: injection robot part
610:
611: Spray nozzle
612: nozzle arm
620:
700: Recycling Department
710:
720:
730:
810: Contact table
820:
830: wafer chuck

Claims (19)

delete delete delete delete delete delete delete delete delete delete delete Bonding a reusable silicon wafer coated on one side of the impact absorbing layer and an abrasive silicon wafer polished on one side with an impact absorbing layer;
Polishing one side of the polishing silicon wafer;
Separating the reusable silicon wafer and the polishing silicon wafer after completion of polishing; And
And spraying a high-pressure liquid onto the impact-absorbing layer applied to one surface of the reusable silicon wafer,
The impact absorbing layer has elasticity and adhesiveness as a silicone adhesive,
The pressure of the high-pressure liquid is varied within a range of from 4000 bar to 1000 bar, and the injection amount is varied from 4 kg to 40 kg per hour to spray the high-pressure liquid from the reusable silicon wafer, Wherein the reusable silicon wafer is reused for wafer polishing.
delete 13. The method of claim 12,
When polished silicon wafers are polished
Wherein the thickness of the abrasive surface of the abrasive silicon wafer is made constant by absorbing a change in height by the elasticity of the impact absorbing layer when a change in height is caused by thermal expansion or wear due to rotation.
13. The method of claim 12,
Wherein the strength of the high-pressure liquid is controlled and injected according to the thickness of the impact absorbing layer.
13. The method of claim 12,
Wherein solid fine particles or microbubbles are sprayed together with the high-pressure liquid.
13. The method of claim 12,
Wherein the amount of fine grains and the size of micro bubbles are controlled according to the thickness of the impact absorbing layer.
17. The method of claim 16,
Wherein the size of the solid fine particles or the size of the microbubbles is controlled differently according to the cleaning time.
13. The method of claim 12,
The thickness of the impact absorbing layer is controlled so as to be injected in a vertical direction with a narrow injection area when the initial thickness of the impact absorbing layer is thick. When the thickness of the impact absorbing layer is less than a predetermined thickness, So that the intensity of the laser beam is controlled so that the intensity is injected in a diagonal direction with a weak intensity.

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