Wafer sampling recovery and cleaning system and wafer sampling recovery and cleaning method using the same

Abstract

The present invention relates to a system for recovering a sampling solution after sampling a wafer and cleaning the remaining sampling solution. The wafer sampling recovery and cleaning system and the wafer sampling recovery and cleaning method using the same of the present invention include a cleaning unit that cleans the surface of the recovery unit that recovers the sampling solution from the wafer, thereby improving the accuracy of the wafer sampling process.

Description

[Technical Field]

[0001] The present invention relates to a system for recovering sampling solution and cleaning remaining sampling solution after sampling a wafer. [Background technology]

[0002] Core processes in the semiconductor and display industries require the use of a wide variety of hazardous gases, including acidic gases such as fluorine, chlorine, bromine, nitric acid, and sulfuric acid, basic gases such as ammonia and amines, organic compounds, metallic substances such as copper, aluminum, and silicon, and dopant substances such as phosphorus and boron. Generally, these gases are toxic and have strong oxidizing properties, which can cause pattern abnormalities and surface overoxidation in products, resulting in product defects.

[0003] In semiconductors, the term "wafer" almost always refers to a silicon wafer, a thin silicon plate that serves as the base for fabricating semiconductor integrated circuits. Wafers are made by thinly slicing single-crystal silicon with a purity of 99.9999999% and smoothing the surface. It goes without saying that the surface of a wafer must be free of defects and contamination, and a high degree of flatness is required, as these can affect the precision of the circuit. Recently, disc-shaped wafers with a thickness of 0.3 mm and a diameter of 15 to 30 cm are being used.

[0004] After assembly and testing, the wafer is cut into individual chips and used as a completed integrated circuit. Before being used as an integrated circuit, the wafer undergoes processes such as patterning, etching, and ion implantation, and is then housed in a transport enclosure where it is either transported for the next process or left in a waiting state. However, the wafer is exposed to a large amount of chemicals during these processes, which can cause chemical contamination, and the inside of the transport enclosure can be contaminated by the contaminated wafer.

[0005] In this way, if wafers are stored in a contaminated transport enclosure for a long period of time and the transport enclosure becomes contaminated above a certain concentration level, it can have a negative effect on the wafers and cause product defects. Therefore, in order to improve the quality of wafer production, a sampling process that quickly and accurately measures not only the gas contamination inside the transport enclosure but also the contamination level on the wafer surface is very important.

[0006] Therefore, in the conventional technology, in order to check for contaminants on the wafer surface, a sampling solution is sprayed onto the wafer surface, and the sampling solution is collected and analyzed. However, this method has a problem in that some contaminants remain in the collection device that collects and stores the sampling solution during the collection process, which can contaminate the collection device itself. This significantly reduces the accuracy of wafer sampling, and a need for a method to solve this problem is emerging. Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been devised to solve the above-mentioned problems, and aims to provide a wafer sampling recovery and cleaning system that can improve the accuracy of the wafer sampling process by including a cleaning unit that cleans the surface of the recovery unit that recovers the wafer sampling solution, and a wafer sampling recovery and cleaning method using the same. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, one embodiment of the present invention provides a wafer sampling recovery and cleaning system that is applicable to a wafer sampling device that includes a mounting part on one side of which a wafer is placed and which rotates the wafer, and a sampling nozzle that sprays a sampling solution onto the surface of the wafer, and is characterized by including a recovery part that is fixed to the mounting part and arranged along the outer edge of the wafer to recover the sampling solution from the top surface of the wafer, and a drain part that receives the sampling solution from the recovery part and discharges it to the outside.

[0009] The collection unit is characterized by including a sampling solution storage unit, which is a space of a predetermined depth in which the sampling solution is stored, and a first housing including a blocking wall disposed on one side of the sampling solution storage unit and extending vertically from the sampling solution storage unit.

[0010] The device further includes a cleaning unit that sprays a cleaning solution into the collection unit to clean the remaining sampling solution, and the cleaning unit includes a cleaning solution storage unit that is a space formed at a predetermined depth in the first housing, and a second housing that is connected to the top of the first housing, and the second housing includes a cover unit that is formed to cover the front of the top of the cleaning solution storage unit.

[0011] The second housing includes a flush flow rate adjusting portion that extends from the cover portion, surrounds the upper end of the blocking wall, and is spaced a predetermined distance from the upper end of the blocking wall.

[0012] The second housing includes a height adjusting portion for adjusting the height of the cleaning flow rate adjusting portion, and the height adjusting portion is a bolt that penetrates the second housing and the first housing.

[0013] The blocking wall is disposed so that one surface thereof faces the wafer and the sampling solution storage unit, and the one surface of the blocking wall is formed at a predetermined angle from the vertical direction.

[0014] The sampling solution storage unit has another side connected to the drain unit, and the other side is formed to be inclined at a predetermined angle from the vertical direction.

[0015] The cleaning unit may include at least one wall cleaning nozzle that supplies a cleaning solution to the blocking wall, and the wall cleaning nozzle may spray the cleaning solution directly onto the blocking wall.

[0016] The cleaning unit may also include at least one wall cleaning nozzle for supplying a cleaning solution to the blocking wall, and the wall cleaning nozzle may spray the cleaning solution onto the outermost surface of the wafer.

[0017] The spray direction of the wall surface cleaning nozzle is not perpendicular to the spray direction of the sampling nozzle, but is at a predetermined angle.

[0018] A wafer sampling recovery and cleaning method according to one embodiment of the present invention is a wafer sampling recovery and cleaning method using a wafer sampling recovery and cleaning system, and is characterized by including the steps of (a) receiving a wafer sampling solution through a recovery unit, (b) cleaning the blocking wall of the recovery unit through a cleaning unit, and (c) discharging the sampling solution to the outside through a drain unit.

[0019] The step (b) includes at least one of the steps of (b1) determining the spray direction of the cleaning solution and (b2) determining the spray strength of the cleaning solution, and is characterized by including, following the step (b1) or the step (b2), a step (b3) of supplying the cleaning solution to the blocking wall.

[0020] The (b1) step further includes (b11) a step of providing at least one wall cleaning nozzle for supplying a cleaning solution to the blocking wall, and (b12) a step of adjusting the spray direction of the wall cleaning nozzle toward the blocking wall when the expected adhesion strength of particles on the blocking wall is higher than a predetermined reference adhesion strength, and (b13) a step of adjusting the spray direction of the wall cleaning nozzle toward the wafer when the expected adhesion strength of particles on the blocking wall is lower than or equal to the predetermined reference adhesion strength.

[0021] In addition, the (b2) step includes (b21) a step of fastening the second housing to the top of the first housing, and (b22) a step of injecting the cleaning solution into the cleaning solution storage section and supplying it to the blocking wall, and if the sampling solution in the blocking wall remains above the reference value, (b23) a step of adjusting the height of the second housing downward via the height adjustment section. [Effects of the Invention]

[0022] The wafer sampling recovery and cleaning system of the present invention configured as described above and the wafer sampling recovery and cleaning method using the same have the effect of improving the accuracy of the wafer sampling process by including a cleaning section that cleans the surface of the recovery section that recovers the sampling solution from the wafer. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a schematic diagram of a wafer sampling retrieval and cleaning system of the present invention. [Figure 2] FIG. 1 is a schematic diagram illustrating a first embodiment of a cleaning unit of the present invention. [Figure 3] FIG. 4 is a schematic view illustrating a second embodiment of the cleaning unit of the present invention. [Figure 4] FIG. 10 is a schematic view illustrating a third embodiment of the cleaning unit of the present invention. [Figure 5] 1 is a flow chart illustrating the wafer sampling retrieval and cleaning method of the present invention. [Figure 6]10 is a flowchart illustrating detailed steps of the barrier wall cleaning step of the present invention. [Figure 7] 4 is a flowchart illustrating detailed steps of the cleaning liquid direction determination step of the present invention. [Figure 8] 4 is a flowchart illustrating detailed steps of the cleaning solution strength determination step of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] The technical concept of the present invention will be described in more detail below with reference to the accompanying drawings. Before that, the terms and words used in the specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts that are consistent with the technical concept of the present invention, based on the principle that the inventors can appropriately define the concepts of terms in order to best describe their inventions.

[0025] The basic configuration of a wafer sampling, recovery and cleaning system 1000 of the present invention will be described below with reference to FIG.

[0026] The present invention relates to a wafer sampling recovery and cleaning system 1000 applicable to a wafer W sampling device including a mounting part C on one side of which a wafer W is mounted and which rotates the wafer W, and a sampling nozzle N which sprays a sampling solution onto the surface of the wafer W. The wafer sampling recovery and cleaning system 1000 of the present invention may include a recovery part 100 which recovers a solution sampled from the surface of the wafer W. The recovery part 100 may be fixed to the mounting part C and rotate together with the mounting part C when the mounting part C rotates. Alternatively, the recovery part 100 may be fixed to the mounting part C and formed as a separate part from the part of the mounting part C that rotates the wafer W, and may maintain a fixed position regardless of the rotation of the wafer W. The recovery part 100 is arranged along the outer edge of the wafer W and can recover the sampling solution scattered on the top surface of the wafer W due to the centrifugal force of the rotating wafer W.

[0027] The collecting unit 100 may include a first housing 110 including a sampling solution storage unit 111, which is a space of a predetermined depth in which the sampling solution is stored, and a blocking wall 112 disposed on one side of the sampling solution storage unit 111 and extending vertically from the sampling solution storage unit 111. The sampling solution storage unit 111 and the blocking wall 112 may be formed as a single component. The maximum vertical height of the blocking wall 112 may be higher than the height of the wafer W attached to the mounting unit C. This allows droplets of the sampling solution scattering from the outer edge of the wafer W to collide with the blocking wall 112 and be stored in the sampling solution storage unit 111.

[0028] The wafer sampling, recovery, and cleaning system 1000 of the present invention may also include a drain unit 200. The drain unit 200 may receive the sampling solution from the recovery unit 100 and discharge it to the outside. The discharged sampling solution may be analyzed to determine whether or not contaminants are present on the surface of the wafer W. The sampling solution is preferably stored in the recovery unit 100 before being discharged to the outside via the drain unit 200.

[0029] The wafer sampling recovery and cleaning system 1000 of the present invention may also include a cleaning unit 300. The cleaning unit 300 sprays a cleaning solution onto the recovery unit 100 to clean the sampling solution remaining in the recovery unit 100. The cleaning solution may be ultrapure water or hot UPW. The inclusion of the cleaning unit 300 allows the surface of the recovery unit 100 to be kept clean, thereby improving the accuracy of analyzing the sampling solution. More specifically, when contaminants contained in the sampling solution settle in the sampling solution storage unit 111 or the sampling solution splashes and adheres to the blocking wall 112, the cleaning unit 300 cleans the surface of the recovery unit 100 through the cleaning unit 300, thereby improving the accuracy of analyzing the sampling solution.

[0030] Furthermore, the blocking wall 112 may be disposed such that one surface faces the wafer W and the sampling solution storage unit 111. As a result, when the sampling solution splashes from the surface of the wafer W, the sampling solution collides with the blocking wall 112 and can be collected in the sampling solution storage unit 111. More specifically, one surface of the blocking wall 112 may be formed to be inclined at a predetermined angle from the vertical direction. As a result, the sampling solution that collides with the blocking wall 112 and turns into droplets can be guided to flow along the inclined surface into the sampling solution storage unit 111.

[0031] In addition, the sampling solution storage unit 111 may have the other side connected to the drain unit 200 and the other side inclined at a predetermined angle from the vertical direction. That is, as shown in Fig. 1, the sampling solution storage unit 111 may be designed so that the internal cross-sectional area increases from the bottom to the top in the vertical direction. This can minimize the sedimentation of contaminants contained in the sampling solution on the bottom surface of the sampling solution storage unit 111.

[0032] Hereinafter, a first embodiment of the cleaning unit 300 of the present invention will be described in more detail with reference to FIG.

[0033] 2, the cleaning unit 300 may include a cleaning solution storage unit 310, which is a space formed at a predetermined depth in the first housing 110, and a second housing 320 coupled to the upper part of the first housing 110. The second housing 320 may include a cover unit 321 formed to cover the front surface of the upper part of the cleaning solution storage unit 310. As a result, the cleaning solution may be stored in a space surrounded by the cleaning solution storage unit 310, the cover unit 321, and the blocking wall 112. The cleaning solution storage unit 310 may be connected to a pump that provides the cleaning solution.

[0034] In addition, second housing 320 may include a cleaning flow rate adjuster 322 that extends from cover 321, surrounds the upper end of blocking wall 112, and is spaced a predetermined distance from the upper end of blocking wall 112. As a result, when cleaning solution is injected into cleaning solution storage 310 using a pump or the like and fills the space surrounded by cleaning solution storage 310, cover 321, and blocking wall 112, the overflowing cleaning solution leaks through the gap between cleaning flow rate adjuster 322 and blocking wall 112, thereby cleaning blocking wall 112.

[0035] Furthermore, second housing 320 includes a height adjustment unit 323 that adjusts the height of cleaning flow rate adjustment unit 322, and height adjustment unit 323 may be a bolt that penetrates second housing 320 and first housing 110. When the height of second housing 320 is adjusted by height adjustment unit 323, the distance between cleaning flow rate adjustment unit 322 and blocking wall 112 may be adjusted, thereby determining the flow rate of the cleaning solution. That is, assuming that cleaning solution is injected at a predetermined flow rate using a pump or the like, the longer the distance between cleaning flow rate adjustment unit 322 and blocking wall 112, the slower the flow rate may be, and the shorter the distance, the faster the flow rate may be (the spray intensity may be greater).

[0036] Hereinafter, the second embodiment of the cleaning unit 300 will be described in more detail with reference to FIG.

[0037] 3, the cleaning unit 300 may include at least one wall cleaning nozzle 330 that supplies a cleaning solution to the barrier wall 112. In a second embodiment of the cleaning unit 300, the wall cleaning nozzle 330 can spray the cleaning solution directly onto the barrier wall 112. This allows contaminants adhering to the surface of the barrier wall 112 to be directly cleaned with the cleaning solution. Here, the cleaning intensity can be easily adjusted by adjusting the spray intensity of the wall cleaning nozzle 330.

[0038] Hereinafter, the second embodiment of the cleaning unit 300 will be described in more detail with reference to FIG.

[0039] 4, the cleaning unit 300 may include at least one wall cleaning nozzle 330 that supplies a cleaning solution to the blocking wall 112. In the third embodiment of the cleaning unit 300, the wall cleaning nozzle 330 may spray the cleaning solution onto the outermost surface of the wafer W. As a result, the sampling solution and the cleaning solution on the wafer W are both scattered by centrifugal force, cleaning the blocking wall 112. As a result, damage to the blocking wall 112 may be minimized and contaminants on the blocking wall 112 may be removed.

[0040] Here, the spray direction of the wall cleaning nozzle 330 may be at a predetermined angle other than perpendicular to the spray direction of the sampling nozzle N. While the sampling nozzle N generally sprays the sampling solution in a direction perpendicular to the surface of the wafer W, the wall cleaning nozzle 330 may spray the cleaning solution in a direction at a predetermined inclination angle other than perpendicular to the surface of the wafer W in order to maximize scattering efficiency or in consideration of the arrangement of the nozzle and the pump. This maximizes cleaning efficiency.

[0041] The wafer sampling recovery and cleaning method of the present invention will be described below with reference to FIGS.

[0042] As shown in FIG. 5, the wafer sampling recovery and cleaning method using the wafer sampling recovery and cleaning system 1000 includes the steps of (a) receiving a wafer W sampling solution through the recovery unit 100, (b) cleaning the blocking wall 112 of the recovery unit 100 through the cleaning unit 300, and (c) discharging the sampling solution to the outside through the drain unit 200. In step (a), the recovery unit 100 is disposed along the outer edge of the wafer W and can recover the sampling solution scattered on the upper surface of the wafer W due to centrifugal force when the wafer W rotates. In step (c), the drain unit 200 is connected to the sampling solution storage unit 111 and can receive and discharge the sampling solution when a predetermined amount of sampling solution is stored in the sampling solution storage unit 111. The discharged sampling solution can be analyzed to determine whether contaminants are present on the surface of the wafer W. The sampling solution is preferably stored in the recovery unit 100 before being discharged to the outside through the drain unit 200.

[0043] Here, as shown in FIG. 6, step (b) may include at least one of steps (b1) determining the spray direction of the cleaning solution and (b2) determining the spray strength of the cleaning solution, and may include step (b3) supplying the cleaning solution to the blocking wall 112 following step (b1) or (b2).

[0044] 7, step (b1) may include (b11) providing at least one wall cleaning nozzle 330 for supplying a cleaning solution to the barrier wall 112, and (b12) adjusting the spray direction of the wall cleaning nozzle 330 toward the barrier wall 112 when the predicted adhesion strength of particles on the barrier wall 112 is higher than a predetermined reference adhesion strength. This allows contaminants adhering to the surface of the barrier wall 112 to be directly cleaned using the cleaning solution. In this case, the cleaning strength can be easily adjusted by adjusting the spray strength of the wall cleaning nozzle 330.

[0045] Also, when the predicted adhesion strength of particles on the barrier wall 112 is equal to or lower than a predetermined reference adhesion strength, the method may include a step (b13) of adjusting the spray direction of the wall cleaning nozzle 330 toward the wafer W. This causes both the sampling solution and the cleaning solution on the wafer W to be scattered by centrifugal force, thereby cleaning the barrier wall 112. This minimizes damage to the barrier wall 112 and removes contaminants on the barrier wall 112. Here, the method of adjusting the spray direction of the wall cleaning nozzle 330 in steps (b12) and (b13) may be manual or automatically adjusted in connection with a controller.

[0046] 8, step (b2) may include steps (b21) fastening the second housing 320 to the top of the first housing 110, and (b22) injecting the cleaning solution into the cleaning solution storage unit 310 and initially supplying it to the blocking wall 112. More specifically, when the cleaning solution is injected into the cleaning solution storage unit 310 using a pump or the like and the cleaning solution fills the space surrounded by the cleaning solution storage unit 310, the cover unit 321, and the blocking wall 112, the overflowing cleaning solution leaks through the gap between the cleaning flow rate adjuster 322 and the blocking wall 112 and can clean the blocking wall 112.

[0047] Here, if the sampling solution remaining in the blocking wall 112 is equal to or greater than the reference value after step (b22), the strength of the cleaning solution is too low, so step (b23) of adjusting the height of the second housing 320 downward using the height adjuster 323 may be included. The height adjuster 323 may be a bolt that penetrates the second housing 320 and the first housing 110. This shortens the separation distance between the cleaning flow rate adjuster 322 and the blocking wall 112, which may increase the flow rate (increase the spray strength).

[0048] The technical concept of the present invention should not be construed as being limited to the above-described embodiments. Needless to say, the scope of application is varied, and various modifications may be made by those skilled in the art without departing from the gist of the present invention as claimed in the claims. Therefore, such improvements and modifications, as long as they are obvious to those skilled in the art, belong to the scope of protection of the present invention.

Claims

1. A wafer sampling recovery and cleaning system applicable to a wafer sampling device including a wafer mounting unit on one side of which a wafer is mounted and which rotates the wafer, and a sampling nozzle which sprays a sampling solution onto the surface of the wafer, a recovery unit fixed to the mounting unit, arranged along the outer edge of the wafer, and configured to recover a sampling solution from the upper surface of the wafer; a drain unit that receives the sampling solution from the recovery unit and discharges it to the outside.

2. The recovery unit includes: a sampling solution storage section which is a space of a predetermined depth in which the sampling solution is stored; 2. The wafer sampling, recovery and cleaning system of claim 1, further comprising: a first housing including a blocking wall disposed on one side of the sampling solution storage section and extending vertically from the sampling solution storage section.

3. The collecting unit further includes a washing unit that injects a washing solution into the collecting unit to wash away remaining sampling solution; The cleaning unit includes: a cleaning solution storage section, which is a space formed in the first housing at a predetermined depth; a second housing coupled to an upper portion of the first housing, The second housing includes:

3. The wafer sampling, recovery and cleaning system of claim 2, further comprising a cover formed to cover a front surface of an upper portion of the cleaning solution storage unit.

4. The second housing includes: extending from the cover portion; 4. The wafer sampling, recovery and cleaning system according to claim 3, further comprising a cleaning flow rate adjusting unit that surrounds the upper end of the blocking wall and is spaced a predetermined distance from the upper end of the blocking wall.

5. The second housing includes: a height adjusting unit for adjusting the height of the cleaning flow rate adjusting unit; The height adjustment unit is 5. The wafer sampling, retrieval and cleaning system of claim 4, wherein the bolt penetrates through the second housing and the first housing.

6. The blocking wall is one surface of which is disposed so as to face the wafer and the sampling solution storage unit; 3. The wafer sampling, recovery and cleaning system according to claim 2, wherein one surface of the blocking wall is inclined at a predetermined angle from the vertical direction.

7. The sampling solution storage unit includes: The other side is connected to the drain portion, 3. The wafer sampling, recovery and cleaning system according to claim 2, wherein the other side surface is formed at a predetermined angle from the vertical direction.

8. The cleaning unit includes: at least one wall washing nozzle for supplying a cleaning solution to the blocking wall; The wafer sampling, recovery and cleaning system according to claim 2 , wherein the wall cleaning nozzle directly sprays the cleaning solution onto the blocking wall.

9. The cleaning unit includes: at least one wall washing nozzle for supplying a cleaning solution to the blocking wall; The wafer sampling, recovery and cleaning system of claim 2 , wherein the wall cleaning nozzles spray a cleaning solution onto the outermost surface of the wafer.

10. The spray direction of the wall cleaning nozzle is 10. The wafer sampling, recovery and cleaning system according to claim 9, wherein the sampling nozzle forms a predetermined angle with respect to the spray direction, which is not perpendicular to the spray direction.

11. 1. A wafer sampling retrieval and cleaning method using a wafer sampling retrieval and cleaning system, comprising: (a) receiving a wafer sampling solution via a collection section; (b) cleaning the blocking wall of the collection section through the cleaning section; (c) a step of discharging the sampling solution to the outside through the drain portion.

12. The step (b) includes: (b1) determining a direction of spray of a cleaning solution; (b2) determining a spray intensity of the cleaning solution; Following the step (b1) or the step (b2), 12. The wafer sampling recovery and cleaning method of claim 11, further comprising the step of: (b3) supplying a cleaning solution to the blocking wall.

13. The step (b1) (b11) providing at least one wall washing nozzle for supplying a washing solution to the blocking wall; When the predicted adhesion strength of the particles on the barrier wall is higher than a predetermined reference adhesion strength, (b12) adjusting the jet direction of the wall surface cleaning nozzle toward the blocking wall, When the predicted adhesion strength of the particles on the barrier wall is lower than or equal to a predetermined reference adhesion strength, (b13) The wafer sampling recovery and cleaning method according to claim 12, further comprising a step of adjusting the jetting direction of the wall surface cleaning nozzle toward the wafer side.

14. The step (b2) (b21) fastening the second housing to the top of the first housing; (b22) injecting a cleaning solution into a cleaning solution storage section and supplying the cleaning solution to the blocking wall; If the sampling solution in the barrier remains at or above the reference value, (b23) The wafer sampling, recovery and cleaning method according to claim 12, further comprising the step of adjusting the height of the second housing downward by a height adjusting unit.

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