Cleaning jig and cleaning method

Abstract

To provide a cleaning fixture for effectively cleaning a chuck table with high strength in a short time and a low cost and a cleaning method.SOLUTION: A cleaning fixture 1 for cleaning a chuck table 2 containing: a porous member 4 of which an upper surface is flatness; and a frame body that houses the porous member 4 while being exposed to an upper direction, includes: a main body 3 in which a fluid supply path 5 reached to an exhaust nozzle 5b formed on a back side from an inlet port formed on a front side; and a surface which is opposite to the upper surface of the porous member 4 on the back side of the main body 3. In the circumference of the exhaust nozzle 5b on the back side of the main body 3, a groove is formed. In the main body 3, a fluid exhaust path 7 communicated with the groove is formed. Also, a cleaning method for cleaning the chuck table 2, includes steps of: distributing the cleaning fixture 1 having the exhaust nozzle so that the exhaust nozzle 5b is faced to the porous member 4; exhausting the fluid with high pressure from the exhaust nozzle 5b; and cleaning the chuck table 2 so that the fluid with the high pressure is reached to a bottom part of the porous member 4 via the porous member 4.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a cleaning jig used for cleaning a chuck table provided with a porous member installed in a processing apparatus for processing a workpiece such as a semiconductor wafer, and a cleaning method for cleaning the chuck table.

Background Art

[0002] In the manufacturing process of device chips used in electronic devices such as mobile phones and computers, first, a plurality of devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integrations) are formed on the surface of a semiconductor wafer. Next, the wafer is ground from the back side to be thinned to a predetermined thickness, the back side is polished to be flattened, and the wafer is divided into individual device chips for each device.

[0003] Processing apparatuses such as a grinding apparatus for grinding a workpiece such as a wafer, a polishing apparatus for polishing, and a dicing apparatus for dicing include a chuck table for holding the workpiece and a processing unit for processing the workpiece held on the chuck table. The chuck table includes, for example, a flat porous member having the same planar shape as the workpiece, and a frame for accommodating the porous member while exposing it upward. A suction passage having one end connected to the porous member is formed inside the frame, and a suction source such as a suction pump is connected to the other end of the suction passage.

[0004] When processing a workpiece with a processing apparatus, a processing liquid such as pure water is supplied to the workpiece and the processing unit, and the processing chips generated during processing are taken into the processing liquid and removed. However, when the processing apparatus successively processes workpieces, the processing liquid containing the processing chips adheres to the chuck table. Therefore, conventionally, the processing chips have been removed from the surface of the chuck table by bringing a cleaning tool such as a brush into contact with the rotating chuck table while rotating the cleaning tool by a motor.

[0005] However, processing debris can sometimes get trapped in the porous material of the chuck table. In addition, during the manufacturing process of the chuck table, the top surface on which the workpiece is placed is ground to a predetermined shape, and the processing debris generated in this process also gets trapped in the porous material.

[0006] Processing debris that gets trapped in porous materials cannot be easily removed with a brush. If processing debris gets trapped in the porous material, the suction passage can become blocked, which may result in insufficient suction of the workpiece by the chuck table. In addition, when removing the workpiece from the chuck table after processing, the suction passage of the chuck table is reversed to expel water or air from the porous material, but this may cause some of the processing debris trapped in the porous material to be ejected and adhere to the workpiece.

[0007] Furthermore, when placing the next workpiece to be processed onto the chuck table, processing debris ejected from the top surface of the porous material can become trapped between the workpiece and the chuck table, creating a gap between them. If the workpiece is processed in this state, processing water can seep in through the gap, further contaminating the chuck table. Moreover, when the supply of processing water is temporarily stopped, the inflow of grinding water stops and only air is sucked in, causing a large change in the suction pressure of the chuck table, which can lead to the processing device detecting a suction pressure error.

[0008] Therefore, a cleaning device was developed that sprays a mixed fluid, a mixture of high-pressure air and liquid, onto the upper surface of the chuck table in order to remove machining debris that has entered the chuck table (see Patent Document 1). [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2011-200785 [Overview of the project] [Problems that the invention aims to solve]

[0010] However, simply spraying a mixed fluid consisting of high-pressure air and liquid onto the chuck table resulted in the fluid losing momentum upon impact with the top of the porous material, making it impossible to completely remove processing debris that had penetrated into the interior of the porous material or below it. In other words, the area of ​​action of the mixed fluid was small. Furthermore, it was necessary to incorporate the configuration for spraying the mixed fluid into the processing equipment, which was costly.

[0011] Therefore, a cleaning method was implemented in which water was backflowed into the suction passage of the chuck table to expel water from the porous material, and then the suction passage was sucked up. This process was repeated for about 50 hours, followed by cleaning with a brush for 5 days. However, even with this method and the time spent, it was not possible to completely remove the debris that had entered the chuck table.

[0012] Therefore, the problem of frequent detection of suction pressure errors in the chuck table of the processing equipment was not sufficiently resolved. Furthermore, the problem of processing debris adhering to the workpiece after it was removed from the processing equipment was also not sufficiently improved.

[0013] This invention has been made in view of the above problems, and its objective is to provide a cleaning jig and a cleaning method that enable high-strength, effective, short-time, and low-cost cleaning of a chuck table. [Means for solving the problem]

[0014] According to one aspect of the present invention, a cleaning jig for cleaning a chuck table comprising a porous member having a flat upper surface and a frame that houses the porous member while exposing it upward, the jig having a body with a fluid supply passage formed therein from an inlet formed on the front side to an outlet formed on the back side, the back side of the body having a surface facing the upper surface of the porous member, a groove formed around the outlet on the back side of the body, and the body having a fluid discharge passage connected to the groove. When the back surface is brought into contact with the porous member and high-pressure fluid is ejected from the nozzle, some of the high-pressure fluid reaches the bottom of the porous member, while other parts of the fluid travel between the main body and the porous member to the groove and are discharged from the fluid discharge channel.A cleaning jig characterized by the above is provided. Preferably, when the back surface is facing the porous member, the body is closer to the porous member in the region outside the groove on the back side than in other regions. Also preferably, the nozzle and the groove are formed on the surface.

[0015] Furthermore, according to another aspect of the present invention, a cleaning jig is provided for cleaning a chuck table including a porous member having a flat upper surface and a frame that houses the porous member while exposing it upward, the cleaning jig having a main body having a fluid supply passage formed therein from an inlet formed on the front side to an outlet formed on the back side, the back side of the main body having a surface facing the upper surface of the porous member, a groove formed around the outlet on the back side of the main body, a fluid discharge passage formed in the main body that leads to the groove, and the main body being closer to the porous member in the region outside the groove on the back side than in other regions. According to yet another aspect of the present invention, a cleaning jig is provided for cleaning a chuck table including a porous member having a flat upper surface and a frame that houses the porous member while exposing it upward, the cleaning jig having a body having a fluid supply passage formed therein from an inlet formed on the front side to an outlet formed on the back side, the back side of the body having a surface facing the upper surface of the porous member, a groove formed around the outlet on the back side of the body, a fluid discharge passage formed in the body that leads to the groove, and the outlet and the groove being formed on the surface.

[0016] According to another aspect of the present invention, a cleaning method is provided for cleaning a chuck table including a porous member having a flat upper surface and a frame that houses the porous member while exposing it upward, the cleaning method comprising: an arrangement step of arranging a cleaning jig having a nozzle so that the nozzle faces the porous member of the chuck table; an ejection step of ejecting a high-pressure fluid from the nozzle; and a cleaning step of cleaning the chuck table by allowing the high-pressure fluid to reach the bottom of the porous member through the porous member.

[0017] Preferably, the fluid is either water and / or air.

[0018] In a more preferable cleaning step, the chuck table sucks the fluid while the high-pressure fluid is ejected from the nozzle. [Effects of the Invention]

[0019] In the cleaning process of a chuck table using a cleaning jig and cleaning method according to one aspect of the present invention, a high-pressure fluid is brought to the bottom of the porous member. When the high-pressure fluid reaches the bottom of the porous member, it is ejected from the lower surface of the porous member to the bottom of the receiving recess of the frame. As a result, the high-pressure fluid acts on the debris accumulated in the frame, and the debris is thoroughly removed. In addition, debris accumulated inside the porous member is also removed during the process in which the high-pressure fluid reaches the lower surface of the porous member.

[0020] Thus, in the cleaning process of a chuck table using the cleaning jig and cleaning method according to one aspect of the present invention, the chuck table can be cleaned effectively with high intensity. Furthermore, by applying high-pressure fluid to every corner of the chuck table, debris can be sufficiently removed in a short cleaning time, and the cost of cleaning is also reduced.

[0021] Therefore, according to one aspect of the present invention, there is provided a cleaning jig and a cleaning method that can achieve cleaning of a chuck table with high strength, effectiveness, and low cost in a short time.

Brief Description of the Drawings

[0022] [Figure 1] FIG. 1(A) is a perspective view schematically showing a chuck table, and FIG. 1(B) is a cross-sectional view schematically showing the chuck table. [Figure 2] FIG. 2(A) is a perspective view schematically showing the front side of the cleaning jig, and FIG. 2(B) is a perspective view schematically showing the back side of the cleaning jig. [Figure 3] FIG. 3(A) is a plan view schematically showing the back side of the cleaning jig, FIG. 3(B) is a cross-sectional view schematically showing a cross-section of the cleaning jig, and FIG. 3(C) is a cross-sectional view schematically showing another cross-section of the cleaning jig. [Figure 4] It is a perspective view schematically showing the arrangement step. [Figure 5] It is a cross-sectional view schematically showing a conventional cleaning method. [Figure 6] It is a cross-sectional view schematically showing the ejection step and the cleaning step. [Figure 7] It is a cross-sectional view schematically showing an enlarged bottom portion of the porous member and the frame. [Figure 8] It is a flowchart showing the flow of each step of the cleaning method of the chuck table according to the embodiment.

Embodiments for Carrying Out the Invention

[0023] Referring to the accompanying drawings, embodiments according to one aspect of the present invention will be described. The usage mode of the cleaning jig according to this embodiment and the chuck table to be cleaned by the cleaning method will be described. FIG. 1(A) is a perspective view schematically showing a chuck table 2.

[0024] The chuck table 2 is installed in a processing apparatus that processes workpieces such as semiconductor wafers. The chuck table 2 is used to hold the workpiece by suction. The processing apparatus processes the workpiece held by the chuck table 2.

[0025] The workpiece is, for example, a wafer made of silicon, SiC (silicon carbide), or other semiconductor material, or a roughly disc-shaped substrate made of sapphire, glass, quartz, or other material. The surface of the workpiece is divided into multiple regions by multiple division lines (streets) arranged in a grid pattern, and devices such as ICs and LSIs are formed in each of these regions. Finally, individual device chips are formed by dividing the workpiece along the division lines.

[0026] The workpiece is thinned by grinding its back surface. The ground back surface of the workpiece forms minute irregularities called grinding marks. If the workpiece is then divided along the planned division lines to manufacture device chips, these minute irregularities will remain on the device chips, reducing their flexural strength. Therefore, the back surface of the ground workpiece is polished to remove these minute irregularities and flatten the surface. This prevents these minute irregularities from remaining on the device chips.

[0027] The chuck table 2 is used in conjunction with processing equipment such as a splitting device for dividing a workpiece, a grinding device for grinding a workpiece, or a polishing device for polishing a workpiece. The various processing devices use the chuck table 2 to hold the workpiece by suction and then process the workpiece held by the chuck table 2.

[0028] Next, the chuck table 2 will be described. Figure 1(B) is a schematic cross-sectional view of the chuck table 2. The chuck table 2 includes a porous member 4 with a flat upper surface 4a, and a frame 6 that houses the porous member 4 while exposing it upwards. The porous member 4 is a porous plate-shaped member made of a material such as ceramics. The planar shape and size of the porous member 4 are appropriately designed to match the planar shape and size of the workpiece to be processed by the processing device. If the shape of the workpiece is disc-shaped, the porous member 4 will also be disc-shaped.

[0029] A receiving recess 6c capable of accommodating the porous member 4 is formed on the upper surface 6a side of the frame 6. A base metal member 12 that supports the porous member 4 is disposed at the bottom of the receiving recess 6c. The shape and size of the receiving recess 6c are roughly consistent with those of the porous member 4. The porous member 4 is fixed to the frame 6 while being housed in the receiving recess 6c of the frame 6 and supported by the base metal member 12. When the porous member 4 is housed in the frame 6, the upper surface 4a of the porous member 4 is exposed upwards. This upper surface 4a of the porous member 4 becomes the holding surface of the chuck table 2.

[0030] Inside the frame 6, a suction passage 8 is formed, connecting the lower surface 6b and the receiving recess 6c. Below the receiving recess 6c, the suction passage 8 branches into a number of branch passages 14, each branch passage 14 leading to various points on the bottom of the receiving recess 6c. The suction passage 8 and the branch passages 14 are surrounded by a base metal member 12.

[0031] A suction source 10a, installed in the processing equipment where the chuck table 2 is installed or in the factory where the processing equipment is installed, is connected to a suction passage 8 that leads to the lower surface 6b of the frame 6. The suction source 10a is composed of, for example, a vacuum pump or an ejector. When a workpiece is placed on the upper surface 4a of the porous member 4 and the suction source 10a is activated, the negative pressure generated by the suction source 10a acts on the workpiece through the suction passage 8, each branch passage 14, and the porous member 4. As a result, the workpiece is held in place by the chuck table 2.

[0032] Furthermore, a fluid supply source 10b provided in the processing equipment where the chuck table 2 is installed or in the factory where the processing equipment is installed may be connected to the suction passage 8 exposed on the lower surface 6b of the frame 6. After processing the workpiece held by the chuck table 2, the workpiece may stick to the chuck table 2, making it difficult to remove. In such cases, the fluid supply source 10b is activated to cause a fluid such as water to flow back through the suction passage 8, etc., and be ejected from the upper surface 4a of the porous member 4. This causes the workpiece to float up, making it easier to remove the workpiece from the chuck table 2.

[0033] Furthermore, the fluid supply source 10b may be used for purposes other than removing the workpiece from the chuck table 2. For example, activating the fluid supply source 10b when no workpiece is placed on it can expel some of the dust that has entered the porous member 4 to the upper surface 4a. However, with this method, it is difficult to discharge all dust and other debris to the outside of the porous member 4.

[0034] When the porous member 4 is housed in the receiving recess 6c to manufacture the chuck table 2, the porous member 4 is fixed to the base metal member 12 by adhesive 16. Then, the upper surface 4a of the porous member 4 and the upper surface 6a of the frame 6 are ground and flattened to a uniform height. At this time, processing chips are generated and enter the interior of the porous member 4.

[0035] Furthermore, when processing a workpiece with the processing device, a processing fluid such as pure water is supplied to the workpiece and the processing unit, and processing debris generated during processing is taken into the processing fluid and removed. However, as workpieces are processed one after another with the processing device, the processing fluid containing the processing debris adheres to the chuck table 2, and some of the processing debris enters the porous member 4.

[0036] Therefore, by cleaning the chuck table 2 using the cleaning jig and cleaning method according to one aspect of this embodiment, debris that has entered the inside of the chuck table 2 is removed. Next, the cleaning jig according to one aspect of this embodiment will be described.

[0037] Figure 2(A) is a schematic perspective view showing the front side 3a of the main body 3 of the cleaning jig 1, and Figure 2(B) is a schematic perspective view showing the back side 3b of the main body 3 of the cleaning jig 1. Figure 3(A) is a schematic plan view showing the back side 3b of the main body 3 of the cleaning jig 1, and Figures 3(B) and 3(C) are schematic cross-sectional views showing the cross section of the main body 3 of the cleaning jig 1. The cleaning jig 1 has a main body 3 in which a fluid supply passage 5 is formed, extending from an inlet 5a formed on the front side 3a to an outlet 5b formed on the back side 3b.

[0038] The main body 3 is formed from materials such as ABS (acrylonitrile, butadiene, styrene) resin, ASA (acrylate, styrene, acrylonitrile) resin, PP (polypropylene) resin, epoxy resin, or acrylic resin. However, the material of the main body 3 is not limited to these. The main body 3 is manufactured using a 3D printer or injection molding machine, or it may be manufactured by removing unwanted parts from a block made of resin material. However, the manufacturing method of the main body 3 is not limited to these.

[0039] The main body 3 has a fluid supply passage 5 formed therein, extending from an inlet 5a formed on the front side 3a to an outlet 5b formed on the back side 3b. The main body 3 has one or more fluid supply passages 5 and one or more inlets 5a and outlets 5b corresponding to each fluid supply passage 5. Each figure schematically shows the main body 3 with six fluid supply passages 5 as an example. However, the number of fluid supply passages 5 is not limited to this.

[0040] The number of fluid supply passages 5 should be determined, for example, to match the number of high-pressure fluid supply systems provided in the processing equipment, etc., on which the cleaning jig 1 is used. Each inlet 5a of the fluid supply passage 5 should be connected to a high-pressure fluid supply system by piping. To clean the chuck table 2 more effectively, it is desirable to connect as many supply systems as possible to the cleaning jig 1. Therefore, it is preferable that the cleaning jig 1 has fluid supply passages 5 in a number that corresponds to the number of supply systems to which high-pressure fluid can be connected.

[0041] Here, there are no particular restrictions on the arrangement of the multiple inlets 5a on the front side 3a of the main body 3, but it is desirable that they be arranged so that they are as close to each other as possible. However, when a pipe connected to a high-pressure fluid supply system is connected to one inlet 5a, it is necessary that the connection of other pipes to other inlets 5a is not obstructed. For this reason, adjacent inlets 5a must be separated by a distance greater than the distance required for connecting the pipes.

[0042] The main body 3 has a flat surface on its back side 3b. When the cleaning jig 1 is placed on the chuck table 2 for cleaning, this flat surface on the back side 3b of the main body 3 faces the upper surface 4a of the porous member 4. The same number of nozzles 5b as there are fluid supply passages 5 are formed on the back side 3b of the main body 3. When the fluid supply passages 5 are formed along the shortest distance from the front side 3a to the back side 3b, the arrangement of the nozzles 5b on the back side 3b is the inverse arrangement of the inlet 5a on the front side 3a. However, the arrangement of the nozzles 5b is not limited to this.

[0043] Furthermore, the fluid supply passage 5 that penetrates the main body 3 does not have to be straight, and may be curved between the inlet 5a and the outlet 5b. In other words, the arrangement of the outlet 5b does not have to correspond to the arrangement of the inlet 5a, and may be determined independently of the arrangement of the inlet 5a.

[0044] A groove 9 is formed around the nozzle 5b on the back side 3b of the main body 3. For example, the groove 9 is formed along the outer circumference of the back side 3b of the main body 3, surrounding the nozzle 5b on the back side 3b of the main body 3. Here, on the back side 3b of the main body 3, each nozzle 5b does not come into contact with the groove 9. There are no restrictions on the width and depth of the groove 9, and they are determined as appropriate as long as the groove 9 can perform the functions described later.

[0045] The main body 3 has a fluid discharge passage 7 that connects to a groove 9. One end of the fluid discharge passage 7 connects to the groove 9, and the other end connects to the front side 3a of the main body 3. There is no particular limit to the number of fluid discharge passages 7 formed in the main body 3.

[0046] For example, if the main body 3 is box-shaped or rectangular, the back side 3b of the main body 3 will be approximately rectangular. In this case, the groove 9 will be formed in a rectangular shape along the outer circumference of the back side 3b. The fluid discharge passage 7 will be formed at the corner of the groove 9. However, the shape of the groove 9 and the position of the fluid discharge passage 7 are not limited to these.

[0047] When the cleaning jig 1 is used in a processing device or the like, a pipe 26 is connected to the inlet 5a of the fluid supply passage 5, as shown in Figure 4. On the other hand, nothing is connected to the fluid discharge passage 7 on the front side 3a of the main body 3, and the fluid discharge passage 7 is open to the atmosphere. However, a suction source (not shown) may be connected to the fluid discharge passage 7.

[0048] Next, the cleaning method according to this embodiment will be described. The cleaning method according to this embodiment is a method for cleaning the chuck table 2 to remove debris, and is carried out using, for example, the cleaning jig 1 shown in each figure. That is, the following description is a description of how to use the cleaning jig 1 according to this embodiment.

[0049] Figure 8 is a flowchart illustrating the flow of each step in the cleaning method according to this embodiment. In the cleaning method according to this embodiment, first, a setup step S10 is performed in which a cleaning jig 1 having a nozzle 5b is positioned so that the nozzle 5b faces the porous member 4 of the chuck table 2. Figure 4 is a schematic perspective view showing the setup step S10.

[0050] When the installation step S10 is carried out, the pipes 26 are connected to each inlet 5a in advance, as shown in Figure 4. A high-pressure fluid supply system (not shown) capable of supplying either water and / or air at high pressure is connected to one end of the pipes 26. Preferably, the high-pressure fluid supply system can supply high-pressure water as the cleaning fluid.

[0051] In the placement step S10, the cleaning jig 1 is placed on the porous member 4 with the flat surface 3b on the back of the main body 3 of the cleaning jig 1 facing the upper surface 4a of the porous member 4. For example, the worker holds the cleaning jig 1 by hand and positions it on the porous member 4. At this time, the cleaning jig 1 may be in contact with the porous member 4, or it may be slightly lifted above the porous member 4.

[0052] Next, ejection step S20 is performed, in which high-pressure fluid is ejected from the nozzle 5b. That is, the high-pressure fluid supply system is activated, and high-pressure fluid is supplied to the inlet 5a of the fluid supply passage 5 through the piping 26. The high-pressure fluid then travels through the fluid supply passage 5, reaches the nozzle 5b, and is ejected from the nozzle 5b downwards towards the main body 3.

[0053] In the cleaning method according to this embodiment, the placement step S10 may be performed after the ejection step S20. In this case, the cleaning jig 1, which ejects high-pressure fluid from the nozzle 5b, is placed on the porous member 4 of the chuck table 2. At this time, the high-pressure fluid collides with the porous member 4 and scatters into the surroundings, so it is preferable that the ejection step S20 is performed after the placement step S10.

[0054] Here, the pressure of the high-pressure fluid ejected from the nozzle 5b is higher than atmospheric pressure. The pressure of the high-pressure fluid is preferably between 2 atmospheres and 5 atmospheres. When a high-pressure fluid supply system is provided in a processing device or the like for a predetermined purpose, the fluid regulated for that purpose may be supplied directly to the cleaning jig 1. Preferably, the pressure of the fluid supplied to the cleaning jig 1 and ejected from the nozzle 5b is about 3 atmospheres. However, the fluid pressure is not limited to this.

[0055] Furthermore, the flow rate of the fluid ejected from the nozzle 5b is preferably, for example, 10 L / min or more and 30 L / min or less. When a high-pressure fluid supply system is provided in the processing equipment for a predetermined purpose, it is preferable that the fluid be supplied at the maximum flow rate that can be supplied from this supply system. The larger the amount of fluid ejected from the nozzle 5b, the more effectively the chuck table 2 can be cleaned. Preferably, the flow rate of the high-pressure fluid is about 20 L / min.

[0056] When the placement step S10 and the ejection step S20 are performed, the high-pressure fluid ejected from the nozzle 5b enters the porous member 4, and the chuck table 2 is cleaned. Next, the cleaning step S30, in which the high-pressure fluid reaches the bottom of the porous member 4 through the porous member 4 to clean the chuck table 2, will be described.

[0057] First, for comparison, let's describe an example of conventional cleaning of the chuck table 2. Figure 5 is a schematic cross-sectional view showing the conventional cleaning of the chuck table 2. Conventionally, for example, a spray nozzle 18 was positioned above the porous member 4 of the chuck table 2, and a high-pressure mixed fluid 20, a mixture of water and air, was sprayed from the spray nozzle 18 toward the upper surface 4a of the porous member 4 to clean the chuck table 2.

[0058] The mixed fluid 20 ejected from the injection nozzle 18 travels through the atmosphere and collides with the upper surface 4a of the porous member 4. At this time, the porous member 4 receives a strong impact, but some of the mixed fluid 20 does not enter the porous member 4 and is scattered into the surroundings. Figure 5 schematically shows the scattered fluid 22. In addition, some of the mixed fluid 20 that enters the porous member 4 rapidly loses its momentum and becomes simple water at atmospheric pressure.

[0059] Therefore, the area in which the high-pressure mixed fluid 20 acts in that state is limited to an extremely narrow area near the upper surface 4a of the porous member 4. In Figure 5, the region 24a in which the high-pressure mixed fluid 20 effectively cleans the porous member 4 is schematically shown by diagonal lines. Areas away from the upper surface 4a of the porous member 4 are not effectively cleaned, and debris and other contaminants tend to remain there.

[0060] Furthermore, in the conventional method, only water at atmospheric pressure flowed down from the lower surface 4b of the porous member 4. As a result, the high-pressure mixed fluid 20 could not reach the base metal member 12, suction passage 8, and support passage 14 shown in Figure 1, which are located at the bottom of the housing recess 6c of the frame 6 of the chuck table 2, and these were not sufficiently cleaned.

[0061] Even when the suction source 10a connected to the suction passage 8 was activated during cleaning the chuck table 2, negative pressure leaked outside the area where the mixed fluid 20 sprayed from the spray nozzle 18 of the porous member 4 collided. As a result, the negative pressure generated by the suction source 10a did not restore effective cleaning power to the water that had lost momentum.

[0062] In particular, debris tended to accumulate around the adhesive 16 used to bond the base metal member 12 and the porous member 4, and this debris was difficult to remove. Furthermore, when the workpiece was removed from the chuck table 2, and the fluid supply source 10b was activated to spray a fluid such as water from the upper surface 4a of the porous member 4, some of the debris that had accumulated around the adhesive 16 and on the porous member 4 was taken up by the fluid. As a result, when the fluid was sprayed from the upper surface 4a of the porous member 4, debris adhered to the workpiece.

[0063] In contrast, in the cleaning step S30 of the cleaning method according to this embodiment, a high-pressure fluid is brought to the bottom of the porous member 4, and the high-pressure fluid is ejected from the lower surface 4b of the porous member 4 to the bottom of the housing recess 6c of the frame 6. Figure 6 is a schematic cross-sectional view showing the cleaning step S30. Next, the cleaning step S30 in the cleaning method according to this embodiment will be described in detail.

[0064] In cleaning step S30, the high-pressure fluid 20a ejected from the nozzle 5b of the cleaning jig 1 is supplied to the small gap between the main body 3 of the cleaning jig 1 and the upper surface 4a of the porous member 4. A portion of the high-pressure fluid 20a then travels along the upper surface 4a of the porous member 4 away from the nozzle 5b, while another portion of the high-pressure fluid 20a advances into the interior of the porous member 4. At this time, the high-pressure fluid 20a is held down by the main body 3 of the cleaning jig 1 and does not come into contact with the atmosphere, so a pressure drop is unlikely to occur.

[0065] Therefore, the high-pressure fluid 20a advancing towards the porous member 4 proceeds toward the lower surface 4b while maintaining roughly the same pressure. During this process, the high-pressure fluid 20a acts on debris and other materials contained in the porous member 4, removing them. In Figure 6, the region 24b where the high-pressure fluid 20a effectively cleans the porous member 4 is schematically shown by diagonal lines. Then, while maintaining an effective pressure, the high-pressure fluid 20a reaches the lower surface 4b of the porous member 4.

[0066] From another perspective, the cleaning jig 1 uses its main body 3 to suppress the pressure drop of the high-pressure fluid 20a. The countless pores contained in the porous member 4 then function as a transmission path for the high-pressure fluid 20a, transmitting it to the lower surface 4b. As a result, the high-pressure fluid 20a is ejected downwards from the lower surface 4b of the porous member 4.

[0067] However, the pressure of the high-pressure fluid 20a reaching the bottom of the porous member 4 does not need to be exactly the same as the pressure at which it was ejected from the nozzle 5b. If the pressure of the high-pressure fluid 20a reaching the bottom of the porous member 4 exceeds atmospheric pressure, the chuck table 2 can be cleaned more effectively than with conventional methods. Of course, the less pressure loss there is in the high-pressure fluid 20a, the more effectively the chuck table 2 will be cleaned.

[0068] In this manner, when the back side 3b of the main body 3 is facing the porous member 4 and high-pressure fluid 20a is ejected from the nozzle 5b, some of the high-pressure fluid 20a reaches the bottom of the porous member 4. On the other hand, the remaining portion of the high-pressure fluid 20a that was ejected from the nozzle 5b but did not enter the porous member 4 travels between the surface of the back side 3b of the main body 3 and the top surface 4a of the porous member 4 and reaches the groove 9. From there, it travels through the groove 9 to the fluid discharge passage 7 and is discharged from the fluid discharge passage 7 to the front side 3a of the main body 3.

[0069] Furthermore, any remaining portion of the high-pressure fluid 20a that did not enter the porous member 4 continues to travel along the upper surface 4a of the porous member 4 without entering the groove 9, and is ejected out through the gap between the main body 3 and the porous member 4.

[0070] Figure 6 schematically shows the high-pressure fluids 28 and 30 ejected to the outside of the main body 3. At this point, the high-pressure fluids 28 and 30 come into contact with the atmosphere for the first time, and their pressure rapidly decreases. The high-pressure fluid 20a that did not enter the porous member 4 maintains an appropriate distance between the main body 3 and the porous member 4. Therefore, the main body 3 does not come into contact with the porous member 4 and is not worn down, and there is no generation of debris due to wear of the main body 3.

[0071] For example, if all of the high-pressure fluid 20a ejected from the nozzle 5b is to enter the porous member 4, the repulsive force associated with the ejection of the high-pressure fluid 20a from the nozzle 5b becomes large, causing the main body 3 to lift significantly and become unstable. In this case, the main body 3 and the porous member 4 are separated by a large distance, and the pressure of the high-pressure fluid 20a advancing into the porous member 4 tends to decrease. On the other hand, if not all of the high-pressure fluid 20a enters the porous member 4, and some of the high-pressure fluid 20a escapes appropriately, the gap between the main body 3 and the porous member 4 is maintained appropriately.

[0072] If grooves 9 and fluid discharge channels 7 are not formed in the main body 3 of the cleaning jig 1, fluid 28 will be ejected into the atmosphere with extremely strong force from the gap between the main body 3 and the porous member 4. This will cause fluid to splatter around the chuck table 2, contaminating the surrounding area, and will also spray onto the worker, reducing work efficiency. In contrast, if grooves 9 and fluid discharge channels 7 are formed in the main body 3 of the cleaning jig 1, a moderately high-pressure fluid 20a is discharged from the fluid discharge channels 7, thereby suppressing the force with which fluid splatters outward from the gap between the main body 3 and the porous member 4.

[0073] Figure 7 schematically shows the high-pressure fluid 20a ejected downward from the lower surface 4b of the porous member 4 at the bottom of the receiving recess 6c of the frame 6. The high-pressure fluid 20a ejected downward from the lower surface 4b powerfully removes the debris 32 that accumulates below the porous member 4.

[0074] In particular, debris 32 tended to accumulate around the adhesive 16, which was one of the causes of various problems. In the cleaning step S30, high-pressure fluid 20a acts on this debris 32, washing it away, and the high-pressure fluid 20a containing the debris 32 is sucked to the suction source 10a through the support passage 14 and the suction passage 8. As a result, the chuck table 2 is cleaned very powerfully.

[0075] In cleaning step S30, the operator holds the cleaning jig 1 by hand and moves it over the upper surface 4a of the porous member 4. At this time, the body 3 of the cleaning jig 1 is slightly lifted by the ejection of high-pressure fluid 20a from the nozzle 5b, so that the cleaning jig 1 moves smoothly without contacting the upper surface 4a of the porous member 4. In other words, the movement of the cleaning jig 1 is smooth, and the problem of the body 3 coming into contact with the porous member 4 and being scraped, thus generating debris, is avoided.

[0076] The operator repeatedly moves the cleaning jig 1 over the entire upper surface 4a of the porous member 4. This supplies high-pressure fluid 20a to various parts of the porous member 4, cleaning various parts of the chuck table 2. Cleaning the chuck table 2 using the cleaning jig 1 allows for extremely quick and easy cleaning of the chuck table 2.

[0077] Conventionally, a cleaning method was used in which, for example, water was backflowed into the suction passage 8 of the chuck table 2 to eject water from the upper surface 4a of the porous member 4, and then the suction passage 8 was sucked up. This process was repeated for about 50 hours, and then the chuck table 2 was cleaned using a brush for 5 days. However, even with this method and for this amount of time, it was not possible to completely remove the debris that had entered the chuck table 2.

[0078] In contrast, with the cleaning method using the cleaning jig 1, the debris that had entered the chuck table 2 could be almost completely removed by simply performing the cleaning step S30 for about 10 minutes while moving the cleaning jig 1. As a result, the frequency of suction pressure errors in the chuck table 2 caused by debris was drastically reduced in the processing apparatus. Furthermore, the amount of debris adhering to the workpiece when the suction passage 8 was reversed and water was ejected from the upper surface 4a of the porous member 4 after processing the workpiece held by the chuck table 2 was also drastically reduced.

[0079] As described above, the cleaning jig 1 and cleaning method according to this embodiment allow for effective and high-intensity cleaning of the chuck table 2. As a result, virtually no debris remains on the chuck table 2, and problems caused by debris residue can be suppressed. Furthermore, the time required to clean the chuck table 2 is significantly reduced, and the amount of high-pressure fluid 20a used for cleaning is also reduced by the amount of time saved, resulting in extremely low cleaning costs.

[0080] Here, although the cleaning jig 1 has a completely different cleaning effect and mechanism of action, it cleans the chuck table 2 by moving along the upper surface 4a of the porous member 4, similar to brushes conventionally used for cleaning the chuck table 2. Therefore, it is also possible to name the cleaning jig 1 a water brush. However, the configuration and usage of the cleaning jig 1 are not limited by this name.

[0081] It should be noted that the present invention is not limited to the embodiments described above and can be implemented with various modifications. For example, in the above embodiments, the case in which the high-pressure fluid 20a supplied to the cleaning jig 1 through the piping 26 and ejected from the nozzle 5b is water was described as an example, but one aspect of the present invention is not limited to this.

[0082] The high-pressure fluid 20a may be air. Alternatively, it may be a mixed fluid of water and air. When air is included in the high-pressure fluid 20a, the pressure of the high-pressure fluid 20a can be increased. On the other hand, when air is not included in the high-pressure fluid 20a, the pressure of the high-pressure fluid 20a does not decrease as it moves through the porous member 4.

[0083] Furthermore, the above embodiments described a case in which a high-pressure fluid 20a is supplied to the cleaning jig 1 through piping 26 from a supply system used for other purposes in the processing apparatus or factory equipment. The embodiments also described a case in which the cleaning of the chuck table 2 using the cleaning jig 1 is mainly performed manually by workers. However, the present invention is not limited to these embodiments.

[0084] In other words, the processing apparatus may be equipped with a dedicated cleaning mechanism, including a cleaning jig 1 and a dedicated supply system, so that the chuck table 2 can be cleaned immediately at any time. This cleaning mechanism may also include a moving mechanism for moving the cleaning jig 1 on the upper surface 4a of the porous member 4, and the processing apparatus may automatically clean the chuck table 2 using this cleaning mechanism.

[0085] In this case, there is no need to manually switch the fluid supply system connections, nor is there any need for workers to open the processing chamber of the processing equipment. As a result, the cleaning of the chuck table 2 can be performed with less effort and in a shorter time, contaminants from the outside do not enter the processing chamber, and scraps and the fluid used for cleaning do not diffuse from the processing chamber to the outside.

[0086] In the above embodiment, a case was described in which six fluid supply passages 5 are formed in the main body 3 of the cleaning jig 1 and six pipes 26 are connected to the cleaning jig 1. However, the present invention is not limited to this. For example, the cleaning jig 1 may have one fluid supply passage 5 and one pipe 26 connected to it. Even in this case, as long as the main body 3 covers the area around the nozzle 5b on the back side 3b of the main body 3, the high-pressure fluid 20a can be advanced to the bottom of the porous member 4.

[0087] Furthermore, although the above embodiment describes a case where the back side 3b of the main body 3 of the cleaning jig 1 is a flat surface, the present invention is not limited to this. That is, the back side 3b of the main body 3 does not have to be strictly flat, and the main body 3 may have an uneven shape on the back side 3b. For example, when the cleaning jig is placed on the upper surface 4a of the porous member 4, if the main body 3 is closer to the porous member 4 in the region outside the groove 9 on the back side 3b than in other regions, the high-pressure fluid 20a will be less likely to come into contact with the atmosphere, and a pressure drop can be suppressed.

[0088] Furthermore, the cleaning of the chuck table 2 may be performed while the chuck table 2 is mounted on the processing device. Alternatively, the cleaning of the chuck table 2 may be performed outside the processing device after it has been removed from the processing device.

[0089] Furthermore, the structures, methods, etc., according to the above embodiments can be modified as appropriate without departing from the scope of the objectives of the present invention. [Explanation of Symbols]

[0090] 1. Cleaning jig 3 Main unit 3a Front side 3b Reverse side 5 Fluid supply path 5a Inlet 5b spout 7 Fluid drain path 9 grooves 2 Chuck Table 4. Porous material 4a,6a Top surface 4b, 6b below 6. Frame 6c Containment recess 8 Attraction Path 10a Attractor 10b Fluid supply source 12 Taijin parts and materials 14 branch roads 16. Attaching material 18 jet ノズル 20 Mixed fluids 20a,22,28,30 Fluid 24a, 24b domains 26 Piping 32 pieces

Claims

1. A cleaning jig for cleaning a chuck table, comprising a porous member with a flat top surface and a frame that houses the porous member while exposing it upwards, The main body has a fluid supply channel formed therein, from an inlet formed on the front side to an outlet formed on the back side. The back side of the main body has a surface that faces the upper surface of the porous member, A groove is formed around the nozzle on the back side of the main body. The main body has a fluid discharge passage that leads to the groove, A cleaning jig characterized in that, when the back surface is brought into contact with the porous member and high-pressure fluid is ejected from the nozzle, some of the high-pressure fluid reaches the bottom of the porous member, while other parts of the fluid travel between the main body and the porous member to the groove and are discharged from the fluid discharge passage.

2. The cleaning jig according to Claim 1, characterized in that when the back surface is brought into contact with the porous member, the main body is closer to the porous member in the region outside the groove on the back side than in other regions.

3. The cleaning jig according to either Claim 1 or Claim 2, characterized in that the nozzle and the groove are formed on the surface.

4. A cleaning jig for cleaning a chuck table, comprising a porous member having a flat upper surface and a frame that houses the porous member while exposing it upward, The main body has a fluid supply channel formed from an inlet formed on the front side to an outlet formed on the back side, The back side of the main body has a surface that faces the upper surface of the porous member, A groove is formed around the nozzle on the back side of the main body. The main body has a fluid discharge passage that leads to the groove, The cleaning jig is characterized in that the main body is closer to the porous member in the area outside the groove on the back side than in other areas.

5. A cleaning jig for cleaning a chuck table, comprising a porous member having a flat upper surface and a frame that houses the porous member while exposing it upward, The main body has a fluid supply channel formed from an inlet formed on the front side to an outlet formed on the back side, The back side of the main body has a surface that faces the upper surface of the porous member, A groove is formed around the nozzle on the back side of the main body. The main body has a fluid discharge passage that leads to the groove, A cleaning jig characterized in that the nozzle and groove are formed on the surface.

6. A cleaning method for cleaning a chuck table, which includes a porous member having a flat upper surface and a frame that houses the porous member while exposing it upwards, A setup step involves arranging a cleaning jig having a nozzle so that the nozzle faces the porous member of the chuck table, A ejection step in which a high-pressure fluid is ejected from the nozzle, A cleaning method characterized by comprising a cleaning step of cleaning the chuck table by allowing a high-pressure fluid to reach the bottom of the porous member through the porous member.

7. The cleaning method according to claim 6, characterized in that the fluid is either water or air, or both.

8. The cleaning method according to claim 6 or 7, characterized in that, in the cleaning step, the chuck table sucks up the fluid while spraying the fluid at high pressure from the nozzle.

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