KR20100060656A - Substrate polishing apparatus and method of polishing substrate using the same - Google Patents

Abstract

PURPOSE: A substrate polishing device and a substrate polishing method using the same are provided to improve the reliability of products by fixing and installing a polishing end point detector on the upper side of a substrate support member aside from a polishing unit. CONSTITUTION: A substrate support member(100) receives a substrate on the upper side thereof and rotates the substrate. A polishing unit(300) polishes the substrate received on the substrate support member. A polishing end point detector(400) is fixed to the upper side of the substrate support member and detects the polishing end point of the substrate received in the substrate support member.

Description

Substrate polishing apparatus and substrate polishing method using same {SUBSTRATE POLISHING APPARATUS AND METHOD OF POLISHING SUBSTRATE USING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus and method, and more particularly, to a substrate processing apparatus and a method for polishing and cleaning a semiconductor substrate by a sheet-fed treatment method.

In general, a semiconductor device manufacturing process must repeatedly perform a plurality of unit processes such as a deposition process, a photo process, and an etching process to form and stack thin films. These processes are repeated until the desired circuit pattern is formed on the wafer, and after the circuit pattern is formed, a lot of bending occurs on the surface of the wafer. In recent years, as semiconductor devices become highly integrated, their structures are multilayered, and the number of bends on the surface of the wafer and the step between them are increasing. Unplanarization of the wafer surface causes problems such as defocus in the photolithography process, and thus the wafer surface must be polished periodically to planarize the surface of the wafer.

Various surface planarization techniques are used to planarize the surface of the wafer, but chemical mechanical polishing (CMP) apparatuses, which can obtain excellent flatness not only for narrow areas but also for wide areas, are mainly used. The chemical mechanical polishing apparatus is an apparatus for polishing a surface of a wafer coated with tungsten, an oxide, or the like by mechanical friction and polishing with a chemical abrasive, and enables very fine polishing.

In addition, as semiconductor devices become more dense, highly integrated, and higher in performance, miniaturization of circuit patterns proceeds rapidly, and contaminants such as particles, organic contaminants, and metal contaminants remaining on the substrate surface have a great effect on device characteristics and production yield. Get mad. For this reason, a cleaning process for removing various contaminants adhering to the substrate surface is very important in the semiconductor manufacturing process, and the substrate cleaning process is performed at the front and rear stages of each unit process for semiconductor manufacturing.

It is an object of the present invention to provide a substrate polishing apparatus capable of improving the reliability of a product.

It is also an object of the present invention to provide a method for polishing a substrate using the substrate polishing apparatus described above.

A substrate polishing apparatus according to one feature for realizing the above object of the present invention comprises a substrate supporting member, a polishing unit, and a polishing endpoint detection section.

The substrate support member is mounted on the substrate, and rotates the substrate. The polishing unit polishes the substrate seated on the substrate support member. The polishing endpoint detection unit is fixedly installed on the substrate support member, and detects an polishing endpoint of the substrate seated on the substrate support member.

In addition, the substrate polishing method according to one feature for realizing the above object of the present invention is as follows. First, the substrate is mounted on the substrate support member. The polishing pad of the polishing unit is disposed on the upper surface of the substrate. The substrate support member and the polishing pad are rotated to polish the upper surface of the substrate. The substrate having been polished is cleaned. In at least one of polishing the substrate and cleaning the substrate, the polishing endpoint of the substrate is detected using a polishing endpoint detection unit fixed to an upper portion of the substrate support member.

According to the present invention described above, since the polishing endpoint detection unit is fixedly installed on the substrate support member separately from the polishing unit, the thickness of the substrate can be accurately measured after the polishing process or after the cleaning process, and the reliability of the product can be improved. .

In addition, maintenance of the polishing endpoint detection unit is easy, and the thickness of the substrate can be measured even after the cleaning process.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Hereinafter, the wafer will be described as an example of a semiconductor substrate, but the spirit and scope of the present invention are not limited thereto.

1 is a view schematically showing a sheet type polishing system according to an embodiment of the present invention, and FIG. 2 is a side view illustrating the sheet type polishing system shown in FIG. 1.

1 and 2, the substrate processing system 2000 of the present invention includes a loading / unloading unit 10, an index robot 20, a buffer unit 30, and a main transfer robot. Robot) 50, a plurality of substrate polishing units 1000, and a controller 60.

The loading / unloading unit 10 includes a plurality of load ports 11a, 11b, 11c, and 11d. In this embodiment, the loading / unloading section 11 has four load ports 11a, 11b, 11c, 11d, but the number of load ports 11a, 11b, 11c, 11d is the substrate. It may be increased or decreased depending on the process efficiency and the foot print condition of the processing system 2000.

Front open unified pods (FOUPs) 12a, 12b, 12c, and 12d in which wafers are accommodated are mounted in the load ports 11a, 11b, 11c, and 11d. Each fulcrum 12a, 12b, 12c, 12d is formed with a plurality of slots for accommodating the wafers in a state in which they are arranged horizontally with respect to the ground. The wafers 12a, 12b, 12c, and 12d store wafers processed in each substrate polishing unit 1000 or wafers to be injected into the substrate polishing unit 1000. Hereinafter, for convenience of description, the wafers processed by the substrate polishing units 1000 are called processed wafers, and the wafers not yet processed are called raw wafers.

A first transfer passage 41 is formed between the loading / unloading portion 11 and the buffer portion 30, and a first transfer rail 42 is installed in the first transfer passage 41. The index robot 20 is installed on the first transfer rail 42 and moves wafers between the loading / unloading part 11 and the buffer part 30 while moving along the first transfer rail 42. Transfer. That is, the index robot 20 extracts at least one raw wafer from the unpacks 12a, 12b, 12c, and 12d mounted on the loading / unloading unit 11 and loads the raw wafers into the buffer unit 30. . In addition, the index robot 20 extracts at least one processed wafer from the buffer unit 30 and loads the processed wafers into the pools 12a, 12b, 12c, and 12d seated on the loading / unloading unit 11. .

On the other hand, the buffer unit 30 is installed on one side of the first transfer passage 41. The buffer unit 30 accommodates the raw wafers transferred by the index robot 20 and the processed wafers processed by the substrate polishing units.

The main transfer robot 50 is installed in the second transfer passage 43. The second transfer passage 43 is provided with a second transfer rail 44, and the second transfer rail 44 is provided with the main transfer robot 50. The main transfer robot 50 moves along the second transfer rail 44 to transfer wafers between the buffer unit 30 and the substrate polishing units. That is, the main transfer robot 50 pulls out at least one raw wafer from the buffer unit 30 to provide it to the substrate polishing unit 1000, and the wafer processed by the substrate polishing unit 1000, namely, The processed wafer is loaded into the buffer part 30.

The substrate polishing units are disposed at both sides of the second transfer passage 43, and each substrate polishing unit 1000 polishes and cleans the raw wafer to form the processed wafer. The substrate polishing units are disposed such that at least two substrate polishing units face each other with the second transfer passage 43 therebetween. In one example of the present invention, two substrate grinding portions are disposed in parallel along the second transfer passage 43, respectively, on both sides of the second transfer passage 43 in plan view, The number of substrate polishing units disposed on both sides may increase or decrease depending on the process efficiency and footprint of the substrate polishing system 2000.

In addition, the substrate polishing units may be arranged in multiple layers. In one example of the present invention, the substrate polishing units are stacked in two layers, two in one layer.

That is, the substrate polishing units are composed of eight substrate polishing units, and four substrate polishing units disposed in two layers, two in one layer, are disposed on both sides of the second transfer passage 43, respectively. The number of layers in which the substrate polishing units are stacked, the number of substrate polishing units disposed in each layer, and the number of rows in which the substrate polishing units are continuously arranged in parallel are increased according to the process efficiency and footprint of the substrate polishing system 1000. Or decrease. When the number of rows in which the substrate polishing units are arranged in parallel increases, the number of the second transfer passage 43 and the main transfer robot 50 also increases. In addition, when the number of layers on which the substrate polishing units are stacked increases, the number of the main transfer robots 50 may also increase.

As such, since the substrate polishing portions are disposed in a plurality of layers and a plurality of rows, the substrate polishing system 2000 may simultaneously polish and clean a plurality of wafers. Accordingly, the substrate polishing system 2000 may improve process efficiency and productivity and reduce footprint.

Meanwhile, each substrate polishing unit 1000 is connected to the controller 60, and polishes and cleans the raw wafer under the control of the controller 60. That is, the controller 60 controls the substrate polishing unit 1000 to locally adjust the polishing amount of the raw wafer by the substrate polishing unit 1000 to improve the polishing uniformity of the substrate polishing unit 1000.

Hereinafter, the structure of the substrate polishing unit 1000 will be described in detail with reference to the accompanying drawings.

3 is a perspective view illustrating the substrate polishing apparatus shown in FIG. 1, and FIG. 4 is a partially cut perspective view illustrating the substrate support unit and the processing container illustrated in FIG. 3 in detail.

1, 3, and 4, the substrate polishing system 2000 may include a polishing process for polishing an upper surface of the wafer 70 and a cleaning process for cleaning the surface of the wafer 70 after the polishing process. The polishing unit 1000 may proceed sequentially.

In detail, the substrate polishing unit 1000 may include a substrate support unit 100, a container unit 200, a polishing unit 300, an polishing end point detection unit 400, first and first 2 may include a processing liquid supply unit 500, 600, a brush unit 710, an aerosol unit 720, and a pad conditioning unit 800.

The substrate support unit 100 is mounted with a wafer 70 transferred from the main transfer robot 50. The substrate support unit 100 supports and fixes the wafer 70 during a polishing process and a cleaning process of the wafer 70. The substrate support unit 100 may include a spin head 110 on which the wafer 70 is seated, and a support 120 supporting the spin head 110. The spin head 110 has a generally circular shape in plan view and gradually decreases in width from an upper surface to a lower surface. In one example of the present invention, the spin head 110 has a size of an upper surface supporting the wafer 70 is smaller than the size of the wafer 70. Therefore, in the side view, the wafer 70 seated on the spin head 110 protrudes outward from the top end of the spin head 110.

The support part 120 is installed below the spin head 110. The support 120 has a generally cylindrical shape, is coupled to the spin head 110, and rotates the spin head 110 during a polishing process and a cleaning process.

The substrate support unit 100 is accommodated in the container unit 200. The container unit 200 includes first and second process bowls 210 and 220, first and second recovery vats 230 and 240, and first and second recovery tubes 251. , 252, and an elevating member 260.

In detail, the first and second processing containers 210 and 220 surround the substrate support unit 100 and provide a process space in which a polishing process and a cleaning process of the wafer 70 are performed. Upper portions of the first and second processing vessels 210 and 220 are respectively opened, and the spin head 110 is exposed through the open upper portions of the first and second processing vessels 210 and 220. In this embodiment, the first and second processing vessels 210 and 220 have a circular ring shape, but the shapes of the first and second processing vessels 210 and 220 are not limited thereto. Can have

In detail, the first processing container 210 may include a sidewall 211, a top plate 212, and a guide part 213. The side wall 211 has a generally circular ring shape and surrounds the substrate support unit 100.

An upper end of the side wall 211 is connected to the top plate 212. The upper plate 212 extends from the side wall 211, and is formed of an inclined surface that is inclined upwardly away from the side wall 211. The top plate 212 has a generally circular ring shape and is spaced apart from the spin head 110 when viewed in plan view and surrounds the spin head 110.

The guide portion 213 includes first and second guide walls 213a and 213b. The first guide wall 213a protrudes from the inner wall of the side wall 211 to face the top plate 212, and is formed of an inclined surface that is inclined downward as it moves away from the side wall, and has a circular ring shape. The second guide wall 213b extends vertically downward from the first guide wall 213a, faces the side wall 211, and has a circular ring shape. The guide part 213 has a treatment liquid scattered to the side surfaces 211 of the first processing container 210 and the inner surfaces of the upper plate 212 during the polishing process of the wafer 70. Guide to flow to the side.

The second processing container 220 is installed outside the first processing container 210. The second processing container 220 surrounds the first processing container 210 and has a size larger than that of the first processing container 210.

In detail, the second processing container 220 may include a sidewall 221 and a top plate 222. The side wall 221 has a generally circular ring shape and surrounds the side wall 211 of the first processing container 210. The side wall 221 is positioned to be spaced apart from the side wall 211 of the first processing container 210 and is connected to the first processing container 210.

An upper end of the side wall 221 is connected to the top plate 222. The upper plate 222 extends from the side wall 221 and is formed of an inclined surface that is inclined upwardly away from the side wall 221. The top plate 222 has a generally circular ring shape and is spaced apart from the spin head 110 when viewed in plan view and surrounds the spin head 110. The upper plate 222 faces the upper plate 211 of the first processing container 210 on the upper plate 211 of the first processing container 210, and the upper plate of the first processing container 210 ( 211).

Under the first and second processing vessels 210 and 220, the first and second recovery containers 230 and 240 for recovering the processing liquids used in the polishing process and the cleaning process are installed. The first and second recovery containers 230 and 240 have a generally circular ring shape and an upper portion thereof is opened. In this embodiment, the first and second recovery container 230 and 240 have a circular ring shape, but the shape of the first and second recovery container 230 and 240 is not limited thereto, and may be variously formed. Can be.

The first recovery container 230 is installed below the first processing container 210 to recover the processing liquid used in the polishing process. The second collection container 240 is installed under the second processing container 220 to recover the processing liquid used in the cleaning process.

In detail, the first recovery container 230 may include a bottom plate 231, a first sidewall 232, a second sidewall 233, and a connection part 234. The bottom plate 231 has a generally circular ring shape and surrounds the support 220. In one example of the present invention, the bottom plate 231 has a longitudinal section 'V' shape to facilitate the discharge of the treatment liquid recovered in the first recovery container 230. As a result, a ring-shaped recovery passage 231a is formed in the bottom plate 231, and the discharge and recovery of the treatment liquid are easy.

The first sidewall 232 extends vertically from the bottom plate 231 to form a first recovery space RS1 for recovering the treatment liquid. The second sidewall 233 is spaced apart from the first sidewall 232 to face the first sidewall 232. The connection part 234 is connected to an upper end of the first side wall 232 and an upper end of the second side wall 233, and is inclined upward toward the second side wall 233 from the first side wall 232. It consists of a slope. The connection part 234 guides the treatment liquid that is out of the first recovery space RS1 to the first recovery space RS1 so that the processing liquid flows into the first recovery space RS1.

The second recovery container 240 is installed outside the first recovery container 230. The second recovery container 240 surrounds the first recovery container 230 and is spaced apart from the first recovery container 230. In detail, the second recovery container 240 may include a bottom plate 241, a first sidewall 242, and a second sidewall 243. The bottom plate 241 has a generally circular ring shape, and surrounds the bottom plate 231 of the first recovery container 230. In one example of the present invention, the bottom plate 241 has a longitudinal section 'V' shape to facilitate the discharge of the treatment liquid recovered in the second recovery container 240. As a result, a ring-shaped recovery passage 241a is formed in the bottom plate 241, and the discharge and recovery of the processing liquid are easy.

The first and second sidewalls 242 and 243 extend vertically from the bottom plate 241 to form a second recovery space RS2 for recovering the treatment liquid, and have a circular ring shape. The first sidewall 242 is positioned between the first sidewall 232 and the second sidewall 233 of the first recovery container 230, and the first sidewall 232 of the first recovery container 230. Surround). The second sidewall 243 of the second recovery container 240 faces the first sidewall 242 with the bottom plate 241 interposed therebetween, and surrounds the first sidewall 242. The second sidewall 243 of the second recovery container 240 surrounds the second sidewall 233 of the first recovery container 230, and has an upper end sidewall 222 of the second processing container 220. Located outside.

During the polishing and cleaning process of the wafer 70, a vertical position between the spin head 110 and the first and second processing containers 210 and 220 is changed according to each process, and the first and second recovery times are changed. The barrels 230 and 240 recover the treatment liquid used in different processes.

Specifically, during the polishing process, the spin head 110 is disposed in the first processing container 210, and the polishing process of the wafer 70 is performed in the first processing container 210. The wafer 70 is rotated by the rotation of the spin head 110 during the polishing process. Accordingly, the processing liquid sprayed on the wafer 70 during the polishing process is scattered toward the inner surface of the side wall 211 and the upper plate 212 of the first processing container 210 by the rotational force of the wafer 70. . The processing liquid buried in the side walls 211 of the first processing container 210 and the inner surfaces of the upper plate 212 flows along the top plate 212 and the side walls 211 of the first processing container 210 in the direction of gravity. The guide part 213 is reached and flows along the inner surface of the guide part 213 in the direction of gravity to be collected in the first recovery container 230.

During the cleaning process after the polishing process, the spin head 110 is disposed below the top plate 222 of the second processing container 220 at the top of the first processing container 210 and rotates during the cleaning process. . Accordingly, the processing liquid provided to the wafer in the cleaning process is scattered to the inner surface of the upper plate 222 and the inner surface of the side wall 221 of the second processing container 220 and to the outer surface of the first processing container 210. The side wall 211 of the first processing container 210 is positioned above the bottom plate 241 of the second recovery container 240, and the processing liquid buried on the outer surface of the first processing container 210 is formed of the first processing container 210. 1 It flows along the outer surface of the processing container 210 to the gravity direction, and is recovered by the said 2nd collection container 240. In addition, the processing liquid buried on the inner surface of the second processing container 220 flows in the direction of gravity along the inner surface of the second processing container 220 and is recovered in the second collecting container.

As described above, the first recovery container 230 recovers the processing liquid used in the polishing process, and the second recovery container 240 recovers the processing liquid used in the cleaning process. Accordingly, the container unit 200 can separate and recover the processing liquid in each process step made in the container unit 200, so that the processing liquid can be reused, and the processing liquid can be easily recovered.

The first recovery container 230 is connected to the first recovery pipe 251, and the second recovery container 240 is connected to the second recovery pipe 252. The first recovery pipe 251 is coupled to the bottom plate 231 of the first recovery container 230, the first recovery pipe 251 on the bottom plate 231 of the first recovery container 230. The first recovery hole 231b is formed to communicate with. The treatment liquid recovered in the first recovery space RS1 of the first recovery container 230 is discharged to the outside through the first recovery pipe 251 via the first recovery hole 231b.

In this embodiment, the container unit 200 includes two processing vessels 210 and 220 and two collecting vessels 230 and 240, but the processing vessels 210 and 220 and the collecting vessel 230. , 240) may increase depending on the number of kinds of treatment liquids used in the polishing and washing processes and the number of kinds of treatment liquids to be separated and recovered.

The second recovery pipe 252 is coupled to the bottom plate 241 of the second recovery container 240, the second recovery pipe 252 on the bottom plate 241 of the second recovery container 240. The second recovery hole 241b is formed in communication with. The treatment liquid recovered in the second recovery space RS2 of the second recovery container 240 is discharged to the outside through the second recovery pipe 252 via the second recovery hole 241b.

In this embodiment, each of the first and second recovery pipes 251 and 252 is provided, but the number of the first and second recovery pipes 251 and 252 is the first and second recovery pipes 251 and 252. It may increase depending on the size and recovery efficiency of the second recovery container (230, 240).

On the other hand, the lifting member 260 that is vertically movable is provided on the outside of the second processing container 220. The elevating member 260 is coupled to the side wall 221 of the second processing container 220, and adjusts vertical positions of the first and second processing containers 210 and 220. In detail, the lifting member 260 may include a bracket 261, a moving shaft 262, and a driver 263. The bracket 261 is fixed to the outer wall 221 of the second processing container 220 and is coupled to the moving shaft 262. The moving shaft 262 is connected to the driver 263 and is moved in the vertical direction by the driver 263.

The elevating member 260 may include the first and second processing containers 210 and 220 when the wafer 70 is seated on the spin head 110 or lifted from the spin head 110. The first and second processing vessels 210 and 220 are lowered to protrude to the upper portion of the first and second processing vessels 210 and 220. When descending, the first and second sidewalls 232 and 233 and the connection portion 234 of the first recovery container 230 are connected to the sidewall 211 and the first and second guide walls of the first processing container 210. It is drawn into the space formed by 213a and 213b.

In addition, the elevating member 260 may process the first and second treatments to separate and recover the processing liquid used in the polishing process and the processing liquid used in the cleaning process during the polishing process and the cleaning process of the wafer 10. Lifting and lowering the vessels 210 and 220 adjusts the relative vertical position between each of the treatment vessels 210 and 220 and the spin head 110.

In this embodiment, the substrate polishing unit 1000 vertically moves the first and second processing vessels 210 and 220 so as to first and second processing vessels 210 and 220 and the spin head 110. The relative vertical position of the liver may be changed, but the relative vertical position between the first and second processing vessels 210 and 220 and the spin head 110 may be changed by vertically moving the spin head 110.

Meanwhile, the polishing unit 300, the first and second processing fluid supply units 500 and 600, the brush unit 710, the aerosol unit 720, and the pad may be disposed outside the container unit 200. The conditioning unit 800 is installed.

The polishing unit 300 polishes the surface of the wafer 70 fixed to the substrate support unit 100 by a chemical mechanical method to planarize the surface of the wafer 70. Detailed description of the configuration of the polishing unit 300 will be described in detail with reference to FIGS.

The polishing endpoint detector 400 is installed on the substrate support unit 100. The polishing endpoint detection unit 400 is fixedly installed on the upper surface of the processing chamber in which the substrate polishing unit 1000 is installed, and calculates the polishing amount by measuring the thickness of the wafer 70 after the polishing process or the cleaning process. The polishing endpoint detection unit 400 has at least five measurement points P1,..., And P5, and the measurement points P1,..., P5 have a diameter along the diameter of the wafer 70. It is located over the whole area | region of 70.

As such, the polishing endpoint detecting unit 400 is fixedly installed on the substrate support unit 100 separately from the polishing unit 300, so that the thickness of the wafer 70 may be accurately measured after the polishing process or after the cleaning process. can do. In addition, maintenance of the polishing endpoint detection unit 400 is easy, and the thickness of the wafer 70 may be measured even after the cleaning process.

Meanwhile, the first and second processing fluid supply units 500 and 600 spray processing fluids necessary for the polishing process and the cleaning process of the wafer 70 onto the wafer 70 fixed to the substrate support unit 100. do. The first processing fluid supply unit 500 is installed to face the polishing unit 300 with the container unit 200 therebetween, and is fixedly installed on the sidewall 221 of the second processing container 220. . In the polishing process or the cleaning process, the first processing fluid supply unit 500 cleans the wafer 70 by spraying the processing fluid onto the wafer 70 fixed to the spin head 110. The first processing fluid supply unit 500 may include a plurality of injection nozzles fixed on an upper side of the sidewall 221 of the second processing container 220, and each injection nozzle may be processed toward the center portion of the wafer 70. Inject fluid. The processing fluid injected from the injection nozzle may be a processing liquid for cleaning or drying the wafer 70, or may be a drying gas for drying.

In one example of the present invention, the first processing fluid supply unit 500 includes four injection nozzles, but the number of the injection nozzles increases or decreases depending on the number of types of the processing fluid used for cleaning the wafer 70. You may.

The second processing fluid supply unit 600 is installed to face the polishing unit 300 with the container unit 200 and the first processing fluid supply unit 500 interposed therebetween. The second processing fluid supply unit 600 includes a chemical liquid nozzle for injecting the processing liquid, and in the cleaning process, the processing liquid is injected onto the wafer 70 fixed to the spin head 110 to process the wafer 70. Clean. The second processing fluid supply unit 600 may swing, and injects the processing liquid in a state in which the chemical liquid nozzle is disposed on the spin head 110 through a swing operation during the cleaning process.

The brush unit 710 physically removes foreign substances on the surface of the wafer 70 after the polishing process. The brush unit 710 has a brush pad that contacts the surface of the wafer 70 to physically wipe off the foreign matter on the surface of the wafer 70, and is swingable. In the cleaning process, the brush unit 710 rotates the brush pad in a state in which the brush pad is disposed on the upper portion of the spin head 110 through a swinging motion, and the wafer 70 is fixed to the spin head 110. )).

The aerosol unit 720 is disposed on one side of the brush unit 710. The aerosol unit 720 removes foreign substances on the surface of the wafer 70 by spraying the processing liquid in the form of fine particles on the wafer 70 fixed to the spin head 110. In one example of the present invention, the aerosol unit 720 sprays the treatment liquid in the form of small particles using ultrasonic waves. The brush unit 710 is used to remove foreign particles of relatively large particles, and the aerosol unit 720 is used to remove foreign particles of relatively small particles compared to the brush unit 710.

Meanwhile, the pad conditioning unit 800 cleans and regenerates the polishing unit 300 when the polishing unit 300 is standing by at a home port. A detailed description of the configuration of the pad conditioning unit 800 will be described in detail later with reference to FIG. 14.

As described above, in the substrate polishing system 2000, since both the polishing process and the cleaning process of the wafer 70 are performed at each substrate polishing unit 1000, it is necessary to transfer the wafer to the cleaning process chamber after the polishing process. There is no need for a separate cleaning process chamber. Accordingly, the substrate polishing system 2000 may shorten the transfer time and the process time of the wafer 70, improve productivity, and reduce the footprint.

Hereinafter, the configuration of the polishing unit 300 will be described in detail with reference to the drawings.

5 is a perspective view showing the polishing unit shown in FIG. 3, FIG. 6 is a partial cutaway side view showing the polishing unit shown in FIG. 5, and FIG. 7 is a longitudinal cross-sectional view showing the polishing unit shown in FIG.

4 to 7, the polishing unit 300 may include a pressing part 310, a fluid supply part 320, a swing part 330, and a driving part 340.

Specifically, the pressing unit 310 is disposed on the wafer 70 fixed to the spin head 110 during the polishing process. The pressing unit 310 rotates in contact with the wafer 70 while spraying a chemical liquid for polishing the wafer 70 to polish the wafer 70. The fluid supply part 320 is provided above the pressing part 310. The fluid supply unit 320 provides the chemical liquid to the pressing unit 310, and receives the rotational force from the driving unit 340 through the rotating unit 330 to rotate together with the pressing unit 310.

The rotating part 330 is installed above the fluid supply part 320. The rotating part 330 may include a rod-shaped rotating case 331 and a belt-pull assembly 335 which transmits the rotational force from the driving part 340 to the fluid supply part 320. One side of the rotary case 331 is coupled to the fluid supply unit 320, the other side is coupled to the drive unit 340.

The driving unit 340 adjusts vertical positions of the first driving motor 341 for rotating the rotating unit 330, the second driving motor 342 for rotating the fluid supply unit 320, and the pressing unit 310. It may include a vertical moving unit 343.

The first driving motor 341 is coupled to the rotation case 331, and provides a rotational force to the rotation case 331. The first driving motor 341 may alternately and repeatedly provide a rotational force in a clockwise direction and a rotational force in a counterclockwise direction. Accordingly, the rotating part 330 swings by the driving part 340 with a portion coupled to the driving part 340 as a central axis. During the polishing process, the pressing unit 310 may horizontally reciprocate in an arc shape on the upper portion of the wafer 70 by the swinging operation of the rotating unit 330.

The second driving motor 342 is installed under the first driving motor 341. The second drive motor 342 provides a rotational force to the belt-pulley assembly 335, and the belt-pulley assembly 335 transmits the rotational force of the second drive motor 342 to the fluid supply unit 320. to provide. The belt-pulley assembly 335 may be embedded in the rotation case 331 and include a driving pulley 332, a driven pulley 333, and a belt 334. The driving pulley 332 is installed on an upper portion of the first driving motor 341, and is coupled to one side of the vertical arm 344 passing through the first driving motor 341. The second driving motor 342 is coupled to the other side of the vertical arm 344.

The driven pulley 333 is disposed to face the driving pulley 332 and is installed on the fluid supply part 320 to be coupled to the fluid supply part 320. The driving pulley 332 and the driven pulley 333 are connected to each other through the belt 334, and the belt 334 is wound around the driving pulley 332 and the driven pulley 333.

The rotational force of the second drive motor 342 is transmitted to the drive pulley 332 through the vertical arm 344, whereby the drive pulley 332 rotates. The rotational force of the driving pulley 332 is transmitted to the driven pulley 333 through the belt 334, and thus, the driven pulley 333 rotates. The rotational force of the driven pulley 333 is transmitted to the fluid supply part 320, and thus, the pressing part 310 and the fluid supply part 320 rotate.

The vertical moving part 343 is installed behind the first driving motor 341 and the second driving motor 342. The vertical moving part 343 may include a ball screw 343a, a nut 343b, and a third drive motor 343c. The ball screw 343a has a rod shape and is installed perpendicular to the ground. The nut 343b is fitted to the ball screw 343a and is fixed to the second drive motor 342. The third driving motor 343c is installed under the ball screw 343a. The third driving motor 343c may be coupled to the ball screw 343a and may provide a clockwise rotational force and a counterclockwise rotational force to the ballstream 343a. The ball screw 343a is rotated clockwise or counterclockwise by the third drive motor 343c. The nut 343b moves up and down along the ball screw 343a by the rotation of the ball screw 343a. Accordingly, the second driving motor 342 coupled to the nut 343b is connected to the nut (343b). 343b) to move up and down. The first driving motor 341 and the rotating part 330 are moved up and down by the vertical movement of the second driving motor 342, so that the fluid supply part 320 and the pressing part 310 are also moved up and down. do.

In this embodiment, the vertical moving part 343 is provided with a ball screw 343a, a nut 343b and a third drive motor 343c to provide vertical movement force in a linear motor manner, but with a cylinder It may also provide vertical movement force.

Meanwhile, the swing driver 341, the spin driver 342, the ball screw 343a, the nut 343b, and the vertical arm 344 are embedded in the drive case 345, and the drive case 345 is It has a long rod shape in the vertical direction.

On the other hand, the fluid supply unit 320 provides the chemical liquid for polishing the wafer to the pressing unit 310, and rotates by the rotational force provided from the driving unit 340 to rotate the pressing unit 310.

In detail, the fluid supply part 320 includes a housing 321, a rotation shaft 322, first and second bearings 323a and 323b, a fixed shaft 324, and first and second chemical tubes 326a and 326b. , An air injection pipe 327, and first and second rotary lip seals 328a and 328b.

The housing 321 has a generally cylindrical tubular shape, and an upper end is inserted into the rotating case 331 of the rotating part 330 to be coupled to the rotating case 331, and a lower end thereof is coupled to the pressing part 310. do.

The rotating shaft 322 is provided in the housing 321 and is spaced apart from the housing 321. The rotating shaft 322 is formed of a hollow tube extending in the longitudinal direction of the housing 321. The upper end of the rotating shaft 322 is inserted into the driven pulley 333 of the rotating part 330 to engage with the driven pulley 333, the rotating shaft 322 is rotated by the rotation of the driven pulley 333. . The lower end of the rotating shaft 322 is coupled to the pressing portion 310, the pressing portion 310 is rotated by the rotation of the rotating shaft 322. That is, the rotational force of the second drive motor 342 is vertical arm 344-> drive pulley 332-> belt 334-> driven pulley 333-> rotation shaft 322-> pressurizing part 310 The pressing unit 310 is rotated based on the center of gravity.

The first and second bearings 323a and 323b are interposed between the housing 321 and the rotation shaft 322. The first and second bearings 323a and 323b connect the housing 321 and the rotation shaft 322 and support the rotation shaft 322 so that the rotation shaft 322 rotates stably. The first bearing 323a is located adjacent to the rotating part 330, and the second bearing 323b is located adjacent to the pressing part 310. The inner rings of the first and second bearings 323a and 323b are fitted to the rotation shaft 322 to rotate together with the rotation shaft 322, and the outer rings are coupled to the housing 321 to rotate when the rotation shaft 322 is rotated. I never do that. Therefore, only the rotation shaft 322 rotates, and the housing 321 does not rotate.

The fixed shaft 324 is installed in the rotation shaft 322. The fixed shaft 324 is made of a hollow tube extending in the same direction as the rotating shaft 332. The fixed shaft 324 is spaced apart from the rotating shaft 322 and does not rotate when the rotating shaft 332 rotates. The upper end of the fixed shaft 324 is inserted into the rotary case 331, coupled to the first shaft bracket 325a fixed to the rotary case 331 so that the fixed shaft 324 is the rotary case 331 It is fixed to). The lower end of the fixed shaft 324 is inserted into the pressing portion 310, and is coupled to the second shaft bracket 325b installed in the pressing portion 310 so that the fixed shaft 324 is the pressing portion 310 Is fixed to.

The first and second chemical liquid tubes 326a and 326b are installed in the fixed shaft 324. The first and second chemical liquid tubes 326a and 326b extend in the same direction as the fixed shaft 324 in the fixed shaft 324 and are disposed in parallel to each other. The first and second chemical liquid tubes 326a and 326b provide a transfer flow path of the chemical liquid used in the polishing process, and an output end for discharging the chemical liquid is located in the pressing unit 310.

An input end of the first chemical tube 326a is connected to a first chemical supply line 83a, and the first chemical supply line 83a supplies a first chemical CL1 used to polish a wafer. 1 is connected to the chemical supply unit (81). The first chemical liquid tube 326a receives the first chemical liquid CL1 from the first chemical liquid supply part 81 through the first chemical liquid supply line 83a.

An input end of the second chemical tube 326b is connected to a second chemical liquid supply line 83b, and the second chemical liquid supply line 83b supplies a second chemical liquid CL2 used to polish the wafer. It is connected to the chemical liquid supply part 82. The second chemical liquid tube 326b receives the second chemical liquid CL2 from the second chemical liquid supply part 82 through the second chemical liquid supply line 83b.

In this embodiment, the first and second chemical liquids CL1 and CL2 may be different kinds of chemical liquids, or may be the same chemical liquid. Examples of the chemical liquids CL1 and CL2 discharged from the first and second chemical liquid tubes 326a and 326b include a slurry for polishing a wafer.

In an example of the present invention, the first and second chemical liquid tubes 326a and 326b are connected to the first and second chemical liquid supply lines 83a and 83b respectively installed through the rotating case 331.

On the other hand, the air injection pipe 327 is installed on the upper end of the housing 321. The air injection pipe 327 is connected to the pad pressure control unit 900, and receives air from the pad pressure control unit 900. In one example of the present invention, the air injection pipe 327 is located inside the rotary case 331.

The air injection pipe 327 communicates with the first air flow path AFP1 formed in the housing 321, and the air injected into the air injection pipe 327 flows into the first air flow path AFP1. The first air flow path AFP1 is formed inside the wall of the housing 321 and extends along the longitudinal direction of the housing 321 from an upper end of the housing 321. An output end of the first air flow path AFP1 communicates with a second air flow path AFP2 formed between the housing 321 and the rotation shaft 322, and the air provided to the first air flow path AFP1 is formed in the first air flow path AFP1. 2 flows into the air flow path AFP2.

The second air flow path AFP2 is defined by the first and second rotary lip seals 328a and 328b. The first and second rotary lip seals 328a and 328b are interposed between the housing 321 and the rotation shaft 322 to seal a space between the housing 321 and the rotation shaft 322. The first and second rotary lip seals 328a and 328b face each other and have a ring shape. The first rotary lip seal 328a is positioned below the first bearing 323a and adjacent to the first bearing 323a. The second rotary lip seal 328b is installed below the first rotary lip seal 328a and is spaced apart from the first rotary lip seal 328a. A space in which the first rotary lip seal 328a and the second rotary lip seal 328b are spaced apart from each other is provided to the second air flow path AFP2, and the second air flow path AFP2 moves the rotation shaft 322. Surround.

The second air flow path AFP2 communicates with a third air flow path AFP3 formed in the wall of the rotation shaft 322, and the air provided to the second air flow path AFP2 is connected to the third air flow path AFP3. Inflow. The third air flow path AFP3 extends from a point connected with the second air flow path AFP2 in the longitudinal direction of the rotation shaft 322 to a lower end of the rotation shaft 322. The air injected from the pad pressure controller 900 passes through the air inlet tube 327-> first air flow path AFP1-> second air flow path AFP2-> third air flow path AFP3. By the pressing unit 310 is provided.

The pressing unit 310 is installed below the fluid supply unit 320, and the pressing unit 310 rotates while pressing the surface of the wafer to polish the surface of the wafer. In the polishing process, the pressure at which the pressing unit 310 pressurizes the wafer is controlled by the pressure of air introduced into the pressing unit 310 through the third air flow path AFP3.

The pressing unit 310 may include a polishing pad 311, a polishing body 312, a pad holder 313, a clamp member 314, a coupling plate 315, a bellows 316, a cover 317, and a chemical nozzle ( 318).

The polishing pad 311 has a plate shape and has a generally circular ring shape. The polishing pad 311 is rotated while the lower surface is in contact with the upper surface of the wafer during the polishing process to polish the wafer. The polishing pad 311 has a diameter smaller than the diameter of the wafer, and polishes the wafer while swinging by the driving unit 340 during the polishing process. As such, since the polishing pad 311 has a smaller size than the wafer, the polishing unit 300 may locally polish the wafer and prevent over-polishing in a specific region.

The polishing body 312 is provided on the polishing pad 311. The polishing body 312 has a generally circular ring shape and is coupled to the fixed shaft 324 of the fluid supply part 320. Specifically, the polishing body 312 may include a polishing housing 312a, a lower plate 312b and an upper plate 312c.

The polishing housing 312a has a generally cylindrical shape, and the lower plate 312b is installed at a lower portion thereof. The lower plate 312b has a generally circular ring shape and has the same size as the polishing pad 311. The lower plate 312b is coupled to the lower portion of the polishing housing 312a to seal the lower portion of the polishing housing 312a.

The polishing pad 311 is installed below the lower plate 312b. The pad holder 313 is interposed between the polishing pad 311 and the lower plate 312b. The pad holder 313 detachably fixes the polishing pad 311 to the polishing body 312. That is, the bottom surface of the pad holder 313 is coupled to the top surface of the polishing pad 311, and the top surface is detachably coupled to the lower plate 312b by the clamp member 314.

The clamp member 314 is interposed between the lower plate 312b and the pad holder 313 to securely couple the pad holder 313 to the lower plate 312b using a magnetic force. Specifically, the clamp member 314 includes a magnet 314a, a clamp plate 314b, and a screw 314c. The magnet 314a is interposed between the clamp plate 314b and the lower plate 312b and has a generally circular ring shape. In one example of the present invention, the clamp member 314 includes one magnet 314a having a ring shape, but the number of the magnets 314ba is equal to the size of the clamp member 314 and the magnet 314a. The size of the magnet 314a may be changed in various forms. The clamp plate 314b faces the lower plate 312b and is coupled to the lower plate 312b using the screw 314c. Since the clamp plate 314b is made of a metal material having no magnetic material, for example, aluminum, it does not react to the magnet 312a. The clamp plate 314, whereas the pad holder 313 is made of a material having a magnetic material, such as stainless steel or carbon steel, the lower plate by the magnetic force of the magnet 312a Coupled to 312b.

As described above, since the clamp member 314 fixes the pad holder 313 to the lower plate 312b by using magnetic force, it is easy to attach or detach the pad holder 313 to the lower plate 312b. . In particular, since the polishing pad 311 is a consumable, periodic replacement is necessary. Therefore, the process of fixing the pad holder 313 to the lower plate 312b and the process of separating from the lower plate 312b frequently occur. Since the pressing unit 310 is coupled to the pad holder 313 and the lower plate 312b by the magnetic force of the clamp member 314, it is possible to shorten the time required to replace the polishing pad 311. have. Accordingly, the pressing unit 310 may shorten the process waiting time and improve productivity.

In one example of the present invention, the clamp plate 314b is formed with an insertion groove into which the magnet 314a is partially inserted into a portion where the magnet 314a is disposed. In addition, an insertion groove into which the magnet 314a and the clamp plate 314b are inserted is formed at a portion of the lower plate 312b to which the flange member 314 is coupled.

Although only one clamp member 314 is illustrated in FIG. 9, the pad holder 3130 may be coupled to the lower plate 312b by using a plurality of clamp members 314.

On the other hand, the lower plate 312b is coupled to the upper plate 312c. The upper plate 312c is disposed above the lower plate 312b and disposed to face the lower plate 312b. The upper plate 312c is installed in the polishing housing 312a to seal an upper portion of the polishing housing 312b and has a generally circular ring shape.

The upper plate 312c is fixedly coupled to the coupling plate 315 provided on the upper surface. The coupling plate 351 is coupled to the rotation shaft 322 of the fluid supply unit 320 and rotates together with the rotation shaft 322. Accordingly, the entire pressing unit 310 is rotated. The coupling plate 351 has a generally circular plate shape and has a fourth air flow path AFP through which air discharged from the rotation shaft 322 flows. The fourth air flow path AFP communicates with the third air flow path AFP3 of the rotation shaft 322, and air is introduced through the third air flow path AFP3. Air introduced into the fourth air flow path APF4 is injected into the bellows 316.

The bellows 316 is installed in a space in which the lower plate 312b and the upper plate 312c are spaced apart from each other in the polishing housing 312a and are made of a metal material. The bellows 316 is stretchable in the vertical direction by the pressure of air provided from the fourth air flow path AFP4. The bellows 316 may be extended so that the polishing pad 311 closely adheres to the wafer during the polishing process. When the polishing process is performed while the polishing pad 311 is closely adhered to the wafer, the polishing of the wafer is uniformly efficient. It can proceed to.

The process of pressing the wafer by the polishing pad 311 will now be described in detail.

First, the pressing unit 310 is disposed on the wafer 70 and waits for the polishing process. In the air, the bellows 316 is contracted by the vacuum pressure provided from the pad pressure control unit 900. Accordingly, the lower plate 312b moves toward the upper plate 312c, and the polishing pad 311 is spaced apart from the wafer 70. The upper plate 312c is provided with an internal stopper 312d for adjusting the contraction degree of the bellows 316. The inner stopper 312d protrudes from the lower surface of the upper plate 312c and contacts the lower plate 312b when the bellows 316 contracts. The stopper 312d prevents the lower plate 312b from moving upwards by more than an appropriate distance when the bellows 316 is contracted so that the gap between the lower plate 312b and the upper plate 312c is less than or equal to an appropriate interval. Prevent narrowing.

In the polishing process, air is injected into the air injection pipe 327 from the pad pressure adjusting unit 900, and the air injected into the air injection pipe 327 passes through the first to fourth air flow paths AFP1 and AFP2. , AFP3, AFP4 are sequentially injected to the bellows 316 via. The bellows 316 is relaxed by the pressure of the injected air, thereby increasing the length of the bellows 316 when it is contracted. The polishing pad 311 is in contact with the wafer 70 by the relaxation of the bellows 316, and the pressing unit 310 is in a state in which the polishing pad 311 is in contact with the wafer 70. The wafer 70 is polished by rotating about the central axis of the polishing pad 311.

Since the pressing unit 310 presses the wafer 10 by the bellows 316, the polishing pad 311 may tilt the polishing pad 311. Since the wafer 70 includes a plurality of patterned thin films, the top surface may not be formed flat. In the polishing process, the polishing pad 311 may be tilted by the bellows 316, thereby improving adhesion to the surface of the wafer 70. In one example of the present invention, the tilting angle TA of the polishing pad 311 is about ± 1 degree.

The pressure for pressing the wafer 70 is adjusted according to the pressure of the air injected into the bellows 316 of the polishing pad 311. The air pressure of the bellows 316 is adjusted by the pad pressure adjusting unit 900, and the process of adjusting the air pressure will be described later in the description of the configuration of the pad pressure adjusting unit 900.

On the other hand, the cover 317 is installed on the upper portion of the polishing body 312 to cover the upper portion of the polishing body 312. The cover 317 is coupled to the upper end of the polishing housing 312a, and a space for accommodating the coupling plate 315 is provided therein. An opening 317a is formed in the central portion of the cover 317, and a portion of the coupling plate 315 protrudes outwardly through the opening 317a to engage with the rotation shaft 322. The surface defining the opening 317a is spaced apart from the coupling plate 315 inserted into the opening 317a for tilting the polishing pad 311.

Lower ends of the fixed shaft 324 and the first and second chemical tubes 326a and 326b are inserted into holes formed in the central portions of the coupling plate 317, the upper plate 312c and the lower plate 312b, respectively. do. The second shaft bracket 325b is interposed between the upper plate 312c and the fixed shaft 324. The second shaft bracket 325b is coupled to the upper plate 312c and fixedly coupled to the lower end of the fixed shaft 324 to fix the fixed shaft 324 to the upper plate 312c. The second shaft bracket 325b is coupled to the upper plate 312c by using a bearing (not shown), whereby the upper plate 312c is rotatably coupled to the second shaft bracket 325b. do.

The fixed shaft 324 and the first and second chemical liquid tubes 326a and 326b inserted into the pressing unit 310 are coupled to the chemical liquid nozzle 318. The chemical liquid nozzle 318 is inserted into a hole formed in the center of the pad holder 313 and is coupled to the pad holder 313. The input end of the chemical liquid nozzle 318 is coupled to the fixed shaft 324 and the first and second chemical liquid tubes 326a and 326b, and communicates with the output ends of the first and second chemical liquid tubes 326a and 326b. do. The output end of the chemical nozzle 318 is exposed to the outside through the pad hole 311a formed at the center of the polishing pad 311, and is provided from the first and second chemical tube 326a, 326b during the polishing process. The first and second chemical liquids CL1 and CL2 are injected onto the wafer 70. In one embodiment of the present invention, the chemical liquid nozzle 318 is a flow path through which the first chemical liquid CL1 provided from the first chemical liquid tube 326a flows and the second chemical liquid CL2 provided from the second chemical liquid tube 326b. These flow paths are formed separately from each other.

In the polishing process, the fixed shaft 324, the first and second chemical tubes 326a and 326b, and the chemical nozzle 318 do not rotate, and the polishing pad 311 and the pad holder 313 Rotate As described above, since the pad holder 313 rotates while the chemical liquid nozzle 318 is fixed, the chemical liquids CL1 and CL2 ejected from the chemical liquid nozzle 318 are separated from the pad holder 313 and the chemical liquid nozzle. It can be introduced into the gap between 318 to generate foreign matter. Since the foreign matter generated between the pad holder 313 and the chemical nozzle 318 may fall on the wafer 70 during the polishing process, it may cause poor polishing and contamination of the wafer 70.

In order to prevent this, the pressing unit 310 may further include an O-ring 319 interposed between the chemical nozzle 318 and the pad holder 313. The O-ring 319 surrounds the chemical liquid nozzle 318 and prevents the chemical liquids CL1 and CL2 injected from the chemical liquid nozzle 318 from flowing into the pressurizing part 310. Since the O-ring 319 is prone to wear due to the friction caused by the rotation of the pad holder 313, it should be replaced periodically. The o-ring 319 may be replaced with the replacement of the polishing pad 311.

Meanwhile, the polishing unit 300 further includes a rinse member 350 that prevents the first and second chemical liquids CL1 and CL2 injected onto the wafer 70 from being cured on the wafer 70 during the polishing process. can do.

FIG. 8 is a perspective view of the rinse member shown in FIG. 5. FIG.

9 and 13, the rinse member 350 is installed at one side of the fluid supply part 320, and sprays a rinse liquid RL such as ultrapure water or pure water onto the wafer during the polishing process to the wafer 70. The injected first and second chemical liquids CL1 and CL2 are prevented from curing.

Specifically, the rinsing member 350 may include first and second rinse nozzles 351 and 352 and a connection pipe 353 connected to an input terminal of the first and second rinse nozzles 351 and 352. . The connection pipe 353 is connected to the rinse supply line 85, and the rinse supply line 85 is connected to the rinse liquid supply unit 84. The rinse liquid supply unit 84 discharges the rinse liquid RL to the rinse supply line 85, and the rinse supply line 85 provides the rinse liquid RL to the connection pipe 353. . The connection pipe 353 provides the rinse liquid RL to the first and second rinse nozzles 351 and 352, and the first and second rinse nozzles 351 and 352 are rinsed on the wafer. Spray the liquid RL.

As described above, the polishing unit 300 includes the rinsing member 350 which injects the rinse liquid RL onto the wafer, whereby the first and second chemical liquids CL1, which are injected into the wafer during the polishing process. To prevent hardening of CL2). Particularly, in the case of the high speed polishing process in which the rotational speed of the polishing pad 311 rises to about 800 RPM, the slurry sprayed on the wafer for the polishing process forms a thinner film than the low speed polishing process. The slurry on the wafer is easy to cure. On the other hand, in the low speed polishing process, the slurry sprayed on the wafer during the polishing process may accumulate on the edge portion of the wafer, and the slurry may be cured in a band shape on the edge portion of the wafer.

In order to prevent hardening of the slurry, the rinse member 350 sprays the rinse liquid RL onto the wafer while the polishing pad 311 rotates to polish the wafer. Accordingly, the polishing unit 300 may prevent contamination of the wafer and polishing failure due to slurry hardening, and thus may improve the yield of the product.

In this embodiment, the rinse member 350 includes two rinse nozzles 351 and 352, but the number of the rinse nozzles 351 and 352 is a process efficiency and the injection amount of the rinse nozzles 351 and 352. It may increase or decrease depending on.

The rinse member 350 is fixed to one side of the fluid supply part 320 by a fixing bracket 360. That is, the top surface of the fixing bracket 360 is fixedly coupled to the rotating part 330, and the rinsing member 350 is fixedly coupled to the side of the fixing bracket 360.

Referring again to FIGS. 5 and 8, the pressure at which the polishing unit 300 pressurizes the wafer is controlled by the pad pressure adjusting unit 900. The pad pressure regulator 900 may include an air provider 910, a main line 920, a regulator 930, an electro-pneumatic regulator 940, a first valve 950, and a pressure gauge. 960, a vacuum member 970, a sub line 980, and a second valve 990.

In detail, the air providing unit 910 discharges air to be provided to the bellows 316 of the pressing unit 310 to the main line 920. The main line 920 has an input terminal connected to the air supply unit 910 and an output terminal connected to the air injection pipe 327. The main line 920 provides air injected from the air supply unit 910 to the air injection pipe 327 during the polishing process. Accordingly, the bellows 316 is relaxed. In addition, the main line 920 provides a vacuum pressure supplied from the vacuum member 970 to the air inlet tube 327 when the polishing unit 300 is in standby. Accordingly, the bellows 316 is contracted.

The regulator 930, the electric regulator 940, the first valve 950, and the pressure gauge 960 are sequentially installed on the main line 920. The regulator 930 reduces the pressure of the air provided from the air supply unit 910 to the main line 920 to an appropriate pressure. The air decompressed by the regulator 930 moves to the electric regulator 940. The electric regulator 940 automatically adjusts the pressure of the air decompressed by the regulator 930 to a preset pressure during the polishing process. The air in the main line 920 moves to the first valve 950 via the electro-pneumatic regulator 940. The first valve 950 supplies and blocks air injected into the main line 920 to the air injection pipe 327 through an on / off operation. The pressure gauge 960 is installed between the first valve 950 and the air injection pipe 327 to measure the final pressure of air provided to the air injection pipe 327.

The pad pressure adjusting unit 900 controls the final pressure of the air provided to the air injection pipe 327 to adjust the pressure of the polishing unit 300 to pressurize the wafer. That is, the polishing unit 300 is the pressure of the air injected into the bellows 316 according to the final pressure of the air provided from the pad pressure control unit 900 is adjusted, the bellows 316 of the internal air The degree of relaxation depends on the pressure. That is, the higher the pressure of the air injected into the bellows 316, the more the bellows 316 is relaxed, and accordingly, the pressure at which the polishing pad 311 pressurizes the wafer increases. On the other hand, the lower the pressure of the air injected into the bellows 316, the less the bellows 316 is relaxed, and thus, the pressure at which the polishing pad 311 pressurizes the wafer decreases.

In particular, the pad pressure adjusting unit 900 adjusts the final pressure of the air according to the horizontal position of the polishing pad 311 on the wafer during the polishing process. That is, the electric regulator 940 is electrically connected to the controller 60, and the controller 60 controls the electric regulator 940 so that the final pressure of the air is the polishing pad 311 on the wafer. According to the horizontal position of), adjust it to be equal to the reference pressure set corresponding to the corresponding position. The controller 60 divides the wafer into a plurality of adjustment sections, and sets an appropriate reference pressure for each adjustment section.

As described above, the pad pressure controller 900 adjusts the final pressure of the discharged air by the controller 60 for each adjustment section of the wafer. As a result, the pressure at which the polishing pad 311 pressurizes the wafer is adjusted for each adjustment section of the wafer. Accordingly, the polishing unit 300 may prevent over-polishing in a specific region of the wafer and uniformly polish the wafer.

In addition, the controller 60 may be electrically connected to the pressure gauge 960. The pressure gauge outputs the final air pressure value of the main line 920 and provides it to the controller 60. The controller 60 may be configured based on a pressure value currently measured by the pressure gauge 900 and a reference pressure value corresponding to a point at which the polishing pad 311 is currently positioned on the wafer when the final pressure of the air is adjusted. The pressure of the polishing pad 311 is adjusted to be equal to the reference pressure.

As such, the control unit 60 adjusts the final pneumatic pressure of the main line 920 based on the pressure value measured by the pressure gauge 960, so that the pressurized pressure of the polishing unit 300 during the polishing process is currently polished. The pad 311 can be accurately adjusted to be equal to the reference pressure of the adjustment section in which the pad 311 is located.

The main line 920 is connected to the sub line 980. The sub line 980 is connected to the vacuum member 970 that provides a vacuum pressure, and is connected between a point where the pressure gauge 960 is connected on the main line 920 and a point where the first valve 950 is installed. Connected. The sub line 980 provides a vacuum pressure provided from the vacuum member 970 to the fluid supply part 320 through the main line 920. The vacuum pressure provided from the pad pressure adjusting unit 900 is provided to the bellows 316 through the air injection pipe 327 and the first to third air flow paths AFP1, AFP2, and AFP3. The bellows 316 is lowered in the internal pressure by the vacuum pressure provided from the pad pressure adjuster 900, as a result, the bellows 316 is contracted.

The sub line 980 is provided with a second valve 990 for controlling whether the vacuum pressure provided to the air injection pipe 327 is blocked and supplied.

On the other hand, a predetermined polishing pattern is formed on the surface of the polishing pad 311 in contact with the wafer to improve the efficiency of the polishing process. The polishing pattern is gradually worn out by friction with the wafer in the process of polishing the wafer, and the chemical liquids used in the polishing process may be cured in the polishing pattern. The pad conditioning unit 800 (see FIG. 2) regenerates the polishing pad 311 by polishing the surface of the polishing pad 311.

Hereinafter, a process of polishing the wafer by the substrate polishing unit 1000 will be described in detail with reference to the accompanying drawings.

9 is a flowchart illustrating a substrate polishing method according to an exemplary embodiment of the present invention, and FIG. 10 is a perspective view illustrating an operating state in which the polishing unit illustrated in FIG. 4 polishes a wafer.

3, 9, and 10, first, the main transfer robot 50 (see FIG. 1) pulls the wafer 70 out of the buffer unit 30 to spin head 110 of the substrate support member 100. The wafer 70 is seated on the wafer, and the lifting unit 260 lifts the first and second processing containers 210 and 220 to position the spin head 10 in the first processing container 210. (Step S110).

Subsequently, the driving unit 340 of the polishing unit 300 positions the pressing unit 310 adjacent to the wafer 70 on the wafer 70 (step S120).

The polishing unit 300 sprays the first and second chemical liquids CL1 and CL2 onto the wafer 70, and simultaneously polishes the polishing pad 311 of the pressing unit 310 to the surface of the wafer 70. In step S130, the wafer 70 is polished by rotating about the central axis of the polishing pad 311 in a state of contacting the substrate. In the polishing process, the first and second chemical liquids CL1 and CL2 are sprayed from the chemical liquid nozzle 318 of the pressing unit 310, and the polishing pad 311 swings simultaneously with the rotation.

In this embodiment, the substrate polishing unit 1000 polishes the wafer 70 while the polishing unit 300 sprays the first and second chemical liquids CL1 and CL2. However, the polishing unit 300 does not spray the first and second chemical liquids CL1 and CL2, but separate chemical liquid spray units, for example, the first processing liquid supply unit 500 (see FIG. 3), The first and second chemical liquids CL1 and CL2 may be sprayed from the second processing liquid supply unit 600 to polish the wafer 70.

While the pressing unit 310 rotates to spray the chemicals CL1 and CL2 to polish the wafer 70, the rinse member 350 may spray the rinse liquid onto the wafer 70. . Accordingly, the polishing unit 300 may prevent hardening of the chemical liquids CL1 and CL2 injected into the wafer 70 during the polishing process, and simultaneously polish and clean the wafer 70.

When the polishing process by the polishing unit 300 is completed, the polishing end point detection unit 400 measures the thickness of the wafer 70 for each measurement point (P1, ..., P5) (step S140). The polishing amount of the wafer 70 may be calculated based on a result measured by the polishing endpoint detecting unit 400, and the polishing amount of the wafer 70 may be equal to a target value based on the calculated polishing amount. ) Control the driving.

Thereafter, the wafer 70 is cleaned (step S150).

Briefly looking at the process of cleaning the wafer 70 as follows. First, the brush unit 710 physically wipes the upper surface of the wafer 70. In this case, the spin head 110 is located in the first processing container 210. Thereafter, the elevating unit 260 lowers the first and second processing containers 210 and 220 to move the wafer 70 into the upper portion of the first processing container 210 in the second processing container 220. Place it in Subsequently, the first processing fluid supply unit 500 or the second processing fluid supply unit 600 sprays the processing liquid onto the wafer 70 to clean the wafer 70. Subsequently, the aerosol unit 720 sprays a processing fluid onto the wafer 70 to remove foreign substances remaining on the wafer 70.

Subsequently, the wafer 70 is rinsed and dried. A rinse liquid and a drying fluid for rinsing the wafer 70 may be injected from one of the first and second processing fluid supply units 500 and 600.

As described above, since the substrate polishing unit 1000 is sequentially polished and cleaned in the container unit 200, the substrate polishing unit 1000 may shorten the transfer time and the process time of the wafer 70. , Improve productivity.

In addition, the substrate polishing unit 1000 may be formed in a processing container in which the polishing process and the brush process of the wafer 70 are different from the cleaning process of the wafer 70 using a fluid. Accordingly, the substrate polishing unit 1000 may separate and recover the processing liquid used in the polishing process and the processing liquid used in the cleaning process.

When the cleaning process is completed, the main transfer robot 50 (see FIG. 1) unloads the wafer 70 on the spin head 110 and loads the wafer 70 into the buffer unit 30 (see FIG. 1). S160). The index robot 20 (see FIG. 1) pulls out the wafer 70 processed in the substrate polishing unit 1000 from the buffer unit 30 and loosens the loaded / unloading unit 10 (see FIG. 1). 12a, 12b, 12c, and 12d (see Fig. 1). After the polishing and cleaning processes are completed, the wafers are transferred to the outside in units of the pulls 12a, 12b, 12c, and 12d.

In this embodiment, the polishing endpoint detection unit 400 measures the thickness of the wafer 70 after the polishing process is completed, but measuring the thickness of the wafer 70 for measuring the polishing amount improves the accuracy of the inspection. In order to achieve this, the cleaning process of the wafer 70 may be completed.

Although described with reference to the embodiments above, those skilled in the art will understand that the present invention can be variously modified and changed without departing from the spirit and scope of the invention as set forth in the claims below. Could be.

1 is a view schematically showing a sheet type polishing system according to an embodiment of the present invention.

FIG. 2 is a side view showing the sheet type polishing system shown in FIG. 1.

3 is a perspective view illustrating the substrate polishing unit illustrated in FIG. 1.

4 is a partial cutaway perspective view specifically showing the substrate support unit and the processing container shown in FIG. 3.

FIG. 5 is a perspective view illustrating the polishing unit illustrated in FIG. 3.

FIG. 6 is a partial cutaway side view of the polishing unit shown in FIG. 5. FIG.

7 is a longitudinal cross-sectional view of the polishing unit shown in FIG.

FIG. 8 is a perspective view of the rinse member shown in FIG. 5. FIG.

9 is a perspective view of the pad conditioning unit shown in FIG. 3.

10 is a flowchart illustrating a substrate polishing method according to an embodiment of the present invention.

11 is a perspective view illustrating an operating state in which the polishing unit illustrated in FIG. 4 polishes a wafer.

Explanation of symbols on the main parts of the drawings

100: substrate support member

200: container unit

300: polishing unit

400: polishing endpoint detection unit

500: first processing liquid supply unit

600: second processing liquid supply unit

710: Brush Unit

720: aerosol unit

800: Pad Conditioning Unit

1000: substrate polishing part

Claims (14)

A substrate support member on which a substrate is mounted and which rotates the substrate; A polishing unit for polishing a substrate seated on the substrate support member; And And a polishing end point detection unit fixedly installed on the substrate support member and detecting an end point of polishing of the substrate seated on the substrate support member. The method of claim 1, And the polishing endpoint detecting unit has a plurality of measurement points located along the diameter of the substrate and detects the polishing endpoint for each measurement point. The method of claim 2, wherein the polishing unit, A polishing pad disposed on an upper surface of the substrate seated on the substrate supporting member during the polishing process, the polishing pad rotating to be in contact with the upper surface of the substrate to polish the substrate, the polishing pad having a size smaller than that of the substrate; And And a driving unit for rotating the polishing pad. The method of claim 3, The polishing unit further includes a chemical liquid nozzle positioned at a central portion of the polishing pad and spraying the chemical liquid on a substrate seated on the substrate support member. And the polishing pad provides a pad hole for exposing the chemical liquid nozzle. The method according to any one of claims 1 to 4, A container unit accommodating the substrate supporting member and providing a space in which the substrate polishing and cleaning processes are performed; And And a processing fluid supply unit which is provided on one side of the container unit and injects a processing fluid used in the polishing step or the cleaning step onto a substrate seated on the substrate support member. The method of claim 5, wherein the container unit, And a plurality of processing containers each of which surrounds the substrate supporting member, each of which has a columnar shape, an upper portion of which is open, and which is arranged in a stacked structure. The method of claim 6, wherein the plurality of processing vessels, A first processing container accommodating the substrate supporting member, the first processing container having a columnar shape, and having an upper portion open; And At least one second processing container spaced apart from the first processing container, surrounding the first processing container, having the same shape as the first processing container, and having an upper surface located above the upper surface of the first processing container. Substrate polishing apparatus, characterized in that. The substrate polishing apparatus according to claim 6, wherein the container unit further includes a lifting member for vertically moving the plurality of processing containers. The method of claim 6, wherein the container unit, And a plurality of collecting containers located below the plurality of processing containers, corresponding to the plurality of processing containers, for recovering a processing liquid used in the polishing process or the cleaning process from a corresponding processing container. A substrate polishing apparatus. 10. The method of claim 9, And the plurality of recovery containers are located in one-to-one correspondence with the plurality of processing containers. Mounting a substrate on the substrate support member; Disposing a polishing pad of a polishing unit on an upper surface of the substrate; Polishing the upper surface of the substrate by rotating the substrate support member and the polishing pad; And Cleaning the substrate on which the polishing process is completed; And polishing an end point of the substrate using a polishing end point detection unit fixedly mounted on the substrate support member in at least one of the steps of polishing the substrate and cleaning the substrate. The substrate polishing method of claim 11, wherein the polishing endpoint detection unit has a plurality of measurement points located along the diameter of the substrate, and the polishing endpoint is detected for each measurement point. The method of claim 12, The polishing process and the cleaning process of the substrate are made in one container unit in which the supporting member of the substrate is accommodated, The container unit may be configured to provide a plurality of processing containers each having a columnar shape, each having a columnar shape, and having an open top and arranged in a stacked structure so that the polishing process and the cleaning process are performed in different spaces. Substrate polishing method. The method of claim 13, And separating and recovering the processing liquid used in the polishing process and the processing liquid used in the cleaning process through the plurality of processing vessels during the polishing process and the cleaning process of the substrate.

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