JP2007324610A - Device and method for substrate processing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and method for substrate processing capable of processing a hydrophobic wafer using a fluid mixing nozzle. <P>SOLUTION: A substrate processing device is provided with a processing liquid supply means 66 which supplies process liquid, an inert gas supply means 67 which supplies an inert gas, and a two-phase fluid mixing nozzle 65 which discharges processing liquid pressurized by the inert gas to a substrate, and processes the substrate by the processing liquid. The processing liquid supply means 66 is provided with fluid mixing means 12 which mixes liquid which reduces a surface tension force of the processing liquid and the processing liquid. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for cleaning a substrate such as a semiconductor wafer or glass for an LCD substrate.

  For example, in a semiconductor device manufacturing process, a processing system including a substrate processing apparatus that performs etching processing and / or ashing processing on a semiconductor wafer or the like (hereinafter referred to as a wafer or the like) is used. This processing system is provided with a single-wafer type substrate cleaning processing apparatus that removes polymers, particles, and the like generated on the processing surface of the wafer after the ashing processing. In this apparatus, a chemical solution is first supplied to a wafer to perform a chemical cleaning process, and then a rinsing process including particle removal is performed with pure water, and finally the wafer is rotated to remove the pure water so as to be shaken off. A series of cleaning processes are performed in which a drying process gas such as N2 gas is supplied to perform a drying process. A fluid mixing nozzle, which is a kind of nozzle for supplying pure water, discharges pure water by applying high pressure to the pure water by mixing an inert gas such as N2 gas and sprays it on the processing surface of the wafer. To supply.

  By the way, when pure water is supplied to a highly hydrophobic wafer, there is a problem that a watermark is generated after the drying process. Although the watermark is detected as a defect by the surface inspection device, many defects are detected particularly when pure water is supplied by the two-fluid supply nozzle. Therefore, the fluid mixing nozzle may be used for cleaning a hydrophobic wafer. It was difficult. However, in the conventional cleaning process, the processing surface of the wafer may become hydrophobic depending on the type of chemical solution supplied to the wafer during chemical cleaning, which causes defects.

  Accordingly, an object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of processing a hydrophobic wafer using a fluid mixing nozzle.

  In order to solve the above problems, according to the present invention, a processing liquid supply means for supplying a processing liquid, an inert gas supply means for supplying an inert gas, the inert gas is mixed with the processing liquid, A substrate processing apparatus comprising a two-fluid mixing nozzle for discharging a processing liquid pressurized by an inert gas onto a substrate, and processing the substrate with the processing liquid, wherein the processing liquid supply means has a surface of the processing liquid There is provided a substrate processing apparatus comprising fluid mixing means for mixing a fluid for reducing tension and the processing liquid. In this substrate processing apparatus, the fluid is mixed with the processing liquid and supplied to the wafer, and the surface tension of the processing liquid adhering to the wafer is reduced, so that the generation of watermarks can be suppressed.

  It is preferable to provide a control unit for controlling the fluid mixing means. Moreover, you may provide the chemical | medical solution supply nozzle which supplies a chemical | medical solution. Furthermore, it is preferable that the control unit controls the fluid mixing unit based on the type of the chemical solution. In this case, the hydrophobic strength of the wafer after chemical treatment can be predicted from the type of chemical.

  Further, an inspection means for inspecting whether the substrate is hydrophobic or hydrophilic may be provided. Furthermore, it is preferable that the control unit controls the fluid mixing unit based on the inspection result of the inspection unit. That is, the stronger the hydrophobicity of the wafer, the greater the amount of the fluid mixed and the lower the surface tension of the processing liquid. However, when the hydrophobicity is weak, the amount of fluid mixed is decreased and the fluid is mixed. Can save on usage.

  Further, according to the present invention, the treatment liquid and the inert gas are mixed by the two-fluid mixing nozzle, the treatment liquid pressurized by the inert gas is supplied, and the treatment liquid pressurized by the inert gas. A substrate processing method for processing a substrate by: providing a substrate processing method, wherein a processing liquid mixed with a fluid that lowers the surface tension of the processing liquid and the inert gas are mixed and supplied. Is done. In this substrate processing method, the fluid is mixed with the processing liquid and supplied to the wafer, and the surface tension of the processing liquid adhering to the wafer is reduced, so that the generation of watermarks can be suppressed.

  You may make it have the process of supplying a chemical | medical solution and processing a board | substrate before the process of processing a board | substrate with the said process liquid. The mixing of the fluid may be controlled based on the type of the chemical solution.

  A droplet of a test chemical for inspecting the hydrophobic strength of the substrate is dropped on the processing surface of the substrate, and the contact angle of the droplet on the processing surface of the substrate is measured to thereby make the substrate hydrophobic. It may be inspected whether it is hydrophilic or hydrophilic. That is, if the substrate has a strong hydrophobicity, the contact angle of the inspection liquid on the processing surface of the substrate increases, so that it is possible to inspect whether the substrate is hydrophobic or hydrophilic. Furthermore, it is preferable to control mixing of the fluid based on the magnitude of the contact angle. In this case, when the hydrophobicity is weak, it is possible to reduce the amount of fluid used to reduce the surface tension of the treatment liquid and save the amount of fluid used.

  Further, the method may include a step of ashing the substrate, a step of processing the substrate by supplying the chemical solution, a step of drying the substrate, and a step of baking the substrate.

  In the present invention, it is preferable to use pure water as the treatment liquid and use, for example, IPA (isopropyl alcohol) as the fluid for reducing the surface tension of the treatment liquid.

  According to the substrate processing apparatus and the substrate processing method of the present invention, the generation of watermarks can be suppressed by supplying IPA mixed pure water having a surface tension smaller than that of pure water. Therefore, the hydrophobic wafer can be processed using the fluid mixing nozzle. When the wafer is hydrophilic, IPA is not mixed with pure water, so that the amount of IPA used can be saved. In addition, the amount of IPA used can be saved by adjusting the amount of IPA mixed with pure water according to the hydrophobicity of the wafer.

  Hereinafter, a preferred embodiment of the present invention will be described based on a substrate processing apparatus unit configured to clean both surfaces of a wafer as an example of a substrate. FIG. 1 is a schematic plan view of a processing system 1 incorporating substrate processing units 22, 23, 24, and 25 which are substrate processing apparatuses. FIG. 2 is a schematic side view thereof. The processing system 1 includes a loading / unloading unit 2 for loading / unloading the wafer W into / from the cleaning processing unit 3, a cleaning processing unit 3 for performing a cleaning process and a thermal process after the cleaning process, an etching process and / or an etching process for the wafer W. Or it comprises the etching process part 4 which performs an ashing process.

  The loading / unloading unit 2 includes an in / out port 6 provided with a mounting table 10 on which a plurality of, for example, 25 wafers W can be accommodated substantially horizontally at predetermined intervals. , The wafer transfer unit 7 provided with the wafer transfer device 12 for delivering the wafer between the carrier C mounted on the mounting table 10 and the cleaning processing unit 3, and the processing in the etching processing unit 4 and the cleaning processing unit 3 For the wafer W that has been completed, the line width measuring unit 8 that measures the line width of the pattern applied to the processing surface is configured.

  In the carrier C, the wafer W is carried in and out through one side surface of the carrier C, and a lid that can be opened and closed is provided on this side surface. Further, a shelf plate for holding the wafer W at a predetermined interval is provided on the inner wall, and 25 slots for accommodating the wafer W are formed. One wafer W is accommodated in each slot in a state where the front surface (processing surface on which a semiconductor device is formed) is the upper surface (the upper surface when the wafer W is held horizontally).

  On the mounting table 10 of the in / out port 6, for example, three carriers can be arranged in a predetermined position by being arranged in the Y direction on the horizontal plane. The carrier C is placed with the side surface on which the lid is provided facing toward the boundary wall 15 between the in / out port 6 and the wafer transfer unit 7. A window portion 16 is formed in the boundary wall 15 at a position corresponding to the place where the carrier C is placed, and a window portion opening / closing mechanism that opens and closes the window portion 16 by a shutter or the like on the wafer transfer portion 7 side of the window portion 16. 17 is provided.

  The window opening / closing mechanism 17 can also open and close the lid provided on the carrier C, and simultaneously opens and closes the lid of the carrier C. The window opening / closing mechanism 17 is preferably provided with an interlock so that it does not operate when the carrier C is not placed at a predetermined position of the placement table. When the window 16 is opened to allow the wafer loading / unloading port of the carrier C to communicate with the wafer transfer unit 7, the wafer C can be accessed by the wafer transfer device 7 disposed in the wafer transfer unit. It is possible to perform. A wafer detection device (not shown) is provided above the window 16 so that the number and state of the wafers W accommodated in the carrier C can be detected for each slot. Such a wafer detection apparatus can be mounted on the window opening / closing mechanism 17.

  A wafer transfer device 12 disposed in the wafer transfer unit 7 is movable in the Y direction and the Z direction, and is configured to be rotatable in the XY plane (θ direction). The wafer transfer device 7 has take-out and storage arms 19a and 19b for holding two wafers W. The take-out and storage arms 19a and 19b are slidable in the XY plane and are independent of each other. It is possible to move forward and backward. In this way, the wafer transfer device 12 accesses a slot having an arbitrary height for all the carriers C mounted on the mounting table 10, and two wafer transfer units (upper and lower) disposed in the cleaning processing unit 3 ( TRS) The wafers W can be transferred from the in / out port 6 side to the cleaning processing unit 3 side, and conversely from the cleaning processing unit 3 side to the in / out port 6 side by accessing the TRs 20a and 20b. ing. In addition, the wafer transfer device 12 transfers the wafer W that has been processed in the etching processing unit 4 and the cleaning processing unit 3 from the wafer transfer units (TRS) 20a and 20b to the line width measuring unit 8, and the line width measuring unit 8 The wafer W that has been inspected at can be transferred to the in / out port 6 side.

  The cleaning processing unit 3 is provided between the etching processing unit 4 and the wafer transfer units (TRS) 20 a and 20 b for temporarily placing the wafer W to transfer the wafer W to and from the wafer transfer unit 7. Wafer transfer units (TRS) 21a, 21b for temporarily placing the wafer W to transfer the wafer W, four substrate processing units 22, 23, 24, 25 according to the present embodiment, and cleaning The heating / cooling unit 26 includes, for example, five stacked baking units that heat-process the processed wafers W and a cooling unit that cools the heated wafers W. Further, the cleaning processing unit 3 includes a wafer transfer unit 30 provided with a wafer transfer device 31 for transferring a wafer between the etching processing unit 4 and the wafer transfer units 21a and 21b, and a main wafer transfer device 32. Yes. The main wafer transfer device 32 is arranged to be accessible to the wafer transfer units 20a, 20b, 21a, 21b, the substrate processing units 22, 23, 24, 25, the baking unit and the cooling unit of the heating / cooling unit 26.

  Also, the cleaning processing unit 3 performs maintenance of the wafer transfer units 20a, 20b, 21a, 21b, the substrate processing units 22, 23, 24, 25 of the cleaning processing unit 3, and the baking unit and cooling unit of the heating / cooling unit 26. A maintenance area 34 is provided for easy maintenance. A fan filter unit (FFU) 35 for downflowing clean air is disposed on each unit and the main wafer transfer device 32 on the ceiling portion of the cleaning processing unit 3.

  The wafer transfer units 20a and 20b are arranged in two upper and lower stages. For example, the lower wafer transfer unit 20a places a wafer W to be transferred from the in / out port 6 side to the cleaning processing unit 3 side. Therefore, the upper wafer transfer unit 20b can be used to place the wafer W to be transferred from the cleaning processing unit 3 side to the in / out port 6 side.

  The wafer transfer units 21a and 21b are arranged in two upper and lower stages. For example, the lower wafer transfer unit 21a is used to place the wafer W to be transferred from the cleaning processing unit 3 side to the etching processing unit 4. The upper wafer transfer unit 21b can be used to place the wafer W transferred from the etching processing unit 4 to the cleaning processing unit 3 side. An inspection device 36 for inspecting whether the substrate is hydrophobic or hydrophilic is installed above the upper wafer transfer unit 21b.

  The inspection device 36 drops a liquid droplet of an inspection chemical for inspecting the hydrophobicity of the wafer W onto the processing surface of the wafer W, and measures the contact angle φ of the droplet D on the processing surface of the wafer W. be able to. 3A and 3B show the processing surface of the wafer W when the droplet D is dropped. The contact angle φ is an angle formed by the processing surface of the wafer W and the tangent L of the droplet D on the processing surface. When the hydrophobicity of the wafer W is strong, the contact angle φ is large as shown in FIG. 3A, but when the hydrophilicity is strong, the contact angle φ is small as shown in FIG. Therefore, by measuring the contact angle φ of the droplet D on the processing surface of the wafer W, the hydrophobic strength of the wafer W can be measured. The inspection device 36 is connected to the control unit 37 via a signal line 38, and the measured hydrophobic strength is transmitted to the control unit 37 as a detection signal. Therefore, the control unit 37 can determine whether the wafer W is hydrophobic or hydrophilic. When the wafer W is loaded into the substrate processing units 22, 23, 24, 25, the wafer W is placed on the wafer transfer unit 21 a before loading, and the inspection device 36 detects the hydrophobicity of the processing surface. It has become.

  A part of the downflow from the fan filter unit (FFU) 35 flows out toward the wafer transfer unit 7 through the wafer transfer units 20a and 20b and the space above the wafer transfer units 20a and 20b. Thereby, intrusion of particles and the like from the wafer transfer unit 7 to the cleaning processing unit 3 is prevented, and the cleanliness of the cleaning processing unit 2 is maintained. Further, a part of the downflow from the fan filter unit (FFU) 35 flows out toward the wafer transfer unit 31 through the wafer transfer units 21a and 21b and the space above the wafer transfer units 21a and 21b. Thereby, intrusion of particles or the like from the wafer transfer unit 31 to the cleaning processing unit 3 is prevented, and the cleanliness of the cleaning processing unit 3 is maintained.

  A wafer transfer device 31 disposed in the wafer transfer unit 30 is movable in the Y direction and the Z direction, and is configured to be rotatable in the XY plane (θ direction). The wafer transfer device 31 has take-out and storage arms 39a and 39b for holding two wafers W. The take-out and storage arms 39a and 39b are slidable in the X direction, and are independently moved forward and backward. Is possible. In this way, the wafer transfer device 31 accesses the upper and lower two wafer transfer units (TRS) 21a and 21b arranged in the cleaning processing unit 3 and from the etching processing unit 4 side to the cleaning processing unit 3 side. The wafer W can be transferred from the etching processing unit 4 side to the cleaning processing unit 3 side.

  The main wafer transfer device 32 includes a cylindrical support 40 that can be rotated by a rotational driving force of a motor (not shown), and a wafer transfer body 41 that can be moved up and down in the Z direction along the inside of the cylindrical support 40. Have. The wafer transfer body 41 is rotated integrally with the rotation of the cylindrical support 40, and is provided with three transfer arms 42a arranged in multiple stages that can move forward and backward independently. , 42b, 42c.

  The substrate processing units 22, 23, 24, and 25 are arranged in two stages, two in each of the upper and lower stages. As shown in FIG. 1, the substrate processing units 22 and 23 and the substrate processing units 24 and 25 have a symmetric structure with respect to the wall surface 43 forming the boundary, except that they are symmetric. For example, the substrate processing units 22, 23, 24, and 25 have substantially the same configuration. Therefore, the structure of the substrate processing unit 22 will be described in detail below using the substrate processing unit 22 as an example.

  FIG. 4 is a plan view of the substrate processing unit 22. In the unit chamber 45 of the substrate processing unit 22, an outer chamber 46 having a sealed structure for storing the wafer W, a chemical arm storage unit 47, and a rinse arm storage unit 48 are provided. An opening 50 is formed in the unit chamber 45, and a unit chamber mechanical shutter 51 that opens and closes the opening 50 by an opening / closing mechanism (not shown) is provided, and the wafer W is transferred from the opening 50 to the substrate processing unit 22 by the transfer arm 42 a. When carrying in / out, the unit chamber mechanical shutter 51 is opened. The mechanical shutter 51 for the unit chamber opens and closes the opening 50 from the inside of the unit chamber 45. Even when the inside of the unit chamber 45 becomes a positive pressure, the atmosphere inside the unit chamber 45 leaks to the outside. Absent.

  An opening 52 is formed in the outer chamber 46, and an outer chamber mechanical shutter 53 that opens and closes the opening 52 by a cylinder driving mechanism (not shown) is provided. For example, the wafer W is opened from the opening 52 to the outer chamber 46 by the transfer arm 42b. The outer chamber mechanical shutter 53 is opened when the is carried in and out. The outer chamber mechanical shutter 53 opens and closes the opening 52 from the inside of the outer chamber 46, and even when the inside of the outer chamber 46 becomes a positive pressure, the atmosphere inside the outer chamber 46 leaks to the outside. Absent. In addition, an opening 54 is formed in the chemical arm storage 47, and a chemical arm storage shutter 55 that opens and closes the opening 54 by a drive mechanism (not shown) is provided. When the chemical arm storage 47 is isolated from the outer chamber 46, the chemical arm storage shutter 55 is closed. An opening 56 is formed in the rinsing system arm storage 48, and a rinsing system arm shutter 57 for opening and closing the opening 56 by a drive mechanism (not shown) is provided. When isolating the rinse arm storage 48 from the outer chamber 46, the rinse arm storage shutter 57 is closed.

  In the chemical liquid arm storage section 47, a chemical liquid arm 60 capable of discharging a chemical liquid for cleaning the wafer W is stored. The chemical solution arm 60 can scan at least the center to the peripheral edge of the wafer W held by a spin chuck 71 described later in the outer chamber 46. The chemical system arm 60 is retracted in the chemical system arm storage section 47 except during processing. Further, the chemical liquid arm storage unit 47 is provided with an arm cleaning device (not shown), and the chemical liquid arm 60 can be cleaned when the chemical liquid arm 60 is waiting in the chemical liquid arm storage unit 47. .

  In the rinse arm storage section 48, a rinse arm 63 capable of discharging pure water as a treatment liquid to be rinsed and N2 gas as an inert gas is stored. The rinse arm 63 is accommodated in the outer chamber 46 and can scan at least the center to the peripheral edge of the wafer W held by a spin chuck 71 described later. The rinse arm 63 is retracted in the rinse arm storage section 48 except during processing. A two-fluid mixing nozzle 65 that mixes N2 gas with pure water (DIW) and discharges it to the wafer W is provided at the tip of the rinse arm 63. The two-fluid mixing nozzle 65 mixes N2 gas with pure water, thereby giving high pressure to the pure water that is a rinsing liquid and discharging it so as to spray it onto the processing surface of the wafer W. When the wafer W has hydrophobicity, the two-fluid mixing nozzle 65 discharges IPA mixed pure water described later as a rinsing liquid instead of pure water.

  Further, the rinsing arm 63 has pure water supply means 66 for supplying pure water (DIW) discharged from the two-fluid mixing nozzle 65 and N2 gas supply means 67 for supplying N2 gas. The pure water supply means 66 and the N2 gas supply means 67 are provided so as to penetrate through the inside of the rinse arm 63 and supply pure water and N2 gas to the two-fluid mixing nozzle 65. In addition, the rinse arm storage unit 48 is provided with an arm cleaning device (not shown), and the rinse arm 63 can be cleaned when the rinse arm 63 is waiting in the rinse arm storage unit 48. .

  As shown in FIG. 5, in the outer chamber 46, an inner cup 70 for storing the wafer W, and the wafer W can be rotated in the inner cup 70, for example, with the front surface (processing surface) of the wafer W as the upper surface. A spin chuck 71 is provided. In the outer chamber 46, an inclined portion is formed at a height where the wafer W supported by the spin chuck 71 is located, and the wafer W is surrounded by the inclined portion. The upper portion of the outer chamber mechanical shutter 53 is a part of the inclined portion. When the wafer W is transferred to the spin chuck 71, the outer chamber mechanical shutter 53 is opened and the wafer W is moved horizontally.

  The spin chuck 71 includes a chuck body 75 as a support member that supports a holding member 80 that holds the wafer W, and a rotating cylinder 76 connected to the bottom of the chuck body 75. A support pin (not shown) for supporting the peripheral edge of the back surface of the wafer W and a holding member 80 for holding the wafer W from the peripheral edge are mounted on the chuck body 75 at a plurality of locations. In the illustrated example, holding members 80 are arranged at three locations around the chuck main body 75 so that the central angle is 120 °, and the wafer W can be held from around by the three holding members 80. It has become. Further, three support pins are provided on the chuck body 75 so that the peripheral edge of the wafer W can be similarly supported from the lower surface side at a position where the central angle is 120 °.

  A belt 81 is wound around the outer peripheral surface of the rotating cylinder 76, and the entire spin chuck 71 is rotated by rotating the belt 81 by a motor 82. Each holding member 80 is configured to hold the peripheral edge portion of the wafer W from the outside as shown in FIG. 4 using a centrifugal force when the spin chuck 71 rotates. When the spin chuck 71 is stationary, the back surface of the wafer W is supported by the support pins, and when the spin chuck 71 is rotating, the peripheral portion of the wafer W is held by the holding member 80.

  The inner cup 70 is lowered to the position shown in FIG. 7 so that the spin chuck 71 protrudes above the upper end of the inner cup 70 to transfer the wafer W, and is raised to surround the spin chuck 71 and the wafer W. In addition, the cleaning liquid or the like supplied to both surfaces of the wafer W can be moved up and down in a state that prevents the cleaning liquid from scattering around. An inner cup discharge pipe (not shown) for discharging the liquid droplets in the inner cup 70 is connected to the bottom of the inner cup 70. An outer chamber discharge pipe (not shown) for discharging the liquid droplets in the outer chamber 46 is connected to the bottom of the outer chamber 46.

  When the inner cup 70 is lowered, as shown in FIG. 7, the spin chuck 71 and the wafer W held by the spin chuck 71 are in a state of protruding upward from the upper end of the inner cup 70. In this case, the droplet in the outer chamber 46 descends outside the inner cup 70 and is drained by the outer chamber discharge pipe. On the other hand, when the inner cup 70 is raised, the inner cup 70 surrounds the spin chuck 71 and the wafer W, and the cleaning liquid or the like supplied to both surfaces of the wafer W is prevented from scattering around. In this case, the upper part of the inner cup 70 is close to the inner wall of the outer chamber 46, and the droplets in the inner cup 70 are drained by the inner cup discharge pipe.

  FIG. 6 shows a supply circuit of pure water (DIW) and N2 gas. At the tip of the two-fluid mixing nozzle 65, a discharge port 90 for discharging pure water supplied from the pure water supply means 66 is provided. The pure water supply means 66 includes a pure water supply source 92 and an open / close valve 93. Pure water discharged from the discharge port 90 is fed from a pure water supply source 92 provided in the pure water supply means 66. The pure water supply means 66 is provided through the two-fluid mixing nozzle 65 and is connected to the discharge port 90. Further, inside the two-fluid mixing nozzle 65, an N2 gas supply means 67 is interposed in the middle of the pure water supply means 66. The on-off valve 93 is wired to the control unit 37 via a signal line 94. The control unit 37 controls the opening and closing by transmitting a control signal to the on-off valve 93.

  The N2 gas supply means 67 includes an N2 gas supply source 95, a first supply circuit 97a for sending N2 gas from the N2 gas supply source 95, N2 gas sent from the N2 gas supply source 95 and IPA (isopropyl alcohol). A second supply circuit 97b to be mixed, a switching on / off valve 98 that switches the first supply circuit 97a and the second supply circuit 97b to connect to the supply circuit 99, and N2 gas that has passed through the switching on / off valve 98 is supplied with pure water. A supply circuit 99 is provided.

  The first supply circuit 97a connects an N2 gas supply source 95 and a switching on / off valve 98, and a pipe 100 is interposed in the middle of the first supply circuit 97a. The second supply circuit 97b includes a pipe 100 that branches from the middle of the first supply circuit 97a, an IPA tank 105 that stores IPA (isopropyl alcohol) that is a fluid that reduces the surface tension of pure water (DIW), and an IPA tank. 105 and a pipe 106 that connects the switching valve 98. The pipe 100 is connected to the IPA tank 105 and sends N 2 gas into the IPA tank 105 from the first supply circuit 97a. The downstream end of the pipe 100 is immersed in IPA stored in the IPA tank 105. Therefore, the N 2 gas that has passed through the pipe 100 is bubbled by the IPA stored in the IPA tank 105. The N2 gas bubbled by the IPA becomes a mixed gas that mixes the IPA atmosphere. The IPA tank 105 is a sealed container, and an IPA mixed N2 gas, which is an N2 gas mixed with an IPA atmosphere, is stored in the upper part of the IPA stored in the lower part. The pipe 106 is connected to the upper part of the IPA tank 105, and sends out the IPA mixed N 2 gas stored in the upper part of the IPA tank 105 from the IPA tank 105 to the switching on-off valve 98. As described above, the second supply circuit 97b is configured to send the N2 gas as IPA mixed N2 gas by bubbling the N2 gas to the IPA. That is, the second supply circuit 97b is an IPA mixing means for mixing IPA with N2 gas.

  The N 2 gas or the IPA mixed N 2 gas that has passed through the switching on-off valve 98 passes through the supply circuit 99 and is sent to the pure water supply means 66. Here, N2 gas or IPA mixed N2 gas and pure water are mixed, and the pure water is pressurized by N2 gas or IPA mixed N2 gas. Accordingly, it is possible to supply the wafer W so as to spray pure water. When the IPA mixed N2 gas is mixed with pure water, IPA is mixed into the pure water discharged onto the wafer W, resulting in IPA mixed pure water having a surface tension smaller than that of the pure water.

  If the wafer W is highly hydrophobic, if pure water adheres to the processing surface of the wafer W, the contact angle φ increases as shown in FIG. When it dries, the water mark is likely to occur. However, even if the hydrophobicity of the wafer W is strong, if the IPA mixed pure water having a surface tension smaller than that of pure water adheres to the processing surface of the wafer W, the contact angle φ becomes small due to the small surface tension. When the IPA mixed pure water droplets evaporate and the wafer W is dried, it is possible to make it difficult to generate a watermark. Thus, the surface tension of pure water adhering to the wafer can be reduced, and the generation of watermarks can be suppressed. On the other hand, when the hydrophilicity of the wafer W is strong, if pure water adheres to the processing surface of the wafer W, the contact angle φ decreases as shown in FIG. 3B, and the pure water droplet WD evaporates. When the wafer W is dried, it becomes difficult to generate a watermark. Therefore, it is not necessary to mix IPA into the pure water discharged onto the wafer W.

  The switching on / off valve 98 is wired to the control unit 37 via the signal line 102. The control unit 37 transmits a control signal to the switching on / off valve 98 to switch between a state in which the first supply circuit 97a and the supply circuit 99 are connected and a state in which the second supply circuit 97b and the supply circuit 99 are connected. Can do. Further, the control unit 37 switches the switching on / off valve 98 based on the inspection result received from the inspection device 36. That is, when the wafer W carried into the substrate processing unit 22 is hydrophilic, the wafer is switched to the first supply circuit 97a that sends out N2 gas, and when it is hydrophobic, the second supply circuit that sends out IPA mixed N2 gas. A control signal is transmitted to the switching on-off valve 98 so as to switch to 97b. Therefore, the two-fluid mixing nozzle 65 discharges a mixed fluid of pure water and N2 gas to the hydrophilic wafer W, and discharges a mixed fluid of pure water, N2 gas and IPA to the hydrophobic wafer W. It is designed to discharge. The hydrophilic wafer W is rinsed with pure water, and the hydrophobic wafer W is rinsed with IPA mixed pure water. In this case, since the IPA is not mixed when the hydrophobicity of the wafer W is weak, the amount of IPA used can be saved.

  The above is the configuration of the substrate processing unit 22, but the other substrate processing units 23, 24, and 25 provided in the processing system 1 have the same configuration as the substrate processing unit 22, and the wafer W is made of a chemical solution and pure water. Can be washed.

  The etching processing unit 4 that performs etching processing and / or ashing processing on the wafer W includes a left etching processing unit 110 a provided on the left side when viewed from the wafer transfer unit 30 and a right etching processing unit 110 b provided on the right side. . The left etching processing unit 110a includes an etching processing device 120a that performs etching processing and / or ashing processing, and a load lock 122a that is a loading / unloading unit that loads and unloads the wafer W into / from the etching processing device 120a. The load lock 122 a delivers a wafer between the etching processing apparatus 120 a and the wafer transfer unit 30. The load lock 122a is provided with wafer transfer arms 123a and 124a for holding two wafers W. The right etching processing unit 110b has the same configuration as that of the left etching processing unit 110a, and can perform etching processing and / or ashing processing on the wafer W. That is, an etching processing apparatus 120b, a load lock 122b, and wafer transfer arms 123b and 124b are provided.

  Next, processing steps for the wafer W in the processing system 1 configured as described above will be described. First, a carrier C storing, for example, 25 wafers W not yet etched by a transfer robot (not shown) is placed on the in / out port 6. Then, the wafers W are taken out one by one from the carrier C placed on the in / out port 6 by, for example, the lower take-out and storage arm 19a of the wafer transfer device 12. The take-out storage arm 19a places the wafer W on the lower wafer transfer unit 20a. Next, the main wafer transfer device 32 receives the wafer W placed on the wafer transfer unit 20a by, for example, the lowermost transfer arm 42a, and the cylindrical support 40 rotates in the θ direction, thereby receiving the received wafer W. Is transferred to the wafer transfer units 21a and 21b. Then, the wafer W is placed on the lower wafer transfer unit 21a by the transfer arm 42a. Subsequently, the wafer transfer device 31 receives, for example, the wafer W placed on the wafer transfer unit 21a by the lower take-out storage arm 39a and transfers it to the left etching processing unit 110a or the right etching processing unit 110b.

  For example, the wafer W transferred to the left etching processing unit 110a is carried into the etching processing apparatus 120a by, for example, the lower wafer transfer arm 123a provided in the load lock 122a. In the etching processing apparatus 120a, the ashing process is performed after the etching process. Thereafter, the wafer is transported from the etching processing apparatus 120a by, for example, the wafer transport arm 124a, held by, for example, the upper take-out storage arm 39b, transported by the wafer transport apparatus 31, and placed on the upper wafer transfer unit 21b.

  In the upper wafer transfer unit 21b, the inspection device 36 performs the hydrophobicity inspection of the wafer W. First, a droplet D of a chemical solution for inspection for inspecting the strength of hydrophobicity is dropped on the processing surface of the wafer W after being subjected to the etching process and / or the ashing process placed on the wafer delivery unit 21b. To do. Then, the contact angle φ formed by the droplet D is measured, the hydrophobic strength is detected from the measured contact angle φ, and a detection signal is transmitted to the control unit 37.

  On the other hand, the wafer W whose contact angle φ has been measured on the processing surface is held by, for example, the transfer arm 42b of the main wafer transfer device 32, and appropriately transferred from the wafer transfer unit 21b to each substrate processing unit 22, 23, 24, 25. Is done. Then, by performing predetermined cleaning processing including chemical cleaning, rinsing processing including particle removal cleaning using the two-fluid mixing nozzle 65, and drying processing, contaminants such as polymers and particles adhering to the wafer W are removed. Removed. Here, based on the hydrophobicity detected in the wafer delivery unit 21b, the control unit 37 transmits a control signal to the switching on / off valve 98, and the mixed fluid discharged from the two-fluid mixing nozzle 65 is switched. The wafer W that has been subjected to the predetermined cleaning process is appropriately unloaded from each of the substrate processing units 22, 23, 24, 25 by, for example, the transfer arm 42 c of the main wafer transfer apparatus 32.

  The wafer W carried out from each substrate processing unit 22, 23, 24, 25 is transferred to the wafer delivery unit 21a, 21b side by the rotation of the cylindrical support 40 of the main wafer transfer device 32, and is heated and transferred by the transfer arm 42c. It is appropriately carried into any of the five baking units installed in the cooling unit 26. The wafers W that have been baked in each baking unit are appropriately unloaded from each baking unit, for example, by the transfer arm 42c of the main wafer transfer device 32, and transferred to the wafer transfer units 21a and 21b by the rotation of the cylindrical support 40. The upper transfer arm 42c places the wafer on the upper wafer transfer unit 21b.

  As described above, the ashing process is performed after the etching process of the wafer W in the etching unit 4, and then the chemical processing and the rinsing process are performed in the substrate processing units 22, 23, 24, and 25 of the cleaning unit 3. Then, a drying process for drying the wafer W is performed, and a baking process is performed in each baking unit.

  Subsequently, the wafer transfer device 12 receives the wafer W from the upper wafer transfer unit 21b by, for example, the upper take-out storage arm 19b and transfers it to the line width measuring unit 8. The line width measuring unit 8 measures the line width of the pattern applied to the processing surface of the wafer that has been processed in the etching processing unit 4 and the cleaning processing unit 3. Thereafter, the wafer W is unloaded from the line width measuring unit 8 by the wafer transfer device 12 and transferred to the in / out port 6 side, and stored in the carrier C again.

  Here, the cleaning in the substrate processing unit 22 will be described as a representative. As shown in FIG. 5, first, the unit chamber mechanical shutter 51 of the substrate processing unit 22 is opened, and the outer chamber mechanical shutter 53 of the outer chamber 46 is opened. Then, the transfer arm 42 b holding the wafer W is moved into the substrate processing unit 22. The inner cup 70 is lowered in advance to cause the chuck body 75 to relatively protrude upward. Also, the chemical solution arm storage shutter 55 and the rinse arm storage shutter 57 are closed.

  The main wafer transfer device 32 moves the transfer arm 42b horizontally to deliver the wafer W to the spin chuck 71. The spin chuck 71 moves the surface (processing surface) of the wafer W on which the semiconductor device is formed by support pins (not shown). The wafer W is supported on the upper surface. After the wafer W is transferred to the spin chuck 71, the transfer arm 42b is withdrawn from the inside of the outer chamber 46 and the unit chamber mechanical shutter 51, and after the withdrawal, the unit chamber mechanical shutter 51 and the outer chamber 46 of the substrate processing unit 22 are removed. The outer chamber mechanical shutter 53 is closed. Further, the inner cup 70 rises and surrounds the chuck body 75 and the wafer W.

  Next, the spin chuck 71 starts to rotate and holds the wafer W in rotation. In addition, the chemical arm storage shutter 55 is opened, and the chemical arm 60 is rotated above the wafer W. The chemical solution arm 60 scans at least the center to the peripheral portion of the wafer W rotated and held by the spin chuck 71 and supplies the chemical solution. In this way, the chemical solution can be diffused over the entire surface of the wafer W. The supplied chemical solution is adjusted to a predetermined temperature by a temperature controller such as a heater. The chemical liquid that flows to the periphery of the wafer W flows into the inner cup 70 and is discharged from the outer chamber 46 through an inner cup discharge pipe (not shown). When the cleaning with the chemical liquid is completed, the chemical liquid arm 60 moves into the chemical liquid arm storage section 47, and the chemical liquid arm storage section shutter 55 is closed. The chemical liquid arm storage section shutter 55 is kept closed while the chemical liquid arm storage section 47 is kept closed, and the chemical liquid atmosphere generated from the chemical liquid arm 60 is prevented from contaminating the wafer W and the rinse arm 63. Thereafter, the inner cup 70 is lowered as shown in FIG. 7, and the chuck body 75 and the wafer W are surrounded by the outer chamber 46.

  Next, the rinse arm storage portion shutter 57 is opened, and the rinse arm 63 is moved from the rinse arm storage portion 48 into the outer chamber 46 and is rotated above the wafer W. The control unit 37 transmits a control signal, opens the on-off valve 93 of the pure water supply means 66 shown in FIG. 6, and sends pure water to the two-fluid mixing nozzle 65. On the other hand, the control unit 37 determines whether the wafer W is hydrophobic or hydrophilic from the result of inspection by the inspection device 36 before the wafer W is carried into the substrate processing unit 22. Then, a control signal based on this determination is transmitted to the switching valve 98 via the signal line 102. That is, by controlling the switching of the switching valve 98, the two-fluid mixing nozzle 65 discharges a mixed fluid in which pure water and N2 gas are mixed when the wafer W is hydrophilic, and the wafer W becomes hydrophobic. If it is, the mixed fluid in which pure water, N2 gas and IPA are mixed is discharged.

  When the wafer W is hydrophilic, the switching on / off valve 98 is switched to the first supply circuit 97a, N2 gas is sent from the N2 gas supply source 95, and supplied to the two-fluid mixing nozzle 65. The N 2 gas passes through the supply circuit 99 and flows into the pure water supply means 66 at an intervening portion between the supply circuit 99 and the pure water supply means 66. Here, pure water is pressurized by N2 gas. Then, N2 gas and pressurized pure water are discharged from the discharge port 90, and the pure water is supplied to the hydrophilic wafer W for rinsing treatment.

  On the other hand, when the wafer W is hydrophobic, the switching on / off valve 98 is switched to the second supply circuit 97b, the IPA mixed N2 gas stored in the upper part of the IPA tank 105 is sent out, and supplied to the two-fluid mixing nozzle 65. To do. The IPA mixed N 2 gas passes through the supply circuit 99 and flows into the pure water supply means 66 at an intervening portion between the supply circuit 99 and the pure water supply means 66. Here, the pure water is pressurized by the IPA mixed N2 gas and becomes IPA mixed pure water when IPA of the IPA mixed N2 gas is mixed. In this way, the IPA mixed N2 gas and the pressurized IPA mixed pure water are discharged from the discharge port 90, and the IPA mixed pure water is supplied to the hydrophobic wafer W to perform the rinsing process.

  The rinse arm 63 scans at least from the center to the periphery of the wafer W, and discharges pure water, a mixed fluid of N2 gas and IPA, or a mixed fluid of pure water and N2 gas from the two-fluid mixing nozzle 65. As shown in FIG. 7, the mixed fluid that flows around the wafer W flows into the outer chamber 46 and is discharged from the outer chamber 46 by an outer chamber discharge pipe (not shown). When the rinsing process with pure water or IPA mixed pure water is completed, the on-off valve 93 and the switching on-off valve 98 are closed, the supply of the mixed fluid is stopped, and the rinsing system arm 63 is moved into the rinsing system arm storage section 48 to rinse. The system arm storage unit shutter 57 is closed.

  After the rinsing process, the wafer W is spin-dried by rotating at a higher speed (for example, about 1500 rpm) than when rinsing the wafer W. In this case, N2 may be supplied to the upper surface of the wafer W by the rinse arm 63. The droplets of pure water or IPA mixed pure water adhering to the wafer W are spun off from the wafer W by centrifugal force and discharged into the outer chamber 46, and further discharged from the outer chamber 46 by an outer chamber discharge pipe (not shown). Is done.

  After the drying process, the wafer W is unloaded from the substrate processing unit 22. The unit chamber mechanical shutter 53 and the outer chamber mechanical shutter 51 are opened, and the wafer transfer device 32 supports, for example, the transfer arm 42b into the device to support the lower surface of the wafer W. Next, the transfer arm 42 b receives the wafer W away from the support pins of the spin chuck 71 and moves out of the substrate processing unit 22.

  According to such a substrate processing unit 22, IPA mixed pure water having a surface tension smaller than that of pure water is supplied to the wafer W by mixing IPA for reducing the surface tension of pure water into the pure water. Occurrence can be suppressed. When the wafer W is hydrophilic, IPA is not mixed with pure water, so that the amount of IPA used can be saved.

  As described above, the present invention is not limited to the above, and can be modified as appropriate. For example, the substrate of the present invention is not limited to a semiconductor wafer, but may be other LCD substrate glass, a CD substrate, a printed substrate, a ceramic substrate, or the like.

  In addition, the present invention is not limited to a substrate processing apparatus to which a chemical solution is supplied, and other processing other than cleaning is performed on the substrate using various other processing liquids, and then rinse treatment with pure water is performed. You may perform the rinse process which removes a particle. For example, when only the etching process is performed in the etching processing unit 4, the substrate processing unit 22 performs the resist removal process with the chemical liquid for resist removal process, and then performs the cleaning process with the chemical liquid and the rinsing liquid described in the embodiment. You may do it. Further, the substrate processing apparatus may scrub the wafer W with a scrubber such as a brush or a sponge. Further, the substrate may be processed only by cleaning the wafer W by the two-fluid mixing nozzle 65, for example, cleaning for removing particles adhering to the wafer W.

  The inspection device 36 may be installed above the outer chamber 46 in the substrate processing unit 22. In this case, an inspection process for inspecting the hydrophobicity of the wafer W can be performed after the chemical treatment process and before the rinsing process. In other words, even when the hydrophobicity of the wafer W varies depending on the type of chemical solution, the hydrophobicity of the wafer W can be inspected without unloading the wafer W from the substrate processing unit 22. For example, when the wafer W is chemically treated with HF (dilute hydrofluoric acid), the wafer W becomes hydrophobic, and when the wafer W is chemically treated with APM (mixed solution of ammonia and hydrogen peroxide solution) or SPM (mixed solution of concentrated sulfuric acid and hydrogen peroxide solution). Shows hydrophilicity. Even in such a case, the rinse liquid supplied to the wafer W can be switched between pure water and IPA mixed pure water according to the inspection result.

  The means for determining the hydrophobicity of the wafer W is not limited to that by the inspection device 36 that measures the contact angle φ, and various other methods can be used. For example, when the type of film formed on the processing surface of the wafer W is confirmed in advance, the rinsing liquid may be switched depending on the type of film. For example, since the polysilicon film is hydrophobic, it is treated with IPA mixed pure water. On the other hand, since the silicon oxide film is hydrophilic, it may be treated with pure water. Moreover, you may make it control mixing of IPA based on the kind of chemical | medical solution used in the chemical | medical solution processing process before a rinse process. For example, when the wafer W is chemically treated with the above-described HF, the processing surface of the wafer W becomes hydrophobic, and is rinsed with IPA mixed pure water. When chemical processing is performed by the above-described APM or SPM, the processing surface of the wafer W becomes hydrophilic, so that the rinsing processing is switched to pure water.

  In FIG. 6, the switching on / off valve 98 is a mixing valve (mixing valve) so that the N2 gas sent from the first supply circuit 97a and the IPA mixed N2 gas sent from the second supply circuit 97b can be mixed. Also good. In this case, based on the inspection result of the inspection device 36, the mixing of the IPA can be controlled by the mixing valve. That is, as the measured contact angle φ is larger and the hydrophobicity is stronger, the amount of IPA mixed with pure water is increased by controlling the amount of IPA mixed N2 gas delivered from the second supply circuit 97b to be increased. The surface tension of mixed pure water can be reduced. Conversely, when the contact angle φ is small and the hydrophobicity is weak, the amount of IPA used can be reduced and the amount of IPA used can be saved. For example, when bubbling N2 gas to IPA, the amount of IPA mixed with N2 gas may be controlled by controlling the speed of N2 gas sent from the pipe 100 to the IPA tank 105. Furthermore, when a temperature control function for adjusting the temperature of the N2 gas is provided and a mixed fluid of pure water and N2 gas is supplied, the temperature of the N2 gas may be supplied at, for example, 50 to 200 ° C. In this case, the drying rate of pure water adhering to the wafer W can be improved, so that the generation of watermarks is more effectively suppressed.

  As shown in FIG. 8, an IPA mixing unit 120 that mixes IPA with pure water may be provided in the pure water supply unit 66. In FIG. 8, IPA mixing means 120 is interposed via a switching mixing valve 121 in the middle of the pure water supply means 66. The IPA supply means 120 includes an IPA supply tank 122 which is an IPA supply source. The switching mixing valve 121 is wired to the control unit 37 via a signal line (not shown). That is, the IPA supply unit 120 and the switching mixing valve 121 are IPA mixing units that mix IPA with pure water. In the middle of the N2 gas supply means 67 provided with the N2 gas supply source 95, an opening / closing valve 125 connected to the control unit 37 via a signal line is provided. Also in this case, pure water, IPA and N 2 gas can be mixed inside the two-fluid mixing nozzle 65.

  In FIG. 8, the switching mixing valve 121 that mixes IPA with pure water may be an adjustment device that can adjust the concentration of IPA of IPA mixed pure water. In this case, mixing of IPA can be controlled based on the inspection result of the inspection device 36. That is, as the measured contact angle φ is larger and the hydrophobicity is stronger, the amount of IPA mixed is increased and the surface tension of IPA mixed pure water is decreased. When the hydrophobicity of the wafer W is very strong, IPA is supplied as it is to the two-fluid mixing nozzle 65 without mixing pure water, and the IPA and N2 gas are mixed and discharged to rinse the wafer W. You may carry out by IPA.

It is a schematic plan view of a processing system. It is a schematic sectional side view of a processing system. It is explanatory drawing explaining the contact angle of the droplet in the processing surface of a wafer. It is a top view of a substrate processing unit. It is a sectional side view of a substrate processing unit. It is explanatory drawing of the supply circuit which supplies a pure water and N2 gas. It is a sectional side view in the outer chamber in a rinse process. It is explanatory drawing of the supply circuit which supplies the pure water and N2 gas concerning the Example of this invention.

Explanation of symbols

C carrier W wafer WD droplet φ contact angle 1 processing system 2 carry-in / out unit 3 cleaning processing unit 4 etching processing unit 20a, 20b wafer transfer unit 21a, 21b wafer transfer unit 22 substrate processing unit 32 main wafer transfer device 36 inspection device 37 Control unit 45 Unit chamber 46 Outer chamber 60 Chemical liquid arm 63 Rinse arm 65 Two-fluid mixing nozzle 66 Pure water supply means 67 N2 gas supply means 70 Inner cup 90 Discharge port 95 N2 gas supply source 97a First supply circuit 97b Second Supply circuit 99 Supply circuit 105 IPA tank

Claims (12)

A treatment liquid supply means for supplying a treatment liquid; an inert gas supply means for supplying an inert gas; and the treatment liquid mixed with the inert gas and pressure applied by the inert gas to the substrate. A substrate processing apparatus comprising a two-fluid mixing nozzle for discharging and processing a substrate with the processing liquid,
A substrate processing apparatus, wherein the processing liquid supply means includes a fluid mixing means for mixing the processing liquid with a fluid that lowers the surface tension of the processing liquid. The substrate processing apparatus according to claim 1, further comprising a control unit that controls the fluid mixing unit. The substrate processing apparatus according to claim 2, further comprising a chemical solution supply nozzle for supplying a chemical solution to the substrate. The substrate processing apparatus according to claim 3, wherein the control unit controls the fluid mixing unit based on a type of the chemical solution. 5. The substrate processing apparatus according to claim 2, further comprising inspection means for inspecting whether the substrate is hydrophobic or hydrophilic. The substrate processing apparatus according to claim 5, wherein the control unit controls the fluid mixing unit based on an inspection result of the inspection unit. A substrate processing method in which a processing liquid and an inert gas are mixed by a two-fluid mixing nozzle, a processing liquid pressurized by an inert gas is supplied, and the substrate is processed by the processing liquid pressurized by the inert gas Because
A substrate processing method, wherein a processing liquid mixed with a fluid that lowers the surface tension of the processing liquid and the inert gas are mixed and supplied. 8. The substrate processing method according to claim 7, further comprising a step of processing the substrate by supplying a chemical solution before the step of processing the substrate with the processing liquid. The substrate processing method according to claim 8, wherein mixing of the fluid is controlled based on a type of the chemical solution. A droplet of an inspection liquid for inspecting the hydrophobic strength of the substrate is dropped on the processing surface of the substrate, and the contact angle of the droplet on the processing surface of the substrate is measured to thereby make the substrate hydrophobic. The substrate processing method according to claim 7, wherein the substrate processing method is inspected for property or hydrophilicity. The substrate processing method according to claim 10, wherein mixing of the fluid is controlled based on the magnitude of the contact angle. Ashing the substrate;
Supplying the processing liquid to process the substrate;
Drying the substrate;
The substrate processing method according to claim 7, further comprising a step of baking the substrate.

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