JP2013030709A - Processing liquid supply device, processing liquid supply method, program, and computer storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently remove fine nano-order particles included in a processing liquid.SOLUTION: A developer supply device 190 which supplies a developer to a developer nozzle 142 comprises: a developer storage tank 201; an intermediate storage tank 203 provided between the developer storage tank 201 and a developer nozzle 142; an electrode 204 which applies dc voltage to the developer; a power supply unit 205 which can freely invert polarities and applies the dc voltage to the electrode 204; a cleaning liquid supply pipe 210 which supplies a cleaning liquid to the intermediate storage tank 203; and a waste liquid pipe 220 which discharges the cleaning liquid from the intermediate storage tank 203. The electrode 204 is provided in the intermediate storage tank 203.

Description

  The present invention relates to a processing liquid supply apparatus, a processing liquid supply method, a program, and a computer storage medium for supplying a processing liquid such as a developer or pure water to a substrate.

  For example, in a photolithography process in a semiconductor device manufacturing process, a resist coating process for coating a resist solution on a wafer to form a resist film, an exposure process for exposing the resist film to a predetermined pattern, and developing the exposed resist film A series of processing such as development processing is sequentially performed to form a predetermined resist pattern on the wafer. These series of processes are performed by a coating and developing system that is a substrate processing system equipped with various processing units for processing a wafer, a transfer mechanism for transferring a wafer, and the like.

  A coating processing apparatus for performing a coating process by supplying a processing liquid such as a developing solution, pure water, or thinner used for the above-described photolithography process to a wafer includes a processing liquid supply apparatus 300 as shown in FIG. Yes. The processing liquid supply apparatus 300 controls, for example, a supply pump 304 that supplies the processing liquid stored in the processing liquid storage tank 301 to the coating nozzle 303 of the coating processing apparatus via the processing liquid supply pipe 302, and supply and stop of the processing liquid. A valve 305 is provided. The processing liquid supply pipe 302 is provided with a filter 306 for filtering the processing liquid, and fine foreign matters (particles) floating in the processing liquid are removed (Patent Document 1).

JP-A-10-305256

  By the way, with the recent miniaturization of semiconductor devices, it has become necessary to control minute defects on the nano order. For this reason, it is required to remove fine particles of about several tens of nanometers, which have not been a problem in the past, from the treatment liquid. This is because if the processing liquid is supplied onto the wafer without removing the fine particles, the fine particles remain on the wafer, resulting in a wafer defect.

  However, with a conventional filter, it is difficult to completely remove the fine particles of about several tens of nanometers. In this case, it can be considered to reduce the number of meshes of the filter, but manufacturing a filter with a small number of meshes requires an advanced processing technique, resulting in an increase in cost.

  Further, when the number of meshes of the filter is reduced, the differential pressure of the filter is increased and clogging is likely to occur, so that there is a problem that frequent filter maintenance is required.

  This invention is made | formed in view of this point, and it aims at removing the nano-sized minute particle contained in a process liquid efficiently.

To achieve the above object, the present invention provides a processing liquid supply apparatus for supplying a processing liquid from a processing liquid supply source to a supply nozzle for supplying a processing liquid to a substrate through a processing liquid supply pipe. An intermediate storage tank that is provided between the processing liquid supply source and the supply nozzle in the liquid supply pipe and temporarily stores the processing liquid supplied from the processing liquid supply source;
The intermediate storage tank includes an electrode that applies a DC voltage to the processing liquid stored in the intermediate storage tank, a power supply unit that applies a DC voltage to the electrode so that the polarity can be reversed, and a cleaning liquid that is supplied to the intermediate storage tank. A cleaning liquid supply pipe to be supplied and a waste liquid pipe for discharging the cleaning liquid from the intermediate storage tank are provided.

  In general, particles in the treatment liquid are charged with either positive or negative charge. And according to this invention, since the electrode is provided in the intermediate | middle storage tank, by applying a DC voltage to the said electrode, the fine particle in the process liquid which was difficult to remove with the conventional filter is removed. It can be collected by the electrode. In addition, there is a cleaning liquid supply pipe for supplying the cleaning liquid from the cleaning liquid supply source to the intermediate storage tank, and a waste liquid pipe for discharging the cleaning liquid from the intermediate storage tank. When the cleaning liquid is supplied to the storage tank, the polarity of the DC voltage applied to the electrode is reversed to release the particles collected on the electrode, and then the cleaning liquid is collected from the waste liquid tube to be collected by the electrode. Particles can be quickly discharged out of the intermediate storage tank. For this reason, the inside of the intermediate storage tank can be kept clean. Therefore, according to the present invention, minute particles in the processing liquid that were difficult to remove with a conventional filter are removed, and maintenance work is also easy because replacement work due to clogging does not occur unlike conventional filters. Therefore, efficient particle removal is possible.

  The intermediate storage tank may be provided with a stirring mechanism for relatively moving the processing liquid stored in the intermediate storage tank and the electrode.

  The electrode may be formed in a mesh shape.

  Either one of the positive electrode and the negative electrode of the electrode is formed in a mesh plate shape parallel to the bottom surface of the intermediate storage tank, and is provided inside the intermediate storage tank, and the other electrode is outside the intermediate storage tank. The agitation mechanism may be an elevating mechanism that elevates and lowers one of the poles provided inside the intermediate storage tank in the vertical direction.

  Either one of the positive electrode and the negative electrode of the electrode is formed in a mesh plate shape, and is provided along the rotation axis provided in the vertical direction inside the intermediate storage tank, and the other electrode is The stirring mechanism provided outside the intermediate storage tank may be a rotating mechanism that rotates the rotating shaft.

The electrode is formed in a mesh plate shape parallel to the bottom surface of the intermediate storage tank,
A plurality of positive electrodes and negative electrodes of the electrodes may be alternately arranged inside the intermediate storage tank along the height direction of the intermediate storage tank.

  A plurality of the intermediate storage tanks may be arranged in parallel in the processing liquid supply pipe.

  According to another aspect of the present invention, there is provided a processing liquid supply method for supplying a processing liquid from a processing liquid supply source to a supply nozzle for supplying a processing liquid to a substrate through a processing liquid supply pipe, from the processing liquid supply source. The supplied processing liquid is temporarily stored in an intermediate storage tank provided between the processing liquid supply source and the supply nozzle in the processing liquid supply pipe, and then, via an electrode provided in the intermediate storage tank. Then, a DC voltage is applied to the treatment liquid in the intermediate storage tank to collect foreign matter in the treatment liquid on the electrode, and then the treatment liquid in the intermediate storage tank from which the foreign matter has been removed is supplied to the supply nozzle, After stopping the supply of the processing liquid to the supply nozzle, the polarity of the DC voltage applied to the electrode is reversed or the application of the voltage to the electrode is stopped, and then the cleaning liquid is supplied to the intermediate storage tank and the intermediate storage tank Washing inside, then inside said The cleaning liquid in the storage tank, is characterized by discharging to the outside of the said intermediate reservoir.

  At least while the voltage is applied to the electrode, the processing liquid stored in the intermediate storage tank and the electrode may be relatively moved.

  The electrode may be formed in a mesh shape.

  Either one of the positive electrode and the negative electrode of the electrode is formed in a mesh plate shape parallel to the bottom surface of the intermediate storage tank, and is provided inside the intermediate storage tank, and the other electrode is outside the intermediate storage tank. The relative movement between the treatment liquid and the electrode may be performed by moving up and down a pole provided in the intermediate storage tank in the vertical direction.

  Either one of the positive electrode and the negative electrode of the electrode is formed in a mesh plate shape, and is provided along the rotation axis provided in the vertical direction inside the intermediate storage tank, and the other electrode is The relative movement between the treatment liquid and the electrode provided outside the intermediate storage tank may be performed by rotating the rotating shaft.

  The electrode is formed in a mesh plate shape parallel to the bottom surface of the intermediate storage tank, and a plurality of positive electrodes and negative electrodes of the electrode are alternately arranged inside the intermediate storage tank along the height direction of the intermediate storage tank. It may be.

  The processing liquid supply pipe is provided with a plurality of the intermediate storage tanks provided with the electrodes in parallel, and the cleaning is not performed when the inside of the intermediate storage tank that has supplied the processing liquid to the supply nozzle is cleaned. The processing liquid may be continuously supplied to the supply nozzle by starting the supply of the processing liquid from which the foreign matters have been removed from the intermediate storage tank to the supply nozzle.

  According to another aspect of the present invention, there is provided a program that operates on a computer of a control device that controls the processing liquid supply system in order to cause the processing liquid supply apparatus to execute the processing liquid supply method.

  According to another aspect of the present invention, a computer-readable storage medium storing the program is provided.

  According to the present invention, nano-order minute particles contained in the treatment liquid can be efficiently removed.

It is a top view which shows the outline of the internal structure of the substrate processing system concerning this Embodiment. It is a side view which shows the outline of the internal structure of the substrate processing system concerning this Embodiment. It is a side view which shows the outline of the internal structure of the substrate processing system concerning this Embodiment. It is explanatory drawing of the longitudinal cross-section which shows the outline of a structure of a development processing unit. It is explanatory drawing of the cross section which shows the outline of a structure of a development processing unit. It is explanatory drawing which shows the outline of a structure of a developing solution supply apparatus. It is explanatory drawing which shows the state of a microparticle at the time of applying a voltage to an electrode. It is explanatory drawing which shows the state of a microparticle at the time of applying a voltage to an electrode. It is explanatory drawing which shows the outline of a structure of the developing solution supply apparatus concerning other embodiment. It is explanatory drawing which shows the outline of arrangement | positioning of the electrode concerning other embodiment. It is explanatory drawing which shows the outline of arrangement | positioning of the electrode concerning other embodiment. It is explanatory drawing which shows the outline of arrangement | positioning of the electrode concerning other embodiment. It is explanatory drawing which shows the outline of a structure of the developing solution supply apparatus concerning other embodiment. It is explanatory drawing which shows the outline of a structure of the conventional process liquid supply apparatus.

  Embodiments of the present invention will be described below. FIG. 1 is an explanatory diagram illustrating an outline of an internal configuration of a substrate processing system 1 including a processing liquid supply apparatus according to the present embodiment. 2 and 3 are side views showing an outline of the internal configuration of the substrate processing system 1. In the present embodiment, the substrate processing system 1 is, for example, a coating and developing processing system that performs photolithography processing of a substrate, and the processing liquid is, for example, a developing solution or pure water used for coating and developing processing. An example will be described.

  As shown in FIG. 1, the substrate processing system 1 includes, for example, a cassette station 2 as a loading / unloading unit for loading / unloading a cassette C to / from the outside, and a plurality of single-wafer processing in a photolithography process. A configuration in which a processing station 3 as a processing unit including the various processing units and an interface station 5 as a transfer unit that transfers the wafer W between the exposure apparatus 4 adjacent to the processing station 3 are integrally connected. Have. In addition, the substrate processing system 1 includes a control device 6 that controls the substrate processing system 1.

  The cassette station 2 is divided into, for example, a cassette carry-in / out unit 10 and a wafer transfer unit 11. For example, the cassette loading / unloading unit 10 is provided at the end of the substrate processing system 1 on the Y direction negative direction (left direction in FIG. 1) side. The cassette loading / unloading unit 10 is provided with a cassette mounting table 12. A plurality, for example, four mounting plates 13 are provided on the cassette mounting table 12. The mounting plates 13 are arranged in a line in the horizontal X direction (up and down direction in FIG. 1). The cassettes C can be placed on these placement plates 13 when the cassettes C are loaded into and unloaded from the substrate processing system 1.

  The wafer transfer unit 11 is provided with a wafer transfer device 21 that is movable on a transfer path 20 extending in the X direction as shown in FIG. The wafer transfer device 21 is also movable in the vertical direction and the vertical axis (θ direction), and is provided between a cassette C on each mounting plate 13 and a delivery device for a third block G3 of the processing station 3 to be described later. Wafers W can be transferred between them.

  The processing station 3 is provided with a plurality of, for example, four blocks G1, G2, G3, and G4 having various units. For example, the first block G1 is provided on the front side of the processing station 3 (X direction negative direction side in FIG. 1), and the second side is provided on the back side of the processing station 3 (X direction positive direction side in FIG. 1). Block G2 is provided. Further, a third block G3 is provided on the cassette station 2 side (Y direction negative direction side in FIG. 1) of the processing station 3, and the processing station 3 interface station 5 side (Y direction positive direction side in FIG. 1). Is provided with a fourth block G4.

  For example, in the first block G1, as shown in FIG. 2, a plurality of liquid processing units, for example, a development processing unit 30 for developing the wafer W, an antireflection film (hereinafter referred to as “lower antireflection”) under the resist film of the wafer W. A lower antireflection film forming unit 31 for forming a film), a resist coating unit 32 for forming a resist film by applying a resist solution as a processing liquid on the wafer W, and an antireflection film (on the upper layer of the resist film on the wafer W). The upper antireflection film forming units 33 forming the “upper antireflection film” are stacked in four stages in order from the bottom. In addition, a chemical chamber 34 for supplying various processing liquids to each liquid processing unit in the block G1 is provided at the lowermost stage of the first block G1.

  For example, each unit 30 to 33 of the first block G1 has a plurality of cups F that accommodate the wafer W in the horizontal direction during processing, and can process the plurality of wafers W in parallel.

  For example, in the second block G2, as shown in FIG. 3, a heat treatment unit 40 for performing heat treatment of the wafer W, an adhesion unit 41 as a hydrophobizing apparatus for hydrophobizing the wafer W, and an outer peripheral portion of the wafer W The peripheral exposure unit 42 for exposing the light is arranged in the vertical direction and the horizontal direction. The heat treatment unit 40 has a hot plate for placing and heating the wafer W and a cooling plate for placing and cooling the wafer W, and can perform both heat treatment and cooling treatment. The number and arrangement of the heat treatment unit 40, the adhesion unit 41, and the peripheral exposure unit 42 can be arbitrarily selected.

  For example, in the third block G3, a plurality of delivery units 50, 51, 52, 53, 54, 55, and 56 are provided in order from the bottom. In the fourth block G4, a plurality of delivery units 60, 61, 62 and a defect inspection unit 63 are provided in order from the bottom.

  As shown in FIG. 1, a wafer transfer region D is formed in a region surrounded by the first block G1 to the fourth block G4. For example, a wafer transfer device 70 is disposed in the wafer transfer region D.

  The wafer transfer device 70 has a transfer arm that is movable in the Y direction, the front-rear direction, the θ direction, and the vertical direction, for example. The wafer transfer device 70 moves in the wafer transfer area D and transfers the wafer W to a predetermined unit in the surrounding first block G1, second block G2, third block G3, and fourth block G4. it can. For example, as shown in FIG. 3, a plurality of wafer transfer apparatuses 70 are arranged in the vertical direction, and can transfer the wafer W to a predetermined unit having the same height of each of the blocks G1 to G4, for example.

  Further, in the wafer transfer region D, a shuttle transfer device 80 that transfers the wafer W linearly between the third block G3 and the fourth block G4 is provided.

  The shuttle conveyance device 80 is linearly movable in the Y direction of FIG. 3, for example. The shuttle transfer device 80 moves in the Y direction while supporting the wafer W, and can transfer the wafer W between the transfer unit 52 of the third block G3 and the transfer unit 62 of the fourth block G4.

  As shown in FIG. 1, a wafer transfer device 90 is provided on the positive side in the X direction of the third block G3. The wafer transfer device 90 has a transfer arm that is movable in the front-rear direction, the θ direction, and the vertical direction, for example. The wafer transfer device 90 moves up and down while supporting the wafer W, and can transfer the wafer W to each delivery unit in the third block G3.

  The interface station 5 is provided with a wafer transfer device 100. The wafer transfer apparatus 100 has a transfer arm that is movable in the front-rear direction, the θ direction, and the vertical direction, for example. The wafer transfer apparatus 100 can transfer the wafer W to the transfer units and the exposure apparatus 4 in the fourth block G4, for example, by supporting the wafer W on the transfer arm.

  Next, the configuration of the development processing unit 30 will be described.

  FIG. 4 is an explanatory view of a vertical section showing an outline of the configuration of the development processing unit 30, and FIG. 5 is an explanatory view of a cross section showing an outline of the configuration of the development processing unit 30.

  As shown in FIG. 4, the development processing unit 30 has a processing container 120 whose inside can be closed. As shown in FIG. 5, a loading / unloading port 121 for the wafer W is formed on the side surface of the processing container 120 facing the loading region of the first transfer arm 10, and an opening / closing shutter 122 is provided at the loading / unloading port 121.

  A spin chuck 130 for holding and rotating the wafer W is provided at the center of the processing container 120 as shown in FIG. The spin chuck 130 has a horizontal upper surface, and a suction port (not shown) for sucking the wafer W, for example, is provided on the upper surface. By suction from the suction port, the wafer W can be sucked and held on the spin chuck 130.

  The spin chuck 130 has a chuck drive mechanism 131 including a motor, for example, and can be rotated at a predetermined speed by the chuck drive mechanism 131. Further, the chuck drive mechanism 131 is provided with an elevating drive source such as a cylinder, and the spin chuck 130 can move up and down.

  Around the spin chuck 130, a cup 132 that receives and collects the liquid scattered or dropped from the wafer W is provided. A discharge pipe 133 that discharges the collected liquid and an exhaust pipe 134 that exhausts the atmosphere in the cup 132 are connected to the lower surface of the cup 132.

  As shown in FIG. 5, a rail 140 extending along the Y direction (left and right direction in FIG. 5) is formed on the X direction negative direction (downward direction in FIG. 5) side of the cup 132. The rail 140 is formed, for example, from the outside of the cup 132 in the Y direction negative direction (left direction in FIG. 5) to the outside in the Y direction positive direction (right direction in FIG. 5). An arm 141 is attached to the rail 140.

  As shown in FIGS. 4 and 5, the arm 141 supports a developer nozzle 142 as a supply nozzle that discharges the developer to the substrate. The arm 141 is movable on the rail 140 by a nozzle driving unit 143 shown in FIG. As a result, the developer nozzle 142 can move from the standby unit 144 installed outside the positive direction of the Y direction of the cup 132 to above the center of the wafer W in the cup 132, and further on the surface of the wafer W. It can move in the radial direction of the wafer W. The arm 141 can be moved up and down by a nozzle driving unit 143 and the height of the developer nozzle 142 can be adjusted. As shown in FIG. 4, the developer nozzle 142 is connected to a developer supply device 190 as a processing solution supply device.

  Further, another arm 150 is attached to the rail 140. The other arm 150 supports a pure water nozzle 151 for supplying pure water as a surface treatment liquid. The other arm 150 is movable on the rail 140 by the nozzle driving unit 152 shown in FIG. 5, and the pure water nozzle 151 is moved from the standby unit 153 provided outside the Y direction negative side of the cup 132. It can be moved to above the center of the wafer W in the cup 22. Further, the other arm 150 can be raised and lowered by the nozzle driving unit 152, and the height of the pure water nozzle 151 can be adjusted. As shown in FIG. 4, the pure water nozzle 151 is connected to a pure water supply device 200 as a processing liquid supply device.

  Next, the configuration of the developing solution supply apparatus 190 that supplies the developing solution as the processing solution to the developing solution nozzle 142 in the developing processing unit 30 will be described. FIG. 6 is an explanatory diagram showing an outline of the configuration of the developer supply device 190. Note that the developer supply device 190 is provided, for example, in the chemical chamber 24 shown in FIG.

  The developer supply device 190 has a developer storage tank 201 as a processing solution supply source for storing the developer. The developer storage tank 201 is provided with a developer supply pipe 202 for supplying the developer to the developer nozzle 142. That is, the developer supply pipe 202 is provided by connecting the developer storage tank 201 and the developer nozzle 142.

  An intermediate storage tank 203 is provided between the developer storage tank 201 and the developer nozzle 142 to temporarily store the developer supplied from the developer storage tank 201 via the developer supply pipe 202. The intermediate storage tank 203 is formed in, for example, a bottomed cylindrical shape with an open top. The intermediate storage tank 203 serves as a buffer tank, and supplies the developer stored in the intermediate storage tank 203 to the developer nozzle 142 even when the developer supplied from the developer storage tank 201 runs out. Can do.

  An electrode 204 for applying a DC voltage to the developer in the intermediate storage tank 203 is provided inside the intermediate storage tank 203. The electrode 204 is formed in, for example, a flat plate shape, and a positive electrode and a negative electrode are arranged in the intermediate storage tank 203 with a predetermined distance therebetween. A power supply unit 205 that applies a DC voltage to the electrode 204 is connected to the electrode 204. The power supply unit 205 can start and stop the application of a voltage to the electrode 204 and reverse the polarity of the applied voltage.

  A cleaning liquid supply pipe 210 for supplying a cleaning liquid into the intermediate storage tank 203 is provided at the opening above the intermediate storage tank 203 as shown in FIG. A cleaning liquid supply source 211 that supplies the cleaning liquid to the cleaning liquid supply pipe 210 is connected to the end of the cleaning liquid supply pipe 210 opposite to the intermediate storage tank 203 side. The cleaning liquid in the present embodiment is pure water, for example, but for example, a developer or thinner can be used, and can be arbitrarily selected according to the type of processing liquid. The cleaning liquid supply pipe 210 is provided with a valve 212 for controlling the supply of the cleaning liquid to the intermediate storage tank 203. For example, an air operation valve is used as the valve 212.

  A waste liquid pipe 220 for discharging the cleaning liquid supplied from the cleaning liquid supply pipe 210 from the intermediate storage tank 203 is provided below the side or bottom of the intermediate storage tank 203, more specifically below the electrode 204. The waste liquid pipe 220 is provided with a valve 221, and the cleaning liquid supplied to the intermediate storage tank 203 can be discharged via the waste liquid pipe 220 by opening the valve 221. As the valve 221, for example, an air operation valve is used similarly to the above-described valve 212. A waste liquid part 222 is provided at the end of the waste liquid pipe 220 opposite to the side connected to the intermediate storage tank 203, and the cleaning liquid is discharged from the waste liquid pipe 220 to the waste liquid part 222.

  Further, inside the intermediate storage tank 203, a stirrer 223 as a stirring mechanism for stirring the developer and the cleaning liquid stored in the intermediate storage tank 203 is provided. By this stirrer 223, for example, a swirling flow of the developer around the central vertical axis of the intermediate reservoir is formed in the intermediate reservoir 203, and the developer and the electrode 204 can be moved relative to each other.

  As shown in FIG. 6, the developer supply pipe 202 on the downstream side of the intermediate reservoir 203 is provided with a pump 230 that pumps the developer in the intermediate reservoir 203 to the developer nozzle 142. As the pump 230, for example, a tube fram type pump is used. A valve 231 is provided in the developer supply pipe 202 on the downstream side of the pump 230. For example, an air operation valve is used as the valve 231.

  Control of application of the DC voltage to the electrode 204 by the power supply unit 205, driving operation of the pump 230, and opening / closing operation of each valve are controlled by the control device 6. The control device 6 is configured by a computer including, for example, a CPU and a memory. For example, by executing a program stored in the memory, the supply of the developer by the developer supply device 190 and the development in the development processing unit 30 are performed. Processing can be realized. Various programs for realizing the supply of the developer by the developer supply device 190 and the development processing in the development processing unit 30 are, for example, a computer-readable hard disk (HD), flexible disk (FD), compact disk (CD). ), Recorded on a computer-readable storage medium H such as a magnetic optical desk (MO) or a memory card, and installed on the control device 6 from the storage medium H.

  The substrate processing system 1 according to the present embodiment is configured as described above. Next, the supply and development of the developer to the developer nozzle 142 performed by the developer supply apparatus 190 configured as described above. A development process performed in the processing unit 30 will be described together with a wafer processing process performed in the entire substrate processing system 1.

  In the processing of the wafer W, first, the cassette C containing a plurality of wafers W is placed on a predetermined cassette placement plate 13 of the cassette station 10. Thereafter, the wafers W in the cassette C are sequentially taken out by the substrate transfer device 21 and transferred to, for example, the transfer device 53 of the third processing unit group G3 of the processing station 11.

  Next, the wafer W is transferred to the heat treatment unit 40 of the second block G2 by the wafer transfer device 70, and the temperature is adjusted. Thereafter, the wafer W is transferred to, for example, the lower antireflection film forming unit 31 of the first block G1 by the wafer transfer device 70, and a lower antireflection film is formed on the wafer W. Thereafter, the wafer W is transferred to the heat treatment unit 40 of the second block G2, and heat treatment is performed. Thereafter, it is returned to the delivery unit 53 of the third block G3.

  Next, the wafer W is transferred to the delivery unit 54 of the same third block G3 by the wafer transfer device 90. Thereafter, the wafer W is transferred to the adhesion unit 41 of the second block G2 by the wafer transfer device 70 and subjected to a hydrophobic treatment. Thereafter, the wafer W is transferred to the resist coating unit 32 by the wafer transfer device 70.

  When a resist film is formed on the wafer W in the resist coating unit 32, the wafer W is transferred to the heat treatment unit 40 by the wafer transfer device 70 and prebaked. Thereafter, the wafer W is transferred by the wafer transfer apparatus 70 to the delivery unit 55 of the third block G3.

  Next, the wafer W is transferred to the upper antireflection film forming unit 33 by the wafer transfer device 70, and an upper antireflection film is formed on the wafer W. Thereafter, the wafer W is transferred to the heat treatment unit 40 by the wafer transfer device 70, heated, and the temperature is adjusted. Thereafter, the wafer W is transferred to the peripheral exposure unit 42 and subjected to peripheral exposure processing.

  Thereafter, the wafer W is transferred to the delivery unit 56 of the third block G3 by the wafer transfer device 70. Next, the wafer W is transferred to the transfer unit 52 by the wafer transfer device 90 and transferred to the transfer unit 62 of the fourth block G4 by the shuttle transfer device 80. Thereafter, the wafer W is transferred to the exposure apparatus 4 by the wafer transfer apparatus 100 of the interface station 7 and subjected to exposure processing.

  Next, the wafer W is transferred by the wafer transfer apparatus 100 to the delivery unit 60 of the fourth block G4. Thereafter, the wafer W is transferred to the heat treatment unit 40 by the wafer transfer device 70 and subjected to post-exposure baking. Thereafter, the wafer W is transferred to the development processing unit 30 by the wafer transfer device 70 and developed. The development processing in the development processing unit 30 will be described later. After the development is completed, the wafer W is transferred to the heat treatment unit 40 by the wafer transfer device 90 and subjected to a post-bake process.

  Thereafter, the wafer W is transferred to the delivery unit 50 of the third block G3 by the wafer transfer device 70, and then transferred to the cassette C of the predetermined cassette mounting plate 13 by the wafer transfer device 21 of the cassette station 2. In this way, a series of photolithography processes are completed, and this process is repeated.

  Next, a series of development processes in which the developer is supplied from the developer supply apparatus 190 to the developer nozzle 142 of the development unit 30 and the developer is supplied to the wafer W by the development unit 30 will be described.

  First, a so-called pre-wet process is performed prior to the development process. In performing the pre-wetting process, first, the pure water nozzle 151 of the standby unit 153 is moved above the wafer W by the other arm 150. Thereafter, pure water is supplied from the pure water nozzle 151, and the wafer W is pre-wet processed.

  Next, the control device 6 opens the valve 231 and pressurizes the inside of the developer storage tank 201. Then, the developer is pumped from the developer storage tank 201 to the intermediate storage tank 203 and temporarily stored in the intermediate storage tank 203. When a predetermined amount of developer is stored in the intermediate storage tank 203, the controller 6 then operates the power supply unit 205 to apply a DC voltage to the electrode 204. In addition, the stirrer 223 is activated along with the application of the voltage to the electrode 204. As a result, the developer in the intermediate storage tank 203 is agitated, and the developer contacts the electrode 204 without being biased. At this time, as shown in FIG. 7, the minute particles P in the developer that could not be removed by the conventional filter are attracted to and collected by the electrode 204 according to their own charges. Thereby, the minute particles P are removed from the developer in the intermediate storage tank 203.

  Thereafter, the pump 230 is operated to supply the developer from which the fine particles P have been removed to the developer nozzle 142. Next, in the development processing unit 30, the wafer W adsorbed by the spin chuck 130 is rotated by the chuck drive mechanism 131 and the developer is supplied from the developer nozzle 142 to the wafer W. The developer supplied to the wafer W is diffused over the entire surface of the wafer W by centrifugal force generated by the rotation of the wafer W. Thereafter, the rotation of the wafer W is stopped and development processing is performed. Note that the stirrer 223 may be stopped after the fine particles P in the developer are removed by the electrode 204.

  After dropping of the developing solution from the developing solution nozzle 142 onto the wafer W is completed, the control device 6 closes the valve 231 of the developing solution supply pipe 202. Next, pure water is supplied from the pure water nozzle 151 to the wafer W, and the developer on the wafer W is washed away. The pure water nozzle 151 supplies pure water from which the fine particles P have been removed by the pure water supply device 200, as in the case of the developer.

  Thereafter, the supply of pure water is stopped, the pure water nozzle 151 is retracted to the standby unit 153, the wafer W is rotated at a predetermined rotation speed for a predetermined time, and spin drying is performed. Thereafter, the wafer W is transferred from the development processing apparatus 1 by a transfer mechanism (not shown). Then, a new wafer W is carried into the development processing unit 30 and a series of development processing is repeatedly performed.

  When the development process is repeated, the collected fine particles P are deposited on the surface of the electrode 204. For this reason, the electrode 204 is cleaned. In cleaning the electrode 204, first, the stirrer 223 is stopped, and then the valve 212 of the cleaning liquid supply pipe 210 is opened to supply the cleaning liquid into the intermediate storage tank 203. Thereafter, the polarity of the DC voltage applied to the electrode 204 by the power supply unit 205 is reversed by the control device 6. Thereby, for example, as shown in FIG. 8, the minute particles P attracted to the electrode 204 are discharged into the cleaning liquid. Next, the application of voltage is stopped so that the fine particles released into the cleaning liquid do not adhere to the electrode 204 again.

Thereafter, the control device 6 opens the valve 221 of the waste liquid pipe 220, and the cleaning liquid containing the fine particles P is discharged from the waste liquid pipe 220. Thereby, the inside of the electrode 204 and the intermediate storage tank 203 is cleaned, and this cleaning is continuously performed for a predetermined time. About the time which continues washing | cleaning, it determines based on the result of the preliminary test performed previously. In addition, since the minute particle P has an electric charge, for example, when the conductivity of the cleaning liquid is measured by providing a conductivity meter in the waste liquid tube 220 or the waste liquid part 222, and the conductivity becomes a predetermined value or less. You may make it stop washing | cleaning.

  When the cleaning of the intermediate storage tank 203 is completed, the valves 212 and 221 are closed by the control device 6. Thereafter, the developing solution is supplied again from the developing solution storage tank 201 to the intermediate storage tank 203, and a series of development processing is repeated.

  According to the above embodiment, the DC voltage is applied to the electrode 204 provided in the intermediate storage tank 203 to remove the minute particles P that cannot be removed by the conventional filter, and then the polarity of the voltage applied to the electrode 204 is changed. Since the cleaning liquid is supplied into the intermediate storage tank 203 in a state where the microparticles P are reversed and discharged from the electrode 204, the microparticles P collected by the electrode 204 can be quickly discharged out of the intermediate storage tank 203. . For this reason, the inside of the intermediate storage tank 203 can be kept clean. Therefore, according to the present invention, fine particles P of about several tens of nm, which have been difficult to remove with a conventional filter, are removed from the developer, and the developer supply pipe 202 is provided like a conventional filter. Since clogging does not occur in the interior, maintenance becomes easy. Therefore, it is possible to efficiently remove the fine particles P.

  Further, since it is not necessary to provide a filter in the developer supply pipe 202 as in the prior art, the pressure loss in the developer supply pipe 202 can be reduced. Therefore, the pump 230 can be downsized and its power can be reduced.

  In addition, since the electrodes 204 are provided in the intermediate storage tank 203 to remove the fine particles P, the discharge operation of the processing liquid such as the developer and the removal operation of the fine particles P from the processing liquid are performed independently. And the fine particles P can be removed more effectively.

  Further, since the stirrer 223 is provided in the intermediate storage tank 203, a stirring flow can be formed in the intermediate storage tank 203. As a result, since the minute particles P and the electrode 204 can be brought into contact with each other without unevenness, the minute particles can be efficiently removed by the electrode 204 without increasing the size of the electrode 204.

  In the above embodiment, the example in which the electrode 204 is cleaned after the development process is repeated a certain number of times has been described. However, the timing for cleaning the electrode 204 can be arbitrarily set, for example, an intermediate storage tank It may be performed when the liquid level of the developer in 203 is lowered and the intermediate reservoir 203 is replenished with developer. Further, the electrode 204 can be cleaned by various procedures other than the above-described embodiment. For example, after reversing the polarity of the voltage applied to the electrode 204, the valve 221 of the waste liquid pipe 220 is opened, the fine particles P are discharged together with the developer remaining in the intermediate storage tank 203, the valve 221 is then closed, and then the cleaning liquid is supplied. The valve 212 of the pipe 210 may be opened for cleaning, and the valve 221 may be opened again to discharge the cleaning liquid.

  Further, when convection of the processing liquid naturally occurs in the intermediate storage tank 203 due to the shape of the intermediate storage tank 203 and the electrode 204 and the arrangement setting of the developer supply pipe 202 and the waste liquid pipe 220, the stirrer 223 is not necessarily provided. .

  In the above embodiment, the cleaning liquid is directly supplied to the intermediate storage tank 203 through the cleaning liquid supply pipe 210. However, as shown in FIG. 9, for example, the development is such that the cleaning liquid supply pipe 210 is located upstream of the intermediate storage tank 203. The cleaning liquid may be supplied to the liquid supply pipe 202 via the developer supply pipe 202.

  Further, the waste liquid pipe 220 may be connected to the developer supply pipe 202 on the downstream side of the intermediate storage tank 203 and supplied with the cleaning liquid through the developer supply pipe 202. In such a case, as shown in FIG. 10, the developer supply pipe 202 is disposed below the side surface of the intermediate storage tank 203 so that the developer or cleaning liquid can be discharged from the waste liquid pipe 220 by its own weight even when the pump 230 is not operated. The bottom portion is provided below the electrode 204.

  In the above embodiment, the electrode 204 has a flat plate shape, but the shape of the electrode is not limited to this example, and can be arbitrarily set according to the size and shape of the intermediate storage tank 203. is there. For example, the electrode 204 may be formed in a mesh shape in order to increase the contact area between the developer and the electrode 204 and increase the collection efficiency of the fine particles P by the electrode 204.

  In the case of using a mesh electrode, for example, as shown in FIG. 10, a mesh plate in which either the positive electrode or the negative electrode is parallel to the bottom surface of the intermediate storage tank 203 and conforms to the shape of the inner surface of the intermediate storage tank 203. You may use the electrode 240 formed in the shape. In this case, the other pole of the electrode 240 is formed along the shape of the outer surface of the intermediate storage tank 203 and provided outside the intermediate storage tank 203. When the electrode 240 is used, an elevating mechanism 241 that elevates the electrode 240 in the vertical direction is provided, and this elevating mechanism acts as a stirring mechanism. In FIG. 10, for convenience of illustration, only a part of the electrode 240 provided outside the intermediate storage tank 203 is depicted.

  As another form of the electrode, for example, as shown in FIG. 11, a mesh plate-like electrode 251 provided along the rotation shaft 250 provided in the vertical direction inside the intermediate storage tank 203 is used. May be. The rotating shaft 250 is formed of a conductive material, and is configured to be rotatable along the circumferential direction of the intermediate storage tank 203 by a rotating mechanism 252. In such a case, the rotating mechanism 252 acts as a stirring mechanism. Similarly to the electrode 240 shown in FIG. 10, the other electrode 251 is formed along the shape of the outer surface of the intermediate storage tank 203 and provided outside the intermediate storage tank 203.

  As shown in FIGS. 10 and 11, the electrodes 240 and 251 are formed in a mesh shape, and the electrodes 240 and 251 are moved in the intermediate storage tank 203, so that foreign matters in the liquid in the intermediate storage tank 203 are uniformly removed. be able to. In particular, as shown in FIG. 10, by using a mesh plate electrode 240 similar to the bottom surface of the intermediate storage tank 203, for example, even when the level of the developer in the intermediate storage tank 203 is lowered, the electrode 240 is used. Since the contact area between the developer and the developer can always be kept constant, the fine particles P can be efficiently removed without being affected by the remaining amount of developer in the intermediate storage tank 203. In FIG. 11, the electrode 251 on the side provided inside the intermediate storage tank 203 is drawn to be shorter than the radius of the intermediate storage tank 203, but the length of the electrode 251 in the diameter direction of the intermediate storage tank 203 is illustrated. Can be set arbitrarily.

  Further, for example, as shown in FIG. 12, the positive electrode and the negative electrode of the electrode 260 formed parallel to the bottom surface of the intermediate storage tank 203 and in the shape of a mesh plate are placed inside the intermediate storage tank 203 along the height direction of the intermediate storage tank 203. May be arranged alternately. In such a case, the developer supply pipe 202 on the downstream side of the intermediate storage tank 203 allows the developer supplied from the upper part of the intermediate storage tank 203 to be discharged after passing through the electrode 260 located at the farthest place. Preferably they are arranged. Specifically, the developer supply pipe 202 is provided, for example, on the lower side or bottom of the intermediate storage tank 203. By doing so, since the developer flows in the intermediate storage tank 203 so as to cross the surface of the electrode 260 vertically, the fine particles P can be efficiently removed by the electrode 260 without providing a stirring mechanism.

  In particular, when the electrode 260 is used, clogging of the electrode 260 can be suppressed by decreasing the number of meshes of the electrode 260 in the order from the top to the bottom of the intermediate storage tank 203, for example. In such a case, the cleaning liquid supply pipe 210 may be provided, for example, at the bottom of the intermediate storage tank 203, and the waste liquid pipe 220 may be discharged, for example, from above the electrode 260 provided at the top of the intermediate storage tank 203. . By doing so, it is possible to form a flow of cleaning liquid from the finer mesh to the coarser mesh, so that the fine particles P collected by the electrode 260 can be efficiently removed.

  In the above embodiment, one intermediate storage tank 203 is provided for one developer nozzle 142. However, as shown in FIG. 13, for example, a plurality of intermediate storage tanks 203 are provided in the developer supply pipe 202. You may arrange | position in parallel. Valves 270 are respectively provided on the upstream side and the downstream side of the intermediate storage tanks 203 arranged in parallel. By operating the valves 270, the supply of the developer to the developer nozzle 142 can be made to any of the intermediate storage tanks 203. You can choose whether to do from. In such a case, even when one intermediate storage tank 203 and the electrode 204 are washed, the developer from which the foreign matters are removed can be supplied from the other intermediate storage tank 203 to the developer nozzle 142. For this reason, the supply of the developer does not stop when the intermediate storage tank 203 is washed, and the developer from which the foreign matters are removed can be continuously supplied to the developer nozzle 142. In FIG. 13, two intermediate storage tanks 203 are provided in parallel, but the number of intermediate storage tanks 203 can be set arbitrarily. For example, when a plurality of developer nozzles 142 are provided, the developer supply device 190 may be shared between the plurality of developer nozzles 142.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. It is understood. The present invention is not limited to this example, and can take various forms. For example, when supplying other processing liquids such as thinner which is a solvent of resist liquid used for pre-wetting before resist liquid application. Applicable. The present invention can also be applied to a case where the substrate is another substrate such as an FPD (flat panel display) other than a wafer, a mask reticle for a photomask, or the like.

  The present invention is useful when supplying a processing liquid to a substrate such as a semiconductor wafer.

DESCRIPTION OF SYMBOLS 1 Substrate processing system 2 Cassette station 3 Processing station 4 Exposure apparatus 5 Interface station 6 Control apparatus 10 Cassette carrying-in part 11 Wafer conveyance part 12 Cassette mounting stand 13 Mounting plate 20 Conveyance path 21 Wafer conveyance apparatus 30 Development processing unit 31 Lower part antireflection Film forming unit 32 Resist coating unit 33 Upper antireflection film forming unit 34 Chemical chamber 40 Heat treatment unit 41 Adhesion unit 42 Peripheral exposure unit 70 Wafer transfer device 80 Shuttle transfer device 90 Wafer transfer device 100 Wafer transfer device 120 Processing vessel 130 Spin Chuck 132 Cup 140 Rail 141 Arm 142 Application nozzle 190 Developer supply device 200 Pure water supply device 201 Developer solution storage tank 202 Developer solution pipe 203 Storage tank 204 Electrode 205 Power supply unit 210 Cleaning liquid supply pipe 211 Cleaning liquid supply source 212 Valve 220 Waste liquid pipe 221 Valve 222 Waste liquid part 223 Stirrer 230 Pump 231 Valve 240 Electrode 241 Lifting mechanism 250 Rotating shaft 251 Electrode 252 Rotating mechanism 260 Electrode W Wafer D Wafer transfer area C Cassette P Fine particles

Claims (16)

A processing liquid supply device for supplying a processing liquid from a processing liquid supply source to a supply nozzle for supplying a processing liquid to a substrate through a processing liquid supply pipe,
An intermediate storage tank that is provided between the processing liquid supply source and the supply nozzle in the processing liquid supply pipe and temporarily stores the processing liquid supplied from the processing liquid supply source;
The intermediate storage tank, an electrode for applying a DC voltage to the processing liquid stored in the intermediate storage tank,
A power supply unit that applies a DC voltage to the electrode so as to freely reverse the polarity;
A cleaning liquid supply pipe for supplying a cleaning liquid to the intermediate storage tank;
And a waste liquid pipe for discharging the cleaning liquid from the intermediate storage tank. The processing liquid supply apparatus according to claim 1, wherein the intermediate storage tank is provided with a stirring mechanism that relatively moves the processing liquid stored in the intermediate storage tank and the electrode. The processing liquid supply apparatus according to claim 1, wherein the electrode is formed in a mesh shape. Either one of the positive electrode and the negative electrode of the electrode is formed in a mesh plate shape parallel to the bottom surface of the intermediate storage tank, and is provided inside the intermediate storage tank.
The other pole is provided outside the intermediate storage tank,
The processing liquid supply apparatus according to claim 2, wherein the agitation mechanism is an elevating mechanism that elevates and lowers one of the poles provided in the intermediate storage tank in the vertical direction. Either one of the positive electrode and the negative electrode of the electrode is formed in a mesh plate shape, and is provided along the rotation axis provided to extend in the vertical direction inside the intermediate storage tank,
The other pole is provided outside the intermediate storage tank,
The processing liquid supply apparatus according to claim 2, wherein the stirring mechanism is a rotating mechanism that rotates the rotating shaft. The electrode is formed in a mesh plate shape parallel to the bottom surface of the intermediate storage tank,
2. The processing liquid supply apparatus according to claim 1, wherein a plurality of positive electrodes and negative electrodes of the electrode are alternately arranged inside the intermediate storage tank along a height direction of the intermediate storage tank. The processing liquid supply apparatus according to claim 1, wherein a plurality of the intermediate storage tanks are arranged in parallel in the processing liquid supply pipe. A processing liquid supply method for supplying a processing liquid from a processing liquid supply source to a supply nozzle for supplying a processing liquid to a substrate through a processing liquid supply pipe,
The processing liquid supplied from the processing liquid supply source is temporarily stored in an intermediate storage tank provided between the processing liquid supply source and the supply nozzle in the processing liquid supply pipe,
Then, through the electrode provided in the intermediate storage tank, to apply a DC voltage to the processing liquid in the intermediate storage tank to collect the foreign matter in the processing liquid to the electrode,
Thereafter, the processing liquid in the intermediate storage tank from which the foreign matter has been removed is supplied to the supply nozzle,
After stopping the supply of the treatment liquid to the supply nozzle, the polarity of the DC voltage applied to the electrode is reversed or the application of the voltage to the electrode is stopped,
Thereafter, supplying a cleaning liquid to the intermediate storage tank to clean the inside of the intermediate storage tank,
Then, the cleaning liquid in the intermediate storage tank is discharged outside the intermediate storage tank. The processing liquid supply method according to claim 8, wherein the processing liquid stored in the intermediate storage tank and the electrode are relatively moved at least while a voltage is applied to the electrode. 10. The processing liquid supply method according to claim 8, wherein the electrode is formed in a mesh shape. Either one of the positive electrode and the negative electrode of the electrode is formed in a mesh plate shape parallel to the bottom surface of the intermediate storage tank, and is provided inside the intermediate storage tank.
The other pole is provided outside the intermediate storage tank,
The processing liquid according to claim 9, wherein the relative movement between the processing liquid and the electrode is performed by moving up and down a pole provided in the intermediate storage tank in the vertical direction. Supply method. Either one of the positive electrode and the negative electrode of the electrode is formed in a mesh plate shape, and is provided along the rotation axis provided to extend in the vertical direction inside the intermediate storage tank,
The other pole is provided outside the intermediate storage tank,
The process liquid supply method according to claim 9, wherein the relative movement between the process liquid and the electrode is performed by rotating the rotating shaft. The electrode is formed in a mesh plate shape parallel to the bottom surface of the intermediate storage tank,
The treatment liquid supply method according to claim 8, wherein a plurality of positive electrodes and negative electrodes of the electrode are alternately arranged inside the intermediate storage tank along a height direction of the intermediate storage tank. The treatment liquid supply pipe is provided with a plurality of the intermediate storage tanks provided with the electrodes in parallel,
When cleaning the inside of the intermediate storage tank that has supplied the processing liquid to the supply nozzle, the supply of the processing liquid from which foreign matters have been removed to the supply nozzle from another intermediate storage tank that is not cleaned is started. The process liquid supply method according to claim 8, wherein the process liquid is continuously supplied to the supply nozzle. A program that operates on a computer of a control unit that controls the processing liquid supply device in order to cause the processing liquid supply device to execute the processing liquid supply method according to claim 8. A computer-readable storage medium storing the program according to claim 15.

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