JP4455293B2 - Substrate processing equipment - Google Patents

Description

  The present invention relates to a substrate processing apparatus for performing a predetermined processing such as cleaning with a processing liquid such as pure water on a substrate such as a semiconductor wafer, a glass substrate for a liquid crystal display device, or an electronic component, and in particular, a shower type of processing liquid on the substrate The present invention relates to a substrate processing apparatus that performs processing of discharging and immersing a substrate in a processing solution in one processing tank.

For example, in the manufacturing process of a semiconductor device, when removing contaminants such as particles, organic matter, and metal ions adhering to the surface of a substrate such as a silicon wafer from the substrate surface, a mixed solution of ammonia water and hydrogen peroxide water, The substrate is cleaned using various chemicals such as a mixed solution of hydrochloric acid and hydrogen peroxide solution, or a mixed solution of sulfuric acid and hydrogen peroxide solution, and then the chemical solution remaining on the surface of the substrate and decomposition Unnecessary products such as products and reaction products are removed by washing with pure water. As a method for the water washing treatment, a method of immersing the substrate in the pure water in the treatment tank or the like while continuously supplying pure water into the treatment tank and overflowing the washing water (washed water) from the upper part of the treatment tank, or the like In general, a method of repeatedly immersing the substrate in pure water in the treatment tank while allowing the washing water to overflow and a process of rapidly draining the washing water from the treatment tank are performed several times. Further, the substrate is accommodated in an empty processing tank, and pure water is discharged in a shower shape from the shower nozzle disposed above the processing tank toward the surface of the substrate in the processing tank. The adhering chemicals and unnecessary substances are washed away from the surface of the substrate with pure water, and then the washing water is completely discharged from the treatment tank, and then the pure water is ejected from the nozzle provided in the lower part of the treatment tank. While supplying pure water into the tank and overflowing the washing water from the upper part of the treatment tank, there is a method of immersing the substrate in the pure water in the treatment tank and removing unnecessary materials that could not be washed away by the shower water washing ( For example, see Patent Document 1.)
JP 2000-183011 (page 6-7, FIG. 2, FIG. 5 and FIG. 6)

  In the process of immersing the substrate in pure water after the chemical-treated substrate is washed with shower water, in the immersion treatment after shower water washing, pure water is supplied from the nozzle at the bottom of the treatment tank toward the substrate in the treatment tank. When pure water is supplied into the treatment tank by jetting, the flow of pure water in the treatment tank becomes a turbulent state. For this reason, carbon dioxide gas in the air easily dissolves in the rinsing water in the treatment tank through the overflow surface at the upper part of the treatment tank. Here, in the course of the immersion treatment, the chemical solution adhering to the substrate is dissolved in the pure water in the treatment tank and is discharged from the upper part of the treatment tank together with the washing water to the outside of the treatment tank. At the same time, the specific resistance value of the rinsing water in the treatment tank increases, and therefore, the specific resistance value of the rinsing water in the treatment tank is measured to manage the end point of the immersion treatment. However, as a result of the carbon dioxide gas in the air being dissolved in the rinsing water in the treatment tank, the specific resistance value of the rinsing water in the treatment tank only rises to about 10 MΩ even if the immersion treatment is continued. For this reason, when managing the washing process according to the specific resistance value of the washing water, a final rinse tank in which the flow of pure water in the tank is adjusted to a laminar flow state is installed separately from the treatment tank, and the It is necessary to transfer the substrate from the treatment tank to the final rinse tank and monitor the specific resistance value of the washing water in the final rinse tank. In this way, if a final rinse tank is provided separately from the treatment tank in order to manage the washing state of the substrate with the specific resistance value of the washing water, it requires a lot of installation space, and the equipment cost increases, and a series of The work process is also complicated, and the time required for a series of work is also increased.

  The present invention has been made in view of the circumstances as described above. In the apparatus for processing the substrate by immersing the substrate in the processing liquid after supplying the processing liquid to the substrate in a shower shape and processing the substrate, the processing state of the substrate When the substrate is managed in the state of the processing liquid in which the substrate is immersed, the object is to provide a substrate processing apparatus that does not require a separate processing tank to detect the state of the processing liquid in which the substrate is immersed. To do.

Invention provides a substrate processing apparatus for performing processing on the substrate with pure water, has an opening at the top, a process tank for storing pure water, the substrate holding means for holding the substrate in the processing bath according to claim 1 When the discharge port is provided above the processing bath, and pure water discharging means for discharging the pure water like a shower from the discharge port toward the surface of the substrate in the processing bath, the bottom of the processing bath supply port is provided, by supplying pure water into the processing tank from the supply opening, and pure water supplying means for storing pure water into the processing tank, the outlet is provided at the bottom of the treatment tank, Drain means for discharging flush water in the treatment tank through the discharge port, a lid member that covers the upper opening of the treatment tank so as to be openable and closable, and an inert gas to the surface of the flush water in the treatment tank and the inert gas supply means for supplying a substrate within the processing tank by the pure water discharge means Discharge of the pure water to the surface, the discharge of the washing water from the treatment tank by the drainage means, supply of pure water to the pure water supply means by said processing bath, by the lid member, the pure water supply means A cover for the upper opening of the treatment tank to which pure water is supplied by the gas, and an inert gas to the washing water level in the treatment tank in which the upper opening is covered by the lid member by the inert gas supply means Control means for respectively controlling the supply of water, and a specific resistance meter for measuring the specific resistance value of the washing water in the treatment tank, and based on the specific resistance value measured by the specific resistance meter by the control means The supply of pure water into the treatment tank by the pure water supply means and the supply of inert gas to the washing water level in the treatment tank by the inert gas supply means are stopped, and the lid member is Open the substrate with pure water And a plurality of discharges of pure water onto the substrate surface in the treatment tank by the pure water discharge means and discharge of flush water from the treatment tank by the drain means. Repeatedly, after the final flushing water is discharged from the treatment tank by the drainage means, supply of pure water to the treatment tank by the pure water supply means, upper part of the treatment tank by the lid member Control is performed by the control means so as to start supply of the inert gas to the washing water level in the treatment tank by the cover of the opening and the inert gas supply means .

The invention according to claim 2 is the substrate processing apparatus according to claim 1 , wherein a gas supply port of the inert gas supply means is provided in the lid member.

In the substrate processing apparatus of the invention according to claim 1, pure water by the discharge means, pure water is discharged to a shower shape toward the surface of the substrate held in the processing bath by the substrate holding means, the substrate of the water washing processing is carried out, is discharged pure water in the processing bath by draining means is supplied pure water into the processing bath by pure water supply means, the substrate in the processing tank is immersed in pure water, the substrate water Araisho management is carried out. The upper opening of the treatment tank to which pure water is supplied by the pure water supply means is covered with a lid member, and an inert gas is supplied to the washing water level in the treatment tank whose upper opening is covered with the lid member. since the inert gas is supplied by the supply means, penetration of carbon dioxide in the air into washing water in the processing bath is suppressed.
Thus, using the substrate processing apparatus of the invention according to claim 1, the processing state of the substrate, in the case of managing a state of the washing water in which the substrate is immersed, to detect the state of the washing water in which the substrate is immersed Therefore, it is not necessary to provide a separate processing tank, the installation space can be reduced by that amount, the equipment cost can be kept low, the series of work steps can be simplified, and the time required for the series of operations can be shortened.

Further, in this substrate processing apparatus, the processing state of the substrate can be managed by the specific resistance value of the washing water in the processing tank measured by the specific resistance meter. Then, based on the resistivity value measured by the resistivity meter, the pure water is supplied into the treatment tank by the pure water supply means and the inert gas is supplied to the washing water level in the treatment tank by the inert gas supply means. Are stopped, the lid member is opened, and the cleaning process of the substrate with pure water is terminated.

Further, in the substrate processing apparatus, the discharge of the washing water from the treatment tank by the discharge and drainage means pure water to the substrate surface in the processing bath by pure water discharging means is repeated a plurality of times alternately, by drainage means After the final flushing water discharge from the treatment tank is finished, supply of pure water into the treatment tank by the pure water supply means, a cover for the upper opening of the treatment tank by the lid member, and a treatment tank by the inert gas supply means The supply of the inert gas to each of the rinsing water liquid surfaces starts, and the substrate is suitably processed.

In the substrate processing apparatus of the invention according to claim 2 , since the gas supply port of the inert gas supply means is provided in the lid member, the gas supply port of the inert gas supply means so as not to interfere with the opening / closing operation of the lid member. Compared with the case of providing the device, the structure becomes simple and the size of the device is also reduced.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing a schematic configuration of a substrate processing apparatus according to an embodiment of the present invention.

  The substrate processing apparatus includes a processing tank 10 that is open at the top and stores pure water, and a lifter 12 that holds a plurality of substrates W in the processing tank 10. The lifter 12 is supported so as to be movable up and down between an internal position of the processing tank 10 and an external upper position of the processing tank 10, and is driven up and down by a lifter driving device 14 (a specific mechanism is not shown). Although not shown, a substrate transfer robot is disposed above the processing tank 10, and the substrate W after the chemical solution processing is transferred from the substrate transfer robot to the lifter 12 and transferred into the apparatus. The substrate W that has been subjected to the water washing process at 10 is transferred from the lifter 12 to the substrate transfer robot and is discharged from the apparatus.

  An overflow water tank 16 into which flush water overflowing from the upper part of the treatment tank 10 flows is integrally provided on the upper outer periphery of the treatment tank 10, and the flush water flowing into the overflow water tank 16 is not shown in the figure. It is discharged out of the tank through the pipe. A nozzle 18 is provided in the lower part of the treatment tank 10, and a pure water supply pipe 20 is connected to the nozzle 18 in communication. The pure water supply pipe 20 is connected to a pure water supply source through a flow path, and an open / close control valve 22 is provided in the middle of the pure water supply pipe 20. The pure water supplied to the nozzle 18 through the pure water supply pipe 20 is ejected from the nozzle 18 toward the substrate W in the processing tank 10, supplied to the processing tank 10 and stored. A drain port 24 is formed at the bottom of the treatment tank 10, and a drain pipe 26 is connected to the drain port 24. The diameter of the drain outlet 24 and the inner diameter of the drain pipe 26 are large enough to allow the flush water to be quickly discharged from the treatment tank 10. The drain pipe 26 is provided with an open / close control valve (rapid drain valve) 28.

  A shower nozzle 30 is disposed above the treatment tank 10, and a pure water supply pipe 32 is connected to the shower nozzle 30 in communication therewith. The pure water supply pipe 32 is connected to a pure water supply source, and an open / close control valve 34 is provided in the middle of the pure water supply pipe 32. The pure water supplied to the shower nozzle 30 through the pure water supply pipe 32 is discharged from the shower nozzle 30 toward the surface of the substrate W in the processing bath 10 in a shower shape. Above the shower nozzle 30, a pair of lid members 36 that cover the upper opening of the processing tank 10 are disposed. The lid member 36 is rotatably supported between a closed position indicated by a solid line and an open position indicated by a two-dot chain line, and is opened and closed by a lid member drive device 38 (specific mechanism is not shown). .

  Inside the lid member 36, a gas passage 40 is formed as shown in a cutaway sectional view in FIG. 2, and a gas introduction port 42 is provided so as to communicate with the gas passage 40. Further, the lid member 30 is formed with a plurality of gas outlets 44 respectively communicating with the gas passages 40 on the inner surface facing the upper opening of the processing tank 10 when the lid member 30 is closed. An inert gas, for example, a nitrogen gas supply pipe 46 is connected to the gas inlet 42 of the lid member 36. The nitrogen gas supply pipe 46 is connected to a flow path of a nitrogen gas supply source, and an open / close control valve 48 is provided in the middle of the nitrogen gas supply pipe 46. Then, in a state where the lid member 36 is closed, nitrogen gas is supplied to the gas passage 40 of the lid member 36 through the nitrogen gas supply pipe 46, whereby the treatment tank 10 is supplied from the plurality of gas outlets 44 of the lid member 36. Nitrogen gas blows out toward the surface of the washing water inside.

  Further, this apparatus is provided with a specific resistance meter 50, and a detection unit 52 of the specific resistance meter 50 is disposed in the processing tank 10. The specific resistance meter 50 is connected to the control device 54, and a specific resistance value signal measured by the specific resistance meter 50 is sent to the control device 54. The control device 54 is connected to each of the opening / closing control valves 22, 28, 34, 48, the lifter driving device 14 and the lid member driving device 38, and a control signal is sent from the control device 54 to them.

  Instead of forming the gas outlet 44 in the lid member 30, as shown in FIG. 3, the lid member 56 is positioned between the lid member 56 and the upper opening of the treatment tank 10 in the closed state. Although not shown, a gas blowing nozzle 58 is provided above the processing tank 10, and a nitrogen gas supply pipe that is connected to the nitrogen gas supply source in a flow path may be connected to the gas blowing nozzle 58. .

Next, an example of a substrate washing operation performed using the substrate processing apparatus having the configuration shown in FIG. 1 will be described with reference to the time chart shown in FIG.
When the plurality of substrates W that have been subjected to the chemical solution processing are transferred from the substrate transfer robot to the lifter 12, the lifter 12 is lowered and the substrate W is inserted into the processing tank 10, and the processing tank as shown in FIG. A substrate W is held in the substrate 10. At this time, the lid member 36 is opened as indicated by a two-dot chain line, and all the open / close control valves 22, 28, 34, 48 are closed. When the substrate W is held in the processing tank 10, the open / close control valve 34 provided in the pure water supply pipe 32 is opened for a certain period of time and is directed from the shower nozzle 30 toward the surface of the substrate W in the processing tank 10. Pure water is discharged in the form of a shower, and then the open / close control valve 34 is closed. Thereby, the surface of the substrate W is washed with pure water, and the washed water after washing flows down into the treatment tank 10 and accumulates in the treatment tank 10. At the same time (or before and after) when the open / close control valve 34 is closed, the open / close control valve (rapid drain valve) 28 provided in the drain pipe 26 is opened for a certain period of time, and the flush water accumulated in the treatment tank 10 is collected. Is rapidly discharged from the drainage port 24 through the drainage pipe 26, and then the open / close control valve 28 is closed. Off control valve 28 is opened is the same time (or before and after) again off control valve 34 a predetermined time to close toward the surface of the substrate W in the processing bath 10 from the sheet Yawanozuru 30 in pure water shower form Then, the opening / closing control valve 34 is closed. At the same time (or before and after) when the opening / closing control valve 34 is closed, the opening / closing control valve 28 is opened again for a certain period of time, and the flush water accumulated in the treatment tank 10 passes through the drain pipe 26 from the drain port 24. The valve is quickly discharged, and thereafter the opening / closing control valve 28 is closed.

  When the shower water washing and the rapid drainage are repeated a plurality of times and the final rapid drainage is finished and the opening / closing control valve 28 is closed, the lid member 36 is closed as indicated by the solid line at the same time (or before and after). Then, the upper opening of the processing tank 10 is covered with the lid member 36, the open / close control valve 48 interposed in the nitrogen gas supply pipe 46 is opened, and the inside of the processing tank 10 from the gas outlet 44 of the lid member 36 is opened. Nitrogen gas blows out toward the surface of the rinsing water, the open / close control valve 22 provided in the pure water supply pipe 22 is opened, and pure water blows out from the nozzle 18 toward the substrate W in the treatment tank 10. . Then, the pure water gradually accumulates in the treatment tank 10, the treatment tank 10 is filled with pure water, the pure water overflows from the upper part of the treatment tank 10, and an ascending water flow of pure water is generated in the treatment tank 10. Thus, the substrate W is immersed in the pure water. Thereby, the chemical solution that could not be washed off from the surface of the substrate W by the shower water washing is dissolved in the pure water, and unnecessary substances are removed.

  After performing the above-mentioned immersion treatment for a certain time, or when the specific resistance value of the washing water measured by the specific resistance meter 50 rises to a desired value, for example, 15 MΩ, and the signal is input to the control device 54, The open / close control valve 22 is closed, the supply of pure water from the nozzle 18 into the treatment tank 10 is stopped, the open / close control valve 48 is closed, and the treatment tank 10 is washed with water from the gas outlet 44 of the lid member 36. Blowing off of nitrogen gas to the water surface stops, and the lid member 36 is opened as indicated by a two-dot chain line. Then, the lift 12 is raised, the substrate W is taken out from the processing tank 10, the substrate W is transferred from the lift 12 to the substrate transfer robot, and the substrate W is discharged out of the apparatus by the substrate transfer robot. The series of processing operations described above are executed by the control device 54 controlling the lifter driving device 14, the lid member driving device 38, and the open / close control valves 22, 28, 34, and 48, respectively.

FIG. 5 is a diagram showing how the specific resistance value of the washing water in the treatment tank 10 changes in the series of treatments described above. In the figure, the solid line indicates the change in specific resistance value when the above-described device according to the present invention is used, and the broken line indicates a conventional device, that is, a device that does not include the lid member 36 and the nitrogen gas supply means. The change in specific resistance value is shown. Further, an end point of time t ₁ shower washing, which is the end point of time t ₂ is immersed. As can be seen from the results shown in FIG. 5, when the apparatus according to the present invention is used, pure water is continuously supplied from the nozzle 18 into the treatment tank 10 and the substrate W is immersed in the pure water. During the treatment, the upper opening of the treatment tank 10 is covered with the lid member 36, and nitrogen gas is blown out from the gas blow-out port 44 of the lid member 36 toward the washing water level in the treatment tank 10. Therefore, it is suppressed that the carbon dioxide gas in the air dissolves into the rinsing water in the treatment tank 10. As a result, the specific resistance value of the washing water rises to 15 MΩ or more. For this reason, it is possible to manage the washing process by the specific resistance value of the washing water without installing the final rinse tank in which the flow of pure water in the tank is adjusted to a laminar flow state separately from the treatment tank 10. It becomes.

  In addition, the above-described washing treatment operation of the substrate is an example, and the substrate processing using the substrate processing apparatus according to the present invention can be implemented in various forms.

It is a schematic diagram which shows one example of embodiment of this invention and shows schematic structure of a substrate processing apparatus. FIG. 2 is a cutaway sectional view showing a structure of a lid member that is a component of the substrate processing apparatus shown in FIG. 1. It is a schematic diagram which shows another embodiment of this invention and shows the processing tank part of a substrate processing apparatus. It is a time chart which shows one example of the washing process operation of the board | substrate performed using the substrate processing apparatus provided with the structure shown in FIG. It is a figure for demonstrating the effect when the water washing process of a board | substrate is performed using the substrate processing apparatus provided with the structure shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Treatment tank 12 Lifter 14 Lifter drive device 16 Overflow water tank 18 Nozzle 20, 32 Pure water supply pipe 22, 28, 34, 48 Open / close control valve 24 Drain port 26 Drain pipe 30 Shower nozzle 36, 56 Lid member 38 Lid member drive Device 40 Gas passage 42 Gas inlet 44 Gas outlet 46 Nitrogen gas supply pipe 50 Resistivity meter 54 Controller 58 Gas outlet nozzle W Substrate

Claims (2)

In a substrate processing apparatus for processing a substrate with pure water ,
A treatment tank having an opening at the top and storing pure water ;
Substrate holding means for holding the substrate in the processing tank;
Discharge port provided above the processing bath, and pure water discharging means for discharging the pure water like a shower from the discharge port toward the surface of the substrate in the processing bath,
A supply port is provided at a lower portion in the treatment tank, and pure water supply means for supplying pure water from the supply port to the treatment tank and storing the pure water in the treatment tank;
A discharge port is provided at the bottom of the treatment tank, and drainage means for discharging flush water in the treatment tank through the discharge port;
A lid member that covers the upper opening of the treatment tank so as to be freely opened and closed;
An inert gas supply means for supplying an inert gas to the surface of the rinsing water in the treatment tank;
Discharge of pure water on the substrate surface in the processing bath by the pure water discharge means, discharge of washing water from the drainage means according to the processing bath, the pure water into the processing bath by the pure water supply means Supply, the cover with the lid member covering the upper opening of the treatment tank to which pure water is supplied by the pure water supply means, and the process with the upper opening covered by the lid member with the inert gas supply means Control means for controlling the supply of inert gas to the flush water level in the tank,
A specific resistance meter for measuring the specific resistance value of the washing water in the treatment tank;
Equipped with a,
Based on the specific resistance value measured by the specific resistance meter, the control means supplies pure water into the treatment tank by the pure water supply means and flush water in the treatment tank by the inert gas supply means. Each of the supply of the inert gas to the liquid surface is stopped, the lid member is opened, and control is performed so as to finish the substrate cleaning process with pure water,
Discharge of pure water onto the substrate surface in the treatment tank by the pure water discharge means and discharge of flush water from the treatment tank by the drain means are alternately repeated a plurality of times, and the inside of the treatment tank by the drain means After the final flush water discharge from the end, supply of pure water into the treatment tank by the pure water supply means, a cover for the upper opening of the treatment tank by the lid member, and the inert gas supply means The substrate processing apparatus controlled by the control means so as to start the supply of the inert gas to the washing water level in the processing tank . The substrate processing apparatus according to claim 1, wherein a gas supply port of the inert gas supply means is provided in the lid member.

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