JP5107762B2 - Substrate processing equipment - Google Patents

Description

  The present invention is a method of immersing various substrates such as semiconductor wafers, glass substrates for liquid crystal display devices, glass substrates for plasma display (PDP), glass / ceramic substrates for magnetic / optical disks, electronic device substrates, etc. The present invention relates to a substrate processing apparatus that performs processing such as etching.

  In a substrate processing apparatus that performs processing such as cleaning and etching by immersing a substrate such as a semiconductor device in a processing solution stored in a processing tank, the substrate holder holds a plurality of substrates, and the substrate holder Is moved vertically between the inside of the processing tank and the upper position of the processing tank, and a substrate holder is inserted into the processing tank through the upper surface opening in a state where a plurality of substrates are held. The substrate is immersed in the processing solution. The substrate holders are respectively provided on the left and right sides of the first holding portion extending horizontally and the first holding portion so that the plurality of substrates can be held in a vertical posture. The second holding portion and the third holding portion that extend in the horizontal direction in parallel with each other. Each holding portion is formed with a plurality of substrate holding grooves that engage with the peripheral edge of the substrate. And, the first holding part supports the lowermost end part of each substrate, respectively, the second holding part and the third holding part respectively support the lower end parts of the left and right sides of each board with respect to the lowermost end part, A plurality of substrates are arranged and held in the horizontal direction at a slight interval in parallel with each other.

In the vicinity of the bottom of the processing tank, a pair of discharge pipes are disposed on both the left and right sides so as to extend along the arrangement direction of the plurality of substrates held by the substrate holder. The discharge pipe is formed with a plurality of slit-shaped discharge ports arranged in a straight line along the axial direction. The discharge port of the discharge pipe opens toward the inside center of the processing tank and obliquely downward. The discharge pipe is connected to a processing liquid supply source of pure water or chemical liquid through a processing liquid supply pipe. Then, when the processing liquid is continuously supplied from the processing liquid supply source to the discharge pipe, the processing liquid is discharged from the discharge port of the discharge pipe into the processing tank, and the processing tank is filled with the processing liquid. The processing liquid overflows from the upper end of the nozzle. For example, when washing a substrate with water, fill the inside of the processing tank with pure water and let the processing liquid overflow from the upper end of the processing tank, and insert a substrate holder holding multiple substrates into the processing tank. Then, the substrate is immersed in pure water in the treatment tank. At this time, the pure water discharged obliquely downward from the discharge ports of the pair of left and right discharge pipes toward the central direction inside the treatment tank collides near the bottom center of the treatment tank and flows upward. The direction is changed to flow upward in the processing tank as an upward flow, and overflow from the upper end of the processing tank. As such pure water rises and overflows, unnecessary substances such as particles on the substrate surface and residual chemicals are discharged out of the treatment tank (see, for example, Patent Document 1).
JP 2000-114217 A (page 4-5, FIGS. 3 and 4)

  In the substrate processing apparatus described above, in order to remove residual chemicals or particles from the surface of the substrate, it is necessary to flow pure water through the gap between the substrate at a relatively high flow rate. For this reason, in the conventional processing apparatus, eddy currents or the like are generated in the processing tank, and the flow of pure water in the processing tank is always in a turbulent state, and particles and the like are efficiently discharged out of the processing tank. There was something I couldn't do. In addition, since the inside of the treatment tank is always in a turbulent state, the surface of pure water in the treatment tank undulates, and carbon dioxide in the air is easily taken into the pure water through the liquid surface. In some cases, the recovery of the specific resistance value, which is a measure of the pure water content, was delayed. As a result, there are problems such as a long processing time and an increase in the amount of pure water used.

  This invention is made in view of the above circumstances, in a substrate processing apparatus for processing a substrate by holding a plurality of substrates by a substrate holding means and immersing them in a processing liquid in a processing tank. Remove unnecessary substances such as particles and residual chemicals from the surface of the substrate and efficiently discharge them to the outside of the treatment tank, and suppress the intake of carbon dioxide in the air into the treatment liquid in the treatment tank An object of the present invention is to provide a substrate processing apparatus that can reduce the processing time and the amount of processing liquid used.

According to a first aspect of the present invention, in a substrate processing apparatus for processing a substrate with a processing liquid, the processing tank for opening the upper surface and storing the processing liquid is arranged in parallel with each other in a vertical posture and horizontally. A first holding unit for holding the lowermost ends of the plurality of substrates; and a second holding unit and a third holding unit for holding the lower ends of the plurality of substrates on both sides with respect to the lowermost ends. A substrate holding means that moves up and down between an inner position of the processing tank and an upper position of the processing tank in a state where a plurality of substrates are held by the holding sections, respectively, and held by the substrate holding means A pair of processing liquid supply means that are respectively disposed along the arrangement direction of the plurality of substrates and discharge the processing liquid from the respective discharge ports provided in the vicinity of the bottom of the processing tank toward the inside of the processing tank. If, savings in the processing bath A specific resistance measuring means for measuring the specific resistance of the treating solution, the specific resistance value of the processing solution to be measured by the resistivity measurement means until the rise to a predetermined value, holding a plurality of substrates In the processing tank, the substrate holding means is alternately repeated between a position where the second holding portion and the third holding portion hit the processing liquid from each discharge port of the pair of processing liquid supply means and a position where they do not hit. When the specific resistance value of the processing liquid becomes equal to or greater than a predetermined value, the substrate holding unit is held at a position where the second holding unit and the third holding unit hit the processing liquid from each discharge port of the pair of processing liquid supply units. And a movement control means for stopping the means .

According to a second aspect of the present invention, in the substrate processing apparatus according to the first aspect, the processing performed on the substrate is a rinsing process using pure water, and the pair of processing liquid supply means is provided from each discharge port. The specific resistance value measuring means is a specific resistance meter that measures the specific resistance value of the pure water stored in the treatment tank .

In the substrate processing apparatus according to the first aspect of the present invention, the substrate holding means holding a plurality of substrates by the movement control means is configured such that the second holding portion and the third holding portion are each discharge port of the pair of processing liquid supply means. since it is the treatment liquid and a position which does not touch a position corresponding moving to repeat alternately from, when the second holding unit and the third holding portion is a substrate holding means in a position not exposed to the treatment solution is a conventional device Similarly, the processing liquid discharged from each discharge port of the processing liquid supply means flows through the gap between the substrates at a relatively high flow rate. For this reason, residual chemicals and particles are reliably removed from the surface of the substrate. On the other hand, when the substrate holding unit is in a position where the second holding unit and the third holding unit hit the processing liquid, the processing liquid discharged from each discharge port of the processing liquid supply unit hits the second holding unit and the third holding unit. The flow is diffused to reduce the flow velocity, and flows upward through the gap between the substrates at a relatively small flow velocity. For this reason, the processing liquid does not become a turbulent flow state between the substrates and flows relatively slowly toward the upper part of the processing tank, and overflows from the upper end of the processing tank. And the particles etc. which exist in the processing liquid in a processing tank are efficiently discharged | emitted out of a processing tank by an upward flow and an overflow. Further, since the flow of the treatment liquid in the treatment tank does not become a turbulent state, it is possible to suppress the liquid level of the treatment liquid in the treatment tank from being swollen and carbon dioxide in the air being taken into the treatment liquid. .
Then, until the specific resistance value of the processing liquid measured by the specific resistance value measuring unit rises to a predetermined value, the second holding unit and the third holding unit hit the processing liquid from each discharge port of the processing liquid supply unit. When the substrate holding means is moved so as to alternately repeat the position and the non-contact position, and the specific resistance value of the processing liquid becomes a predetermined value or more, that is, if the processing liquid is pure water, for example, When the water level is restored, the substrate holding unit is stopped at a position where the second holding unit and the third holding unit hit the processing liquid from each discharge port of the processing liquid supply unit. Discharge is promoted, and the liquid level of the treatment liquid in the treatment tank undulates and carbon dioxide in the air is prevented from being taken into the treatment liquid. For this reason, the state of increasing the flow rate of the processing liquid for removing particles or the like from the substrate surface is not repeated more than necessary.
Therefore, when the substrate processing apparatus of the invention according to claim 1 is used, the processing time can be shortened and the amount of processing liquid used can be reduced.

In the substrate processing apparatus according to the second aspect of the present invention, the residual chemical solution or particles are reliably removed from the surface of the substrate by the fast flow of pure water. On the other hand, when the pure water level in the treatment tank is restored, particles etc. existing in the pure water in the treatment tank are efficiently discharged out of the treatment tank by the gentle flow of pure water. It is possible to prevent the water level from rippled and carbon dioxide in the air from being taken into the pure water. Therefore, the substrate is preferably washed with water.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best embodiment of the present invention will be described with reference to the drawings.
1 and 2 are schematic cross-sectional views showing a schematic configuration of a substrate processing apparatus according to an example of an embodiment of the present invention.

  The substrate processing apparatus includes a processing tank 10 having an upper surface opened and storing a processing solution, and a substrate holder (lifter) 12 that holds a plurality of substrates W such as semiconductor wafers. The substrate holder 12 inserts the substrate W into the processing tank 10 to immerse the substrate W in the processing liquid in the processing tank 10, and also pulls up the substrate W from the processing liquid in the processing tank 10 to perform processing. The substrate W is discharged to a position above the tank 10.

  A liquid receiving part 14 into which the processing liquid overflowing from the upper end port of the processing tank 10 flows is provided on the outer periphery of the upper part of the processing tank 10, and is discharged to a drain port formed at the bottom of the liquid receiving part 14. The liquid pipe 16 is in communication. A pair of discharge pipes 18 and 18 are provided on the left and right sides of the lower portion of the processing tank 10. Each discharge pipe 18 is disposed so as to extend along the arrangement direction of the plurality of substrates W held by the substrate holder 12 (in a direction perpendicular to the paper surface). The discharge pipe 18 is provided with a discharge port near the bottom of the processing tank 10. The discharge ports are formed along the axial direction of the discharge pipe 18, and for example, a plurality of slit-shaped discharge ports are formed on a straight line. The discharge port of the discharge pipe 18 opens toward the inside center of the processing tank 10 and obliquely downward.

  A processing liquid supply pipe 20 is connected to each discharge pipe 18 in communication therewith. The processing liquid supply pipe 20 is connected to the outlet side of the mixing valve 22. A pure water supply pipe 24 connected to a pure water supply source is connected to the inlet of the mixing valve 22, and an open / close control valve 26 is inserted in the pure water supply pipe 24. The mixing valve 22 is connected to a chemical liquid supply pipe 28 connected to a chemical liquid supply source such as hydrofluoric acid (HF), and an open / close control valve 30 is inserted in the chemical liquid supply pipe 28. . When the open / close control valve 26 provided in the pure water supply pipe 24 is opened and the open / close control valve 30 provided in the chemical liquid supply pipe 28 is closed, the processing liquid supply pipe 20 passes through the outlet of the mixing valve 22. Pure water is supplied to the discharge pipe 18, and pure water is discharged obliquely downward from the discharge port of the discharge pipe 18 toward the center in the treatment tank 10. Further, in a state where both of the open / close control valves 26 and 30 are opened, hydrofluoric acid mixed with pure water by the mixing valve 22 and diluted to a predetermined concentration is supplied from the outlet of the mixing valve 22 to the treatment liquid. It is supplied to the discharge pipe 18 through the supply pipe 20, and hydrofluoric acid is discharged obliquely downward from the discharge port of the discharge pipe 18 toward the center in the processing tank 10.

  The substrate holder 12 includes a lifter portion 32 arranged in the vertical direction, and three holding portions respectively attached to the lower end portion of the lifter portion 32 and arranged in parallel to each other in the horizontal direction, that is, The first holding portion 34 attached to the center of the lower end portion of the lifter portion 32, and the second holding portion 36a and the third holding portion 36b attached to the left and right of the lower end portion of the lifter portion 32 are provided. is doing. Each holding portion 34, 36 a, 36 b is formed with a plurality of substrate holding grooves (not shown) that engage with the peripheral edge of the substrate W. Each of the plurality of substrates W is supported at the lowermost end thereof by the first holding portion 34, and the lower end portions on both sides of the lowermost end portion are the second holding portion 36a and the third holding portion 36b. And are arranged and held in the horizontal direction on the substrate holder 12 in a vertical posture at a slight interval in parallel with each other.

  The substrate holder 12 has a lifter portion 32 supported by a support mechanism (not shown), and a lifter driving device 38 (not shown in detail) between the inside of the processing tank 10 and an upper position of the processing tank 10. It can be reciprocated in the vertical direction. The raising / lowering operation of the substrate holder 12 by the lifter driving device 38 is controlled by the controller 40. Further, by controlling the lifter driving device 38 with the controller 40, the substrate holder 12 holding the plurality of substrates W is reciprocated in the processing tank 10 by a predetermined distance in the vertical direction. That is, as shown in FIG. 1, the second holding part 36a and the third holding part 36b do not hit the processing liquid discharged from the discharge ports of the pair of discharge pipes 18, 18, and the pair as shown in FIG. The substrate holder 12 is moved by the lifter driving device 38 to a position where the second holding part 36a and the third holding part 36b hit the processing liquid discharged from the discharge ports of the discharge pipes 18 and 18, respectively.

  Further, a resistivity meter sensor 42 for measuring the resistivity value of the treatment liquid stored in the treatment vessel 10, for example, pure water, is installed inside the treatment vessel 10, and the sensor 42 is connected to the monitor 44. Has been. The specific resistance meter monitor 44 is connected to the controller 40, and a control signal is sent from the controller 40 to the lifter driving device 38 based on a specific resistance value detection signal sent from the monitor 44 to the controller 40. The movement of the substrate holder 12 in the tank 10 in the vertical direction is controlled.

Next, an example of substrate processing using the substrate processing apparatus having the above-described configuration will be described.
First, pure water is continuously discharged from the discharge port of the discharge pipe 18 into the processing tank 10, the inside of the processing tank 10 is filled with pure water, and pure water is supplied from the upper end port of the processing tank 10 to the liquid receiving unit 14. It is said that it overflows. In this state, the substrate holder 12 holding the plurality of substrates W descends from the upper position of the processing tank 10, and the plurality of substrates W held by the substrate holder 12 as shown in FIG. The substrate W is inserted into the processing tank 10 and immersed in pure water in the processing tank 10, and the substrate W is washed with pure water. After washing with water, hydrofluoric acid adjusted to a predetermined concentration by mixing hydrofluoric acid into pure water by the mixing valve 22 is continuously discharged from the discharge port of the discharge pipe 18 into the treatment tank 10. This hydrofluoric acid pushes pure water from the upper end port of the treatment tank 10, the inside of the treatment tank 10 is replaced with hydrofluoric acid, the inside of the treatment tank 10 is filled with hydrofluoric acid, and liquid is received from the upper end port of the treatment tank 10. The hydrofluoric acid overflows into the portion 14. Then, the substrate W is cleaned or etched with hydrofluoric acid filled in the processing tank 10. At this time, after injecting hydrofluoric acid into the processing tank 10 for a predetermined time, the supply of hydrofluoric acid to the processing tank 10 is stopped, and this state is maintained for a predetermined time, and the substrate is placed in the hydrofluoric acid in the processing tank 10. W may be immersed.

When the treatment with hydrofluoric acid is completed, pure water is continuously discharged from the discharge port of the discharge pipe 18 into the treatment tank 10 again. The pure water pushes out hydrofluoric acid from the upper end of the treatment tank 10 and replaces the inside of the treatment tank 10 with pure water. Then, the inside of the processing tank 10 is filled with pure water, and the pure water overflows from the upper end port of the processing tank 10 to the liquid receiving portion 14, and the substrate W is washed with water. At this time, the substrate holder 12 holding the substrate W several sheets double, the position where the second holding portion 36a and the third holding portion 36b hits the deionized water from the respective discharge ports of the pair of the discharge pipe 18 (FIG. 2 The position shown in FIG. 1 and the position not shown (position shown in FIG. 1) are alternately moved so as to repeat every predetermined time, for example, every 8 seconds.

  As described above, by changing the vertical position of the substrate holder 12 and washing the substrate W with water, the second holding portion 36a and the third holding portion 36b are connected to the pair of discharge pipes 18 and 18, as shown in FIG. When the substrate holder 12 is located at a position that does not contact the pure water discharged from each discharge port, the pure water discharged from each discharge port of the pair of discharge pipes 18 and 18 flows into the substrate W at a relatively high flow rate. It flows through the gap with the substrate W. For this reason, residual hydrofluoric acid and particles are reliably removed from the surface of the substrate W. On the other hand, when the substrate holder 12 is located at a position where the second holding part 36a and the third holding part 36b hit the pure water from the discharge ports of the pair of discharge pipes 18 and 18, as shown in FIG. The pure water discharged from each discharge port of the discharge pipes 18 and 18 hits the second holding part 36a and the third holding part 36b, the flow is diffused and the flow velocity is weakened. It flows upward through the gap. For this reason, the pure water does not enter a turbulent flow state between the substrate W and the substrate W, flows relatively slowly toward the upper part of the processing tank 10, and overflows from the upper end port of the processing tank 10. And the particles etc. which exist in the pure water in the processing tank 10 will be efficiently discharged | emitted out of the processing tank 10 by an upward flow and an overflow. Moreover, since the flow of pure water in the treatment tank 10 does not become a turbulent state, the level of pure water in the treatment tank 10 undulates and carbon dioxide in the air is taken into the pure water. It can be suppressed.

Their to, in this case, the resistivity of the pure water stored in the processing bath 10 is measured with a resistivity meter 42 and 44, the lifter driven by the controller 40 on the basis of the resistivity of the pure water that is the measured Until the measured value of the specific resistance rises to a predetermined value by controlling the apparatus 38, that is, until the pure water level in the treatment tank 10 is recovered, for example, the specific resistance value of pure water in the treatment tank 10 is 5 MΩ · The substrate holder 12 is repeatedly placed so that the position where the second holding part 36a and the third holding part 36b are in contact with the pure water from the discharge ports of the pair of discharge pipes 18 and the position where they are not in contact with each other until the distance becomes cm. When the specific resistance value of the pure water in the treatment tank 10 is equal to or greater than a predetermined value, the second holding unit 36a and the third holding unit 36b hit the pure water from the discharge ports of the pair of discharge pipes 18 and 18. to stop the substrate holder 12 in position. FIG. 3 (a) shows an example of a time chart of the movement operation of the substrate holder 12 in the vertical direction, and FIG. 3 (b) shows the temporal change in the specific resistance value of pure water at that time. An example is shown. When the washing of the substrate W is completed, the substrate holder 12 is raised, the substrate W is discharged from the processing tank 10, and the substrate W is dried.

  In the above-described embodiment, the substrate holder 12 is moved in the vertical direction in the treatment tank 10 only during the final water washing process. However, the first water washing process or cleaning with hydrofluoric acid (or etching) is performed. Even during processing, the substrate holder 12 may be moved in the vertical direction in the processing tank 10.

1 is a schematic cross-sectional view illustrating a schematic configuration of a substrate processing apparatus according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing a state in which the substrate holder that is a component of the substrate processing apparatus shown in FIG. 1 has moved downward from the state shown in FIG. It is a figure for demonstrating one example of the process of the board | substrate using the substrate processing apparatus shown in FIG.1 and FIG.2, (a) shows the time chart of the movement operation | movement of a substrate holder to an up-down direction. , (B) shows the temporal change in the specific resistance value of pure water.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Processing tank 12 Substrate holder 14 Liquid receiving part 18 Discharge pipe 20 Processing liquid supply pipe 22 Mixing valve 24 Pure water supply pipe 26, 30 Opening / closing control valve 28 Chemical liquid supply pipe 32 Lifter part of substrate holder 34 First holding part 36a 36b Second holding unit and third holding unit 38 Lifter driving device 40 Controller 42 Sensor of resistivity meter 44 Monitor of resistivity meter W substrate

Claims (2)

In a substrate processing apparatus for processing a substrate with a processing liquid,
A treatment tank in which the upper surface is opened and the treatment liquid is stored;
A first holding unit that holds the lowermost ends of the plurality of substrates arranged in parallel and horizontally in a vertical posture, and lower end portions on both sides of the lowermost ends of the plurality of substrates, respectively. It has the 2nd holding part and the 3rd holding part to hold, and is in the up-and-down direction between the inward position of the processing tub, and the upper position of the processing tub in the state where a plurality of substrates were held by each holding part, respectively. Moving substrate holding means;
Disposed along the arrangement direction of the plurality of substrates held by the substrate holding means, and discharges the processing liquid from the discharge ports respectively provided near the bottom of the processing tank toward the inside of the processing tank. A pair of processing liquid supply means,
Specific resistance value measuring means for measuring the specific resistance value of the processing liquid stored in the processing tank;
Until the specific resistance value of the processing liquid measured by the specific resistance value measuring means rises to a predetermined value, the substrate holding means holding a plurality of substrates is placed in the processing tank in the second holding portion and the second 3 When the holding unit is moved so as to alternately repeat the position where it hits the processing liquid from each discharge port of the pair of processing liquid supply means and the position where it does not hit , when the specific resistance value of the processing liquid becomes a predetermined value or more, A movement control unit that stops the substrate holding unit at a position where the second holding unit and the third holding unit hit the processing liquid from each discharge port of the pair of processing liquid supply units ;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
The treatment performed on the substrate is a water washing treatment with pure water, wherein the pair of treatment liquid supply means discharges pure water from each discharge port, and the specific resistance value measurement means is provided in the treatment tank. A substrate processing apparatus, which is a resistivity meter for measuring a resistivity value of stored pure water .

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