JP5016430B2 - Substrate processing equipment - Google Patents

Description

  The present invention relates to a substrate processing apparatus for performing processing such as cleaning and etching on a substrate by immersing a substrate such as a semiconductor substrate, a glass substrate for a liquid crystal display device, or a glass substrate for a photomask in a processing solution.

  In a substrate manufacturing process, a substrate processing apparatus is used that processes a substrate by immersing the substrate in a processing solution stored in a processing tank. FIG. 10 is a diagram illustrating an example of a conventional substrate processing apparatus 100. As shown in FIG. 10, the conventional substrate processing apparatus 100 includes a processing tank 110 that stores a processing liquid, and the processing tank 110 discharges the processing liquid from a discharge nozzle 113 arranged at the bottom of the processing tank 110. The processing liquid is supplied to the periphery of the substrate W by overflowing the processing liquid from the top of the substrate W, and the substrate W is processed.

  The configuration of such a conventional substrate processing apparatus is disclosed in Patent Document 1, for example.

JP 2007-36189 A

  As shown in FIG. 10, the discharge nozzle 113 of the conventional substrate processing apparatus 100 discharges the processing liquid toward the substrate W in the processing tank 110. For this reason, the processing liquid discharged from the discharge nozzle 113 forms a relatively high-speed liquid flow inside the processing tank 110 and is stirred throughout the processing tank 110. However, since such a conventional discharge form stirs the processing liquid in the entire interior of the processing tank 110, the old processing liquid cannot be efficiently discharged from the processing tank 110 and replaced with a new processing liquid. It was.

  In such a conventional substrate processing apparatus 100, when foreign substances such as particles are mixed in the processing tank 110, the foreign substances are also stirred together with the processing liquid in the processing tank 110. For this reason, the conventional substrate processing apparatus 100 cannot quickly discharge the foreign matter mixed in the processing tank 110 from the processing tank 110. Therefore, such foreign matter may adhere to the surface of the substrate W being processed, contaminating the substrate W, or causing a processing failure of the substrate W. In particular, when an acidic chemical solution is used as the processing liquid or when a hydrophobic surface substrate W is used, foreign matters such as particles are likely to adhere to the surface of the substrate W, and thus the above problem is more serious. .

  The present invention has been made in view of such circumstances, and provides a substrate processing apparatus capable of suppressing the stirring of the processing liquid inside the processing tank and efficiently discharging foreign matters such as particles to the outside of the processing tank. The purpose is to provide.

In order to solve the above-mentioned problem, the invention according to claim 1 is a substrate processing apparatus for processing a substrate by immersing the substrate in a processing solution, and has a side wall and a bottom wall, and the processing is performed inside the substrate processing apparatus. A processing tank for storing the liquid, a discharge means for discharging the processing liquid into the processing tank, a discharging means for discharging the processing liquid overflowing from the upper part of the processing tank, the inside of the processing tank, and the processing tank Moving means for moving the substrate up and down between the upper position and the discharge means, the discharge means having a pair of discharge nozzles , the pair of discharge nozzles facing the processing tank inside the processing tank Each of the pair of side walls is formed so that a part of the pair of side walls protrudes outwards by discharging the processing liquid toward the recesses formed on the pair of side walls. It is characterized by that.

The invention according to claim 2 is a substrate processing apparatus according to claim 1, wherein the recess is characterized by being formed respectively on the lower ends of the pair of side walls.

A third aspect of the present invention is the substrate processing apparatus according to the first or second aspect , wherein the concave portion is a groove having a V-shaped cross section that opens toward the inside of the processing tank. And

The invention according to claim 4 is the substrate processing apparatus according to claim 3 , wherein the discharge nozzle is directed toward a lower tapered surface among a pair of tapered surfaces forming the groove having the V-shaped cross section. The treatment liquid is discharged.

The invention according to claim 5 is the substrate processing apparatus according to claim 1 or 2 , wherein the concave portion is a curved groove opened toward the inside of the processing tank. .

According to invention of Claims 1-5 , the discharge means of a substrate processing apparatus discharges a process liquid toward a side wall inside a processing tank. For this reason, the processing liquid discharged from the discharging means collides with the side wall and diffuses, and proceeds toward the upper part of the processing tank as a low-speed and uniform liquid flow. Accordingly, foreign matters such as particles generated inside the processing tank rise to the upper part of the processing tank without being stirred inside the processing tank, and are quickly discharged to the outside of the processing tank together with the processing liquid. In addition, since it is not necessary to complicate the structure of the ejection unit itself, the manufacturing cost of the substrate processing apparatus can be reduced.

In addition, according to the first to fifth aspects of the present invention, the discharge means discharges the processing liquid toward the recess formed in the side wall . For this reason, the process liquid diffused in the side wall can be advanced toward the center of the process tank. Therefore, it is possible to satisfactorily form a low-speed and uniform process liquid flow around the substrate immersed in the process liquid.

In addition, according to the inventions described in claims 1 to 5 , the discharge means has a pair of discharge nozzles, and the pair of discharge nozzles are respectively directed toward the recesses formed in the pair of opposing side walls of the treatment tank. Discharge the processing liquid. For this reason, the processing liquid diffused in the pair of side walls can be merged in the vicinity of the central portion of the processing tank, and can be advanced toward the upper part in the vicinity of the central portion of the processing tank.

In particular, according to the second aspect of the present invention, the recesses are respectively formed at the lower ends of the pair of side walls. For this reason, the processing liquid can be diffused in the vicinity of the bottom of the processing tank, and the flow of the processing liquid from the bottom to the top of the processing tank can be well formed.

In particular, according to the third aspect of the present invention, the recess is a groove having a V-shaped cross section that opens toward the inside of the treatment tank. For this reason, a recessed part can be easily formed in the side wall of a processing tank. Further, the traveling direction of the processing liquid can be easily set by the inclination of the tapered surface forming the groove having the V-shaped cross section.

In particular, according to the fourth aspect of the invention, the discharge nozzle discharges the processing liquid toward the lower tapered surface of the pair of tapered surfaces forming the groove having a V-shaped cross section. For this reason, more process liquid can be advanced toward the bottom part vicinity of a processing tank.

In particular, according to the invention described in claim 5 , the concave portion is a curved groove opened toward the inside of the treatment tank. For this reason, the advancing direction of a process liquid can be set more appropriately.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

<1. Configuration of substrate processing apparatus>
FIG. 1 is a longitudinal sectional view of a substrate processing apparatus 1 according to an embodiment of the present invention, cut along a plane parallel to the main surface of a substrate W. FIG. 1 also shows the configuration of the control system and the supply / drainage system of the substrate processing apparatus 1. FIG. 2 is a longitudinal sectional view of the substrate processing apparatus 1 cut along a plane perpendicular to the main surface of the substrate W. FIGS. 1 and 2 show a common XYZ orthogonal coordinate system in order to clarify the positional relationship of each part in the apparatus.

  The substrate processing apparatus 1 stores a hydrofluoric acid (HF) solution in a processing tank 10 and immerses a plurality of substrates (hereinafter simply referred to as “substrates”) W in the stored hydrofluoric acid solution. , An apparatus for performing an etching process on the substrate W. As shown in FIGS. 1 and 2, the substrate processing apparatus 1 mainly includes a processing tank 10 for storing a hydrofluoric acid solution, a lifter 20 that holds the substrate W up and down, and a processing tank 10. A hydrofluoric acid solution supply unit 30 for supplying a hydrofluoric acid solution, a hydrofluoric acid solution discharge unit 40 for discharging the hydrofluoric acid solution from the treatment tank 10, and a control unit 50 for controlling the operation of each unit in the apparatus. And.

  The processing tank 10 is a storage container made of a chemical resistant material such as quartz. The processing tank 10 has an inner tank 11 for storing a hydrofluoric acid solution and immersing the substrate W therein, and an outer tank 12 formed on the outer peripheral portion of the inner tank 11. The inner tank 11 has a bottom wall 111 located below the substrate W in a state in which the substrate W is immersed, and side walls 112a to 112d located on the sides of the substrate W. It is open. A pair of discharge nozzles 13 for discharging a hydrofluoric acid solution is provided inside the inner tank 11. When the hydrofluoric acid solution is discharged from the discharge nozzle 13, the hydrofluoric acid solution is stored in the inner tank 11, and the hydrofluoric acid solution stored up to the upper part of the inner tank 11 is transferred from the upper part of the inner tank 11 to the outer tank 12. Overflow.

  Of the side walls 112a to 112d of the inner tub 11, the pair of side walls 112a and 112b parallel to the arrangement direction of the substrates W has a shape in which a lower end portion thereof (a portion in contact with the bottom wall 111) protrudes outward. is doing. For this reason, the groove part 14 extended along the arrangement direction of the board | substrate W is formed in the inner surface of the lower end part of the side walls 112a and 112b. Each of the groove portions 14 has an upper tapered surface 14a and a lower tapered surface 14b, and constitutes a groove having a V-shaped cross section that opens toward the inside of the inner tank 11 as a whole.

  The pair of discharge nozzles 13 are tubular members arranged horizontally along the direction of arrangement of the grooves 14 formed in the side walls 112a and 112b and the substrate W. Each discharge nozzle 13 has a plurality of discharge ports 13a formed at equal intervals. The positions of the plurality of discharge ports 13 a on the discharge nozzle 13 are positions corresponding to the outside of the substrates W arranged between the adjacent substrates W and both ends in the processing tank 10. Further, the discharge direction of the plurality of discharge ports 13 a is directed to the lower tapered surface 14 b of the groove portion 14. The hydrofluoric acid solution discharged from the plurality of discharge ports 13 a collides perpendicularly with the lower tapered surface 14 b of the groove 14.

  FIG. 3 is a diagram illustrating the flow of the hydrofluoric acid solution when the hydrofluoric acid solution is further discharged from the discharge nozzle 13 in a state where the hydrofluoric acid solution is stored in the treatment tank 10. As shown in FIG. 3, the hydrofluoric acid solution discharged from the discharge nozzle 13 collides with the lower taper surface 14b of the groove 14 and changes the direction toward the inside of the inner tank 11 while diffusing along the lower taper surface 14b. And proceed. The hydrofluoric acid solution collides with the lower taper surface 14b and diffuses to slow down the flow, and further rises slowly from the vicinity of the bottom of the inner tank 11 in the upward direction. As described above, the groove portion 14 formed on the side walls 112a and 112b serves as a rectifying means for directing the flow direction of the hydrofluoric acid solution to the inside of the inner tank 11, and diffuses the hydrofluoric acid solution to flow the flow. Plays the role of slowing down.

  The lifter 20 is a transport mechanism for moving the substrate W up and down between the inside of the processing tank 10 and an upper position of the processing tank 10 while holding the substrate W. The lifter 20 has three holding bars 21 extending in the arrangement direction of the substrates W, and each holding bar 21 is provided with a plurality of holding grooves 21a. The board | substrate W is hold | maintained in the standing attitude | position in parallel with each other on the three holding | maintenance rods 21 in the state which fitted the peripheral part to the holding groove 21a. The lifter 20 is connected to a drive unit 22 configured by a known mechanism in which a motor, a ball screw, or the like is combined. When the drive unit 22 is operated, the lifter 20 moves up and down, and the substrate W is transported between the immersion position (the state shown in FIG. 1) inside the processing tank 10 and the lifting position above the processing tank 10. .

  The hydrofluoric acid solution supply unit 30 is a piping system for supplying the treatment liquid to the discharge nozzle 13. As shown in FIG. 1, the hydrofluoric acid solution supply unit 30 includes a hydrofluoric acid solution supply source 31, a pipe 32, and an on-off valve 33. The upstream end of the pipe 32 is connected to a hydrofluoric acid solution supply source 31, and an open / close valve 33 is inserted in the course of the pipe 32. Further, the downstream side of the pipe 32 is branched into two and connected to the pair of discharge nozzles 13 respectively. For this reason, when the on-off valve 33 is opened, the hydrofluoric acid solution is supplied from the hydrofluoric acid solution supply source 31 through the pipe 32 to the pair of discharge nozzles 13, and the inside of the inner tank 11 from the plurality of discharge ports 13 a of the discharge nozzle 13. A hydrofluoric acid solution is discharged.

  The hydrofluoric acid solution discharge unit 40 is a piping system for recovering the hydrofluoric acid solution from the outer tank 12 and discharging the recovered hydrofluoric acid solution to the drainage line. As shown in FIG. 1, the hydrofluoric acid solution discharge unit 40 includes a pipe 41 and an on-off valve 42. The upstream end of the pipe 41 is connected to the outer tub 12, and the downstream end of the pipe 41 is connected to a drain line in the factory. In addition, an on-off valve 42 is inserted in the middle of the pipe 41. For this reason, when the on-off valve 42 is opened, the hydrofluoric acid solution is discharged from the outer tank 12 through the pipe 41 to the drain line.

  The control unit 50 is a computer device for controlling the operation of each unit of the substrate processing apparatus 1. The control unit 50 is electrically connected to the drive unit 22, the on-off valve 33, and the on-off valve 42 described above. The control unit 50 advances the processing of the substrate W by operating the driving unit 22, the on-off valve 33, and the on-off valve 42 according to a program installed in advance and various instruction inputs.

<2. Operation of substrate processing apparatus>
Subsequently, an operation when the substrate W is processed in the substrate processing apparatus 1 will be described with reference to a flowchart of FIG. When processing the substrate W in the substrate processing apparatus 1, first, the on-off valve 33 and the on-off valve 42 are opened. Thus, the hydrofluoric acid solution is supplied from the hydrofluoric acid solution supply source 31 to the discharge nozzle 13 via the pipe 32, and the hydrofluoric acid solution is discharged from the discharge nozzle 13 into the inner tank 11 (step S1). The hydrofluoric acid solution discharged from the discharge nozzle 13 is gradually stored inside the inner tank 11 and eventually overflows from the upper part of the inner tank 11 to the outer tank 12.

  Next, the substrate W transported from another apparatus by a predetermined transport mechanism is placed on the lifter 20 that stands by at a position above the processing bath 10. When the substrate W is placed on the lifter 20, the substrate processing apparatus 1 operates the driving unit 22 to lower the lifter 20 and immerses the substrate W in the hydrofluoric acid solution stored in the processing tank 10. (Step S2). When the substrate W is immersed in the hydrofluoric acid solution, the substrate W is subjected to an etching process by the hydrofluoric acid component in the hydrofluoric acid solution.

  At this time, the flow of the hydrofluoric acid solution as shown in FIG. That is, the hydrofluoric acid solution discharged from the discharge nozzle 13 collides with the lower taper surface 14b of the groove 14 and travels in the direction of the substrate W along the lower taper surface 14b while diffusing and slowing down. Then, the hydrofluoric acid solution merged in the vicinity of the center bottom of the inner tank 11 slowly rises from the vicinity of the bottom of the inner tank 11 toward the upper part, and forms a liquid flow that moves downward and uniformly upward around the substrate W. .

  As the etching process proceeds, metal components are eluted from the surface of the substrate W into the hydrofluoric acid solution, and foreign matters such as particles adhering to the surface of the substrate W are lifted off (released) and mixed into the hydrofluoric acid solution. To do. However, as described above, a liquid flow is formed around the substrate W at a low speed and uniformly upward. For this reason, the metal component and the foreign matter mixed in the hydrofluoric acid solution float up toward the upper portion of the inner tank 11 without being stirred inside the inner tank 11, and are quickly discharged to the outer tank 12 together with the hydrofluoric acid solution. The Therefore, it is possible to prevent the metal component and foreign matter generated in the hydrofluoric acid solution from reattaching to the surface of the substrate W.

  When the etching process for a predetermined time is completed, the substrate processing apparatus 1 operates the drive unit 22 to raise the lifter 20, and pulls up the substrate W from the hydrofluoric acid solution stored in the inner tank 11 (step S3). . Thereafter, the substrate W is transferred from the lifter 20 to a predetermined transport device and transported to a device that performs subsequent processing. Further, the substrate processing apparatus 1 closes the on-off valve 33 and the on-off valve 42. Thereby, the discharge of the hydrofluoric acid solution from the discharge nozzle 13 and the discharge of the hydrofluoric acid solution to the hydrofluoric acid solution discharge unit 40 are stopped (step S4). With the above, a series of processes for one set of substrates W is completed.

  As described above, the substrate processing apparatus 1 of the present embodiment discharges the hydrofluoric acid solution from the discharge nozzle 13 toward the grooves 14 formed in the side walls 112a and 112b of the inner tank 11. For this reason, the hydrofluoric acid solution discharged from the discharge nozzle 13 collides with the groove portion 14 and diffuses, and proceeds toward the upper portion of the inner tank 11 as a low-speed and uniform liquid flow. Therefore, the metal components and foreign matters generated in the inner tank 11 float to the upper part of the inner tank 11 without being stirred in the inner tank 11, and are quickly discharged to the outer tank 12 together with the hydrofluoric acid solution.

  Moreover, in the substrate processing apparatus of this embodiment, in order to form a low-speed and uniform hydrofluoric acid solution in the inner tank 11, the hydrofluoric acid solution is efficiently discharged from the inner tank 11, and the inner tank 11 can efficiently supply a new hydrofluoric acid solution. That is, during the etching process, the inside of the inner tank 11 can be efficiently replaced with a new hydrofluoric acid solution, and a clean hydrofluoric acid solution can always act on the substrate W. For this reason, the time for the etching process can be shortened.

  If the diameter of the discharge port 13a of the discharge nozzle 13 is increased, the discharge pressure of the hydrofluoric acid solution is greatly different between the upstream discharge port 13a and the downstream discharge port 13a. However, the substrate processing apparatus 1 of this embodiment does not slow down the flow of the hydrofluoric acid solution by increasing the diameter of the discharge port 13a, but causes the hydrofluoric acid solution to collide with the side walls 112a and 112b of the inner tank 11. This slows down the flow of the hydrofluoric acid solution. For this reason, it is possible to reduce the flow of the hydrofluoric acid solution while preventing the discharge pressure of the hydrofluoric acid solution from greatly differing between the upstream discharge port 13a and the downstream discharge port 13a.

  Moreover, the substrate processing apparatus 1 of this embodiment makes the flow of the hydrofluoric acid solution slow without complicating the configuration of the discharge nozzle 13 itself. For this reason, the replacement efficiency of the hydrofluoric acid solution can be improved while suppressing an increase in the manufacturing cost of the substrate processing apparatus 1 including the discharge nozzle 13.

  Moreover, in this embodiment, the discharge nozzle 13 discharges a hydrofluoric acid solution toward the lower taper surface 14b among the groove parts 14 formed in the side walls 112a and 112b of the inner tank 11. For this reason, the diffused hydrofluoric acid solution can be made to proceed more toward the vicinity of the bottom of the inner tank 11, whereby the replacement efficiency of the hydrofluoric acid solution can be further improved.

<3. Modification>
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, in the above embodiment, the discharge nozzle 13 discharges the hydrofluoric acid solution toward the lower tapered surface 14 b of the groove 14. However, the discharge nozzle 13 discharges the hydrofluoric acid solution toward the other part of the groove 14. May be discharged. As another embodiment, as shown in FIG. 5, the hydrofluoric acid solution may be discharged from the discharge nozzle 13 toward the boundary between the upper and lower tapered surfaces 14a, 14b.

  In the above embodiment, the groove portion 14 is a groove having a V-shaped cross section constituted by a pair of tapered surfaces 14a and 14b. However, the shape of the groove portion 14 is shown in FIGS. 6 and 7, for example. Such a curved surface shape (half-cylinder shape) may be used. That is, it is only necessary that a recess having a shape for rectifying the discharged hydrofluoric acid solution is formed at a position facing the plurality of discharge ports 13 a of the discharge nozzle 13. When the groove portion 14 has a curved surface shape, as shown in FIG. 7, the discharge nozzle 13 is disposed slightly above the central axis of the groove portion 14 so that the hydrofluoric acid solution is discharged toward the upper portion of the groove portion 14. Also good. In this way, the hydrofluoric acid solution discharged from the discharge nozzle 13 can be advanced to the vicinity of the bottom along the curved surface of the groove portion 14, and the flow of the hydrofluoric acid solution from the bottom to the top of the inner tank 11 is good. Can be formed.

  In the above embodiment, the groove 14 is formed at the lower end of the side walls 112a and 112b of the inner tank 11, but the groove 14 may be formed at a position slightly above the side walls 112a and 112b. . Moreover, the groove part 14 may be formed in the bottom wall 111 of the inner tank 11, as shown in FIG.

  Further, the hydrofluoric acid solution may be discharged from the discharge nozzle 13 toward the inner surface of the inner tank 11 without forming the groove portion 14 in the inner tank 11. For example, as shown in FIG. 9, the hydrofluoric acid solution may be discharged from the discharge nozzle 13 toward the side walls 112 a and 112 b of the inner tank 11. Even in such a configuration, the hydrofluoric acid solution can be diffused to reduce the flow velocity, and a low-velocity hydrofluoric acid solution flow can be formed around the substrate W. When the hydrofluoric acid solution is discharged toward the side walls 112a and 112b, it is desirable to discharge the hydrofluoric acid solution perpendicular to the side walls 112a and 112b as shown in FIG. In this way, it is possible to prevent the hydrofluoric acid solution (the hydrofluoric acid solution containing metal components and foreign matters) near the upper portion of the inner tank 11 from being entrained in the discharge liquid flow and transported to the bottom of the inner tank 11.

  In the above embodiment, the hydrofluoric acid solution is used as the processing liquid. However, the substrate processing apparatus of the present invention may process the substrate W using another processing liquid. For example, SC-1 solution, SC-2 solution, CARO acid, pure water or the like may be used as the treatment solution. The present invention can be applied not only to a substrate processing apparatus for processing a semiconductor substrate but also to a substrate processing apparatus for processing various substrates such as a glass substrate for a liquid crystal display device and a glass substrate for a photomask. it can.

It is the longitudinal cross-sectional view which cut | disconnected the substrate processing apparatus by the plane parallel to the main surface of a board | substrate. It is the longitudinal cross-sectional view which cut | disconnected the substrate processing apparatus by the plane perpendicular | vertical to the main surface of a board | substrate. It is the figure which showed the flow of the hydrofluoric acid solution in a processing tank. It is the flowchart which showed the flow of operation | movement of the substrate processing apparatus. It is the figure which showed the shape of the processing tank which concerns on the modification, and the flow of the hydrofluoric acid solution. It is the figure which showed the shape of the processing tank which concerns on the modification, and the flow of the hydrofluoric acid solution. It is the figure which showed the shape of the processing tank which concerns on the modification, and the flow of the hydrofluoric acid solution. It is the figure which showed the shape of the processing tank which concerns on the modification, and the flow of the hydrofluoric acid solution. It is the figure which showed the shape of the processing tank which concerns on the modification, and the flow of the hydrofluoric acid solution. It is the figure which showed the example of the conventional substrate processing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 10 Processing tank 11 Inner tank 12 Outer tank 13 Discharge nozzle 13a Discharge port 14 Groove part 14a, 14b Tapered surface 20 Lifter 30 Hydrofluoric acid solution supply part 40 Hydrofluoric acid solution discharge part 50 Control part 111 Bottom wall 112a-112d Side wall W substrate

Claims (5)

A substrate processing apparatus for processing a substrate by immersing the substrate in a processing solution,
A treatment tank having a side wall and a bottom wall and storing a treatment liquid therein;
Discharging means for discharging a processing liquid into the processing tank;
Discharging means for discharging the processing liquid overflowed from the upper part of the processing tank;
Moving means for moving the substrate up and down between the inside of the processing tank and the upper position of the processing tank;
With
The discharge means has a pair of discharge nozzles,
The pair of discharge nozzles discharge the processing liquid toward the concave portions formed in the pair of side walls opposed to the processing tank, respectively, inside the processing tank,
The substrate processing apparatus , wherein the recess is formed by forming each of the pair of side walls so that a part thereof protrudes outward .   The substrate processing apparatus according to claim 1,
  The substrate processing apparatus, wherein the recess is formed in a lower end portion of the pair of side walls.   The substrate processing apparatus according to claim 1 or 2, wherein
  The substrate processing apparatus, wherein the recess is a groove having a V-shaped cross section that opens toward the inside of the processing tank.   The substrate processing apparatus according to claim 3, wherein
  The substrate processing apparatus, wherein the discharge nozzle discharges a processing liquid toward a lower taper surface among a pair of taper surfaces constituting the groove having a V-shaped cross section.   The substrate processing apparatus according to claim 1 or 2, wherein
  The substrate processing apparatus, wherein the recess is a curved groove opened toward the inside of the processing tank.

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