JP2016142196A - Pump and application device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pump having excellent durability and capable of discharging liquid with high viscosity, and an application device.SOLUTION: A pump is equipped with: a housing; a flexible member coaxially disposed in the housing and storing liquid; a cylinder portion for storing a working fluid; a plunger which is inserted so as to reciprocate to the cylinder potion, and supplies the working fluid into a gap between the housing and the flexible member and discharges the liquid from the flexible member; and a first seal member and a second seal member which are disposed at an insertion portion of the plunger in the cylinder portion, and slide with the plunder. The first seal member is disposed closer to a tip end side of the plunger than the second seal member, and has a pressure-resistance function. The second seal member has a leakage preventing function.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a pump and a coating apparatus.

  2. Description of the Related Art A chemical solution supply apparatus that applies a chemical solution (liquid) such as a photoresist to a substrate is known (see, for example, Patent Document 1). In this chemical solution supply apparatus, a chemical solution is supplied using a plunger type pump.

JP 2008-128059 A

  However, in the above prior art, it is not assumed that a high-viscosity chemical solution is discharged by a pump, and there is a problem with the durability of the pump. Accordingly, it has been desired to provide a new pump capable of discharging a highly viscous liquid.

  This invention is made | formed in view of such a subject, and it aims at providing the pump and coating device which are excellent in durability and can discharge a highly viscous liquid.

  According to the first aspect of the present invention, a housing, a flexible member that is coaxially disposed in the housing and that stores a liquid, a cylinder portion that stores a working fluid, and the cylinder portion A plunger that is reciprocally inserted to supply the working fluid to a gap between the housing and the flexible member and to discharge the liquid from the flexible member; and A first seal member and a second seal member that are disposed in the insertion portion and are in sliding contact with the plunger, wherein the first seal member is on the distal end side of the plunger with respect to the second seal member. The second sealing member is a sealing member having a pressure resistance function and the second sealing member is a sealing member having a leakage prevention function.

According to the pump according to the first aspect, since the first seal member having a pressure-resistant function is provided on the plunger tip side, the high-viscosity liquid can be discharged well and has excellent durability. Become. On the other hand, although the first sealing member is excellent in pressure resistance, the sealing performance is relatively low. Therefore, there is a possibility that the working medium leaks from the gap between the first seal members, but even in this case, since the second seal member having a leakage preventing function is provided, the operation leaked from the gap between the first seal members. It is possible to prevent a problem that the medium leaks to the outside of the cylinder portion.
For example, if the second seal member is arranged on the plunger tip side, the second seal member that vibrates with the reciprocating motion of the plunger may cause the working medium to pulsate. Then, the pulsation of the working medium is transmitted to the liquid, so that the quality of the liquid coating film may be deteriorated. In the present invention, since the first seal member is disposed on the plunger tip side, the working medium is prevented from pulsating.
Therefore, a pump having excellent durability and capable of discharging a highly viscous liquid is provided.

The first aspect may include a detection unit that detects an amount of the working fluid that has leaked to the second seal member side from a gap between the first seal member and the plunger.
According to this configuration, it is possible to easily determine whether or not maintenance is necessary by using the detection result of the leakage amount of the working medium.

The first aspect may be configured to include a determination unit that determines a state related to the pump body based on a detection result of the detection unit.
According to this configuration, it is possible to reliably determine whether the pump body needs maintenance. Therefore, when the maintenance of the pump is appropriately performed, it is possible to prevent the occurrence of a malfunction such as a failure of the pump due to poor maintenance.

  According to a second aspect of the present invention, in the coating apparatus comprising: an application unit that applies a liquid to an object to be applied; and a liquid supply unit that supplies the liquid to the application unit. A coating apparatus using the pump of the first aspect is provided.

  According to the coating apparatus which concerns on a 2nd aspect, since the pump which concerns on a 1st aspect is provided, the reliable coating apparatus which can apply | coat a highly viscous liquid to a to-be-coated object over a long term can be provided.

  According to the present invention, it is excellent in durability and can discharge a highly viscous liquid.

The figure which shows schematic structure of the coating device which concerns on 1st Embodiment. The schematic block diagram of the pump which concerns on 1st Embodiment. Sectional drawing which shows the principal part structure of the pump which concerns on 1st Embodiment. Sectional drawing which shows the principal part structure of the pump which concerns on 2nd Embodiment.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the present embodiment, a coating apparatus provided with a pump as a liquid supply means will be described as an example. The coating apparatus of this embodiment is for coating a chemical liquid (liquid) such as a photoresist having a relatively high viscosity on a semiconductor substrate (wafer).
In addition, in the drawings used in the following description, in order to make the features easy to understand, there are cases where the portions that become the features are enlarged for the sake of convenience, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent.

(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of a coating apparatus according to the present embodiment.
As shown in FIG. 1, a coating apparatus 100 includes a pump 20 as a liquid supply means, a liquid supply path 11, a valve 12 that can close (open and close) the liquid supply path 11, and a semiconductor substrate as an object to be coated. 1 includes an application unit 13 for applying a liquid to 1 and a stage 14 for holding the semiconductor substrate 1.

  The liquid supply path 11 connects between the pump 20 and the application unit 13 and supplies liquid from the pump 20 side to the application unit 13. The valve 12 is provided in the middle of the liquid supply path 11. The liquid supply path 11 includes an upstream supply path 11 a that connects the valve 12 and the pump 20, and a downstream supply path 11 b that connects the valve 12 and the application unit 13. Examples of the application unit 13 include an inkjet head and a slit nozzle. The valve 12 may not be provided in the middle of the liquid supply path 11.

FIG. 2 is a schematic configuration diagram of the pump 20. FIG. 3 is a cross-sectional view illustrating a schematic configuration of a main part of the pump 20.
As shown in FIG. 2, the pump 20 is a plunger type pump having a main body portion 21 and a cylinder portion 22. The main body portion 21 includes a case member (housing) 23 fixed to the cylinder portion 22 by bolts (not shown), and a flexible tube (flexible member) 24 attached in the case member 23. .

  The case member 23 includes a connection portion 26 connected to the liquid supply path 11 (upstream supply path 11a). A fluid discharge port 26 a that communicates with the flexible tube 24 is formed in the connection portion 26. The fluid discharge port 26 a supplies the liquid discharged from the flexible tube 24 by the working medium 35 to the application unit 13 side through the liquid supply path 11.

  The flexible tube 24 is composed of an elastic member that can expand and contract in the radial direction. The flexible tube 24 is accommodated in the case member 23 so as to form a gap with the case member 23. This gap constitutes the main body side drive chamber 25 that causes the flexible tube 24 to expand and contract when the working medium 35 flows in. The flexible tube 24 contains a chemical solution such as a resist solution therein. The flexible tube 24 may have a configuration in which a chemical liquid is stored therein by being supplied from a chemical liquid tank (not shown) as needed.

  The flexible tube 24 is made of, for example, a tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA) that is a fluororesin. Similarly, the connecting portion 26 is formed of PFA. These members formed by PFA do not react with the photoresist solution. However, depending on the type of the chemical solution, the material is not limited to PFA, and any other flexible material such as a resin material or a rubber material may be used as the material of the flexible tube 24 as long as it is an elastically deformable material. Similarly, the connecting portion 26 may use other resin material or metal material as a material.

  The cylinder portion 22 includes a cylinder body 30 and a piston (plunger) 31 assembled in a reciprocating manner in the axial direction with respect to a cylinder hole (plunger insertion portion) 30 a formed in the cylinder body 30. The cylinder part 22 has a drive device 32 for reciprocating the piston 31.

  In the cylinder portion 22, a piston-side drive chamber 33 is formed between the front end surface of the piston 31 and the bottom surface 30b of the cylinder hole 30a. In the cylinder portion 22, the cylinder side drive chamber 33 communicates with the main body side drive chamber 25 on the main body portion 21 side through a communication hole 34 formed in the cylinder body 30.

  A drive working medium 35 is enclosed in the main body side drive chamber 25 and the cylinder side drive chamber 33. The working medium 35 is composed of, for example, an incompressible medium. The working medium 35 in the drive chambers 25 and 33 communicates with each other through the communication hole 34.

  In the present embodiment, the cylinder portion 22 includes a front seal member (first seal member) 40 and a rear seal member (second seal member) 41 between the cylinder body 30 and the piston 31. ing.

  The front seal member 40 and the rear seal member 41 are incorporated between the cylinder body 30 and the piston 31. Specifically, the front seal member 40 and the rear seal member 41 are in sliding contact with the outer peripheral surface of the piston 31 by being incorporated in the inner peripheral surface of the cylinder hole 30a.

  The front seal member 40 is a ring-shaped seal member that is disposed closer to the distal end side of the piston 31 than the rear seal member 41 and has a pressure resistance function. The rear seal member 41 is composed of a ring-shaped seal member having a leakage prevention function.

  The rear seal member 41 is made of a material having a low hardness such as rubber, and has a pressure resistance of about 0.5 to 1.0 MPa, for example. On the other hand, the front seal member 40 is made of a resin material that is sufficiently higher than the rear seal member 41, for example, having a pressure resistance of about 20 MPa.

  Based on such a configuration, the pump 20 contracts the cylinder-side drive chamber 33 when the piston 31 is moved forward toward the bottom surface 30b of the cylinder hole 30a. At this time, the working medium 35 in the cylinder side drive chamber 33 flows into the main body side drive chamber 25. The flexible tube 24 is pressed by the working medium 35 and contracts. Thereby, the liquid accommodated in the flexible tube 24 is discharged | emitted from the fluid discharge port 26a to the liquid supply path 11 (upstream supply path 11a).

  On the other hand, when the piston 31 is moved in the backward direction, the cylinder-side drive chamber 33 expands, so that the working medium 35 in the main body-side drive chamber 25 flows into the cylinder-side drive chamber 33, and the working medium 35 allows The pressing of the flexible tube 24 is released.

  Based on such a configuration, when the piston 31 in the cylinder hole 30a reciprocates, the pump 20 expands and contracts the main body side drive chamber 25 due to the movement of the working medium 35 enclosed in the drive chambers 25 and 33, The chemical liquid can be supplied to the application unit 13 through the liquid supply path 11 by opening and closing the valve 12 in conjunction with the expansion and contraction of the main body side drive chamber 25.

  By the way, pressure is applied to the front seal member 40 disposed on the front end side of the piston 31 from the working medium 35 that has become a high pressure in the cylinder side drive chamber 33. In the present embodiment, since the front side seal member 40 has a pressure resistance function, the deterioration rate of the sealing performance due to wear or deterioration of the front side seal member 40 can be suppressed.

  In general, the front seal member 40 having a pressure resistance function has a low followability with respect to the surface shape of the piston at the time of sliding contact with the piston 31, so that the seal function is relatively low. Therefore, a part of the working medium 35 leaks in the outer direction of the cylinder hole 30a through the gap between the front seal member 40 and the cylinder hole 30a.

  On the other hand, since the pump 20 of the present embodiment includes the rear seal member 41 having a leakage prevention function in the direction in which the working medium 35 leaks, the pump 20 travels through the gap between the front seal member 40 and the cylinder hole 30a. The working medium 35 leaking out of the cylinder hole 30a is sealed by the rear seal member 41 and is prevented from leaking out of the cylinder hole 30a.

  Here, when the arrangement positions of the front seal member 40 and the rear seal member 41 are exchanged, that is, a seal member having a leakage prevention function is arranged on the distal end side of the piston 31, and the seal member having a pressure resistance function is arranged on the piston 31. When arranged on the side opposite to the tip, the seal member having a leakage preventing function vibrates because the pressure resistance is low during the reciprocating operation of the piston 31. Then, the vibration generated in the seal member having a leakage prevention function may be transmitted to the working medium 35 to cause the working medium 35 to pulsate.

  When the pulsating working medium 35 is supplied to the main body side drive chamber 25, the pulsation is also transmitted to the chemical solution in the flexible tube 24 pressed by the working medium 35, so that the coating unit 13 is placed on the semiconductor substrate 1. The surface of the coating film of the chemical applied to the surface of the film undulates, greatly reducing the quality of the coating film.

  In order to eliminate the occurrence of such a problem, in the pump 20 of the present embodiment, the seal member having a pressure-resistant function is arranged on the piston tip side as described above, and the leakage for sealing the leaked working medium 35 is sealed. Since the structure in which the seal member having the prevention function is arranged on the plunger base side is employed, it is possible to prevent the working medium 35 from pulsating as described above. Therefore, the quality of the coating film of the chemical solution caused by the pulsation of the working medium 35 does not deteriorate.

As described above, according to the pump 20 according to the present embodiment, since the front seal member 40 having a pressure resistance function is provided on the piston tip side, a high-viscosity chemical solution can be discharged well, and over a long period of time. Excellent sealing performance can be exhibited.
Further, in the present embodiment, by combining the front seal member 40 and the rear seal member 41, the working fluid 35 leaks out of the cylinder by the rear seal member 41 while exerting a pressure resistance function by the front seal member 40. Can be prevented.
Furthermore, the pulsation which arises in the working medium 35 can be suppressed by arrange | positioning the front side sealing member 40 and the rear side sealing member 41 in this order from the piston front end side.

  Therefore, according to the coating apparatus 100 of the present embodiment, since the pump 20 having excellent durability and capable of discharging a highly viscous liquid is provided, the highly viscous chemical liquid is applied to the semiconductor substrate 1 over a long period of time. A highly reliable device that can be provided is provided.

(Second Embodiment)
Next, the configuration of the pump according to the second embodiment will be described. FIG. 4 is a cross-sectional view illustrating a schematic configuration of a main part of the pump according to the present embodiment. In addition, the same code | symbol is attached | subjected about the structure and member which are common in 1st Embodiment, and the description shall be abbreviate | omitted or simplified.

  As shown in FIG. 4, the pump 50 according to this embodiment includes a detection unit 51 that can detect the working medium 35 and a control unit 52 that controls driving of each component of the pump 50. The detection unit 51 is for detecting the amount of the working medium 35 leaked between the front seal member 40 and the rear seal member 41. Based on the detection result of the detection unit 51, the control unit 52 is, for example, for determining whether maintenance regarding the pump is necessary as information regarding the pump body.

  In the present embodiment, the detection unit 51 is disposed in a recess 43 formed on the inner wall surface of the seal holding unit 42 that holds the front seal member 40 and the rear seal member 41 so as to be in sliding contact with the outer peripheral surface of the piston 31. Has been. The recess 43 functions as a buffer that accommodates the working medium 35 leaking between the front seal member 40 and the rear seal member 41.

  The inner wall surface of the seal holding part 42 constitutes a part of the cylinder hole 30a. The recess 43 is formed along the circumferential direction of the inner wall surface of the seal holding member 42. The recess 43 may be formed over the entire circumferential direction of the inner wall surface of the seal holding member 42.

  Also in the pump 50 of the present embodiment, the cylinder part 22 is sealed by sealing the working medium 35 leaked in the outer direction of the cylinder hole 30a through the gap between the front seal member 40 and the cylinder hole 30a by the rear seal member 41. To prevent leakage to the outside.

  By the way, when the working medium 35 leaking into the gap between the front seal member 40 and the cylinder hole 30a exceeds a predetermined amount, the sealing performance of the rear seal member 41 is exceeded, and the working medium 35 reaches the outside of the cylinder portion 22. In the worst case due to leakage, the pump 50 may be damaged. Therefore, in order to prevent a failure of the pump 50, it is desirable to perform maintenance work on the pump 50 at a timing when a predetermined amount of the working medium 35 leaks out.

  On the other hand, in the pump 50 of the present embodiment, the control unit 52 can determine the amount of leakage of the working medium 35 in the gap between the front seal member 40 and the cylinder hole 30a based on the detection result from the detection unit 51. ing. Therefore, the controller 52 can easily and reliably determine whether or not the pump 50 needs maintenance when the amount of leakage of the working medium 35 reaches a predetermined value. For example, when it is determined that the maintenance of the pump 50 is necessary, the control unit 52 may notify an alarm (not shown) or display that the maintenance is necessary on a display unit (not shown). According to this, the operator can easily recognize the maintenance time of the pump 50, and the maintenance is appropriately performed, thereby preventing the occurrence of a malfunction such as failure of the pump 50 due to maintenance failure. be able to.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification. For example, in the above embodiment, the case where the pump of the present invention is applied as the supply means for supplying the photoresist (liquid) to the application unit 13 is described as an example. However, the type of liquid to be supplied is not limited to the photoresist. Any liquid can be used as long as it has a relatively high viscosity and needs to be pumped. That is, the pump of the present invention can be applied to any liquid supply means that pumps a highly viscous liquid material regardless of the type of liquid.

DESCRIPTION OF SYMBOLS 1 ... Semiconductor substrate (to-be-coated object) 20, 50 ... Pump (liquid supply means), 22 ... Cylinder part, 23 ... Case member (housing), 24 ... Flexible tube (flexible member), 30a ... Cylinder hole (plunger insertion part), 31 ... piston (plunger), 40 ... front seal member (first seal member), 41 ... rear seal member (second seal member), 51 ... detection part, 52... Control unit (determination unit), 100.

Claims (4)

A housing,
A flexible member disposed coaxially in the housing and containing a liquid;
A cylinder portion for storing the working fluid;
A plunger that is reciprocally inserted into the cylinder portion, supplies the working fluid to a gap between the housing and the flexible member, and discharges the liquid from the flexible member;
A first seal member and a second seal member, which are disposed in an insertion portion of the plunger in the cylinder portion and slidably contact the plunger;
The first seal member is a seal member that is disposed closer to the distal end side of the plunger than the second seal member and has a pressure resistance function,
The second seal member is a seal member having a leakage prevention function. The pump according to claim 1, further comprising: a detection unit that detects an amount of the working fluid that has leaked toward the second seal member from a gap between the first seal member and the plunger. The pump according to claim 2, further comprising a determination unit that determines a state related to the pump body based on a detection result of the detection unit. In an application apparatus comprising: an application unit that applies liquid to an object to be applied; and a liquid supply unit that supplies the liquid to the application unit.
The applicator using the pump as described in any one of Claims 1-3 as said liquid supply means.

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