JP2006093183A - Medical fluid discharging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that, in a conventional medical fluid discharging apparatus, a medical fluid at the front end of a nozzle, which dries and changes in quality, is disposed of at a predetermined time interval, or the medical fluid is recovered from a medical fluid recovery pod connected to the front end of the nozzle, and is circulated to a medical fluid bottle which forces the length of a piping through which to circulate the medical fluid to be lengthy, and the initial input amount of the medical fluid to be increased. <P>SOLUTION: The medical fluid discharging apparatus comprises double nozzle piping, an inner nozzle which is structured to discharge medical fluid as conventionally, and an outer nozzle which is structured to recover and circulate the medical fluid. The medical fluid is circulated by connecting the nozzle to a stand-by port. Moreover, being provided with a filter, the stand-by port can prevent the occurrence of particles. A suck-back nozzle capable of sucking and extruding the medical fluid is provided at the upper part of the nozzle. A regulating valve is connected to each of the inner and outer nozzles, and the operation of the regulating valve and the suck-back valve would rotate the medical fluid only between the nozzle front end and the stand-by port, thus making it possible to shorten the piping length and to reduce the initial input amount of the medical fluid. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a chemical liquid ejecting apparatus that ejects a chemical liquid onto a wafer.

  Among the processes for manufacturing a semiconductor, in a photolithography process, a chemical solution typified by a resist is dropped on a wafer, a film is applied by spin coating, and a pattern is transferred and formed by exposure. Among these, in a chemical solution discharge device that discharges a chemical solution, the chemical solution is discharged from the tip of the nozzle via a pipe from a gallon bottle or a buffer tank. The chemical solution is mainly a liquid in which a polymer is dissolved in an organic solvent.Since the solvent tends to evaporate in the air, the chemical solution at the tip of the nozzle has a viscosity change due to the evaporation of the solvent or a dissolved polymer. It is dried and adheres as particles to the nozzle tip. When the viscosity of the chemical solution changes, the coating film thickness fluctuates, and when particles adhere to the nozzle, the particles may be mixed into the chemical solution during the next wafer coating, leading to defects on the wafer surface.

  Therefore, when waiting while chemicals are not discharged, a method is used in which the nozzle is retracted to a standby pod where the solvent atmosphere is maintained by a pool filled with solvent, and the nozzle tip is prevented from drying by placing the nozzle in the solvent atmosphere. ing. At that time, in order to prevent the chemical at the tip of the nozzle from being completely dried and the viscosity from being changed, a so-called dummy dispensing operation is performed in which the chemical is discharged from the nozzle at regular intervals and discarded. However, when the dummy dispensing is performed, the chemical solution is discarded and cannot be reused, so that the chemical solution is consumed unnecessarily, and the waste solution is increased wastefully.

  As a method for solving such a problem, a technique for collecting and circulating a chemical solution discarded from a nozzle during standby has been proposed.

  Hereinafter, with reference to FIG. 5, a chemical liquid discharge device that is provided in Patent Document 1 and provides a path for discharging and collecting the chemical liquid from the nozzle during standby will be described.

  The nozzle 101, the chemical solution supply pump 103, the chemical solution bottle 104, the coating cup 105, the semiconductor substrate 106, the chemical solution receiver 108, the chemical solution receiver rotational drive system 109, and the chemical solution receiver vertical drive system 110.

  The chemical solution is dropped from the nozzle 101, and after dropping, the chemical solution receiving portion 108 is attached to the nozzle 101 by the rotation drive system 109 and the vertical drive system 110 to form a flow path for the chemical solution. When the chemical solution receiving portion 108 is attached to the nozzle 101, the pump 103 is intermittently operated to constantly circulate the chemical solution without accumulating in the nozzle 101. Thereby, the concentration of the chemical solution is kept constant. When the next dropping is performed, the circulation of the chemical solution is stopped, and the chemical solution receiving unit 108 is separated from the supply nozzle 101 to perform the dropping.

Thus, the chemical solution discarded from the nozzle during standby can be collected and circulated.
JP 59-68489 A

  However, according to the conventional chemical solution discharge apparatus, since it is necessary to extend a pipe that circulates from the chemical solution recovery pod connected to the tip of the nozzle to the chemical solution bottle, there is a problem that the initial chemical solution input amount becomes large.

  The present invention solves the above-mentioned conventional problems, the nozzle is a double tube, the inner nozzle has a function of discharging a conventional chemical solution, the outer nozzle has a function of collecting and circulating the chemical solution, and the nozzle is a standby port. The circulation of the chemical solution was made possible by connecting to. In addition, the standby port includes a filter, which can prevent the generation of particles. A suck-back valve that sucks and pushes out chemicals at the upper part of the nozzle, and an adjustment valve is connected to each of the inner and outer nozzles. Circulate only between.

  By using the present invention, the chemical liquid discharged from the inner nozzle can be sucked to the outer nozzle via the standby port and can be circulated by the suck back valve provided in the upper part of the nozzle during the discharge standby. According to the structure of the present invention, the total piping length of the circulation system can be shortened, and the piping capacity can be reduced.

  By reducing the pipe capacity, it is possible to make the amount of the initially charged chemical solution equal to that when the circulation system is not used.

  Furthermore, a filter is attached to the standby port, and the chemical solution can be kept clean by being filtered as the chemical solution is circulated.

  An elastic cover is attached to the upper part of the standby port, and the solvent atmosphere can be maintained so that the chemical solution present in the filter is not dried.

  A nozzle cover is attached to the outer peripheral portion of the nozzle, and when the nozzle moves to the standby port, the nozzle has an action of spreading the elastic body cover, and an O-ring is provided on the filter housing in the standby port. It is possible to prevent the nozzle from being damaged by applying unnecessary pressure to the nozzle.

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

  FIG. 1 shows a cross-sectional view of the chemical liquid discharge device of the present invention at the time of standby for discharge, FIG. 2 shows a cross-sectional view of the nozzle portion during discharge of the chemical liquid discharge device of the present invention, and FIG. 3 shows the chemical liquid of the present invention Sectional drawing of the standby port part at the time of discharge in a discharge apparatus is shown.

  First, an embodiment of the present invention will be described with reference to FIG. At the time of discharging the chemical solution, the nozzle moves to the upper part of the substrate to be discharged, and is separated from the standby port. FIG. 2 shows the discharge nozzle portion in this state. The discharge nozzle portion includes an inner nozzle 1 that discharges a chemical solution, an outer nozzle 2 that exists on the outer periphery of the inner nozzle 1, and a nozzle cover 13 that serves to protect both nozzles on the outer side. The nozzle has a shape with a narrowed tip.

  The upper part of the inner nozzle is a three-way branch pipe, and the adjustment valve 6 is connected to the branch destination. The outer nozzle is connected to the adjustment valve 5 with the ring-shaped pipe joining one pipe at the upper part. The adjusting valve 5 and the adjusting valve 6 are joined to one pipe and connected to the suck back valve 7. Except for the above nozzle tip, it is installed in the nozzle circulation block. Next, the movement of each part at the time of discharging a chemical | medical solution to a board | substrate is demonstrated. A pump (not shown) is driven from a chemical solution supply unit (not shown) to drop the chemical solution in the discharge system 3. At this time, the regulating valve B6 is closed, and the chemical solution from the supply unit does not sneak into other parts. As shown in FIG. 2, the interface of the chemical solution at the time of discharge is as shown in FIG. 2. The chemical solution of the discharge system 3 has an inner nozzle chemical liquid surface 18 at the tip of the inner nozzle 1, and the chemical solution in the circulation system 4 is the tip of the outer nozzle 2. The outer nozzle chemical liquid surface 19 is adjusted so as to be about 1 cm above the portion. Thereby, it is possible to prevent the chemical liquid in the discharge system 3 and the chemical liquid in the circulation system 4 from mixing with each other, and the chemical liquid in the outer nozzle is prevented from being discharged due to surface tension during discharge.

  Next, FIG. 3 shows a standby port 12 for waiting the nozzle. Inside the waiting port, there is a filter 9 and a housing 17 that is a container surrounding the filter. Above the filter 9, a filter inlet 15 having the same diameter as the cross-sectional shape of the inner nozzle 1 and a same diameter as the cross-sectional shape of the outer nozzle 2 are provided. A donut-shaped filter outlet 16 is provided. FIG. 4 shows a top view and a cross-sectional view of the filter 9. An O-ring 10 is attached to the filter inlet 15 and the filter outlet 16 so as to be in close contact with the nozzle. A nozzle cover stopper O-ring 14 is attached to the upper surface of the housing 17. Furthermore, an elastic cover 11 in a closed state is installed above the standby port 12 so as to cover the entire standby port. Next, the state of the standby port 12 when the nozzle is moving above the substrate will be described with reference to FIG. A chemical solution is accumulated in the filter 9, and the upper interface between the filter inlet 15 and the filter outlet 16 is filled with the chemical solution. There is a solvent atmosphere generating device (not shown) in the standby port 12, and the solvent atmosphere is maintained by the elastic body cover 11 to prevent the chemical solution in the filter from drying.

  The nozzle part and the standby port part at the time of discharge have been described above with reference to FIGS. 2, 3, and 4. Next, the operation during discharge standby will be described with reference to FIG. FIG. 1 shows the positional relationship between the nozzle portion and the standby port portion during discharge standby. First, the operation from the ejection position to the standby position will be described. The nozzle portion shown in FIG. 2 that has finished discharging the chemical liquid moves to the standby port shown in FIG. 3 and slowly descends vertically so as to be accommodated in the standby port. At this time, the nozzle cover 13 spreads the elastic cover 11 covering the upper part of the standby port 12 downward, and eventually the nozzle cover 13 comes into contact with the O-ring 14 attached to the upper part of the housing 17. This serves as a stopper that stops the descent of the nozzle. At this time, the inner nozzle 1 and the outer nozzle 2 are in close contact with the filter inlet 15 and the filter outlet 16 by the O-ring 10. The nozzle cover 13 does not apply excessive pressure to the nozzle tip, and there is no risk of breakage. The next operation is also performed immediately before the operation in which the nozzles are in close contact with each other. When the chemical liquid is discharged in the circulation system 4, the outer nozzle chemical liquid surface 19 is located about 1 cm inside from the tip of the outer nozzle 2. End up. Air smearing must be avoided because it leads to ejection accuracy and pattern defects. For the above reasons, the adjustment valve 5 is opened immediately before the nozzle contact operation, and the suck back valve 7 is pushed out to push down the outer nozzle chemical liquid surface to the nozzle tip. Thereby, air smearing can be prevented.

  When the above operation is completed, the state shown in FIG. 1 is obtained. Next, the operation of the chemical solution circulation according to the present invention will be described. First, in an initial state where the nozzle is in close contact with the standby port 12 (hereinafter referred to as a first state), the regulating valve 6 is closed and the regulating valve 5 is open. From this first state, the operation of closing the regulating valve 5 and the operation of opening the regulating valve 6 are performed, and the pushing-out operation of the suck back valve 7 is performed. Further, the supply side (not shown) of the supply side pipe connected to the discharge system 3 performs an operation of sucking some chemical liquid by a suck back valve or a pump operation. Then, the chemical solution in the pipe from the suck back valve 7 to the inner nozzle 1 flows out to the discharge system 3 in the inner nozzle 1. This state is referred to as a second state. From the second state, the adjusting valve 5 is opened, the adjusting valve 6 is closed, and the suck back valve 7 is sucked. Then, the chemical solution in the discharge system 3 enters the filter 9 through the filter inlet 15 from the tip of the inner nozzle 1. Further, the chemical solution present in the filter is sucked into the circulation system 4 of the outer nozzle 2 through the filter discharge port 16. The chemical solution present in the circulation system 4 passes through the regulating valve 5 and moves into the suck back valve 7. This state is referred to as a third state. By repeating the second state and the third state described above, the chemical liquid circulates in the nozzle and is filtered by the filter, so that the chemical liquid can always be kept clean. Furthermore, since the nozzle tip is sealed, no particles are generated due to the drying of the chemical solution. Furthermore, it is possible to effectively utilize the resist by circulating the resist that has been discarded at regular intervals. In addition, it is no longer necessary to circulate the chemical solution to the chemical supply bottle and tank, and the circulation system piping can be greatly shortened to reduce the initial amount of chemical solution supplied in the discharge device equipped with the chemical solution circulation system. It has become possible to suppress to the same level as the conventional discharge device. As a result, there is an advantage that the old chemical solution does not circulate in the pipe indefinitely, and quality deterioration such as sensitivity fluctuation does not occur.

  The chemical solution discharge device according to the present invention is useful as a technique for effectively utilizing the chemical solution by collecting and circulating the chemical solution that has been discarded in a small amount during standby.

Sectional drawing at the time of discharge waiting in the chemical solution discharge apparatus of the present invention Cross-sectional view of the nozzle part during discharge in the chemical liquid discharge device of the present invention Sectional drawing of the standby port part at the time of discharge in the chemical | medical solution discharge apparatus of this invention The upper surface and sectional view of the filter in the chemical liquid ejection device of the present invention Schematic diagram showing a conventional chemical dispenser

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner nozzle 2 Outer nozzle 3 Discharge system 4 Circulation system 5 Adjustment valve 6 Adjustment valve 7 Suck back valve 9 Filter 10 O-ring 11 Elastic body cover 12 Standby port 13 Nozzle cover 14 Nozzle cover stopper O-ring 15 Filter inlet 16 Filter exhaust Outlet 17 Housing 18 Discharge inner nozzle chemical liquid surface 19 Discharge outer nozzle chemical liquid surface 101 Nozzle 103 Chemical liquid supply pump 104 Chemical liquid bottle 105 Application cup 106 Semiconductor substrate 108 Chemical liquid receiver 109 Rotation drive system 110 Vertical drive system

Claims (13)

An inner nozzle for discharging the chemical,
A double pipe nozzle constituted by an outer nozzle which is a pipe for sucking a chemical solution to the outer periphery of the nozzle;
A chemical solution discharge device comprising a standby port for waiting for the double tube nozzle. A chemical solution discharge device, wherein a filter for passing the chemical solution discharged from the inner nozzle is attached in the standby port. The filter has a structure in which the chemical liquid discharged from the inner nozzle flows from the center portion, and has a donut-shaped discharge portion on the outer peripheral portion of the inflow portion so that the chemical liquid flows out to the outer nozzle. Discharge device. O-rings are attached to the portions where the filter, the inner nozzle and the outer nozzle are in contact with each other.
The chemical nozzle is characterized in that both nozzles are in close contact with the O-ring so as to be inscribed therein. In the upper part of the double pipe nozzle, an adjustment valve A is provided in the pipe of the outer nozzle, another adjustment valve B is provided from the inner nozzle pipe through the branch path, and the pipe 1 is connected through the adjustment valve of each other. A chemical solution discharge device characterized in that the pipe is provided with a suck back valve having a function of sucking and discharging the chemical solution. During discharge standby, after the nozzle is moved to the standby port, the first operation of bringing the nozzle into close contact with the filter in the standby port;
A second operation of operating the suck back valve to discharge the chemical solution from the inner nozzle with the adjustment valve B closed, and to suck the chemical solution from the outer nozzle with the adjustment valve A open; A chemical liquid discharging apparatus, wherein A is closed, the adjustment valve B is opened, and a third operation of pushing the chemical liquid to an inner nozzle by the suck back valve is performed. The chemical liquid ejecting apparatus, wherein the second operation and the third operation are alternately repeated at the time of discharge standby. A chemical solution discharge device comprising a nozzle cover on an outer periphery of the nozzle. The chemical solution discharging apparatus according to claim 1, wherein an elastic body cover having a small hole in the center is provided at an upper portion of the standby port. In the first operation, the nozzle cover pushes the elastic body cover downward, and when shifting to the discharge operation, the nozzle cover moves upward, and the elastic body cover is closed again by an elastic force. And the standby port is hermetically sealed. A housing fixing the filter;
The upper part of the housing is provided with an O-ring, and in the first operation, the nozzle cover is integrally connected to the nozzle cover by being stopped by the housing through the O-ring. A chemical solution discharge device comprising a mechanism for preventing the nozzle being damaged from being excessively pressurized and damaged. The chemical liquid ejecting apparatus is characterized in that the chemical liquid surface of the outer nozzle is adjusted to be positioned above the chemical liquid surface of the inner nozzle during chemical liquid ejection. A chemical liquid ejection apparatus that performs an operation of pushing the outer nozzle chemical liquid surface to a nozzle tip before the nozzle is brought into close contact with an O-ring when shifting to a discharge standby state.

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