JP2665211B2 - Liquid jet nozzle for coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating liquid jet nozzle for dropping a coating liquid onto a wafer as a semiconductor substrate and applying the liquid to the wafer.

[0002]

2. Description of the Related Art A coating liquid jet nozzle forms a thin film on the surface of a semiconductor wafer by applying a chemical solution during the manufacturing process of the semiconductor wafer. At that time, the thickness of the thin film formed by the formed chemical becomes an important factor relating to the characteristics of the wafer.

FIGS. 4 (a) and 4 (b) are views showing examples of a conventional nozzle for ejecting a coating liquid. Conventionally, this type of application liquid ejection nozzle has a shape in which the tip of a tubular nozzle body 11 is narrowed down as shown in FIG. 4A, for example. Then, the chemical liquid 12, which is the application liquid, sucks back due to the suction operation of the liquid sending pump, and the chemical liquid 12, which stops, is drawn in from the discharge port of the nozzle body 11, so that the chemical liquid 12 is prevented from coming into contact with the outside air even if a little. 12 was prevented from being solidified by drying.

However, in this case, although the discharge port is small, the chemical liquid 12 is always in contact with the atmosphere. Therefore, when the chemical liquid 12 is not used for a long time, solidification of the chemical liquid 12 cannot be avoided, and the nozzle main body cannot be solidified. Even if clogging or clogging does not occur in the inside of the nozzle 11, the viscosity of the chemical solution 12 increases, and the chemical solution 12 dropped from the discharge port of the nozzle body 11 does not scatter due to rotational force, which causes a coating film defect.

A technique for solving this problem is disclosed, for example, in Japanese Utility Model Laid-Open No. 4-56327. This nozzle is provided with a valve mechanism for opening and closing the opening at the tip of the nozzle. In one embodiment, a valve body for opening and closing an opening is provided in the nozzle body, and the valve body is pneumatically operated to open and close the valve body.

[0006] As another example of the present application, FIG.
As shown in FIG. 1, a valve seat 16 for inserting the tip of the nozzle body 1 and closing the opening is provided with a container-shaped on-off valve 13 having a bottom portion. The container-shaped on-off valve 13 is designed to supply the cleaning liquid into the container from the cleaning liquid supply port 14 so that the nozzle body 11 is immersed in the cleaning liquid and does not come into contact with the outside air. Further, a cleaning liquid drain port 15 for discharging dirty cleaning liquid is provided, and the nozzle body 11 and the on-off valve 13 are usually located at separate positions, and when the nozzle is not used, as shown by the arrow, the on-off valve 13, the nozzle body 11 is inserted into the opening of the on-off valve 13 so that the discharge port of the nozzle body 11 does not come into contact with the outside air, thereby preventing the chemical solution from solidifying.

[0007]

However, in the former valve mechanism, since the member called the bellows is housed in the nozzle body, the nozzle itself becomes large, overhangs and burdens the joint, and the watertightness of the packing of the joint is reduced. There is a problem that the liquid crystal cannot be maintained, and often the chemical leaks from the joint to contaminate the wafer. In addition, the chemical liquid enters into the recess of the bellows built in the nozzle body, and the movement of the bellows is braked, so that it is difficult for the valve body to operate smoothly. In addition, although the chemical does not directly contact the outside air, during a long period of non-operation, the slightly leaked outside air or a change in temperature causes the chemical to enter the dent and the bellows does not operate. Further, there is a drawback that air supply and sequence control for operating the bellows are required, the apparatus becomes complicated, the probability of failure increases, and it is difficult to apply the method to actual production.

On the other hand, in the case of an on-off valve filled with a cleaning liquid,
Although it does not place a burden on the nozzle tip because it is placed separately, it requires a movement positioning mechanism for aligning the nozzle body with the on-off valve and a mechanism for inserting and removing the nozzle,
In addition, it is necessary to provide a sequence control and an interlock for operating these mechanisms, which not only increases the cost but also complicates the apparatus, increases the probability of inducing a failure, and lowers the operation rate.

Accordingly, an object of the present invention is to provide an inexpensive coating liquid jetting nozzle capable of preventing the drying of a chemical solution and the solidification due to moisture absorption, and smoothly dropping the chemical solution without applying an unnecessary load to the nozzle tip. That is.

[0010]

SUMMARY OF THE INVENTION The present invention is characterized in that the coating liquid stays and flows outward from the outer wall or the inner wall of the nozzle body having an opening through which the coating liquid flows out by the pumping pressure. A plurality of plate-like piece members extending, the plate-like piece member elastically deforms outward by the sending pressure of the application liquid supplied from the opening, opens the discharge port, and sends the coating liquid of the coating liquid. And the plate-like piece member springs back and returns to the inside to close the discharge port.

It is preferable that a film member is provided on the inside surrounded by the plate-like piece member and hardly adheres to the coating liquid. Further, the plate-like piece member is integrated with the nozzle body or is joined to the nozzle body. In another, the plate-like piece member is provided with a spring member that is attached to the nozzle body via a hinge and that applies an elastic force to the plate-like piece.

[0012]

Next, the present invention will be described with reference to the drawings.

FIGS. 1A to 1C are a sectional view (a) and a view (b), (c) showing the order of operation of a coating liquid ejection nozzle according to a first embodiment of the present invention. As shown in FIG. 1, the coating liquid ejection nozzle has an opening 4 for stopping the liquid medicine 12 and ejecting the liquid medicine 12 by the pumping pressure of the pump.
And a plurality of plate-like pieces 5 extending outward from the periphery of the nozzle body 1 having the shape. The plate-like piece 5 is elastically deformed outward by the sending pressure of the chemical solution 12 to open the discharge port 3 and to discharge the coating liquid. There is provided a valve mechanism 2 that loses the feed pressure and causes the plate-like piece 5 to spring back and return inside to close the discharge port 3.

The operation of the application liquid jet nozzle is as follows. First, while the chemical liquid 12 remains in the nozzle main body 1, the plate-like pieces 5 of the valve mechanism 2 are alternately arranged as shown in FIG. The bud discharge port 3 is closed. Next, when the diaphragm type liquid supply pump of the apparatus is operated, the chemical solution 12 through the opening 4 of the nozzle body 1 is sent to the valve mechanism 2 at a predetermined liquid supply pressure,
The plate-shaped piece 5 is pushed outward by the liquid sending pressure. Then, as shown in FIG. 1 (b), the ejection port 3 is formed by opening the plate-like piece 5, and the chemical droplet 12a is dropped. Next, when one operation of the liquid sending pump is completed, the chemical solution 12 is sucked back into the nozzle body 1 and, as shown in FIG.
Is stopped in the nozzle body 1, the plate-like pieces 5 of the valve mechanism 2 spring back, and their tips close each other to close the discharge port 3 and shut off the chemical solution 12 stopped from the outside air.

When manufacturing the coating liquid jet nozzle, the nozzle body 1 is manufactured by, for example, bending a stainless steel pipe with a bender. And the valve mechanism 2
Separately, a stainless steel plate is formed into a bullet-shaped member by press drawing and heat-treated to provide spring properties. Thereafter, a slit is formed in the bullet-shaped member by electric discharge machining, for example, in a range of about 0.02 to 0.05 mm. Then, the nozzle body and the bullet-shaped member are welded by an electron beam or a laser beam. Next, the inner surface of the nozzle member integrated by welding is subjected to teplon coating.

Before the heat treatment of the bullet-shaped member, slit processing is performed by electric discharge machining, and the plate-shaped pieces 5 are formed so that the side portions of the respective plate-shaped pieces 5 overlap with each other so that no gap is formed in the slit. Is desirable. If the plate-like piece 5 is formed and heat-treated in this way, the hermetic valve mechanism 2 can be obtained as well as maintaining the watertightness of the chemical solution.

FIGS. 2 (a) to 2 (c) are a sectional view (a) and a view (b), (c) showing the order of operation of a coating liquid ejection nozzle according to a second embodiment of the present invention. This application liquid ejection nozzle is applied to a relatively large nozzle. As shown in FIG. 2, the application liquid ejection nozzle is attached to the outer periphery of the nozzle body 1 via a hinge 9 and a leaf spring 8, and each is outward. This is to provide a valve mechanism 2a including a plurality of extending plate-like pieces 5a and a Teflon tube 7 attached to the inner surface of the space surrounded by the plate-like pieces 5a.

The leaf spring 8 is attached to a hinge 9, and a repulsive force acts in a direction in which the hinge 9 opens, and acts to crush the plate-like piece 5a. The Teflon tube 7 is a stretchable bag-shaped member that covers the inner wall of the nozzle body 1 and the inner wall of the valve mechanism 2a, and when the discharge port 3 is closed, each plate-like piece 5
The gap of a is closed. Further, as is well known, the Teflon tube 7 does not have adhesiveness to the chemical solution 12 and has a very small coefficient of friction so that the chemical solution 12 flows smoothly. Further, a hole is provided at the tip of the Teflon tube 7, and the size of the hole is set such that the hole is sufficiently widened by a liquid supply pressure of the chemical solution 12 so that a predetermined amount of the chemical solution 12 passes.

The operation of the application liquid jet nozzle is shown in FIG.
As shown in (a) and (b), the plate-shaped piece a is recessed by the hinge 9 by the repulsive force of the leaf spring 8 and the discharge port 3 is closed.
Next, as shown in FIG. 2 (c), the stopped chemical solution 12 is pushed out by one operation of the pump.
The upper piece 5a is pushed outward by the liquid sending force, the hole of the Teflon tube 7 is widened to form the discharge port 3, and the chemical droplet 12a is dropped from the projecting port 3. When one operation of the pump is completed, as shown in FIGS. 2A and 2B, the chemical solution 12 is sucked back and stays in the nozzle body 1, and the plate-shaped piece a is restored by the restoring force of the leaf spring 8. Close the depression discharge port 3.

FIGS. 3 (a) to 3 (c) are cross-sectional views of a coating liquid ejection nozzle showing a third embodiment of the present invention.
(B) and an enlarged view (c). As shown in FIG. 3, the application liquid ejection nozzle includes a valve mechanism 2 b formed of a plurality of elastic plate-like pieces 5 b extending from the periphery of the inner wall of the opening 4 of the nozzle body 1 to cover the opening 4. That is.

As shown in FIG. 3 (c), the plate-like piece 5b is formed in a fan shape, and adjacent sides are provided with overlapping portions. As shown in FIG. 3 (b), the chemical liquid 12 is pushed out of the opening 4 by one operation of the pump, and the plate-like piece 5b is moved outward by the pressure of the chemical liquid 12, as shown in FIG. The discharge port 3 is deformed. Then, the extruded chemical solution 12 is dropped as a chemical solution 12a. Next, the chemical solution 12 is sucked back by stopping the operation of the pump, and the plate-like piece 5b springs back to close the discharge port 3 as shown in FIG. This can be prevented.

In manufacturing the liquid jet nozzle for application, the nozzle body 1 is manufactured by bending a stainless steel pipe with a bender. The plate-like piece 5b of the valve mechanism 2 heats a stainless steel plate so as to have a spring property, and punches it in a fan shape with a press die to produce a blank. Thereafter, the plate-shaped pieces 5b are arranged on the end face of the opening 4 of the nozzle body 1 and fixed by a jig, and then the plate-shaped piece 5b and the end face are welded and fixed by an electron beam welding method. Then, the inside of the nozzle body 1 and the plate-like piece 5b are coated with Teflon so that the chemical solution does not adhere.

[0023]

As described above, according to the present invention, the spring is formed by opening from the periphery of the opening of the nozzle body where the chemical liquid stays and opening outward by the liquid supply force of the chemical liquid, exposing the opening and eliminating the liquid supply force. By providing a valve mechanism composed of a plurality of elastic member pieces that back and close the opening, the nozzle itself has the function of an on-off valve without providing a particularly complicated on-off valve in the nozzle body, and the chemical solution contacts the outside air. Therefore, the solidification of the chemical solution retained in the nozzle body was prevented, and the chemical solution was constantly dripped smoothly.
As a result, there is an effect that the operation rate is improved and the obtained coating film can be obtained uniformly and stably.

In addition, there is no need for a special on-off valve or a sequence control and mechanism for operating as in the prior art, so that there is an effect that it can be obtained at extremely low cost. Further, since the opening and closing of the opening can be performed by a simple mechanism depending on the presence or absence of the liquid feeding force of the chemical solution, there is also obtained an effect that an unnecessary complicated mechanism does not have a failure and the operation rate of the apparatus can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a coating liquid ejection nozzle according to a first embodiment of the present invention, and FIG.
(C).

FIG. 2 is a sectional view (a) and a view (b) showing an operation order of a coating liquid ejection nozzle according to a second embodiment of the present invention;
(C).

FIGS. 3A and 3B are a sectional view (a), (b) and an enlarged view (c) of a coating liquid ejection nozzle according to a third embodiment of the present invention.

FIG. 4 is a view showing an example of a conventional nozzle for ejecting a liquid for application.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 11 Nozzle main body 2, 2a, 2b Valve mechanism 3 Discharge port 4 Opening 5, 5a, 5b Plate-like piece 7 Teflon tube 8 Leaf spring 9 Hinge 10 Overlapping part 12 Chemical liquid 12a Chemical droplet 13 Open / close valve 14 Cleaning liquid supply port 15 Cleaning liquid Drainage port 16 Valve seat

Claims (5)

(57) [Claims] A plurality of plate-like members extending outward from a periphery of an outer wall or an inner wall of a nozzle main body having an opening through which a coating liquid stays and the coating liquid flows out by a pumping pressure. The plate-like member elastically deforms outward by the pressure of the application liquid supplied from the opening to open the discharge port, and the pressure of the application liquid is lost, and the plate-like member springs back. A coating liquid ejection nozzle comprising a valve mechanism that returns inside and closes the discharge port. 2. The coating liquid jet nozzle according to claim 1, further comprising a film member interposed inside the plate-shaped member and hardly adhered to the coating liquid. 3. The liquid jet nozzle for application according to claim 1, wherein the plate-shaped piece member is integrated with the nozzle body. 4. The coating liquid ejection nozzle according to claim 1, wherein the plate-shaped piece member is joined to the nozzle body. 5. The coating according to claim 1, wherein said plate-shaped piece member is provided with a spring member attached to said nozzle body via a hinge and applying an elastic force to said plate-shaped piece. Liquid jet nozzle.