KR20070107226A - Apparatus and method for dispensing photosensitive solution in semiconductor device fabrication equipment - Google Patents

Abstract

A photoresist supplying apparatus and a method in a semiconductor device fabricating equipment are provided to reduce bubbles generated in an integrated trapping tank and consumption of the photoresist. First and second supplying containers(3,4) have an internal storage for storing a photoresist therein. An integrated trapping tank(50) traps the photoresist supplied from any one of the supplying units. A pump unit(20) pumps the photoresist stored in the integrated trapping tank to a pumping output terminal(L8). A filter part(30) filters the photoresist pumped by the pump unit. A monitoring unit is installed in pipe lines(L1,L2) between the integrated trapping tank and the supplying containers to monitor an empty state of the photoresist.

Description

Apparatus and method for dispensing photosensitive solution in semiconductor device fabrication equipment

1 is a view of a photosensitive liquid supply apparatus according to the prior art

2 is a view showing a photosensitive liquid supply apparatus according to an embodiment of the present invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus for manufacturing a semiconductor device, and more particularly, to a photoresist supply device for supplying a photoresist such as a photoresist to a semiconductor wafer, and a supply method thereof.

In recent years, with the rapid spread of information media such as portable multimedia players (PMPs), computers, and the like, the functions of semiconductor devices such as semiconductor memories and the like have been rapidly developed. In the case of recent semiconductor products, high integration of products is essential for low cost and high quality to secure competitiveness. In order to achieve high integration, scale-down including the operation of thinning and shortening gate oxide film thickness and channel length of a transistor device is accompanied, and accordingly, semiconductor manufacturing processes and manufacturing equipments are being developed in various forms. In particular, as users demand high-performance devices, the function and operation performance of manufacturing equipment for manufacturing such semiconductor devices are very important.

In general, a manufacturing apparatus for processing a wafer in a semiconductor manufacturing process includes a transfer robot for transferring a wafer, a coater for applying a photoresist on the wafer, a baking unit for baking the applied photoresist, and the wafer. An alignment unit for aligning the photosensitive film at a predetermined position, an exposure unit for providing an exposure source so that the pattern of the mask or reticle is transferred to the photoresist film on the wafer, and the exposed photoresist film is developed to obtain a photoresist pattern to be used as an etching mask. And a developing device for etching the exposed film using the photosensitive film pattern as an etching mask.

The photoresist supply device for supplying the photoresist in the coater equipment included in the manufacturing equipment typically has a configuration as shown in FIG. 1. That is, the photosensitive liquid supply device traps the supply vessels 3 and 4 having an internal space for accommodating the photosensitive liquid such as photoresist by a predetermined capacity and the photosensitive liquids supplied from the supply vessels 3 and 4 First and second trap tanks 10 and 11 to supply the photosensitive liquid uniformly without bubbles, and a pump unit 20 for pumping the photosensitive liquid stored in the first and second trap tanks 10 and 11; , Spraying the filter unit 30 for removing bubbles contained in the photosensitive liquid pumped from the pump unit 20 and the surface of the wafer 100 which rotates the filtered photosensitive liquid from the filter unit 30. It may include a nozzle 90 for. Pipe lines L1 and L2 are respectively installed between the supply vessels 3 and 4 and the first and second trap tanks 10 and 11 so as to transfer photoresist. Pipe lines L20 and L21 connected to the first and second trap tanks 10 and 11 respectively discharge the photosensitive liquid and the air bubbles respectively accommodated in the first and second trap tanks 10 and 11 to the outside. Drain lines are performed. In addition, the pipelines L5 and L6 respectively connected to the tank open valves 12 and 13 may receive the photosensitive liquids respectively received in the first and second trap tanks 10 and 11 into the inlet line of the pump unit 20. L7). The pipeline L9 provided with the bubble detection sensor 22 is a photosensitive liquid delivery line connected between the pump unit 20 and the filter unit 30, and the pipeline L10 is filtered by the filter unit 30. It is a line which performs the function which transfers a photosensitive liquid to the nozzle 90. FIG.

Meanwhile, the sensors 14 and 15 installed in the first and second trap tanks 10 and 11 respectively detect bubble generated in each tank when the containers 3 and 4 are replaced. As a sensor, one sensor is provided with a light emitting part and a light receiving part.

In FIG. 1, a photoresist flowing process in which a photoresist such as a photoresist in at least one of the supply vessels 3 and 4 is supplied to the upper portion of the wafer 100 through the injection nozzle 90 is as follows. . Assuming that the photosensitive liquid 5 contained in the supply vessel 4 of the supply vessels 3 and 4 is applied onto the wafer 100, the tank open valve 13 of the tank open valves 12 and 13 is In the closed state, the tank open valve 12 is in the open state. Here, the opening and closing operations of the tank open valves 12 and 13 may be electrically controlled by the controller when the controller of the photosensitive liquid supply device (not shown) senses an emptyness of the photosensitive liquid. When the pump in the pump unit 20 performs the pumping operation, the photoresist that is temporarily stored in the first trap tank 10 through the pipeline L1 connected to the supply container 4 is transferred to the pipelines L3 and L5. After passing through L7, the pump unit 20 is introduced. The photosensitive liquid pumped by the pumping operation of the pump unit 20 is provided to the filter unit 30 through the pipelines L8 and L9. The filter unit 30 removes bubbles by filtering the provided photosensitive liquid and provides the filter to the output pipeline L10. The photosensitive liquid output from the output pipeline L10 of the filter unit 30 is applied to the upper portion of the wafer 100 through the nozzle 90. When the amount of the photosensitive liquid stored in the supply container 4 gradually decreases and remains by a certain threshold amount, bubbles start to be filled inside the first trap tank 10. When the amount of bubbles is increased to a predetermined amount or more, a detection signal generated by the sensing operation of the bubble detection sensor 14 is generated. Accordingly, the controller recognizes that it is time to replace the supply container 4 with a new container 3, and generates a drive control signal for opening the tank open valve 13 and turning off the tank open valve 12. Accordingly, the tank open valve 13 is opened, while pressurized nitrogen gas is applied to the supply vessel 3 at a constant pressure through the pipeline 6. By the pressurization of the nitrogen gas, bubbles existing in the pipeline L2 and the second tank 11 are discharged to the outside through the drain line L21.

Here, micro bubbles are generated when the container replacement is detected by the photosensitive liquid empty detection, and the generated bubbles are accumulated and included in the filter unit 30, thereby causing poor photoresist coating. Bubbles collected in the filter housing of the filter unit 30 are drained because the photoresist and bubbles, which are photoresist, are drained by the operator stopping the equipment and manually opening the photoresist filter housing drain.

The main path through which the micro bubbles are generated will be described below. For example, at the emptying of the supply container 4, the worker connects the nitrogen line 6 to the connector which is attached to the standby supply container 3 so that the photosensitive liquid is pressurized by nitrogen gas. In addition, the operator manually opens the drain valve of the second trap tank 11 so that the photoresist and bubbles are drained through the drain line L21. Bubbles are generated in the second trap tank 11 during this operation.

In addition, in the process of closing the tank open valve 12 and opening the tank open valve 13, bubbles are generated by the solenoid valve constituting the tank open valve. When the micro bubbles generated in the solenoid valve are accumulated in the photoresist pipeline and the bubbles are not completely filtered by the filter unit 30, the photoresist containing bubbles is injected in the spin coating process in which the photoresist is applied to the entire surface of the wafer. Poor coating of the photoresist due to lack may occur.

As described above, in the related art, bubbles have been mixed in the photosensitive liquid dispensed to the wafer through the nozzle to reduce the flow rate, and thus there has been a problem in that the work loss and the reliability of the process are reduced due to the poor coating of the photosensitive film.

Accordingly, it is an object of the present invention to provide a photosensitive liquid supply apparatus that can solve the above-mentioned conventional problems.

Another object of the present invention to provide a photosensitive liquid supply method and a photosensitive liquid supply apparatus for minimizing or reducing the bubbles contained in the photosensitive liquid in the photosensitive liquid coating process.

Still another object of the present invention is to provide a photosensitive liquid supplying method and a photosensitive liquid supplying device capable of maximally suppressing the amount of micro bubbles flowing into a pumping line when the supply container is replaced.

Still another object of the present invention is to provide a photosensitive liquid supply apparatus and a supplying method thereof, which can optimally save the amount of photosensitive liquid discarded for bubble drain.

According to an embodiment of the present invention for achieving the above objects, the photosensitive liquid supply apparatus, the first and second supply vessel having an inner space for containing the photosensitive liquid; An integrated trap tank for trapping the photosensitive liquid supplied from one of the supply containers so that the supply of the photosensitive liquid is uniform; A pump unit for pumping the photosensitive liquid stored in the integrated trap tank to a pumping output stage; A filter unit for filtering the photosensitive liquid pumped from the pumping output end of the pump unit; A supply state monitoring unit installed in pipelines between the integrated trap tank and the supply vessels to detect an empty state of the photosensitive liquid and to switch the supply of the photosensitive liquid to a supply vessel in the standby state of the supply vessels upon detection; It is characterized by.

Preferably, a tank level sensor unit may be further installed in the integrated trap tank to detect the level of the photosensitive liquid, and the tank level sensor unit determines the level of the photosensitive liquid as a low level, a medium level, or a high level. In order to have three level sensors.

Preferably, the supply state monitoring unit, an empty detection sensor installed in the pipelines between the supply vessel for detecting the empty state of the photosensitive liquid; It may include a solenoid valve for switching the container is installed in the pipeline between the empty detection sensor and the integrated trap tank is turned on or off upon receiving the valve drive control signal.

Also, preferably, when the level of the photosensitive liquid is sensed as a medium level in the container replacement mode, pressurized nitrogen is supplied to a supply container, and the drain is opened so that bubbles contained in the photosensitive liquid in the integrated trap tank are drained to the outside. At the time of sensing, the drain open state may be switched to the drain closed state and the pressurized nitrogen supplied to the supply container may be blocked. Preferably, the photoresist may be a photoresist applied on the wafer.

In addition, the photosensitive liquid supply method according to an embodiment of the present invention, the step of storing the photosensitive liquid supplied from the supply container in one integrated trap tank; Detecting an empty state through an empty detection sensor installed in the supply container, closing the first container switching solenoid valve, and opening a second container switching solenoid valve connected to the supply container being replaced; Supplying pressurized nitrogen to the replaced supply container until the level of the photosensitive liquid stored in the integrated trap tank is sensed as a medium level, and draining open the bubbles contained in the photosensitive liquid in the integrated trap tank to drain to the outside; Switching the drain open state to the drain closed state and blocking the pressurized nitrogen supplied to the supply container when the level of the photoresist is detected as a high level; Pumping the photosensitive liquid from the integrated trap tank to a pumping output stage; Filtering the bubbles contained in the pumped photosensitive liquid and then dispensing through a nozzle.

According to the above apparatus and method configuration, bubbles generated in the trap tank are reduced and waste photoresist is reduced. In addition, since the amount of bubbles contained in the photosensitive liquid at the time of supply of the photosensitive liquid is minimized or reduced, defects due to insufficient flow rate are reduced, and thus the coating uniformity of the photosensitive liquid is improved. Therefore, the probability of pattern defects on the wafer surface can be lowered.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment of the photosensitive liquid supply apparatus and the supply method according to the present invention. Although shown in different drawings, components that perform the same or similar functions are represented by the same reference numerals.

In the case of the present invention, a single integrated trap tank is employed to reduce photoresist such as bubbles generated in the trap tank and photoresist discarded through the trap tank when the supply container is replaced. In addition, a photosensitive liquid empty sensor and a solenoid valve for switching a container are installed in the pipeline of the supply container in order to minimize waste elements of the photosensitive liquid and to reduce application failure due to a lack of flow rate. Therefore, even if bubbles are generated in the solenoid valve when the container is replaced, most of them are discharged through the drain line of the integrated trap tank so that they are not dispensed through the nozzle.

2 is a view of a photosensitive liquid supply apparatus according to an embodiment of the present invention. Referring to the drawings, unlike FIG. 1, it is shown that one integrated trap tank 50 is installed.

Specifically, the photosensitive liquid supply device shown in FIG. 2 includes a first and second supply containers 3 and 4 having an inner space for receiving the photosensitive liquid and the photosensitive liquid supplied from one of the supply containers 3 and 4. Integrated trap tank 50 to trap the supply of the photosensitive liquid uniformly, the pump unit 20 for pumping the photosensitive liquid stored in the integrated trap tank 50 to the pumping output stage (L8), and the pump unit Filter unit 30 for filtering the photosensitive liquid pumped from the pumping output stage (L8) of the (20), and the pipelines (L1, L2) between the integrated trap tank 50 and the supply vessels (3, 4) And a supply state monitoring unit configured to detect an empty state of the photosensitive liquid and to switch the supply of the photosensitive liquid to a supply container in the standby state during the detection.

Here, the supply state monitoring unit is installed in the pipelines (L1, L2) of the supply vessels empty detection sensors 40, 41 for detecting the empty state of the photosensitive liquid, and the empty detection sensor 40, 41) and a vessel switching solenoid valve 42 or 43 installed in the pipelines L3 and L4 between the integrated trap tank and turned on or off upon receipt of a valve drive control signal.

In the figure, the tank level sensor unit installed in the integrated trap tank 50 for sensing the level of the photosensitive liquid, the three level sensor 56 to determine the level of the photosensitive liquid to the low level, medium level, high level state , 55,54).

In the container replacement mode, when the level of the photosensitive liquid is sensed as the intermediate level by the level sensor 55, the pressurized nitrogen is supplied to the supply container 3 through the line 6 and the photosensitive liquid in the integrated trap tank 50. The drain valve 52 is opened so that the bubbles contained in it are drained to the outside.

When the level of the photosensitive liquid is detected by the level sensor 54 at a high level, the drain valve 52 is automatically closed to switch the drain open state to the drain closed state and is supplied to the supply container 3. The pressurized nitrogen is automatically shut off. Therefore, the waste factor of the photosensitive liquid is reduced. Here, the photoresist may be a photoresist applied on the wafer when used in the spin coater process.

Hereinafter, a photoresist flowing process according to the configuration of FIG. 2 will be described as an example. First, assuming that the photosensitive liquid 5 contained in the supply container 4 of the supply containers 3 and 4 is applied onto the wafer 100, the container open valve 43 of the container open valves 42 and 43 is applied. ) Is in a closed state, and the container open valve 42 is in an open state. Here, opening and closing operations of the container open valves 42 and 43, which may be of a solenoid valve type, may be performed by the controller when the controller of the photosensitive liquid supply device (not shown) senses an emptyness of the photosensitive liquid. Can be controlled. When the pump in the pump unit 20 performs the pumping operation, the photosensitive liquid temporarily stored in the integrated trap tank 50 through the pipeline L1 connected to the supply container 4 passes through the pipelines L7. It enters into the pump part 20. The photosensitive liquid pumped by the pumping operation of the pump unit 20 is provided to the filter unit 30 through the pipelines L8 and L9. The filter unit 30 removes bubbles by filtering the provided photosensitive liquid and provides the filter to the output pipeline L10. The photosensitive liquid output from the output pipeline L10 of the filter unit 30 is applied to the upper portion of the wafer 100 through the nozzle 90. When the amount of the photosensitive liquid stored in the supply container 4 gradually decreases and remains by a certain threshold amount, bubbles start to be filled inside the supply container 4. When the amount of bubbles is increased to a predetermined amount or more, a detection signal generated by the sensing operation of the bubble detection sensor 40 is generated. Accordingly, the controller recognizes that it is time to replace the supply container 4 with a new container 3, and generates a drive control signal for opening the container open valve 43 and turning off the container open valve 42. Accordingly, the container open valve 43 is opened, while pressurized nitrogen gas is automatically applied to the supply container 3 at a constant pressure through the pipeline 6. By the pressurization of the nitrogen gas, bubbles existing in the pipeline L2 and the integrated trap tank 50 are discharged to the outside along the drain line L20 by the drain valve 52 which is automatically opened.

The photosensitive liquid supply method described above is summarized as follows.

After storing the photosensitive liquid supplied from the supply container in one integrated trap tank 50, the empty state detection sensor 40 through the empty detection sensor 40 installed in the supply container and the first container switching solenoid valve 42 ) And the opening of the second container switching solenoid valve 43 connected to the supply container (3) to be replaced is performed. Subsequently, pressurized nitrogen is supplied to the replaced supply container 3 until the level of the photosensitive liquid stored in the integrated trap tank 50 is sensed by the level sensor 55 and the integrated trap tank 50 Drain-opening is performed so that the bubbles included in the photosensitive liquid therein are drained to the outside along the drain line L20. When the level of the photosensitive liquid is sensed as high by the level sensor 54, the drain open state is switched to the drain closed state and the pressurized nitrogen supplied to the supply container 3 is blocked. Subsequently, pumping the photoresist from the integrated trap tank to the pumping output stage (L8), filtering the bubbles contained in the pumped photoresist and dispensing through a nozzle is performed.

In the embodiment of the present invention, a bubble generated in the trap tank at the time of replacement of the supply container by adopting one integrated trap tank and installing a photosensitive liquid empty sensor and a container switching solenoid valve in the pipeline of the supply container. And photoresist such as photoresist discarded through the trap tank is reduced. As a result, the waste factor of the photosensitive liquid is minimized and the coating failure due to the lack of flow rate is reduced. In addition, even if bubbles are generated in the solenoid valve, they are mostly discharged through the drain line of the integrated trap tank.

The empty sensors have a function of detecting bubbles generated in the first and second supply containers 3 and 4, respectively, and emit light in order to more accurately detect minutely generated micro bubbles. It may be formed of a close proximity sensor other than the type having the light receiving unit.

In the above-described embodiment of the present invention, the photoresist coating process is exemplified, but is applicable to an HMDS solution coating process or a dielectric coating process. The dielectric coating device for applying a chemical solution such as Oka diffusion source (OCD) chemical to form a dielectric film such as a spin on glass (SOG) film or a field oxide film (Fox) to perform a dielectric film coating process is the coater. May correspond to

In the above description, the embodiments of the present invention have been described with reference to the drawings, for example. However, it will be apparent to those skilled in the art that the present invention may be variously modified or changed within the scope of the technical idea of the present invention. . For example, it is a matter of course that the configuration or shape of the trap tank and sensors and the installation position can be changed in different cases.

As described above, according to the present invention, bubbles generated in the trap tank are reduced and waste of photoresist is reduced. In addition, since the amount of bubbles contained in the photosensitive liquid at the time of supply of the photosensitive liquid is minimized or reduced, defects due to insufficient flow rate are reduced, and thus the coating uniformity of the photosensitive liquid is improved. Therefore, the probability of pattern defects on the wafer surface can be lowered, so that the loss of the manufacturing process is reduced and the reliability of the photoresist coating process is increased.

Claims (8)

In photoresist supply: First and second supply vessels having an inner space accommodating the photosensitive liquid; An integrated trap tank for trapping the photosensitive liquid supplied from one of the supply containers so that the supply of the photosensitive liquid is uniform; A pump unit for pumping the photosensitive liquid stored in the integrated trap tank to a pumping output stage; A filter unit for filtering the photosensitive liquid pumped from the pumping output end of the pump unit; A supply state monitoring unit installed in pipelines between the integrated trap tank and the supply vessels to detect an empty state of the photosensitive liquid and to switch the supply of the photosensitive liquid to a supply vessel in the standby state of the supply vessels upon detection; Photosensitive liquid supply device characterized in that. The photosensitive liquid supply apparatus according to claim 1, further comprising a tank level sensor unit installed in the integrated trap tank for sensing the level of the photosensitive liquid. The photosensitive liquid supply apparatus according to claim 2, wherein the tank level sensor unit has three level sensors to determine the level of the photosensitive liquid as a low level, a medium level, and a high level. According to claim 1, The supply state monitoring unit, An empty detection sensor installed in pipelines between the supply vessels to detect an empty state of the photosensitive liquid; And a solenoid valve for switching a container installed in a pipeline between the empty detection sensor and the integrated trap tank, the solenoid valve being switched on or off upon receiving a valve driving control signal. The method of claim 3, wherein when the level of the photosensitive liquid is sensed as a medium level in the container replacement mode, the pressurized nitrogen is supplied to a supply container and the drain is opened to drain the bubbles contained in the photosensitive liquid in the integrated trap tank to the outside. The photosensitive liquid supply device, characterized in that for switching the drain open state to the drain closed state and to cut off the pressurized nitrogen supplied to the supply container. The photosensitive liquid supply apparatus of claim 1, wherein the photosensitive liquid is a photoresist applied to an upper portion of a wafer. In the photosensitive liquid supply method: Storing the photosensitive liquid supplied from the supply container in one integrated trap tank; Detecting an empty state through an empty detection sensor installed in the supply container, closing the first container switching solenoid valve, and opening a second container switching solenoid valve connected to the supply container being replaced; Supplying pressurized nitrogen to the replaced supply container until the level of the photosensitive liquid stored in the integrated trap tank is sensed as a medium level and drain-opening the bubbles contained in the photosensitive liquid in the integrated trap tank to be drained to the outside; Switching the drain open state to the drain closed state and blocking the pressurized nitrogen supplied to the supply container when the level of the photoresist is detected as a high level; Pumping the photosensitive liquid from the integrated trap tank to a pumping output stage; And dispensing through the nozzle after filtering the bubbles contained in the pumped photosensitive liquid. 8. The method of claim 7, wherein the bubbles are micro bubbles mainly generated when the supply container is replaced.

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