JPH05315314A - Method for stirring processing liquid for substrate and equipment for processing liquid for substrate - Google Patents

Abstract

PURPOSE:To prevent mixing of foreign objects in liquid by moving and stirring liquid through the blowing pressure of gas on the surface of developing liquid or etching liquid, in which a substrate is dipped. CONSTITUTION:When an inert gas such as nitrogen blows out on the surface of developing liquid from a gas blowing nozzle 6, the surface of liquid in the region is leveled down by injection power of the inert gas, and liquid surrounding the region is moved and stirred. If the gas nozzle is moved, developing liquid is replaced remarkably. Therefore, development is made smoothly without stagnation of product materials generated by developing liquid. There is no occurrence that metal or other polluted materials are mixed in the liquid, and there is also no trouble of ununiformity of developing. As a result, sticking of foreign objects or bubble can be prevented, and the yield can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of stirring a substrate processing liquid and a substrate liquid processing apparatus. More specifically, the present invention relates to a method for agitating a substrate processing solution including a solution processing step using a photoresist developing solution or an etching solution, and a substrate solution processing apparatus used for semiconductor device formation, mask formation, and the like.

[0002]

2. Description of the Related Art A liquid is used in the process of manufacturing a semiconductor device, an exposure mask, a reticle, etc., for example, when developing a photoresist or etching a film.

When developing or etching, these liquids are generally agitated in order to eliminate development unevenness and etching unevenness and to make the temperature distribution uniform.

As a stirring method, as shown in FIG. 3 (a), a screw 32 is put in a dip tank 31 and rotated by a motor 33, or as shown in FIG. 3 (b), a dip is used. A method such as bubbling by supplying gas into the liquid in the tank 34 is adopted.

Reference numeral 35 in the figure denotes a substrate to be processed, and 36 denotes a chuck for mounting the substrate to be processed.

[0006]

However, the screw 3
When agitated by 2, the dust accompanying the rotation is mixed into the liquid and contaminates the developing solution and the etching solution to damage the film on the substrate 35 to be processed, or the dust adheres to the surface of the substrate 35 to be processed and is processed. It becomes an obstacle. Further, according to the bubbling, bubbles adhere to the surface of the substrate 35 to be processed, and the processing of that portion does not proceed.

Therefore, there is a problem in that development and etching become insufficient, leading to a decrease in yield and deterioration of device characteristics. The present invention has been made in view of such a problem, and provides a method for manufacturing a semiconductor device and a substrate liquid processing apparatus capable of forming a device having good characteristics by preventing foreign matter from entering the liquid and improving yield. The purpose is to provide.

[0008]

The above-mentioned problems are characterized by including a step of spraying a gas onto the surface of a liquid for immersing a substrate to be processed and stirring the liquid, as illustrated in FIG. This is achieved by a method of stirring the substrate processing liquid.

Further, the above gas is achieved by a method of stirring a processing liquid for a substrate, which has a property of not reacting with the liquid and does not contain a contaminant. Alternatively, a dip tank (1) containing a liquid (D) for immersing a substrate (W) to be processed, and a gas jet nozzle (6) for stirring the liquid are arranged above the dip tank (1). This is achieved by the substrate liquid processing apparatus.

Further, the gas jet nozzle is arranged so that it can be moved or the jet angle can be changed.

[0011]

[Operation] According to the present invention, a gas is blown onto the surface of a liquid such as a developer or an etching liquid for immersing a substrate, and the pressure moves the liquid to stir it.

Therefore, foreign matter and bubbles are prevented from adhering to the surface of the substrate to be processed, yield is improved, and deterioration of devices formed on the substrate to be processed is prevented. In this case, if a gas that does not react with the liquid and does not contain a contaminant is used, the liquid will not be contaminated or the properties will not change, and the processing will proceed normally.

Further, according to the present invention, since the gas jet nozzle 6 is arranged on the liquid contained in the dip tank 1, the liquid is not contaminated by the stirrer. Moreover,
Since the gas ejection nozzle 6 can be moved and the ejection angle thereof can be changed, the optimum condition of the stirring state can be set according to the property of the liquid and the processing content, and the yield can be further improved.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

In the figure, reference numeral 1 is a drain port 2 at the center of the bottom.
A spin chuck 3 in which a semiconductor device and a substrate W for forming a reticle are mounted.
And a supporting rod 4 which is movable up and down and is rotatable through the drainage port 2 is attached to the bottom of the spin chuck 3.

On the bottom surface of the spin chuck 3, around the support rod 4, a closing portion 5 for closing the drainage port 2 is formed, and by moving the spin chuck 3 up and down, the drainage port 2 is formed. Is configured to be opened and closed by the closing portion 5.

Reference numeral 6 denotes a gas injection nozzle which is arranged above the dip tank 1 so as to be movable by a moving mechanism 7. The inert gas such as Ar or N ₂ supplied from the gas supply source 8 is stored in the dip tank 1 within the dip tank 1. The surface of the liquid D is sprayed to stir the liquid D.

Further, a liquid supply pipe 9 for supplying a photoresist developing solution, an etching liquid, etc. is arranged near the periphery of the dip tank 1, and a rinse nozzle for supplying a rinse liquid is provided above the dip tank 1. Ten are arranged.

The gas jetted from the gas jet nozzle 6 is not limited to the inert gas, but may be any gas as long as it has a property of not reacting with the liquid. next,
The operation of the above-described embodiment will be described.

In the above-mentioned embodiment, the substrate W is a reticle dry plate which is an original plate of a semiconductor device, and a photoresist F is applied on the upper part of the reticle dry plate.
A photoresist developing solution is contained therein.

First, the substrate W is placed without the developer in the dip tank 1 with the exposed photoresist surface facing up.
After mounting on the spin chuck 3,
Is lowered and the drainage port 2 of the dip tank 1 is closed by the closing portion 5 on the lower surface side. This state is the developing position.

Then, the developer is supplied from the liquid supply pipe 9,
The photoresist F on the substrate W is immersed in the developing solution for development. In this case, the photoresist F is placed almost along the liquid surface.

When the development is started, there is a portion where the amount of the photoresist F dissolved in the developer is large and a portion where the amount of the photoresist F is dissolved is small, and a difference in the amount of the dissolved photoresist F occurs depending on the region. Therefore, when an inert gas such as nitrogen is jetted from the gas jet nozzle 6 to the surface of the developing solution, the jetting force lowers the liquid level in that area, and the liquid around the area moves and is agitated.
Then, when the gas nozzle is moved, the developer is largely replaced along the moving path, so that the product produced by the development is not stagnant and the development is smoothly performed. Moreover, since the developing solution is agitated by the gas, contaminants such as metals are not mixed in the solution, and uneven development is not hindered.

After the development of the photoresist F is completed, the support rod 4 is raised to lift the spin chuck 3 and the substrate W is set to the rinse position. Due to this rise, the closed portion 5 of the spin chuck 3 separates from the drainage port 2, and the developer flows down from there.

After that, the rinse liquid is sprayed from the rinse nozzle 10 by a spray method to perform the rinse. At this time, the spin chuck 3 is rotated via the support rod 4. After the rinsing is completed, the substrate W is rotated together with the spin chuck 3 to dry its surface.

After drying, the substrate W is loaded from the spin chuck 3 and the process is completed. By the way, in the above-mentioned embodiment, the liquid to be put in the dip tank 1 has been described as the developing liquid.
When the treatment is performed by adding the other liquid, the stirring is similarly performed.

In this case, the gas flow rate is changed in consideration of the viscosity of the liquid, the method of filling the liquid, etc., but the size is, for example, about 5 l / min or less. If the flow rate is too high, the developer may scatter or there may be no liquid, or
Since bubbles tend to be slightly generated in the liquid, adjustment is necessary.

Further, when the viscosity of the liquid is small, the liquid is easily moved by the jet of gas, and the stirring efficiency is improved.
The jet direction of the gas may be substantially perpendicular to the stationary liquid surface, but if the gas is sprayed obliquely to the liquid surface, the stirring efficiency will be further improved. In this case, as shown in FIG. 2 (a), spraying along the side wall of the dip tank 1 or spraying in the center of the dip tank 1 as shown in FIG. Efficiency is improved.

Of course, if dust or contaminants are contained in the gas, they will penetrate into the liquid, resulting in defects such as development and etching. Therefore, it is desirable that the blown gas be sufficiently purified.

Next, an example of the test results will be given. (Test 1) In the first sample, when a positive photoresist is applied to the substrate W and a pattern of 1 μm is formed on the substrate W, the ratio of the total area of the exposed region A and the non-exposed region B is 9: 1.
The ratio is. The second sample has a ratio of the total area of the exposed area A to the non-exposed area B of 1: 1.

As a result of developing the photoresists of the first sample and the second sample according to the present invention, the pattern size difference between Sample 1 and Sample 2 was 0.02 μm. On the other hand, when the photoresist of the first sample and the second sample was developed without using a stirrer, the pattern size of the first sample became smaller than the pattern size of the second sample,
The dimensional difference was 0.05 μm.

This is because when the exposed area is large and the dissolved portion of the photoresist by the developing solution is large, the dissolved substance is stagnant and the supply of new developing solution is hindered without stirring according to the present invention. It is considered that development is difficult to proceed.

Each pattern size difference is an average value of the three-sheet processing. (Test 2) A negative photoresist is coated on a 125 mm × 125 mm substrate, and a 1 μm line &
Expose a pattern of spaces.

And a product developed using the present invention,
The pattern defects of the photoresist without stirring were examined. According to the present invention, the number of defects is 0.3 / sheet in the area of 50 mm × 50 mm, and 0.53 when the liquid is not stirred.
It was found that the number of defects was reduced to 0.23 defects / sheet by the present invention.

The test was conducted on 10 sheets each.

[0036]

As described above, according to the present invention, a gas is blown to the surface of a liquid such as a developing solution or an etching solution for immersing a substrate, and the pressure moves the solution to stir it. It is possible to prevent foreign matters and bubbles from adhering to the surface of the substrate to be processed, improve the yield, and prevent deterioration of devices formed on the substrate to be processed.

In this case, when a gas that does not react with the liquid and does not contain contaminants is used, the liquid will not be contaminated or the properties will not change, and the process will proceed normally and the yield can be increased.

Further, according to the present invention, since the gas ejection nozzle is arranged on the liquid contained in the dip tank, the liquid is not contaminated by the stirrer. Moreover, since the gas ejection nozzle can be moved and the ejection angle can be changed, the optimum condition of the stirring state can be set in accordance with the property of the liquid and the processing content, and the yield can be further improved. ..

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is an operation explanatory diagram showing an embodiment of the present invention.

FIG. 3 is a configuration diagram showing an example of a conventional device.

[Explanation of symbols]

 1 Dip Tank 2 Waste Liquid Port 3 Spin Chuck 4 Support Rod 5 Closure 6 Gas Injection Nozzle 7 Moving Mechanism 8 Gas Supply Source 9 Liquid Supply Pipe 10 Rinse Nozzle

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hideyuki Kanemitsu 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited (72) Inventor, Akira Takano 110-1 Shimoasao, Aso-ku, Kawasaki City, Kanagawa Prefecture In the company

Claims (4)

[Claims] 1. A method of stirring a processing liquid for a substrate, which comprises a step of blowing a gas onto a surface of a liquid for immersing a substrate to be processed and stirring the liquid. 2. The method for stirring a substrate processing liquid according to claim 1, wherein the gas has a property of not reacting with the liquid and does not contain a contaminant. 3. A dip tank (1) containing a liquid (D) for immersing a substrate (W) to be processed, and a gas jet nozzle (6) for stirring the liquid above the dip tank (1). A substrate liquid processing apparatus characterized by the above. 4. The gas ejection nozzle is arranged so as to be movable or capable of changing the ejection angle.
The substrate liquid processing apparatus described.