JPH0444218Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a chemical liquid dropping device which is a semiconductor device manufacturing equipment.

BACKGROUND TECHNOLOGY When manufacturing semiconductor devices, chemical treatment is sometimes performed. Apparatuses for manufacturing semiconductor devices by chemical treatment are broadly classified into dip type and spinner type, and the latter uses a chemical dropper. In this type of chemical liquid dripping device, if the valve and filter are simply connected to the chemical liquid supply line, the chemical liquid in the nozzle will drip after the valve is closed, making the supply amount of the chemical liquid unstable, and If the nozzle moves or the workpiece, such as a semiconductor wafer, moves quickly, the surrounding area will be contaminated by dripping chemical solution.

For this reason, various measures have been taken in chemical liquid dropping devices to prevent the chemical liquid from dripping. Two examples of conventional chemical liquid dropping devices that are designed to prevent dripping of drops will be described with reference to FIGS. 2 and 3.

In FIG. 2, 1 is a tank for storing the chemical solution 2, 3 is a pipe for transporting the drug solution 2, 4 is a first valve for opening and closing the pipe, 5 is for pumping up the drug solution 2 in the tank 1, A bellows pump 6a is used to transport the chemical solution 2 in the pipe 3, and a second bellows pump 6a is used to open and close the pipe 3.
Valve 7a is a needle valve for adjusting the amount of chemical liquid 2 passing through second valve 6a, 8a is a filter for filtering dust in chemical liquid 2, and 9 is a nozzle attached to the tip of conduit 3. . One end of the pipe line 3 is immersed in the chemical solution 2 in the tank 1, and is connected in series with the first valve 4, the second valve 6a, and the filter 8a sequentially from the upstream side of the tank 1, and the end is connected to the nozzle 9. be. A bellows pump 5 is connected between the first valve 4 and the second valve 6a. Further, a needle valve 7a is connected in parallel to the second valve 6a.

Next, the operation of the prior art shown in FIG. 2 will be explained. In the first step, when the bellows pump 5 is extended from the retracted state with the second valve 6a closed and the first valve 4 opened, the chemical solution 2 is pumped into the tank 1. In the second step, when the bellows pump 5 is retracted by closing the first valve 4 and opening the second valve 6a, the pumped chemical solution 2 passes through the second valve 6a and the needle valve 7a, and then passes through the filter. 8a to the nozzle 9
dripped from. When the dropping of chemical solution 2 is completed, the third
As a step, the second valve 6a is closed and the first valve 4 is opened to extend the bellows pump 5. Then, as in the first stage, the chemical liquid 2 in the tank 1 is pumped up, and at the same time, the chemical liquid 2 is pulled back from the nozzle 9 side to the bellows pump 5 through the needle valve 7a, but at this time, the suction force of the bellows pump 5 is filter 8
Since the nozzle 9 and the filter 8a are blocked by
The chemical solution 2 in between remains as it is.

Next, the prior art shown in FIG. 3 will be explained.

In FIG. 3, 1 is a tank for storing the chemical solution 2, 3 is a pipe for transporting the drug solution 2, 4 is a first valve for opening and closing the pipe, and 5 is for pumping up the drug solution 2 in the tank 1. A bellows pump 6b is used to transport the chemical solution 2 in the pipe 3, and a second bellows pump 6b is used to open and close the pipe 3.
7b is a needle valve for adjusting the amount of chemical solution 2 passing through the second valve 6b, 8b is a filter for filtering dust in the chemical solution 2, and 9 is a nozzle attached to the tip of pipe line 3. be. One end of the pipe line 3 is immersed in the chemical solution 2 in the tank 1, and is connected in series with the first valve 4, filter 8b, and second valve 6b sequentially from the upstream side of the tank 1, and the end is the nozzle 9. . A bellows pump 5 is connected between the first valve 4 and the filter 8b. Also,
A needle valve 7b is connected in parallel with the series part of the filter 8b and the second valve 6b.

Next, the operation of the prior art shown in FIG. 3 will be explained.

In the first step, when the bellows pump 5 is extended with the second valve 6b closed and the first valve 4 opened, the chemical solution 2 in the tank 1 is pumped up. In the second step, when the bellows pump 5 is retracted with the first valve 4 closed and the second valve 6b opened, the pumped chemical solution 2 is filtered by the filter 8b, and then the second valve 6b is opened. It passes through the valve 6b or passes through the needle valve 8b without passing through the filter 8b, and is dripped from the nozzle 9. When the dropping of the chemical solution 2 is completed, in the third step, the second valve 6b is closed, the first valve 4 is opened, and the bellows pump 5 is extended. Then, as in the first stage, the chemical liquid 2 in the tank 1 is pumped up, and further, the chemical liquid 2 near the nozzle 9 is pulled back through the nozzle valve 7b and does not stay in the nozzle 9.

Problems to be Solved by the Invention When a chemical liquid dropping device is used in manufacturing semiconductor devices, it is desirable that a predetermined amount of uncontaminated chemical liquid be dropped.

However, in the conventional technique shown in FIG. 2, even after the chemical liquid dripping is finished, a pressure difference occurs between the primary side and the secondary side of the filter 8a, so the chemical liquid near the filter 8a is not pulled back, and the chemical liquid drips. If this cannot be completely prevented and more than a predetermined amount of chemical solution is dropped, or if the nozzle a moves, there is a problem that the area around the device is contaminated by the dropped chemical solution.

In the conventional technique shown in FIG. 3, the chemical liquid near the nozzle 9 is pulled back, but since the chemical liquid passes through the valve 6b after passing through the filter 8b, it is not possible to remove dust generated at the valve 6b. Since the needle valve 7b is connected in parallel to the filter 8b, some of the chemical solution passes through the needle valve 7b without passing through the filter 8b, which causes the problem that contaminated chemical solution is dripped.

Means for solving the problems Therefore, in order to solve the above problems, the present invention
A chemical solution storage tank, a pipe line having a nozzle at one end and the other end immersed in the tank, a bellows pump attached to the pipe between the tank and the nozzle, and a bellows pump installed between the bellows pump and the tank. In the chemical liquid dropping device, which pumps up the chemical liquid from the tank by retracting and extending the bellows pump and drips it from the nozzle, the second valve and the needle are connected between the nozzle and the bellows pump. It consists of a valve connected in parallel and a filter connected in series to these, the filter is connected by a first series pipe line arranged on the nozzle side, and a third valve and a second needle valve are connected. A second series conduit formed by connecting in series is connected in parallel to the first series conduit.

Function: By opening and closing the second valve and adjusting the first needle valve, the residual pressure in the filter is released and the chemical solution is pulled back properly.

The amount of liquid medicine to be drawn back is adjusted by adjusting the third valve and the second needle valve.

Furthermore, since all of the dropped chemical liquid passes through the filter, the chemical liquid is not contaminated.

Embodiment An embodiment of the present invention will be described based on FIG. 1. 1 is a tank for storing a chemical solution 2, 3 is a pipe line for transporting the drug solution 2, and a first series pipe line A is located on the way.
and the second series conduit B are connected in parallel. 4,
6c and 6d are first, second, and third valves for opening and closing the pipe line 3; 5 is a bellows pump for pumping up the chemical liquid 2 in the tank 1 and transporting the chemical liquid 2 in the pipe line 3; 7c and 7d are first and second needle valves for adjusting the amount of the chemical liquid 2 transported through the pipe 3; 8c is a filter; and 9 is a nozzle attached to the tip of the pipe 3. One end of the pipe line 3 is immersed in the chemical solution 2 in the tank 1, and sequentially from the upstream side of the tank 1, the first valve 4, and then the parallel connection of the first series pipe A and the second series pipe B. The coupling part and then the nozzle 9 are connected. A bellows pump 5 is connected to the upstream connecting portion of the first series line A and the second series line B. The first series pipe A connects the second valve 6c in series to the upstream side and the filter 8c to the downstream side,
Further, the second valve 6c is connected to the first needle valve 7c.
Connect in parallel. The second series conduit B serially connects the second needle valve 7d to the upstream side and the third valve 6d to the downstream side.

The present embodiment has the above configuration, and its operation will be explained next.

No. 1, in which no medicinal solution 2 is inhaled into conduit 3.
At this stage, the second valve 6c and the third valve 6d are closed, and only the first valve 4 is opened. When bellows pump 5 is extended in this state, tank 1
The chemical solution 2 is pumped up inside. In the next second stage, the first valve 4 is closed, the third valve 6d remains closed, and the second valve 6c is opened. When the bellows pump 5 is extended in this state, the pumped chemical solution 2 passes through the second valve 6c or the first needle valve 7c, is filtered by the filter 8c, and drips from the nozzle 9.

In the third stage after the dropping of chemical solution 2 is completed,
Close the second valve 6c, close the first valve 4 and the third valve 6c.
Extend the bellows pump 5 with the valve 6d open. By this operation, the chemical liquid 2 in the tank 1 is pumped up, and at the same time, the chemical liquid 2 near the nozzle 9 is pulled back through the third valve 6d and the second needle valve 7d, and is drawn back from the nozzle 9. Prevents chemical liquid from dripping.

When dropping the chemical solution 2 onto the semiconductor element (not shown) as the next step, both the first valve 4 and the third valve 6d are closed as in the second step,
Open only the second valve 6c. When the bellows pump 5 is retracted in this state, all of the chemical liquid 2 passes through the filter 8c, so that the clean chemical liquid is dripped onto the semiconductor element (not shown).

As described above, by repeating the first to third steps, semiconductor elements are sequentially treated with a chemical solution.

Effects of the invention According to the invention, the chemical solution dripped from the nozzle is completely filtered by the filter, so it is clean. Furthermore, after the drop is finished, the chemical liquid is pulled back from the vicinity of the nozzle, which prevents dripping. Therefore, it is possible to manufacture a high-quality semiconductor device onto which an optimum amount of clean chemical solution is dropped.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of a chemical liquid dropping device according to the present invention, and FIGS. 2 and 3 are schematic diagrams showing a conventional technique. 1...Tank, 2...Medical solution, 3...Pipeline, 4...
...First valve, 5... Bellows pump, 6c...
Second valve, 6d...Third valve, 7c...
First needle valve, 7d... second needle valve,
8c...Filter, 9...Nozzle, A...1st
B... second series pipe.

Claims (1)

[Claims for Utility Model Registration] A chemical storage tank 1, a pipe 3 having a nozzle 9 at one end and the other end immersed in the tank 1, and a pipe 3 installed between the tank 1 and the nozzle 9. It consists of a bellows pump 5 which is connected to the tank 1, and a first valve 4 provided between the bellows pump 5 and the tank 1. In the chemical liquid dripping device that drips more liquid, a first needle valve 7C and a second valve 6C are connected in parallel between the nozzle 9 and the bellows pump 5, and a filter 8C is connected in series.
connected by a series pipe A, and the third valve 6d and the second needle valve 7
d is connected in series, and a second series line B is connected in parallel to the first series line A.