JPH0458520A - Chemical discharger - Google Patents

Abstract

PURPOSE:To optionally control the working pressure of a diaphragm pump so as to discharge chemicals under the best condition by electrically controlling the air pressure supplied by a pressure air feeder. CONSTITUTION:When the pressure on the bottom side of a diaphragm 4a is made negative in the condition that one pneumatic valve 11 of a pneumatic output part 8 is closed and a second opening/closing valve 7 is closed and that the other pneumatic valve 10 is opened and a first opening/closing valve 3 is opened, the bottom side of a diaphragm 4a curves, and the chemical liquid inside a tank 1 is drawn up and fills the upper side of the diaphragm 4a. Next, when an electropneumatic valve is operated at the same time when the first opening/closing valve 3 closes, the air pressurized in proportion to the magnitude of the electric signal inputted from a controller 9 works on the bottom of the diaphragm 4a, and pressurizes, at the same pressure, the chemicals on the topside. Hereby, the discharge speed of the chemical from a nozzle 6 can optionally be controlled.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention discharges a chemical solution used in a photoetching process in the manufacturing process of semiconductor integrated circuits, such as a site rinsing process in which a solvent is applied to an insulating coating on the periphery of a wafer to dissolve it. Regarding equipment.

Conventional technology For example, when handling a wafer, the insulating coating on the periphery may peel off and adhere to the substrate, resulting in a defective product. Conventionally, pressurized pressure feeding using a bellows pump or an inert gas was used for this purpose.

Problems to be Solved by the Invention However, with this type of dispensing method, a large amount of solvent is temporarily dispensed at the moment the valve is opened, and as it bounces off the wafer, it may adhere to the insulating coating on other parts. There is a problem that defective products may be produced if the part is melted or the width is melted more than necessary.Also, if the pressure is adjusted to a low level that does not cause rebound, there is a problem that the flow rate required for side rinsing cannot be obtained. Ta.

Incidentally, such a problem may also occur when discharging chemical liquids other than side rinse.

Means for Solving the Problems The chemical liquid dispensing device of the present invention, as a means for solving such problems, includes an air-driven diaphragm pump connected to a chemical liquid tank and a chemical liquid nozzle, and the diaphragm pump. The configuration includes a pressurized air supply device that supplies driving pressurized air, and a control device that electrically controls the air pressure supplied by the pressurized air supply device.

Functions and Effects The present invention has the above-mentioned configuration, and the supply air pressure of the pressurized air supply device can be arbitrarily adjusted by the control device.
This makes it possible to arbitrarily control the operating pressure of the diaphragm pump.

Therefore, it is possible to arbitrarily control the minimum pressure and maximum pressure of the chemical liquid discharged from the chemical liquid nozzle, as well as the time from the minimum pressure to the maximum pressure. For example, the pressure may be kept low at the start of discharge, and then controlled to gradually increase to a high pressure. By doing so, splashing can be prevented, and the medicinal liquid can be ejected under the best conditions.

EXAMPLE Hereinafter, an example of the present invention will be described based on the accompanying drawings.

In FIG. 1, 1 is a tank containing a chemical solution,
A suction pipe 2 is inserted into the suction pipe 2, and an air-driven first on-off valve 3 is interposed in the suction pipe 2. Reference numeral 4 denotes an air-driven diaphragm pump equipped with a diaphragm 4a, to which a suction pipe 2 and a discharge pipe 5 are connected.A second air-driven on-off valve 7 is connected to the discharge pipe 5. A nozzle 6 is connected to the tip. 8
is a pneumatic output section, which includes an electropneumatic proportional valve that supplies pressurized air to the lower surface of the diaphragm 42L, a vacuum generator that makes the lower surface of the diaphragm 4a a negative pressure, and the first and second on-off valves 3.
．． It has built-in pneumatic valves 10 and 11 for driving 7.
This pneumatic output section 8 is electrically controlled by a control 5 device 9.

Next, the operation of this embodiment will be explained.

First, one pneumatic valve 11 of the pneumatic output section is closed, the supply of pressurized air to the second on-off valve 7 is cut off, and the valve is closed, and the other pneumatic valve IO is opened, and the first on-off valve 3 is closed. When pressurized air is supplied to the valve and the valve is opened, when the vacuum generator is activated to create a negative pressure on the bottom side of the diaphragm 4a, the diaphragm 4a curves downward and the volume on the top side increases. The chemical liquid in the tank I is sucked up and fills the upper surface side of the diaphragm 4a. Here, when the first on-off valve 3 is closed, the vacuum generator is stopped, and the electro-pneumatic proportional valve is activated, pressurized air at a pressure proportional to the magnitude of the electric signal manually inputted from the control device 9 is supplied to the diaphragm. It acts on the lower surface of 4a and pressurizes the chemical solution on the upper surface with the same pressure. The pressure applied to the chemical liquid is proportional to the magnitude of the electric signal manually applied to the electropneumatic proportional valve. For example, as shown in Figure 2, the initial pressure is low and then gradually increased to reach the maximum value. The pressure can be controlled to be maintained for a while and then gradually lowered, and in which range of this pressure change the second
The discharge speed of the chemical solution from the nozzle 6 can be arbitrarily controlled by closing the on-off valve 7. In the side rinsing process described above, the solvent is initially discharged at a low pressure and then gradually raised to a high pressure. By doing so, it is possible to prevent splashing caused by rapid discharge at the initial stage of opening the valve, and to secure the flow rate necessary for side rinsing. You can do it for sure.

In this embodiment, the discharge pressure of the diaphragm pump 4 is controlled via the electropneumatic proportional valve by an electric signal issued from the control device 9, and the opening timing of the second on-off valve 7 is selected. The discharge speed of the chemical solution can be controlled arbitrarily, and it can be used not only for side rinsing but also for dispensing resist solution (chemical solution for photo-etching). can also be used.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an embodiment of the present invention, and FIG. 2 is a graph showing changes in discharge pressure. 14 Tank 4: Diaphragm pump 6: Nozzle 8
・Pneumatic output section (pressurized air supply device) 9: Control device applicant: CKD Co., Ltd.

Claims (1)

[Claims] An air-driven diaphragm pump connected to a chemical liquid tank and a chemical liquid nozzle; a pressurized air supply device that supplies pressurized air to drive the diaphragm pump; A chemical liquid dispensing device characterized in that it is equipped with a control device that controls the