JPH0568095B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention discharges a chemical solution used in a side rinsing process in which a solvent is applied to an insulating coating on the periphery of a wafer to dissolve it in a photoetching process of a semiconductor integrated circuit manufacturing process. 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. Although side rinsing as described above is performed, conventionally, a bellows pump or pressure feeding using an inert gas has been used to discharge the solvent.

Problems to be Solved by the Invention However, in such a discharging method, a large amount of solvent is temporarily discharged at the moment the valve is opened, and as it bounces off the wafer, it adheres to the insulating coating on other parts. If the pressure is adjusted to a low level that prevents splashing, the flow rate necessary for side rinsing cannot be obtained. It was hot.

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

Means for Solving the Problems The chemical liquid dispensing device of the present invention solves the above problems by using 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 configuration, and the control device can arbitrarily adjust the supply air pressure of the pressurized air supply device, thereby arbitrarily controlling the operating pressure of the diaphragm pump.

Therefore, the minimum pressure and maximum pressure of the chemical liquid discharged from the chemical liquid nozzle and the time from the minimum pressure to the maximum pressure can be arbitrarily controlled, for example,
By controlling the pressure to be low at the start of ejection and gradually increasing the pressure, splashing can be prevented and the chemical liquid can be ejected under the best conditions.

Embodiment Hereinafter, an embodiment of the present invention will be described based on the accompanying drawings.

In FIG. 1, 1 is a tank containing a chemical solution, into which a suction pipe 2 is inserted, and an air-driven first on-off valve 3 is interposed in the suction pipe 2. . 4 is an air-driven diaphragm pump equipped with a diaphragm 4a, to which a suction pipe 2 and a discharge pipe 5 are connected,
An air-driven second on-off valve 7 is interposed in the discharge pipe 5, and 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 4a, a vacuum generator that applies negative pressure to the lower surface of the diaphragm 4a, and first and second on-off valves 3, 7 drive pneumatic valve 10,1
1 is built-in, and this pneumatic output section 8 is electrically controlled by a control device 9.

Next, the operation of this embodiment will be explained.

First, close one pneumatic valve 11 of the pneumatic output section,
The supply of pressurized air to the second on-off valve 7 is cut off to close it, and the other pneumatic valve 10 is opened, and the first
When pressurized air is supplied to the on-off valve 3 and the valve is closed, when the vacuum generator is activated to create a negative pressure on the lower surface side of the diaphragm 4a, the diaphragm 4a
is curved downward and the volume on the upper surface side increases, so the chemical solution in the tank 1 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 operated, pressurized air with a pressure proportional to the magnitude of the electric signal input 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 electrical signal input 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 maintained for a while and then gradually lowered, and the speed at which the chemical solution is discharged from the nozzle 6 can be controlled depending on the range of this pressure change in which the second on-off valve 7 is closed. In the side rinsing process described above, the solvent is initially discharged at a low pressure and then gradually raised to a high pressure to prevent splashing due to rapid discharge at the initial stage of opening the valve, and The flow rate necessary for side rinsing can be secured, the generation of defective products due to the splashing of the solvent can be prevented, and side rinsing can be performed reliably.

In this embodiment, the diaphragm pump 4 is connected to the diaphragm pump 4 through an electropneumatic proportional valve by an electric signal emitted from a control device 9.
By controlling the discharge pressure of the nozzle 6 and selecting the opening timing of the second on-off valve 7, the discharge speed of the chemical solution from the nozzle 6 can be arbitrarily controlled. It can be used not only for discharging a liquid (chemical solution for photoetching), but also for discharging a general chemical solution.

[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. 1: Tank, 4: Diaphragm pump, 6: Nozzle, 8: Pneumatic output section (pressurized air supply device),
9: Control device.

Claims (1)

[Claims] 1 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, and an electrically controlled air supply pressure of the pressurized air supply device. What is claimed is: 1. A chemical liquid ejection device comprising: a control device for controlling the liquid chemically;