JP2658653B2 - Cleaning apparatus and exhaust gas control method in cleaning apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for cleaning a piece of solid material such as a semiconductor wafer, a glass substrate or a disk substrate, and more particularly, to a method for cleaning fine frozen particles on an object to be cleaned such as a semiconductor wafer in a cleaning tank. Is washed together with a gas from a spray nozzle at a high pressure for washing.
The present invention relates to a cleaning apparatus configured to exhaust a cleaning tank and a method of controlling the exhaust in the cleaning apparatus.

[0002]

2. Description of the Related Art FIG. 3 is a schematic structural view of a conventional semiconductor wafer cleaning apparatus. In the figure, 1 is an ice making section for generating fine frozen particles, 2 is a liquid nitrogen supply pipe for cooling, 3 is a spray nozzle for spraying pure water, 4 is fine frozen particles generated in the ice making section 1, 5 Is an injection nozzle for injecting the fine frozen particles 4, 6 is a holding arm for holding a semiconductor wafer 7 as an object to be cleaned, 8 is a moving mechanism for moving the semiconductor wafer 7, 9 is a cleaning tank, 10 is an exhaust duct. , 11 is a blower for exhausting the washing tank, 14 is an automatic damper, 1
2 ₀ is a control unit for controlling each unit.

Next, the operation will be described.

Liquid ice is supplied to an ice making section 1 surrounded by a heat insulating material through a liquid nitrogen supply pipe 2 and evaporated therein, thereby cooling the inside of the ice making section 1. After the inside of the ice making section 1 is sufficiently cooled, ultrapure water is sprayed from the spray nozzle 3 to obtain fine frozen particles 4. Fine frozen particles 4 thus obtained
Is injected into the cleaning tank 9 at a high pressure by an ejector method using a gas jet. Thus, the surface of the semiconductor wafer 7 is cleaned by ejecting the fine frozen particles 4 toward the semiconductor wafer 7 held by the holding arm 6.

At the time of this cleaning, the cleaning tank 9 is evacuated by an air blower 11 to prevent the jet flow from being curled up due to the injection of the fine frozen particles 4.

[0006] Control unit 12 _0, in the above cleaning operation, the injection amount control and automatic damper 1 of the injection nozzle 5
A series of controls, such as the control of the displacement by the control unit 4, are performed.

[0007]

Problems to be Solved by the Invention FIGS. 4A and 4B
5 is a timing chart showing changes in the injection amount of the injection nozzle 5 and the exhaust amount of the cleaning tank 9 in such a conventional cleaning apparatus. As shown in FIG.
The control of the exhaust amount by the automatic damper 14 is performed in two stages of setting "large" during cleaning and "small" during stoppage.

Therefore, during cleaning, the exhaust amount is controlled to be constant regardless of the injection amount of the injection nozzle 5, and therefore, the downflow (laminar flow) of the clean room where the cleaning apparatus is installed is performed. ), And draws dust into the cleaning tank 9 to contaminate the cleaning tank 9.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is possible to reduce turbulence in downflow of a clean room in which a cleaning apparatus is installed, thereby reducing contamination caused by suction of dust into a cleaning tank. The purpose is to do.

[0010]

In order to achieve the above-mentioned object, the present invention is configured as follows.

That is, the present invention described in claim 1 provides:
In the cleaning device, in the cleaning device that cleans the object to be cleaned by injecting the fine frozen particles together with the gas at a high pressure from the injection nozzle in the cleaning tank, in order to suppress the curling of the jet by the injection of the fine frozen particles. A blower that exhausts the washing tank, an inverter that controls a rotation speed of the blower, and control of the inverter to control an exhaust amount of the blower to an exhaust amount according to an injection amount of an injection nozzle. Means.

According to a second aspect of the present invention, in the cleaning tank, fine frozen particles are jetted onto the object to be cleaned together with gas from an injection nozzle at a high pressure to wash the object to be cleaned. A method of controlling exhaust air in a cleaning apparatus that exhausts the cleaning tank in order to suppress the curling of the jet flow due to the injection of the fine frozen particles, wherein the exhaust amount of the cleaning tank is determined by the injection amount of an injection nozzle. It is controlled according to.

[0013]

According to the above arrangement, the exhaust amount of the cleaning tank is controlled to an amount corresponding to the injection amount from the injection nozzle, so that the exhaust amount is controlled to a constant amount regardless of the injection amount. In comparison with the above, it is possible to reduce disturbance of downflow in a clean room in which the cleaning device is installed, and to reduce contamination due to suction of dust into the cleaning tank.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, and portions corresponding to the above-described conventional example are denoted by the same reference numerals.

In FIG. 1, reference numeral 1 denotes an ice making unit for generating fine frozen particles, 2 denotes a cooling liquid nitrogen supply pipe, 3 denotes a spray nozzle for spraying pure water, and 4 denotes a fine freezing generated in the ice making unit 1. Particles 5 are injection nozzles for injecting the fine frozen particles 4, 6 is a holding arm for holding a semiconductor wafer 7 to be cleaned, 8 is a moving mechanism for moving the semiconductor wafer 7, 9 is a cleaning tank, 10 Is an exhaust duct, 11 is a blower (blower) for exhausting the washing tank, and 12 is a control unit for controlling each part. The above configuration is basically the same as the conventional example.

In the cleaning apparatus of this embodiment, in order to reduce turbulence of down flow in a clean room in which the cleaning apparatus is installed and to reduce contamination due to suction of dust into the cleaning tank 9 as follows. Make up.

That is, the cleaning device of this embodiment includes an inverter 13 for controlling the rotation speed of the exhaust blower 11 and a control unit 12 for performing a series of controls such as control of the injection amount of the injection nozzle 5. By controlling the inverter 13 instead of the control of the conventional auto damper 14, the exhaust amount of the blower 11 is set to an exhaust amount corresponding to the injection amount of the injection nozzle 5. That is, the exhaust amount is set according to the amount of injection of the injection nozzle 5.

Next, the operation of the cleaning apparatus having the above configuration will be described.

Liquid ice is supplied to the ice making section 1 surrounded by the heat insulating material through the liquid nitrogen supply pipe 2 and evaporated therein, thereby cooling the inside of the ice making section 1. After the inside of the ice making section 1 is sufficiently cooled, ultrapure water is sprayed from the spray nozzle 3 to obtain fine frozen particles 4. Fine frozen particles 4 thus obtained
Is injected into the cleaning tank 9 at a high pressure by an ejector method using a gas jet. Thus, the surface of the semiconductor wafer 7 is cleaned by ejecting the fine frozen particles 4 toward the semiconductor wafer 7 held by the holding arm 6.

In this cleaning, the cleaning tank 9 is evacuated by an air blower 11 to prevent the jet flow from being swirled up due to the injection of the fine frozen particles 4. As described above, the control unit 12 controls the inverter 13 to change the exhaust amount to the injection amount of the injection nozzle 5 as shown in the timing chart of the injection amount and the exhaust amount in FIGS. The amount is controlled to correspond to the amount.

That is, in the cleaning apparatus and the exhaust control method of the present invention, as shown in FIG. 2, the exhaust amount of the cleaning tank 9 is controlled to an amount corresponding to the amount of injection from the injection nozzle 5. As compared with the conventional exhaust control shown in FIG. 4, it is possible to reduce the turbulence of the downflow of the clean room in which the cleaning device is installed and to reduce the contamination of the cleaning tank.

[0023]

As described above, according to the present invention, since the exhaust amount of the cleaning tank is controlled to an amount corresponding to the injection amount from the injection nozzle, a constant exhaust amount is obtained regardless of the injection amount. It is possible to reduce the disturbance of the downflow of the clean room in which the cleaning device is installed and to reduce the contamination of the cleaning tank, as compared with the conventional example in which the cleaning apparatus is controlled.

[Brief description of the drawings]

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

FIG. 2 is a timing chart showing a relationship between an injection amount and an exhaust amount in the embodiment of FIG.

FIG. 3 is a schematic configuration diagram of a conventional example.

FIG. 4 is a timing chart showing a relationship between an injection amount and an exhaust amount in a conventional example.

[Explanation of symbols]

 Reference Signs List 4 Fine frozen particles 5 Injection nozzle 7 Semiconductor wafer (object to be cleaned) 9 Cleaning tank 11 Blower 12 Control unit (control means) 13 Inverter

Claims (2)

(57) [Claims] 1. A cleaning apparatus for cleaning an object to be cleaned by injecting fine frozen particles together with a gas at a high pressure from an injection nozzle in a cleaning tank to wash the object to be cleaned. In order to suppress, a blower that exhausts the washing tank, an inverter that controls the rotation speed of the blower, and an inverter that controls the inverter so that the amount of exhaust by the blower depends on the injection amount of an injection nozzle. A cleaning device, comprising: a control unit configured to set a displacement. 2. In a cleaning tank, fine frozen particles are sprayed together with a gas from a spray nozzle at a high pressure onto the object to be cleaned to wash the object to be cleaned. What is claimed is: 1. A method for controlling exhaust air in a cleaning apparatus that exhausts the cleaning tank in order to suppress winding-up, wherein the exhaust amount of the cleaning tank is controlled according to an injection amount of an injection nozzle. A method for controlling exhaust in the device.