JPH059061Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an in-process type dust removal device used in semiconductor manufacturing equipment, particularly in a CVD process for forming an insulating thin film on a wafer.

Conventional technology In the manufacturing process of semiconductor devices, for example, in the well-known atmospheric pressure CVD process, low pressure CVD process, or plasma CVD process as a means for forming insulating thin films, reaction products such as SiO ₂ of 1 μm or less in semiconductor manufacturing are used. Often, fine powder dust is generated. As an example of semiconductor manufacturing equipment, normal pressure
The CVD device will be explained with reference to Fig. 3.
is a semiconductor wafer placed on a horizontal susceptor 2a, and 3 and 4 are an outer box and an inner box with open bottoms, which are disposed at fixed positions above the endless conveyor belt 2 to which the susceptor 2a is fixed. . A plurality of slit-shaped gas outlets 5a, 5b, . For example, SiH ₄ gas and
O ₂ gas is alternately blown out toward the heated semiconductor wafer 1 located below.

SiH ₄ gas reacts with O ₂ gas "Reaction [SiH ₄ + O ₂ →
SiO ₂ +2H ₂ ] to form a CVD film of SiO ₂ or the like on the semiconductor wafer 1. The reaction products at this time, such as SiO ₂ that were not used for the growth of the CVD film on the semiconductor wafer 1, are partially discharged from the exhaust duct 6 as fine powder of 1 μm or less.
The remainder falls onto the susceptor 2a or adheres to the outer box 3 and inner box 4 and remains in the atmospheric pressure CVD apparatus. If the fine powder dust that remains in the CVD equipment is left unattended, it will contaminate the semiconductor wafers, so the CVD equipment must be stopped after a predetermined operating time, and cleaning, scrubbing, etc. Alternatively, appropriate cleaning treatment such as vacuum suction is performed to remove fine powder dust.

As an example of such a dust removal device, a negative pressure suction type dust removal device is used, in which a motor, a blower, and a filter are built into a vacuum cleaner body, and a flexible air supply duct is connected to the vacuum cleaner body.

By starting the motor of the above-mentioned dust removal device, rotating the blower fan, and suctioning contaminated air at high speed through the air supply duct and filter, fine powder dust attached to the CVD device can be removed. is drawn into the air supply duct together with the air, only the dust is captured by the filter, and the air after the dust has been removed is discharged to the outside from the blower.

Problems that the invention aims to solve: Such fine powder dust is
It is generated not only in the equipment but also in other semiconductor manufacturing equipment such as etching equipment that uses plasma, and as the operating time progresses, reaction residues can be found in various parts of the equipment despite being discharged by the dust removal equipment. As a result, the amount of fine powder dust attached increases. In conventional semiconductor manufacturing equipment, in order to prevent the occurrence of defective products due to the adhesion of fine powder dust, the semiconductor manufacturing equipment is overhauled after a predetermined operating time and dust is deposited in various parts of the equipment. Fine powder dust is regularly discharged, but this method increases the downtime of semiconductor manufacturing equipment, lowers the operating rate of the manufacturing process, and also significantly increases the man-hours required for maintenance management of semiconductor manufacturing equipment. increases to

The main object of the present invention is to provide a semiconductor manufacturing apparatus equipped with an in-process dust removal mechanism suitable for solving the above-mentioned problems observed in conventional semiconductor manufacturing apparatuses.

Means for Solving the Problems In order to achieve the above object, the present invention provides a cleaning device that includes a suction device for air containing fine powder dust and a wet dust removal device that separates and collects the dust from the sucked air. Connect the machine and the exhaust pipe of the dispersion head with a branch pipe with a control valve, and always keep the control valve on the exhaust duct side open and the control valve on the vacuum cleaner side closed, and clean the dispersion head. The present invention provides a semiconductor manufacturing apparatus having an in-process dust removal mechanism that closes an exhaust duct side control valve and opens a vacuum cleaner side control valve.

Function: Selectively open and close two control valves to switch the flow path of fine powder dust formed between the dispersion head and the wet dust removal device.
Dust attached to the dispersion head is removed using an in-process method.

Embodiment FIG. 1 is a perspective view illustrating the overall structure of the device of the present invention, FIG. 2A is a plan view of a vacuum cleaner equipped with a wet dust removal device, and FIG. 2B is a front view thereof. As seen in these drawings, the dispersion head 3 of semiconductor manufacturing equipment, such as atmospheric pressure CVD equipment, is shown.
5 is composed of an outer box 3 and an inner box 4, both of which are open at the lower end and are disposed at a predetermined position above the endless conveyor belt 2 to which susceptors 2a, 2a, . . . for supporting the semiconductor wafer 1 are fixed. An exhaust duct 6 communicating with the space between the outer box 3 and the inner box 4 is connected to the upper part.
Since the operating procedure of this dispersion head 35 is the same as that of the semiconductor manufacturing apparatus shown in FIG. 3, the same components will be designated by the same reference numerals and a description of the overlapping parts will be omitted. The exhaust duct 6 of the dispersion head 35 is a T-shaped branch pipe 37a equipped with control valves 36a and 36b.
and 37b, it is connected to a vacuum cleaner 38 illustrated in FIGS. 2A and 2B, which will be described later. Branch pipe 37a,
Preferably, 37b is constructed from a flexible tube of a heat resistant material, such as stainless steel, to withstand the high temperature exhaust gases that serve as the transport medium for the fine powder dust.

The vacuum cleaner 38 has a wet type dust removing device 39 disposed inside a box-shaped envelope 7, and by attaching casters 8, 8, etc. at multiple locations on the lower surface of the envelope 7, it is possible to clean multiple semiconductors. This forms a shared dust removal device that is moved between manufacturing devices. Reference numeral 10 denotes a ventilure scrubber installed vertically at one end of the envelope 7, and an air supply duct 11 is connected to its upper end. The air supply duct 11 is the envelope 7
It is a flexible pipe extending outward from the pipe, and an air supply port 12 connected to the branch pipe 37a is provided at the tip thereof. Reference numeral 13 denotes a circulation tank connected to the lower part of the ventilium scrubber 10, which is disposed at the bottom of the envelope 7, and has water 14 stored thereinto approximately half way. Reference numeral 15 indicates a circulation pump for circulating water 14 in the circulation tank 13 to the upper part of the ventilium scrubber 10, and reference numeral 16 indicates a circulation pump for circulating the water 14 stored in the circulation tank 13 through a hole 17 provided in the side wall above the water surface. A mist separator connected to the tank 13 removes water droplets in the air flowing in from the holes 17. 18 is an exhaust fan connected to the outlet of the mist separator 16, 19 is a motor that functions as a power source for the exhaust fan 18, and the exhaust fan 18 is fixed on a frame-shaped stand 20 fixed to the bottom of the envelope 7. together with 20
A motor 19 is fixed below. 21 is a rotating shaft of the motor 19, 22 is a pulley coaxially fixed to the rotating shaft 21, and this pulley 22 is connected by a belt 26 to a pulley 25 coaxially fixed to the rotating shaft 24 of a fan 23 of the exhaust fan 18. In this way, the rotational force of the motor 19 is transmitted to the fan 23 of the exhaust fan 18 via the pulley 22, belt 26, and pulley 25. 27 is an exhaust duct extending from the exhaust fan 18 through the envelope 7 to outside the system.

The ventilate scrubber 10 has a small-diameter throat 28 at an approximately intermediate position, and water 1 is passed through a pipe 29 from a circulation pump 15 above the throat 28.
A nozzle 30 is arranged to supply 4 in the form of a spray. The mist separator 16 incorporates a large number of collision plates 31, 31..., and a nozzle 33 is installed at the top of the mist separator 16 to supply water 14a supplied from the outside via piping 32 in the form of a spray. At the bottom of the mist separator 16 is a pipe 3 that sends the falling water to the circulation tank 13.
Connect 4.

Push the envelope 7 to move the cleaner 38 to the connection position with the dispersion head 35 to be cleaned,
After connecting the branch pipe 37a and the intake port 12, the control valve 36a is opened, the motor 19 is started, and the exhaust gas containing fine dust generated in the dispersion head 35 is sucked from the intake duct 11. At this time, the control valve 36b on the side of the branch pipe 37b is closed. Thus intake port 1
2 to the dispersion head 35 with air a.
The fine powder dust b generated is sucked. This air a and dust b are the ventilate scrubber 1.
0, the sprayed water 14 injected from the nozzle 30 is added to this, and while passing through the throat 28 it is accelerated to a speed of about 40 to 50 m/sec, and the water 14 in the circulation tank 13 is be slammed by. As a result, the air a rises to the surface of the water 14 and escapes, while most of the fine powder dust b mixes with the water 14 and settles at the bottom of the circulation tank 13.

The air a coming out of the water 14 is transferred to the water 1 in the circulation tank 13.
The mist separator 16 is sucked into the mist separator 16 through the hole 17 along with some of the scattered particles. While passing between the collision plates 31, 31... of the mist separator 16, moisture in the air a condenses on the collision plates 31, 31...
It drips and is removed as water droplets. In this way, only air a is sent out from the mist separator 16.
This air a is passed through the exhaust fan 18 to the exhaust duct 27.
It is discharged to.

The nozzle 33 of the mist separator 16 is used to wash away dust that adheres to the collision plates 31, 31, . . . with a shower of water 14a due to long-term use.

After cleaning the dispersion head 35, stop the motor 19 and circulation pump 15, close the control valve 36a on the branch pipe 37a side,
Open the control valve 36b on the side of the branch pipe 37b. In this state, the branch pipe 37a and the intake port 12 are separated, and the vacuum cleaner 38 is moved to the next dispersion head (not shown) to be cleaned. The dispersion head 35 that has been cleaned is then returned to its operating state. In addition, control valve 3
A flow control valve 40 is provided in the branch pipe 37b having the dispersion head 6b as a means for adjusting the amount of air discharged from the dispersion head 35 in an operating state.

Although one specific example of the present invention has been described above, the present invention should not be interpreted as being limited by the description of the above embodiment, and many modifications can be included. For example, instead of the portable vacuum cleaner that can be shared between the above-mentioned multiple dispersal heads,
It is also possible to use a portable wet-type dust removal device in which a water tank for collecting dust is disposed below a horizontal air flow path divided into a labyrinth shape by multiple vertically oriented partition plates, or to modify these vacuum cleaners into a fixed type.

Effects of the invention According to the invention, two control valves installed in a branch pipe are selectively opened and closed to remove the fine powder formed between the dispersion head and a vacuum cleaner, that is, a wet dust removal device. By switching the dust flow path at predetermined time intervals, it is possible to remove fine powder dust adhering to the dispersion head in an in-process method using idle time when changing production lots. can. As a result, there is no need to stop the semiconductor manufacturing process for a long time to perform dust removal work, and the overhaul cycle of the semiconductor manufacturing equipment is significantly extended. Thus, the present invention can significantly exceed the level of conventional equipment as a means of improving the operating rate of semiconductor manufacturing equipment and saving labor in removing attached dust.

[Brief explanation of the drawing]

FIG. 1 is a perspective view illustrating the overall structure of the device of the present invention, FIG. 2A is a plan view of a vacuum cleaner equipped with a wet dust removal device, and FIG. 2B is a front view thereof. FIG. 3 is a schematic front view of the dispersion head. 35...Dispersion head, 36a, 3
6b...control valve, 37a, 37b...
... Branch pipe, 38 ... Vacuum cleaner, 39 ... Wet dust removal device.

Claims (1)

[Scope of utility model claims] A suction device for air containing fine powder dust,
A vacuum cleaner equipped with a wet dust removal device that separates and collects the dust from the sucked air and the exhaust pipe of the dispersion head are connected by a branch pipe equipped with a control valve, and the control valve on the exhaust duct side is normally connected. It features an in-process dust removal mechanism that opens the vacuum cleaner side, closes the vacuum cleaner side control valve, closes the exhaust duct side control valve when cleaning the dispersion head, and opens the vacuum cleaner side control valve. Semiconductor manufacturing equipment.