JPH04366338A - Clean ventilation device - Google Patents

Abstract

PURPOSE:To enable a required work to be carried out without any contamination of semiconductor substrate with heavy metal impurities. CONSTITUTION:A clean ventilation device is comprised of a layer 9 filled with lean acid solution 8 for passing air of which dust is removed through a filter 2b at a suction port, and of a filter 7 for removing oxidized heavy metal impurities evaporated in the layer 9.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clean bench used in semiconductor device manufacturing operations.

0002

2. Description of the Related Art Generally, in the manufacturing process of semiconductor devices, there are various operations related to manufacturing, inspecting and assembling semiconductor elements. Since these operations involve handling minute semiconductor devices, they must be performed in a dust-free environment, and the work room and work desk used for the operations must be clean. A work desk called a clean bench was used for this type of work desk.

FIG. 2 is a schematic sectional view of a clean bench showing an example of the conventional technique. Traditionally, this type of clean bench
For example, as shown in FIG. 2, there is a workbench 1, a stand 5 that supports the workbench and to which a filter 2a serving as an air intake is attached, and a duct 4 that is screened from the side of the stand 5 and through which air flows. , and a cover part 6 that covers the workbench 1 and to which a filter 2 for supplying clean air to the workbench 1 is attached. Further, a fan 3 for blowing air was installed between the base portion 5 and the duct 4.

In this clean bench, the fan 3 is always operated during work, and the filters 2a and 2 remove dust (particles) from the air, supplying clean air to the work bench 1.
It was sprayed on top.

[0005]

[Problem to be Solved by the Invention] However, conventional clean benches do not have a means for removing heavy metal impurities in fine particles that pass through a filter, and therefore cannot remove heavy metal impurities from the supplied air. When handling semiconductor substrates in the process of being manufactured in a clean bench, the surface of the semiconductor substrate is often contaminated with heavy metal impurities.
There was a problem of lowering manufacturing yield.

SUMMARY OF THE INVENTION In view of this problem, it is an object of the present invention to provide a clean bench that can be used without being contaminated by heavy metal impurities.

[0007]

[Means for Solving the Problems] The clean bench of the present invention includes a dust removal filter attached to an intake port, a sealed tank for storing an acidic solution through which air passes through the filter, and an acidic solution floating in the sealed tank. It is equipped with a heavy metal impurity removal filter that removes oxidized heavy metal impurities.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a schematic sectional view of a clean bench showing an embodiment of the present invention. As shown in the figure, this clean bench consists of a tank 9 that stores a dilute acidic solution 8 that oxidizes heavy metal impurities with fine particles, and a tank 9 that stores a dilute acidic solution 8 that oxidizes heavy metal impurities with fine particles.
One end side is immersed in the filter 2b, and the other end side is immersed in the filter 2b at the intake port.
and a pipe 1 whose one end is hermetically inserted into the tank 9 and whose other end is connected to the filter 7.
1 was established. Other than that, it is the same as before.

Next, the air supply operation of this clean bench will be explained. First, indoor air is taken in through the air intake port, and dust in the air is removed using the filter 2b. The air from which dirt has been removed is then exposed to a dilute acidic solution via piping 10. At this time, fume-like heavy metal impurities contained in the air are oxidized and become solid. Next, the oxidized solids floating in the tank 9 pass through the pipe 11 and enter the filter 7 where the oxidized solids are completely adsorbed and removed. supply to.

[0011]

Effects of the Invention As explained above, the present invention bubbles air from which dust has been removed by a filter at the intake port in a dilute acidic solution, converts heavy metal impurities in the air into oxidized solids, and evaporates the oxidized solids. By providing a filter for removing substances at a later stage, there is an effect that a clean bench on which work can be performed without being contaminated by heavy metal impurities can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a clean bench showing an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a clean bench showing a conventional example.

[Explanation of symbols]

1 Workbench 2, 2a, 2b, 7 Filter 3 Fan 4 Duct 5 Base part 6 Cover part 8. Dilute acidic solution 9 layers 10,11 Piping

Claims (1)

[Claims] Claim 1: A filter for removing dust that is attached to an intake port, a sealed tank that stores an acidic solution through which air passes through the filter, and a heavy metal impurity removal device that removes oxidized heavy metal impurities floating in the sealed tank. A clean bench characterized by being equipped with a filter for use.