KR20060002232A - Grating panel and clean room system using it - Google Patents

Abstract

The present invention relates to a grating panel such as a floor used in a clean room environment and a clean room system using the same. The grating panel of the present invention includes a base plate having a plurality of perforation holes, wherein the perforation hole has an inlet through which air is introduced and an outlet through which air is discharged, and the inlet is closer to the outlet. Its cross sectional area is reduced and its outlet area increases as it moves away from the inlet.

Description

Grating panel and clean room system using it {GRATING PANEL AND CLEAN ROOM SYSTEM USING THE GRATING PANEL}

1 is a cross-sectional view of a main portion showing a hole formed in a conventional grating panel;

2 is a graph measuring particles for each height in a clean room to which a conventional grating panel is applied;

3 is a schematic view showing a clean room system according to an embodiment of the present invention;

4 is a perspective view of a grating panel installed on the floor of a clean room;

5A is a partially enlarged plan view of a grating panel according to an embodiment of the present invention;

FIG. 5B is a cross-sectional view along the line b-b shown in FIG. 5A; FIG.

6 is a graph comparing the differential pressure in a clean room to which a conventional grating panel is applied and a clean room of the present invention;

7 shows a grating panel having a slotted drill hole;

8 is a graph comparing turbulent kinetic energy (K) in the grating panel of the present invention and the grating panel of the present invention;

9 is a graph measuring particles for each height in a clean room to which a conventional grating panel is applied and a clean room of the present invention;

10 is a cross sectional view of a main portion of a grating panel having perforations of different shapes;

11 is a cross sectional view of a main portion of a grating panel having perforations of different shapes.

* Explanation of symbols for main parts of the drawing

100: clean room system

110: clean room

120: fan filter unit

130: grating panel

132: base plate

134: drilled hole

136: inlet

138: outlet

140: middle part

The present invention relates to grating panels such as floors used in clean room environments, and clean room systems using the same.

Semiconductor devices and LCDs are very precise devices, and are manufactured in a manufacturing environment with a high degree of cleanliness, unlike general product manufacturing. Many facilities of semiconductor devices operate separate clean rooms to form and maintain such a high degree of cleanliness.

Workers in clean rooms wear special dustproof clothing to minimize the generation of foreign substances such as dust. In addition, air (clean air) is discharged at a pressure slightly higher than atmospheric pressure in the upper part of the clean room space, and a grating panel, which is a flooring material having holes, is installed at the bottom to release air. Thus, air flows vertically in the clean room space. Therefore, contaminants in the cleanroom space collect towards the floor and they are discharged through the holes in the grating panel.

However, molecular contaminants in the clean room atmosphere, which are collectively referred to as Nano Partical and Airborne Molecular Contamination (AMC), are not easily removed due to their non-visual characteristics unlike micro particles. For the rapid removal of nanoparticles and AMC, the differential pressure and wind speed conditions must be set to 18% higher than the conditions for removing microparticles, which leads to an increase in operating costs of the air conditioning system, which leads to an increase in manufacturing cost.

Also, as shown in FIG. 1, vortices are generated in the process of passing air through holes formed perpendicular to the grating panel. Vortex is most likely to occur at the part indicated by the dotted line (the inlet edge of the hole and the outlet edge of the hole).

Figure 2 shows the particle measurement results for each height of the clean room, after generating the particles (30,000 ~ 35,000 counter / cf) at a height of 0.2m in the grating panel, the particles by height was measured. As a result of the measurement, it can be seen that particles are distributed up to 70 cm in height by vortex.

As such, the vortices generated around the holes in the grating panel not only hinder the rapid evacuation of the air, but also cause serious contaminants (especially; nanoparticles and AMC) to rise to 70 cm above the grating panel (bottom) to contaminate the surroundings. Cause problems.

It is therefore an object of the present invention to provide a new type of grating panel in which air is smoothly vented and a clean room system using the same. It is another object of the present invention to provide a new type of grating panel and a clean room system using the same, which can minimize the vortex and prevent the rise of contaminants.

According to a feature of the present invention for achieving the above object, a grating panel such as a floor used in a clean room environment includes a base plate having a plurality of perforation holes that are passages through which air in the clean room is exhausted to the outside. .

According to this embodiment, the perforation hole has an inlet through which air flows in and an outlet through which air flows out, and the closer to the outlet, the cross-sectional area thereof decreases, and the outlet is farther from the inlet. As it increases, its cross-sectional area increases.

According to this embodiment, the inlet and the outlet are inclined or curved.

According to this embodiment, the perforation holes are round or slots.

According to the present embodiment, the middle portion may further include the same middle portion between the inflow portion and the outlet portion.

According to this embodiment, a tile made of vinyl chloride resin may be attached to the upper surface of the base plate.

According to another aspect of the present invention for achieving the above object, the clean room system comprises a clean room; An air supply unit installed in the ceiling of the clean room and supplying clean air into the clean room; An air exhaust portion spaced from the bottom of the clean room and having a grating panel having a plurality of perforation holes through which air in the clean room is exhausted to the outside; The perforation hole decreases in cross-sectional area as it goes down, and then increases in cross-sectional area.

According to the present embodiment, the drilling hole has an inlet through which air flows in and an outlet through which air flows out; The closer the inlet is to the outlet, the cross-sectional area decreases, and the outlet portion increases its cross-sectional area as it moves away from the inlet.

For example, embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Accordingly, the shape of the elements in the drawings and the like are exaggerated to emphasize a clearer description.

Hereinafter, an embodiment of the present invention will be described in more detail with reference to FIGS. 3 to 11. In the drawings, the same reference numerals are given to components that perform the same function.

3 is a schematic diagram illustrating a clean room system according to an exemplary embodiment of the present invention. 4 shows a grating panel installed on the floor of a clean room.

Referring to FIG. 3, the clean room system 100 includes a clean room, an air supply unit, and an air exhaust unit. The air supply unit includes a fan filter unit 120 installed on the ceiling of the clean room 110. The fan filter unit 120 is a unit in which a filter and an air supply fan are modularized into one unit, and filter the circulating air to supply the inside of the clean room. Although not shown, a ceiling filter such as a HEPA (High Efficiency Particulate Air) filter or ULPA (Ultra Low Penetraticn Air) filter may be installed on the ceiling of the clean room to remove foreign substances such as dust of several microns.

Air passes through the fan filter unit 120 and is supplied into the clean room 110 to form vertical airflow. The vertical airflow of the air sinks the contaminants generated in the clean room 110 to the floor to block the contaminants from reaching the height at which the process is performed. In addition, these contaminants are discharged and removed together with the air through the grating 130 panel of the air exhaust to maintain high cleanliness in the clean room.

The air discharged through the grating 130 panel is moved back to the ceiling by the fan filter unit 120 and recycled through the fan filter unit 120 to maintain high cleanliness in the clean room.

Looking at the grating panel 130 in more detail as follows.

3 and 4, the grating panel 130 is installed to allow air to flow between the interior of the clean room 110 and the subfloor 112. The grating panel 130 is supported by the support structure 114 from a subfioor 112.

The grating panel 130 includes a base plate 132 made of steel, stainless steel, or aluminum. Of course, other materials such as composites may also be used in addition to these materials. The grating panel 130 may be attached to the support structure 114 by a fastener or may simply be placed on the structure 114. In either case, the grating panel 130 is attached to a wiring, ductwork or other infrastructure element 116 that lies in the area 115 between the grating panel and the bottom bottom 112. It can be easily removed for access.

On the upper surface of the base plate 132 of the grating panel 130, a tile 133 made of vinyl chloride resin is attached to provide a protective wear surface.

For example, the grating panel 130 may be treated to provide any number of desired surface properties. For decorative and functional purposes, for example, for acoustic attenuation, conductivity control and other desired functions, the surface of the grating panel is covered with carpet tiles or other suitable floor treatments. In addition, the grating panel 130 may be coated or plated with epoxy to provide desirable properties such as static control, wear resistance, protection from chemical spills, and the like. Of course, the grating panel can be used as it is without any treatment.

Referring again to FIG. 4, the size of the grating panel 130 is typically 600 mm * 600 mm, but in some applications other sizes of panels may be used, such as 750 mm * 750 mm and 500 mm * 500 mm. These panels can be molded easily. In order to match the selected support structure 114 and the grating panel 130, the dimensions may be selected as desired.

The grating panel 130 is perforated with a plurality of holes 134, which are passages through which air in the clean room is exhausted to the outside (bottom space). The perforated hole 134 pattern of the present invention provides a pattern that is attractive in appearance and facilitates substantial air flow through the panel. When using a hole of the size shown, an air flow area of about 18% is provided.

5A is a partially enlarged plan view of a grating panel according to an embodiment of the present invention, and FIG. 5B is a cross-sectional view taken along the line b-b shown in FIG. 5A. 5A and 5B, the drilling hole 134 has an inlet 136 through which air is introduced and an outlet 138 through which air is discharged. The inlet 136 is inclined to decrease its cross-sectional area closer to the outlet 138, and the outlet 138 is inclined to increase its cross-sectional area as it moves away from the inlet 136. The narrowest portion L2 of the drilled hole 134 is about 8.5 mm in diameter (same diameter as the existing drilled hole), and the widest portion L1 of the drilled hole is about 10 mm in diameter. For example, the drilling hole 134 may be made of a slit type as shown in FIG.

The flow of air through the perforation hole 134 is shown in dashed lines in FIG. 5. As shown in FIG. 5, the punching hole 134 is inclined to form an inlet 136 which is an inlet through which air is introduced, thereby alleviating a collision angle with air flowing in the vertical direction. Air impinging on the inclined surface 136a of the inlet 136 is naturally guided toward the outlet 138 along the inclined surface, so that smooth air flow is generated at the inlet 136 of the drilling hole. In addition, the outlet portion 138, which becomes an outlet through which air escapes, is gradually widened, so that air entering the outlet portion 138 from the inlet portion 136 is discharged more quickly.

6 is a graph comparing the differential pressure in the clean room Q1 to which the existing grating panel is applied and the clean room Q2 of the present invention. As shown in Figure 6, the internal pressure of the clean room (Q2) of the present invention can be seen that the pressure drop (pressure drop) reducing effect of 2.379 Pa or more than the internal pressure of the existing clean room (Q1) occurred (42% improvement effect). This reduces turbulence and pressure loss due to the nozzle effect.

As a result, vortex phenomena, which were frequently generated at the inlet and outlet edge portions of the punched hole 134, are reduced, thereby enabling the rapid removal of contaminants (particularly, nanoparticles and AMC). In addition, it is possible to reduce the critical height rise of the pollutant caused by the turbulence phenomenon. FIG. 8 illustrates the turbulent kinetic energy (K1) of the existing grating panel and the turbulent conversion coefficient (K2) of the grating panel of the present invention. As shown in FIG. 8, the grating panel of the present invention is shown. The turbulence conversion factor is reduced by 37% compared to the existing grating panel around the perforation hole, and the differential pressure and mass flow are increased due to the reduced turbulent flow.

9 generated particles 30,000-35,000 counter / cf at a height of 0.2 m apart from the grating panel, and then measured particles by height. At this time, the wind speed of the fan filter unit 120 is 0.4 m / s. As a result of measuring the particle critical height, the grating panel of the present invention can be seen that the particle critical height is reduced by 40 cm compared to the conventional grating panel (prior art).

10 shows a grating panel 130a having drill holes 134a of different shapes. The grating panel 130a has perforation holes 134a having an inlet 136, an outlet 138 and a middle portion 140 formed therebetween. The perforation hole 134a has the same structure and function as the inlet part 136 and the outflow part 138 as the above-described perforation hole 134, and the middle part 140 is formed in the same straight cross-sectional shape. There are structural features to building. The air flow in the drilled holes having this structure is made similar to the air flow in the drilled holes 134 described above.

11 shows a grating panel 130b having yet another shape of perforation holes 134b. The material and structure of this embodiment are essentially the same as the grating panel 130 described above, except that the shape of the perforation hole is formed to be curved.

As shown in FIG. 11, the drilling hole 134b has an inlet 136b through which air flows in and an outlet 138b through which air flows out. The inlet 136b is curved to decrease its cross-sectional area as it approaches the outlet 138b, and the outlet 138b is curved to increase its cross-sectional area as it moves away from the inlet 136b. In these curved perforations, the air flow (indicated by the dotted lines) is as smooth as the air flow in the perforations 134 described above.

In the above, the configuration and operation of the grating panel according to the present invention and the clean room system using the same are illustrated according to the above description and the drawings, which are merely examples and various changes without departing from the technical spirit of the present invention. And of course, it is possible to change.

Application of the present invention reduces the turbulence and pressure drop loss due to the reduction of the turbulent kinetic energy, thereby increasing the air flow rate per unit time. As a result, it is possible to lower the particle generation threshold height by 40 cm due to the generation of particle control effect compared to the grating panel having a vertical type of perforation hole, thereby maximizing nano particle and AMC (Airbone Molecular Contamination) control effect.

Claims (17)

For grating panels such as floors used in clean room environments: A base plate having a plurality of perforation holes, which are passages through which air in the clean room is exhausted to the outside; The perforation hole It has an inlet through which air flows in and an outlet through which air flows out, And the cross-sectional area of the inlet portion decreases closer to the outlet, and the cross-sectional area of the outlet portion increases the further away from the inlet. The method of claim 1, Grating panel, characterized in that the inlet and the outlet is inclined. The method of claim 1, And a grating panel, wherein the inlet and the outlet are curved. The method of claim 1, Grating panel, characterized in that the hole is circular. The method of claim 1, Grating panel, wherein the perforation hole is a slot. The method of claim 1, And a middle portion having the same cross-sectional area between the inlet and the outlet. The method of claim 1, A grating panel, characterized in that a tile made of vinyl chloride resin is attached to the upper surface of the base plate. The method of claim 1, And said apertures provide an air flow area of about 18%. The method of claim 1, Grating panel, characterized in that the widest portion of the perforated hole is about 10mm in diameter, the narrow portion is about 8.5mm in diameter. In a clean room system: Clean room; An air supply unit installed in the ceiling of the clean room and supplying clean air into the clean room; An air exhaust portion spaced from the bottom of the clean room and having a grating panel having a plurality of perforation holes through which air in the clean room is exhausted to the outside; And the cross-sectional area is increased again after the perforation hole decreases downwards. The method of claim 10, The drilling hole has an inlet through which air flows in and an outlet through which air flows out; The cross-sectional area of the inlet is reduced closer to the outlet, the cross-sectional area is increased as the outlet is farther from the inlet. The method of claim 11, And the inlet and the outlet are inclined. The method of claim 11, And the inlet and the outlet are curved. The method of claim 11, And a middle portion having the same cross-sectional area between the inlet and the outlet. The method of claim 10, The clean hole is circular. The method of claim 10, The clean hole is a slot. The method of claim 10, The grating panel further comprises a tile made of vinyl chloride resin on the upper surface.

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