JP3213759B2 - Size unit for semiconductor manufacturing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in the field of semiconductor manufacturing to remove fine dust contained in gas.
The present invention relates to a semiconductor manufacturing size unit .

[0002]

2. Description of the Related Art Conventionally, this type of size
As shown in FIG. 4, the tubular ceramic gas filter constituting a part of the filter is formed in a tubular shape in which one of a filter layer 11 made of fine particles and a support layer 12 made of coarse particles is laminated. Both layers are exposed at the end face.

When the ceramic gas filter is modularized and a gas to be filtered is passed from the support layer 12 side to the filtration layer 11 for filtration, the gas to be filtered passes through the filtration layer 11 as shown by an arrow in FIG. Without flowing through the support layer 12 to the secondary side (filtered side) from the end face, and there is a possibility of contaminating the filtered gas on the secondary side. This is because the amount of ventilation increases in proportion to the square of the pore diameter.

Conventionally, in order to cope with such a problem, a size unit for semiconductor production using a tubular ceramic gas filter having sealing portions impregnated with glass at both ends has been known. The ceramic gas filter is manufactured by applying a glass powder to an end and heating and impregnating the powder.

[0005]

However, a semiconductor using the above-mentioned conventional tubular ceramic gas filter is disclosed.
When the manufacturing size unit is used for filtering semiconductor manufacturing gas, when baking (degassing) or during use, substances having a high vapor pressure such as alkali metals and alkaline earth metals, which are glass components, evaporate. Flows to the secondary side and contaminates the filtered gas, which can be a source of contamination for semiconductor products.

Accordingly, an object of the present invention is to provide a semiconductor manufacturing size unit capable of preventing contamination of a secondary side due to inflow of a gas to be filtered and evaporation of a sealant.

In order to solve the above-mentioned problems, a size unit for manufacturing a semiconductor according to the present invention comprises a fine-grained ceramic inside a housing.
Filter layer consisting of a mix and coarse ceramics
A tubular ceramic gas filter laminated with a support layer,
One end is hermetically sealed with a disk with legs, and the other end is circular.
Semiconductor manufacturing size with wheel plates housed in contact
In the unit, the ceramic gas filter
Ceramic powder of the same material as the support layers at both ends
By adhering powder particles into the pores, the filtration layer
That a sealing layer having the same pore size as that of
Features. Here, the equivalent pore size refers to the filtration layer and the sealing layer.
Pore size volume measured with a mercury intrusion porosimeter in the stop layer.
This means that the pore diameter values at which the cloth is maximized are equivalent.

[0008]

In the above means, the air permeability of the sealing layer is equal to the air permeability of the filtration layer by the ceramic powder particles of the same material as the support layer .

[0009] As the ceramic powder particles, alumina, mullite, zirconia, oxide ceramics titania, or silicon carbide, although non-oxide ceramics such as silicon nitride-containing and the like, using the same and a support layer And preferably do not contain alkali metals, alkaline earth metals, heavy metals and the like.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a size unit for manufacturing a semiconductor according to the present invention.
FIG. 5 is a half sectional side view showing one embodiment of a ceramic gas filter constituting a part .

The ceramic gas filter 1 comprises a filter layer 2 made of fine grains of high-purity (99.99%) alumina ceramics and a support layer 3 made of coarse grains of the same ceramics. In the support layers at both ends, the same alumina ceramic powder particles as those of both layers are attached to the support layers at both ends, and the pore diameter of the filtration layer 2 is reduced. 0.13 equivalent to pore size
The sealing layer 4 is provided as μm.

Next, a method for manufacturing the ceramic gas filter 1 will be described. First, 40 parts by weight of alumina powder having a particle size of 0.2 μm and purity of 99.99% and 60 parts by weight of water were crushed and mixed in a ball mill for 24 hours to obtain a high-concentration slurry. The mixture was charged into 75 parts by weight and stirred with a magnetic stirrer to obtain a 10% by weight slurry.

Then, an end of a tubular filter element made of alumina ceramics having a support layer having a pore size of 2 to 3 μm formed on a filtration layer having a pore size of 0.13 μm is immersed in the slurry to form an end pore. After the slurry infiltrated into the portion by capillary action, it was pulled up and dried, and then fired at a temperature of 1200 ° C. to obtain a tubular ceramic gas filter provided with a sealing layer on the support layers at both ends.

The pore size of the sealing layer of the obtained ceramic gas filter was measured by a mercury intrusion porosimeter, and the result was as shown in FIG. From this measurement result, it can be seen that the pore size of the sealing layer is 0.13 μm, which is the same as the pore size of the filtration layer.

[0015] Made tone of the slurry is not limited to the case of using water as the solvent, Metolose solution and PVA solution may be used as a solvent, we are possible to control the length impregnating the filter element by adjusting its viscosity .

The slurry concentration is preferably from 1 to 35% by weight, and if it is less than 1% by weight, the filling rate into the pores becomes low and the efficiency becomes poor. It becomes clogged and does not enter the pores. The formation of the sealing layer can be controlled by the length of dipping in the slurry.

The firing after drying depends on the material,
It is preferable to carry out at a firing temperature for forming the filtration layer or at a firing temperature lower than the firing temperature.

The above-mentioned ceramic gas filter 1 is
As shown in FIG. 3, it is modularized into size units. This size unit is formed in a cylindrical shape from stainless steel or the like, and has a gas inlet 5 at one end (the right end in FIG. 3) and a gas outlet 6 at the other end (the left end in FIG. 3). A ceramic gas filter 1 whose one end is hermetically sealed by a disk with legs 8 made of fluororesin is accommodated in a state in which a circular plate 9 made of stainless steel is in contact with the other end. It is configured.

In the above size unit, the entrance 5
As shown by arrows in the figure, the filtered gas from which the dust has been separated from the support layer 3 of the ceramic gas filter 1 through the filtration layer 2 flows to the secondary side and is discharged from the outlet 6.

[0020]

As described above, according to the present invention, the support
Since aeration rate of the sealing layer by ceramics powder particles of the lifting layer the same material is equal to the aeration amount of the filtration layer with never be filtered gas flows from the support layer directly the secondary side,
The sealing agent does not evaporate during baking or during use as in the past, so that contamination of the secondary side by the gas to be filtered and the sealing agent can be prevented, and consequently contamination of semiconductor products from the ceramic gas filter. Can be eliminated.

[Brief description of the drawings]

FIG. 1 shows a part of a semiconductor manufacturing size unit of the present invention.
It is a half sectional side view showing one example of a constituted ceramic gas filter.

FIG. 2 is an explanatory diagram showing a measurement result of a pore diameter of a sealing layer of the ceramic gas filter.

FIG. 3 is a side sectional view of a size unit using the ceramic gas filter.

FIG. 4 is a side sectional view of an ordinary ceramic gas filter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ceramic gas filter 2 Filtration layer 3 Support layer 4 Sealing layer

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tadayoshi Muto 30 Soya, Hadano-shi, Kanagawa Prefecture, Toshiba Ceramics Co., Ltd. 72) Inventor Akiko Niizuma 30 Soya, Hadano-shi, Kanagawa Toshiba Ceramics Co., Ltd. Central Research Laboratory (56) References JP-A-62-129104 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB Name) B01D 39/20 B01D 39/14 B01D 46/00-46/54

Claims (1)

(57) [Claims] (1) A fine-grained ceramic material is provided in a housing.
Filter layer and a support layer made of coarse ceramics.
Layered tubular ceramic gas filter, one end leg
Hermetically sealed with attached disk, and a circular plate in contact with the other end
Into a size unit for semiconductor manufacturing
In the above, both ends of the ceramic gas filter
Ceramic powder particles of the same material
By adhering in the pores, the same fineness as the filtration layer
Characterized in that a sealing layer having a pore diameter is formed
Size unit for semiconductor manufacturing.