Fluid handling – Systems – With flow control means for branched passages
Reexamination Certificate
2000-04-24
2001-04-17
Fox, John (Department: 3753)
Fluid handling
Systems
With flow control means for branched passages
C137S613000
Reexamination Certificate
active
06216739
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a gas control device integrated on a panel and provided in a high purity gas supply system for manufacturing a semiconductor device, so that the gas is cleaned and the supply thereof is controlled.
A conventional gas control device provided in the high purity gas supply system for manufacturing a semiconductor device comprises a plurality of independent gas control units connected by joints and pipelines, thereby to form a gas control line. The gas lines are disposed in parallel on a base plate so as to be integrated on a panel.
However, when a number of independent gas control units are connected by the pipelines and joints, the gas line becomes long and the inner capacity of the gas control device within the semiconductor manufacturing system becomes large. In addition, since each gas line has different passage structure, the gas control unit cannot be easily attached or detached. Hence the total manufacturing lead time for designing, producing and assembling the manufacturing system is increased. As a result, the initial rise time at the time of installment of the system becomes longer, and the manufacturing processes become complicated and therefore expensive. In addition, since it is difficult to replace the gas control units, the conventional device cannot deal with a situation where the flow passages must be changed.
Regarding the performance of the gas control device, there are generated welding fumes and particles which deteriorate the welded parts and hence shorten the life of the pipeline. With regard to the cost, the yield of the products is low and the cost for maintenance is high. In addition, since the gas control device cannot be reduced in size, when integrating the device on the panel, there occurs cases where the gas lines are disposed in upper and lower surfaces of the panel or in multiple layers.
In order to connect the gas control units in the gas line to a passage block, there has generally been employed the use of a flange or bolts. However, such a connecting method causes unbalance in tightening force of each bolt, thereby decreasing reliability, and moreover, the assemblage man-hour is increased, so that the cost rises.
In order to resolve these problems, the applicant of the present invention has proposed in Japanese Patent Application Laid Open 10-300000, a structure for integrating the gas control units on a panel wherein the gas control units are mounted on a base plate and connected to each other by a plurality of gas passage blocks. Such a structure will be schematically described with reference to FIG.
10
.
Referring to
FIG. 10
, a passage block
101
has a gas inlet passage
102
and a gas outlet passage
103
formed therein. Peripheral sealing beads
104
and
105
are formed at the openings of the passages
102
and
103
. An annular metal gasket
106
is disposed between the sealing bead
104
of the passage block
101
and the sealing bead
105
of the adjacent passage block
101
. An external thread
107
is formed on each passage block
101
on the outer periphery thereof adjacent one end portion, and a nut
108
is engaged with the thread
107
. A union nut
109
mounted on the nut
108
engages an external thread
110
formed on the outer periphery of the adjoining passage block
101
at the end portion thereof. Thus the adjacent passage blocks
101
are hermetically detachably connected to each other while communicating the gas outlet passage
103
of one block with the gas inlet passage
102
of the other block. The connected passage blocks
101
, only two of which are shown in
FIG. 10
, are detachably mounted on a base plate
111
.
Desired gas control units such as manual diaphragm valve
112
having a toggle joint and a filter unit
113
are mounted on the passage blocks
101
. The diaphragm valve
112
and the filter unit
113
each has a connecting member
114
which is inserted in an upper opening
115
formed in each passage block
101
interposing a metal gasket
116
. Thus a gas inlet passage
117
formed in the connecting member
114
is communicated with the gas inlet passage
102
and a gas outlet passage
118
formed in the connecting portion
114
is communicated with the gas outlet passage
103
through the gasket
116
. A union nut
119
disposed on the outer periphery of the connecting member
114
is screwed on an external thread
120
formed on the outer periphery of an upper portion of the passage block
101
. Thus the connecting member
114
is hermetically detachably mounted on the passage block
101
. Besides the manual diaphragm valve
112
and filter unit
113
, other gas control units such as an automatic diaphragm valve, mass flow controller, regulator, automatic diaphragm valve having a check valve may be selectively used.
The above-described conventional integrated gas control device is advantageous in that while the passage blocks
101
are horizontally connected to one another by way of the end portions thereof, the gas control units
112
and
113
are vertically disposed and connected to the passage blocks
101
. Accordingly the gas passage structure and gas lines can be linearly disposed and the size thereof reduced, resulting in decrease in the overall size of the device.
Since the gas line can be constructed utilizing standardized parts, the passage can be largely arbitrarily constructed. Accordingly not only the total manufacturing lead time for designing, producing and assembling the manufacturing device and the initial rise time are decreased, but the arrangement of the passages can be changed with more ease when required. In addition, since the pipeline need not be welded for connecting the passage blocks
101
, the fumes can be prevented from generating, so that it is possible to elongate the life of the device and to improve the yield of the products. Moreover, the gas control units
112
and
113
can be easily detached from the passage blocks
101
by simply removing the union nuts
119
on the connecting members
114
, and hence easily replaced. Therefore, the maintenance of the device is simplified and the cost thereof decreased.
The union nut
119
is used in order to attach the control unit
112
or
113
to the passage block
101
, so that the entire control unit can be fastened with a well-balanced force without applying couple of forces thereto. Hence a tight seal can be maintained, thereby improving reliability.
In the conventional integrated gas control device, since the adjacent passage blocks are connected to each other by way of screws, it is necessary to interpose the metal gasket
106
between the sealing beads
104
and
105
at the end portions of the passage blocks
101
so that the seal may be ensured. However, since the number of sealing portions is increased, there is a possibility of deteriorating the overall sealing effect. In order to prevent such a problem from occurring, the metal gasket
106
and sealing beads
104
and
105
must be accurately machined. Moreover, the threads
107
and
110
must be formed on the outer periphery of the passage block
101
and the nut
108
and the union
109
must be provided, resulting in the increase in machining portions and the number of parts. Accordingly, the lead time for the manufacturing the device is increased, and the manufacturing process becomes complicated so that the cost is increased. Furthermore, since a space for moving the union nut
109
engaged with the thread
110
is necessary, a sufficient space is still required between each of the gas control units
112
and
113
mounted on the passage blocks
101
, thereby rendering it impossible to sufficiently shorten the gas line.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an integrated gas control device wherein standardized parts are used to enable the manufacturing lead time to be decreased, distances between the gas control units to be shortened by attaching the passage blocks on a base without directly connecting the block with other blocks, and the number of machining
Fukushima Yoshitomo
Sato Kazuhisa
Benkan Corporation
Birch & Stewart Kolasch & Birch, LLP
Fox John
LandOfFree
Integrated gas control device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Integrated gas control device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Integrated gas control device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2484481