JPS6121472A - Valve for vacuum and high pressure application - Google Patents

Abstract

PURPOSE:To prevent gas before valve selection from mixing in that after being selected, by forming the inside of a wall surface to be connected by a valve into the same plane surface or the same curvature and a projection part at a time when a takeout port or an intake port of the gas is closed. CONSTITUTION:A valve is made up of installing two gas intake ports 11 and 12, a bellows 13, a driving shaft 14, a stem 17, a connection wall surface 19, an air cylinder 21, a gas takeout port 23, etc. And, opening or closing of this valve is carried out by the air cylinder 21 in a way of contacting or separating the step 17 to or from the gas takeout port 23 via the driving shaft 14. At this time, an outer wall of the connection wall surface 19 is set down to a hitting surface of the stem 17, and the stem 17 is formed in conformity with a form of this hitting surface. According to this method, when selection of a gas flow takes place, capacity at the valve rear stream side is sufficiently filled up with a gap between the stem 17 and the connection wall surface 19 whereby the clearance can be brought to zero in substance. Therefore, gas before valve selection is preventable from mixing in that after being selected.

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICATION J The present invention relates to the rapid switching of gas flows, such as those requiring normal pressure or vacuum and high pressure.

4. Prior Art FIG. 5 shows an example of a conventional vacuum or high-pressure valve connection mode.

In the function shown and depicted in this figure, valves (53) and (54) are opened alternately, thereby causing valves (51) and (5
It has the function of selecting the gas that flows through the pipe shown in (2) and introducing the gas into the pipe shown in (55). The arrow in the figure indicates the direction of gas flow, and
In Figure (a), the valve (54) is closed and the valve (53) is open. Also the fifth
In Figure (b), the valve (53) is closed and the valve (54) is open.

In Fig. 5, when trying to switch the gas flow from state (a) to state (b), the gas before switching remains in the shaded area in Fig. (b), and from state (b) to state (b). If you try to switch the gas flow to state a), the gas from before switching will remain in the shaded area in the diagram (a). Due to the closed state, it is generally necessary to perform evacuation or replacement with inert gas from the piping (55) side.

"Problem to be Solved by the Invention" This has caused a long switching time for the gas flow from the (a) state to the (b) state and from the (b) state to the (a) state. The present invention relates to a vacuum and high-pressure gas valve structure which eliminates the need for operations such as evacuation or gas replacement when switching gases, and which aims to quickly switch gas flows without mixing.

"Means for solving the problem" As shown in Figure 5, when switching gases using a combination of conventional gas valves, the volume of the shaded area in Figure 5 cannot be ignored, and the residual gas A mixture of was occurring. The inventors of the present invention have made earnest efforts to solve this problem. A feature of the present invention is that by improving the shape of the gas valve, the shaded area in FIG. 5 can be ignored.

FIG. 1 shows a cross-sectional view of an example of the shape of a vacuum and high-pressure valve according to the present invention. FIG. 1(a) shows the valve in the closed state, and FIG. 1(b) shows the valve in the open state.

The valve includes gas intake ports (11) and (12), a bellows (13), a motion introduction shaft (14), a bellows support (15), a support for the motion introduction shaft (16), and a stem (
17), temple ring (18).

- Connection wall (19), valve wall (19), air cylinder (21).

Air cylinder support (22), gas outlet (23)
). The opening and closing of the valve is performed by controlling the pressure on the air cylinder. As can be seen from this figure, the outer wall of the connecting wall surface (19) is a contact surface for the stem (17), and the shape of the stem (17) matches the shape of this surface. In this example, the tip of the valve wall (20) is connected to the outer wall of the connection wall (19) by welding, but the connection may also be made by screwing or reheating as long as the gas is sufficiently sealed. It is possible. By using an active body such as a step motor instead of the air cylinder (21), the stem (17) can be set to move continuously, minimizing the conductance of the valve to the gas flow (in this example In this case, you can set it variably from O) to the maximum.

The diagonally shaded portion of the stem (17) filling the gas outlet (2) may protrude from inside the connecting wall surface (19) at the outlet.

``Operation'' If a valve as illustrated in FIG. 1 is used to select and switch the gas flow as illustrated in FIG. 5, a structure as illustrated in FIG. 2 can be considered. With the structure shown in FIG. 2, the volume of the hatched portion in FIG. 5 can be made substantially zero by sufficiently filling the gap between the stem (17) and the connecting wall surface (19). This made it possible to prevent the gas before switching from mixing with the gas after switching, which could not be avoided with the conventional method shown in FIG. The number of gas valves is not limited to two, but as long as the spatial arrangement allows, when using three or more gas valves, have three or more gas outlet ports (two ports) and switch between them without mixing gas with each other. It is also possible to configure the system so that it can be performed continuously.

Embodiment FIGS. 3(a) and 3(b) show an embodiment in which a gas valve according to the present invention is used in a gas introduction section of a semiconductor manufacturing device. Furthermore, Fig. 3(c) shows an example in which a gas switching section configured using a conventional valve is used in a gas introduction section of semiconductor manufacturing equipment.
Shown below.

Among these, FIG. 3(a) shows three valves according to the present invention.
This prevents residual gas from entering when switching gases. Figure 3(b) shows (31), (32), (3
3) shows an example in which the gas introduced in step 3) is directly introduced into the reactor (35) without going through the common pipe (34).

That is, gas valves as illustrated in FIG. 1 are directly constructed at three locations on the wall surface of the reactor. The wall surface of the reactor (35) is the connecting wall surface (19) in FIG.

An amorphous silicon PIN junction diode was manufactured using the gas inlets shown in FIG. 3 and the same plasma CVD semiconductor manufacturing apparatus. Examples will be shown and explained below.

Comparative Example 1 A diode was manufactured using the gas introduction part shown in FIG. 3(c). During production, each layer of P, I, and N was formed through evacuation in order to avoid mixing of gas in the piping. The manufacturing conditions for the P, I, and N type amorphous silicon layers were exactly the same except that different gases were used. Vacuuming was performed for 1 hour each. A graph of the I-■ characteristics of the diode produced by this method is shown in (d) of FIG.

Example 1 A diode was manufactured using the gas introduction part shown in FIG. 3(a). During fabrication, the P, T, and N layers were formed only by switching gases, and no evacuation was performed. In addition, the operation of semiconductor manufacturing equipment is P, I, N
The conditions were set as amorphous silicon for each layer of the mold.

A graph of the IV characteristics of the fabricated diode is shown in (a) in FIG.

Example 2 The I/-V characteristics curve of a diode manufactured in exactly the same manner as in Example 1 except that the gas introduction part shown in FIG. 3(b) was used is shown in FIG. 4(b). Shown below.

Example 3 FIG. 4(c) shows an IV curve of a diode manufactured in exactly the same manner as in Example 1 except that the gas introduction part shown in FIG. 3(c) was used.

"Effects of the Invention" From the four graphs shown in FIG. Characteristics of diode fabricated by vacuuming (
This is the same as d), and it is clear that the time required for evacuation is reduced in the manufacturing process. In addition, the characteristics (c) of a diode manufactured using a conventional gas introduction part without evacuation are as shown in (a) due to the effect of residual gas.
It is inferior to both the characteristics shown in (b) and (d).

It is clear that the valve structure according to the present invention is effective in speeding up gas switching.

[Brief explanation of the drawing]

FIG. 1 is an example of a cross-sectional view of a vacuum and high-pressure valve according to the present invention, including a gas intake (IIL (12)), a bellows (
13), motion introduction shaft (14), bellows support (15L
Movement introduction shaft support (16), stem (17), ○
Ring (18), connection wall (19), valve wall (
20), an air cylinder (21), an air cylinder support (22), and a gas intake port (23). FIG. 2 is an example of an apparatus for switching gas flows using vacuum and high-pressure valves according to the present invention. FIG. 3 shows a semiconductor manufacturing apparatus t (a), (b) having a gas introduction section using the high pressure and vacuum valve of the present invention, and a semiconductor manufacturing apparatus (c) having a conventional gas introduction section. (31)
. (32) and (33) are gas inlet ports, and (35) is a semiconductor manufacturing device including a reactor. (36), (37)
, (38) is a vacuum and high pressure valve according to the present invention. FIG. 4 shows the characteristics of an amorphous silicon diode having a PIN junction manufactured using the semiconductor manufacturing apparatus shown in FIG.乍65 Figure 11 record Kasu = 7i, t714 moxibustion.

Claims (1)

[Claims] 1. In a valve that controls opening and closing of a gas flow, when the gas outlet or the gas intake, or both, are in a closed state, the valve is flush with or flush with the inside of the wall surface to which the valve is connected. Vacuum and high pressure valves characterized by forming a curved surface or having a protrusion. 2. A patent claim characterized in that the conductance for the gas flow can have any combination of continuous values, maximum and minimum values, and intermediate values thereof. Vacuum and high pressure valves listed in item 1. 3. The vacuum and high pressure valve according to claim 1, characterized in that it has a combination of one to two or more gas inlets or outlets.