JPH0499264A - Vacuum device - Google Patents

Abstract

PURPOSE:To increase the working rate of a vacuum device provided with an air lock mechanism by moving the mechanism part into a first vacuum chamber and substantially decreasing the surface area of a second vacuum chamber affecting the first vacuum chamber to reduce the inflow of gas to the first vacuum chamber. CONSTITUTION:A plate-shaped lid 13 is provided to the moving part 12 holding the mechanism part 3 and traveled, and a sealing frame 14 furnished with a sealing material 15 is provided to a second vacuum chamber 7 close to a gate valve 8. The mechanism part 3 is transferred into the first vacuum chamber 2 and positioned, and the lid 13 is pressed on the frame 14 through the sealing material 15 to block vacuum. Accordingly, since the influence of the gas adsorbed in the vacuum chamber 7 is minimized, the mechanism part 3 is transferred to the vacuum chamber 7, the pressure is returned to atmospheric pressure, then the chamber is again evacuated, however, the time required for the process is made shorter than before, and the working rate of the vacuum device is increased.

Description

[Detailed Description of the Invention] [Summary] Regarding a vacuum device that is continuously used in an ultra-high vacuum, the purpose of improving the operating rate of the device is to provide a first vacuum chamber having an ultra-high vacuum evacuation system; In a vacuum apparatus with an air mechanism, a second vacuum chamber including a movable mechanism within the first vacuum chamber and having a rough exhaust system is provided adjacent to the first vacuum chamber via a gate valve. A lid part for shielding the first vacuum chamber and the second vacuum chamber is provided on the movable part that moves with the gate valve, and a sealing frame is provided on the inner wall of the vacuum chamber near the gate valve. The vacuum device is characterized in that when the mechanism section is moved to the first vacuum chamber and positioned, the lid section and the sealing frame are in close contact with each other via a sealing material to shield the vacuum chamber.

[Industrial application field]

TECHNICAL FIELD The present invention relates to a configuration of a vacuum device, particularly an ultra-high vacuum device, with improved operating efficiency.

Ultra-high vacuum devices are used in devices for forming thin film materials, such as molecular beam crystal growth devices, and materials evaluation devices, such as electron beam diffraction devices and Auger electron spectroscopy devices.

Some of these devices are used in the mass production of semiconductor devices.

For example, molecular beam crystal growth equipment is used for epitaxial growth of laser diodes, high electron mobility transistors, and the like.

Therefore, it is required to increase the operating rate of these devices.

[Conventional technology]

These ultra-high vacuum devices have various mechanical parts attached to a vacuum chamber.

For example, in a molecular beam crystal growth apparatus, a molecular beam source cell that generates a molecular beam and a substrate manipulator that rotates and heats a substrate that performs crystal growth are attached.

As the molecular beam source cell performs crystal growth, the source (evaporated material) in the cell decreases, and it becomes necessary to replenish the source.

Further, the substrate manipulator may sometimes fail.

In such cases, the inside of the device is returned to the atmosphere from ultra-high vacuum to replenish the source and perform repairs.

As described above, in ultra-high vacuum devices, the inside of the device is often returned to the atmosphere.

By the way, when the apparatus is returned to the atmosphere in this way, moisture (H2O) and oxygen (02) are present on the inner wall surface of the vacuum chamber.

Adsorption of atmospheric gas components such as nitrogen (N2) and carbon dioxide (CO2) occurs.

Therefore, after the inside of the vacuum device is completely returned to the atmosphere, i::1
Return to ultra-high vacuum of about 0-” to 10-” Torr t+:
, it is necessary to bake the device at about 200° C. and evacuate it for about a week.

For this reason, in order to improve the operating rate, a vacuum device with an air lock mechanism as shown in FIG. 3 has been put into practical use.

That is, as shown in FIG. 3(A), in a vacuum apparatus, there is a first vacuum chamber 2 having an ultra-high vacuum evacuation system 1, and a molecular beam source cell, etc. that can be moved into the first vacuum chamber 2. Mechanism part 3
A second vacuum chamber 7 is provided with a crude exhaust system 6 consisting of, for example, a Turho molecular pump 4 and an oil rotary pump 5.
are arranged adjacent to each other with a gate valve 8 interposed therebetween.

Further, a gate valve 9 is also provided between the rough exhaust system 6 and the second vacuum chamber 7.

In operation, first, when the device is used normally, the gate valve 9 is closed and the ultra-high vacuum pumping system I, which consists of an ion pump, for example, is opened.
to move the first vacuum chamber 2 from lo-9 to lO-" To
It is maintained at an ultra-high vacuum of about rr.

In this case, as shown in the same figure (B), the mechanism section 3 is moved to the first vacuum chamber 2 by a moving mechanism 11 equipped with a heros 10, and operations such as molecular beam generation are performed. ing.

Next, if it becomes necessary to expose the mechanism section 3 to the atmosphere for source replenishment, etc., leave the ultra-high vacuum evacuation system 1 in operation 5.
After moving the mechanical section 3 to the second vacuum chamber 7 by the moving mechanism 11 and closing the gate valve 8, the second vacuum chamber 7 is returned to the atmosphere.

To return the mechanism section 3 to the first vacuum chamber 2, open the gate valve 9, operate the rough exhaust system 6 to evacuate the second vacuum chamber 7, and then close the gate valve 9. , the gate valve 8 is opened and the mechanism section 3 is moved to the first vacuum chamber 2 by the moving mechanism II.

In this way, a state is reached in which the mechanism section 3 can perform operations such as molecular beam generation again.

However, in such a vacuum device with an air lock mechanism, gas components in the atmosphere are adsorbed on the inner wall of the second vacuum chamber 7 when the second vacuum chamber 7 is returned to the atmosphere.
If the gate valve 8 is opened without sufficient exhaust, the second
The gas adsorbed on the inner wall of the vacuum chamber 7 is released and enters the first vacuum chamber 2, increasing the pressure in the first vacuum chamber 2.

Therefore, it is necessary to open the gate valve 8 after sufficiently removing the adsorbed gas in the second vacuum chamber 7. For this purpose, the second vacuum chamber 7 is baked at a temperature of about 200°C for half a day to one day. Exhaust for at least lo-8~1O-9T
It is necessary to obtain a vacuum degree of orr.

[Problem to be solved by the invention]

As described above, in order to improve the operating efficiency of ultra-high vacuum equipment, equipment with an air lock mechanism has been put into practical use.

However, in order to use it in a mass production process, it is necessary to further improve the operating rate, and countermeasures have been necessary.

[Means to solve the problem]

The above problem involves a first vacuum chamber having an ultra-high vacuum evacuation system,
In the vacuum apparatus with an aerodynamic mechanism, a second vacuum chamber including a movable mechanism within the first vacuum chamber and having a rough exhaust system is provided adjacent to the first vacuum chamber via a gate valve. A lid part for shielding the first vacuum chamber and the second vacuum chamber is provided on the movable part that moves, and a sealing frame is provided on the inner wall of the vacuum chamber near the gate valve. Constructing a vacuum device characterized in that when a certain mechanism section is moved to a first vacuum chamber and positioned, the lid section and the sealing frame are in close contact with each other via a sealing material to provide vacuum shielding. This can be solved by

[Effect]

In the present invention, when the mechanism section is moved into the first vacuum chamber, the surface area of the inner wall of the second vacuum chamber that affects the first vacuum chamber is substantially reduced, thereby increasing the influence on the first vacuum chamber. This reduces the inflow of gas, thereby improving the operating rate of the vacuum device.

FIGS. 1(A), 1(B), and 1(C) show the principle of the present invention. As shown in FIG. A cover 13 is provided, and the second vacuum chamber 7 near the gate valve 8 or the first
A sealing frame 14 with a sealing material 15 is provided in the vacuum chamber 2, and the mechanism part 3 is moved and positioned within the first vacuum chamber 2 as shown in FIGS. The lid portion 13 is crimped onto the sealing frame 14 via a sealing material 15 to provide vacuum shielding.

The sealing material 15 is generally an O-ring, and may be attached to the lid 13.

In addition, the same figure (B) shows the sealing frame 14 with the sealing material 15 attached.
is provided in the second vacuum chamber 7, and the same figure (C)
This is the case where the first vacuum chamber 2 is provided.

If such a method is adopted, when the gate valve 8 is opened and the mechanism section 3 is transferred to the first vacuum chamber 2, the entire inner wall of the second vacuum chamber 7 is conventionally attracted. Gas is the first
The vacuum chamber 2 was moved to the second vacuum chamber 2 and was suctioned and exhausted by the ultra-high vacuum evacuation system 1. However, when the plate-shaped lid 13 is used to shield the vacuum according to the present invention, the vacuum chamber 7 is attracted to the second vacuum chamber 7. Since the influence of dust generated in the vacuum chamber 7 can be suppressed to a minimum, the time required to transfer the mechanical part 3 to the second vacuum chamber 7, return it to the atmosphere, and then re-evacuate it can be reduced compared to conventional methods. The operating rate of the equipment can be improved.

〔Example〕

FIG. 2 shows an example in which the present invention is applied to a molecular beam source cell of a molecular beam crystal growth apparatus.

That is, the state shown in FIG. 2 shows a state in which the gate valve 17 is opened and the molecular beam source cell 18 is moved from the cell storage chamber 19 toward the growth chamber 2o where the substrate to be processed is installed and positioned.

The inner surface of the growth chamber 20 is covered with a shroud 21 and filled with liquid nitrogen (LN2), although not shown.
10 by evacuation with an ion pump through the opening.
It is possible to obtain a vacuum degree of -' to 10-10 Torr.

Next, the cell housing chamber 19 includes a turbo molecular pump 22 and an oil rotary pump 23, which are used to evacuate the cell housing chamber 19, and a leak valve 24.

Further, a source 25 is provided toward the tip of the molecular beam source cell 18 and is configured to be heated by a heater 26 .

The molecular beam source cell 18 is held by a first disk 29 and can move in the vertical direction in the figure using the first rod 28 as a kite.

Further, a lead wire 27 connected to the heater 26 is connected to the first disc 2.
9 and is insulated and attached using a current introduction terminal 30.

Further, the cell storage chamber 19 and the first disk 29 are connected to the bellows 3.
1, and by extension of this bellows 31, the molecular beam source cell 18 retreats to the cell storage chamber 19,
Molecular beam source cell 18 is closed by closing gate valve 17.
is configured to be isolated from the growth chamber 20.

In a molecular beam source cell having such a configuration, as a vacuum shielding mechanism according to the present invention, a ring-shaped member 32 made of stainless steel is welded to the cell housing chamber 19 close to the gate valve 17, and an O-ring made of Viton rubber is used. Seal material 3
3 was established.

Further, a second rod 34 is provided on the first disk 29,
A disk-shaped lid portion 35 was provided on top of this.

Note that the lid portion 35 is provided with a current introduction terminal 36 for passing the lead wire 27 therethrough.

After adopting such a structure, the molecular beam source cell 18 was moved to the cell housing chamber 19, the gate valve 17 was closed, and the leak valve 24 was opened to return the cell housing chamber 19 to atmospheric pressure.

Next, the molecular beam source cell 18 is filled with the source 25, the leak valve 24 is closed, the oil rotary pump 23 and the turbo molecular pump 22 are operated, and after evacuating for 3 hours to reach a vacuum level of 10-7 torr, the gate valve is closed. 17 was opened, and the molecular beam source cell I8 was moved until the lid part 35 came into close contact with the sealing material 33 of the link-like member 32.

The pressure in the growth chamber 20 rises while the molecular beam source cell is being moved, but after the vacuum shielding mechanism is activated, the pressure in the growth chamber 20 is reduced to 10'-9 Torr by the ultra-high vacuum evacuation system, making it possible to generate molecular beams again. It became a state.

By using this method, until now it took half a day to one day to pump out the growth chamber 20 (= molecular beam source cell 18), but as mentioned above, it is now possible to shorten the time to about 3 hours. became.

〔Effect of the invention〕

By implementing the present invention, in a vacuum apparatus with an air lock mechanism, the time from when the mechanical part is exposed to the atmosphere until it is used again in vacuum can be shortened, thereby improving the operating rate.

It is.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the principle of the present invention, FIG. 2 is a sectional view of a molecular beam source cell implementing the present invention, and FIG. 3 is a sectional view of a conventional vacuum device with an air lock mechanism. In the figure, 1 is an ultra-high vacuum evacuation system, 2 is a first vacuum chamber, 3 is a mechanical section, 6 is a rough evacuation system, 7 is a second vacuum chamber, 8 and 9 are gate valves, 10 is a bellows,
ll is a moving mechanism, 13 is a lid part,
14 is the sealing frame body, 15 is the sealing material, Kit) r side drawing house 3 drawing

Claims (3)

[Claims] (1) A first vacuum chamber (2) having an ultra-high vacuum evacuation system (1)
), and a mechanism part (3) movable into the first vacuum chamber (2).
) and a second vacuum chamber (7) having a rough exhaust system (6) is provided adjacently via a gate valve (8). 3) in the moving part (12) that moves.
A lid (13) is provided to shield the vacuum chamber (2) from the second vacuum chamber (7), and a sealing frame (14) is provided on the inner wall of the vacuum chamber near the gate valve (8). The mechanism section (3) in the second vacuum chamber (7) is moved to the first vacuum chamber (2), and in the positioned state, the lid section (13) and the sealing frame (14) are moved.
A vacuum device characterized in that the two are in close contact with each other via a sealing material (15) to provide vacuum shielding. (2) The sealing frame (14) described above is connected to the gate valve (8).
2. The vacuum device according to claim 1, wherein the vacuum device is provided on the inner wall of the second vacuum chamber (7) in the vicinity of the second vacuum chamber (7). (3) The sealing frame (14) described above is connected to the gate valve (8).
2. The vacuum device according to claim 1, wherein the vacuum device is provided on the inner wall of the first vacuum chamber (2) in the vicinity of the vacuum chamber (2).