JPH0533093B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vacuum apparatus for processing semiconductor wafers in a vacuum state in, for example, semiconductor manufacturing. The present invention relates to a vacuum apparatus in which an airtight preliminary chamber is formed in the vicinity of an entrance/exit only before processing, after processing a workpiece, and before transporting the workpiece from the vacuum apparatus.

[Conventional technology]

In recent years, equipment using conventional technology has been expanding its application fields more and more, and in particular, ion equipment, plasma equipment, and electron beam application equipment, where vacuum technology greatly influences equipment performance, are making remarkable advances into the semiconductor manufacturing field. There is.

In such vacuum apparatuses, apparatuses equipped with an airtight preliminary chamber are becoming mainstream in order to improve productivity and prevent contamination of impurities.

FIG. 3 schematically shows an example of a conventional vacuum apparatus equipped with an airtight preliminary chamber. is isolated. The partition wall 2 is provided with an opening 6 equipped with a sealing valve 5.
Further, an opening 8 with a lid 7 is provided in the container wall constituting the airtight preliminary chamber 4. The valve 5 is normally in a closed state, and the processing chamber 3 is evacuated and maintained in a vacuum state. Note that 9 is a sealing member.

In the above configuration, an unprocessed workpiece placed on the tray 10, for example, a semiconductor wafer 11
is carried into the airtight preliminary chamber 4 through the opening 8 of the lid 7. Next, the lid 7 is closed and the airtight preliminary chamber 4 is closed.
After the inside is evacuated to the same vacuum state as the processing chamber 3, the valve 5 is opened and the semiconductor wafer 11 is transferred to the processing chamber 3 through the opening 6. Next, the valve 5 is closed and a predetermined processing process is performed on the semiconductor wafer 11.

The processed semiconductor wafer 11 is transferred to the airtight preliminary chamber 4 through the opening 6 of the valve 5 while the airtight preliminary chamber 4 is evacuated to the same level as the processing chamber 3.
will be returned to. After the valve 5 is closed, a gas such as nitrogen gas is introduced into the airtight preliminary chamber 4, and the processed semiconductor wafer 11 is carried out through the opening 8 of the lid 7.

In the vacuum apparatus shown in FIG. 3, by providing the airtight preliminary chamber 4, the inside of the processing chamber 3 can always be kept in a vacuum regardless of the loading and unloading of semiconductor wafers 11. This prevents atmospheric air from entering the tank and maintains the purity of the gas required for processing.

Next, FIGS. 4 and 5 schematically show a conventional vacuum apparatus of the type in which a preliminary chamber of small volume is formed as required, and a semiconductor wafer 11 is slid in the axial direction. It is attached to a holder 13 that is attached to a rotating shaft 12 that can be rotated. Holder 13
Two semiconductor wafers 11 are mounted on the rotating shaft 12 with an angular spacing of 180° between them. An opening 8 for loading and unloading the semiconductor wafer 11 is provided at a position that matches the semiconductor wafer 11 on the opposite side of the processing chamber 3, and the holder 13 is inserted into the chamber wall provided with the opening 8. 1
A sealing plate 15 is mounted on a slidable shaft 16 for pressing against the semiconductor wafer 11 to form a small volume hermetic reserve chamber 4 around the semiconductor wafer 11. In FIG. 4, the seal plate 15 is in the inoperative position, so that the seal plate 15 is not in contact with the holder 13, and the holder 13 is rotatable. The inside of the chamber 1 is maintained in a vacuum state, and when the holder 13 rotates 180° in this state, the unprocessed semiconductor wafer 11 on the opening 8 side is transported to the processing chamber 3, and the processed semiconductor wafer is transferred to the processing chamber 3. 11 is brought to the position of the opening 8. Next, slide the shaft 16,
The holder 13 is attached to the vessel wall 14 by the seal plate 15.
to press against. As a result, as shown in FIG. 5, an airtight preliminary chamber 4 surrounded by the lid 7, holder 13, and seal plate 15 is formed. Next, a gas such as nitrogen gas is introduced into this airtight preliminary chamber 4, the lid 7 is opened, the processed semiconductor wafer 11 is replaced with an unprocessed semiconductor wafer 11, and the lid 7 is opened again.
is closed and the airtight preliminary chamber 4 is evacuated. Airtight spare room 4
After the inside becomes the same vacuum state as the inside of the processing chamber 3, if the seal plate 15 is retreated, the holder 13 becomes rotatable again.

As is clear from the above explanation, in the vacuum apparatus shown in FIGS. 4 and 5, only after the unprocessed semiconductor wafer 11 is carried in, before processing, and before the processed semiconductor wafer 11 is carried out, An airtight preliminary chamber 4 is formed, which not only prevents atmospheric air from entering the processing chamber 3, but also provides an exchange mechanism for unprocessed semiconductor wafers 11 and processed semiconductor wafers 11, making it even more airtight. Since the volume of the preliminary chamber 4 is extremely small, the evacuation time of this airtight preliminary chamber is much shorter than in the vacuum state shown in FIG. 1, thereby improving productivity.

[Problem that the invention seeks to solve]

By the way, in the conventional vacuum apparatus shown in FIG. 3, since the volume of the airtight preliminary chamber 4 is large, it takes time to evacuate the airtight preliminary chamber 4, which has the disadvantage of poor productivity. is greatly improved by the vacuum apparatus shown in FIGS. 4 and 5. However, in the vacuum apparatus shown in FIGS. 4 and 5, when the atmosphere enters the airtight preliminary chamber 4, atmospheric pressure is applied to the seal plate 15 in a direction that presses it to the right in the figure. Therefore, there was a drawback that an extremely large force was required to hold the seal plate 15. Furthermore, since the surface of the workpiece opposite to the opening 8 is covered with the seal plate 15, there is also the drawback that it is difficult to provide means for heating the workpiece, for example, on both sides.

[Means for solving problems]

The present invention has been made in order to effectively solve the above-mentioned drawbacks of this type of vacuum apparatus. The above-mentioned problem has been solved by providing a ring-shaped body and forming an air-tight peripheral wall of the air-tight preliminary chamber with the ring-shaped body when the ring-shaped body is in an extended state.

[Effect]

The annular body is composed of metal bellows, etc.
When this annular body is in a contracted state, an airtight preliminary chamber is not formed, and the workpiece can be transferred between the loading/unloading entrance and the processing chamber, and an airtight preliminary chamber is formed only when the annular body is expanded. be done.

〔Example〕

1 and 2 show an embodiment of the vacuum apparatus according to the present invention, and this embodiment is similar to the airtight prechamber formation of the conventional vacuum apparatus described with reference to FIGS. 4 and 5. This is a structural improvement. Therefore,
Except for the structure near the opening for carrying in and out of the workpiece, the workpiece holding mechanism and exchange mechanism are almost the same as those in FIGS. 4 and 5, so illustration and explanation of this overall structure will be omitted. However, only the essential parts are shown in FIGS. 1 and 2.

In this embodiment, an example will be described in which a metal bellows is used as the airtight annular body, and an annular body 21 surrounding the periphery of the opening 8 is attached to the vessel wall 14. This annular body 21 includes an airtight metal inner bellows 22, an airtight metal outer bellows 23 coaxially arranged outside the inner bellows 22 at a predetermined distance, and inner and outer bellows 22 and 23. A flange 24 is attached to the tip of the flange 24 to interconnect them. The base ends of the bellows 22 and 23 are fixed to the inner wall surface of the vessel wall 14, and a sealed space 25 is formed by the vessel wall 14, the flange 24, and both bellows 22 and 23. Compressed air is introduced into this space 25 through a pipe 26 provided through the vessel wall 14, and when pressurized, the bellows 22 and 23 expand in the axial direction, causing the flange 24 to open at the opening 8. It is designed to move in the opposite direction (to the right in the figure).

On the other hand, a window 29 in which a transparent quartz glass 28 is fitted is provided in the vessel wall 27 facing the opening 8, and the quartz glass 28 is fixed by a fixing ring 30 and a seal ring 31. Also window 2
9 has an infrared lamp 32 and a reflective mirror 33 on the outside.
A heating means is provided to heat the semiconductor wafer 11 held in the holder 13 through the window 29. semiconductor wafer 1
1 is attached to the holder 13 by suitable means such as a pawl or a spring.

The configuration of one embodiment of the vacuum apparatus according to the present invention has been described above, and now its operation will be explained.

Initially, bellows 22 and 23 are in a contracted state as shown in FIG.
4 is not in contact with the holder 13, and the holder 13 is in a rotatable state. The interior of the chamber 1 is maintained in a vacuum state, and predetermined processing is performed on the semiconductor wafers 11 within the processing chamber. When this process is completed, the holder 13 is rotated 180 degrees and the processed semiconductor wafer 11 is carried to the position of the opening 8.
The unprocessed semiconductor wafer 11 at the position is carried into the processing chamber. Next, bellows 22 and 23
Pressure is applied to the space 25 between the bellows 22 and 2.
3 and move the flange 24 to the window 29 side. As the flange 24 moves, the holder 13 is also pushed by the flange 24 and the seal ring 31
is crimped. In this case, the window 2 of the holder 13
Other means for movement to the 9 side may be used.
By press-fitting the flange 24 to the seal ring 31 and press-fitting the flange 24 to the holder 13, an air-tight preliminary chamber 4 having the bellows 22 and 23 as an air-tight peripheral wall is formed.

After the airtight preliminary chamber 4 is formed in this way,
A gas such as nitrogen gas is introduced into the airtight preliminary chamber 4, the lid 7 is opened, the processed semiconductor wafer 11 is removed from the holder 13, and an unprocessed semiconductor wafer 11 is set in the holder 13 instead. Next, the lid 7 is closed and the airtight preliminary chamber 4 is evacuated, and when the vacuum state is reached, the space 25 between the bellows 22 and 23 is
The bellows 22 and 23 are contracted by reducing the pressure.
The flange 24 is moved toward the opening 8 side. This makes the holder 13 rotatable again.

〔Effect of the invention〕

According to the present invention, it is clear that an airtight preliminary chamber having a small volume and therefore requiring no time for evacuation can be obtained with a simple configuration, but the power for forming this airtight preliminary chamber is It is also clear that much smaller force is required compared to the conventional one. In addition, a means for forming an airtight preliminary chamber is provided at the opening for carrying in and out the workpiece, but since the means is constituted by an annular body, there is an advantage that it cannot prevent the carrying in and out of the workpiece. . Since the annular body is provided on the opening side in this way, a heating means for heating the workpiece, for example, can also be provided on the opposite side to the opening side. Furthermore, since the mechanism for forming the airtight preliminary chamber does not have a movable mechanism with friction parts,
It has many advantages such as no fear of dust generation, which is particularly important in semiconductor manufacturing equipment.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of the essential parts of a vacuum device according to an embodiment of the present invention, FIG.
FIG. 5 is a schematic cross-sectional view showing a conventional vacuum device. In the figure, 1 is a container body, 3 is a processing chamber, 4 is an airtight preliminary chamber, 7 is a lid, 8 is an opening for carrying in and out of workpieces, 11 is a semiconductor wafer, 13 is a holder, 21 is an annular body,
22 is the inner bellows, 23 is the outer bellows, 24
is a flange, 25 is a space, 26 is a pipe, 28 is quartz glass, 29 is a window, 30 is a fixing ring, 31
3 represents a seal ring, 32 represents an infrared lamp, and 33 represents a reflecting mirror.

Claims (1)

[Scope of Claims] 1. A processing chamber for processing a workpiece in a vacuum state, an opening for carrying the workpiece into and out of the processing chamber, and a processing chamber for processing the workpiece after carrying the workpiece into and out of the processing chamber. and an airtight preliminary chamber formed in the vicinity of the opening only after processing the workpiece and before transporting the workpiece, wherein the opening has a coaxial relationship with the opening and an airtight preliminary chamber is formed in the axial direction inside the opening. An airtight annular body that can be expanded and contracted by pressurizing or depressurizing the space to be formed is provided, and when this annular body is expanded, it forms an airtight wall of the preliminary airtight chamber. vacuum equipment. 2. The space formed within the airtight annular body is sealed by a flange attached to the tip of the airtight annular body so as to connect these parts. vacuum equipment.