JPH0660397B2 - Substrate exchange device in a vacuum chamber - Google Patents

Description

The present invention relates to a substrate exchanging device in a vacuum chamber.

[Conventional technology and its problems]

FIG. 11 shows an example of a conventional device for taking in a wafer from the atmosphere into the vacuum chamber.In this figure, this device passes through a gate valve or a partition valve (104) from the atmosphere by means such as a belt carrier (109). The wafer (106) sent into the vacuum chamber (101) is taken into an appropriate position in the chamber (101) by the belt transfer device (102) provided in the vacuum chamber (101), and the wafer (106) is separately provided. It has the function of being lifted above the belt position by the lifting device and then lowered onto another mechanism that has penetrated below the wafer (106).

Now, this will be described in more detail as follows. That is, as shown in FIG. 11A, the valve (10
The wafer (106) to be surface-treated which has passed through 4) into the vacuum chamber (101) is further conveyed to an appropriate position by the belt transfer device (102) provided in the vacuum chamber (101). Stop. The partition hubble (104) then closes and the vacuum chamber (1
01) The inside is evacuated to vacuum.

Next, as shown in FIG. 11B, the wafer pusher (108), which was positioned below the position where the wafer (106) of the belt (102) was placed at this time, maintained the vacuum seal through the bellows (105). Tama Wafer Vertical Cylinder (103)
To raise the wafer (106) above the belt surface.

Then, another wafer transfer mechanism (107) (for example, a fork transfer pickup or the like) enters below the wafer (106) below the wafer (106).

Next, as shown in FIG. 11C, the wafer pusher (108)
Is lowered and the wafer (106) is transferred onto another wafer transfer mechanism (107).

The above is the operation when the wafer (106) is taken into the vacuum chamber (101) from the atmosphere side, but conversely the processed wafer (106)
The procedure for taking out air to the atmosphere is the opposite. That is, in the above-mentioned conventional example, the already-processed wafer (106) is moved into the vacuum chamber (101), which is evacuated to a vacuum, by the mechanism (1).
07) and then vent the vacuum chamber (101),
The processed wafer (106) is taken out. Further, the unprocessed wafer (106) is taken into the vacuum chamber (101) and evacuated, and then the mechanism (107) carries the wafer into the processing chamber. During the process of taking out and taking in the wafer including the exhaust cycle of the above atmospheric vacuum, the processing chamber becomes a waiting time, which is inefficient.

A vacuum chamber for wafer loading to avoid this problem,
A method of separately providing a vacuum tank for taking in a wafer and a vacuum tank for taking out a wafer is often used, but this method complicates the structure of the apparatus.

When only one vacuum chamber is provided, rapid exhaust and rapid vent are usually required to accelerate the exhaust cycle of atmospheric vacuum, depending on the throughput of the device.
Recently, as the pattern size of I becomes finer, it is indispensable to suppress the adhesion of particles to the wafer as much as possible, and rapid evacuation and paint in a vacuum chamber where particles are likely to rise are not preferable.

[Problems to be solved by the invention]

The present invention overcomes the above-mentioned various drawbacks of the related art, and while a wafer (substrate) previously taken in is being processed in a processing chamber, the next wafer is taken in a vacuum chamber and further vacuum exhausted. It is an object of the present invention to provide a substrate exchanging device in a vacuum chamber which improves productivity by reducing the waiting time of the processing chamber by spraying the time required for vent exhaust from the wafer exchanging work in the processing chamber by completing the above. And

[Means for solving problems]

The above-mentioned object has a side wall portion having at least an opening for carrying in an unprocessed substrate from the atmosphere side and an opening for carrying out a processed substrate to the atmosphere side, and a vacuum in which these openings can be opened and closed by a gate valve, respectively. At least one stage of a support part, which comprises a substrate support disposed in the bath and an elevating drive part for driving the substrate support, and the unprocessed substrate can be placed on the substrate support. An unprocessed substrate supporting part and at least one adapted to mount the processed substrate
In a vacuum chamber, characterized in that a processed substrate support portion composed of stepped support portions is provided, and the substrate support body is driven by the elevating and lowering drive portion so as to be stopped at a plurality of predetermined positions in the vertical direction. Is achieved by the substrate exchange apparatus in.

[Work]

When the unprocessed substrate is placed on the unprocessed substrate support, the processed substrate is placed on the processed substrate support in a vacuum state, and then the unprocessed substrate is subjected to the required treatment in this state. Then, the inside of the vacuum chamber is brought to atmospheric pressure, and the processed substrate is carried out through the opening for carrying out the processed substrate from the vacuum tank to the atmosphere side. Then, the inside of the vacuum chamber is evacuated again, and the above operation is repeated.

Of the above series of operations, the atmospheric pressure in the vacuum chamber is set to atmospheric pressure, and the processed substrate is carried out from the processed substrate support unit to the required location on the atmosphere side, and the unprocessed substrate is transferred from the atmosphere side to the unprocessed substrate support unit. The work of loading and further exhausting the inside of the vacuum chamber is completed while the unprocessed substrate previously transferred to the processing chamber is being processed.

〔Example〕

Hereinafter, a CVD apparatus according to an embodiment of the present invention will be described with reference to the drawings.

Fig. 1 shows the whole of this device (1), but a pair of Cs on the left and right.
VD reaction chambers (2a) and (2b) are provided, and a buffer chamber (3) is provided between them. Buffer chamber (3) and both reaction chambers
Gate valves (16) and (17) are provided on a partition wall between (2a) and (2b), and a wafer is transferred through these gate valves. A wafer exchange chamber (5) according to the present invention is provided in front of the buffer chamber (3), and a gate valve (6)
Wafers are transferred between these chambers (3) and (5) via the.

A wafer transfer device (7) is provided in the buffer chamber (3), is provided with a transfer fork (8), is rotatable about a central axis (9) as shown by an arrow a, and It is expandable and contractible as shown by arrow b. Wafer exchange room (5)
Gate valves (10) (11) are also provided on both side walls of the, and an unprocessed wafer loading belt (12) is provided on this one side,
The wafer stock cassette (13) is automatically addressed at a predetermined timing, and is automatically taken out and carried into the wafer exchange chamber (5) by the belt (12). On the other hand, a processed wafer unloading belt (14) is provided to carry in the processed wafer stock cassette (15).

Next, the details of the wafer exchange chamber (5) will be described with reference to FIGS.

The wafer exchange chamber (5) is defined by a closed tank (21) as shown in FIG. 2, and has gate valves (10) and (11) (not shown in FIG. 2) and a rear wall on both side walls as described above. There are gate valves (6) on the wall, and these gate valves (6) (10) (1
Although the details of 1) will be described later, the chamber (23) is
The inside is sealed and the chamber (2
The inside of 3) is designed to be in a vacuum or reduced pressure state.

A substrate support (24) whose overall shape is clearly shown in FIG. 5 is arranged in the chamber (23), and a drive shaft (25) is fixed to the bottom surface of the substrate support (24). The bottom wall portion is hermetically inserted, extends into the atmosphere below, and is fixed to the screw engagement body (27). The drive shaft (25) is supported by a vacuum seal (26) so as to be vertically and airtightly slidable.

The screw engagement body (27) is screwed onto the pole screw (28), and the pulley (29) is fixed to the lower end portion of the screw (28). The motor (31) is fixed to the machine frame (not shown), and the belt (30) is wound between the pulley (32) fixed to the rotating shaft and the pulley (29). Motor (31)
Rotation of the ball screw (28) causes the screw engagement body (27) and hence the drive shaft (25) to move upward or downward. The motor (31) can rotate forward and backward, and the drive shaft (25) moves upward or downward depending on the direction of rotation. A height sensor device (36) is provided on one side of the screw engagement body (27) to detect each height position of the drive shaft (25), and the detection signal causes the motor (31) to drive-control. To be done.

As is well known, the ball screw (28) has a structure in which a ball is fitted in a screw groove, and the drive shaft (25) can be accurately raised or lowered to a predetermined position without backlash.

Cooling water inlets and outlets are formed in the small diameter portion of the screw engagement body (27), and the cooling water introducing tube (33) and the discharging tube (34) are connected thereto. Although not shown, the drive shaft (25) has an inlet path and an outlet path, and the substrate support (2
The base (37) of 4) communicates with the circulation path (35) formed in a meandering shape. The substrate support (24) is made of aluminum and has excellent thermal conductivity.

As mentioned above, there are gate valves on the three side walls of the closed tank (21).
(6), (10) and (11) are arranged, and are configured to hermetically close the openings (6a), (10a) and (11a) formed in these side wall portions. The gate valve (6) is shown in detail in FIG.

First, the gate valve (6) will be described with reference to FIG. 2. This is a structure that has already been widely used, and mainly includes a gate body (71) that opens and closes the opening (6a) and a parallel link ( 73) consists of a drive member (72) connected by (74), and the lower end part of the member (72) projects to the atmosphere through a vacuum seal (75) and is driven up and down by a cylinder device (76). It has become. In FIG. 2, the gate body (71) closes the opening (6a), but when the driving member (72) is lowered, the gate body (71) opens the opening (6a), and the driving member (7) is opened.
When 2) is raised, the opening (6a) is closed as shown in FIG.

Next, the details of the gate valves (10) and (11) will be described.
Since the gate valves 10 and 11 have the same structure, only the gate valve 10 will be described below with reference to FIGS. 3 and 4. FIG. 3 is a cross-sectional view of an essential part showing the operating state of the gate valve (10), in which the partition wall C that separates the atmospheric pressure space A from the vacuum chamber B (wafer exchange chamber (5)) is
A through hole (41) is provided, and the opening (10) on the vacuum chamber B side of the through hole (41) is formed.
a) is formed so as to be inclined upward.

The opening (10a) is provided with a valve plate (43) that opens and closes a valve seat portion formed around the opening (10a) so as to face the valve plate (43).
Is formed to have a diameter larger than that of the wafer (47) and penetrates the partition wall C on both sides of the through hole (41) and extends obliquely downward (44a) (44b) (see FIG. 3). Is connected to a fluid pressure (hydraulic pressure or pneumatic pressure) drive cylinder (45) provided below the atmospheric pressure space A. As shown in FIG. 4, the upper ends of the two rods (44a) and (44b) are O-rings (43) on both sides of the valve plate (43).
a) It is installed more inside and the rod and the valve plate are sealed by welding (43b) etc. so as not to leak from the joint. The lower end has a connecting member (44) that connects the two rods.
It is connected to the piston rod (44) of the cylinder (45) via c). In the figure, (45a) and (45b) are conduits for supplying or discharging pressure fluid to the cylinder (45), (12) and (48) are conveyor belts installed in the atmospheric pressure space A and the vacuum chamber B, respectively. (Four
9) shows a bearing push, and (50) shows an O-ring.

Since the valve plate (43) is configured as described above, in a normal state, that is, when the wafer is not fed, the valve plate (43) is in a reverse pressure state, that is, through the through hole (41) by the fluid pressure acting downward in the cylinder (45). The vacuum chamber side opening (10a) of the through hole (41) of the partition wall C is closed while pressure (atmospheric pressure) is acting in the valve opening direction. Therefore, the vacuum in the vacuum chamber B does not leak through the through hole (41).

Next, when the wafer (47) sent from the atmospheric pressure space A by the transfer belt (12) is transferred to the vacuum chamber B,
Change the fluid passage of the cylinder (45) to change the rod (44) (44a) (44
The valve plate (43) is raised via b) and the opening (10a) is released. At this time, since the through hole (41) is located in the middle portion of the two rods (44a) and (44b), it does not hinder the passage of the wafer (47) and the wafer is smoothly transferred to the vacuum chamber B. Be transferred to.

Next, when the wafer (47) has finished moving into the vacuum chamber B, the flow path of the cylinder (45) is switched again to lower the valve plate (43) and close the opening (10a). The wafer (47) transferred into the vacuum chamber B is transferred to a predetermined position on the substrate support (24) by the transfer belt (48).

According to this embodiment, the drive source for operating the valve plate is provided on the atmosphere side, and since all the sliding parts for operating the valve plate are located below the wafer, There is no risk that dust and the like will fall on the wafer. The vacuum chamber is also not contaminated by the drive source. In addition, since the valve plate and the rod are installed so as to be inclined with respect to the vacuum partition, it can be made compact and both wafer transfer belts in both chambers can be installed close to each other, resulting in a compact device. , Workability is improved accordingly. Since the valve plate seals the opening against the pressure difference in the reverse pressure state, it is necessary to select a valve plate with sufficient rigidity and a cylinder (drive source) with sufficient thrust. There is.

In the above-mentioned embodiment, the structure using the fluid pressure drive cylinder as the drive source of the valve plate has been described, but the structure is not limited to this, and a mechanical drive mechanism can be used instead.

Next, the details of the substrate support (24) will be described with reference to FIGS.

The substrate part (37) of the substrate support (24) is formed with a fork receiving recess (51) which is lower than the upper surface, and a pair of grooves (52a) (52b) is formed in relation to this. Has been done. Sixth
Although a part of the wafer transfer fork (8) is shown in the figure, the fork parts (8a) (8b) can be inserted into the grooves (52a) (52b).

Substrate support (24) in a direction perpendicular to the extending direction of the grooves (52a) (52b)
A pair of parallel notches (53a) and (53b) are formed on the wafer unloading side half of the entire height, and a pair of parallel notches (54a) (54a) (54a) ( 54b)
Although it is formed, as shown in FIGS. 6 and 8, it does not extend over the entire height at one end and the connecting portion (55)
Is covered by.

The belt conveyors (56a) (56b) (57a) (57b) are arranged vertically aligned with the notches (53a) (53b) (54a) (54b), which are the substrate supports (24). Notches when moving up and down (53a) (53b) (54
It is possible to pass a) (54b). The belt conveyors (56a), (56b) collectively constitute the belt conveyor (48) shown in FIG.

The upper part of the center of the substrate support (24) is an upper substrate support part (58) that is a partially annular unprocessed substrate support part, and a processed substrate support part that is concentrically and partially circular and is located below it. The lower substrate support part (59) is formed. Upper substrate support
(58) is an arcuate receiving surface (58a) (58) as shown in FIG.
b) consists of (58c) (58d) (58e) (58f), which are on the same level, but as shown by the alternate long and short dash line in FIG. 7 and FIG. An unprocessed wafer (47) is placed on the support part (58).
The lower substrate support (59) is on the same level, and each of them is a receiving surface (59a) (59b) (59c) (59d) (59e) (59f) that forms part of a circle.
(59g), and also has a surface-treated wafer (47) 'placed thereon, as also shown by the alternate long and short dash line in FIGS. 7 and 8.

A circular stepped hole recess (60) is formed on the bottom surface of the base plate portion (37), and the upper end portion of the drive shaft (25) described above is fitted therein,
Although not shown, they are fixed by screws or the like.

The configuration of this embodiment has been described above, but the operation will be described next.

10A to 10F show the respective height positions of the substrate support 24, according to this embodiment, the substrate support 24 can take five height positions. The level of the fork (8) that expands and contracts from the buffer chamber (3) and the belt conveyors (56a) (56b) (57a)
The level of (57b) is constant. Substrate support in FIG.
(24) The shape is shown in a simplified manner, and the upper stage support portion (58) and the lower stage support portion (59) of the above-mentioned wafer are on the upper arm and the lower arm of the U shape for the sake of clarity. These are indicated by U or D. (Ie U
And D are equivalent to the upper support part (58) and the lower support part (59). ) Now, it is assumed that the substrate support (24) is at the height position shown in FIG. 10A and the unprocessed wafer (47) is placed on the upper support U. Gate valves on both side walls (10) (11)
Shall be closed (gate valve (6) is open and in vacuum). In this state, the fork (8) extends from the buffer chamber (3) to place the processed wafer (47) 'thereon, and as shown in FIG. 10A, between the upper stage supporting part U and the lower stage supporting part D. Leading to.

The substrate support (24) is now raised to the position shown in Figure 10B. During this ascent, the processed wafer (47) 'is placed on the lower support D and stops there, and the substrate support (24) ascends and stops at the position 10B. But,
Here, the fork (8) is at the position shown (in the grooves (52a) (52b)) away from the processed wafer (47) '. At this position, the fork (8) retracts into the buffer chamber (3) as indicated by the arrow.

As shown in FIG. 10C, the substrate support (24) descends and again returns to the 10th position.
Take the same position as the height in Figure A. Then, the fork (8) extends from the buffer chamber (3) into the wafer exchange chamber (5) as shown by an arrow in FIG. The substrate support (24) moves downward and assumes the position shown in FIG. 10D. As a result, the unprocessed wafer (47) is carried by the fork (8). The fork (8) then retreats into the buffer room (3).

As shown in FIG. 10E, the substrate support (24) moves further downward. At this position, the gate valve is closed and the wafer exchange chamber (5) is returned to atmospheric pressure. And the gate valve (1
0) (11) can be opened.

When the substrate support 24 is stopped at the position shown in FIG. 10E, the processed wafer 47 is placed on the belt conveyors 56a and 56b as shown. Since the gate valves (10) and (11) are opened here, the processed wafer (47) 'is transferred by the belt conveyor (14) through the opening (11a), and the processed wafer cassette (15) Will be introduced to. The substrate support (24) moves further downward to the position shown in FIG. 10F. At this position, the belt conveyors (12) (57a) (57b) are located above the upper support U of the substrate support (24), but at this position they are taken out of the unprocessed wafer stock cassette (13). The wafer (47) is transferred by the belt conveyor (12) and opened (1
It is led to the inside of the wafer exchange chamber (5) through 0a). Then, the substrate support (24) moves upward and takes the position shown in FIG. 10A again. That is, the belt conveyors (56a) (56b) (57a) (57b) are located below the substrate support (24). Unprocessed Wafer (47)
Are placed on the upper stage U. Gate valve (10) (11) here
Is closed and the inside of the exchange chamber (5) is evacuated to a vacuum state. Then, as described at the beginning, the gate valve (6) is opened, and the fork (8) puts the processed wafer (47) 'into the wafer exchange chamber (5) from the baffle chamber (3) as shown in FIG. 10A. To the position. Hereinafter, the above operation is repeated.

Incidentally, when the wafer (47) 'which has been processed in the above steps is placed on the lower stage support portion D, the cooling water circulates in the substrate portion (37) of the substrate support (24), The processed and hot wafer (47) 'is cooled by heat exchange with this.
As a result, when the wafer is transferred from the wafer exchange chamber to the atmosphere, it can be stored in the cassette (15) in a stable state with almost no chemical change.

Although the embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications can be made based on the technical idea of the present invention.

For example, in the above embodiments, the unprocessed wafer (47) is placed on the upper stage support part (58), and the processed wafer (47) 'is placed on the lower stage support part (59). However, the number of steps of these supporting parts is further increased, and these are divided into two groups so that unprocessed wafers are placed in one group and processed in the other group. The wafer may be placed. Loading and unloading of processed wafers and unprocessed wafers may be performed in synchronization with each other. In this case, a belt conveyor for loading and unloading is required according to the number of stages, and multiple forks are required for loading and unloading wafers from the buffer chamber to the exchange chamber and vice versa. They may be integrated vertically and synchronized.

Further, in the above embodiments, the lower stage for supporting the processed wafer is cooled and the treated wafer is cooled.However, a heating means is further provided in the upper supporting part, and the unprocessed substrate is pretreated as a pretreatment. You may make it heat. The heated wafer is placed in the buffer chamber (3) and the reaction chamber (2a) or (2b).
May be introduced into.

Further, in the substrate support (24), a heat insulating material is interposed between the upper and lower supporting parts, the upper supporting part is provided with a heating means, and the lower supporting part is provided with a cooling means as in the above embodiment. May be provided.

Further, although the height positions of the substrate support (24) are set to five in the above-mentioned embodiments, the number is further increased to carry in / out the wafer at a position of each height by a method other than the above-mentioned wafer loading / unloading method. It may be performed. In this case, the level of the belt conveyor and the fork as the carry-in / carry-out device is not limited to one as in the embodiment, but a plurality of top and bottom,
It may be provided. Further, the carrying-in and carrying-out means are not limited to the fork and the belt conveyor, and various known means can be applied. Further, in the above embodiments, the processed wafer and the unprocessed wafer are carried in and out through separate gate valves, but this may be carried out through one ordinary gate valve.

〔The invention's effect〕

As described above, according to the substrate exchanging apparatus in the vacuum chamber of the present invention, the processed wafer is carried out from the wafer exchanging chamber to a predetermined position in the atmosphere and the wafer is transferred from the prescribed position in the atmosphere to the wafer exchanging chamber. It is possible to carry out the work of loading the wafer, and the associated vent and exhaust work in parallel while the other wafers are being processed in the processing chamber, minimizing the time required for the wafer exchange work in the processing chamber. Further, it is possible to perform the pretreatment of the untreated substrate or the cooling of the heated substrate at the same time as the substrate exchanging work, and it is possible to further improve the productivity.

[Brief description of drawings]

1 is a plan view showing the arrangement of the entire CVD apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view of the substrate exchanging apparatus in the above apparatus, and FIG. 3 is a gate valve in the substrate exchanging apparatus. FIG. 4 is a sectional view showing the details of FIG. 4, FIG. 4 is a partial perspective view of FIG. 3, FIG. 5 is an enlarged perspective view of a substrate support in the same substrate exchanging device, and FIG. 7 is a sectional view taken along line VII-VII in FIG. 6, and FIG. 8 is VIII in FIG.
-VIII sectional view taken along the line, FIG. 9 is a sectional view taken along the line IX-IX in FIG. 6, and FIGS. 10A to 10F are side views of essential parts for showing the operation of this embodiment. FIG. 11 is a sectional view showing a conventional substrate exchanging device. In the figure, (5) -wafer exchange chamber (6) (10) (11) -gate valve (24) -substrate support (58) -substrate upper support (59) -substrate lower support Department

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP 61-192334 (JP, A) JP 61-113767 (JP, A) JP 61-47069 (JP, U)

Claims (5)

[Claims] 1. A sidewall having at least an opening for carrying in unprocessed darkness from the atmosphere side and an opening for carrying out a treated substrate to the atmosphere side is formed, and these openings can be opened and closed by a gate valve, respectively. A substrate support provided in a vacuum chamber and an elevating / lowering drive unit for driving the substrate support, and at least one stage of support on which the unprocessed substrate can be placed. Unprocessed substrate support part consisting of a part and at least one adapted to mount the processed substrate
In a vacuum chamber, characterized in that a processed substrate support portion composed of stepped support portions is provided, and the substrate support body is driven by the elevating and lowering drive portion so as to be stopped at a plurality of predetermined positions in the vertical direction. Substrate exchanging device. 2. The substrate exchanging device in the vacuum chamber according to claim 1, wherein the processed substrate support portion of the substrate support is provided with cooling means. 3. A substrate exchanging device in a vacuum chamber according to claim 1, wherein said untreated substrate supporting portion of said substrate support is provided with heating means. 4. The gate valve is provided with a through hole provided in a side wall portion of the vacuum chamber with an opening on the vacuum chamber side inclined upward, and a valve plate for opening and closing the opening is provided on a side wall of the vacuum chamber. Through the rod that has penetrated through and is obliquely pulled out to the atmosphere side,
2. The substrate exchanging device in the vacuum chamber according to claim 1, wherein the vacuum chamber communicates with or is cut off from the atmosphere by moving up and down by a drive source installed on the atmosphere side. 5. The valve plate is formed on the atmosphere side through two rods which are formed such that the length between both sides thereof is larger than the diameter of the substrate, and which are attached to the both sides and pulled out to the atmosphere side. Substrate exchanging device in the vacuum chamber according to the fourth item, wherein the substrate exchanging device is connected to the cylinder.