JPH0612605Y2 - End station for ion implanter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an end station for an ion implantation apparatus which is improved so as to be suitable for, for example, a dual type end station.

[Conventional technology]

FIG. 8 is a schematic diagram of a conventional end station.
The unimplanted wafer 4 stored in the cassette 12 in the atmosphere is evacuated to the first air lock chamber 5
After passing through a, the wafer is conveyed to an injection chamber 1 that is evacuated to a vacuum and mounted on, for example, a platen (that is, a holder on which the wafer 4 is mounted) 2. Then, the platen 2 is erected by the actuator 3, and the ion beam I is applied to the wafer 4 thereon.
B is irradiated to perform ion implantation. The ion implantation chamber 1 is evacuated to a vacuum of, for example, 10 ⁻⁵ to 10 ⁻⁷ Torr during ion implantation.

After the ion implantation, the platen 2 is returned to the horizontal state, and the implanted wafer 4 is evacuated to the second air lock chamber 5b.
After that, it is stored in, for example, the cassette 13 in the atmosphere.
Reference numerals 6 to 9 in the drawing are gate valves for partitioning a vacuum, reference numerals 16 to 20 are transfer belts for transferring the wafer 4, and reference numeral 14 is an airlock chamber 5.
It is a vacuum pump for vacuuming a and 5b. A vacuum pump for evacuating the injection chamber 1 is not shown.

[Problems to be solved by the invention]

In recent years, in order to improve throughput (wafer processing capacity per unit time), for example, an ion beam is deflected into two, two end stations are provided, and two so-called dual type in which ion implantation is performed in parallel is performed. End stations are receiving attention.

In the conventional end station 30 described above, the two airlock chambers 5a and 5b are arranged on the left and right sides of the implantation chamber 1, and the flow of the wafer 4 is perpendicular to the ion beam IB. If an attempt is made to construct a dual type end station using two different end stations 30, as shown in FIG. 9, the two end stations 30a and 30b mechanically interfere with each other, which is unsuccessful. If you try to solve this,
The deflection angle θ of the ion beam IB by the deflecting means 40 must be extremely large, or the distance between the deflecting means 40 and the end stations 30a and 30b must be extremely large. And then unrealistic.

Therefore, the main purpose of the present invention is to provide a compact end station suitable for a dual type.

[Means for solving problems]

The end station of the present invention comprises a common airlock chamber for the first and second airlock chambers, and first and second transport chambers capable of independently and simultaneously transporting wafers therein. Belts are provided side by side, and an operation of receiving a wafer from the first transfer belt in the common airlock chamber and transferring it to the ion implantation site and an operation of transferring the wafer in the opposite direction are performed in the implantation chamber. The reversible third transfer belt and the fourth transfer belt for transferring the wafer from the implantation chamber to the second transfer belt in the common airlock chamber are independent of each other and A direction control means is provided which has a member that can be simultaneously transferred and a fifth transfer belt that moves up and down and receives the wafer from the third transfer belt and transfers it to the fourth transfer belt. That.

[Action]

The first and second transfer belts in one common airlock chamber allow transfer of unimplanted wafers from the atmosphere to the injection chamber and transfer of injected wafers from the injection chamber to the atmosphere. Each is done. In the implantation chamber, the direction control means controls the flow of the wafer between the ion implantation location and the first and second transfer belts in the airlock chamber. By doing so, this end station is made compact.

〔Example〕

FIG. 1 is a schematic diagram of an end station according to an embodiment of the present invention. The same parts as those in FIG. 8 are designated by the same reference numerals and the description thereof will be omitted.

In the end station 70 of this embodiment, the air lock chambers 5a and 5b described above are integrated into a common air lock chamber 50. In the air lock chamber 50, a first transfer belt 21 and a second transfer belt 22 that can transfer the wafers 4 independently of each other and simultaneously are arranged in parallel. In addition, the air lock chamber 50 includes the gate valve 10
And 11 are in contact with the atmosphere side and the injection chamber 60. In front of the gate valve 10, the above-mentioned cassette 1
2 and 13 are provided side by side.

Further, in the implantation chamber 60, an operation of receiving the wafer 4 from the transportation belt 21 in the airlock chamber 50 and transporting it to the platen 2 which is an ion implantation site and an operation of transporting the wafer 4 in the opposite direction are performed. Reversible third transfer belt 23 and fourth transfer belt 2 for transferring wafer 4 from transfer chamber 60 to transfer belt 22 in air lock chamber 50.
5, a direction in which a conveyor belt 23 can be conveyed independently of each other and at the same time, and an elevating fifth conveyor belt 24 that receives the wafer 4 from the conveyor belt 23 and transfers the wafer 4 to the conveyor belt 25. A control means 26 is provided.

Next, the operation of the end station 70 of this embodiment will be described with reference to FIGS.

First, referring to FIG. 1, the platen 2 is standing vertically and is in the process of ion implantation into a wafer 4 mounted thereon,
Further, it is assumed that the unimplanted wafer 4 is transferred from the atmosphere to the position C of the airlock chamber 50. And the wafer 40
When the ion implantation is completed, the gate valve 10 which has been open until then is closed, and the vacuum pump 14 starts the evacuation of the airlock chamber 50.

Next, referring to FIG. 2, the platen 2 is rotated to a horizontal position by the actuator 3 while the evacuation of the air lock chamber 50 is continued, and the wafer 4 having been implanted is transferred by the transfer belt 23 and Is rotated in the reverse direction to that shown in FIG. 4, which will be described later, so that the platen 2 is conveyed from position G to position E.

Next, referring to FIG. 3, when the evacuation of air lock chamber 50 is completed, transfer belt 24 is raised and driven to transfer wafer 4 from position E to position F. Then, the conveyor belt 24 is lowered.

Next, referring to FIG. 4, the gate valve 11 is opened to transfer the wafer 4 at the position F to the position D in the airlock chamber 50 by the transfer belts 25 and 22 and, at the same time, the uninjected wafer at the position C. The wafer 4 is transferred to the position G on the platen 2 by the transfer belts 21 and 23 and mounted. As described above, in the end station 70, the unimplanted wafer 4 is received from the conveyor belt 21 in the airlock chamber 50 and is transferred to the platen 2, and the already-implanted wafer 4 is injected from the injection chamber 60 into the airlock chamber 50. Since the transfer to the inner transfer belt 22 can be carried out at the same time, a waiting time is not generated unlike the case where these carrying-in and carrying-out are performed alternately, and accordingly, the handling time of the wafer 4 is shortened, so that the throughput is improved. improves.

Next, referring to FIG. 5, the platen 2 is attached to the actuator 3
And the gate valve 11 is closed to start ion implantation into the unimplanted wafer 4. At the same time, the vent valve 15 is opened and the air lock chamber 5 is opened.
For example, nitrogen gas is injected into 0 to bring the airlock chamber 50 to the atmospheric pressure.

Lastly, referring to FIG. 6, while the ion implantation into the wafer 4 in the implantation chamber 60 is continued, the gate valve 10 is opened, and unimplanted at the position A in the cassette 12 provided in the atmosphere. The wafer 4 is transferred to the position C of the airlock chamber 50 by the transfer belts 16 and 21, and at the same time, the implanted wafer 4 in the position D of the airlock chamber 50 is provided to the atmosphere by the transfer belts 22 and 20. Cassette 13
To position B. As a result, the state returns to the state shown in FIG. Thus, in this end station 70,
Since it is possible to carry in the uninjected wafer 4 from the atmosphere into the airlock chamber 50 and to carry out the implanted wafer 4 from the airlock chamber 50 into the atmosphere at the same time, these wafers can be carried in and out. No waiting time is generated unlike in the case of performing alternately, and the handling time of the wafer 4 is shortened by that much, so that the throughput is improved.

After that, the above operation may be repeated as necessary.

The degree of vacuum of the airlock chamber 50 is determined in consideration of its volume, ion implantation time, the capacity of the vacuum pump 14, the influence on the implantation chamber 60, etc., and is usually 10 ⁻² to 10 ⁻⁷ T.
It may be about orr.

As described above, the end station 70 of this embodiment is
Since only one air lock chamber 50 is required, the air lock chamber 50 can be made small and compact, and the flow of the wafer 4 can be made parallel to the ion beam IB. Therefore, even if a dual type end station is configured by using two such end stations 70,
As shown in the figure, two end stations 70a, 7
0b does not mechanically interfere. Therefore, the dual type end station can be constructed very compactly. Of course, it is also possible to deflect the ion beam IB into three or more and to provide three or more end stations 70.

[Effect of device]

As described above, the end station of the present invention has only one airlock chamber and can save the wasted space as much as possible, so that the end station can be made small and compact. Therefore, for example, the dual type can be easily adopted. . Further, since only one air lock chamber is required, the number of valves associated therewith can be reduced and the control system thereof can be simplified.

Moreover, the transfer of the wafer from the forward path to the return path in the implantation chamber is performed by the fifth elevating transfer belt, which makes it possible to transfer the wafer to the third side on both sides as compared with the case of using a transfer arm. Since the space between the fourth conveyor belt and the fourth conveyor belt can be made small, the injection chamber can be made small and compact, which in turn contributes to making the end station small and compact.

In addition, since the third conveyor belt is commonly used for the forward path and the return path in the injection chamber, the belt drive motor at that portion is
You can also get the effect that you can do it individually.

Further, since it is possible to carry in the uninjected wafer from the atmosphere into the airlock chamber and carry out the injected wafer from the airlock chamber into the atmosphere at the same time, and at the same time, from the airlock chamber to the implantation chamber. Since it is possible to carry in the unimplanted wafers and the implanted wafers from the implantation chamber to the airlock chamber at the same time, a waiting time does not occur unlike the case where these transportations are performed alternately. The wafer handling time is shortened and the throughput is improved.

Therefore, according to this invention, it is possible to realize a small and compact end station having high throughput.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an end station according to an embodiment of the present invention. 2 to 6 are views for explaining the operation of the present invention. FIG. 7 is a schematic diagram of a dual type end station using two end stations of FIG. FIG. 8 is a schematic diagram of a conventional end station. FIG. 9 is a schematic diagram when two end stations of FIG. 8 are used to form a dual type end station. 4 ... Wafer, 21 ... First conveyor belt, 22 ... Second conveyor belt, 23 ... Third conveyor belt, 24 ...
Fifth conveyor belt, 25 ... Fourth conveyor belt, 26 ...
... Direction control means, 50 ... Air lock chamber, 60 ... Injection chamber, 70 ... End station of the embodiment.

Claims (1)

[Scope of utility model registration request] 1. A wafer in the atmosphere is transferred through a first air lock chamber that is evacuated to a vacuum to an injection chamber that is evacuated to a vacuum,
Therefore, after the ion implantation, in the end station for the ion implantation device that is taken out into the atmosphere through the second airlock chamber that is evacuated to vacuum, the first and second airlock chambers are combined into one common airlock chamber. And in it,
First and second transfer belts capable of simultaneously and independently transferring the wafers are arranged side by side, and the wafer is received from the first transfer belt in the common airlock chamber in the implantation chamber to ionize the wafers. A third reversible conveyor belt that carries out the operation of carrying the wafer to the implantation location and the operation of carrying the wafer in the opposite direction, and a fourth conveyor belt that carries the wafer from the implantation chamber to the second transportation belt in the common airlock chamber. Of the third transfer belt, which is independent of the third transfer belt and can be transferred at the same time, and the fifth lifting type which receives the wafer from the third transfer belt and transfers it to the fourth transfer belt. An end station for an ion implantation device, characterized in that it is provided with a direction control means having a conveyor belt.