JP4356480B2 - Transport equipment and semiconductor manufacturing equipment - Google Patents

Description

  The present invention relates to a transfer apparatus that carries a substrate to be processed into and out of a semiconductor processing apparatus, and more particularly to a transfer apparatus for a single wafer processing apparatus that performs processing in a vacuum environment.

Generally, a load-lock type semiconductor manufacturing apparatus includes a load-lock chamber, a transfer chamber, and a processing chamber connected to the transfer chamber. A transfer robot is installed in the transfer chamber, and a substrate to be processed is transferred between the load lock chamber and the processing chamber.
On the other hand, there are a batch type and a single wafer type as a form of substrate processing in a semiconductor manufacturing apparatus. The batch method is a method of processing a plurality of substrates at a time in the processing chamber, whereas the single wafer method is a method of processing the substrates one by one in the processing chamber. The batch type is more productive because the number of processed sheets per process is larger, but the single wafer type is more advantageous for quality improvement and the recent market demand for high-mix low-volume production.
Therefore, in order to improve the throughput of the single wafer processing apparatus, a processing apparatus called a cluster type has been developed. Corresponding to the cluster type, the transfer robot adopts a double fork structure that can mount two substrates or a double arm structure with two arms, and the next substrate while processing the substrate in the processing chamber. A transfer device has been developed that allows the unprocessed substrate and the processed substrate to be quickly replaced while waiting.

However, as a result, the transfer robot is increased in size and complexity, resulting in an increase in the size of the transfer chamber, resulting in an increase in cost and footprint.
In general, cluster type processing equipment has a polygonal transfer chamber and a number of processing chambers installed around it. One chamber itself, a so-called single chamber manufacturing apparatus, has been demanded.
The transfer device for a single chamber manufacturing apparatus is mainly required to have characteristics such as low cost and small footprint.

As a conventional technique, a conveying apparatus for responding to such a request is disclosed (for example, Patent Document 1). This will be briefly described below with reference to the drawings. FIG. 8 is a diagram showing a conventional semiconductor manufacturing apparatus disclosed in Patent Document 1. In FIG.
FIG. 8A is a top view and FIG. 8B is a side view. In FIG. 8, 101 is a processing chamber, 102 is a load lock chamber connected to the processing chamber 101 via a gate valve, and 103 is a wafer transfer arm having a link type single arm shaft. As shown in the figure, the wafer transfer arm 103 is installed in the load lock chamber 102 and carries a semiconductor wafer (substrate) transfer operation between the processing chamber 101 and the load lock chamber 102.
Further, the processing chamber 101 has a buffer mechanism for supporting the substrate by supporting means 104 and 105 that rotate in the horizontal direction and move up and down, and process unprocessed substrates and processed substrates as needed. The chamber 101 is temporarily held, and the processed substrate and the unprocessed substrate in the load lock chamber 102 are switched while processing is performed in the processing chamber 101.

JP 2003-37146 A

However, in the conventional transfer device, since there is only one gate valve between the processing chamber and the load lock chamber, if corrosive gas is used in the processing chamber, if gas enters the load lock chamber, the outside of the device However, there was a problem that the gas leaked out.
In addition, since the transfer arm is installed in the load lock chamber, the capacity of the load lock chamber is increased, and accordingly, the pump for evacuating and returning to the atmosphere in the load lock chamber is enlarged, resulting in an increase in cost. there were. Further, there is a problem that the footprint increases due to the enlargement of the load lock chamber.
In addition, it took time to evacuate and return to the atmosphere, and furthermore, only one wafer could be buffered, so there was a limit to improving throughput.
The present invention has been made in view of such problems, and provides a transfer device for a single chamber manufacturing apparatus that can prevent the outflow of corrosive gas, realize a low cost, small footprint, and improve throughput. For the purpose.

In order to solve the above problem, the present invention is configured as follows.
The invention according to claim 1 is a transfer apparatus for carrying in and out a substrate to be processed with respect to a single-wafer semiconductor processing apparatus that performs processing in a vacuum environment, wherein the transfer apparatus mounts one substrate. And a first buffer that performs upper and lower two-position operations, and repeats a vacuum or an atmospheric state so that the substrate placed on the first buffer is external to the transfer device in the atmospheric state. The load lock chamber that communicates with the load lock chamber, and the load lock chamber and the processing chamber are connected between the load lock chamber and the processing chamber so that the load lock chamber and the processing apparatus are arranged in a straight line. A transfer chamber, a horizontal articulated robot that is provided in the transfer chamber and transfers the substrate to the load lock chamber or the processing apparatus in a vacuum state; and the horizontal articulated robot provided in the transfer chamber. A bot and a second buffer capable of transmitting and receiving the substrate, wherein the horizontal articulated robot has one single arm, and the fork that rotates at the tip of the single arm independently of the single arm. The second buffer includes upper and lower two-stage plates made up of first and second plates, and each of the first and second plates is operated by performing upper, middle, and lower three-position operations. Conveying device configured to be able to place the substrate, wherein the second buffer is installed so that the center position of the upper and lower two-stage plate is placed at the center of rotation of the single arm. It was.
According to a second aspect of the present invention, there is provided the transfer device according to the first aspect in which an air cylinder that performs a two-position operation is used as a mechanism for the two-position operation above and below the first buffer.
According to a third aspect of the present invention, there is provided the transport apparatus according to the first aspect, wherein an air cylinder that performs a three-position operation is used as a mechanism for a three-position operation of the upper, middle, and lower sides of the second buffer.
According to a fourth aspect of the present invention, there is provided the conveying apparatus according to the first aspect , wherein the upper and lower two-stage plates are configured by stacking thin plates having the same shape vertically.
The invention described in claim 5 is a semiconductor manufacturing apparatus including the transfer device described in claim 1.

According to the first aspect of the present invention, since the second buffer capable of placing the substrate before processing and the substrate after processing is provided in the transfer chamber, the gate valve between the transfer chamber and the processing apparatus is opened, Even when the transfer robot replaces an unprocessed substrate and a processed substrate with respect to the processing apparatus, it is not necessary to open the gate valve between the load lock chamber and the transfer chamber, and the corrosive gas to the outside of the transfer apparatus can be removed . It is possible to prevent leakage and ensure safety. In addition, since the first buffer is placed on one substrate so that only the upper and lower positions are operated, the volume of the load lock chamber is reduced, and the time required for evacuation and return to the atmosphere can be shortened . Further, since the pump capacity is reduced by downsizing the load lock chamber, the cost can be reduced. In addition, since the transfer robot is configured with a single arm and a fork, the capacity of the transfer chamber can be reduced as compared with the use of a normal horizontal articulated robot having a plurality of arms. Small footprint can be realized. In addition, since the second buffer is configured to be positioned at the center of rotation of the single arm, the footprint of the second buffer is not required, and the substrate is replaced when the transfer robot replaces the substrate with respect to the processing chamber. Can improve the throughput.
According to the second aspect of the present invention, the first buffer mounted in the load lock chamber can be realized with a simple and low-cost mechanism.
According to the third aspect of the present invention, the second buffer mounted in the transfer chamber can be realized with a simple and low-cost mechanism.
According to the fourth aspect of the present invention, since two substrates can be buffered up and down with an area equivalent to one substrate, footprint reduction and throughput improvement can be realized simultaneously.
According to the invention described in claim 5, a semiconductor manufacturing apparatus having a small footprint can be realized.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a view showing an embodiment of a transfer apparatus according to the present invention, FIG. 1 (a) is a top view of the apparatus, and FIG. 1 (b) is a side view.
In FIG. 1, reference numeral 1 denotes a load lock chamber for carrying an unprocessed substrate from the outside of the apparatus and carrying out a processed substrate to the outside of the apparatus. The load lock chamber is repeatedly evacuated and returned to the atmosphere by a pump (not shown). Reference numeral 2 denotes a processing chamber for processing the substrate surface, and performs various processes depending on the manufacturing process. A transfer chamber 3 includes a transfer robot 7. Each of the load lock chamber 1 and the transfer chamber 3 includes a buffer 10 and a buffer 11 on which a substrate is placed.
Each part is partitioned by a partition valve, 4 is a partition valve that partitions the outside of the apparatus and the load lock chamber 1, 5 is a partition valve that partitions the load lock chamber 1 and the transfer chamber 3, and 6 is a transfer chamber 3 and a processing chamber. 2 is a gate valve that partitions the door 2 and opens and closes as necessary. Each gate valve opens and closes so that the inside of the transfer chamber 3 is always kept in a vacuum state.

  Further, since each part of the load lock chamber 1, the processing chamber 2, and the transfer chamber 3 is partitioned, even if the corrosive gas used in the processing chamber 2 leaks into the transfer chamber 3, the contamination immediately spreads to the outside of the apparatus. Can be prevented.

The transfer robot 7 is a horizontal multi-joint mechanism robot having a single arm 8, and a substrate is placed on a fork 9 at the tip of the arm and placed in the buffer 10 in the load lock chamber 1, the buffer 11 in the transfer chamber 3, and the processing chamber 2. The transfer operation is performed.
The transfer robot 7 may be a simple configuration having only a single arm 8 and a fork 9 having appropriate lengths, and can be operated independently. As a result, a low cost can be realized as compared to a configuration in which a plurality of arms each include a fork, which is frequently used in a conventional horizontal articulated mechanism.

The load lock chamber 1 includes a buffer 10 on which a single substrate can be mounted and operates only in two upper and lower positions. The purpose of the vertical movement of the buffer 10 is to realize substrate transfer without adding a vertical movement mechanism to the transfer robot 7.
Generally, in order to move the transfer robot up and down, a complicated mechanism and a large-capacity motor are required to move up and down all the mechanisms for turning the arm and fork, and a buffer that can move the substrate up and down is provided. Providing it is cheaper and the configuration is simpler.
In this embodiment, the mechanism 12 that moves the buffer 10 up and down is not a combination of a servo motor and a ball screw that are generally used, but a two-position air cylinder that is inexpensive and has a simple structure.

  Further, the load lock chamber needs to have a volume as small as possible. This is because the throughput is improved by saving time for evacuation and returning to the atmosphere by the pump. Here, since the buffer for one substrate is provided in the load lock chamber, it is not difficult to suppress the volume of the load lock chamber.

The plate of the buffer 11 in the transfer chamber 3 is a thin plate having the same shape, and two plates are arranged vertically. The center of the upper and lower two-stage plates on which the substrate is mounted is installed so as to be located within the operating range of the fork 9 of the transfer robot 7 and on the turning center of the arm 8. Each plate has a sufficient area for mounting the substrate, and as shown in FIG. 5, it has a shape that fits between the ends of the fork 9 divided into two forks.
The buffer 11 also moves up and down when transferring the substrate to and from the transfer robot 7. The mechanism for moving the buffer 11 up and down can be realized at low cost using an air cylinder, as with the buffer 10. However, since the air cylinder cannot control the subtle vertical movement speed, there is a demerit that the substrate is finely moved and dust is generated during the transfer of the substrate. In this embodiment, a mechanism using a servo motor and a ball screw is used. 13, the buffer 11 is moved up and down.

The operation of the transport device of the present invention will be described with reference to FIGS.
In the initial state, the gate valves 4, 5, and 6 are all closed, the load lock chamber 1 is in the same state as the atmosphere, and the processing chamber 2 and the transfer chamber 3 are in a vacuum state. Further, it is assumed that there is no processed substrate in the processing chamber 2.

(1) First, the gate valve 4 between the load lock chamber 1 and the outside of the apparatus is opened, and the unprocessed substrate 14 is placed in a predetermined place of the load lock chamber 1, that is, the buffer 10.
(2) The gate valve 4 is closed, the atmosphere in the load lock chamber 1 is exhausted to a predetermined pressure by a pump (not shown), and the same vacuum state as that of the transfer chamber 3 is obtained.
(3) The gate valve 5 between the load lock chamber 1 and the transfer chamber 3 is opened, and the transfer robot 7 extends the arm 8 and forks the unprocessed substrate 14 from the buffer 10 of the load lock chamber 1 as shown in FIG. Then, the arm 8 is contracted again and carried into the transfer chamber 3. When exchanging the substrate with the load lock chamber 1, the arm 8 is operated so that the fork 9 moves linearly. Thereafter, the gate valve 5 is closed again. Thereafter, the inside of the load lock chamber 1 is returned to the same state as the atmosphere outside the apparatus.
(4) In the transfer chamber 3, the transfer robot 7 turns the arm 8 as shown in FIGS. 3, 4, and 5 to transfer the unprocessed substrate 14 to the front of the process chamber 2. The gate valve 6 between the processing chamber 2 and the transfer chamber 3 is opened, and the transfer robot 7 extends the arm 8 and carries the unprocessed substrate 14 on the fork 9 into the process chamber 2 as shown in FIG. After carrying in the substrate, the transfer robot 7 immediately contracts the arm 8 to return the fork 9 into the transfer chamber 3 and closes the gate valve 6. When exchanging the substrate with the processing chamber 2, the arm 8 is operated so that the fork 9 moves linearly.
(5) While the processing is being performed in the processing chamber 2, the transfer robot 7 transfers another unprocessed substrate 14 from the load lock chamber 1 to the transfer chamber 3 according to the sequence of (1) to (3). And carry. Thereafter, the unprocessed substrate 14 is placed on the upper stage of the buffer 11 in the transfer chamber 3. The transfer of the substrate between the transfer robot 7 and the buffer 11 will be described later.
(6) When the processing in the processing chamber 2 is completed, the gate valve 6 is opened, and the transfer robot 7 operates the arm 8 again so that the fork 9 moves linearly as shown in FIG. The substrate 15 is taken out. Then, as shown in FIG. 5, the arm 8 turns to place the processed substrate 15 on the lower stage of the buffer 11. Here, in (5) and (6), the unprocessed substrate 14 is placed on the upper stage of the buffer 11, and the processed substrate 15 is placed on the lower stage of the buffer 11. Depending on the processing contents in the processing chamber 2, the processed substrate 15 may be contaminated. If the processed substrate 15 is mounted on the upper stage and the unprocessed substrate 14 is mounted on the lower stage, the processed substrate 15 is processed. This is because the dust from 15 may fall and adhere to the untreated substrate 14. Further, in preparation for the case where corrosive gas is used in the processing chamber 2, the surface of the arm 8, the fork 9, and the buffer 11 of the transfer robot 7 is subjected to corrosion reduction processing.
(7) Next, the transfer robot 7 places the upper unprocessed substrate 14 on the buffer 11 on the fork 9 and transfers it into the processing chamber 2 as shown in FIG. Thereafter, the gate valve 6 is closed and processing is performed in the processing chamber 2. During (6) and (7), the inside of the load lock chamber 1 is again evacuated by a pump.
(8) While the processing is being performed in the processing chamber 2, the transfer robot 7 takes out the processed substrate 15 from the lower stage of the buffer 11, and after the arm 8 turns as shown in FIGS. Then, the processed substrate 15 is placed on the buffer 10 in the load lock chamber 1 as shown in FIG.
(9) When the transfer robot 7 retracts the arm 8 and returns to the transfer chamber 3, the gate valve 5 is closed and the load lock chamber 1 is brought into the same state as the atmosphere outside the apparatus by a pump, and then the gate valve 4 is opened and processed. The finished substrate 15 is carried out to the outside.
The above operation is repeated, and the substrates are transferred one by one and processed.
In addition, in order to explain the operation trajectory of the transfer robot 7, the buffer 11 in the transfer chamber 3 is omitted in FIGS.

  As described above, a single-arm transfer robot 7 that can independently drive the arm 8 and the fork 9 is adopted, and a small movement locus that combines a linear transfer section and a non-linear transfer section for linearly transferring a substrate. The transfer robot 7 is arranged at an appropriate position in the transfer chamber 3 so that the transfer can be carried out by the above. The buffer 11 is installed at a position where the substrate can be transferred at the center of the arm rotation of the transfer robot 7. As a result, the capacity of the transfer chamber 3 is reduced and a small footprint is realized.

  Next, the manner in which the transfer robot 7 and the buffer 11 exchange the substrate will be described with reference to FIG. As shown in FIG. 7, the transfer of the substrate is realized by enabling the two-stage buffer 11 to move to the fork 9 of the transfer robot 7 to a total of three positions including the upper and lower ends and the intermediate point.

FIG. 7A shows a state after the unprocessed substrate 14 placed on the upper stage of the buffer 11 is transferred to the fork 9 as the buffer 11 moves to the lower end.
Further, when the buffer 11 moves upward from this state, the unprocessed substrate 14 placed on the fork 9 can be transferred to the upper stage of the buffer 11.

FIG. 7B shows a state after the unprocessed substrate 14 placed on the fork 9 is transferred to the upper stage of the buffer 11 as the buffer 11 moves upward.
Further, by moving the buffer 11 downward from this state, the unprocessed substrate 14 placed on the upper stage of the buffer 11 can be transferred to the fork 9.

FIG. 7C shows a state after the processed substrate 15 placed on the fork 9 is transferred to the lower stage of the buffer 11 as the buffer 11 moves to the upper end.
Further, by moving the buffer 11 downward from this state, the processed substrate 15 placed on the lower stage of the buffer 11 can be transferred to the fork 9.

FIG. 7D shows a state after the processed substrate 15 placed on the lower stage of the buffer 11 is transferred to the fork 9 as the buffer 11 moves downward.
Further, by moving the buffer 11 upward from this state, the processed substrate 15 placed on the fork 9 can be transferred to the lower stage of the buffer 11.

Among the above states, the vertical positions of the buffers 11 in FIGS. 7B and 7D may be the same. That is, the buffer 11 only needs to be able to operate at three positions.
In this embodiment, a mechanism combining a servo motor and a ball screw is used as described above, but an air cylinder capable of three-position operation may be used.
Further, the operation mechanism 12 of the buffer 10 in the load lock chamber 1 may be driven by a servo motor and a ball screw.

The present invention can simultaneously reduce footprint and improve throughput by providing a vertically moving buffer in the transfer chamber, and can be widely applied to single wafer type semiconductor manufacturing apparatuses.

The figure which shows the conveying apparatus of this invention The top view which shows the operation | movement of the arm of a conveyance robot in the conveyance apparatus of this invention, and the locus | trajectory of a board | substrate. The top view which shows the operation | movement of the arm of a conveyance robot in the conveyance apparatus of this invention, and the locus | trajectory of a board | substrate. The top view which shows the operation | movement of the arm of a conveyance robot in the conveyance apparatus of this invention, and the locus | trajectory of a board | substrate. The top view which shows the operation | movement of the arm of a conveyance robot in the conveyance apparatus of this invention, and the locus | trajectory of a board | substrate. The top view which shows the operation | movement of the arm of a conveyance robot in the conveyance apparatus of this invention, and the locus | trajectory of a board | substrate. The side view explaining transfer of the board | substrate with the transfer robot and buffer in the transfer apparatus of this invention Diagram showing conventional semiconductor manufacturing equipment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Load lock chamber 2 Processing chamber 3 Transfer chamber 4, 5, 6 Gate valve 7 Transfer robot 8 Arm 9 Fork 10, 11 Buffer 12, 13 Buffer operation mechanism 14 Unprocessed substrate 15 Processed substrate 101 Reactor 102 Load lock chamber 103 Transfer Arm 104, 105 Support means 106 Cylinder 107 Susceptor drive motor 108 Cylinder 109 Rotary actuator 110 Bellows 111 Rotary actuator 112 Semiconductor wafer 113 Gate valve 114 Susceptor 115 Wafer lift pin 116 O-ring 117 Shaft means 118 Dry pump 119 Shower head 120 Flapper valve

Claims (5)

In a transfer apparatus that carries in and out a substrate to be processed with respect to a single-wafer semiconductor processing apparatus that performs processing in a vacuum environment ,
The transfer device is
The substrate placed on the first buffer when the substrate is provided with a first buffer for placing one of the substrates and performing upper and lower two-position operations, and repeatedly performing vacuum or atmospheric conditions. A load lock chamber that communicates with the outside of the transfer device;
A transfer chamber connected between the load lock chamber and the processing chamber so that the load lock chamber and the processing apparatus are arranged in a straight line, and kept in a vacuum state at all times;
A horizontal articulated robot that is provided in the transfer chamber and transfers the substrate to the load lock chamber or the processing apparatus in a vacuum state;
A second buffer provided in the transfer chamber and capable of transferring the substrate with the horizontal articulated robot;
The horizontal articulated robot is composed of one single arm and the fork that rotates at the tip of the single arm independently of the single arm,
The second buffer includes upper and lower two-stage plates composed of first and second plates, and the substrate is placed on each of the first and second plates by performing upper, middle, and lower three-position operations. Configured to be able to be placed,
The transport apparatus according to claim 1, wherein the second buffer is installed so that a center position on which the substrate of the upper and lower two-stage plates is placed is positioned at a rotation center of the single arm . The conveying apparatus according to claim 1 , wherein an air cylinder that performs a two-position operation is used as a mechanism for the two-position operation above and below the first buffer. 2. The conveying apparatus according to claim 1 , wherein an air cylinder that performs a three-position operation is used as a mechanism for an upper, middle, and lower three-position operation of the second buffer. The transport apparatus according to claim 1, wherein the upper and lower two-stage plates are configured by vertically stacking thin plates having the same shape . A semiconductor manufacturing apparatus comprising the transfer apparatus according to claim 1 .

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