Wafer conveying system

Abstract

The invention relates to the technical field of semiconductor manufacturing, and provides a wafer transfer system, which comprises a top interlocking cavity, a top interlocking cavity and a bottom interlocking cavity, the bottom interlocking cavity is located below the top interlocking cavity, the top interlocking cavity and the bottom interlocking cavity are provided with transmission valves, and when the transmission valves are opened, a plurality of wafers are stored in or taken out of the top interlocking cavity and the bottom interlocking cavity. According to the invention, the transmission efficiency of the wafer can be obviously improved, and the highest transmission efficiency of about 320 wph can be realized. And through cooperative work of the gas diffuser and the cooling disc, rapid and uniform cooling of the wafer can be realized, and overheating of the wafer is effectively avoided.

Description

Technical Field

[0001] The present invention generally relates to the field of semiconductor manufacturing technology. In particular, the present invention relates to a wafer transfer system. Background Art

[0002] In the semiconductor manufacturing process, wafers need to be transferred between different process chambers. The traditional vacuum transfer method is inefficient and difficult to meet the needs of high-speed production.

[0003] Figure 1A-Figure 1C FIG. 2 shows a schematic diagram of the structure of a wafer transfer system in the prior art. Figure 1A As shown in the figure, the multi-wafer interlock chamber (Loadlock) takes a lot of time to complete the vacuuming of the chamber due to the large volume of the chamber. When the wafer in one chamber completes the process, the other chamber is usually not completely vacuumed. In addition, the multi-wafer interlock chamber also has problems such as being unable to heat or cool each wafer in the chamber, and the transmission speed of the vacuum robot has a bottleneck (the maximum speed is about 120-130wph (wafer per hour)).

[0004] Figure 1B The system shown is Figure 1A Improvements to the system shown, such as Figure 1B As shown, each single-chip interlocking chamber only transfers one wafer, and the interlocking chamber is provided with two layers, and both sides of each interlocking chamber can be transferred, thereby speeding up the transfer speed of the wafer. During the transfer process, the upper interlocking chamber takes out the wafer from the process chamber and returns it to the front-end equipment module (EFEM), and the lower layer takes out the wafer from the EFEM and enters the interlocking chamber and returns it to the EFEM. The transfer process of the upper or lower layer can also be interchanged. In addition, the interlocking chamber can also have two stations for storing wafers. The robot in the interlocking chamber puts the wafer that has been processed taken out of the process chamber into the first station, and takes out the wafer to be processed from the second station to complete the wafer transfer. Correspondingly, the process chamber also has two stations, and the robot puts the wafer to be processed into the first station, and takes out the wafer that has been processed from the second station to complete the wafer transfer.

[0005] Figure 1C The system described is Figure 1B Improvements to the system shown, such as Figure 1C As shown, a cooling water tray or heater is further arranged in the interlock chamber. The two interlock chambers on the left and right sides of the system can simultaneously transfer two wafers, and the transfer speed of the robot can be increased to about 240-260wph. However, in this system, when the process processing time of the process chamber is less than the wafer exchange and valve switch exhaust time of the interlock chamber, the interlock chamber will still become a bottleneck affecting the speed of wafer shuttle.

[0006] In general, the existing multi-chip interlocking cavity has problems such as the cavity is too large, the air extraction time is long, and each piece cannot be heated or cooled. Although the single-chip interlocking cavity improves the transmission efficiency, the transmission speed of the robot still has a bottleneck. Summary of the invention

[0007] In order to at least partially solve the above problems in the prior art, the present invention provides a wafer transfer system, comprising:

[0008] Top interlock cavity; and

[0009] The bottom interlock chamber is located below the top interlock chamber, and the top interlock chamber and the bottom interlock chamber are provided with transfer valves, wherein when the transfer valves are opened, multiple wafers are stored or taken out from the top interlock chamber and the bottom interlock chamber.

[0010] In one embodiment of the present invention, it is provided that the top interlock chamber and the bottom interlock chamber are in communication with an atmosphere side and a vacuum side, wherein the transfer valve is located at the atmosphere side and the vacuum side of the top interlock chamber and the bottom interlock chamber.

[0011] In one embodiment of the present invention, the top interlocking cavity and / or the bottom interlocking cavity comprises a first side cavity and a second side cavity, the first side cavity and the second side cavity are independent of each other, and transfer valves are provided on both sides of the first side cavity and the second side cavity.

[0012] In one embodiment of the present invention, it is provided that the wafer transfer system further comprises:

[0013] An atmospheric side robot is configured to transfer wafers between the wafer cassette and the top interlock chamber and the bottom interlock chamber.

[0014] In one embodiment of the present invention, it is provided that the atmosphere-side manipulator is located in a front-end equipment module.

[0015] In one embodiment of the present invention, it is provided that the atmospheric measurement manipulator has a plurality of end effectors.

[0016] In one embodiment of the present invention, it is provided that the end effector comprises a gripper or a vacuum suction cup.

[0017] In one embodiment of the present invention, it is provided that the wafer transfer system further comprises:

[0018] A vacuum side robot is configured to transfer wafers between the transfer chamber and the top interlock chamber and the bottom interlock chamber.

[0019] In one embodiment of the present invention, it is provided that the vacuum side robot comprises a first layer end effector and a second layer end effector, wherein the first layer end effector and the second layer end effector are located at different heights.

[0020] In one embodiment of the present invention, it is provided that the actions of the first layer end effector and the second layer end effector are independent of each other; or

[0021] The first layer end effector and the second layer end effector have the same degree of freedom of movement, but have independent movement directions, such as moving towards or away from each other.

[0022] In one embodiment of the present invention, it is provided that the first layer end effector and the second layer end effector are configured to move in the Z-axis direction to pick up and place the wafer located at the top of the top interlocking cavity and the wafer located at the bottom of the bottom interlocking cavity.

[0023] In one embodiment of the present invention, it is provided that the top interlocking chamber and the bottom interlocking chamber are alternately connected to the atmosphere side and the vacuum side.

[0024] In one embodiment of the present invention, when the top interlock chamber or the bottom interlock chamber is connected to the atmosphere, the system is configured to perform the following actions:

[0025] Open the transfer valve on the atmosphere side;

[0026] The atmosphere-side robot takes out a plurality of processed wafers from the top interlock chamber or the bottom interlock chamber and places them into a wafer box, and takes out a plurality of unprocessed wafers from the wafer box and places them into the top interlock chamber or the bottom interlock chamber; and

[0027] Close the transfer valve on the atmosphere side.

[0028] In one embodiment of the present invention, when the top interlock chamber or the bottom interlock chamber is connected to the vacuum side, the system is configured to perform the following actions:

[0029] Open the transfer valve on the vacuum side;

[0030] The first layer end effector of the vacuum side robot is set to an unloaded state, and the second layer end effector is loaded with processed wafers;

[0031] The first-layer end effector enters the top interlock cavity or the bottom interlock cavity to take out the unprocessed wafer at the first position, and the second-layer end effector puts the processed wafer into the first position;

[0032] Two unprocessed wafers are fed into a process chamber, and two processed wafers are taken out of the process chamber;

[0033] The vacuum side robot repeatedly repeats the above actions until the unprocessed wafer in the top interlock chamber or the bottom interlock chamber is replaced with the processed wafer; and

[0034] Close the transfer valve on the vacuum side.

[0035] In one embodiment of the present invention, it is provided that the wafer transfer system further comprises:

[0036] A diffuser is located at a side of the top interlock chamber and / or the bottom interlock chamber, wherein cooling gas flows out of the diffuser and flows over the wafer surface in a direction parallel to the wafer surface.

[0037] In one embodiment of the present invention, it is provided that the diffusers located in the first side cavity and the diffusers located in the second side cavity share an exhaust passage.

[0038] In one embodiment of the present invention, it is provided that the cooling gas includes nitrogen or clean dry air.

[0039] In one embodiment of the invention, it is provided that the diffuser has a plurality of diffuser inlets.

[0040] In one embodiment of the present invention, it is provided that the wafer transfer system further comprises:

[0041] A cooling water channel is located at the bottom of the top interlocking cavity and / or the bottom interlocking cavity.

[0042] In one embodiment of the present invention, it is provided that the material of the cooling water channel includes aluminum.

[0043] The present invention has at least the following beneficial effects: The present invention proposes a high-speed vacuum wafer transmission system, which can significantly improve the transmission efficiency of wafers, and can achieve a maximum transmission efficiency of about 320wph. At the same time, through the coordinated work of the gas diffuser and the cooling plate, the wafer can be cooled quickly and evenly, effectively avoiding overheating of the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] To further illustrate the advantages and features of various embodiments of the present invention, a more detailed description of various embodiments of the present invention will be presented with reference to the accompanying drawings. It will be understood that these drawings only depict typical embodiments of the present invention and are therefore not to be considered as limiting the scope thereof. In the accompanying drawings, for clarity, identical or corresponding parts will be represented by identical or similar reference numerals.

[0045] Figure 1A-Figure 1C A schematic structural diagram of a wafer transfer system in the prior art is shown.

[0046] Figure 2A schematic structural diagram of a wafer transfer system according to an embodiment of the present invention is shown.

[0047] Figure 3A-3B A schematic diagram of a wafer transfer process of a wafer transfer system according to an embodiment of the present invention is shown.

[0048] Figure 4A and Figure 4B A schematic diagram of the internal structure of an interlocking cavity of a wafer transfer system according to an embodiment of the present invention is shown.

[0049] Figure 5A-5D A schematic diagram of the internal structure of an interlocking cavity of a wafer transfer system according to another embodiment of the present invention is shown.

[0050] Figure 6A-6D A schematic diagram of airflow inside an interlocking chamber of a wafer transfer system according to another embodiment of the present invention is shown.

[0051] Figure 7 A bottom schematic diagram of an interlocking chamber of a wafer transfer system according to another embodiment of the present invention is shown. DETAILED DESCRIPTION

[0052] It should be noted that the components in the figures may be shown exaggeratedly for the sake of illustration and are not necessarily true to scale. In the figures, identical or functionally identical components are provided with the same reference numerals.

[0053] In the present invention, unless otherwise specified, "arranged on...", "arranged above..." and "arranged above..." do not exclude the existence of an intermediate between the two. In addition, "arranged on or above..." merely indicates the relative positional relationship between two components, and in certain cases, such as after reversing the product direction, it can also be converted into "arranged below or below...", and vice versa.

[0054] In the present invention, each embodiment is only intended to illustrate the aspects of the present invention and should not be construed as limiting.

[0055] In the present invention, unless otherwise specified, the quantifiers "a", "an" and "an" do not exclude the presence of a plurality of elements.

[0056] It should also be noted that in the embodiments of the present invention, for the sake of clarity and simplicity, only a portion of the parts or components may be shown, but those of ordinary skill in the art will understand that under the teachings of the present invention, the required parts or components may be added according to the needs of the specific scenario. In addition, unless otherwise specified, the features in different embodiments of the present invention may be combined with each other. For example, a feature in the second embodiment may be used to replace a corresponding or functionally identical or similar feature in the first embodiment, and the resulting embodiment also falls within the disclosure scope or recorded scope of the present application.

[0057] It should also be noted that within the scope of the present invention, the terms "same", "equal", "equal to" and the like do not mean that the values ​​of the two are absolutely equal, but allow a certain reasonable error, that is, the terms also cover "substantially the same", "substantially equal", "substantially equal to". By analogy, in the present invention, the terms "perpendicular to", "parallel to" and the like indicating directions also cover the meanings of "substantially perpendicular to" and "substantially parallel to".

[0058] In the present application, the term "configuration" refers to the setting of the shape, structure, material and / or function of the target object to achieve the desired technical effect, wherein "configuration" includes a variety of alternative technical means for achieving the technical effect, which become obvious under the teaching of the present application.

[0059] In addition, the numbering of the steps of the methods of the present invention does not limit the execution order of the method steps. Unless otherwise specified, the method steps can be executed in different orders.

[0060] The present invention will be further described below in conjunction with specific embodiments with reference to the accompanying drawings.

[0061] Figure 2 FIG. 2 shows a schematic diagram of the structure of a wafer transfer system according to an embodiment of the present invention. Figure 2 As shown, the system includes a top interlock chamber 210 , a bottom interlock chamber 220 , an atmosphere-side robot 230 , a vacuum-side robot 240 , and a transfer valve 250 .

[0062] The bottom interlock chamber 220 is located below the top interlock chamber 210. In some embodiments, the atmosphere side and the vacuum side of the top interlock chamber 210 and the bottom interlock chamber 220 are directly connected, and the atmosphere side and the vacuum side of the top interlock chamber 210 and the bottom interlock chamber 220 are provided with an air transfer valve 250, and the transfer valve 250 is used to isolate the interlock chamber from the vacuum or the atmosphere.

[0063] In some embodiments, the top interlock chamber 210 or the bottom interlock chamber 220 has a first side chamber and a second side chamber, the first side chamber and the second side chamber are independent of each other, and both sides of the first side chamber and the second side chamber have a transfer valve 250. In some embodiments, multiple wafers in the interlock chamber are taken out or put in at the same time.

[0064] The atmospheric side robot 230 is located in the front-end equipment module, and is used to transfer wafers between the wafer box (FOUP) and the top interlock chamber 210 and the bottom interlock chamber 220. In some embodiments, the atmospheric side robot 230 has multiple end effectors, and multiple wafers (preferably 2-5 wafers) can be loaded at one time for transfer through the atmospheric side robot 230. In some embodiments, the end effector is a gripper or a vacuum chuck to achieve stable gripping of the wafer during high-speed transfer.

[0065] The vacuum side robot 240 is used to transfer wafers between the transfer chamber and the top interlock chamber 210 and the bottom interlock chamber 220. In some embodiments, the vacuum side robot 240 has a first layer end effector and a second layer end effector located at different heights, and the first layer end effector and the second layer end effector move independently of each other. In some embodiments, the first layer end effector and the second layer end effector have the same degree of freedom, but have independent movement directions, such as moving toward or away from each other, that is, when the first layer end effector moves forward, the second layer end effector moves backward, or when the first layer end effector moves backward, the second layer end effector moves forward. In some embodiments, the first layer end effector and the second layer end effector can move in the Z-axis direction, so that the vacuum side robot 240 can pick up and place the wafer located at the top of the top interlock chamber 210 and the wafer located at the bottom of the bottom interlock chamber 220.

[0066] Figure 3A-3B FIG. 2 shows a schematic diagram of a wafer transfer process of a wafer transfer system according to an embodiment of the present invention. Figure 3A and Figure 3B As shown, the top interlocking chamber 210 and the bottom interlocking chamber 220 are alternately connected to the vacuum side or the atmosphere side. Figure 3A Take this as an example for specific explanation.

[0067] like Figure 3AAs shown, the top interlock chamber 210 is connected to the vacuum side, and the transmission valve 250 on the vacuum side is opened. The first layer end effector of the vacuum side manipulator 240 is in an unloaded state, and the second layer end effector is loaded with a processed wafer taken out from the process chamber. The first layer end effector enters the top interlock chamber 210 to take out the unprocessed wafer at the first position, and the second layer end effector puts the processed wafer into the first position. Further, the vacuum side manipulator 240 sends two unprocessed wafers into the process chamber and takes out two processed wafers from the process chamber. Repeat the above actions repeatedly until the unprocessed wafers at N positions in the top interlock chamber 210 are exchanged for processed wafers, and the transmission valve 250 on the vacuum side is closed. In the prior art, when N=2-5, and the working time of the process chamber is short, too many opening and closing times of the transmission valve 250 on the vacuum side will affect the transmission efficiency. Compared with the prior art, the opening and closing time of the transfer valve 250 is greatly reduced during the vacuum side wafer transfer process of the wafer transfer system according to the present application. The opening and closing time of the vacuum valve can be reduced by N-1 times for every N wafers transferred, which can improve the transfer efficiency by about 10%-20%, that is, the maximum transfer efficiency of about 320wph can be achieved.

[0068] When the top interlock chamber 210 is connected to the vacuum side, the bottom interlock chamber 220 is connected to the atmosphere side, and the transfer valve 250 on the atmosphere side is opened. The atmosphere side manipulator 230 takes out N processed wafers from the bottom interlock chamber 220 and puts them into the wafer box, and takes out N unprocessed wafers from the wafer box and puts them into the bottom interlock chamber 220, and closes the transfer valve 250 on the atmosphere side. Since the atmosphere side manipulator 230 can take and place N wafers at a time, and the end effector is a gripper or a vacuum chuck, the movement speed of the atmosphere side manipulator 230 can be faster than that of the vacuum side manipulator 240, so that the wafer transfer speed on the atmosphere side is much higher than that on the vacuum side.

[0069] Then, the top interlock chamber 210 and the bottom interlock chamber 220 are alternately connected to the vacuum side or the atmosphere side, and the cycle is repeated to achieve a high-speed wafer transfer of about 320 wph.

[0070] Generally speaking, the process time in the process chamber is short and the temperature is high (eg, 250-300° C.), which does not affect the existing wafer transfer system. Figure 1A The system shown has a natural cooling process. When the first wafer enters the interlocking chamber, it needs to wait for the subsequent multiple wafer processes to be completed. When the interlocking chamber is connected to the atmosphere, the first wafer has completed natural cooling. Subsequent wafers only need to be transported according to the first-in-first-out strategy, which can also ensure that they have completed natural cooling during transportation. Figure 1B-C described in the system can achieve rapid cooling of the wafers through the cooling plate built into the interlocking cavity. In the present application, due to the fast transportation speed of the wafers, the natural cooling time is insufficient, and the cooling plate can only cool the wafers at the bottom, and there is a risk that the wafers at other positions cannot be cooled in time. Therefore, in some embodiments of the present application, the internal structure of the interlocking cavity is further improved.

[0071] Figure 4A and Figure 4B FIG. 2 shows a schematic diagram of the internal structure of an interlocking cavity of a wafer transfer system according to an embodiment of the present invention. Figure 4A and Figure 4B As shown, in the conventional design, the diffuser 410 is usually located at the top of the interlocking chamber, and its function is to quickly fill the interlocking chamber with gas instead of cooling the wafer. Therefore, the airflow from the diffuser 410 will be blocked by the wafer at the top, so that the wafer at the middle position cannot be cooled by the high-speed airflow.

[0072] Figure 5A-5D A schematic diagram of the internal structure of an interlocking cavity of a wafer transfer system according to another embodiment of the present invention is shown. Figure 6A-6D FIG. 2 shows a schematic diagram of the airflow inside the interlocking chamber of a wafer transfer system according to another embodiment of the present invention. Figure 5A-5D , Figure 6A-6D As shown, the diffuser 410 is located on the side of the interlocking cavity, so that the cooling gas flows out from the diffuser inlet 411 in a direction parallel to the wafer surface and then flows through the wafer surface to cool the wafer. Figure 5A As shown, each cavity may have two diffusers 410. Figure 5B As shown, the first side cavity 211 and the second side cavity 212 of the top interlock cavity 210 may share the exhaust passage 213, or as shown in FIG. Figure 5C As shown, the first side cavity 221 and the second side cavity 222 of the bottom interlocking cavity 220 may share an exhaust passage 223 .

[0073] In some embodiments, the cooling gas is nitrogen (N 2 ) or clean dry air (CDA).

[0074] In some embodiments, the diffuser 410 has multiple diffuser inlets 411 to reduce the lateral temperature gradient. This is because the cooling gas needs a higher flow rate to achieve a sufficient cooling rate for the wafer (for example, greater than 5 slm). Fig. 6A The solid line in the middle) is located Fig. 6AThe flow rate of the cooling airflow at the middle dotted line is small, resulting in insufficient cooling in these areas. In addition, in the upstream and downstream of the solid line area, due to the temperature rise of the airflow, the cooling effect of the downstream will be deteriorated, and a large temperature gradient (for example, 20-50°C) will be generated in the direction of the solid line, which will cause the wafer to be heated unevenly and break. The risk. By setting a plurality of diffuser inlets 411 and / or exhaust outlets, the flow field of the cooling airflow can be effectively uniformed, so that the wafer is evenly cooled and has a very small temperature gradient. In addition, the provision of multiple diffuser inlets 411 can also reduce the impact of the cooling airflow on the wafer, and prevent the displacement of the wafer from affecting the wafer transmission.

[0075] Figure 7 FIG. 2 shows a bottom schematic diagram of an interlocking chamber of a wafer transfer system according to another embodiment of the present invention. Figure 7 The bottom of the interlocking cavity is provided with a cooling water channel 710, which can form a cooling plate at the bottom of the interlocking cavity, thereby cooling the wafer at the bottom of the interlocking cavity. The cooling water channel 710 and the diffuser 410 can form a mixed heat exchange, thereby improving the cooling efficiency of the wafer inside the interlocking cavity. In some embodiments, the material of the cooling water channel 710 is aluminum, and the thermal conductivity is 100.

[0076] Although various embodiments of the present invention are described above, it should be understood that they are presented as examples only and not as limitations. It is obvious to those skilled in the relevant art that various combinations, modifications and changes can be made thereto without departing from the spirit and scope of the present invention. Therefore, the breadth and scope of the present invention disclosed herein should not be limited by the exemplary embodiments disclosed above, but should only be defined according to the attached claims and their equivalents.

Claims

1. A wafer transfer system, characterized in that: include: Top interlocking cavity; A bottom interlock chamber, which is located below the top interlock chamber, wherein the top interlock chamber and the bottom interlock chamber have transfer valves, wherein a plurality of wafers are stored or taken out from the top interlock chamber and the bottom interlock chamber when the transfer valves are opened; An atmospheric side robot configured to transfer wafers between a wafer box and a top interlock cavity and a bottom interlock cavity, the atmospheric side robot being located in a front-end equipment module, the atmospheric side robot having a plurality of end effectors, the end effectors including grippers or vacuum chucks; as well as A vacuum side robot, which is configured to transfer wafers between a transfer chamber and the top interlock chamber and the bottom interlock chamber, the vacuum side robot having a first layer end effector and a second layer end effector, wherein the first layer end effector and the second layer end effector are located at different heights, and the movements of the first layer end effector and the second layer end effector are independent of each other; or the first layer end effector and the second layer end effector have the same degree of freedom of movement, but have independent movement directions, and the first layer end effector and the second layer end effector are configured to move in a Z-axis direction to pick up and place wafers located at the top of the top interlock chamber and wafers located at the bottom of the bottom interlock chamber, wherein the top interlock chamber and the bottom interlock chamber are in communication with an atmosphere side and a vacuum side, wherein the transfer valve is located at the atmosphere side and the vacuum side of the top interlock chamber and the bottom interlock chamber, The top interlocking cavity and / or the bottom interlocking cavity comprises a first side cavity and a second side cavity, the first side cavity and the second side cavity are independent of each other, and both sides of the first side cavity and the second side cavity are provided with transfer valves.

2. The wafer transfer system according to claim 1, characterized in that: The top interlocking chamber and the bottom interlocking chamber are alternately communicated with the atmosphere side and the vacuum side.

3. The wafer transfer system according to claim 1, characterized in that: When the top interlock chamber or the bottom interlock chamber is connected to the atmosphere, the system is configured to perform the following actions Open the transfer valve on the atmosphere side; The atmospheric side robot takes out a plurality of processed wafers from the top interlock chamber or the bottom interlock chamber and puts them into a wafer box, and takes out a plurality of unprocessed wafers from the wafer box and puts them into the top interlock chamber or the bottom interlock chamber; as well as Close the transfer valve on the atmosphere side.

4. The wafer transfer system according to claim 1, characterized in that: When the top interlock chamber or the bottom interlock chamber is connected to the vacuum side, the system is configured to perform the following actions: Open the transfer valve on the vacuum side; The first layer end effector of the vacuum side robot is set to an unloaded state, and the second layer end effector is loaded with processed wafers; The first-layer end effector enters the top interlock cavity or the bottom interlock cavity to take out the unprocessed wafer at the first position, and the second-layer end effector puts the processed wafer into the first position; Two unprocessed wafers are fed into a process chamber, and two processed wafers are taken out of the process chamber; The vacuum side robot repeatedly repeats the above actions until the unprocessed wafer in the top interlock chamber or the bottom interlock chamber is replaced with the processed wafer; as well as Close the transfer valve on the vacuum side.

5. The wafer transfer system according to claim 1, characterized in that: Also includes: A diffuser is located at a side of the top interlock chamber and / or the bottom interlock chamber, wherein cooling gas flows out of the diffuser and flows over the wafer surface in a direction parallel to the wafer surface.

6. The wafer transfer system according to claim 5, characterized in that: The diffusers located in the first side cavity and the second side cavity share an exhaust passage.

7. The wafer transfer system according to claim 5, characterized in that: The cooling gas includes nitrogen or clean dry air.

8. The wafer transfer system according to claim 5, characterized in that: The diffuser has a plurality of diffuser inlets.

9. The wafer transfer system according to claim 1, characterized in that: Also includes: A cooling water channel is located at the bottom of the top interlocking cavity and / or the bottom interlocking cavity.

10. The wafer transfer system according to claim 9, characterized in that: The material of the cooling water channel includes aluminum.

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