Substrate processing apparatus, substrate transport method

Abstract

To provide a substrate treatment apparatus and a substrate transfer method which are capable of increasing the throughput.SOLUTION: The substrate treatment apparatus comprises: a first load lock chamber having a plurality of wafer housing slots; a second load lock chamber having a plurality of wafer housing slots; and a controller including a processor and a memory configured to cause the processor to execute a program stored in the memory, or to perform a treatment with dedicated circuitry to determine whether predetermined wafer transfer conditions are satisfied, and to issue, to a wafer-moving device, a command to move a wafer between the first load lock chamber and the second load lock chamber when the wafer transfer conditions are satisfied.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a substrate processing apparatus and a substrate transfer method.

Background Art

[0002] For example, a substrate processing apparatus that processes a substrate in a low-pressure space such as a vacuum includes a plurality of load lock chambers. The load lock chamber is provided to prevent particles, water vapor, and contaminants from entering the process chamber.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to one example, the inability to load a wafer into the load lock chamber even though there is an empty slot in the load lock chamber, or the inability to promptly remove a processed wafer from the load lock chamber hinders the improvement of throughput.

[0005] The present disclosure has been made to solve the above-described problems, and an object thereof is to provide a substrate processing apparatus and a substrate transfer method capable of increasing throughput.

Means for Solving the Problems

[0006] The substrate processing apparatus according to this disclosure comprises: a plurality of load ports; a front-end module adjacent to the plurality of load ports; a first load lock chamber adjacent to the front-end module and having a plurality of wafer storage slots; a second load lock chamber adjacent to the front-end module and having a plurality of wafer storage slots; a wafer handling chamber adjacent to the first load lock chamber and the second load lock chamber; a first wafer transfer device located within the front-end module; a second wafer transfer device located within the wafer handling chamber; and a controller having a processor and memory, which determines whether predetermined wafer transfer conditions are met by executing a program stored in the memory with the processor or by processing with a dedicated circuit, and if the wafer transfer conditions are met, issues a command to the wafer transfer device to move the wafer between the first load lock chamber and the second load lock chamber. The wafer transport conditions are that there are wafers in the first load lock chamber and the second load lock chamber that have not yet been processed, and that there is a wafer to be transported to the first load lock chamber or the second load lock chamber in one of the load ports. The command causes the wafer moving device to operate so that there is no wafer in either the first load lock chamber or the second load lock chamber. .

[0007] Other features of this disclosure are outlined below. [Effects of the Invention]

[0008] This allows for faster transport of substrates in substrate processing equipment. [Brief explanation of the drawing]

[0009] [Figure 1] This figure shows an example of the configuration of a substrate processing apparatus. [Figure 2] This is a cross-sectional view of LLC 1 and its vicinity. [Figure 3] This figure shows an example of an execution flowchart for FLEX-LL. [Figure 4] This figure shows a specific example of FLEX-LL. [Figure 5] This figure shows a specific example of FLEX-LL. [Figure 6] This figure shows another specific example of FLEX-LL. [Figure 7] This figure shows another specific example of FLEX-LL. [Figure 8] This figure shows another specific example of FLEX-LL. [Figure 9] This is a functional block diagram of the controller. [Figure 10] Figure 10A shows an example of a controller configuration. Figure 10B shows an example of a controller configuration when the processing circuit is a CPU. [Figure 11] This figure shows an example of the configuration of a wafer moving device. [Figure 12] This figure shows an example configuration of a wafer moving device in a different case. [Figure 13] This diagram illustrates how wafers are moved using a wafer moving device. [Modes for carrying out the invention]

[0010] The substrate processing apparatus and substrate transport method will be described with reference to the drawings. The same or corresponding components are denoted by the same reference numerals, and repetition of descriptions may be omitted.

[0011] Embodiment. Figure 1 shows an example configuration of a substrate processing apparatus 10. This substrate processing apparatus is equipped with multiple load ports. In the example in Figure 1, load ports 12, 14, and 16 are provided. Here, the number of load ports is set to three, but it may also be two or four or more. A front-end module 18 is provided adjacent to the multiple load ports 12, 14, and 16. The front-end module 18 has, for example, a Fan Filter Unit (FFU) and is provided for transporting substrates under atmospheric pressure. A first wafer transport device 19 is located inside the front-end module 18. In one example, the first wafer transport device 19 is a robot for transporting wafers. The load ports 12, 14, and 16, the front-end module 18, and the first wafer transport device 19 are collectively called an Equipment Front End Module (EFEM) or enclosure.

[0012] Adjacent to the front-end module 18, a first load lock chamber (first LLC) 20 and a second load lock chamber (second LLC) 30 are provided. The first LLC 20 and the second LLC 30 are connected to a vacuum device and can be set to atmospheric pressure or vacuum. According to an example, the first LLC 20 and the second LLC 30 are two independent chambers, and the movement of gas from one to the other is prevented. Although two load lock chambers are shown in FIG. 1, three or more may be used.

[0013] A gate valve 22 is provided between the first LLC 20 and the front-end module (FEM) 18. A gate valve 32 is provided between the second LLC 30 and the FEM 18.

[0014] Adjacent to the first LLC 20 and the second LLC 3, a wafer handling chamber (WHC) 40 is provided. Inside the WHC 40, there is a second wafer transfer device 41. According to an example, the second wafer transfer device 41 is a robot for wafer transfer. A gate valve 24 is provided between the first LLC 20 and the WHC 40. A gate valve 34 is provided between the second LLC 30 and the WHC 40. Reactors 42, 44, 46, and 48 are adjacent to the WHC 40 via gate valves 42a, 44a, 46a, and 48a, respectively.

[0015] The WHC 40 is in contact with the WHC 60 via a pass-through chamber 50. According to an example, the pass-through chamber s 50 includes an upper pass-through chamber having a gate valve on the WHC 60 side and a lower pass-through chamber having a gate valve on the WHC 40 side. That is, there is one gate valve between the WHC 40 and the WHC 60 in both the upper pass-through chamber and the lower pass-through chamber. Thus, the pressures of the WHC 40 and the WHC 60 can be made different. [[ID=—14]]

[0016] [[ID=—15]] In the WHC60, reactor chambers 64, 66, 68, and 70 are adjacent to each other via gate valves 64a, 66a, 68a, and 70a, respectively. For example, reactor chambers 42, 44, 46, and 48, and reactor chambers 64, 66, 68, and 70 may be provided as an apparatus for forming epitaxial growth films on wafers in single-wafer processing. For example, the second wafer transfer apparatus 41 and the third wafer transfer apparatus 62 have two arms arranged vertically in a stack. The number of arms can be arbitrarily changed.

[0017] Wafer transport is controlled by the controller 28. For example, the controller 28 controls the first wafer transport device 19, the second wafer transport device 41, the third wafer transport device 62, and the aforementioned gate valves to transport the wafers along the wafer transport path specified in the control job.

[0018] The substrate processing apparatus 10 in Figure 1 can have a different configuration. For example, the pass-through chamber 50, WHC 60, and reactor chambers 64, 66, 68, and 70 can be omitted. In another example, the reactor chamber for single-wafer processing can be replaced with a Dual Chamber Module (DCM) or Quad Chamber Module (QCM), or with other batch processing chambers.

[0019] Figure 2 is a cross-sectional view of the first LLC20 and its vicinity. The first LLC20 has a plurality of wafer storage slots. In the example in Figure 2, 25 wafer storage slots 20a are provided. Therefore, the first LLC20 can store a maximum of 25 wafers. The 25 wafer storage slots 20a are supported by a shaft 20A. This shaft 20A can be raised and lowered by a drive such as a motor 20B. As the shaft 20A is raised and lowered, the 25 wafer storage slots 20a can also be raised and lowered. When placing wafers into or removing wafers from the first LLC20 using the first wafer transfer device 19 or the second wafer transfer device 41, the height of any wafer storage slot 20a is adjusted to match that of the first wafer transfer device 19 or the second wafer transfer device 41 using the aforementioned lifting and lowering function.

[0020] The second LLC30 can have the same configuration as the first LLC20. In this example, both the first LLC20 and the second LLC30 have multiple wafer storage slots.

[0021] The controller 28 controls, for example, the following wafer transport operations. (1) Wafer transfer by the first wafer transfer device 19 from one of the load ports 12, 14, or 16 to the first LLC 20 or the second LLC 30. (2) Wafer transfer from the first LLC20 or the second LLC30 to one of the reactor chambers 42, 44, 46, or 48 or to the pass-through chamber 50 by the second wafer transfer device 41. (3) Wafer transfer from pass-through chamber 50 to one of reactor chambers 64, 66, 68, or 70 by the third wafer transfer device 62. (4) Wafer transfer from one of the reactor chambers 64, 66, 68, or 70 to the pass-through chamber 50 by the third wafer transfer device 62. (5) Wafer transfer by the second wafer transfer device 41 from one of the reactor chambers 42, 44, 46, 48 or the pass-through chamber 50 to the first LLC20 or the second LLC30. (6) Wafer transfer from the first LLC20 or the second LLC30 to one of the load ports 12, 14, or 16 by the first wafer transfer device 19.

[0022] For example, these wafer transfers are performed according to the wafer transfer path specified by the control job. In addition to the wafer transfer described above, this substrate processing device has a function called FLEX-LL. FLEX-LL is a function that increases throughput through the movement of wafers between load lock chambers.

[0023] Figure 3 shows an example of the execution flowchart for FLEX-LL. First, in step S1, it is determined whether the execution conditions for FLEX-LL are met. These execution conditions are predetermined "wafer transport conditions". If it is determined that the wafer transport conditions are met, the process proceeds to step S2. In step S2, it is determined whether there are any conditions that restrict the execution of FLEX-LL. For example, if the control job prohibits the use of one of the load lock chambers, moving the substrate between the load lock chambers would violate the instructions of the control job, so the FLEX-LL function will not be executed. If it is determined in step S2 that there are no constraint conditions, FLEX-LL is executed in step S3, and the substrate is moved between the load lock chambers. Note that the above constraint conditions can also be considered when determining whether or not the wafer transport conditions are met.

[0024] (Example 1) Figures 4, 5A, 5B, and 5C show specific examples of FLEX-LL. In this example, first, in step S4, it is determined whether the wafer transport conditions are met. The wafer transport conditions in this example are that there are wafers in the first LLC20 and the second LLC30 that have not yet been processed, and that there is a wafer to be transported to either the first LLC20 or the second LLC30 in one of the load ports 12, 14, or 16.

[0025] Figure 5A shows the state when these wafer transport conditions are met. Wafer A is a wafer that leaves load port 12, is processed in the reactor chamber, and then returns to load port 12. Wafer B is a wafer that leaves load port 14, is processed in the reactor chamber, and then returns to load port 14. Wafer C is a wafer that leaves load port 16, is processed in the reactor chamber, and then returns to load port 16. In Figure 5A, nine wafers A before processing in the reactor chamber are in the first LLC20, eight wafers B before processing in the reactor chamber are in the second LLC30, and nine wafers C scheduled to move to the load lock chamber are in load port 16. When the controller 28 determines that these transport conditions are met, it proceeds to step S5.

[0026] In step S5, the controller 28 issues a command to the wafer moving device, which operates to ensure that there are no wafers in either the first LLC20 or the second LLC30.

[0027] Figure 5B shows that eight wafers B from the second LLC 30 have been moved to the first LLC 20. This wafer movement is performed by a "wafer moving device." The wafer moving device is, for example, the second wafer transport device 41. When wafer movement between load locks is performed by the second wafer transport device 41, the gate valves 24 and 34 must be in the open state. In another example, the "wafer moving device" can be a wafer transport device that is different from the wafer transport device shown in Figure 1 and is specialized for moving wafers between LLCs. After the processing in step S5 is completed, as shown in Figure 5B, there are no wafers left in the second LLC 30.

[0028] In one example, in step S5, the wafers stored in the first LLC20 and the wafers stored in the second LLC30 can be moved, with the wafer being moved if there are fewer wafers in the second LLC30. In the example in Figure 5, nine wafers A are stored in the first LLC20 and eight wafers B are stored in the second LLC30, so eight wafers B are moved to the first LLC20. This reduces the time required for wafer transport compared to moving all nine wafers A from the first LLC20 to the second LLC30. Of course, in another example, the wafer moving device can be operated to move wafers A to the second LLC30, resulting in a state where there are no wafers in the first LLC20.

[0029] Next, the process proceeds to step S6. In step S6, the controller 28 issues a command to the first wafer transport device 19 to move a wafer from one of the multiple load ports to the load lock chamber of the first LLC 20 or the second LLC 30 that does not contain a wafer. In the example in Figure 5C, it is shown that nine wafers are moved from load port 16 to the second LLC 30.

[0030] As shown in Figure 5A, when both the first LLC20 and the second LLC30 contain unprocessed wafers, both LLCs are under vacuum. Therefore, in this state, it is not possible to bring the LLCs to atmospheric pressure in order to transport wafers from the load port to the LLCs. In other words, wafers cannot be loaded from the load port into an LLC containing unprocessed wafers. However, by performing the FLEX-LL procedure described above and emptying one LLC, the empty LLC can be returned to atmospheric pressure, allowing wafers to be loaded. Once wafers are loaded into an LLC, the LLC is pressure-reduced to a vacuum over a period of time, for example, about 300 seconds, and can then be quickly processed in the reactor chamber. This increases throughput.

[0031] The examples in Figures 4 and 5 can be summarized as follows. Multiple load ports consist of a first load port, a second load port, and a third load port. The "wafer transport conditions" are that the first LLC20 contains wafers that have been transported from the first load port and whose processing is not yet complete, the second LLC30 contains wafers that have been transported from the second load port and whose processing is not yet complete, and the third load port contains wafers that should be transported to the first LLC or the second LLC. In other words, in the examples in Figures 4 and 5, nine wafers A, eight wafers B, and nine wafers C each form one group, and transport proceeds in units of these groups. The number of wafers in each group is not particularly limited. Transporting wafers in units associated with load ports in this way contributes to simplifying transport. Therefore, in this example, when moving wafers from one LLC to the other, all wafers to be returned to load port 12 (first wafers), all wafers to be returned to load port 14 (second wafers), or all wafers to be returned to load port 16 (third wafers) are moved. Here, any of wafers A, B, and C may be in LLC 20, any of wafers A, B, and C may be in LLC 30, and wafers waiting to be delivered to an LLC may be at any load port.

[0032] (Second example) Figures 6, 7A, 7B, and 7C show another specific example of FLEX-LL. In this example, in step S7, it is first determined whether the wafer transport conditions are met. In this example, the wafer transport conditions are that the first wafer, which has been processed, and the second wafer, which has not been processed, are mixed together in either the first LLC20 or the second LLC30.

[0033] Figure 7A shows an example of a state where these wafer transport conditions are met. That is, nine wafers A' processed in the reactor chamber and nine wafers B before processing are stored in the first LLC20. When the controller 28 determines that these transport conditions are met, the process proceeds to step S8.

[0034] In step S8, the controller issues a command to the wafer moving device, which operates to ensure that only wafer A' is present in either the first LLC20 or the second LLC30. To achieve this state where only wafer A' is present in the first LLC20, the nine wafers B in the first LLC20 are moved to the second LLC30 by the wafer moving device. As mentioned above, the wafer moving device is either the second wafer transport device 41 or a dedicated wafer transport device. Figure 7B illustrates that the wafers B have been moved to the second LLC30. Thus, only wafer A' is present in the first LLC20. In this example, when the controller issues a command to the wafer moving device and the wafer moving device moves wafers between load locks, it may adopt a movement pattern that minimizes the number of wafers moved between load locks. In another example, nine wafers C may be moved to the first LLC20, and nine wafers A' may be moved to the second LLC30, so that only wafer A' is present in the second LLC30.

[0035] Next, the process proceeds to step S9. In step S9, the processed wafers, wafers A', are returned to the load port. Figure 7C illustrates that the nine wafers A' of the first LLC20 have been returned to the load port 12. The first wafer transport device 19 can be used to move these wafers.

[0036] Next, the process proceeds to step S10. In step S10, the hoop containing wafer A' is removed from the load port 12. By using FLEX-LL in this way, processed wafers can be moved from the LLC to the load port earlier, increasing the number of available slots in the LL and speeding up the transport of processed wafers. Moving processed wafers from the LLC to the load port earlier also enables the loading of new wafers from the load port into the LLC.

[0037] The examples in Figures 6 and 7 can be summarized as follows. Multiple load ports have a first load port and a second load port. The "wafer transport condition" is that in either the first LLC or the second LLC, first wafers that have been transported from the first load port and processed are mixed with second wafers that have been transported from the second load port and processed. The command issued from the controller to the wafer moving device is to operate the wafer moving device so that only the first wafer is located in either the first LLC or the second LLC. In other words, in the example shown in Figures 6 and 7, nine wafers A', nine wafers B, and nine wafers C each form one group, and transport proceeds in units of these groups. The number of wafers in each group is not particularly limited. Transporting wafers in units associated with the load port in this way contributes to simplifying transport. Here, if unprocessed wafers are stored in one LLC, any of wafers A', B, and C may be in the first LLC 20, and any of wafers A', B, and C may be in the second LLC 30. In the second example, as in the first example, various modifications are possible. For example, although wafer A' is the wafer that has been processed and should be moved to the load port, this could also be wafer B', wafer C', or a mixture of wafers A', B', and C'.

[0038] (Third example) Figures 8A, 8B, and 8C show another specific example of FLEX-LL. This example has many similarities to the second example, and the flowchart is the same as Figure 6 which was referenced in the second example. The following will mainly explain the differences from the second example. The third example differs from the second example in that there is no wafer in the second LLC30 when FLEX-LL starts operating.

[0039] First, in step S7, it is checked whether the first LLC20 or the second LLC30 contains a mixture of first wafers that have been processed and second wafers that have not yet been processed. Figure 8A shows that the first LLC20 contains nine processed wafers A' and nine unprocessed wafers B. When the controller 28 determines that the transport conditions are met, the process proceeds to step S8.

[0040] Next, in step S8, the nine wafers B are moved to the second LLC 30. Figure 8B shows that the nine wafers B have been moved to the second LLC 30.

[0041] Next, in step S9, nine wafers A' are moved from the first LLC20 to the load port 12. Figure 8C illustrates the movement of wafers A' to the load port 12.

[0042] Next, in step S10, the hoop is unloaded from the load port 12. In this way, the FLEX-LL process allows wafer A' to be moved from the LLC to the load port at an early stage.

[0043] Throughput improvement can be achieved by performing wafer transfer between LLCs in a manner different from the first to third examples. In other words, the functions of FLEX-LL are not limited to the specific examples described above and can be in other forms. For example, any embodiment can be adopted that enables throughput improvement by moving wafers from multiple load ports to at least one of the first LLC and the second LLC, and by moving wafers from one of the first LLC and the second LLC to the other, thereby resulting in a state where there are no wafers in the first LLC or the second LLC, or where only processed wafers are present in the first LLC or the second LLC.

[0044] For example, the following constraints can be added to the wafer transport conditions exemplified in each of the above examples. Constraint 1: The process job specifying the wafer transport route must allow the use of both LLC 1 and LLC 2. More specifically, a constraint can be added requiring that both LLCs be available for a running control job or a control job that triggers the execution of FlexLL. In other words, if a control job is running or scheduled to run in which the user intentionally specifies either LLC1 or LLC2, the functionality of FLEX-LL may cause it to violate such specification, and therefore the wafer transport conditions of FLEX-LL will not be met.

[0045] Another example would show that the following constraints can also be added. Constraint 2: A single control job should not transport wafers belonging to multiple load ports. In other words, when dealing with a control job that simultaneously transports wafers entering and leaving one load port and wafers entering and leaving another load port, using FLEX-LL would complicate the transport logic (calculations), thus imposing the above constraints.

[0046] Another example would show that the following constraints can also be added. Constraint 3: No wafers entering or leaving a single load port are present in either the first or second LLC. For example, if wafer A is present in both the first LLC and the second LLC, then FLEX-LL Since the logic becomes complex, FLEX-LL may be not executed in such cases. As a variation of constraint condition 3, when a control job is supposed to transport wafers entering and leaving one load port to both the first LLC and the second LLC, FLEX-LL may be used to ensure that wafers entering and leaving one load port proceed only to either the first LLC or the second LLC.

[0047] Another example would show that the following constraints can also be added. Constraint 4: There is no restriction that only wafers entering and exiting through a single load port can be placed in a single LLC. For example, if only wafer A can be placed in a certain LLC, it is undesirable to move wafer A to another LLC, so this constraint can be imposed.

[0048] Incidentally, when moving wafers between LLCs, if the sum of the number of wafers to be moved in the source LLC and the number of wafers in the destination LLC is greater than 25, the wafer transfer between LLCs cannot be completed. Therefore, the controller may perform the wafer transfer between LLCs only after confirming that such a problem will not occur.

[0049] Figure 9 is a functional block diagram of the controller. The controller 28 may include a FLEX-LL condition determination unit 28A that determines whether or not the wafer transport conditions for executing FLEX-LL are met. Furthermore, it may include a constraint determination unit 28B that determines whether or not constraint conditions are met, if necessary. If no constraint conditions are added to the wafer transport conditions, the constraint determination unit 28B can be omitted. If both the condition determination unit 28A and the optionally provided constraint determination unit 28B determine that the conditions are met, the FLEX-LL execution unit 28C performs the wafer movement between the LLCs as described above.

[0050] Figure 10A shows an example configuration of the controller 28. The controller has a processing circuit 28X. The functions described above performed within the controller 28 are realized by the processing circuit 28X. Specifically, the processing circuit determines whether the wafer transport conditions are met, and if the wafer transport conditions are met, it issues a command to the wafer moving device to move the wafer between the first LLC 20 and the second LLC 30. The processing circuit 28X may be dedicated hardware (dedicated circuit) or a CPU (Central Processing Unit, also called a central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer, processor, or DSP) that executes a program stored in memory. If the processing circuit is dedicated hardware, the processing circuit may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination thereof. The determination of whether the processing conditions are met and the issuance of the command to the wafer moving device may be realized by separate processing circuits, or they may be realized together in a single processing circuit.

[0051] Figure 10B shows an example configuration of the controller 28 when the processing circuit is a CPU. In this case, each function of the controller 28 is realized by software or a combination of software and firmware. The software or firmware is written as a program and stored in memory 28CX. The processor 28Y realizes each function by reading and executing the program stored in memory 28Z. The processes in Figures 3, 4, and 6 are executed automatically. That is, the system is equipped with memory 28Z that stores a program in which the above-mentioned steps will be executed as a result when executed by the processing circuit. These programs can also be said to cause the computer to execute the procedures and methods of steps S1 to S3, S4 to S6, and S7 to S10. Here, memory refers to non-volatile or volatile semiconductor memory such as RAM, ROM, flash memory, EPROM, EEPROM, etc., magnetic disks, flexible disks, optical disks, compact disks, minidiscs, or DVDs. Naturally, some of the above functions may be realized by hardware and some by software or firmware.

[0052] Thus, each of the above functions is executed by the processor running a program stored in memory, or by processing with dedicated circuits.

[0053] In the example described above, the second wafer transfer device 41 was used to move the wafer from one of the first LLC 20 and the second LLC 30 to the other. However, wafer movement between LLCs can also be performed using a dedicated device. Figure 11-13 shows an example of such a dedicated wafer transfer device.

[0054] Figure 11 shows an example of the configuration of a wafer moving device. This wafer moving device comprises a load lock chamber 80, gate valves 82 and 84, and a load lock wafer transfer device 86. The load lock chamber 80 is connected to the first LLC 20 and the second LLC 30 via gate valves 82 and 84, respectively. The load lock wafer transfer device 86 is installed inside the load lock chamber 80. The load lock wafer transfer device 86 is, for example, a robot for wafer transfer. The load lock wafer transfer device 86 can be installed inside the load lock chamber 80, inside the first LLC, or inside the second LLC. When moving a wafer from one of the first LLCs to the other using the FLEX-LL function, the gate valves 82 and 84 are opened and the load lock wafer transfer device 86 is used to achieve this movement.

[0055] Figure 12 shows an example of the configuration of a wafer moving device in another example. A gate valve 90 is provided between the adjacent first LLC20 and second LLC30. When this gate valve 90 is opened, the first LLC20 and second LLC30 are connected, and when the gate valve 90 is closed, the movement of gas and materials between the first LLC20 and second LLC30 is blocked. In this example, the wafer moving device 91 is provided inside the second LLC30. The wafer moving device 91 is a robot, arm, or belt conveyor that moves a wafer from one of the first LLC20 and second LLC30 to the other when the gate valve 90 is open. The wafer moving device 91 can also be provided inside the first LLC20. In this example, a belt conveyor type wafer moving device 91 is shown.

[0056] Figure 13 illustrates the method of moving a wafer using the wafer moving device 91. When the gate valve 90 is open, the wafer moving device 91 is rotated in the XY plane so that it is extended in the wafer movement direction, i.e., in the X direction. In this state, the belt of the wafer moving device 91 is driven to move the wafer from one of the first LLC 20 and the second LLC 30 to the other.

[0057] As illustrated in Figure 11-13, by providing a dedicated wafer moving device, the second wafer transport device 41 can be used for other purposes while wafers are being moved between LLCs, thus further improvements in throughput can be expected. In addition, providing a dedicated wafer moving device enables wafer movement between LLCs without opening the gate valves 24 and 34. [Explanation of Symbols]

[0058] 10 Substrate processing unit, 12, 14, 16 Load ports, 18 Front-end module, 19 First wafer transfer unit, 20 First LLC, 28 Controller, 30 Second LLC, 40 WHC, 86 Inter-load lock wafer transfer unit, 90 Gate valve

Claims

1. Multiple load ports, A front-end module adjacent to the aforementioned multiple load ports, Adjacent to the front-end module is a first load lock chamber having a plurality of wafer storage slots, Adjacent to the front-end module is a second load lock chamber having a plurality of wafer storage slots, A wafer handling chamber adjacent to the first load lock chamber and the second load lock chamber, The first wafer transport device located within the front-end module, A second wafer transport device located inside the wafer handling chamber, A controller comprising a processor and memory, which determines whether predetermined wafer transport conditions are met by executing a program stored in the memory using the processor, or by processing a dedicated circuit, and if the wafer transport conditions are met, issues a command to the wafer moving device to move the wafer between the first load lock chamber and the second load lock chamber, The wafer transport conditions are that there are wafers in the first load lock chamber and the second load lock chamber that have not yet been processed, and that there is a wafer to be transported to the first load lock chamber or the second load lock chamber in one of the plurality of load ports. The command is a substrate processing apparatus that operates the wafer moving device to a state in which there is no wafer in either the first load lock chamber or the second load lock chamber.

2. Multiple load ports, A front-end module adjacent to the aforementioned multiple load ports, Adjacent to the front-end module is a first load lock chamber having a plurality of wafer storage slots, Adjacent to the front-end module is a second load lock chamber having a plurality of wafer storage slots, A wafer handling chamber adjacent to the first load lock chamber and the second load lock chamber, The first wafer transport device located within the front-end module, A second wafer transport device located inside the wafer handling chamber, A controller comprising a processor and memory, which determines whether predetermined wafer transport conditions are met by executing a program stored in the memory using the processor, or by processing a dedicated circuit, and if the wafer transport conditions are met, issues a command to the wafer moving device to move the wafer between the first load lock chamber and the second load lock chamber, The aforementioned plurality of load ports include a first load port, a second load port, and a third load port. The wafer transport conditions are that the first load lock chamber contains wafers that have been transported from the first load port and whose processing is not yet complete, the second load lock chamber contains wafers that have been transported from the second load port and whose processing is not yet complete, and the third load port contains wafers that should be transported to the first load lock chamber or the second load lock chamber. The command is a substrate processing apparatus that operates the wafer moving device to a state in which there is no wafer in either the first load lock chamber or the second load lock chamber.

3. The substrate processing apparatus according to claim 1, wherein when the program is executed by the processor or the processing of the dedicated circuit is executed, the controller issues a command to the first wafer transport device to move a wafer from one of the plurality of load ports to the load lock chamber of the first load lock chamber and the second load lock chamber that does not contain a wafer.

4. The substrate processing apparatus according to claim 1, wherein the command causes the wafer moving device to move the wafer whichever is fewer in number from the wafers stored in the first load lock chamber and the wafers stored in the second load lock chamber.

5. Multiple load ports, A front-end module adjacent to the aforementioned multiple load ports, Adjacent to the front-end module is a first load lock chamber having a plurality of wafer storage slots, Adjacent to the front-end module is a second load lock chamber having a plurality of wafer storage slots, A wafer handling chamber adjacent to the first load lock chamber and the second load lock chamber, The first wafer transport device located within the front-end module, A second wafer transport device located inside the wafer handling chamber, A controller comprising a processor and memory, which determines whether predetermined wafer transport conditions are met by executing a program stored in the memory using the processor, or by processing a dedicated circuit, and if the wafer transport conditions are met, issues a command to the wafer moving device to move the wafer between the first load lock chamber and the second load lock chamber, The wafer transport conditions are that a first wafer that has been processed and a second wafer that has not been processed are mixed together in either the first load lock chamber or the second load lock chamber. The command is a substrate processing apparatus that operates the wafer moving device to bring the first wafer into a state where only the first wafer is in either the first load lock chamber or the second load lock chamber.

6. Multiple load ports, A front-end module adjacent to the aforementioned multiple load ports, Adjacent to the front-end module is a first load lock chamber having a plurality of wafer storage slots, Adjacent to the front-end module is a second load lock chamber having a plurality of wafer storage slots, A wafer handling chamber adjacent to the first load lock chamber and the second load lock chamber, The first wafer transport device located within the front-end module, A second wafer transport device located inside the wafer handling chamber, A controller comprising a processor and memory, which determines whether predetermined wafer transport conditions are met by executing a program stored in the memory using the processor, or by processing a dedicated circuit, and if the wafer transport conditions are met, issues a command to the wafer moving device to move the wafer between the first load lock chamber and the second load lock chamber, The aforementioned plurality of load ports include a first load port and a second load port, The wafer transport conditions are such that the first load lock chamber or the second load lock chamber contains a mixture of first wafers that have been transported from the first load port and processed, and second wafers that have been transported from the second load port and processed. The command is a substrate processing apparatus that operates the wafer moving device to bring the first wafer into a state where only the first wafer is in either the first load lock chamber or the second load lock chamber.

7. The substrate processing apparatus according to claim 6, wherein the command causes the wafer moving device to move the wafer of the first wafer and the second wafer whichever is fewer in number.

8. Multiple load ports, A front-end module adjacent to the aforementioned multiple load ports, Adjacent to the front-end module is a first load lock chamber having a plurality of wafer storage slots, Adjacent to the front-end module is a second load lock chamber having a plurality of wafer storage slots, A wafer handling chamber adjacent to the first load lock chamber and the second load lock chamber, The first wafer transport device located within the front-end module, A second wafer transport device located inside the wafer handling chamber, A controller comprising a processor and memory, which determines whether predetermined wafer transport conditions are met by executing a program stored in the memory using the processor, or by processing a dedicated circuit, and if the wafer transport conditions are met, issues a command to the wafer moving device to move the wafer between the first load lock chamber and the second load lock chamber, The substrate processing apparatus is characterized in that the wafer transport conditions are such that a new wafer cannot be transported to the first load lock chamber or the second load lock chamber due to the storage of wafers in the first load lock chamber and the second load lock chamber.

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