Apparatus and method for processing a wafer
By introducing wafer storage and wafer loading/unloading devices into the wafer processing unit, a highly efficient wafer supply process has been achieved, solving the problem of low storage and transfer efficiency and improving the yield and storage capacity of produced wafers.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ASM IP HLDG BV
- Filing Date
- 2020-08-10
- Publication Date
- 2026-07-31
AI Technical Summary
In existing wafer processing equipment, the storage and transfer efficiency of filled and tested wafers is low, leading to cassette storage problems and reduced wafer production yield.
By introducing wafer storage, wafers can be efficiently transferred between wafer cassettes, wafer boats, and wafer storage via wafer loaders, thus optimizing the wafer supply process.
It improves the supply efficiency of filled and tested wafers, reduces cassette transfer time, and increases the yield and storage capacity of production wafers.
Smart Images
Figure CN112397428B_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to an apparatus for processing wafers. The apparatus includes:
[0002] A processing chamber for handling boats filled with wafers;
[0003] A wafer cassette loading and unloading device; and,
[0004] A wafer loading / unloading chamber is provided with a wafer loading / unloading device that transfers wafers from the wafer cassette for processing in the processing chamber. The invention also relates to a method for processing wafers. Background Technology
[0005] An apparatus for handling wafers may include a cassette loading / unloading chamber for loading and unloading wafer cassettes. The cassette loading / unloading chamber may accommodate cassettes for storing wafers. The cassette may be a standardized FOUP (front-opening cassette) wafer storage cassette for wafers with a diameter of 300 mm, or another type of standardized cassette for wafers with a diameter of 200 mm, which may have 25 slots for accommodating 25 wafers.
[0006] The cassette loading / unloading chamber may be equipped with a wafer cassette loading / unloading device that can transfer cassettes between input / output stations, wafer transfer stations, and / or cassette storage units. The apparatus may also include a wafer loading / unloading device by means of which wafers can be removed from cassettes placed at the wafer transfer station and placed in a wafer boat for processing in the apparatus's processing chamber.
[0007] During wafer processing within the batch furnace's processing chamber, it is beneficial to have available space within the filled wafer boat. Fill wafers can be used to fill the empty spaces between production wafers. When placed on top and / or bottom of the wafer stack within the wafer boat, fill wafers can serve as side fillers to improve the reactivity of production wafers placed between side fillers. Typically, fill wafers can be reused and can remain in the apparatus until cleaning is required.
[0008] Test wafers that can be used to test the processing in the processing chamber can also be used. Test wafers can be located between production wafers or fill wafers in a wafer boat and can be run through the processing chamber once before they are stored or used for testing.
[0009] When using filled and / or test wafers in the apparatus, storing these wafers in cassettes within the cassette loading / unloading chamber reduces the storage capacity for production wafers. For processes requiring large quantities of filled and / or test wafers, this can lead to cassette storage problems. An obvious solution is to increase the number of cassette receiving positions within the cassette loading / unloading chamber. However, such a solution requires additional space within the apparatus, which may be unavailable and / or expensive.
[0010] Transferring filled and / or test wafers from the cassette in the cassette loading / unloading chamber to the wafer loading / unloading chamber during each load can also be time-consuming. Wafer cassettes used for filling and / or testing may need to be specially transferred to and opened by a door opener, and since only a small number of filled and / or test wafers may need to be transferred from the cassette, this can take considerable time. During the transfer and door opening process, the door opener may become unavailable for wafer production, thus reducing the unit's throughput. Summary of the Invention
[0011] It may be desirable to provide an improved method and apparatus for supplying filling and / or testing wafers.
[0012] Therefore, an apparatus for processing wafers can be provided. The apparatus may include: a processing chamber for processing a boat filled with wafers; a wafer cassette loading / unloading chamber for loading and unloading wafer cassettes; and a wafer cassette loading / unloading chamber provided with a wafer loader that transfers wafers from the wafer cassette to the wafer boat for processing in the processing chamber. The wafer cassette loading / unloading chamber may be provided with a wafer storage unit, and the wafer loader may be configured and arranged to transfer wafers between the wafer storage unit, the wafer boat, and / or the wafer cassette.
[0013] By making wafer storage accessible to wafer loaders, the supply of filling and / or testing wafers can be improved.
[0014] Therefore, a method for processing wafers can be provided. The method may include:
[0015] Use a wafer loader to load production wafers from wafer cassettes into wafer boats;
[0016] The wafer loader is used to load filled and / or test wafers from the wafer storage into the wafer boat.
[0017] The wafer boat is moved to the processing chamber;
[0018] Processing, filling, and / or testing wafers in the wafer boat within the processing chamber;
[0019] Remove the wafer boat from the processing chamber; and
[0020] The wafer loader is used to unload production wafers from the wafer boat into the wafer cassette.
[0021] These and other embodiments will become apparent to those skilled in the art from the following detailed description of certain embodiments with reference to the accompanying drawings, and the invention is not limited to any particular embodiment disclosed. Attached Figure Description
[0022] It should be understood that the components in the figures are shown for simplicity and clarity only and are not necessarily drawn to scale. For example, the dimensions of some components in the figures may be enlarged relative to other components to aid in understanding the embodiments illustrated in this disclosure.
[0023] Figure 1 This is a perspective view of a first exemplary embodiment of the apparatus disclosed herein.
[0024] Figure 2 yes Figure 1 A top view of the first exemplary embodiment shown.
[0025] Figure 3 It is one of the providers of wafer memory. Figure 1 and 2 The first exemplary embodiment shown is a partially open side view.
[0026] The accompanying drawings are not to scale, and dimensions and thicknesses have been exaggerated, especially for clarity. Corresponding areas should be referred to using the same reference numerals whenever possible. Detailed Implementation
[0027] Figure 1 This is a perspective view of an exemplary embodiment of the wafer processing apparatus of this disclosure. The apparatus 1 is provided with two processing chambers 30 and 31, which can load wafer boats 34 from the bottom side, into which multiple wafers can be fed. The wafer boats 34 are arranged on a boat turntable 32, by means of which the boats 34 can be moved from one wafer to another. Figure 2 The wafer boat, clearly visible at the unloading and / or loading position 35, is brought to a processing position below the first processing chamber 30 or the second processing chamber 31. A lift 33 is provided below the two processing chambers 30, 31, by means of which the wafer boat containing the wafers can be lifted to bring it into the processing chambers 30, 31. Furthermore, opposite to the unloading and / or loading position 35, a cooling position 36 can be provided, at which the wafer boat containing the wafers 34, located on the turntable 32, can be cooled after processing in the processing chambers 30, 31.
[0028] Processing chambers 30 and 31 and a boat turntable 32 with a boat lift 33 are located in the rear chamber 39 of the apparatus. Walls 38 and 43 can create a wafer loader chamber 44 in the apparatus. A wafer loader 13 can be arranged in this wafer loader chamber 44, by means of which wafers can be placed in the wafer boat 34. The wafer boat 34 can be brought to the loading and / or unloading position 35 via a door in the wall 38 by means of a boat loading and unloading device 12, and can be removed from there and placed in the wafer loading and / or unloading position 46.
[0029] A portion of wall 43 includes a plurality of door openings defined by so-called door openers 18, 19. In this exemplary embodiment, door openers 18, 19 have two levels. Using such door openers 18, 19, the doors of wafer cassettes, also known in the prior art as FOUPs, can be opened and closed. For accurate description, reference is made to WO 99 / 38199, the contents of which are incorporated herein by reference.
[0030] The cassette loading / unloading chamber can be located on the side of the door openers 18 and 19 opposite to the wafer loading / unloading chamber 44. A large number of wafer cassettes 4 can be fed into the cassette loading / unloading unit 10 and the wafer cassette storage system 2. Two turntables 15 and 16 can also be located in the cassette loading / unloading chamber 45, on which the wafer cassettes 4 can be placed by the wafer cassette loading / unloading unit 10. The wafer cassettes 4 can be carried by the turntables 15 and 16 to the wafer transfer station before the door openers 18 and 19. The wafer cassettes 4 can be pressed against the door openers 18 and 19. The door openers 18 and 19 can open the wafer cassettes at the wafer transfer station, and the wafer loading / unloading unit 13 can transfer wafers between the wafer boat 34 and the wafer cassettes through the door opening.
[0031] The wafer cassette loader 10 can also be positioned such that it can remove the wafer cassette 4 from the input / output station 21 for placement in the storage system 2 or on the turntable 15 or 16. The input / output station 21 can be used to transfer the cassette 4 between the device and other wafer processing devices in the semiconductor factory where the device is located. Furthermore, an operation panel 20 is visible, allowing the operator to operate the device.
[0032] Figure 3 It shows Figure 1 and 2 The partially opened side view of the first exemplary embodiment shown illustrates a wafer memory 40 for storing filled and / or tested wafers. The wafer memory 40 may be configured... Figure 2 In wafer processing chamber 44.
[0033] The wafer loading / unloading chamber 44 may be provided with walls 38 and 43. The wafer storage 40 may be a wafer storage box, which has a box opening in the wall 43 in the direction of the wafer loading / unloading device 13. For example, the wafer storage box may be located in a portion of the wall 43 above the door openers 18 and 19. The door openers 18 and 19 may be constructed and arranged as doors to open the wafer cassette 4.
[0034] The wafer loader 13 can be configured and arranged to transfer wafers between the wafer storage 40, the wafer boat 34, and / or the wafer cassette 4. The wafer loader 13 may be provided with a movable wafer support for supporting the wafers. The wafer loader 13 may be provided with a horizontal driver to move the wafer support in a horizontal plane. The wafer loader 13 may be provided with a Z-driver to move the wafer support vertically from a minimum reach height to a maximum reach height in a vertical Z-direction substantially perpendicular to the horizontal plane.
[0035] The distance between the minimum and maximum reach heights can be approximately equal to the length of the wafer boat 34. The distance between the minimum and maximum heights can be at least the height of the door opening of the gate opener plus the height of the opening of the wafer memory 40.
[0036] The wafer storage unit 40 can be positioned above the door openers 18 and 19 in the wafer loading / unloading chamber 44. In this case, the top of the wafer storage unit 40 can be equal to or lower than the maximum reach height of the wafer support, so that all storage locations in the wafer storage unit 40 can be served by the wafer loading / unloading unit 13.
[0037] Alternatively, the wafer memory 40 can be positioned below the door openers 18 and 19. In this case, the bottom of the wafer memory 40 can be equal to or higher than the minimum reach height of the wafer support, so that all storage locations in the wafer memory 40 can be served by the wafer loader 13.
[0038] Alternatively, the wafer memory 40 can also be positioned between the two door openers 18 and 19. In this case, the bottom of the door opening of the lower door opener can be equal to or higher than the minimum reach height of the wafer support. The top of the door opening of the upper door opener can be equal to or lower than the maximum reach height of the wafer support. In this configuration, all storage locations in both door openers 18 and 19, as well as in the wafer memory, can be served by the wafer loader 13.
[0039] The wafer memory may include 2 to 50, preferably 3 to 30, and most preferably 4 to 25 wafer holders for holding the wafer. The wafer holders may include a flat surface to support the wafer.
[0040] The wafer holder of the wafer memory 40 may include slots for supporting wafers. The height of the wafer memory 40 can be less than, equal to, or greater than the height of the wafer cassette 4. The spacing between the slots in the wafer memory 40 can be less than the spacing between the slots in the wafer cassette 4, allowing the wafer memory to store more wafers than the wafer cassette. For a cassette 4 used to store wafers with a diameter of 300 mm, the spacing between the wafer slots in a standard wafer cassette 4 can be 10 mm. The spacing between the wafer slots in the wafer memory 40 can be, for example, between 3 and 9 mm, preferably between 4 and 8 mm, and most preferably between 5 and 7 mm.
[0041] The 10mm spacing of the wafer slots in the standardized wafer cassette 4 is chosen to ensure that wafers used for production within the standardized wafer cassette 4 can be loaded and unloaded by any wafer loading / unloading tool in the semiconductor fab. This requirement may be less stringent for filled and test wafers transferred to the wafer storage 40, as they can only be loaded and unloaded by a single dedicated wafer loader 13, which can also transfer them to the standard cassette 4. The smaller spacing of the wafer slots in the wafer storage 40 compared to the standardized wafer cassette 4 allows for potentially more wafer slots within the wafer storage 40 to store more wafers or to occupy less space in the wafer loader chamber 44.
[0042] Filling wafer storage 40 with filled and / or tested wafers can be performed as follows: A wafer cassette 4 containing filled and / or tested wafers can be introduced onto input / output station 21. The wafer cassette 4 containing filled and / or tested wafers can be transferred from input / output station 21 to storage system 2 and / or turntables 15, 16 with the aid of cassette loader 10. As turntables 15, 16 rotate, the cassette with filled and / or tested wafers can be placed against door openers 18, 19. With the door of wafer cassette 4 removed using door openers 18, 19, the filled and / or tested wafers can be directly transferred to wafer storage 40 by wafer loader 13. A portion of the filled and / or tested wafers can also be directly loaded into wafer boat 34, processed in reaction chambers 6, 7, and then unloaded into wafer storage 40. A fully loaded wafer cassette 4 with up to 25 filled and / or tested wafers can be unloaded by the wafer loader 13 by transferring the majority of the filled and / or tested wafers to the wafer storage 40. Since up to 25 tested and / or filled wafers can fill the entire wafer cassette 4 in this manner, the cassette opening and transfer capability can be effectively utilized.
[0043] Mass production wafers can be processed as follows: Multiple wafer cassettes 4 can be introduced onto input / output station 21. Each wafer cassette 4 can be transferred from input / output station 21 to storage system 2 and / or turntables 15, 16 by means of cassette loader 10. While turntables 15, 16 are rotating, the wafer cassettes can be placed against door openers 18, 19. After the doors of the wafer cassette 4 are removed by door openers 18, 19, the production wafers can be transferred to wafer boat 34 by wafer loader 13.
[0044] During wafer filling of wafer boat 34, the wafer loader can transfer filled and / or test wafers from wafer storage 40 to wafer boat 34. For example, filled and / or test wafers can be inserted into the top and bottom of wafer boat 34. Test wafers can be uniformly distributed on wafer boat 34.
[0045] After the substrate boat 34 has been filled with production wafers and filled and / or test wafers, the substrate boat 34 can be placed on the boat turntable 32 using the boat loading and unloading device 12. The boat turntable 32 can then move the wafer boat 34 to a position below the processing chambers 6 and 7 to be loaded. Then the elevator 33 can move the boat 34 into the processing chambers 6 and 7.
[0046] The processed substrate can perform the opposite movement described above. Fill and / or test wafers can be selected from production wafers and loaded into wafer storage 40 via wafer loader 13.
[0047] Filled wafers can be reused from wafer storage 40. Filled wafers can be stored in wafer storage 40 for later cleaning. When a reasonable number of used filled wafers (e.g., 10 to 25) exist in wafer storage 40, they can be transferred to a cassette for cleaning. Since 25 filled wafers can fill the entire cassette 4 in this manner, the cassette opening and transfer capability can be effectively utilized.
[0048] Test wafers can only be used once. Since only a limited number of test wafers are inserted into the wafer boat during each processing run, temporarily storing a large number of test wafers in the wafer storage saves space and time. When a reasonable number of used test wafers (e.g., 10 to 25) exist in the wafer storage 40, they can be transferred to a cassette for further processing. Since 25 test wafers can fill the entire cassette 4 in this way, the cassette opening and transfer capabilities can be utilized effectively.
[0049] It should be understood that the configurations and / or methods described herein are exemplary in nature, and these specific embodiments or examples should not be considered limitingly, as many variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. Therefore, the various actions shown may be performed in the order shown, in other orders, or in some cases may be omitted.
[0050] The subject matter of this disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems and configurations disclosed herein, as well as other features, functions, actions and / or properties and any and all equivalents thereof.
Claims
1. An apparatus for processing wafers, comprising: A processing chamber, the processing chamber being constructed and arranged to process a boat filled with wafers; A cassette loading / unloading chamber for loading and unloading wafer cassettes containing wafers; as well as, A wafer loading / unloading chamber is provided with a wafer loading / unloading device that transfers wafers from the wafer cassette to the wafer boat. The wafer loading / unloading chamber includes a wafer storage unit, and the wafer loading / unloading device is configured and arranged to transfer wafers between the wafer storage unit, the wafer boat, and / or the wafer cassette. The wafer memory includes 2 to 50 wafer holders for holding the wafer, and the wafer memory includes slots for supporting the wafer. The slot pitch of the wafer holder is smaller than the slot pitch of the wafer cassette, and the slot pitch of the wafer holder is between 4 and 8 millimeters. The wafer storage unit is configured to store more wafers than the wafer cassette. The wafer loading / unloading chamber is provided with a wall, and the wafer storage device is fixed in or to the wall. The wafer storage device is configured as a cassette, the cassette having a cassette opening in the wall in the direction of the wafer loader.
2. The apparatus of claim 1, wherein the cassette opening is disposed in a portion of the wall separating the cassette loading / unloading chamber from the wafer loading / unloading chamber.
3. The apparatus of claim 2, wherein the door opening of the wafer cassette opener is disposed in a portion of the wall separating the cassette loading / unloading chamber from the wafer loading / unloading chamber, and the cassette opening is located above or below the cassette door opening, and the wafer loading / unloading device is configured and arranged to transfer wafers between the wafer storage, the wafer boat, and / or the wafer cassette through the door opening and the cassette opening.
4. The apparatus of claim 1, wherein the cassette loading / unloading chamber is provided with a wafer cassette loading / unloading device for transferring cassettes between input / output stations, wafer transfer stations, and / or cassette storage devices.
5. The apparatus of claim 1, wherein the wafer loading / unloading device may be provided with a movable wafer support for supporting the wafer, a horizontal driver for moving the wafer support in a horizontal plane, and a Z driver for moving the wafer support up and down in a vertical Z direction substantially perpendicular to the horizontal plane from a minimum reach height to a maximum reach height.
6. The apparatus of claim 5, wherein the distance between the minimum height reached and the maximum height reached is approximately equal to the length of the boat.
7. The apparatus of claim 5, wherein the wafer storage has a wafer storage height on which wafers can be stored, and the wafer loading / unloading chamber is provided with one or more door openings, the one or more door openings being provided with wafer cassette openers for opening wafer cassettes, and the wafer storage is located above and / or below the one or more cassette openers, and the distance between the minimum height and the maximum height of the wafer loading / unloading chamber may be at least the height of the one or more door openings of the cassette openers plus the height of the wafer storage.
8. The apparatus of claim 1, wherein the filling and / or testing wafer storage is fixed to the wall of the wafer loading / unloading chamber.
9. A method for processing production wafers, comprising: Provide an apparatus for processing wafers according to any one of claims 1-8; Use a wafer loader to load multiple filled and / or test wafers from the first wafer cassette into the wafer storage unit; The production wafers contained in the second wafer cassette are loaded from the second wafer cassette into the wafer boat using a wafer loader; After the fill and / or test wafers are loaded into the wafer storage, at least one fill and / or test wafer is loaded from the wafer storage into the wafer boat using the wafer loader; The wafer boat is moved to the processing chamber; Processing, filling, and / or testing wafers in the wafer boat within the processing chamber; Remove the wafer boat from the processing chamber; The wafer loader unloads the filled and / or test wafers from the wafer boat into the wafer storage. as well as, The production wafers are unloaded from the wafer boat into the second wafer cassette using the wafer loader.
10. The method of claim 9, wherein the method comprises inserting a filled wafer into the top and bottom of the wafer boat.