Patent Application
20230207376
This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2021-212032, filed on Dec. 27, 2021, the entire contents of which are incorporated herein by reference.
The present disclosure relates to a substrate processing method and a substrate processing apparatus.
In Patent Document 1, there is known a technique of tilting and rotating a holding structure that holds a wafer during etching.
Patent Document 1: Japanese Laid-Open Publication No. 2017-98521
According to one embodiment of the present disclosure, there is provided a substrate processing method performed in a substrate processing apparatus including a processing container, a shower plate forming a ceiling wall of the processing container and configured to discharge gases used for a substrate processing, a stage arranged under the shower plate inside the processing container so as to face the shower plate and configured to mount a substrate thereon, and a drive mechanism configured to move the stage. The substrate processing method includes: a substrate processing process performing the substrate processing on the substrate in a state in which the stage is tilted by the drive mechanism so that a central axis of the stage, which passes through a center of a mounting surface mounted with the substrate and extends in a direction perpendicular to the mounting surface, forms a first angle other than 0° with respect to a predetermined reference axis of the shower plate, which extends in a vertical direction, while changing a position of the stage by the drive mechanism so that the central axis rotates around the reference axis while maintaining the first angle with respect to the reference axis.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure.
Reference will now be made in detail to various embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to one of ordinary skill in the art that the present disclosure may be practiced without these specific details. In other instances, well-known methods, procedures, systems, and components have not been described in detail so as not to unnecessarily obscure aspects of the various embodiments.
Hereinafter, embodiments of a substrate processing method and a substrate processing apparatus disclosed in the subject application will be described in detail with reference to the drawings. It should be noted that the disclosed substrate processing method and substrate processing apparatus are not limited by the following embodiments.
When substrate processing such as film formation or etching is performed on a substrate on which a recess is formed, an imbalance in the processing status of the substrate processing may occur in the upper portion and the lower portion of the side surface of the recess. As semiconductor devices have become highly integrated and miniaturized, the recess formed on a substrate becomes deeper and has a higher aspect ratio, and the imbalance in the processing status on the side surface of the recess becomes noticeable. Therefore, there is a demand for a technique capable of improving the imbalance in the processing status of the side surface of the recess formed on the substrate.
An example of a substrate processing apparatus according to the present disclosure will be described. In the embodiment described below, a case where the substrate processing apparatus of the present disclosure is used as a vacuum processing system having a system configuration will be described by way of example.
A carrier C, which is a transfer container containing substrates to be processed, is mounted on the loading/unloading port 11. The substrate is a wafer W, which is a circular substrate having a diameter of, for example, 300 mm. The loading/unloading module 12 is a module for loading and unloading the wafer W between the carrier C and the vacuum transfer module 13. The loading/unloading module 12 includes an atmospheric pressure transfer chamber 121 for transferring the wafer W to and from the carrier C in an atmospheric pressure atmosphere by a transfer mechanism 120, and a load lock chamber 122 configured to switch the atmosphere in which the wafer W is placed, between an atmospheric pressure atmosphere and a vacuum atmosphere.
The vacuum transfer module 13 has a vacuum transfer chamber 14 configured to maintain a vacuum atmosphere therein. A substrate transfer mechanism 15 is arranged inside the vacuum transfer chamber 14. The vacuum transfer chamber 14 is formed, for example, in a rectangular shape having long sides extending along the front-rear direction in a plan view. A plurality of (e.g., three) vacuum processing apparatuses 2 is connected to each of the rectangular long sides facing each other among the four side walls of the vacuum transfer chamber 14. A load lock chamber 122 installed in the loading/unloading module 12 is connected to the front short side among the four side walls of the vacuum transfer chamber 14. Gate valves G are arranged between the atmospheric pressure transfer chamber 121 and the load lock chamber 122, between the load lock chamber 122 and the vacuum transfer module 13, and between the vacuum transfer module 13 and the vacuum processing apparatus 2. The gate valves G are configured to open and close the loading/unloading ports for the wafer W provided in the respective modules connected to each other.
The substrate transfer mechanism 15 transfers the wafer W between the loading/unloading module 12 and the vacuum processing apparatuses 2 in a vacuum atmosphere. The substrate transfer mechanism 15 is composed of a multi joint arm and includes a substrate holder 16 for holding the wafer W thereon. The vacuum processing apparatus 2 performs substrate processing using a processing gas on multiple wafers W (e.g., four wafers W) at a time in a vacuum atmosphere. Therefore, the substrate holder 16 of the substrate transfer mechanism 15 is configured to hold, for example, four wafers W so as to collectively transfer the four wafers W to the vacuum processing apparatus 2.
Specifically, the substrate transfer mechanism 15 includes, for example, a base 151, a horizontally extending first arm 152, a horizontally extending second arm 153, and the substrate holder 16. The base side of the first arm 152 is provided on the base 151 so that the first arm 152 rotates about a vertical rotation axis on the base 151. The base side of the second arm 153 is provided on the tip portion of the first arm 152 so that the second arm 153 rotates about a vertical rotation axis on the tip portion of the first arm 152. The substrate holder 16 includes a first substrate holding portion 161, a second substrate holding portion 162, and a connecting portion 163. The first substrate holding portion 161 and the second substrate holding portion 162 are formed in the shape of two elongate spatula extending horizontally in parallel with each other. The connection portion 163 extends in a horizontal direction perpendicular to the extension direction of the first and second substrate holding portions 161 and 162, and connects the base ends of the first and second substrate holding portions 161 and 162 to each other. The central portion of the connecting portion 163 in the longitudinal direction is provided on the tip portion of the second arm 153 so that the connecting portion 163 rotates about a vertical rotation axis on the tip portion of the second arm 153. The first substrate holding portion 161 and the second substrate holding portion 162 will be described later.
The vacuum processing system 1 includes a controller 8. The controller 8 is, for example, a computer including a processor, a memory part, an input device, a display device, and the like. The controller 8 controls each part of the vacuum processing system 1. The controller 8 can use the input device to perform command input operations and the like for the operator to manage the vacuum processing system 1. In addition, the controller 8 can visualize and display the operation status of the vacuum processing system 1 using the display device. Furthermore, the memory part of the controller 8 stores a control program for controlling various processes executed in the vacuum processing system 1 by the processor, recipe data, and the like. The memory part may be a non-transient computer readable storage medium. Desired substrate processing is performed in the vacuum processing system 1 by the processor of the controller 8 executing the control program and controlling each part of the vacuum processing system 1 according to the recipe data.
Next, the vacuum processing apparatus 2 will be described with reference to
The six vacuum processing apparatuses 2 have the same configuration. The six vacuum processing apparatuses 2 can process wafers W in parallel. The vacuum processing apparatus 2 includes a processing container (vacuum container) 20 having a rectangular shape in a plan view. The processing container 20 is configured to maintain the inside thereof in a vacuum atmosphere. The processing container 20 is formed by closing the opening of a container body 202 having a concave opening on the upper surface thereof with a ceiling member 201. The processing container 20 has, for example, four side wall portions 203 surrounding the periphery of the processing container 20. Among the four side wall portions 203, the side wall portion 203 connected to the vacuum transfer chamber 14 is formed with two loading/unloading ports 21 arranged side by side in the front-rear direction (the Y′ direction in
As shown in
The stage 22 also serves as a lower electrode, and is formed in a flat cylindrical shape by, for example, metal or aluminum nitride (AlN) in which a metal mesh electrode is embedded. The stage 22 is configured to be movable by a drive mechanism 80. The drive mechanism 80 includes a rotary drive mechanism 600 and an adjustment mechanism 700. The stage 22 is supported from below by a support member 23. The support member 23 has a cylindrical shape, extends vertically downward, and penetrates the bottom portion 27 of the processing container 20. The lower end portion of the support member 23 is positioned outside the processing container 20 and connected to the rotary drive mechanism 600. The support member 23 can be rotated about the support member 23 as a rotation axis by the rotary drive mechanism 600. The stage 22 is configured to be rotatable according to the rotation of the support member 23. The adjustment mechanism 700 for adjusting the position and inclination of the stage 22 is provided at the lower end portion of the support member 23. The stage 22 is configured to be movable up and down between a processing position and a delivery position via the support member 23 by the adjustment mechanism 700. In
A heater 24 is embedded in the stage 22. The heater 24 heats each wafer W mounted on the stage 22 to about 60 degrees C. to 600 degrees C. Moreover, the stage 22 is connected to a ground potential.
In addition, the stage 22 is provided with plural pin through holes 26a (e.g., three pin through holes 26a). Lifter pins 26 are arranged inside the pin through holes 26a, respectively. The pin through holes 26a are provided so as to penetrate the stage 22 from the mounting surface (upper surface) of the stage 22 to the rear surface (lower surface) opposite to the mounting surface. The lifter pins 26 are slidably inserted into the pin through holes 26a. The upper ends of the lifter pins 26 are suspended from the mounting surface side of the pin through holes 26a. That is, the upper ends of the lifter pins 26 have a larger diameter than the pin through holes 26a. At the upper end of each of the pin through holes 26a, there is formed a recess having a larger diameter and thickness than the upper end of each of the lifter pins 26 and capable of accommodating the upper end of each of the lifter pins 26. As a result, the upper ends of the lifter pins 26 are locked to the stage 22 and suspended from the mounting surface side of the pin through holes 26a. In addition, the lower ends of the lifter pins 26 protrude from the rear surface of the stage 22 toward the bottom portion 27 of the processing container 20.
As shown in
Now, the first and second substrate holding portions 161 and 162 will be described. The first substrate holding portion 161 is configured to, when entering the first transfer space T1, hold the wafer W at a position corresponding to each of the arrangement positions of the processing spaces S1 and S2 in the first transfer space T1. The position corresponding to each of the arrangement positions of the processing spaces S1 and S2 in the first transfer space T1 refer to a position set so that the wafers W can be delivered to two stages 22 provided in the processing spaces S1 and S2 of the first transfer space T1. Further, the second substrate holding portion 162 is configured to, when entering the second transfer space T1, hold the wafer W at a position corresponding to each of the arrangement positions of the processing spaces S3 and S4 in the second transfer space T2. The position corresponding to each of the arrangement positions of the processing spaces S3 and S4 in the second transfer space T2 refer to a position set so that the wafers W can be delivered to two stages 22 provided in the processing spaces S3 and S4 of the second transfer space T2.
For example, the first and second substrate holding portions 161 and 162 are formed so that the widths of the first and second substrate holding portions 161 and 162 are smaller than the diameter of the wafer W. Each of the first and second substrate holding portions 161 and 162 supports two wafers W on the tip end side and the base end side thereof with a gap left therebetween. The wafers W supported on the tip end sides of the first and second substrate holding portions 161 and 162 are supported by, for example, the tip ends of the first and second substrate holding portions 161 and 162 at their central portions.
In this manner, for example, four wafers W are collectively transferred at the same time between the wafer transfer mechanism 15 and each stage 22 by the cooperative action of the substrate transfer mechanism 15, the lifter pins 26, and the stages 22.
A gas supplier 4 is provided on the ceiling member 201 of the processing container 20. The gas supplier 4 is provided above the stage 22 via a guide member 34 made of an insulating material. The gas supplier 4 has a function as an upper electrode. The gas supplier 4 includes a lid 42, a shower plate 43 facing the mounting surface of the stage 22 and forming a facing surface, and a gas flow chamber 44 formed between the lid 42 and the shower plate 43. A gas supply pipe 51 is connected to the lid 42. For example, the gas discharge holes 45 extending in the thickness direction are vertically and horizontally arranged in the shower plate 43. The shower plate 43 discharges a gas from each gas discharge hole 45 toward the stage 22 in a shower shape.
Each gas supplier 4 is connected to a gas supply system 50 via a gas supply pipe 51. The gas supply system 50 includes, for example, a supply source of a reaction gas (film forming gas), which is a processing gas, a supply source of a purge gas, a supply source of a cleaning gas, a pipe, a valve V, a flow rate adjuster M, and the like.
A high-frequency power source 41 is connected to the shower plate 43 via a matching device 40. The shower plate 43 functions as an upper electrode facing the stage 22. When high-frequency power is applied from the high-frequency power source 41 to between the shower plate 43, which is the upper electrode, and the stage 22, which is the lower electrode, the gas (e.g., the reaction gas in the example) supplied from the shower plate 43 to the processing space S1 is turned into plasma.
Next, the exhaust paths and the combined exhaust path formed in the intermediate wall portion 3 will be described. As shown in
Further, an exhaust port 33 is formed for each of the processing spaces S1 to S4 on the wall surface of the intermediate wall portion 3 positioned on the outer side of the processing spaces S1 to S4. Each exhaust path 31 is formed in the intermediate wall portion 3 so as to connect the exhaust port 33 and the combined exhaust path 32. For example, each exhaust path 31 extends horizontally within the intermediate wall portion 3 and then bends downward to extend vertically. Each exhaust path 31 is connected to the combined exhaust path 32. For example, each exhaust path 31 has a circular cross section (see
An exhaust guide member 34 is provided around each of the processing spaces S1 to S4 so as to surround each of the processing spaces S1 to S4. The guide member 34 is, for example, an annular body provided so as to surround the region around the stage 22 located at the processing position with a gap left with respect to the stage 22. The guide member 34 is configured to form therein a flow path 35 having, for example, a rectangular vertical cross section and an annular shape in a plan view.
As shown in
The guide members 34 fitted into the recess 204 form slit exhaust ports 36 opened toward the processing spaces S1 to S4. In this manner, the slit exhaust ports 36 are formed along the circumferential direction in the side peripheral portions of the respective processing spaces S1 to S4. The exhaust port 33 is connected to the flow path 35. The processing gas exhausted from the slit exhaust ports 36 is allowed to flow toward the exhaust port 33.
A set of two processing spaces S1 and S2 arranged along the extension direction of the first transfer space T1, and a set of two processing spaces S3 and S4 arranged along the extension direction of the second transfer space T2 are focused. As shown in
As a result, the flow paths of the processing gas extending from the respective processing spaces S1 to S4 to the combined exhaust path 32 via the slit exhaust ports 36, the flow paths 35 of the guide members 34, the exhaust ports 33, and the exhaust paths 31 are formed in a 180° rotational symmetry around the combined exhaust path 32. When focusing only on the flow paths of the processing gas by ignoring the positional relationship with the first and second transfer spaces T1 and T2 and the intermediate wall portion 3, it can be said that when viewed from above, the flow paths are formed in 90° rotational symmetry around the combined exhaust path 32.
The combined exhaust path 32 is connected to an exhaust pipe 61 via a combined exhaust port 205 formed in the bottom portion 27 of the processing container 20. The exhaust pipe 61 is connected via a valve mechanism 7 to a vacuum pump 62 forming an evacuation mechanism. For example, one vacuum pump 62 is provided for one processing container 20 (see
The valve mechanism 7 opens and closes a process gas flow path formed in the exhaust pipe 61. The valve mechanism 7 includes, for example, a casing 71 and an opening/closing part 72. A first opening 73 connected to the exhaust pipe 61 on the upstream side is formed on the upper surface of the casing 71. A second opening 74 connected to the exhaust pipe 61 on the downstream side is formed on the side surface of the casing 71.
The opening/closing part 72 includes, for example, an opening/closing valve 721 and an elevating mechanism 722. The opening/closing valve 721 is sized to block the first opening 73. The elevating mechanism 722 is provided outside the casing 71 to raise and lower the opening/closing valve 721 in the casing 71. The opening/closing valve 721 is configured to move up and down between a closed position that closes the first opening 73 as indicated by a one-dot chain line in
Next, the processing gas supply system will be described with reference to
The gas supply pipe 51 is also connected to a cleaning gas supply source 53 via a remote plasma unit (RPU) 531 by a cleaning gas supply path 532. The cleaning gas supply path 532 is branched into four cleaning gas supply paths on the downstream side of the RPU 531. The branched cleaning gas supply paths are connected to the gas supply pipes 51, respectively. On the upstream side of the RPU 531 in the cleaning gas supply path 532, a valve V1 and a flow rate adjuster M1 are provided. Further, on the downstream side of the RPU 531, valves V11 to V14 are provided for the respective branched pipes. During cleaning, the corresponding valves V11 to V14 are opened. For the sake of convenience,
When viewed from the processing gas distributed from the common gas supply path 52, the processing gas paths extending from the gas supply pipes 51 to the gas suppliers 4 are formed so as to have the same conductance. For example, as shown in
The first gas supply pipes 511 are formed so that the length from the upstream end (the end connected to the first common gas supply path 521) to the downstream end (the end connected to the gas supplier 4 or the gas supply pipe 51) and the inner diameter thereof are uniform between the first gas supply pipes 511. In addition, the second gas supply pipes 512 are formed so that the length from the upstream end (the end connected to the second common gas supply path 522) to the downstream end and the inner diameter thereof are uniform between the second gas supply pipes 512. In this way, when viewed from the processing gas distributed from the first common gas supply path 521, the respective processing gas supply paths extending to the combined exhaust path 32 via the first gas supply pipes 511, the gas suppliers 4, the processing spaces S1 to S4, and the exhaust paths 31 are formed to have the same conductance. In addition, when viewed from the processing gas distributed from the second common gas supply path 522, the respective processing gas supply paths extending to the combined exhaust path 32 via the second gas supply pipes 512, the gas suppliers 4, the processing spaces S1 to S4, and the exhaust paths 31 are formed to have the same conductance.
The vacuum processing apparatus 2 is connected to the controller 8 of the vacuum processing system 1. The controller 8 is, for example, a computer including a processor, a memory, a memory part, and the like. The controller 8 controls each part of the vacuum processing apparatus 2. The controller 8 allows an operator to use an input device to perform command input operations and the like for managing the vacuum processing apparatus 2. Further, in the controller 8, the operation status of the vacuum processing apparatus 2 can be visualized and displayed by a display device. Furthermore, the memory part of the controller 8 stores a control program for controlling various processes executed by the vacuum processing apparatus 2 using the processor, and recipe data. A desired process is executed in the vacuum processing apparatus 2 by the processor of the controller 8 executing the control program and controlling each part of the vacuum processing apparatus 2 according to the recipe data. For example, the controller 8 controls each part of the vacuum processing apparatus 2 to perform substrate processing such as an etching process, a film forming process, or the like on a substrate loaded into the vacuum processing apparatus 2.
The rotary drive mechanism 600 includes a rotary shaft 610, a motor 620, and a vacuum seal 630.
The rotary shaft 610 is connected to the lower end portion 23a of the support member 23 and configured to be rotatable integrally with the support member 23. A slip ring 621 is provided at the lower end of the rotary shaft 610. The slip ring 621 has electrodes and is electrically connected to various wirings for supplying electric power to components around the stage 22. For example, the slip ring 621 is electrically connected to a wiring for supplying electric power to the heater 24 embedded in the stage 22. Further, for example, when an electrostatic chuck for electrostatically attracting the wafer W is provided on the stage 22, the slip ring 621 is electrically connected to a wiring for a DC voltage applied to the electrostatic chuck.
The motor 620 is connected to the rotary shaft 610 to rotate the rotary shaft 610. When the rotary shaft 610 rotates, the stage 22 is rotated via the support member 23. When the rotary shaft 610 rotates, the slip ring 621 is also rotated together with the rotary shaft 610, and the electrical connection between the slip ring 621 and various wirings for supplying electric power to the components around the stage 22 is maintained.
The vacuum seal 630 is, for example, a ferrofluidic seal. The vacuum seal 630 is provided around the rotary shaft 610 to hermetically seal the rotary shaft 610 while maintaining the rotation of the rotary shaft 610.
The adjustment mechanism 700 is engaged with the lower end portion 23a of the support member 23 via the vacuum seal 630.
The adjustment mechanism 700 includes a base member 710, plural actuators 720 (e.g., six actuators 720), an absorption mechanism 730, and a bellows 740.
The base member 710 is engaged with the lower end portion 23a of the support member 23 positioned outside the processing container 20 via the vacuum seal 630 and is configured to be movable integrally with the stage 22. For example, the base member 710 includes a hole 711 having a larger diameter than the lower end portion 23a of the support member 23. The support member 23 passes through the hole 711 so that the lower end portion 23a thereof is connected to the rotary shaft 610. The vacuum seal 630 is provided around the rotary shaft 610 connected to the lower end portion 23a of the support member 23, and the base member 710 is fixed to the upper surface of the vacuum seal 630. Thus, the base member 710 is connected to the stage 22 via the vacuum seal 630, the rotary shaft 610, the support member 23 and the like, and can be moved integrally with the stage 22.
The actuators 720 are provided in parallel with each other between the bottom portion 27 of the processing container 20 and the base member 710. The actuators 720 move the base member 710 relative to the bottom portion 27 of the processing container 20 to adjust the position and inclination of the stage 22. Each of the actuators 720 is extendable and contractible. Each of the actuators 720 is rotatably and slidably connected to the base member 710 via a universal joint, and is rotatably and slidably connected to the bottom portion 27 of the processing container 20 via a universal joint. The actuators 720 and the base member 710 form a parallel link mechanism that can move the base member 710, for example, in the directions of the X′, Y′ and Z′ axes shown in
The position and inclination of the stage 22 adjusted by the actuators 720 can be specified by detecting the position and inclination of the base member 710 using various detection means. Examples of the detection means include a linear encoder, a gyro sensor, a triaxial acceleration sensor, a laser tracker, and the like.
By the way, in the vacuum processing apparatus 2, when the pressure inside the processing container 20 is switched from the atmospheric pressure to the vacuum pressure, the processing container 20 is deformed due to the pressure difference. In addition, the temperature of the processing container 20 is changed due to the transfer of heat during the substrate processing performed in the processing container 20, and the processing container 20 is also deformed due to the temperature change. When the processing container 20 is deformed, the stress generated due to the deformation of the processing container 20 may be transmitted to the stage 22, and the position and inclination of the stage 22 may be changed.
Therefore, in the vacuum processing apparatus 2 according to the present embodiment, the actuators 720 are provided between the bottom portion 27 of the processing container 20 and the base member 710 that can move integrally with the stage 22. The actuators 720 adjust the position and inclination of the stage 22 by moving the base member 710 relative to the bottom portion 27. Accordingly, even when the position and inclination of the stage 22 are changed due to the deformation of the processing container 20, the position and inclination of the stage 22 can be adjusted to the original position and inclination. As a result, the vacuum processing apparatus 2 according to the present embodiment can improve the deviation of the position and inclination of the stage 22 caused by the deformation of the processing container 20. As a result, it is possible to improve the in-plane uniformity in the substrate processing such as a film forming process or the like.
The absorption mechanism 730 is provided in the bottom portion 27 of the processing container 20 to absorb deformation of the bottom portion 27 of the processing container 20. The absorption mechanism 730 is formed with a hole 731 that communicates with the inside of the processing container 20 through the hole 27a of the bottom portion 27 of the processing container 20. The actuators 720 are connected to the absorption mechanism 730 without being directly connected to the bottom portion 27 of the processing container 20. As a result, even if the bottom portion 27 of the processing container 20 is deformed, the stress generated by the deformation of the bottom portion 27 of the processing container 30 is absorbed by the absorption mechanism 730 and is not transmitted to the actuators 720. This makes it possible to suppress a decrease in the adjustment accuracy of the position and inclination of the stage 22. Details of the absorption mechanism 730 will be described later.
A bellows 740 is provided so as to surround the support member 23. The bellows 740 has an upper end connected to the bottom portion 27 of the processing container 20 through a hole 731 formed in the absorption mechanism 730 and a lower end connected to the base member 710. Thus, the bellows 740 hermetically seals the space between the bottom portion 27 of the processing container 20 and the base member 710. The bellows 740 is configured to expand and contract in response to the movement of the base member 710. For example, when the base member 710 is moved in the direction perpendicular to the outer wall surface of the bottom portion 27 of the processing container 20 (e.g., the Z′-axis direction in
Now, an example of the configuration of the absorption mechanism 730 will be described with reference to
The plate member 732 is formed in a disk shape and arranged below the bottom portion 27 of the processing container 20. From the viewpoint of blocking the transmission of heat and vibration from the processing container 20, the plate member 732 is spaced apart from the outer wall surface of the bottom portion 27 of the processing container 20.
The rod member 733 has one end, which is rotatably and slidably connected to the bottom portion 27 of the processing container 20, and the other end, which is rotatably and slidably connected to the plate member 732. That is, a recess 27b is formed on the outer wall surface of the bottom portion 27 of the processing container 20, and a spherical bearing 27c that can freely rotate and slide is attached to the recess 27b. One end portion 733a of the rod member 733 is connected to the spherical bearing 27c, whereby it can be rotatably and slidably connected to the bottom portion 27 of the processing container 20. On the other hand, a recess 732a is formed on the upper surface of the plate member 732 at a position corresponding to the recess 27b, and a spherical bearing 732b that can freely rotate and slide is attached to the recess 732a. The other end 733b of the rod member 733 is connected to the spherical bearing 732b, whereby it is rotatably and slidably connected to the plate member 732. The rod member 733 suppresses transmission of deformation to the plate member 732 by rotating in a direction corresponding to the deformation of the bottom portion 27 of the processing container 20. For example, when the bottom portion 27 of the processing container 20 is deformed in the direction of the arrow shown in
Further, the rod members 733 are arranged at plural circumferential positions of the plate member 732. For example, three rod members 733 are provided along the circumferential direction of the plate member 732 at plural positions inside the edge at equal intervals. Four or more rod members 733 may be provided at equal intervals along the circumferential direction of the plate member 732.
Next, a brief description will be given on the flow of a film forming process performed on the wafer W by the vacuum processing system 1 according to the embodiment.
The controller 8 controls the substrate transfer mechanism 15 to transfer the wafer W toward the vacuum processing apparatus 2. The controller 8 calculates the amount of deviation of the wafer W transferred by the substrate transfer mechanism 15 as the correction amount of the position of the wafer W. The correction amount of the position of the wafer W is calculated by, for example, detecting the amount of deviation between the wafer W and the target position of the transfer by the substrate transfer mechanism 15 using a position detection sensor provided at an arbitrary position on the transfer path of the wafer W. The position detection sensor is provided, for example, inside the vacuum transfer chamber 14 in which the substrate transfer mechanism 15 is arranged. Further, the position detection sensor may be provided at the loading/unloading port 21 of the vacuum processing apparatus 2. The target position is a position where the wafer W is mounted on the stage 22, and is, for example, a position where the center of the stage 22 and the center of the wafer W are coincident with each other.
The controller 8 controls the actuators 720 so that the base member 710 is moved from a predetermined reference position by the calculated correction amount. The reference position is a position at which the center of the stage 22 raised to the processing position should be positioned. For example, the reference position is a position where the center of the stage 22 and the center of the shower plate 43 (for example, the center of the region in which the gas discharge holes 45 are formed) are coincident with each other. The reference position is determined, for example, when the vacuum processing apparatus 2 is designed or when the vacuum processing apparatus 2 is adjusted.
As the base member 710 moves, the stage 22 also moves from the reference position by the correction amount. The controller 8 also controls the actuators 720 so that the base member 710 moves downward (i.e., in the negative direction of the Z′ axis in
When the substrate transfer mechanism 15 reaches the vacuum processing apparatus 2, the controller 8 controls the substrate transfer mechanism 15 to transfer the wafer W to above the target position in the processing container 20. At this stage, the center of the stage 22 and the center of the wafer W are coincident with each other.
The controller 8 delivers the wafer W between the stage 22 and the substrate transfer mechanism 15. For example, the controller 8 controls the actuators 720 so that the base member 710 moves to the reference position. For example, the controller 8 controls the actuators 720 so that the base member 710 moves upward (i.e., in the positive direction of the Z′ axis in
As described above, in the vacuum processing apparatus 2, instead of moving the substrate transfer mechanism 15 by the correction amount, the base member 710 and the stage 22 are integrally moved by the correction amount, and the wafer W is delivered. Therefore, the transfer load of the substrate transfer mechanism 15 can be reduced. As a result, the throughput of the entire vacuum processing system 1 can be improved.
For each vacuum processing apparatus 2, the controller 8 transfers the wafers W in parallel to the four processing spaces S1 to S4 in the processing container 20 of the vacuum processing apparatus 2. As a result, when the substrate transfer mechanism 15 transfers four wafers W to the four processing spaces S1 to S4 in the processing chamber 20 at the same time, the wafers W can be delivered between the stage 22 and the substrate transfer mechanism 15 at the same time. As a result, the throughput of the entire vacuum processing system 1 can be further improved.
The controller 8 performs the film forming process on the wafers W in the four processing spaces S1 to S4 for each vacuum processing apparatus 2. For example, the controller 8 controls the elevating mechanism 722 and the vacuum pump 62 to open the opening/closing valve 721, and the vacuum pump 62 reduces the pressure inside the processing container 20. The controller 8 controls the gas supply system 50, supplies various gases used for film formation from the gas supply system 50, and introduces various gases from the respective gas suppliers 4 into the processing spaces S1 to S4. Further, the controller 8 rotates the stage 22 by the drive mechanism 80. For example, the controller 8 controls the rotary drive mechanism 600 to rotate the support member 23 that supports the stage 22, thereby rotating the stage 22. Then, the controller 8 controls the high-frequency power sources 41, supplies high-frequency power from the high-frequency power sources 41, generates plasma in the processing spaces S1 to S4, and performs the film forming process on the wafer W. The controller 8 may rotate the stage 22 as necessary. Further, the controller 8 may stop the support member 23 without rotating it, and may perform the film forming process on the wafer W without rotating the stage 22.
When substrate processing such as film formation and etching is performed on a substrate such as a wafer W in which a recess is formed, the processing status of the substrate may be imbalanced between the upper portion and the lower portion of the side surface of the recess. As semiconductor devices have become highly integrated and miniaturized, the recess formed on a substrate becomes deeper and has a higher aspect ratio, and the imbalance in the processing status on the side surface of the recess becomes noticeable.
Therefore, in the present embodiment, the controller 8 causes the stage 22 to be tilted by the drive mechanism 80 so that, during the film forming process, the central axis of the stage 22, which passes through the center of the mounting surface mounted with the wafer W and extends in a direction perpendicular to the mounting surface, forms an angle θ other than 0° with respect to a predetermined reference axis of the shower plate 43, which extends in the vertical direction. During the film forming process, the controller 8 performs substrate processing on the wafer W while causing the drive mechanism 80 to change the position of the stage 22 so that the central axis rotates around the reference axis while maintaining the angle θ with respect to the reference axis.
The drive mechanism 80 according to the present embodiment can cause the six actuators 720 of the adjustment mechanism 700 to move the stage 22 along the X, Y and Z axes and in the rotation directions about the three axes. Thus, the drive mechanism 80 can change the angle, the direction, and the position at which the stage 22 is tilted. As a result, the drive mechanism 80 can arbitrarily change the central position of the inclination of the mounting surface 93. For example, the drive mechanism 80 can set the central position of the inclination of the mounting surface 93 to the center of the upper surface of the mounting surface 93, the center of the wafer W, or a position higher than the center of the wafer W by 50 mm.
The controller 8 causes the drive mechanism 80 to tilt the stage 22 so that the central position of inclination of the mounting surface 93 is located on the central axis 94, and the central axis 94 forms an angle θ with respect to the reference axis 95.
For example, the controller 8 causes the drive mechanism 80 to tilt the stage 22 so that the central axis 94 forms an angle θ with respect to the reference axis 95 in a state in which the center of the upper surface of the wafer W mounted on the mounting surface 93 is located at an intersection of the reference axis 95 and the central axis 94.
The controller 8 may cause the drive mechanism 80 to tilt the stage 22 so that the central axis 94 forms an angle θ with respect to the reference axis 95 in a state in which the center of the upper surface of the mounting surface 93 is located at an intersection of the reference axis 95 and the central axis 94.
The angle θ is set to any angle in the range of −0.1° to +0.1°. For example, the angle θ is set to 0.1°. This can prevent the wafer W from slipping on the stage 22.
By tilting the stage 22, the wafer W mounted on the stage 22 is tilted with respect to the shower plate 43 together with the stage 22. When the wafer W is tilted with respect to the shower plate 43, the recess 91 formed on the wafer W has a surface where a deposition rate increases and a surface where a deposition rate decreases.
The controller 8 performs a film forming process on the wafer W while causing the drive mechanism 80 to change the position of the stage 22 during the film forming process so that the central axis 94 rotates around the reference axis 95 while maintaining the angle θ with respect to the reference axis 95.
It is preferable that the rotation speed at which the central axis 94 rotates around the reference axis 95 during the film forming process is π [rad/sec] or less. This can prevent the wafer W from slipping on the stage 22. Further, the gas flow on the upper surface of the wafer W can follow the movement of the stage 22, and the film forming process can be performed on the wafer W stably.
The controller 8 controls the drive mechanism 80 during the film forming process, and causes the drive mechanism 80 to change the position of the stage 22 so that the central axis 94 rotates around the reference axis 95 plural times. It is preferable that the controller 8 performs control so that the central axis 94 rotates around the reference axis 95 an integral number of times during the film forming process. Since the central axis 94 rotates around the reference axis 95 plural times during the film forming time as described above, it is possible to perform a film forming process uniformly on the side surfaces of the recess 91 in the respective directions.
Further, the controller 8 may dynamically change the angle θ during the film forming process. For example, the controller 8 may dynamically change the angle θ each time when the central axis 94 makes one turn around the reference axis 95. For example, the controller 8 may gradually increase the angle θ to 0.01° in a first period, 0.03° in a second period, 0.05° in a third period, and so on. The controller 8 may gradually reduce the angle θ after half the process has passed. By dynamically changing the angle θ in this manner, it is possible to perform a film forming process uniformly on the side surfaces of the recess 91 in the respective directions.
Further, in the case of the configuration in which four processing spaces S1 to S4 are provided in the processing container 20 of the vacuum processing apparatus 2 so that four wafers W can be processed in parallel as in the present embodiment, the controller 8 may control each drive mechanism 80 so as to cancel the vibration of the processing spaces S1 to S4 caused by the movement of the stage 22. For example, in the processing spaces S1 to S4, the controller 8 rotates the central axes 94 in the same direction by shifting the starting positions of rotation of the central axes 94 with respect to the reference axis 95 by 90°. For example, in the processing spaces S1 to S4, the controller 8 rotates the central axes 94 in the same direction with respect to the respective reference axis 95 while setting the positions on the side of the combined exhaust path 32 to the starting positions of rotation. As a result, in the processing spaces S1 and S4, and the processing spaces S2 and S3, which are located diagonally in the processing container 20, the starting positions of rotation are shifted by 180°, and the vibrations are generated in opposite directions. As a result, the vibrations can cancel each other out so as to reduce the vibrations.
As described above, in the vacuum processing apparatus 2 according to the present embodiment, during the film forming process, by changing the direction of the tilt of the stage 22 in the circumferential direction in a state in which the stage 22 is tilted with respect to the shower plate 43, the side surface on the lower side of the recess 91 is changed sequentially. As a result, a film can be formed sequentially on the entire side surface of the recess 91, and the imbalance in the film forming status on the side surface of the recess 91 can be improved.
Next, a specific example of the flow of the substrate processing method according to the embodiment will be described.
The controller 8 evacuates the processing space S1 of the processing container 20 (step S10). For example, the controller 8 performs the evacuation with the vacuum pump 62 and evacuates the processing space S1 from the surroundings of the stage 22 with the guide member 34.
The controller 8 causes the drive mechanism 80 to tilt the stage 22 so that the central axis 94 forms an angle θ with respect to the reference axis 95. The controller 8 performs a film forming process on the wafer W while changing the position of the stage 22 so that the central axis 94 rotates around the reference axis 95 while maintaining the angle θ (step S11).
As a result, the vacuum processing apparatus 2 can improve the imbalance in the processing status of the side surface of the recess 91.
As described above, the substrate processing method according to the embodiment is a substrate processing method performed in a substrate processing apparatus (e.g., the vacuum processing system 1 or the vacuum processing apparatus 2). The substrate processing apparatus includes a processing container 20, a shower plate 43, a stage 22, and a drive mechanism 80. The shower plate 43 constitutes a ceiling wall of the processing container 20 and discharges gases used for substrate processing (e.g., a film forming process). The stage 22 is arranged under the shower plate 43 inside the processing container 20 so as to face the shower plate 43, and is configured to mount a wafer W having a recess 91 thereon. The drive mechanism 80 is configured to move the stage 22. The substrate processing method includes a substrate processing process (e.g., step S11). In the substrate processing process, the stage 22 is tilted by the drive mechanism 80 so that the central axis 94 of the stage 22, which passes through the center of the mounting surface 93 mounted with the wafer W and extends in a direction perpendicular to the mounting surface 93, forms a first angle (angle θ) other than 0° with respect to a predetermined reference axis 95 of the shower plate 43, which extends in the vertical direction. In the substrate processing process, substrate processing is performed on the wafer W while changing the position of the stage 22 by the drive mechanism 80 so that the central axis 94 rotates around the reference axis 95 while maintaining the first angle with respect to the reference axis 95. As a result, the substrate processing method according to the embodiment can improve the imbalance in the processing status of the side surface of the recess 91.
In the substrate processing method according to the embodiment, during the substrate processing process, the stage 22 is tilted by the drive mechanism 80 so that the central axis 94 forms the first angle with respect to the reference axis 95 in a state in which the center of the upper surface of the wafer W mounted on the mounting surface 93 is located at an intersection of the reference axis 95 and the central axis 94. In the substrate processing method, during the substrate processing process, the position of the stage 22 is changed by the drive mechanism 80 so that the central axis 94 rotates around the reference axis 95 while maintaining the first angle with respect to the reference axis 95. Thus, the substrate processing method according to the embodiment can keep the distance between the center of the upper surface of the wafer W and the shower plate 43 constant. This allows the process to be performed without being affected by plasma imbalance. Moreover, the symmetry of a gas flow is less likely to collapse, which contributes to the uniformity of substrate processing.
In the substrate processing method according to the embodiment, during the substrate processing process, the stage 22 is tilted by the drive mechanism 80 so that the central axis 94 forms the first angle with respect to the reference axis 95 in a state in which the center of the upper surface of the mounting surface 93 is located at an intersection of the reference axis 95 and the central axis 94. Further, in the substrate processing method, during the substrate processing process, the position of the stage 22 is changed by the drive mechanism 80 so that the central axis 94 rotates around the reference axis 95 while maintaining the first angle with respect to the reference axis 95. Thus, the substrate processing method according to the embodiment can keep the distance between the center of the upper surface of the wafer W and the shower plate 43 constant. This allows the process to be performed without being affected by plasma imbalance. Moreover, the substrate processing can be performed while suppressing the collapse of the symmetry of a gas flow.
The reference axis 95 is a vertical axis that passes through the center of the shower plate 43. Accordingly, in the substrate processing method according to the embodiment, the substrate processing can be performed symmetrically about the central axis 94 with respect to the stage 22.
Further, in the substrate processing method according to the embodiment, during the substrate processing process, the position of the stage 22 is changed by the drive mechanism 80 so that the central axis 94 rotates around the reference axis 95 plural times. As a result, the substrate processing method according to the embodiment can suppress the imbalance in the processing result of the substrate processing on the side surfaces of the recess 91 in the respective directions even if the substrate processing is not uniform in a part of the substrate processing period such as a first half period or a second half period.
Further, the first angle is set to any angle in a range of −0.1° to +0.1°. Thus, the substrate processing method according to the embodiment can prevent the wafer W from slipping on the stage 22.
Further, in the substrate processing method according to the embodiment, during the substrate processing process, the position of the stage 22 is changed by the drive mechanism 80 so that the central axis 94 rotates around the reference axis 95 at a rotation speed of π [rad/sec] or less. Accordingly, in the substrate processing method according to the embodiment, the gas flow on the upper surface of the wafer W can follow the movement of the stage 22, and the wafer W can be stably subjected to substrate processing.
Although the embodiment has been described above, the embodiment disclosed herein should be considered as exemplary and not restrictive in all respects. The embodiment described above may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the claims.
For example, in the above-described embodiment, there has been described an example where the vacuum processing apparatus 2 is an apparatus that performs a film forming process as substrate processing. However, the present disclosure is not limited thereto. The substrate processing may be, for example, an etching process such as plasma etching or the like, or may be any substrate processing. The disclosed technique may be applied to any apparatus that performs other substrate processing such as plasma etching and the like.
Further, in the above-described embodiment, the case where the substrate is the wafer W has been described by way of example. However, the present disclosure is not limited thereto. The substrate may be any substrate such as, for example, a glass substrate or the like.
According to the present disclosure in some embodiments, it is possible to improve the imbalance in a processing status of a side surface of a recess formed on a substrate.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosures. Indeed, the embodiments described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions, and changes in the form of the embodiments described herein may be made without departing from the spirit of the disclosures. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosures.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-212032 | Dec 2021 | JP | national |
