WO2019244782A1 - Substrate processing device, substrate processing method, and storage medium - Google Patents

Abstract

An application/development device provided with: a heat plate configured such that a wafer to be processed can be mounted thereon; a lifting/lowering mechanism configured to lift and lower a support pin supporting a wafer so that the wafer can be mounted on the heat plate; a suction unit which provides a plurality of regions on a back surface of the wafer with suction force so that the wafer is suction-attached onto the heat plate; and a controller which estimates warpage information pertaining to the wafer on the basis of a pressure change in each of first pipes of the suction unit as the wafer approaches the heat plate.

Description

Substrate processing apparatus, substrate processing method, and storage medium

The present disclosure relates to a substrate processing apparatus, a substrate processing method, and a storage medium.

With changes in semiconductor processes such as pattern lamination, application and development processing requirements for warped substrates (wafers) are increasing. For warped substrates, the same reliability, productivity, Process performance is required.

For example, in the substrate processing apparatus described in Patent Literature 1, a suction unit that suctions a substrate from the hot plate side is provided, and the substrate is corrected for warpage. The process is being implemented.

JP 2016-119337 A

Here, in the conventional method, the process is performed without grasping the warpage information (warpage amount, warpage shape, etc.) of the substrate in advance. As a result, for example, even when the warpage of the substrate is corrected using the technique of Patent Document 1, the same reliability, productivity, and process performance as those of a flat substrate have not been realized. .

The present disclosure has been made in view of the above circumstances, and has as its object to easily grasp warpage information of a substrate.

A substrate processing apparatus according to an aspect of the present disclosure includes a mounting unit configured to mount a substrate to be processed, and at least a substrate and a mounting unit such that the substrate is mounted on the mounting unit. An elevating unit configured to be able to move up or down one of them, a plurality of suction units for applying a suction force to a plurality of regions on the back surface of the substrate so that the substrate is adsorbed to the mounting unit, A control unit for estimating warpage information of the substrate based on a pressure change in each of the plurality of suction units in response to approaching the mounting unit.

In the substrate processing apparatus according to the present disclosure, in a state where the back surface of the substrate is sucked by the suction unit (the substrate is sucked in the direction of the mounting unit), the warpage information of the substrate is estimated based on the pressure change in the suction unit. You. Here, when the substrate has a warped shape, the timing at which the substrate is mounted on the mounting portion differs in each region. When a certain region of the substrate approaches the mounting portion, the pressure measured in the suction portion that applies a suction force to the region changes. As described above, by detecting a pressure change in each suction unit, it is possible to specify an area of the substrate that is closer to the mounting unit among the respective areas. By performing such pressure change detection for each suction unit, it is possible to estimate substrate unevenness information (warpage information). In the substrate processing apparatus according to the present disclosure, such estimation of substrate warpage information can be easily performed using an existing configuration such as a suction unit and a lifting unit. That is, according to the substrate processing apparatus according to the present disclosure, it is possible to easily estimate warpage information of a substrate.

The elevating unit raises and lowers the substrate so as to bring the substrate closer to the mounting unit, and the control unit determines whether the pressure change amount of the suction unit is equal to or more than a predetermined value, and the pressure change amount is equal to or more than the predetermined value. In this case, the height information of the substrate may be obtained from the lifting unit, and the amount of warpage of the substrate may be estimated based on the height information. Thereby, for example, when the separation distance between the corresponding region of the substrate and the mounting portion is equal to or less than a predetermined distance (when the amount of pressure change in that case is reached), the height information of the substrate is obtained, and The amount of warpage is estimated. By estimating the amount of warpage of the substrate in this manner, warpage information of the substrate can be estimated with higher accuracy.

The control unit may estimate the warped shape of the substrate according to a difference in timing at which the pressure change amount becomes equal to or more than a predetermined value for each of the plurality of suction units. From the timing when the pressure change amount becomes equal to or more than a predetermined value, that is, when the separation distance from the mounting portion becomes equal to or less than the predetermined distance, any region of the substrate has a shape (concave shape) close to the mounting portion, It is possible to specify which region has a shape (convex shape) far from the mounting portion. Therefore, it is possible to highly accurately estimate the warped shape of the substrate (which area is concave and which area is convex) by considering the difference in timing when the pressure change amount becomes a predetermined value or more. it can.

The control unit controls the plurality of suction units so that each of the plurality of suction units applies a suction force at a different timing from each other, and performs a suction operation among the plurality of suction units prior to the first control. The second control for controlling a plurality of suction units may be performed for each group including two or more suction units that do not cause mutual interference of forces. From the viewpoint of preventing mutual interference between the suction units, the suction units are basically provided with the suction force at mutually different timings (the first control is performed). On the other hand, such control alone may require a long time for warpage estimation. In this regard, prior to the first control, the suction force is applied to each group of two or more suction units that do not mutually interfere with each other (the second control is performed), so that the suction force is not mutually interfered. While preventing interference, rough warpage information can be estimated before the first control. By performing detailed estimation of the first control after obtaining the general warpage information, it is possible to shorten the estimation time and improve the accuracy.

(4) In the second control, the control unit may arrange the two suction units that apply the suction force to the regions adjacent to each other on the back surface of the substrate as different groups. As a result, mutual interference of suction forces can be effectively prevented.

The control unit may control the suction unit to increase the volume of the suction unit after estimating the amount of warpage of the substrate. Thereby, for example, when estimating the amount of warpage of the substrate, the volume of the suction unit is reduced (suction force is reduced) to easily detect a pressure change during suction (that is, to easily estimate the amount of warpage), and After that, when the substrate is sucked, the volume of the suction unit is increased (the suction force is increased), so that the substrate can be appropriately sucked.

The control unit may determine the suction timing of each of the plurality of suction units based on the warpage information of the substrate, and may control the plurality of suction units such that the suction force is applied at the determined suction timing. By applying the suction force by each suction unit at a timing according to the warpage information, it is possible to sequentially apply the suction force from the suction unit corresponding to the area where the distance to the placement unit is short. Thus, the substrate can be quickly sucked without causing the problem of emptying, which is a problem when the application of the suction force is started from the suction unit corresponding to the region far from the mounting unit. .

The control unit may determine the suction amount of each of the plurality of suction units based on the warp information of the substrate, and may control the plurality of suction units such that the suction force is applied with the determined suction amount. Thus, for example, the suction force can be increased in a region farther from the mounting portion, and the substrate can be appropriately sucked.

The mounting section may be a hot plate for heating the substrate, and the control section may adjust the temperature distribution in the hot plate based on the warpage information of the substrate. Thereby, it is possible to heat appropriately according to the distance between the mounting portion and the region of the substrate.

The elevating unit raises and lowers the substrate so that the substrate approaches the mounting unit, and the control unit controls at least one of the elevating amount and the elevating speed of the elevating unit based on the warpage information of the substrate. Good. When a substrate having a warped shape is transferred between the elevating unit and the cool arm, as in a normal substrate, interference between the cool arm and the substrate may be problematic. In addition, when a substrate having a warped shape is placed on the mounting portion from the elevating portion in the same manner as a normal substrate, if the substrate is a normal substrate, it is not the timing of mounting on the mounting portion, but the elevating speed. Even when the speed is increased, the warped substrate may come into contact with the mounting portion, which may cause a problem that the contact speed of the substrate with the mounting portion increases. In this regard, by controlling the amount of elevating and lowering the elevating unit and the elevating speed of the elevating unit based on the warpage information of the substrate, it is possible to suppress the above-described problem from occurring.

A substrate processing method according to another aspect of the present disclosure is configured to apply a suction force to a plurality of regions of a substrate placed on a mounting portion and change according to the proximity of the substrate to the mounting portion. And estimating substrate warpage information based on a change in pressure according to the application of suction force.

A storage medium according to another embodiment of the present disclosure is a computer-readable storage medium storing a program for causing an apparatus to execute the above-described substrate processing method.

According to the present disclosure, it is possible to easily grasp the warpage information of the substrate.

It is a perspective view showing the schematic structure of the substrate processing system concerning a 1st embodiment. FIG. 2 is a sectional view taken along line II-II in FIG. 1. FIG. 3 is a sectional view taken along the line III-III in FIG. 2. FIG. 3 is a schematic longitudinal sectional view illustrating an example of a heat treatment unit. FIG. 4 is a diagram illustrating a configuration related to wafer warpage information estimation in a heat treatment unit. It is a figure explaining the example of formation of the adsorption hole in a hot plate. It is a figure explaining judgment of a pressure change. FIG. 3 is a hardware configuration diagram of a controller. 4 is a flowchart illustrating substrate processing. It is a flowchart which shows a rough estimation process. It is a flowchart which shows this estimation processing. It is a flowchart which shows a suction control process. FIG. 9 is a diagram for explaining a problem of a conventional example. FIG. 9 is a diagram for explaining a problem of a conventional example. It is a figure explaining the heat processing unit concerning a 2nd embodiment. It is a graph which shows a hot plate temperature behavior.

[First Embodiment]
Hereinafter, the first embodiment will be described in detail with reference to the drawings. In the description, the same elements or elements having the same functions will be denoted by the same reference symbols, without redundant description.

[Substrate processing system]
The substrate processing system 1 is a system for forming a photosensitive film, exposing the photosensitive film, and developing the photosensitive film on the substrate. The substrate to be processed is, for example, a semiconductor wafer W. The photosensitive film is, for example, a resist film.

The substrate processing system 1 includes a coating / developing device 2 and an exposure device 3. The exposure device 3 performs an exposure process on the resist film formed on the wafer W. Specifically, an energy beam is applied to the exposed portion of the resist film by a method such as immersion exposure. The coating / developing device 2 performs a process of forming a resist film on the surface of the wafer W before the exposure process by the exposure device 3, and performs a developing process of the resist film after the exposure process.

(Coating and developing equipment)
Hereinafter, the configuration of the coating and developing apparatus 2 will be described as an example of the substrate processing apparatus. As shown in FIGS. 1 to 3, the coating and developing apparatus 2 includes a carrier block 4, a processing block 5, an interface block 6, and a controller 100.

(4) The carrier block 4 introduces the wafer W into the coating and developing device 2 and derives the wafer W from the coating and developing device 2. For example, the carrier block 4 can support a plurality of carriers 11 for the wafer W and has a built-in transfer arm A1. The carrier 11 accommodates a plurality of circular wafers W, for example. The transfer arm A1 takes out the wafer W from the carrier 11 and transfers it to the processing block 5, receives the wafer W from the processing block 5, and returns the wafer W into the carrier 11.

The processing block 5 includes a plurality of processing modules 14, 15, 16, and 17. As shown in FIGS. 2 and 3, the processing modules 14, 15, 16, and 17 include a plurality of liquid processing units U1, a plurality of heat treatment units U2, and a transfer arm A3 that transfers a wafer W to these units. Built-in. The processing module 17 further incorporates a direct transfer arm A6 that transfers the wafer W without passing through the liquid processing unit U1 and the heat treatment unit U2. The liquid processing unit U1 applies a processing liquid to the surface of the wafer W. The heat treatment unit U2 incorporates, for example, a hot plate and a cooling plate, heats the wafer W with the hot plate, and cools the heated wafer W with the cooling plate to perform heat treatment.

The processing module 14 forms a lower layer film on the surface of the wafer W by the liquid processing unit U1 and the heat treatment unit U2. The liquid processing unit U1 of the processing module 14 applies a processing liquid for forming an underlayer film onto the wafer W. The heat treatment unit U2 of the processing module 14 performs various heat treatments associated with the formation of the lower layer film.

The processing module 15 forms a resist film on the lower layer film by the liquid processing unit U1 and the heat treatment unit U2. The liquid processing unit U1 of the processing module 15 applies a processing liquid (coating liquid) for forming a resist film on the lower layer film. The heat treatment unit U2 of the processing module 15 performs various heat treatments associated with the formation of the resist film. The details of the liquid processing unit U1 of the processing module 15 will be described later.

The processing module 16 forms an upper layer film on the resist film by the liquid processing unit U1 and the heat treatment unit U2. The liquid processing unit U1 of the processing module 16 applies a processing liquid for forming an upper layer film on the resist film. The heat treatment unit U2 of the treatment module 16 performs various heat treatments associated with the formation of the upper layer film.

(4) The processing module 17 performs a developing process on the exposed resist film by the liquid processing unit U1 and the heat treatment unit U2. The liquid processing unit U1 of the processing module 17 applies a processing liquid for development (developing liquid) on the surface of the exposed wafer W, and then rinses it with a processing liquid for cleaning (rinse liquid), thereby forming a resist. The film is developed. The heat treatment unit U2 of the processing module 17 performs various heat treatments associated with the development processing. Specific examples of the heat treatment include a heat treatment (PEB: Post \ Exposure \ Bake) before the development treatment and a heat treatment (PB: Post \ Bake) after the development treatment.

棚 A shelf unit U10 is provided on the carrier block 4 side in the processing block 5. The shelf unit U10 is partitioned into a plurality of cells arranged vertically. An elevating arm A7 is provided near the shelf unit U10. The lifting arm A7 raises and lowers the wafer W between cells of the shelf unit U10. On the interface block 6 side in the processing block 5, a shelf unit U11 is provided. The shelf unit U11 is partitioned into a plurality of cells arranged vertically.

The interface block 6 exchanges the wafer W with the exposure apparatus 3. For example, the interface block 6 has a built-in transfer arm A8 and is connected to the exposure apparatus 3. The transfer arm A8 transfers the wafer W placed on the shelf unit U11 to the exposure device 3, receives the wafer W from the exposure device 3, and returns the wafer W to the shelf unit U11.

The controller 100 controls the coating / developing device 2 so as to execute the coating / developing process in the following procedure, for example.

{Circle around (1)} First, the controller 100 controls the transfer arm A1 so as to transfer the wafer W in the carrier 11 to the shelf unit U10, and controls the lifting arm A7 so as to arrange the wafer W in the cell for the processing module 14.

Next, the controller 100 controls the transfer arm A3 to transfer the wafer W of the shelf unit U10 to the liquid processing unit U1 and the heat treatment unit U2 in the processing module 14, and forms a lower layer film on the surface of the wafer W. The liquid processing unit U1 and the heat treatment unit U2 are controlled as described above. Thereafter, the controller 100 controls the transfer arm A3 to return the wafer W on which the lower layer film is formed to the shelf unit U10, and controls the lifting arm A7 to arrange the wafer W in the cell for the processing module 15.

Next, the controller 100 controls the transfer arm A3 to transfer the wafer W of the shelf unit U10 to the liquid processing unit U1 and the heat treatment unit U2 in the processing module 15, and forms a resist film on the lower layer film of the wafer W. Control the liquid processing unit U1 and the heat treatment unit U2. Thereafter, the controller 100 controls the transfer arm A3 to return the wafer W to the shelf unit U10, and controls the lifting arm A7 to arrange the wafer W in the cell for the processing module 16.

Next, the controller 100 controls the transfer arm A3 to transfer the wafer W of the shelf unit U10 to each unit in the processing module 16, and the liquid processing unit so as to form an upper layer film on the resist film of the wafer W. U1 and the heat treatment unit U2 are controlled. Thereafter, the controller 100 controls the transfer arm A3 to return the wafer W to the shelf unit U10, and controls the lifting arm A7 to arrange the wafer W in the cell for the processing module 17.

Next, the controller 100 directly controls the transfer arm A6 so as to transfer the wafer W of the shelf unit U10 to the shelf unit U11, and controls the transfer arm A8 so as to send out the wafer W to the exposure apparatus 3. Thereafter, the controller 100 controls the transfer arm A8 so as to receive the exposed wafer W from the exposure apparatus 3 and return the wafer W to the shelf unit U11.

Next, the controller 100 controls the transfer arm A3 to transfer the wafer W of the shelf unit U11 to each unit in the processing module 17, and performs the liquid processing unit U1 and the liquid processing unit U1 so that the resist film on the wafer W is subjected to the development processing. The heat treatment unit U2 is controlled. Thereafter, the controller 100 controls the transfer arm A3 to return the wafer W to the shelf unit U10, and controls the lifting arm A7 and the transfer arm A1 to return the wafer W to the inside of the carrier 11. Thus, the coating / developing process is completed.

The specific configuration of the substrate processing apparatus is not limited to the configuration of the coating / developing apparatus 2 exemplified above. The substrate processing apparatus is not limited as long as it has a liquid processing unit U1 for forming a film (the liquid processing units U1 of the processing modules 14, 15, and 16) and a controller 100 that can control the liquid processing unit U1. Good.

[Heat treatment unit]
Subsequently, the heat treatment unit U2 of the processing module 15 will be described in detail with reference to FIGS. As shown in FIGS. 4 and 5, the heat treatment unit U2 includes a housing 90, a temperature adjustment mechanism 50, a heating mechanism 30, a suction unit 70 (see FIG. 5), and a controller 100 (control unit). Have. 4 and 5 show only a part of the configuration of the heat treatment unit U2, and do not show all the configurations of the heat treatment unit U2.

The housing 90 is a processing container that houses the heating mechanism 30 and the temperature adjustment mechanism 50. An entrance 91 for the wafer W is opened in the side wall of the housing 90. Further, a floor plate 92 is provided in the housing 90 to partition the inside of the housing 90 into an upper area, which is a movement area of the wafer W, and a lower area.

The temperature adjusting mechanism 50 is configured to transfer (transfer) the wafer W between the hot plate 34 and the external transfer arm A3 (see FIG. 3), and to adjust the temperature of the wafer W to a predetermined temperature. The temperature adjustment mechanism 50 has a temperature adjustment plate 51 and a connection bracket 52.

The temperature adjustment plate 51 is a plate for adjusting the temperature of the placed wafer W. More specifically, the temperature adjustment plate 51 places the wafer W heated by the hot plate 34 of the heating mechanism 30 and cools the wafer W to a predetermined temperature. It is a cool plate. In the present embodiment, the temperature adjustment plate 51 is formed in a substantially disk shape. The temperature adjusting plate 51 is made of, for example, a metal having high thermal conductivity, such as aluminum, silver, or copper, and may be made of the same material from the viewpoint of preventing deformation due to heat. Inside the temperature adjustment plate 51, a cooling channel (not shown) for flowing cooling water and / or cooling gas is formed.

The connection bracket 52 is connected to the temperature adjustment plate 51 and is driven by a drive mechanism 53 controlled by the controller 100 to move inside the housing 90. More specifically, the connection bracket 52 is movable along a guide rail (not shown) extending from the entrance 91 of the housing 90 to the vicinity of the heating mechanism 30. When the connection bracket 52 moves along a guide rail (not shown), the temperature adjustment plate 51 can move from the carry-in entrance 91 to the heating mechanism 30. The connection bracket 52 is made of a metal having a high thermal conductivity, such as aluminum, silver, or copper.

The heating mechanism 30 is configured to heat the wafer W. The heating mechanism 30 has a support table 31, a top plate section 32, an elevating mechanism 33, a support pin 35, an elevating mechanism 36 (elevating section), and a hot plate 34 (mounting section).

The support base 31 is a member having a cylindrical shape with a concave portion formed at the center. The support table 31 supports the hot plate 34. The top plate part 32 is a disk-shaped member having a diameter similar to that of the support base 31. The top plate 32 faces the support 31 via a gap, for example, while being supported by the ceiling of the housing 90. An exhaust duct 37 is connected to an upper portion of the top plate 32. The exhaust duct 37 exhausts the inside of the chamber.

The elevating mechanism 33 is configured to elevate and lower the top plate 32 under the control of the controller 100. When the top plate 32 is raised by the elevating mechanism 33, the chamber, which is a space for performing the heat treatment of the wafer W, is opened, and when the top plate 32 is lowered, the chamber is closed. It becomes.

The support pins 35 are members that extend through the support table 31 and the hot plate 34 and support the wafer W from below. The support pins 35 move the wafer W at predetermined positions by moving up and down in the vertical direction. The support pins 35 are configured to transfer the wafer W to and from the temperature adjustment plate 51 that transports the wafer W. The three support pins 35 are provided, for example, at equal intervals in the circumferential direction. The elevating mechanism 36 is configured to elevate and lower the support pins 35 under the control of the controller 100. The elevating mechanism 36 is configured to move the wafer W (specifically, the support pins 35 supporting the wafer W) so that the wafer W is brought close to the hot plate 34 and the wafer W is placed on the hot plate 34. Have been.

(4) The hot plate 34 is fitted into the concave portion of the support table 31 and is configured so that the wafer W to be processed can be mounted thereon, and heats the mounted wafer W. The hot plate 34 has a heater for heating the wafer W. The heater is composed of, for example, a resistance heating element. The heat plate 34 is formed with first suction holes 34a to 34c and second suction holes 34d to 34f penetrating in the thickness direction. The first suction holes 34a to 34c and the second suction holes 34d to 34f will be described with reference to FIG.

As shown in FIG. 6, four first suction holes 34a are formed at equal intervals on the circumference of a circle centered on the center of the heating plate 34. Eight first suction holes 34b are formed at regular intervals on the circumference of a circle formed outside the circle indicating the formation area of the first suction holes 34a. Twelve first suction holes 34c are formed at equal intervals on the circumference of a circle formed outside the circle concentrically with the circle indicating the formation region of the first suction holes 34b. The second suction holes 34d are formed at positions corresponding to the respective first suction holes 34a (specifically, inside the first suction holes 34a). The second suction holes 34e are formed at positions corresponding to the respective first suction holes 34b (specifically, inside the first suction holes 34b). The second suction holes 34f are formed at positions corresponding to the respective first suction holes 34c (specifically, inside the first suction holes 34c). The first suction holes 34a to 34c and the second suction holes 34d to 34f are formed in a region facing the back surface of the wafer W when the wafer W is placed on the hot plate 34.

The first suction holes 34a to 34c are suction holes selected when the suction force from the suction unit 70 is applied to the wafer W in order to correct (flatten) the warped wafer W (details are described in detail). See below). The second suction holes 34d to 34f are suction holes selected when applying a suction force from the suction unit 70 to the wafer W in order to estimate a warped shape of the wafer W (details will be described later). The diameters of the first suction holes 34a to 34c are larger than the diameters of the second suction holes 34d to 34f. The hole diameters of the first suction holes 34a to 34c are, for example, φ1 mm to 5 mm, and the hole diameters of the second suction holes 34d to 34f are, for example, φ0.5 mm to 1 mm. By making the diameters of the first suction holes 34a to 34c relatively large, it becomes possible to apply a strong suction force to the wafer W, and it is possible to appropriately correct the warpage. By making the hole diameters of the second suction holes 34d to 34f relatively small, it is possible to apply a suction force that is not too strong to the wafer W and to estimate the original shape of the wafer W without correcting the shape of the wafer W. Become. In addition, by reducing the diameter of the second suction holes 34d to 34f, when detecting a pressure change in the estimation stage (details will be described later), a small pressure change is detected sensitively and the detection speed (reaction speed of the sensor) is reduced. Can be hastened.

(4) The suction unit 70 applies a suction force to a plurality of regions on the back surface of the wafer W so that the wafer W is suctioned to the hot plate 34. The suction unit 70 applies a suction force to the back surface of the wafer W via the first suction holes 34a to 34c or the second suction holes 34d to 34f. As shown in FIG. 5, the suction unit 70 has a suction means 71, first pipes 72a to 72c, pressure sensors 73a to 73c, valves 74a to 74c, and second pipes 75d to 75f.

The suction means 71 is a mechanism for sucking up gas by the action of pressure. One end of each of the first pipes 72a to 72c is connected to the suction means 71, and the other end thereof passes through the first suction holes 34a to 34c and is the upper end of the first suction holes 34a to 34c (the portion facing the wafer W). Has been reached. That is, the first pipe 72a extends so as to connect the suction means 71 and the upper end of the first suction hole 34a, and the first pipe 72b extends so as to connect the suction means 71 and the upper end of the first suction hole 34b. The first pipe 72c extends so as to connect the suction means 71 and the upper ends of the first suction holes 34c. The first pipes 72a to 72c have a configuration in which the other ends extend only to the entrances (lower ends) of the first suction holes 34a to 34c (the first pipes 72a to 72c pass through the first suction holes 34a to 34c). Configuration).

The pressure sensors 73a to 73c are provided corresponding to the first pipes 72a to 72c, and detect (measure) the pressure in the first pipes 72a to 72c. That is, the pressure sensor 73a is provided in the first pipe 72a, the pressure sensor 73b is provided in the first pipe 72b, and the pressure sensor 73c is provided in the first pipe 72c. The pressure sensors 73a to 73c transmit the detected pressure values to the controller 100.

The valves 74a to 74c are provided corresponding to the first pipes 72a to 72c, and open and close the flow paths in the first pipes 72a to 72c. The second pipes 75d to 75f are connected to the valves 74a to 74c. That is, the valve 74a is provided in the first pipe 72a and connected to the second pipe 75d, the valve 74b is provided in the first pipe 72b and connected to the second pipe 75e, and the valve 74c is provided in the first pipe The second pipe 75f is connected to the second pipe 72c. By closing the flow path to the second pipes 75d to 75f in the valves 74a to 74c and opening the flow path to the first pipes 72a to 72c, the processing vessel 21 through the first suction holes 34a to 34c. The gas inside is sucked up to the suction means 71 side. Further, by closing the flow path to the first pipes 72a to 72c and opening the flow path to the second pipes 75d to 75f in the valves 74a to 74c, the processing is performed through the second suction holes 34d to 34f. The gas in the container 21 is sucked up to the suction means 71 side. Further, by adjusting the opening of the valves 74a to 74c, the amount of gas suction to the suction means 71 side is adjusted. The opening and closing of the valves 74a to 74c and the adjustment of the opening are controlled by the controller 100.

One end of each of the second pipes 75d to 75f is connected to one of the valves 74a to 74c, and the other end of the second pipe 75d to the upper end of the second suction hole 34d to 34f (the portion facing the wafer W). ) Has been reached. That is, the second pipe 75d extends so as to connect the valve 74a and the upper end of the second suction hole 34d, and the second pipe 75e extends so as to connect the valve 74b and the upper end of the second suction hole 34e. The second pipe 75f extends so as to communicate the upper end of the valve 74c and the second suction hole 34f. The second pipes 75d to 75f have the other ends extending only to the entrances (lower ends) of the second suction holes 34d to 34f (the second pipes 75d to 75f pass through the second suction holes 34d to 34f). Configuration).

As shown in FIGS. 4 and 5, the controller 100 includes, as functional modules, a chamber opening / closing control unit 101, a support pin elevating control unit 102, a plate movement control unit 103, a pressure determination unit 104, and a warp estimating unit. 105 and a valve control unit 106.

The chamber opening / closing control unit 101 controls the elevating mechanism 33 so that the chamber is opened / closed by elevating the top plate 32.

The support pin elevating control unit 102 controls the elevating mechanism 36 so that the wafer W is transferred between the temperature adjustment plate 51 and the support pins 35 by elevating the support pins 35. Further, the support pin elevating control unit 102 controls the elevating mechanism 36 so that the support pins 35 supporting the wafer W are lowered and the wafer W is placed on the hot plate 34 from the support pins 35. Further, the support pin elevating control unit 102 controls the elevating amount and elevating speed of the elevating mechanism 36 based on the warp information of the wafer W estimated by the warp estimating unit 105 described later. For example, the support pin elevating control unit 102 controls the elevating amount of the elevating mechanism 36 so that the warp information of the wafer W is acquired in advance so that the seating position on the hot plate 34 is appropriate.

The plate movement control unit 103 controls the drive mechanism 53 so that the temperature adjustment plate 51 moves inside the housing 90.

The pressure determination unit 104 acquires from the pressure sensors 73a to 73c the pressure values in the suction unit 70 (specifically, the first pipes 72a to 72c) that change as the wafer W approaches the hot plate 34, and changes the pressure. It is determined whether the amount has reached a predetermined value or more. The determination by the pressure determination unit 104 is performed when the process of estimating the warpage information of the wafer W is performed. When the determination by the pressure determination unit 104 is performed, the wafer W is suctioned by the valve control unit 106 described later through the second pipes 75d to 75f passing through the second suction holes 34d to 34f. , Valves 74a to 74c are controlled.

FIG. 7 shows an example of the determination of the amount of pressure change for each of the second suction holes 34d to 34f, where the horizontal axis represents the descending distance (1 / height) of the wafer W and the vertical axis represents the acquired pressure. ing. In the example shown in FIG. 7, suction starts when the descending distance reaches a predetermined value (VAC-on in FIG. 7), and thereafter the pressure change amount is small for a while (the pressure is close to “−20 kPa”). Is constant). In this state, the pressure determination unit 104 does not determine that “the pressure change amount has become equal to or more than the predetermined value”. Thereafter, when the wafer W further descends, the pressure value greatly changes at a certain timing. Therefore, at this timing, the pressure determination unit 104 determines that “the pressure change amount has become equal to or more than a predetermined value”. In the example shown in FIG. 7, at the stage where the descending distance is the shortest, the pressure change amount becomes equal to or more than a predetermined value in the first pipe 72a corresponding to the second suction hole 34d. In the first pipe 72b corresponding to the hole 34e, the pressure change amount becomes equal to or more than a predetermined value, and at the stage where the descending distance is the largest, the pressure change amount becomes equal to or more than the predetermined value in the first pipe 72c corresponding to the second suction hole 34f. I have. The location where the pressure value greatly changes (the location where the pressure variation is equal to or more than a predetermined value) indicates that the area of the corresponding wafer W is close to the measured second suction holes 34d to 34f. Therefore, it is possible to specify which region of the wafer W is likely to approach the hot plate 34 (that is, whether the region is concave in the direction of the hot plate 34) by the determination of the pressure determining unit 104.

The warpage estimating unit 105 estimates warpage information of the wafer W based on the determination result of the pressure determining unit 104. The warp estimating unit 105 acquires the height information of the wafer W from the elevating mechanism 36 when the pressure determining unit 104 determines that the pressure change amount is equal to or more than the predetermined value, and based on the height information, The amount of warpage of W is estimated. For example, the warp estimating unit 105 acquires height information (normal height information) of the flat wafer W when the pressure change amount becomes equal to or more than a predetermined value, and obtains the normal height. By comparing the information with the information, the amount of warpage of the warp estimation target area on the wafer W is estimated. For example, in the example shown in FIG. 7, when it is determined that the pressure change amount of the first pipe 72b corresponding to the second suction hole 34e is equal to or more than a predetermined value, the warp estimating unit 105 sends the pressure change The height information of the wafer W at the timing when the amount becomes equal to or more than the predetermined value is acquired. Then, the warp estimating unit 105 compares the acquired height information with the above-described normal height information, so that the area of the wafer W corresponding to the second suction hole 34e is compared with the flat wafer W. It is possible to estimate how much concave (or how much protruding), that is, how much warpage.

In addition, the warp estimating unit 105 determines whether or not the pressure change amounts of the pressure sensors 73a to 73c of the first pipes 72a to 72c corresponding to the plurality of second suction holes 34d to 34f are different from each other at different timings. , The warp shape of the wafer W is estimated. For example, in the example shown in FIG. 7, when the descending distance of the wafer W gradually increases (the wafer W approaches the hot plate 34), the first pipe corresponding to the second suction hole 34d at the stage where the descending distance is shortest. At the stage where the pressure change amount becomes equal to or more than the predetermined value at 72a and the next descent distance is short, at the stage where the pressure change amount becomes equal to or more than the predetermined value in the first pipe 72b corresponding to the second suction hole 34e and the descent distance is the longest, The amount of pressure change in the first pipe 72c corresponding to the second suction hole 34f is equal to or greater than a predetermined value. In such a case, the warp estimating unit 105 determines that the area of the wafer W corresponding to the central second suction hole 34d shown in FIG. It can be estimated that the region of the wafer W corresponding to the suction holes 34f is the furthest away from the hot plate 34, that is, the wafer W having a concave shape that is concave toward the center.

The valve control unit 106 controls the valves 74a to 74c so that the suction force is applied to a plurality of regions on the back surface of the wafer W. The valve control unit 106 performs a warp estimation control which is a control relating to an estimation of the warp information of the wafer W, and a suction control which is a control for correcting the warp of the wafer W and adsorbing the wafer W to the hot plate 34 after the warp estimation control. Do. When performing the warpage estimation control, the valve control unit 106 sets the suction amount to be smaller than when performing the suction control, and specifically, the suction amount is such that the warp correction of the wafer W is not performed. Next, the openings of the valves 74a to 74c are adjusted. After estimating the amount of warpage of the wafer W in the warpage estimation control, the valve control unit 106 controls the suction unit 70 so as to increase the volume of the suction unit 70. That is, for example, in the warpage estimation control, the valve control unit 106 controls the valve 74a so that the gas in the processing chamber 21 is sucked through the second pipes 75d to 75f corresponding to the second suction holes 34d to 34f. In addition to adjusting the suction pressure of the first suction holes 34a to 34c, the first suction holes 34a to 34c having a larger diameter than the second suction holes 34d to 34f are used in the suction control. The valves 74a to 74c are adjusted so that the gas is sucked. Thus, the volume of the suction unit 70 can be increased after the amount of warpage of the wafer W is estimated. Further, after the warpage estimation control, the valve control unit 106 may increase the volume of the suction unit 70 by, for example, switching the path to a pipe larger than that at the time of the warpage estimation control.

When performing the warpage estimation control, the valve control unit 106 controls the valves 74a to 74c so that the gas in the processing chamber 21 is sucked through the second pipes 75d to 75f corresponding to the second suction holes 34d to 34f. Adjust The valve control unit 106 first performs rough estimation control (first control) as warpage estimation control, and thereafter performs main estimation control (second control). In the rough estimation control, the valve control unit 106 determines, of the second pipes 75d to 75f corresponding to the plurality of second suction holes 34d to 34f, two or more second pipes 75d to 75f that do not cause mutual interference of the suction force. The valves 74a to 74c are controlled so that the suction force is applied to each group consisting of. In the rough estimation control, for example, the valve control unit 106 controls the two second pipes 75d to 75f (for which the corresponding second suction holes 34d to 34f are adjacent to each other) to apply a suction force to mutually adjacent regions on the back surface of the wafer W. The second pipes 75d to 75f) are different groups from each other. In the present estimation control, the valve control unit 106 controls the valves 74a to 74c such that the second pipes 75d to 75f corresponding to the plurality of second suction holes 34d to 34f respectively apply the suction force at different timings. I do. That is, in the present estimation control, only one of the plurality of valves 74a to 74c is opened, and the other valves are closed.

When performing the suction control, the valve control unit 106 determines the timing of suction through the first pipes 72a to 72c corresponding to the plurality of first suction holes 34a to 34c based on the estimation result of the warpage information by the warp estimation unit 105. Is determined, and the valves 74a to 74c are controlled so as to apply the suction force at the determined suction timing. For example, it is assumed that the warp estimation unit 105 determines that the wafer W has a concave shape that is concave toward the center as in the example illustrated in FIG. In this case, the valve control unit 106 controls the valves 74a to 74c such that the suction force is applied by the suction unit 70 in order from the region of the wafer W where the distance to the hot plate 34 is short. That is, the valve control unit 106 first controls the valves 74a to 74c so that the gas is sucked only from the first pipe 72a corresponding to the first suction hole 34a at the center where the distance to the hot plate 34 is the shortest. (Only the valve 74a is open; the valves 74b and 74c are closed), and then the first pipe corresponding to the first suction hole 34b outside the first suction hole 34a, which has the next shorter distance to the hot plate 34. The valves 74a to 74c are controlled so that the gas is also sucked from the valve 72b (the valves 74a and 74b are open and the valve 74c is closed). The valves 74a to 74c are controlled so that the gas is also sucked from the first pipe 72c corresponding to the first suction hole 34c outside the suction hole 34b (the valves 74a to 74c are opened).

When performing the suction control, the valve control unit 106 suctions the suction through the first pipes 72a to 72c corresponding to the plurality of first suction holes 34a to 34c based on the estimation result of the warpage information by the warp estimation unit 105. The amount is determined, and the valves 74a to 74c are controlled so as to apply the suction force with the determined suction amount. For example, it is assumed that the warp estimation unit 105 determines that the wafer W has a concave shape that is concave toward the center as in the example supported in FIG. In this case, the valve control unit 106 adjusts the opening of the valves 74a to 74c so that the suction amount of the suction by the suction unit 70 increases as the distance between the wafer W and the hot plate 34 increases. That is, the valve control unit 106 determines that the distance from the heating plate 34 is the longest, the suction amount in the first pipe 72a corresponding to the first suction hole 34a is the largest, and the distance from the heating plate 34 is the next longest. The suction amount in the first pipe 75b corresponding to the one suction hole 34b becomes the next largest, and the suction amount in the first pipe 75c corresponding to the first suction hole 34c, which has the shortest distance to the hot plate 34, becomes the smallest. Next, the openings of the valves 74a to 74c are adjusted.

The controller 100 is constituted by one or a plurality of control computers. For example, the controller 100 has a circuit 120 shown in FIG. The circuit 120 includes one or more processors 121, a memory 122, a storage 123, an input / output port 124, and a timer 125.

(4) The input / output port 124 inputs and outputs electric signals between the lifting mechanism 33, the lifting mechanism 36, the driving mechanism 53, the pressure sensors 73a to 73c, and the valves 74a to 74c. The timer 125 measures the elapsed time by counting, for example, a reference pulse having a constant period. The storage 123 has a computer-readable recording medium such as a hard disk. The recording medium records a program for executing a substrate processing procedure described later. The recording medium may be a removable medium such as a nonvolatile semiconductor memory, a magnetic disk, and an optical disk. The memory 122 temporarily stores the program loaded from the storage medium of the storage 123 and the calculation result by the processor 121. The processor 121 executes the above-described program in cooperation with the memory 122 to configure the above-described functional modules.

The hardware configuration of the controller 100 is not necessarily limited to a configuration in which each functional module is configured by a program. For example, each functional module of the controller 100 may be configured by a dedicated logic circuit or an ASIC (Application \ Specific \ Integrated \ Circuit) in which the logic circuit is integrated.

[Substrate processing procedure]
Next, as an example of the substrate processing method, a substrate processing procedure executed by the heat treatment unit U2 under the control of the controller 100 will be described with reference to FIGS.

フ ロ ー チ ャ ー ト The flowchart of FIG. 9 shows the processing procedure of the warpage estimation control and the suction control after the warpage estimation control. As shown in FIG. 9, first, the controller 100 performs a rough estimation control (first control) in the warpage estimation control (step S1). Subsequently, the controller 100 performs main estimation control (second control) of the warpage estimation control (step S2). After the warpage estimation control, the controller 100 performs the suction control (Step S3). For example, when processing is performed in lot units, the processing of steps S1 and S2 (estimation processing) is performed only on the first wafer W, and only the suction control in step S3 is performed on subsequent wafers W. May be. Before performing the suction control (before step S3), the controller 100 may perform a process of correcting the amount of elevating and lowering the elevating mechanism 36 based on the warpage information of the wafer W. Hereinafter, the rough estimation control, the main estimation control, and the suction control will be described with reference to FIGS.

(Rough estimation procedure)
FIG. 10 is a flowchart showing the rough estimation process. As shown in FIG. 10, in the rough estimation control, the controller 100 first controls the lifting mechanism 36 so that the support pins 35 supporting the wafer W start to descend (Step S11), The valves 74a to 74c are controlled so that suction is started for each group (the group of the second pipes 74d to 75f corresponding to the second suction holes 34d to 34f that simultaneously apply suction force) (step S12). The controller 100 controls the valves 74a to 74c so that the suction in the second pipes 75d to 75f belonging to different groups is not performed simultaneously.

Subsequently, the controller 100 acquires pressure values from the pressure sensors 73a to 73c (step S13), and determines whether there is a pressure value fluctuation (specifically, whether the pressure change amount is equal to or more than a predetermined value). (Step S14). If it is determined in S14 that there is no pressure value change, the process of S13 is performed again. On the other hand, when it is determined in S14 that there is a pressure value fluctuation, the controller 100 specifies the second suction holes 34d to 34f of the group determined to have the pressure value fluctuation, and The height information (position) of the wafer W at the timing when the pressure change amount becomes equal to or more than the predetermined value is acquired (Step S15). Subsequently, the controller 100 controls the elevating mechanism 36 so that the lowering of the support pin 35 is completed (step S16), and also controls the controller 100 via the second pipes 75d to 75f belonging to the group determined to have the pressure value fluctuation. The valves 74a to 74c are controlled so that the suction ends (step S17).

Subsequently, the controller 100 determines whether or not the determination of the change in the pressure value has been completed for all the groups (step S18). If it is determined in S18 that the processing has not been completed, the controller 100 executes the processing of S12 and subsequent steps again for each group before the determination of the pressure value fluctuation. On the other hand, if it is determined in S18 that the processing has been completed, the controller 100 estimates the warpage information of the wafer W based on the acquired height information (distance from the hot plate 34) of each region of the wafer W. (Step S19). In the rough estimation control, since the warpage information is estimated from the determination of the pressure value fluctuation in the group unit, the estimation system is inferior to the warpage information estimation in the main estimation described later.

(This estimation procedure)
FIG. 11 is a flowchart showing the present estimation processing. As shown in FIG. 11, in the present estimation control, the controller 100 controls the elevating mechanism 36 so that the support pins 35 supporting the wafer W are started to descend (step S31). The valves 74a to 74c are controlled so that suction is started for each of the second pipes 75d to 75f corresponding to the second suction holes 34d to 34f (step S33). The controller 100 controls the valves 74a to 74c so that the suction of the plurality of second suction holes 34d to 34f is not performed simultaneously.

Subsequently, the controller 100 acquires pressure values from the pressure sensors 73a to 73c (step S33), and determines whether there is a pressure value fluctuation (specifically, whether the pressure change amount is equal to or more than a predetermined value). (Step S34). If it is determined in S34 that there is no pressure value change, the process of S33 is performed again.

On the other hand, if it is determined in S34 that there is a pressure value fluctuation, the controller 100 controls the elevating mechanism 36 so that the lowering of the support pin 35 ends (step S35), and determines that there is a pressure fluctuation. The valves 74a to 74c are controlled such that the suction through the second pipes 75d to 75f corresponding to the second suction holes 34d to 34f is completed (step S36). Then, the controller 100 acquires, from the elevating mechanism 36, the height information (position) of the wafer W at the timing when the pressure change amount becomes equal to or more than the predetermined value (Step S37).

Subsequently, the controller 100 determines whether or not the determination of the change in the pressure value has been completed for all the second suction holes 34d to 34f (step S38). If it is determined in S38 that the process has not been completed, the controller 100 executes the processing of S31 and subsequent steps again for each of the second suction holes 34d to 34f before the determination of the pressure fluctuation. On the other hand, if it is determined in S38 that the processing has been completed, the controller 100 estimates the warpage information of the wafer W based on the acquired height information (distance from the hot plate 34) of each region of the wafer W. (Step S39).

In addition, the wafer W is usually supported by the support pins 35 in the central region. For this reason, when the wafer W is a convex-shaped wafer having a convex warp toward the center, it is possible to determine a pressure fluctuation (that is, obtain height information) for all the second suction holes 34d to 34f. . On the other hand, when the wafer W is a concave-shaped wafer that is recessed toward the center, the determination of the pressure fluctuation is not completed with respect to the outer peripheral region, and the wafer W is mounted on the hot plate 34. Can be considered. Even in this case, it is possible to estimate the warpage information that at least the wafer W is concave.

(Suction control procedure)
FIG. 12 is a flowchart showing the suction control process. As shown in FIG. 12, in the suction control, the controller 100 first acquires the warp information of the wafer W (Step S51). Subsequently, the controller 100 determines the order of performing the suction process and the suction amount for each of the first suction holes 34a to 34c based on the warp information (step S52). Specifically, the controller 100 determines the suction order based on the height information of each area of the wafer W so that the suction is performed in order from the area of the wafer W that is closer to the hot plate 34. Further, the controller 100 determines the suction amount based on the height information of each region of the wafer W such that the suction amount is larger in the region of the wafer W where the separation distance from the hot plate 34 is longer. Finally, the controller 100 controls the valves 74a to 74c so that the processing is performed in the determined suction order and suction amount.

(Function and effect)
In the conventional method, the process is performed without grasping the warpage information of the wafer W in advance. In this case, for example, as shown in FIG. 13, when processing a convex wafer W having a convex warp toward the center, if the wafer is a flat wafer, even if it is at a position that does not interfere with the temperature adjustment plate 51, The outer edge of the wafer W may interfere with the temperature adjustment plate 51 (see FIG. 13A). When the wafer W is placed on the hot plate 34, the lowering speed of the wafer W is usually reduced after the wafer W is sufficiently close to the hot plate 34. When a convex wafer W as shown in FIG. 13B is used, when the flat wafer W is used, the timing at which the normal lowering speed is set (that is, the wafer W does not approach the hot plate 34). Timing), the wafer W may reach the hot plate 34. In this case, the contact speed between the wafer W and the hot plate 34 increases, and the position of the wafer W on the hot plate 34 is shifted. There is a possibility that it will. As described above, when the process is performed without grasping the warp information of the wafer W, it may be difficult to perform an appropriate process similarly to a flat wafer. For this reason, it is required to grasp the warpage information of the wafer W in advance.

In this regard, the heat treatment unit U2 according to the present embodiment supports the hot plate 34 configured to mount the wafer W to be processed and the wafer W such that the wafer W is mounted on the hot plate 34. An elevating mechanism 36 configured to elevate and lower the support pins 35, a suction unit 70 for applying a suction force to a plurality of regions on the back surface of the wafer W so that the wafer W is attracted to the hot plate 34, A controller 100 for estimating warpage information of the wafer W based on a pressure change in each of the first pipes 72a to 72c of the suction unit 70 in response to the W approaching the hot plate 34.

In such a heat treatment unit U2, when the back surface of the wafer W is sucked by the suction unit 70 (the wafer W is sucked in the direction of the hot plate 34), the warpage of the wafer W based on the pressure change in the suction unit 70. Information is estimated. Here, when the wafer W has a warped shape, the timing at which the wafer W is placed on the hot plate 34 differs in each region. When a certain area of the wafer W approaches the hot plate 34, the pressure measured in the first pipes 72a to 72c for applying a suction force to the area changes. As described above, by detecting the pressure change in each of the first pipes 72a to 72c, it is possible to specify an area of the wafer W that is closer to the hot plate 34. By detecting such a pressure change for each of the first pipes 72a to 72c, it is possible to estimate unevenness information (warpage information) of the wafer W. In the heat treatment unit U2, such estimation of the warpage information of the wafer W can be easily performed using an existing configuration such as the suction unit 70 and the elevating mechanism 36. That is, according to the heat treatment unit U2, the warpage information of the wafer W can be easily estimated.

The elevating mechanism 36 elevates and lowers the wafer W so that the wafer W approaches the hot plate 34, and the controller 100 determines whether or not the amount of pressure change in the first pipes 72a to 72c is equal to or more than a predetermined value. When the pressure change amount becomes equal to or more than a predetermined value, height information of the wafer W is obtained from the elevating mechanism 36, and the warpage amount of the wafer W is estimated based on the height information. Thus, for example, when the separation distance between a certain area of the wafer W and the hot plate 34 is equal to or less than a predetermined distance, the height information of the wafer W is obtained, and the amount of warpage of the wafer W is estimated. By estimating the amount of warpage of the wafer W in this manner, warpage information of the wafer W can be estimated with higher accuracy.

The controller 100 estimates the warped shape of the wafer W according to the difference in the timing at which the pressure change amount becomes equal to or more than the predetermined value for each of the plurality of first pipes 72a to 72c. From the timing when the amount of pressure change becomes equal to or more than a predetermined value, that is, from the timing when the separation distance from the hot plate 34 becomes equal to or less than the predetermined distance, any region of the wafer W has a shape (concave shape) close to the hot plate 34. It is possible to specify which region of W has a shape (convex shape) far from the hot plate 34. For this reason, it is possible to highly accurately estimate the warped shape (which area is concave and which area is convex) of the wafer W by considering the difference in timing when the pressure change amount becomes equal to or more than a predetermined value. Can be.

The controller 100 performs main estimation control for controlling the valves 74a to 74c such that the second pipes 75d to 75f corresponding to the plurality of second suction holes 34d to 34f respectively apply suction at different timings, Prior to this estimation control, each of the second pipes 75d to 75f corresponding to the plurality of second suction holes 34d to 34f is grouped by two or more second pipes 75d to 75f that do not cause mutual interference of the suction force. And rough estimation control for controlling the valves 74a to 74c. For the second pipes 75d to 75f, suction force is applied at different timings in principle from the viewpoint of preventing mutual interference (performing the present estimation control). On the other hand, such control alone may require a long time for warpage estimation. In this regard, prior to this estimation control, the suction force is applied to each group of two or more second pipes 75d to 75f that do not interfere with each other (the rough estimation control is performed). Rough warpage information can be estimated before the main estimation control, while preventing mutual interference of suction forces. By performing the main estimation control (detailed estimation) after obtaining the rough warpage information, it is possible to shorten the estimation time and improve the accuracy.

(4) In the rough estimation control, the controller 100 sets the two second pipes 75d to 75f that apply suction force to regions adjacent to each other on the back surface of the wafer W as different groups. As a result, mutual interference of suction forces can be effectively prevented.

The controller 100 determines the suction timing of each of the plurality of second pipes 75d to 75f based on the warp information of the wafer W, and applies the suction force to the plurality of valves 74a to 74c so as to apply the suction force at the determined suction timing. Control. By applying the suction force by each of the second pipes 75d to 75f at a timing according to the warp information, the suction force is sequentially applied from the second pipes 75d to 75f corresponding to the area where the distance to the hot plate 34 is short. Becomes possible. For example, as shown in FIG. 14, when the application of the suction force is started from the suction unit corresponding to the region far from the hot plate 34, the outer edge portion is in a vacuum emptying state, and the suction at the time of suction is performed. There are problems that the suction completion time increases due to variations in the wafer attitude, and that the atmosphere flows in from the outer periphery of the wafer W and the wafer W temperature in-plane uniformity decreases. In this regard, as in the present embodiment, the suction force is sequentially applied from the second pipes 75d to 75f corresponding to the region where the distance to the hot plate 34 is short, thereby causing the above-described problem such as the emptying. Thus, the wafer W can be quickly and appropriately sucked.

The controller 100 determines the suction amount of each of the plurality of second pipes 75d to 75f based on the warpage information of the wafer W, and applies the suction force to the plurality of valves 74a to 74c so as to apply the suction force with the determined suction amount. Control. Thus, for example, it is possible to increase the suction force in a region farther from the hot plate 34, and it is possible to appropriately perform the suction (warp correction) of the substrate.

The raising / lowering mechanism 36 raises / lowers the wafer W so that the wafer W approaches the hot plate 34, and the controller 100 determines at least one of the raising / lowering amount and the raising / lowering speed of the raising / lowering mechanism 36 based on the warp information of the wafer W. Control. When a wafer W having a warped shape is transferred between the elevating mechanism 36 and the temperature adjustment plate 51 as in a normal wafer W, the temperature adjustment plate 51 and the wafer W may interfere with each other. Can be a problem. Further, when the wafer W having the warped shape is placed on the hot plate 34 from the elevating mechanism 36 similarly to the normal wafer W, when the normal wafer W is placed on the hot plate 34, However, even in a state where the vertical speed is increased, the warped wafer W may come into contact with the hot plate 34, which may cause a problem that the contact speed of the wafer W with the hot plate 34 increases. In this regard, by controlling (correcting) the elevating amount and the elevating speed of the elevating mechanism 36 based on the warp information of the wafer W, it is possible to suppress the above-described problem from occurring.

[Second embodiment]
Hereinafter, the second embodiment will be described with reference to FIGS. In the description of the second embodiment, differences from the first embodiment will be mainly described, and the same description as in the first embodiment will be omitted.

As shown in FIG. 15, in the heat treatment unit according to the second embodiment, the temperature control unit 110 of the controller 100 controls the temperature of the wafer W based on warpage information (clearance between each area of the wafer W and the hot plate 34). The temperature distribution in the hot plate 34 is adjusted. The heating plate 34 is a multi-channel heating plate, and the heaters 134a to 134d are divided for each area. That is, a heater 134a is provided at the center of the heating plate 34, a heater 134b is provided outside the heater 134a, a heater 134c is provided outside the heater 134b, and an outside of the heater 134c is provided. Is provided with a heater 134d. Further, temperature sensors 125a to 125d are provided as temperature sensors for measuring the temperatures of the respective regions of the heating plate 34 which are heated by the heaters 134a to 134d.

In the case where a concave wafer W that is concave toward the center is used as in the example illustrated in FIG. 15, for example, the temperature control unit 110 first acquires warpage information of the wafer W. Then, the temperature control unit 110 controls the heater so that the output of the heater becomes larger (the set temperature becomes higher) in a region closer to the outer end farther from the heating plate 34 so that the temperature distribution in the heating plate 34 becomes uniform. And the heaters 134a to 134d. That is, the temperature control unit 110 controls the heaters 134a to 134d such that the output increases in the order of the heater 134d, the heater 134c, the heater 134b, and the heater 134a. The temperature control unit 110 may adjust the outputs of the heaters 134a to 134d based on the temperatures measured by the temperature sensors 125a to 125d.

FIG. 16 is a graph showing the hot plate temperature behavior of a flat wafer W and a warped wafer W having a warped shape, in which the vertical axis indicates temperature, the horizontal axis indicates time, the solid line indicates the behavior of the flat wafer W, and the broken line. Shows the behavior of the wafer W having a warped shape. As shown in FIG. 16, the wafer W having a warped shape has a different heating plate temperature behavior from the flat wafer W because the distance from the hot plate 34 is not uniform and the amount of warpage changes during processing. ing. As a result, the wafer W having a warped shape may cause an overshoot, a failure to reach a set temperature, a rise in temperature due to heat storage, and the like, and a decrease in in-plane process performance of the wafer due to a reduction in in-plane uniformity of the wafer temperature. In addition, there may be a case where a variation in process performance within a lot when continuous processing is performed becomes a problem.

In this regard, as described above, the heaters 134a to 134d in the respective regions of the hot plate 34 are controlled by the temperature control unit 110 based on the warpage information of the wafer W, and the temperature distribution in the hot plate 34 is adjusted. Even if the wafer W has a warped shape and the distance between the wafer W and the hot plate 34 is not uniform, appropriately heating each region of the wafer W to suppress a decrease in process performance and the like. Can be.

Although the embodiment has been described above, the present disclosure is not limited to the embodiment. For example, it has been described that the wafer W is corrected by the suction unit 70 after estimating the warpage information of the wafer W. However, the present invention is not limited to this. The adverse effect of the warped wafer may be corrected by the temperature adjusting means described in the embodiment.

The aspect described in the present embodiment is not limited to being applied only to the heat treatment unit U2, but may be applied to other substrate processing apparatuses. In this case, a simple mounting portion may be used instead of the hot plate.

# 2: coating / developing device, 34: hot plate (mounting unit), 36: elevating mechanism (elevating unit), 70: suction unit, 100: controller, W: wafer (substrate).

Claims (12)

A mounting portion configured to mount a substrate to be processed,
An elevating unit configured to be able to elevate and lower at least one of the substrate and the mounting unit, so that the substrate is mounted on the mounting unit,
A plurality of suction units that apply suction force to a plurality of regions on the back surface of the substrate, so that the substrate is adsorbed to the mounting unit,
A substrate processing apparatus comprising: a control unit configured to estimate warpage information of the substrate based on a pressure change in each of the plurality of suction units in response to the substrate approaching the mounting unit. The lifting unit raises and lowers the substrate so as to bring the substrate closer to the mounting unit,
The control unit includes:
It is determined whether or not the pressure change amount of the suction unit is equal to or more than a predetermined value.If the pressure change amount is equal to or more than a predetermined value, height information of the substrate is obtained from the elevating unit, and based on the height information. The substrate processing apparatus according to claim 1, wherein the amount of warpage of the substrate is estimated using the method. The control unit includes:
The substrate processing apparatus according to claim 2, wherein a warped shape of the substrate is estimated according to a difference in timing at which the pressure change amount becomes equal to or more than a predetermined value for each of the plurality of suction units. The control unit includes:
A first control for controlling the plurality of suction units so that each of the plurality of suction units applies a suction force at a timing different from each other;
Prior to the first control, a second control for controlling the plurality of suction units is performed for each group of two or more suction units that do not cause mutual interference of suction forces among the plurality of suction units. The substrate processing apparatus according to claim 2. The control unit includes:
5. The substrate processing apparatus according to claim 4, wherein in the second control, two suction units that apply a suction force to regions adjacent to each other on the back surface of the substrate belong to different groups. (6) The substrate processing apparatus according to any one of (2) to (5), wherein the control unit controls the suction unit to increase the volume of the suction unit after estimating the amount of warpage of the substrate. The control unit includes:
The suction timing of each of the plurality of suction units is determined based on the warpage information of the substrate, and the plurality of suction units are controlled so as to apply a suction force at the determined suction timing. 7. The substrate processing apparatus according to claim 6. The control unit includes:
8. The suction amount of each of the plurality of suction units is determined based on the warpage information of the substrate, and the plurality of suction units are controlled so as to apply suction force with the determined suction amount. Substrate processing equipment. The placing section is a hot plate that heats the substrate,
The control unit includes:
The substrate processing apparatus according to any one of claims 1 to 8, wherein a temperature distribution in the hot plate is adjusted based on the warpage information of the substrate. The lifting unit raises and lowers the substrate so as to bring the substrate closer to the mounting unit,
The control unit includes:
10. The substrate processing apparatus according to claim 1, wherein at least one of a lifting amount and a lifting speed of the lifting unit is controlled based on the warpage information of the substrate. Applying suction force to a plurality of regions of the substrate placed on the placing portion,
A substrate processing method, comprising: estimating warpage information of the substrate based on a change in pressure according to the application of the suction force, which changes as the substrate approaches the mounting portion. A computer-readable storage medium storing a program for causing an apparatus to execute the substrate processing method according to claim 11.

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