Substrate processing apparatus and substrate processing method

Abstract

To provide a substrate processing device and a substrate processing method with which it is possible to improve the uniformity of etching on substrates.SOLUTION: A substrate processing device 100 comprises a first nozzle 141, a second nozzle 241, and a control unit 102. The first nozzle 141 supplies an etching liquid to the upper surface of a substrate W. The second nozzle 241 supplies a rinse liquid to the upper surface of the substrate W. The control unit 102 controls the supply of the etching liquid from the first nozzle 141 and the supply of the rinse liquid from the second nozzle 241. The control unit 102 causes the etching liquid to be discharged from the first nozzle 141 to at least a first region R1 of the substrate W. The control unit 102 causes the rinse liquid to be discharged from the second nozzle 241 toward a second region R2 which is different from the first region R1 in a radial direction RD, while the first nozzle 141 is discharging the etching liquid on the side inward from the second nozzle 241 in the radial direction RD of the substrate W.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method. [Background technology]

[0002] Conventionally, there has been known a substrate processing apparatus that processes the surface of a substrate such as a wafer by supplying an etching liquid to the surface of the substrate (see, for example, Patent Document 1). Patent Document 1 describes a single-wafer etching method that performs uniform etching by supplying the chemical liquid while moving a chemical liquid supply port from the outer periphery to the center of the wafer in a short time, prior to supplying the chemical liquid to the center of the wafer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 8-279485 Summary of the Invention [Problem to be solved by the invention]

[0004] As described in Patent Document 1, in a single-wafer etching method, when a chemical solution is supplied to a wafer, the chemical solution is supplied to a rotating wafer. Therefore, the chemical solution supplied to the wafer flows radially outward from the supply position. Therefore, the portion of the wafer radially outward from the supply position of the chemical solution is etched.

[0005] Here, as described in Patent Document 1, when a chemical solution is supplied to the center of a wafer, the amount of etching at the center is generally greater than that at the periphery of the wafer. In this case, it is possible to improve the uniformity of etching on the wafer by adjusting the movement speed of the chemical solution supply port.

[0006] However, depending on the type of film on the substrate surface and the type of chemical solution, even when the chemical solution is supplied to the center of the wafer, the amount of etching may be greater at the outer periphery of the wafer than at the center. In this case, it is difficult to improve the uniformity of etching on the wafer even if the movement speed of the chemical solution supply port is adjusted.

[0007] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a substrate processing apparatus and a substrate processing method that can improve the uniformity of etching on a substrate. [Means for solving the problem]

[0008] A substrate processing apparatus according to a first aspect of the present invention includes a substrate holding unit, a first nozzle, a second nozzle, a movement mechanism, and a control unit. The substrate holding unit holds a substrate horizontally and rotates the substrate about a rotation axis that passes through the center of the substrate and extends vertically. The first nozzle supplies an etching liquid to an upper surface of the substrate. The second nozzle supplies a rinse liquid to the upper surface of the substrate. The movement mechanism horizontally moves the first nozzle and the second nozzle. The control unit controls the supply of the etching liquid from the first nozzle, the supply of the rinse liquid from the second nozzle, and the movement mechanism. The control unit causes the first nozzle to eject the etching liquid toward at least a first region on the upper surface of the substrate. The control unit, when the first nozzle ejects the etching liquid radially inward of the second nozzle, causes the second nozzle to eject the rinse liquid toward a second region that is different from the first region in the radial direction.

[0009] In the substrate processing apparatus according to the first aspect of the present invention, the moving mechanism may include a first nozzle moving mechanism that moves the first nozzle horizontally above the substrate holding part, and a second nozzle moving mechanism that moves the second nozzle horizontally above the substrate holding part.

[0010] In the substrate processing apparatus according to the first aspect of the present invention, the control unit may cause the first nozzle to discharge the etching liquid onto the first region and the second region while moving the first nozzle in the radial direction.

[0011] In the substrate processing apparatus according to the first aspect of the present invention, the control unit may cause the second nozzle to eject the rinse liquid onto the second region without ejecting the rinse liquid onto the first region.

[0012] In the substrate processing apparatus according to the first aspect of the present invention, the substrate may have a plurality of regions in the radial direction. The plurality of regions may include a first specific region. The first specific region may be adjacent to the first region on the outside in the radial direction and may constitute the second region. While the first nozzle is discharging the etching liquid to a region radially inward of the first specific region, the second nozzle may discharge the rinse liquid to the first specific region for a first predetermined time.

[0013] In the substrate processing apparatus according to the first aspect of the present invention, the plurality of regions may further include a second specific region. The second specific region may be adjacent to the first specific region on the outside in the radial direction and may constitute the second region. While the first nozzle is discharging the etching liquid into the first region, the second nozzle may discharge the rinse liquid into the second specific region for a second predetermined time.

[0014] The substrate processing apparatus according to the first aspect of the present invention may further include a suction unit that suctions the etching liquid discharged from the first nozzle, and the control unit may cause the suction unit to suction the etching liquid in the second region when the first nozzle discharges the etching liquid at a position radially inward of the suction unit.

[0015] In the substrate processing apparatus according to the first aspect of the present invention, the control unit may acquire an etching rate of each region of the upper surface of the substrate when the etching liquid is discharged from the first nozzle, and may calculate a moving speed of the first nozzle and a discharge time of the rinse liquid from the second nozzle so that a product of the etching rate of each region in the radial direction of the upper surface of the substrate and a contact time of the etching liquid with each region is approximately constant.

[0016] The substrate processing apparatus according to the first aspect of the present invention may further include a measurement unit that measures a thickness distribution in a radial direction of the substrate. The control unit may control the measurement unit. The acquired etching rate may be calculated by measuring a thickness distribution in a radial direction of the substrate before and after the etching liquid is discharged from the first nozzle onto the upper surface of the substrate without discharging the rinse liquid from the second nozzle.

[0017] The substrate processing apparatus according to the first aspect of the present invention may further include a storage unit. The etching rate may be stored in the storage unit. The etching rate may be acquired by the control unit reading the etching rate from the storage unit. The control unit may calculate a movement speed of the first nozzle based on the etching rate in each of the regions, and move the first nozzle at the calculated movement speed.

[0018] A substrate processing method according to a second aspect of the present invention is a substrate processing method for etching a substrate. The substrate processing method includes the steps of holding the substrate horizontally by a substrate holder and rotating the substrate about a rotation axis passing through a center of the substrate, and discharging an etching solution from a first nozzle onto at least a first region of the substrate. In the step of discharging the etching solution from the first nozzle, while the first nozzle discharges the etching solution radially inward of the substrate relative to a second nozzle, a rinse solution is discharged from the second nozzle toward a second region radially different from the first region.

[0019] The substrate processing method according to a second aspect of the present invention may further include a step of acquiring an etching rate of each region when the etching liquid is discharged from the first nozzle onto the upper surface of the substrate without discharging the rinse liquid from the second nozzle.

[0020] The substrate processing method according to a second aspect of the present invention may further include a step of measuring a radial thickness distribution of the substrate before and after the etching solution is discharged from the first nozzle onto the upper surface of the substrate. The etching rate obtained in the obtaining step may be calculated from the thickness distribution measured in the measuring step.

[0021] The substrate processing method according to a second aspect of the present invention may further include a step of calculating a moving speed of the first nozzle and a discharging time of the rinse liquid from the second nozzle so that a product of the etching rate of each region in the radial direction of the upper surface of the substrate and a contact time of the etching liquid with each region becomes approximately constant. The substrate processing method may further include a step of calculating a movement speed of the first nozzle based on the etching rate in each region, and a step of moving the first nozzle at the calculated movement speed in the step of ejecting the etching liquid from the first nozzle.

[0022] In the substrate processing method according to the second aspect of the present invention, the second region may be a region in which a rate of change in the etching rate for the first nozzle becomes equal to or greater than zero outward in the radial direction.

[0023] A substrate processing apparatus according to a third aspect of the present invention includes a substrate holding unit, a first nozzle, an inhibition unit, and a control unit. The substrate holding unit holds a substrate and rotates the substrate. The first nozzle supplies an etching liquid to an upper surface of the substrate. The inhibition unit inhibits etching of the substrate by the etching liquid. The control unit controls the first nozzle and the inhibition unit. The control unit causes the first nozzle to eject the etching liquid onto the first substrate. The control unit calculates an etching rate at each position on the upper surface of the first substrate. The control unit calculates an inhibition condition for inhibiting etching by the etching liquid using the inhibition unit based on the calculation result of the etching rate. When the etching liquid is ejected from the first nozzle onto the upper surface of a second substrate different from the first substrate, the control unit controls the inhibition unit to inhibit the etching under the inhibition condition at positions on the upper surface of the second substrate where the rate of change of the etching rate toward the outside in the radial direction is equal to or greater than zero.

[0024] In the substrate processing apparatus according to a third aspect of the present invention, the inhibition unit may include a second nozzle that supplies a rinse liquid, and a nozzle movement mechanism that can move the second nozzle in a horizontal direction above the substrate holding unit. The inhibition of the etching by the inhibition unit may be performed by controlling the supply of rinse liquid from the second nozzle to the second substrate and by controlling the position of the second nozzle with respect to the second substrate by the control unit. The inhibition unit may include a suction unit that sucks the etching liquid discharged from the first nozzle and a suction movement mechanism that moves the suction unit in a horizontal direction. The inhibition of the etching by the inhibition unit may be performed by the suction unit sucking the etching liquid on the second substrate and by the control unit controlling the position of the suction unit relative to the second substrate.

[0025] A substrate processing method according to a fourth aspect of the present invention is a substrate processing method for a substrate processing apparatus including a substrate holding unit that holds and rotates a substrate, a first nozzle that supplies an etching solution to an upper surface of the substrate, and an inhibition unit that inhibits etching of the substrate by the etching solution. The substrate processing method includes the steps of: discharging the etching solution from the first nozzle onto a first substrate; acquiring an etching rate at each position on the upper surface of the first substrate; calculating an inhibition condition that inhibits etching by the etching solution based on the acquired etching rate; and discharging the etching solution from the first nozzle onto an upper surface of a second substrate different from the first substrate to process the second substrate. In the step of processing the second substrate, while the etching solution is being discharged from the first nozzle onto the upper surface of the second substrate, the inhibition unit inhibits the etching under the inhibition condition at positions on the upper surface of the second substrate where the rate of change of the etching rate toward the outside in the radial direction is equal to or greater than zero.

[0026] In the substrate processing method according to the fourth aspect of the present invention, the inhibition unit may have a second nozzle that supplies a rinse liquid, and the inhibition of the etching by the inhibition unit may be performed by supplying the rinse liquid from the second nozzle to the upper surface of the second substrate at a predetermined position based on the inhibition condition.

[0027] The substrate processing method according to a fourth aspect of the present invention may further include a step of measuring a radial thickness distribution of the first substrate before and after the etching liquid is discharged from the first nozzle onto the upper surface of the first substrate. [Effects of the Invention]

[0028] According to the present invention, it is possible to provide a substrate processing apparatus and a substrate processing method that can improve the uniformity of etching on a substrate. [Brief explanation of the drawings]

[0029] [Figure 1]1 is a schematic plan view showing a substrate processing apparatus according to an embodiment of the present invention; [Figure 2] 1 is a schematic cross-sectional view of a processing unit according to an embodiment of the present invention. [Figure 3] FIG. 2 is a plan view illustrating a scanning process according to an embodiment of the present invention. [Figure 4] FIG. 10 is a plan view illustrating a thickness measurement process according to an embodiment of the present invention. [Figure 5] FIG. 2 is a plan view showing the upper surface of the substrate. [Figure 6] 1 is a graph showing an example of an etching rate f(r) at each position in the radial direction of a substrate. [Figure 7] 10 is a graph showing an example of the distribution of thickness of a substrate when an etching liquid is discharged from a first nozzle onto the center of the substrate for a predetermined time without a rinse liquid being discharged from a second nozzle in a substrate processing apparatus according to one embodiment of the present invention. [Figure 8] 8 is a graph showing an example of the distribution of the thickness of the substrate when the first nozzle is moved from the state shown in FIG. 7 to an area A6 at a predetermined speed. [Figure 9] 8 is a graph showing an example of the distribution of thickness of the substrate when the first nozzle is moved from the state shown in FIG. 7 to an area A7 at a predetermined speed while the rinse liquid is being discharged from the second nozzle for a predetermined time. [Figure 10] 10 is a flowchart showing a method for calculating the scan speed of a first nozzle, and the discharge position and discharge time of a second nozzle in the substrate processing apparatus of one embodiment of the present invention. [Figure 11] 10 is a flowchart showing steps for measuring the thickness distribution of a substrate by the substrate processing apparatus of one embodiment of the present invention. [Figure 12] 10 is a flowchart showing steps for calculating a target scan speed of a first nozzle and a discharge time of a rinse liquid from a second nozzle in the substrate processing apparatus according to one embodiment of the present invention. [Figure 13] 3 is a flowchart showing a substrate processing method according to the present embodiment. [Figure 14] FIG. 10 is a plan view showing a structure around a first nozzle, a second nozzle, and a suction unit of a substrate processing apparatus according to a modified example of the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments, and can be implemented in various forms without departing from the spirit of the present invention. Note that where explanations are repeated, they may be omitted as appropriate. In addition, in the drawings, the same or equivalent parts are designated by the same reference numerals, and explanations will not be repeated.

[0031] A substrate processing apparatus 100 according to one embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a schematic diagram of the substrate processing apparatus 100 according to this embodiment. More specifically, Fig. 1 is a schematic plan view of the substrate processing apparatus 100. The substrate processing apparatus 100 is a single-wafer processing apparatus that processes substrates W one by one. In this embodiment, the substrates W are semiconductor wafers. The substrates W are generally disk-shaped.

[0032] As shown in FIG. 1, the substrate processing apparatus 100 includes a plurality of processing units 1, a fluid cabinet 100A, a plurality of fluid boxes 100B, a plurality of load ports LP, an indexer robot IR, a center robot CR, and a controller 101.

[0033] Each load port LP accommodates a stack of substrates W. The indexer robot IR transports the substrates W between the load port LP and the center robot CR. The center robot CR transports the substrates W between the indexer robot IR and the processing units 1. Each processing unit 1 supplies a processing liquid to the substrate W to process the substrate W. The fluid cabinet 100A accommodates the processing liquid.

[0034] The multiple processing units 1 form multiple towers TW (four towers TW in FIG. 1) arranged to surround the center robot CR in a plan view. Each tower TW includes multiple processing units 1 stacked vertically (three processing units 1 in FIG. 1). Each fluid box 100B corresponds to one of the multiple towers TW. The processing liquid in the fluid cabinet 100A is supplied to all processing units 1 included in the tower TW corresponding to the fluid box 100B via one of the fluid boxes 100B.

[0035] The controller 101 controls the operation of each part of the substrate processing apparatus 100. For example, the controller 101 controls the load port LP, the indexer robot IR, and the center robot CR.

[0036] Next, the processing unit 1 of this embodiment will be described with reference to Fig. 2. Fig. 2 is a schematic diagram of the processing unit 1 of this embodiment. More specifically, Fig. 2 is a schematic cross-sectional view of the processing unit 1.

[0037] As shown in FIG. 2, the processing unit 1 processes an object constituting a substrate W with a processing liquid. Hereinafter, the object to be processed with the processing liquid will be referred to as "object TG." The object TG is, for example, a substrate body (e.g., a substrate body made of silicon) or a substance formed on the surface of the substrate body. The substance formed on the surface of the substrate body is, for example, a substance made of the same material as the substrate body (e.g., a layer made of silicon) or a substance made of a different material from the substrate body (e.g., a silicon oxide film, a silicon nitride film, or a resist). The "substance" may form a film.

[0038] In this embodiment, the processing liquid includes an etching liquid, and the processing unit 1 performs an etching process. The target TG is processed (etched) by the etching liquid. The etching liquid is a chemical liquid. The etching liquid is, for example, hydrofluoric nitric acid (a mixture of hydrofluoric acid (HF) and nitric acid (HNO3)), hydrofluoric acid, buffered hydrofluoric acid (BHF), ammonium fluoride, HFEG (a mixture of hydrofluoric acid and ethylene glycol), or phosphoric acid (H3PO4).

[0039] The processing unit 1 includes a chamber 2, a spin chuck 3, a spin motor unit 5, a first nozzle movement mechanism 16, a second nozzle movement mechanism 26, multiple guards 10, a first nozzle 141, a second nozzle 241, a measurement unit 8, and a probe movement mechanism 9. The substrate processing apparatus 100 also includes an etching liquid supply unit 14 and a rinse liquid supply unit 24. The etching liquid supply unit 14 has a first supply pipe 142, and the rinse liquid supply unit 24 has a second supply pipe 242. The first nozzle movement mechanism 16 is an example of the "movement mechanism" of the present invention. The second nozzle movement mechanism 26 is an example of the "movement mechanism" and "nozzle movement mechanism" of the present invention. The second nozzle movement mechanism 26 and the rinse liquid supply unit 24 are an example of the "inhibition unit" of the present invention.

[0040] The chamber 2 has a generally box-like shape and accommodates the substrate W, the spin chuck 3, the spin motor unit 5, the first nozzle moving mechanism 16, the second nozzle moving mechanism 26, multiple guards 10, the first nozzle 141, the second nozzle 241, the measurement unit 8, the probe moving mechanism 9, part of the first supply pipe 142, and part of the second supply pipe 242.

[0041] The spin chuck 3 holds the substrate W horizontally. Specifically, the spin chuck 3 has a plurality of chuck members 32 and a spin base 33. The plurality of chuck members 32 are provided on the spin base 33 along the periphery of the substrate W. The plurality of chuck members 32 hold the substrate W in a horizontal position. The spin base 33 is substantially disk-shaped and supports the plurality of chuck members 32 in a horizontal position. The spin chuck 3 is an example of the "substrate holding portion" of the present invention.

[0042] The spin motor unit 5 rotates the substrate W and the spin chuck 3 together around a first rotation axis AX1. The first rotation axis AX1 extends in the vertical direction. In this embodiment, the first rotation axis AX1 passes through the center of the substrate W and extends in a substantially vertical direction. More specifically, the spin motor unit 5 rotates the spin base 33 around the first rotation axis AX1. Therefore, the spin base 33 rotates around the first rotation axis AX1. As a result, the substrate W held by the multiple chuck members 32 provided on the spin base 33 rotates around the first rotation axis AX1. The first rotation axis AX1 is an example of the "rotation axis" in the present invention.

[0043] Specifically, the spin motor unit 5 has a motor body 51, a shaft 53, and an encoder 55. The shaft 53 is coupled to the spin base 33. The motor body 51 rotates the shaft 53. As a result, the spin base 33 rotates.

[0044] The encoder 55 measures the rotation speed of the substrate W. The encoder 55 generates a signal indicating the rotation speed of the substrate W. More specifically, the encoder 55 generates a rotation speed signal indicating the rotation speed of the motor main body 51.

[0045] The first nozzle 141 supplies the etching liquid to the substrate W. More specifically, the first nozzle 141 ejects the etching liquid toward the rotating substrate W. The etching liquid supply unit 14 supplies the etching liquid to the first nozzle 141. More specifically, the first nozzle 141 is connected to one end of a first supply pipe 142. The etching liquid is supplied to the first nozzle 141 via the first supply pipe 142. The first supply pipe 142 is a tubular member through which the etching liquid flows.

[0046] The first nozzle moving mechanism 16 moves the first nozzle 141. In this embodiment, the first nozzle moving mechanism 16 moves the first nozzle 141 in the horizontal direction above the spin chuck 3. More specifically, the first nozzle moving mechanism 16 rotates the first nozzle 141 around a second rotation axis AX2 that is aligned in a substantially vertical direction. The first nozzle 141 discharges the etching liquid toward the substrate W while standing still or moving (while rotating). The first nozzle 141 is sometimes referred to as a scan nozzle.

[0047] Specifically, the first nozzle movement mechanism 16 has a nozzle arm 161, a first rotation shaft 163, and a first drive unit 165. The nozzle arm 161 extends in a substantially horizontal direction. The first nozzle 141 is disposed at the tip of the nozzle arm 161. The nozzle arm 161 is coupled to the first rotation shaft 163. The first rotation shaft 163 extends in a substantially vertical direction. The first drive unit 165 rotates the first rotation shaft 163 about the second rotation axis AX2, causing the nozzle arm 161 to rotate about the first rotation axis 163 along a substantially horizontal plane. As a result, the first nozzle 141 moves along the substantially horizontal plane. More specifically, the first nozzle 141 revolves around the first rotation shaft 163 about the second rotation axis AX2. The first drive unit 165 includes, for example, a stepping motor.

[0048] The rinse liquid supply unit 24 and the second nozzle movement mechanism 26 inhibit etching of the substrate W by the etching liquid. In this embodiment, etching is inhibited by diluting the etching liquid with the rinse liquid. Specifically, the second nozzle 241 supplies the rinse liquid to the substrate W. More specifically, the second nozzle 241 ejects the rinse liquid toward the rotating substrate W. The rinse liquid supply unit 24 supplies the rinse liquid to the second nozzle 241. More specifically, the second nozzle 241 is connected to one end of a second supply pipe 242. The rinse liquid is supplied to the second nozzle 241 through the second supply pipe 242. The second supply pipe 242 is a tubular member through which the rinse liquid flows. The rinse liquid is, for example, deionized water, carbonated water, electrolytic ionized water, hydrogen water, ozone water, or hydrochloric acid water with a diluted concentration (for example, about 10 ppm to 100 ppm). Note that a diluted etching liquid may be used as the rinse liquid.

[0049] The second nozzle moving mechanism 26 moves the second nozzle 241. In this embodiment, the second nozzle moving mechanism 26 moves the second nozzle 241 in the horizontal direction above the spin chuck 3. More specifically, the second nozzle moving mechanism 26 rotates the second nozzle 241 about a third rotation axis AX3 that is aligned in the substantially vertical direction. The second nozzle 241 discharges the rinse liquid toward the substrate W while remaining stationary. Note that the second nozzle 241 may discharge the rinse liquid while moving (while rotating).

[0050] The second nozzle movement mechanism 26 includes a nozzle arm 261, a second rotation shaft 263, and a second drive unit 265. The nozzle arm 261 extends in a substantially horizontal direction. The second nozzle 241 is disposed at the tip of the nozzle arm 261. The nozzle arm 261 is coupled to the second rotation shaft 263. The second rotation shaft 263 extends in a substantially vertical direction. The second drive unit 265 rotates the second rotation shaft 263 about a third rotation axis AX3, causing the nozzle arm 261 to rotate about the second rotation shaft 263 along a substantially horizontal plane. As a result, the second nozzle 241 moves along the substantially horizontal plane. Specifically, the second nozzle 241 revolves around the second rotation shaft 263 about the third rotation axis AX3. The second drive unit 265 includes, for example, a stepping motor.

[0051] Each of the guards 10 has a substantially cylindrical shape. The guards 10 receive the etching liquid and the rinsing liquid discharged from the substrate W.

[0052] The measurement unit 8 acquires information indicating the thickness distribution of the substrate W. In other words, the measurement unit 8 acquires information indicating the surface shape (profile) of the substrate W. In this embodiment, the measurement unit 8 measures the thickness distribution of the substrate W in the radial direction RD.

[0053] In this embodiment, the measurement unit 8 measures the thickness of the object TG in a non-contact manner and generates a thickness detection signal indicating the thickness of the object TG. The thickness detection signal is input to the control device 101.

[0054] The measurement unit 8 measures the thickness of the object TG by, for example, spectral interferometry. Specifically, the measurement unit 8 includes an optical probe 81, a signal line 83, and a measurement device 85. The optical probe 81 has a lens. The signal line 83 connects the optical probe 81 and the measurement device 85. The signal line 83 includes, for example, an optical fiber. The measurement device 85 has a light source and a light receiving element. Light emitted from the light source of the measurement device 85 is emitted to the object TG via the signal line 83 and the optical probe 81. Light reflected by the object TG is received by the light receiving element of the measurement device 85 via the optical probe 81 and the signal line 83. The measurement device 85 analyzes the light received by the light receiving element to calculate the thickness of the object TG. The measurement device 85 generates a thickness detection signal indicating the calculated thickness of the object TG. Note that the measurement method of the measurement unit 8 is not limited to spectral interferometry, and other measurement methods may be used as long as they can measure the thickness of the object TG.

[0055] The probe movement mechanism 9 moves the optical probe 81 in a substantially horizontal direction. More specifically, the probe movement mechanism 9 rotates the optical probe 81 around a fourth rotation axis AX4 that is aligned in a substantially vertical direction. While moving (rotating), the optical probe 81 emits light toward the substrate W. Therefore, the thickness detection signal indicates the thickness distribution of the target TG.

[0056] Specifically, the probe movement mechanism 9 has a probe arm 91, a third rotation shaft 93, and a third drive unit 95. The probe arm 91 extends in a substantially horizontal direction. The optical probe 81 is disposed at the tip of the probe arm 91. The probe arm 91 is coupled to the third rotation shaft 93. The third rotation shaft 93 extends in a substantially vertical direction. The third drive unit 95 rotates the third rotation shaft 93 about a fourth rotation axis AX4, causing the probe arm 91 to rotate about the third rotation axis 93 along a substantially horizontal plane. As a result, the optical probe 81 moves along the substantially horizontal plane. More specifically, the optical probe 81 revolves around the third rotation shaft 93 about the fourth rotation axis AX4. The third drive unit 95 includes, for example, a stepping motor.

[0057] In this embodiment, the measurement unit 8 is used to detect the etching amount. The etching amount indicates the amount of etching of the substrate W due to processing of the substrate W by the processing unit 1. More specifically, the measurement unit 8 acquires information indicating the thickness distribution of the substrate W before processing (the surface shape of the substrate W) (hereinafter referred to as pre-processing surface information) and information indicating the thickness distribution of the substrate W after processing (the surface shape of the substrate W) (hereinafter referred to as post-processing surface information). The etching amount can be calculated from the difference between the pre-processing surface information and the post-processing surface information.

[0058] The control device 101 acquires the etching amount by calculating the etching amount based on the thickness detection signal input from the measurement unit 8 (measurement device 85). More specifically, the control device 101 acquires the distribution of the etching amount. The control device 101 calculates the etching conditions using the acquired etching amount, as will be described later. The etching conditions include, for example, the movement speed of the first nozzle 141, and the position and time at which the rinse liquid is discharged from the second nozzle 241.

[0059] Furthermore, a rotation speed signal is input to the control device 101 from the encoder 55. The rotation speed of the substrate W during processing is, for example, constant. More specifically, the control device 101 stores a recipe for controlling each part of the substrate processing apparatus 100, and the recipe indicates a set value for the rotation speed of the motor main body 51. The control device 101 controls the processing performed by the processing unit 1 by referring to the recipe.

[0060] Next, the scanning process of the substrate W by the first nozzle 141 will be described with reference to FIG. 3. FIG. 3 is a plan view showing the scanning process of this embodiment. As shown in FIG. 3, the first nozzle 141 ejects the etching liquid onto the target TG while stopping or moving so that the landing position of the etching liquid on the surface of the target TG forms an arc-shaped trajectory TJ1. The trajectory TJ1 passes through the center CT of the substrate W. The center CT indicates the portion of the substrate W through which the first rotation axis AX1 passes. The scanning process is performed while the substrate W is rotating.

[0061] Furthermore, the second nozzle 241 ejects the rinse liquid onto the target TG while stopping or moving so that the landing position of the rinse liquid on the surface of the target TG forms an arc-shaped locus TJ2. In this embodiment, the locus TJ2 passes through the center CT of the substrate W. Note that the locus TJ2 does not have to pass through the center CT of the substrate W as long as it can pass near the center CT of the substrate W. The ejection of the rinse liquid is performed while the substrate W is rotating.

[0062] Next, the thickness measurement process by the measurement unit 8 will be described with reference to FIG. 4. FIG. 4 is a plan view showing the thickness measurement process of this embodiment. As shown in FIG. 4, the optical probe 81 of the measurement unit 8 measures the thickness of the object TG while moving so that the thickness measurement position for the object TG forms an arc-shaped trajectory TJ3. The trajectory TJ3 passes through the edge portion EG of the substrate W and the center portion CT of the substrate W. The edge portion EG indicates the peripheral portion of the substrate W. The thickness measurement process is performed while the substrate W is rotating.

[0063] Specifically, the optical probe 81 emits light toward the target TG while moving between the center CT and the edge EG of the substrate W in a plan view. As a result, the thickness of the target TG is measured at each measurement position included in the trajectory TJ2. Each measurement position corresponds to a radial position on the substrate W. Therefore, the thickness measurement process measures the thickness distribution of the target TG in the radial direction RD of the substrate W. Note that the surface shape (profile) of the target TG coincides with the shape indicating the thickness distribution of the target TG.

[0064] Next, the control device 101 will be described with reference to Fig. 1. As shown in Fig. 1, the control device 101 has a control unit 102, a storage unit 103, an input unit 104, and a display unit 105. The control device 101 is, for example, a computer. The control device 101 may be a general-purpose computer, or may be a computer with some of its components customized, or may be a computer designed specifically for the purpose.

[0065] The control unit 102 has a processor. The control unit 102 is, for example, a controller having a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). Alternatively, the control unit 102 may have a general-purpose computing machine or a dedicated computing machine. The control unit 102 may further have an NPU (Neural Network Processing Unit).

[0066] The memory unit 103 stores data and computer programs. The memory unit 103 has a main memory device. The main memory device is, for example, a semiconductor memory. The memory unit 103 may further have an auxiliary memory device. The auxiliary memory device is, for example, a semiconductor memory and / or a hard disk drive. The memory unit 103 may have removable media. The control unit 102 controls the operation of each unit of the substrate processing apparatus 100 based on the data and computer programs stored in the memory unit 103. Furthermore, the control unit 102 calculates etching conditions based on the data and computer programs stored in the memory unit 103. A detailed method for calculating the etching conditions will be described later.

[0067] The memory unit 103 stores a recipe and a control program. The recipe specifies the processing content and processing procedure for the substrate W. The recipe also indicates various setting values. The control unit 102 controls the operation of each unit of the substrate processing apparatus 100 based on the recipe and the control program.

[0068] The input unit 104 receives input from the worker and outputs information indicating the input result to the control unit 102. The input unit 104 includes, for example, a touch panel and a pointing device. The touch panel is, for example, disposed on the display surface of the display unit 105. The input unit 104 and the display unit 105 constitute, for example, a graphical user interface.

[0069] The display unit 105 displays various types of information. In this embodiment, the display unit 105 displays, for example, various error screens and various setting screens (input screens). The display unit 105 has, for example, a liquid crystal display or an organic EL (electroluminescence) display.

[0070] Next, with reference to FIG. 5 , the etching amount of the substrate W when the etching liquid is discharged from the first nozzle 141, assuming that no discharge from the second nozzle 241 occurs, will be described. In other words, the etching amount of the substrate W by the first nozzle 141, assuming that etching by the second nozzle 241 is not inhibited, will be described. FIG. 5 is a plan view showing the upper surface of the substrate W. Assuming that the etching liquid is discharged onto the rotating substrate W. In this case, the etching liquid flows radially outward from the landing position, etching the entire area radially outward from the landing position. Also, as a premise, even if the landing position of the etching liquid is changed, the etching rate at each position on the substrate W does not change. For example, whether the landing position of the etching liquid is set to the center CT of the substrate W or a position r [mm] away from the center CT of the substrate W, the etching rate at each position r [mm] or more away from the center CT of the substrate W is constant. The etching rate is the etching amount per unit time. According to the findings of the inventors of the present application, even if the landing position of the etching liquid is changed, the etching rate at each position on the substrate W hardly changes.

[0071] Here, the etching amount at a position r [mm] from the center CT of the substrate W is defined as F(r), the etching rate as f(r), and the scanning rate of the first nozzle 141 as v(r). The scanning rate is the moving rate of the first nozzle 141 during the scanning process. In this case, the etching amount F(r) at the position r [mm] is the product of the etching rate f(r) and the total contact time T [sec] of the etching liquid. The total contact time T [sec] of the etching liquid can be expressed as the following formula (1) using the scanning rate v(r). Note that the following formulas (1) to (3) relate to the etching liquid discharged from the first nozzle 141 and do not take into account the influence of the rinse liquid discharged from the second nozzle 241.

[0072]

number

[0073] Therefore, the etching amount F(r) at the position r [mm] is given by the following formula (2).

[0074]

number

[0075] In order to uniformly etch the upper surface of the substrate W, it is necessary to make dF(r) / dr=0. In other words, the following formula (3) must be satisfied.

[0076]

number

[0077] Here, as described above, when an etching liquid is supplied to the center of the substrate W, the amount of etching is generally greater at the center than at the outer periphery of the substrate W. In other words, the rate of change f'(r) of the etching rate is negative. In this case, by adjusting the scan speed v(r) when the first nozzle 141 is moved from the center of the substrate W toward the radially outward direction, it is possible to uniformly etch the top surface of the substrate W. In other words, it is possible to set the scan speed v(r) so that equation (3) holds.

[0078] On the other hand, when the etching liquid is supplied to the center of the substrate W, the amount of etching at the center may be smaller than that at the outer periphery of the substrate W. In other words, the rate of change f'(r) of the etching rate may be positive. In this case, simply adjusting the scan speed v(r) of the first nozzle 141 does not establish equation (3). In other words, it is generally not possible to uniformly etch the top surface of the substrate W. Therefore, in the present invention, the assumption that "the entire area radially outward from the position where the etching liquid is deposited is etched" is overturned, thereby achieving uniform etching of the top surface of the substrate W. This will be explained in detail below.

[0079] Next, with reference to FIGS. 6 to 8, a method for uniformly etching the upper surface of the substrate W even when the rate of change of the etching rate f'(r) is positive will be specifically described. FIG. 6 is a graph showing an example of the etching rate f(r) at each position in the radial direction RD of the substrate W. FIG. 6 is also a graph showing the distribution of the etching rate f(r) when the etching liquid is discharged from the first nozzle 141 toward the center of the substrate W without discharging the rinse liquid from the second nozzle 241. FIG. 7 is a graph showing an example of the thickness distribution of the substrate W when the etching liquid is discharged from the first nozzle 141 toward the center of the substrate W for a predetermined time without discharging the rinse liquid from the second nozzle 241. FIG. 8 is a graph showing an example of the thickness distribution of the substrate W when the first nozzle 141 is moved from the state shown in FIG. 7 to region A6 at a predetermined speed.

[0080] As shown in FIG. 6, the upper surface of the substrate W has, in the radial direction RD, a first region R1 and a second region R2 different from the first region R1. The first region R1 and the second region R2 have a circular or ring shape in a plan view. The first region R1 is a region where the rate of change f'(r) of the etching rate becomes negative toward the outside in the radial direction RD. The second region R2 is a region where the rate of change f'(r) of the etching rate becomes zero or greater toward the outside in the radial direction RD. In FIG. 6, the second region R2 is a region where the rate of change f'(r) of the etching rate becomes positive toward the outside in the radial direction RD.

[0081] The control unit 102 causes the first nozzle 141 to eject the etching liquid onto at least the first region R1 of the substrate W. In this embodiment, the control unit 102 causes the first nozzle 141 to eject the etching liquid onto the first region R1 and the second region R2 while moving the first nozzle 141 in the radial direction RD. Therefore, the etching liquid can be ejected more stably from the first nozzle 141 than in a case where, for example, ejection and non-ejection of the etching liquid are switched between the first region R1 and the second region R2.

[0082] When the etching solution is discharged from the first nozzle 141 onto the center portion (region A1) of the substrate W for a predetermined time, the thickness (surface shape) of the substrate W becomes as shown in Fig. 7. Then, by moving the first nozzle 141 outward in the radial direction RD from the state shown in Fig. 7 at a predetermined speed, the thickness of the first region R11 can be made uniform when the first nozzle 141 moves from the first region R11 to the second region R2, as shown in Fig. 8. However, as described using Fig. 6, the rate of change of the etching rate in the second region R2 is positive, so when the first nozzle 141 moves from the first region R11 to the second region R2, the thickness of the second region R2 becomes smaller than the thickness of the first region R11.

[0083] Therefore, in this embodiment, when the first nozzle 141 is discharging the etching solution inward in the radial direction RD from the second nozzle 241, the control unit 102 causes the second nozzle 241 to discharge the rinse solution into the second region R2. Specifically, when the first nozzle 141 is discharging the etching solution into the first region R11 shown in FIG. 6, the control unit 102 causes the second nozzle 241 to discharge the rinse solution into the second region R2. As a result, the first region R11 is etched, while the second region R2 and the first region R12 are not etched or etching is suppressed. In other words, etching of the second region R2 and the first region R12 by the etching solution is inhibited. Therefore, when the first nozzle 141 moves from the first region R11 to the second region R2, the etching amount of the second region R2 and the first region R12 can be made smaller or the same as the etching amount of the first region R11. 8, the thickness of the second region R2 can be made the same as or greater than the thickness of the first region R11. As a result, by adjusting the speed at which the first nozzle 141 moves through the second region R2, the amount or thickness of etching in the second region R2 can be made the same as the amount or thickness of etching in the first region R1. In other words, the top surface of the substrate W can be uniformly etched.

[0084] As described above, the second region R2 is a region where the rate of change f'(r) of the etching rate becomes equal to or greater than zero outward in the radial direction RD. Normally, when a region exists within the substrate W where the rate of change f'(r) of the etching rate becomes equal to or greater than zero, it is difficult to uniformly etch the upper surface of the substrate W simply by controlling the etching liquid using the first nozzle 141. However, by applying the present invention, it becomes possible to uniformly etch the upper surface of the substrate W.

[0085] Furthermore, the control unit 102 controls the second nozzle 241 to eject the rinse liquid onto the second region R2 without ejecting the rinse liquid onto the first region R1. Therefore, the rinse liquid can be selectively ejected onto the second region R2.

[0086] When etching the top surface of the substrate W, the first nozzle 141 may eject the etching liquid while moving from the center to the outer periphery of the substrate W, or may eject the etching liquid while moving from the outer periphery to the center of the substrate W. However, in this embodiment, for ease of understanding, an example will be described in which the first nozzle 141 ejects the etching liquid while moving from the center to the outer periphery of the substrate W.

[0087] Next, the discharge of the rinsing liquid will be described in more detail with reference to Figures 6 to 9. Figure 9 is a graph showing an example of the thickness distribution of the substrate W when the first nozzle 141 is moved at a predetermined speed to region A7 from the state shown in Figure 7 while discharging the rinsing liquid from the second nozzle 241 for a predetermined time. As shown in Figure 6, the upper surface of the substrate W is divided into a plurality of regions (here, A1 to A21) in the radial direction RD. In other words, the substrate W has a plurality of regions A1 to A21 in the radial direction. Each of the regions A1 to A21 has a circular or ring shape in plan view.

[0088] The multiple regions A1 to A21 include a first specific region Rs1. The first specific region Rs1 is adjacent to the first region R1 on the outer side in the radial direction RD and constitutes a second region R2. In Fig. 6, the first specific region Rs1 is region A7.

[0089] In this embodiment, while the first nozzle 141 is discharging the etching liquid into regions (here, A1 to A6) that are inward of the first specific region Rs1 in the radial direction RD, the second nozzle 241 discharges the rinse liquid into the first specific region Rs1 for a first predetermined time. Therefore, for example, when the first nozzle 141 moves from a region (here, A6) that is adjacent to the first specific region Rs1 on the inside in the radial direction RD to the first specific region Rs1, the etching amount of the first specific region Rs1 can be made smaller or equal to the etching amount of the region (here, A6) that is adjacent to the inside of the first specific region Rs1. In other words, as shown by the dashed line in FIG. 8, the thickness of the first specific region Rs1 can be made equal to or greater than the thickness of the regions A1 to A6. As a result, by adjusting the scanning speed at which the first nozzle 141 moves over the first specific region Rs1, the etching amount or thickness of the first specific region Rs1 can be made the same as the etching amount or thickness of the region (here, A6) adjacent to the inside of the first specific region Rs1.

[0090] The regions A1 to A21 further include a second specific region Rs2 that is adjacent to the first specific region Rs1 on the outer side in the radial direction RD and that constitutes the second region R2. In Fig. 6, the second specific region Rs2 is region A8.

[0091] Furthermore, in this embodiment, while the etching liquid is being discharged to the regions (here, A1 to A7) inside the second specific region Rs2 in the radial direction RD, the rinse liquid is discharged from the second nozzle 241 to the second specific region Rs2 for a second predetermined time. Therefore, for example, when the first nozzle 141 moves from the first specific region Rs1 to the second specific region Rs2, the etching amount of the second specific region Rs2 can be made smaller or equal to the etching amount of the first specific region Rs1. That is, as shown by the dashed line in FIG. 9 , the thickness of the second specific region Rs2 can be made equal to or greater than the thickness of the first specific region Rs1. As a result, by adjusting the speed at which the first nozzle 141 moves through the second specific region Rs2, the etching amount or thickness of the second specific region Rs2 can be made equal to the etching amount or thickness of the first specific region Rs1. In this embodiment, while the first nozzle 141 is discharging the etching liquid into the first region R11 (here, A1 to A6), the second nozzle 241 discharges the rinse liquid into the second specific region Rs2 for a second predetermined time.

[0092] 6, the rate of change f'(r) of the etching rate in the regions (A9 to A21 in this example) outside the second specific region Rs2 in the radial direction RD is negative. That is, when the first nozzle 141 moves from the second specific region Rs2 to the first region R12, the thickness of the first region R12 can be made greater than or equal to the thickness of the second specific region Rs2. Therefore, by adjusting the scan speed when the first nozzle 141 moves through the regions (A9 to A21 in this example) outside the second specific region Rs2, the etching amount in each region (A9 to A21 in this example) outside the second specific region Rs2 can be made the same as the etching amount in the second specific region Rs2.

[0093] As a result, it is possible to uniformly etch the entire upper surface of the substrate W. In other words, it is possible to make the etching amount the same in all regions (A1 to A21).

[0094] Next, a method for calculating the scan speed of the first nozzle 141, and the discharge position and discharge time of the second nozzle 241 will be specifically described with reference to Figs. 6 to 12 and Tables 1 and 2. Fig. 10 is a flowchart showing a method for calculating the scan speed of the first nozzle 141, and the discharge position and discharge time of the second nozzle 241 in the substrate processing apparatus 100 of this embodiment. Fig. 11 is a flowchart showing step S1 for measuring the thickness distribution of the substrate W using the substrate processing apparatus 100 of this embodiment. Fig. 12 is a flowchart showing step S6 for calculating the target scan speed of the first nozzle 141 and the discharge time of the rinse liquid from the second nozzle 241 in the substrate processing apparatus 100 of this embodiment.

[0095] The method of calculating the scan speed of the first nozzle 141 and the discharge position and discharge time of the second nozzle 241 in this embodiment includes steps S1 to S6. Furthermore, step S1 of measuring the thickness distribution of the substrate W includes steps S11 to S13. Furthermore, step S6 of calculating the target scan speed and the like of the first nozzle 141 includes steps S61 and S62. Steps S1 to S6 are executed by the control unit 102.

[0096] 10, in step S1, no rinse liquid is discharged from the second nozzle 241, and the thickness distribution in the radial direction RD of the substrate W is measured before and after the etching liquid is discharged onto the upper surface of the substrate W from the first nozzle 141. Specifically, in step S11 shown in FIG. 11, the measurement unit 8 is used to measure the thickness distribution of the target object TG in the radial direction RD of the substrate W. Hereinafter, the substrate W used in step S1 may be referred to as the "first substrate."

[0097] Next, in step S12, the etching liquid is discharged from the first nozzle 141 onto the center CT of the substrate W for a predetermined time without discharging a rinse liquid from the second nozzle 241, and then the discharge of the etching liquid is stopped. Note that the discharge time of the etching liquid is not particularly limited, but a longer discharge time can ensure a sufficient etching amount and therefore improve the measurement accuracy of the etching rate. In this embodiment, the etching liquid is discharged from the first nozzle 141 for, for example, 60 seconds.

[0098] Next, in step S13, the thickness distribution of the target object TG in the radial direction RD of the substrate W is measured using the measuring unit 8.

[0099] Next, in step S2, the etching rate of each region (each position) A1 to A21 in the radial direction RD of the substrate W is calculated. Specifically, the etching rate of each region A1 to A21 in the radial direction RD of the substrate W is calculated from the difference between the measurement result in step S11 and the measurement result in step S13. That is, the etching rate is calculated from the thickness distribution measured in step S1. As a result of the calculation in step S2, for example, the results shown in Table 1 below are obtained. That is, the etching rate at each position on the substrate W can be calculated. Table 1 shows an example of the etching rate calculated in step S2. The results shown in Table 1 correspond to the graph in FIG. 6.

[0100] [Table 1]

[0101] For ease of understanding, Table 1 shows an example in which measurements are taken at positions spaced 7.5 mm apart from the center CT (r=0) of the substrate W, and the etching rate changes in increments of approximately 0.5 nm or 1.0 nm, but the measurement intervals of the measuring unit 8 do not have to be equal, and the etching rate may be an irregular value with four or more decimal places. Here, the thickness of the target object TG is measured at one location in each of the regions A1 to A21.

[0102] Next, in step S3 (see FIG. 7), the etching rate calculated in step S2 is stored in the storage unit 103.

[0103] Next, in step S4, the etching rate is obtained in each of the regions (positions) A1 to A21 on the upper surface of the substrate W (first substrate). In other words, the etching rate is obtained in each of the regions A1 to A21 when the etching liquid is discharged from the first nozzle 141 without discharging the rinse liquid from the second nozzle 241 onto the upper surface of the substrate W.

[0104] Next, in step S5, a target etching solution contact time is calculated for each of the regions A1 to A21. Specifically, the target etching solution contact time is calculated for each of the regions A1 to A21 by dividing the target etching amount by the etching rate. Table 2 shows the etching rate, target etching solution contact time, target scan speed, etc. for each of the regions A1 to A21 of the substrate W.

[0105] [Table 2]

[0106] In the example shown in Table 2, the target etching amount in each of the regions A1 to A21 is 10 nm. Furthermore, since the etching rate in the region A1 is 0.5 nm / sec (=30.0 nm / min), the target etching solution contact time for the region A1 is 20 sec (=10 nm ÷ 0.5 nm / sec). Note that Table 2 shows the etching rate per second based on the etching rates in Table 1. In the same manner, the target etching solution contact times for the regions A2 to A21 are calculated.

[0107] In step S6, a target scan speed of the first nozzle 141 is calculated. First, in step S61 shown in Fig. 12, a difference in target etching liquid contact time is calculated. The difference in target etching liquid contact time indicates the difference between the target etching liquid contact time in a certain region and the target etching liquid contact time in the previous region (the region adjacent to the inside).

[0108] In the example shown in Table 2, the difference in target etching solution contact time in region A2 is the target etching solution contact time in region A2 minus the target etching solution contact time in region A1, which is 0.6897 sec (= 20.6897 sec - 20 sec). Similarly, the differences in target etching solution contact time in regions A3 to A21 are calculated.

[0109] 12, a target scan speed is calculated for each of the regions A2 to A21. In each of the regions A2 to A21, the moving distance of the first nozzle 141 is divided by the difference in the target etching liquid contact time to calculate the target scan speed.

[0110] In the example shown in Table 2, the movement distance of the first nozzle 141 from region A1 to region A2 is 7.5 mm. The difference in the target etching liquid contact time for region A2 is 0.6897 sec. If the first nozzle 141 moves 7.5 mm over a time of 0.6897 sec, the etching liquid contact time for region A2 will be 20.6897 sec. Therefore, the target scan speed of the first nozzle 141 from region A1 (r=0.0 mm) to region A2 (r=7.5 mm) is 10.875 mm / sec (=7.5 mm / 0.6897 sec). In a similar manner, the target scan speeds for regions A3 to A6 are calculated.

[0111] Here, the rate of change of the etching rate is positive in regions A7 and A8. That is, the etching rate in regions A7 and A8 is higher than that in regions A6 and A7, respectively, which are adjacent to the region A7. Therefore, for example, before the first nozzle 141 reaches region A7, the etching amount in region A7 becomes larger than the target etching amount. Similarly, before the first nozzle 141 reaches region A8, the etching amount in region A8 becomes larger than the target etching amount. In order to suppress the amount of etching solution discharged into regions A7 and A8, in this embodiment, the target scan speed in regions A7 and A8 is set to, for example, the upper limit of the set range.

[0112] Specifically, in the example shown in Table 2, the target scan speeds for regions A7 and A8 are calculated using the same formula as the scan speeds for regions A1 to A6, so both the target scan speeds for regions A7 and A8 are negative. In this embodiment, as described above, the target scan speeds for regions A7 and A8 are set to the upper limit of the setting range (e.g., 7500 mm / sec). Note that when the target scan speed is set to 7500 mm / sec, the time required to move 7.5 mm is 0.001 sec., so when the first nozzle 141 passes through region A7, region A7 is etched by 0.0004 nm (≈0.4417 nm / sec × 0.001 sec). Similarly, when the first nozzle 141 passes through region A8, region A8 is etched by 0.0004 nm. However, in this embodiment, for ease of understanding, the amount of etching of areas A7 and A8 when the first nozzle 141 passes through areas A7 and A8 at a scanning speed of 7500 mm / sec may be described as zero.

[0113] Furthermore, in order to achieve the target etching amounts in regions A7 and A8, the time during which regions A7 and A8 are in contact with the etching solution must be set to the target etching solution contact time. In this case, the time during which region A7 is in contact with the etching solution must be shorter than or equal to the time during which region A6 is in contact with the etching solution. Similarly, the time during which region A8 is in contact with the etching solution must be shorter than or equal to the time during which region A7 is in contact with the etching solution. Therefore, in this embodiment, as described above, the discharge position and discharge time of the second nozzle 241 are calculated so that, while the first nozzle 141 is discharging the etching solution to regions A1 to A6, the second nozzle 241 discharges the rinse solution to region A7 for a first predetermined time. Furthermore, the discharge position and discharge time of the second nozzle 241 are calculated so that, while the first nozzle 141 is discharging the etching solution to regions A1 to A7 (regions A1 to A6 in this embodiment), the second nozzle 241 discharges the rinse solution to region A8 for a second predetermined time. In addition, since the discharge of the rinse liquid from the second nozzle 241 inhibits etching by the etching liquid, calculating the discharge position and discharge time of the second nozzle 241 can be said to calculate the inhibiting conditions that inhibit etching by the etching liquid.

[0114] In the example shown in Table 2, the time that region A7 is in contact with the etching liquid needs to be 0.4354 seconds (=23.0769 seconds-22.6415 seconds) shorter than the time that region A6 is in contact with the etching liquid. Similarly, the time that region A8 is in contact with the etching liquid needs to be 0.4193 seconds (=22.6415-22.2222) shorter than the time that region A7 is in contact with the etching liquid. Therefore, the discharge position and discharge time (inhibition condition) of the second nozzle 241 are calculated so that the second nozzle 241 discharges the rinse liquid to region A7 for 0.4354 seconds (first predetermined time) while the first nozzle 141 discharges the etching liquid to regions A1 to A6. Furthermore, the discharge position and discharge time (inhibition condition) of the second nozzle 241 are calculated so that the second nozzle 241 discharges the rinse liquid into the region A8 for 0.4193 seconds (second predetermined time) while the first nozzle 141 discharges the etching liquid into the regions A1 to A7 (regions A1 to A6 in this embodiment). This makes it possible to make the etching amount uniform in the regions A1 to A8.

[0115] The first predetermined time may be set taking into consideration the time (0.0001 sec) it takes for the first nozzle 141 to pass through region A7. That is, the first predetermined time may be the sum of the difference in the target etching solution contact time (here, 0.4354 sec) and 0.0001 sec (the time it takes to pass through region A7). In this case, the etching amount in regions A1 to A7 can be made more uniform. Similarly, the second predetermined time may be set taking into consideration the time (0.0001 sec) it takes for the first nozzle 141 to pass through region A8. That is, the second predetermined time may be the sum of the difference in the target etching solution contact time (here, 0.4193 sec) and 0.0001 sec (the time it takes to pass through region A8). In this case, the etching amount in regions A1 to A8 can be made more uniform.

[0116] In the regions A9 to A21, the rate of change of the etching rate is negative, just like in the regions A2 to A6. Therefore, the target scan speed in the regions A9 to A21 is calculated in the same way as in the regions A2 to A6. This makes it possible to make the etching amount uniform over the entire upper surface of the substrate W.

[0117] In this embodiment, an example has been shown in which the discharge position and discharge time of the second nozzle 241 are calculated in step S62, but the present invention is not limited to this. For example, step S7 may be provided after step S6, and the discharge position and discharge time of the second nozzle 241 may be calculated in step S7.

[0118] Next, a substrate processing method executed by the substrate processing apparatus 100 will be described with reference to Figures 1, 2, and 13. Figure 13 is a flowchart showing the substrate processing method in this embodiment. In detail, Figure 13 shows the processing executed by the control unit 102 when etching the substrate W to be processed. The substrate processing method in this embodiment includes the processing of steps S1 to S6, step S101, and step S102. In other words, the substrate processing method in this embodiment includes a calculation flow for the scan speed of the first nozzle 141, and the discharge position and discharge time of the second nozzle 241.

[0119] 13 is started by an operator operating the input unit 104. When the operator inputs a start command, the control unit 102 executes the above-mentioned steps S1 to S6. As a result, the etching rate at each position on the substrate W is acquired, and the scan speed of the first nozzle 141 and the discharge position and discharge time of the second nozzle 241 are calculated. Note that in step S1, the thickness distribution is measured by discharging the etching liquid onto the first substrate.

[0120] Next, in step S101, the control unit 102 causes the spin chuck 3 to horizontally hold the substrate W to be processed and rotate the substrate W. Note that in steps S101 and S102, a second substrate different from the first substrate is used. Hereinafter, the substrate W used in steps S101 and S102 may be referred to as the "second substrate."

[0121] Next, in step S102, the substrate W (second substrate) is subjected to etching processing under the etching conditions calculated in steps S1 to S6.

[0122] Specifically, in this embodiment, the control unit 102 discharges the etching liquid from the first nozzle 141 toward the center CT of the substrate W for a predetermined time (e.g., 20 seconds). Then, the control unit 102 moves the first nozzle 141 from the center CT (area A1) of the substrate W toward the outer periphery at a target scan speed.

[0123] At this time, in this embodiment, while the first nozzle 141 is discharging the etching liquid into regions A1 to A6, the second nozzle 241 is discharging the rinse liquid into region A7 for a first predetermined time. Also, while the first nozzle 141 is discharging the etching liquid into regions A1 to A7 (regions A1 to A6 in this embodiment), the second nozzle 241 is discharging the rinse liquid into region A8 for a second predetermined time. Note that while the first nozzle 141 is discharging the etching liquid into regions A9 to A21, the second nozzle 241 is not discharging the rinse liquid.

[0124] Then, the control unit 102 stops the discharge of the etching liquid and stops the rotation of the substrate W.

[0125] An embodiment of the present invention has been described above with reference to FIGS. 1 to 13. In this embodiment, as described above, when the first nozzle 141 discharges the etching solution inward of the second nozzle 241 in the radial direction RD, the control unit 102 causes the second nozzle 241 to discharge the rinse solution into the second region R2. Specifically, when the first nozzle 141 discharges the etching solution into the first region R11 shown in FIG. 6, the control unit 102 causes the second nozzle 241 to discharge the rinse solution into the second region R2. As a result, the first region R11 is etched, while the second region R2 and the first region R12 are not etched or etching is suppressed. In other words, etching of the second region R2 and the first region R12 by the etching solution is inhibited. Therefore, when the first nozzle 141 moves from the first region R11 to the second region R2, the amount of etching of the second region R2 can be made smaller or the same as the amount of etching of the first region R11. As a result, by adjusting the speed at which the first nozzle 141 moves through the second region R2, the etching amount in the second region R2 and the etching amount in the first region R11 can be made the same, which means that the upper surface of the substrate W can be etched uniformly.

[0126] From another perspective, in this embodiment, as described above, the control unit 102 calculates the inhibition conditions (the discharge position and discharge time of the second nozzle 241) for inhibiting etching by the etching liquid using the inhibition unit (the rinse liquid supply unit 24 and the second nozzle movement mechanism 26) based on the calculation result of the etching rate. Furthermore, while processing the substrate W (second substrate) by discharging the etching liquid from the first nozzle 141 onto the upper surface of the substrate W, the control unit 102 controls the inhibition unit to inhibit etching under the inhibition conditions at positions on the upper surface of the substrate W where the rate of change of the etching rate outward in the radial direction RD is equal to or greater than zero. Therefore, etching by the etching liquid in the second region R2 can be inhibited. Therefore, when the first nozzle 141 moves from the first region R11 to the second region R2, the etching amount in the second region R2 can be made smaller or equal to the etching amount in the first region R11. As a result, by adjusting the speed at which the first nozzle 141 moves through the second region R2, the etching amount in the second region R2 and the etching amount in the first region R11 can be made the same, which means that the upper surface of the substrate W can be etched uniformly.

[0127] Furthermore, in this embodiment, as described above, the control unit 102 calculates the scan speed of the first nozzle 141 and the discharge time of the rinse liquid from the second nozzle 241 so that the product of the etching rate of each of the regions A1 to A21 in the radial direction RD of the upper surface of the substrate W and the time during which the etching liquid is in contact with each of the regions A1 to A21 becomes approximately constant. Therefore, the etching amount of each of the regions A1 to A21 can be easily made uniform.

[0128] Next, the structure of the substrate processing apparatus 100 according to a modification of the present embodiment will be described with reference to Fig. 14. Fig. 14 is a plan view showing the structure around the first nozzle 141, the second nozzle 241, and the suction unit 341 of the substrate processing apparatus 100 according to the modification of the present embodiment. In the modification shown in Fig. 14, an example will be described in which the substrate processing apparatus 100 further includes the suction unit 341, unlike the embodiment shown in Figs. 1 to 13.

[0129] As shown in FIG. 14 , in this modified example, the substrate processing apparatus 100 further includes a suction unit 341. The suction unit 341 sucks the etching liquid discharged from the first nozzle 141. Specifically, the substrate processing apparatus 100 includes the suction unit 341, a suction pipe 342, and a suction mechanism (not shown). The suction unit 341 is a suction nozzle. The suction unit 341 sucks the etching liquid discharged onto the substrate W. The suction unit 341 is connected to one end of the suction pipe 342. The etching liquid sucked by the suction unit 341 is discharged to the outside of the chamber 2 via the suction pipe 342. The suction mechanism (not shown) also creates a negative pressure inside the suction pipe 342.

[0130] The substrate processing apparatus 100 further includes a suction movement mechanism (not shown). The suction movement mechanism (not shown) is configured similarly to the first nozzle movement mechanism 16 or the second nozzle movement mechanism 26, for example, and rotates the suction part 341 along a substantially horizontal plane around a rotation axis (not shown).

[0131] The suction part 341, the suction mechanism, and the suction movement mechanism inhibit the etching of the substrate W by the etching liquid. The suction part 341, the suction mechanism, and the suction movement mechanism are examples of the "inhibition part" in the present invention.

[0132] The control unit 102 controls the suction mechanism and the suction movement mechanism. In this modification, when the first nozzle 141 discharges the etching liquid inward of the suction unit 341 in the radial direction RD, the control unit 102 causes the suction unit 341 to suck the etching liquid from the second region R2. Specifically, when the first nozzle 141 discharges the etching liquid from the first region R11 in FIG. 6, the control unit 102 causes the suction unit 341 to suck the etching liquid. As a result, the first region R11 is etched, while etching of the second region R2 and the first region R12 is suppressed. In other words, etching of the second region R2 and the first region R12 by the etching liquid is inhibited.

[0133] Furthermore, the control unit 102 calculates the inhibition condition for the suction unit 341 and controls the inhibition unit in accordance with the calculated inhibition condition. The inhibition condition for the suction unit 341 is the same as the inhibition condition for the second nozzle 241. Specifically, the suction unit 341 suctions the etching liquid in the region A7 at the same timing and for the same duration as the second nozzle 241 discharges the rinse liquid into the region A7. Furthermore, the suction unit 341 suctions the etching liquid in the region A8 at the same timing and for the same duration as the second nozzle 241 discharges the rinse liquid into the region A8.

[0134] In this modification, the suction unit 341 is disposed downstream of the first nozzle 141 and upstream of the second nozzle 241 in the rotation direction of the substrate W (counterclockwise in FIG. 14). Therefore, after the suction unit 341 reduces the etching liquid in the second region R2, the second nozzle 241 dilutes the etching liquid in the second region R2, thereby effectively inhibiting etching by the etching liquid.

[0135] The embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the above embodiments and can be implemented in various forms without departing from the spirit of the present invention. Furthermore, the components disclosed in the above embodiments can be modified as appropriate. For example, some of the components shown in one embodiment may be added to the components of another embodiment, or some of the components shown in one embodiment may be deleted from the embodiment.

[0136] The drawings mainly show each component in a schematic manner to facilitate understanding of the invention, and the thickness, length, number, spacing, etc. of each component shown in the drawings may differ from the actual ones due to the convenience of creating the drawings. Furthermore, the configuration of each component shown in the above embodiment is merely an example and is not particularly limited, and it goes without saying that various modifications are possible within a range that does not substantially deviate from the effects of the present invention.

[0137] 1 to 13, the substrate W is a semiconductor wafer, but the substrate W is not limited to a semiconductor wafer. For example, the substrate W may be a substrate for a liquid crystal display device, a substrate for a field emission display (FED), a substrate for an optical disk, a substrate for a magnetic disk, a substrate for a magneto-optical disk, a substrate for a photomask, a ceramic substrate, or a substrate for a solar cell.

[0138] 13, an example has been shown in which etching processing (steps S101 and S102) is performed on the substrate W after steps S1 to S6 have been performed, but the present invention is not limited to this. For example, a user or the like may manually perform calculations in steps S1 to S6 and input the etching conditions. Furthermore, the substrate processing apparatus 100 that performs steps S1 to S6 may be different from the substrate processing apparatus 100 that performs steps S101 and S102. In other words, etching processing may be performed using etching conditions calculated in another substrate processing apparatus 100.

[0139] In addition, in the above embodiment, an example has been shown in which the etching liquid is discharged while the first nozzle 141 is moved from the center toward the outer periphery of the substrate W, but the present invention is not limited to this. For example, the etching liquid may be discharged while the first nozzle 141 is moved from the outer periphery toward the center of the substrate W.

[0140] In the above embodiment, the first nozzle 141 and the second nozzle 241 are moved independently of each other, but the present invention is not limited to this. The first nozzle 141 and the second nozzle 241 may be moved integrally.

[0141] In the above embodiment, an example has been shown in which the first nozzle 141 scans the entire top surface of the substrate W, but the present invention is not limited to this. For example, the first nozzle 141 may scan a portion of the top surface of the substrate W excluding the central portion.

[0142] In the above embodiment, an example has been shown in which the rate of change in etching rate, the target etching liquid contact time, etc. are used when calculating the target scan speed, the discharge position, and the discharge time of the second nozzle 241, but the present invention is not limited to this. The rate of change in etching rate, the target etching liquid contact time, etc. do not have to be used when calculating the target scan speed, the discharge position, and the discharge time of the second nozzle 241.

[0143] Furthermore, in the above embodiment, for example, an example has been shown in which the scanning speed is increased when the first nozzle 141 passes through the region A7 and the region A8, but the present invention is not limited to this. The scanning speed does not have to be increased when the first nozzle 141 passes through the region A7 and the region A8. In this case, for example, the discharge of the etching liquid from the first nozzle 141 may be stopped. Also, for example, the time for which the rinse liquid is discharged from the second nozzle 241 may be longer than in the above embodiment by the time required for the first nozzle 141 to pass through the region A7 and the region A8.

[0144] Furthermore, in the modified example shown in FIG. 14, an example in which the second nozzle 241 and the suction part 341 are provided is shown, but of the second nozzle 241 and the suction part 341, only the suction part 341 may be provided.

[0145] In the above embodiment, examples of methods for inhibiting etching of the substrate W by the etching liquid have been described, such as discharging a rinse liquid or sucking the etching liquid, but the present invention is not limited to these. For example, etching by the etching liquid may be inhibited by partially lowering the temperature of the substrate W.

[0146] In the above embodiment, the substrate processing apparatus is described as including a control unit, a storage unit, an input unit, and a display unit, but the components of the present invention can be modified as appropriate in accordance with the spirit of the invention. For example, the present invention may be embodied in such a way that any or all of the storage unit, input unit, and display unit are separate from or located remotely from the control unit and can electrically communicate signals or information. [Industrial Applicability]

[0147] The present invention is useful in the field of substrate processing. [Explanation of symbols]

[0148] 3: Spin chuck (substrate holder) 16: First nozzle moving mechanism (moving mechanism) 24: Rinse liquid supply section (inhibition section) 26: Second nozzle movement mechanism (movement mechanism, nozzle movement mechanism, obstruction part) 100: Substrate processing apparatus 102: Control unit 141: First nozzle 241: Second nozzle 341: Suction part (inhibition part) A1~A21: Area AX1: First rotation axis (rotation axis) R2: 1st area R1: 2nd area R11: 1st area R12: 1st area RD: Radial direction Rs1: 1st specific area Rs2: 2nd specific area W: Substrate

Claims

1. a substrate holder that holds the substrate horizontally and rotates the substrate about a rotation axis that passes through the center of the substrate and extends vertically; a first nozzle for supplying an etching solution to an upper surface of the substrate; a second nozzle for supplying a rinse liquid to the upper surface of the substrate; a movement mechanism that horizontally moves the first nozzle and the second nozzle; a control unit that controls the supply of the etching liquid from the first nozzle, the supply of the rinse liquid from the second nozzle, and the movement mechanism; Equipped with The control unit The etching liquid is discharged from the first nozzle onto at least a first region on the upper surface of the substrate; acquiring an etching rate of each region in a radial direction of the substrate when the etching liquid is discharged from the first nozzle without discharging the rinse liquid from the second nozzle onto the upper surface of the substrate; a substrate processing apparatus configured to, when the first nozzle is discharging the etching liquid radially inward of the substrate relative to the second nozzle, discharge the rinse liquid from the second nozzle toward a second region that is different from the first region in the radial direction, toward the outside in the radial direction, and in which a rate of change of the etching rate for the first nozzle is equal to or greater than zero.

2. 2. The substrate processing apparatus of claim 1, wherein the moving mechanism includes a first nozzle moving mechanism that moves the first nozzle horizontally above the substrate holding portion, and a second nozzle moving mechanism that moves the second nozzle horizontally above the substrate holding portion.

3. 3 . The substrate processing apparatus according to claim 1 , wherein the control unit causes the first nozzle to eject the etching liquid onto the first region and the second region while moving the first nozzle in the radial direction.

4. The substrate processing apparatus according to claim 1 , wherein the control unit causes the second nozzle to eject the rinse liquid onto the second region without ejecting the rinse liquid onto the first region.

5. the substrate has a plurality of regions in the radial direction, the plurality of regions includes a first specific region that is adjacent to the first region on the outside in the radial direction and that constitutes the second region, 5. The substrate processing apparatus according to claim 1, wherein while the first nozzle is discharging the etching liquid into an area radially inward of the first specific area, the second nozzle is discharging the rinse liquid into the first specific area for a first predetermined time.

6. The plurality of regions further includes a second specific region that is adjacent to the first specific region on the outside in the radial direction and that constitutes the second region, The substrate processing apparatus according to claim 5 , wherein the rinsing liquid is discharged from the second nozzle to the second specific region for a second predetermined time while the first nozzle is discharging the etching liquid to the first region.

7. a suction unit that sucks the etching liquid discharged from the first nozzle, 7. The substrate processing apparatus according to claim 1, wherein the control unit causes the suction unit to suck the etching liquid from the second region when the first nozzle is discharging the etching liquid radially inward from the suction unit.

8. The control unit 8. The substrate processing apparatus according to claim 1, wherein the moving speed of the first nozzle and the ejection time of the rinse liquid from the second nozzle are calculated so that the product of the etching rate of each of the regions in the radial direction of the upper surface of the substrate and the time during which the etching liquid is in contact with each of the regions is approximately constant.

9. a measuring unit for measuring a thickness distribution in a radial direction of the substrate; The control unit controls the measurement unit, 9. The substrate processing apparatus according to claim 8, wherein the acquired etching rate is calculated by measuring a radial thickness distribution of the substrate before and after the etching liquid is discharged from the first nozzle onto the upper surface of the substrate without discharging the rinse liquid from the second nozzle.

10. Further comprising a storage unit, the etching rate is stored in the storage unit, 10. The substrate processing apparatus according to claim 8, wherein the etching rate is acquired by the control unit reading out the etching rate from the storage unit.

11. The control unit: calculating a moving speed of the first nozzle based on the etching rate in each of the regions; The substrate processing apparatus according to claim 1 , wherein the first nozzle is moved at the calculated moving speed.

12. A substrate processing method for etching a substrate, comprising: The substrate processing method includes: holding the substrate horizontally by a substrate holder and rotating the substrate about a rotation axis passing through the center of the substrate; Discharging an etching solution from a first nozzle onto at least a first region of the substrate; acquiring an etching rate of each region when the etching liquid is discharged from the first nozzle onto the upper surface of the substrate without discharging a rinse liquid from the second nozzle; and a second nozzle configured to discharge the rinsing liquid toward a second region, the second region being different from the first region in the radial direction and toward the outside in the radial direction, in which a rate of change of the etching rate for the first nozzle is equal to or greater than zero, while the first nozzle is discharging the rinsing liquid from the first nozzle toward a second region that is different from the first region in the radial direction and in which a rate of change of the etching rate for the first nozzle is equal to or greater than zero.

13. measuring a thickness distribution in a radial direction of the substrate before and after the etching liquid is discharged onto the upper surface of the substrate from the first nozzle; The substrate processing method according to claim 12 , wherein the etching rate obtained in the obtaining step is calculated from the thickness distribution measured in the measuring step.

14. 14. The substrate processing method according to claim 12, further comprising a step of calculating a moving speed of the first nozzle and a discharging time of the rinse liquid from the second nozzle so that a product of the etching rate of each region in the radial direction of the upper surface of the substrate and a contact time of the etching liquid with each region becomes approximately constant.

15. A process for calculating a moving speed of the first nozzle based on the etching rate in each of the regions; 15. The substrate processing method according to claim 12, further comprising: moving the first nozzle at the calculated moving speed in the step of discharging the etching liquid from the first nozzle.

16. a substrate holder that holds a substrate and rotates the substrate; a first nozzle for supplying an etching solution to an upper surface of the substrate; an inhibition portion that inhibits etching of the substrate by the etching solution; a control unit that controls the first nozzle and the inhibition unit; Equipped with The control unit The etching solution is discharged from the first nozzle onto the first substrate; Calculating an etching rate at each position on the top surface of the first substrate; calculating an inhibition condition for inhibiting etching by the etching solution by the inhibition portion based on the calculation result of the etching rate; a substrate processing apparatus that, when the etching liquid is being ejected from the first nozzle onto an upper surface of a second substrate different from the first substrate, controls the inhibition unit so as to inhibit the etching under the inhibition condition at a position on the upper surface of the second substrate where a rate of change of the etching rate is equal to or greater than zero toward the outer side in the radial direction.

17. the inhibition unit has a second nozzle that supplies a rinse liquid and a nozzle movement mechanism that can move the second nozzle in a horizontal direction above the substrate holding unit, 17. The substrate processing apparatus according to claim 16, wherein the inhibition of the etching by the inhibition section is performed by controlling a supply of a rinse liquid from the second nozzle to the second substrate and by controlling a position of the second nozzle relative to the second substrate by the control section.

18. The inhibition unit has a suction unit that sucks the etching solution discharged from the first nozzle, and a suction movement mechanism that moves the suction unit in a horizontal direction; 18. The substrate processing apparatus according to claim 16, wherein the inhibition of the etching by the inhibition unit is performed by the suction unit sucking the etching liquid on the second substrate and by the control unit controlling the position of the suction unit relative to the second substrate.

19. A substrate processing method for a substrate processing apparatus including a substrate holding unit that holds a substrate and rotates the substrate, a first nozzle that supplies an etching liquid to an upper surface of the substrate, and an inhibition unit that inhibits etching of the substrate by the etching liquid, Discharging the etching liquid from the first nozzle onto a first substrate; acquiring an etching rate at each position on the top surface of the first substrate; calculating an inhibiting condition that inhibits etching by the etching solution based on the obtained etching rate; a step of discharging the etching liquid from the first nozzle onto an upper surface of a second substrate different from the first substrate to process the second substrate; Equipped with a substrate processing method in which, in a step of processing the second substrate, when the etching solution is being discharged from the first nozzle onto the upper surface of the second substrate, the etching is inhibited under the inhibiting condition by the inhibiting portion at a position on the upper surface of the second substrate where a rate of change of the etching rate toward the outside in the radial direction is equal to or greater than zero.

20. the inhibition unit has a second nozzle that supplies a rinse liquid, 20. The substrate processing method according to claim 19, wherein the inhibition of the etching by the inhibition portion is performed by supplying a rinse liquid from the second nozzle to the upper surface of the second substrate at a predetermined position based on the inhibition condition.

21. 21. The substrate processing method according to claim 19, further comprising a step of measuring a thickness distribution in a radial direction of the first substrate before and after the etching liquid is discharged from the first nozzle onto the upper surface of the first substrate.

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