Substrate processing method and substrate processing device

Abstract

The substrate processing method includes the following steps: a step of holding a substrate having an amorphous silicon layer with a degenerate layer formed on the surface due to dry etching in a horizontal state (step S11); a step of modifying the degenerate layer by irradiating ultraviolet rays to the degenerate layer to generate a modified layer (step S12); and a step of supplying a chemical solution to the amorphous silicon layer having the modified layer on the surface to wet-etch the amorphous silicon layer (step S13). Thus, the wet etching of the amorphous silicon layer can be efficiently performed.

Description

Technical Field

[0001] The invention relates to a substrate processing method and a substrate processing device. Background Art

[0002] In recent years, as the pattern of a semiconductor substrate (hereinafter referred to as "substrate") has become finer, pattern formation based on multi-patterning has been performed. In multi-patterning, the upper surface and side surfaces of an intermediate pattern of amorphous silicon or the like formed on a substrate are covered with a coating film such as silicon oxide (SiOx), and the coating film on the upper surface of the intermediate pattern is removed by anisotropic etching based on plasma etching. In addition, the intermediate pattern is removed by dry etching, so that the coating film (so-called side wall) covering the side surface of the intermediate pattern remains as a pattern finer than the intermediate pattern. Thereafter, dry etching is performed using the side wall as a mask to form a fine pattern.

[0003] On the other hand, Japanese Patent Application Publication No. 2018-19089 (Document 1) discloses a technology for wet etching a polycrystalline silicon film on a substrate by supplying a chemical solution containing TMAH (tetramethylammonium hydroxide) to the polycrystalline silicon film.

[0004] However, in the above-mentioned multiple patterning, when the intermediate pattern is removed by dry etching, polymer residues may remain between the side walls, which may cause pattern formation defects in the subsequent film forming process and etching process. Therefore, a technology for supplying a chemical solution onto a substrate and removing the intermediate pattern of amorphous silicon by wet etching has been studied.

[0005] However, when removing the intermediate pattern of amorphous silicon by wet etching, it is known that the etching rate is much lower than the etching rate in the usual wet etching of amorphous silicon.

[0006] Therefore, after in-depth research, the inventors of the present application obtained the following discovery: during the plasma etching process, which is the pre-process of removing the intermediate pattern of amorphous silicon (i.e., the amorphous silicon layer), oxygen, carbon, etc. are incident on the upper surface of the intermediate pattern exposed from the coating film such as silicon oxide, and the above-mentioned etching rate decreases due to the deterioration of the upper surface caused by the incidence. Summary of the invention

[0007] Problems to be solved by the invention

[0008] The present invention relates to a substrate processing method, and aims to efficiently perform wet etching of an amorphous silicon layer.

[0009] A substrate processing method according to a preferred embodiment of the present invention includes the following steps: a) holding a substrate having an amorphous silicon layer with a degenerate layer formed on the surface due to dry etching in a horizontal state; b) modifying the degenerate layer by irradiating ultraviolet light to the degenerate layer to generate a modified layer; and c) supplying a chemical solution to the amorphous silicon layer having the modified layer on the surface to wet-etch the amorphous silicon layer. Thus, the wet etching of the amorphous silicon layer can be efficiently performed.

[0010] Preferably, in the dry etching, the coating film formed on the surface of the amorphous silicon layer is etched using plasma generated using a fluorocarbon-based gas and an oxygen gas.

[0011] The amorphous silicon layer is preferably an intermediate pattern formed in the middle of multiple patterning of the substrate. In the dry etching, the coating film covering the upper surface and side surfaces of the intermediate pattern is anisotropically etched, so that the upper surface of the intermediate pattern is exposed from the coating film, and the side walls of the coating film covering the side surfaces of the intermediate pattern are formed. In the wet etching, the intermediate pattern is removed and the side walls remain.

[0012] The wavelength of the ultraviolet rays is preferably 250 nm or less.

[0013] Preferably, the cumulative irradiation amount of the ultraviolet rays in the step b) is 1000 mJ / cm 2 above.

[0014] The ultraviolet irradiation in the step b) is preferably performed in a low-oxygen atmosphere.

[0015] Preferably, in the step b), the ultraviolet irradiation area on the substrate is scanned, and the cumulative irradiation amount of the ultraviolet ray to the thick region of the altered layer in the amorphous silicon layer is greater than the cumulative irradiation amount of the ultraviolet ray to the thin region of the altered layer.

[0016] Preferably, in the step c), the discharge position of the chemical solution on the substrate is scanned. The discharge time of the chemical solution for the thick modified layer region of the amorphous silicon layer is longer than the discharge time of the chemical solution for the thin modified layer region.

[0017] Preferably, the substrate processing method further comprises a step of supplying another chemical solution to the amorphous silicon layer between the step b) and the step c) to remove a natural oxide film on the surface of the amorphous silicon layer.

[0018] The present invention also relates to a substrate processing device. A substrate processing device of a preferred embodiment of the present invention comprises: a substrate holding unit that holds a substrate having an amorphous silicon layer with a degenerate layer formed on the surface due to dry etching in a horizontal state; an ultraviolet irradiation unit that modifies the degenerate layer by irradiating ultraviolet rays to the degenerate layer to generate a modified layer; and a chemical liquid supply unit that supplies a chemical liquid to the amorphous silicon layer having the modified layer on the surface to wet-etch the amorphous silicon layer. Thus, wet etching of the amorphous silicon layer can be efficiently performed.

[0019] Preferably, in the dry etching, the coating film formed on the surface of the amorphous silicon layer is etched with plasma generated using a fluorocarbon-based gas and an oxygen gas.

[0020] The amorphous silicon layer is preferably an intermediate pattern formed in the middle of multiple patterning of the substrate. In the dry etching, the coating film covering the upper surface and side surfaces of the intermediate pattern is anisotropically etched, so that the upper surface of the intermediate pattern is exposed from the coating film, and the side walls of the coating film covering the side surfaces of the intermediate pattern are formed. In the wet etching, the intermediate pattern is removed and the side walls remain.

[0021] The wavelength of the ultraviolet rays is preferably 250 nm or less.

[0022] Preferably, the cumulative irradiation amount of the ultraviolet rays to the amorphous silicon layer is 1000 mJ / cm 2 above.

[0023] It is preferable that the irradiation of the amorphous silicon layer with ultraviolet rays is performed in a low-oxygen atmosphere.

[0024] Preferably, the substrate processing apparatus further comprises an irradiation control unit for controlling the ultraviolet irradiation unit. The ultraviolet irradiation unit comprises: an ultraviolet lamp for irradiating the ultraviolet rays to the substrate; and an irradiation area scanning mechanism for scanning the irradiation area of ​​the ultraviolet rays on the substrate. By controlling at least one of the ultraviolet lamp and the irradiation area scanning mechanism by the irradiation control unit, the cumulative irradiation amount of the ultraviolet rays for the thick region of the metamorphic layer in the amorphous silicon layer is greater than the cumulative irradiation amount of the ultraviolet rays for the thin region of the metamorphic layer.

[0025] Preferably, the substrate processing apparatus further comprises a supply control unit for controlling the chemical solution supply unit. The chemical solution supply unit comprises: a chemical solution discharge unit for discharging the chemical solution toward the substrate; and a discharge position scanning mechanism for scanning a discharge position of the chemical solution on the substrate. The supply control unit controls the discharge position scanning mechanism so that the discharge time of the chemical solution for the region where the modified layer is thick in the amorphous silicon layer is longer than the discharge time of the chemical solution for the region where the modified layer is thin.

[0026] Preferably, the substrate processing apparatus further includes another chemical solution supplying unit for supplying another chemical solution to the amorphous silicon layer between the irradiation of the ultraviolet rays to the amorphous silicon layer and the supply of the chemical solution to remove a natural oxide film on the surface of the amorphous silicon layer.

[0027] The above-mentioned object and other objects, features, aspects and advantages will become more apparent from the following detailed description of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a side view of the substrate processing apparatus according to the first embodiment.

[0029] Figure 2 : is a block diagram showing a processing liquid supply unit.

[0030] Figure 3 is a cross-sectional view showing a portion near the upper surface of the substrate.

[0031] Figure 4 is a cross-sectional view showing a portion near the upper surface of the substrate.

[0032] Figure 5 is a cross-sectional view showing a portion near the upper surface of the substrate.

[0033] Figure 6 It is a diagram showing an example of a processing flow of a substrate.

[0034] Figure 7 is a graph showing the etching rate of an amorphous silicon layer.

[0035] Figure 8 A diagram showing a portion of a processing flow of a substrate.

[0036] Fig. 9 : is a block diagram showing a processing liquid supply unit.

[0037] Fig.10 It is a side view of the substrate processing apparatus according to the second embodiment. DETAILED DESCRIPTION

[0038] Figure 11 is a side view showing the structure of a substrate processing apparatus 1 according to the first embodiment of the present invention. The substrate processing apparatus 1 is a single-sheet type apparatus that processes semiconductor substrates 9 (hereinafter referred to as "substrates 9") one by one. The substrate processing apparatus 1 supplies a processing liquid to the substrate 9 to process it. Figure 1 , a part of the structure of the substrate processing apparatus 1 is shown in cross section.

[0039] The substrate processing device 1 includes a substrate holding portion 31, a substrate rotating mechanism 33, a cup portion 4, a processing liquid supply portion 5, a control portion 6, an ultraviolet irradiation portion 7, and a housing 11. The substrate holding portion 31, the substrate rotating mechanism 33, the cup portion 4, the ultraviolet irradiation portion 7, etc. are accommodated in the internal space of the housing 11. Figure 1 In the figure, the housing 11 is shown in cross section (in Fig.10 The same also applies to the case 11. An airflow forming section 12 is provided at the top cover of the housing 11. The airflow forming section 12 supplies gas to the internal space and forms an airflow flowing downward (so-called downflow). As the airflow forming section 12, for example, a FFU (fan filter unit) is used.

[0040] The control unit 6 is arranged outside the housing 11, and controls the substrate holding unit 31, the substrate rotating mechanism 33, the processing liquid supply unit 5, the ultraviolet irradiation unit 7, etc. The control unit 6 includes, for example, a common computer having a processor, a memory, an input / output unit, and a bus. The bus is a signal circuit that connects the processor, the memory, and the input / output unit. The memory stores programs and various information. The processor uses the memory, etc. to perform various processes (for example, numerical calculations) according to the programs stored in the memory. The input / output unit includes a keyboard and a mouse that receive input from the operator, a display that displays output from the processor, etc., and a sending unit that sends output from the processor, etc.

[0041] The control unit 6 includes a storage unit 61, an irradiation control unit 62, and a supply control unit 63. The storage unit 61 is mainly implemented by a memory, and stores various information such as the processing process of the substrate 9. The irradiation control unit 62 is mainly implemented by a processor, and controls the ultraviolet irradiation unit 7 and the like according to the processing process and the like stored in the storage unit 61. The supply control unit 63 is mainly implemented by a processor, and controls the processing liquid supply unit 5 and the like according to the processing process and the like stored in the storage unit 61.

[0042] The substrate holding part 31 faces the lower main surface (i.e., the lower surface) of the horizontal substrate 9 and holds the substrate 9 from the lower side. The substrate holding part 31 is, for example, a mechanical chuck that mechanically supports the substrate 9. The substrate holding part 31 is provided to be rotatable around a central axis J1 extending in the vertical direction.

[0043] The substrate holding portion 31 includes a holding portion body and a plurality of chuck pins. The holding portion body is a roughly disk-shaped component opposite to the lower surface of the substrate 9. A plurality of chuck pins are arranged at roughly equal angles along the circumferential direction (hereinafter, also referred to as "circumferential direction") centered on the central axis J1 at the peripheral portion of the holding portion body. Each chuck pin protrudes upward from the upper surface of the holding portion body to support the substrate 9 in a manner that contacts the peripheral area and side surface of the lower surface of the substrate 9. It should be noted that the substrate holding portion 31 can also be a vacuum suction cup that adsorbs the central portion of the lower surface of the substrate 9 and holds it.

[0044] The substrate rotating mechanism 33 is arranged below the substrate holding part 31. The substrate rotating mechanism 33 rotates the substrate 9 together with the substrate holding part 31 about the central axis J1. The substrate rotating mechanism 33 includes, for example, an electric rotary motor whose rotating shaft is connected to the holding part body of the substrate holding part 31. The substrate rotating mechanism 33 may also have other structures such as a hollow motor.

[0045] The processing liquid supply unit 5 supplies a plurality of processing liquids to the substrate 9 separately. The plurality of processing liquids include, for example, a chemical solution and a rinse solution described later. The processing liquid supply unit 5 includes a nozzle 51, an arm 511, and a nozzle rotating mechanism 512. The nozzle 51 supplies the processing liquid from the upper side of the substrate 9 to the upper main surface of the substrate 9 (hereinafter referred to as "upper surface 91"). The nozzle 51 is formed of a resin having high chemical resistance, such as Teflon (registered trademark).

[0046] The arm 511 is a rod-shaped member extending in a substantially horizontal direction, and supports the nozzle 51. The nozzle rotating mechanism 512 is arranged outside the cup-shaped portion 4 in a radial direction (hereinafter, also referred to as "radial direction") centered on the central axis J1. The nozzle rotating mechanism 512 includes, for example, an electric rotary motor having a rotation axis extending in the vertical direction. The rotation axis is connected to one end of the arm 511. The nozzle rotating mechanism 512 moves the nozzle 51 in a horizontal direction by rotating the arm 511 around the rotation axis in the vertical direction, and retreats from a retreat position radially outward of the cup-shaped portion 4 above the substrate 9.

[0047] The cup-shaped portion 4 is an annular component centered on the central axis J1. The cup-shaped portion 4 is arranged around the substrate 9 and the substrate holding portion 31 in the entire circumference, covering the sides and bottom of the substrate 9 and the substrate holding portion 31. The cup-shaped portion 4 is a liquid receiving container that receives liquids such as processing liquids that fly toward the surroundings from the rotating substrate 9. The inner surface of the cup-shaped portion 4 is formed of, for example, a waterproof material. Regardless of whether the substrate 9 is rotating or stationary, the cup-shaped portion 4 is stationary in the circumferential direction. A discharge port (omitted in the figure) is provided at the bottom of the cup-shaped portion 4 for discharging the processing liquid received by the cup-shaped portion 4 to the outside of the housing 11. The cup-shaped portion 4 can be moved in the up and down directions by a lifting mechanism (omitted in the figure). Figure 1The position around the substrate 9 shown is moved between a processing position and a retreat position located below the processing position.

[0048] The cup 4 can also be Figure 1 When the cup-shaped portion 4 has a stacked structure, the cups can independently move in the vertical direction and are switched according to the type of processing liquid scattered from the substrate 9 to receive the processing liquid.

[0049] Figure 2 1 is a block diagram showing the processing liquid supply unit 5 of the substrate processing apparatus 1. Figure 2 , the components other than the treatment liquid supply unit 5 are also shown. The treatment liquid supply unit 5 includes a liquid supply unit 52 and a rinse liquid supply unit 53. The liquid supply unit 52 includes a nozzle 51, an arm 511 (see Figure 1 ), nozzle rotating mechanism 512 (see Figure 1 ), a chemical liquid supply source 521 and a chemical liquid pipe 522. The nozzle 51 is connected to the chemical liquid supply source 521 via the chemical liquid pipe 522. The nozzle 51 is a chemical liquid discharge part that discharges the chemical liquid sent from the chemical liquid supply source 521 to the upper surface 91 of the substrate 9. The chemical liquid is an etching liquid used for wet etching of the substrate 9. The etching liquid is, for example, ammonium hydroxide (NH 4 OH) aqueous solution or other alkaline etching solution.

[0050] The rinsing liquid supply unit 53 includes the above-mentioned nozzle 51, the arm 511, the nozzle rotating mechanism 512, the rinsing liquid supply source 531, and the rinsing liquid pipe 532. The nozzle 51 is connected to the rinsing liquid supply source 531 via the rinsing liquid pipe 532. The nozzle 51 is a rinsing liquid discharge unit that discharges the rinsing liquid sent from the rinsing liquid supply source 531 toward the upper surface 91 of the substrate 9. As the rinsing liquid, for example, an aqueous treatment liquid such as DIW (De-ionized Water), carbonated water, ozone water, or hydrogen water is used.

[0051] As described above, the nozzle 51, the arm 511, and the nozzle rotating mechanism 512 are shared by the chemical liquid supply unit 52 and the rinse liquid supply unit 53. For example, a discharge port for the chemical liquid and a discharge port for the rinse liquid are independently provided at the lower end of the nozzle 51, and different types of processing liquids are supplied to the upper surface 91 of the substrate 9 through different pipes and discharge ports. In addition, the nozzle for discharging the chemical liquid and the nozzle for discharging the rinse liquid may be provided separately and independently of each other.

[0052] The ultraviolet irradiation unit 7 includes an ultraviolet lamp 71 and a lamp lifting mechanism 72. The ultraviolet lamp 71 is a substantially disk-shaped lamp disposed above the substrate 9. The lamp lifting mechanism 72 is disposed radially outside the cup-shaped portion 4. The lamp lifting mechanism 72 includes, for example, an electric linear motor or a ball screw and an electric rotary motor. The lamp lifting mechanism 72 is connected to the ultraviolet lamp 71 to move the ultraviolet lamp 71 in the vertical direction. The ultraviolet lamp 71 can be moved in the vertical direction. Figure 1 The nozzle 51 moves between a retreat position indicated by a solid line in FIG. 1 and an irradiation position (indicated by a two-dot chain line) located below the retreat position. When the ultraviolet lamp 71 moves from the retreat position to the irradiation position, the nozzle 51 retreats from above the substrate 9 to the retreat position under the action of the nozzle rotating mechanism 512. The ultraviolet lamp 71 irradiates ultraviolet rays toward the entire upper surface 91 of the substrate 9 from the irradiation position.

[0053] As the ultraviolet lamp 71, an excimer lamp or a low-pressure mercury lamp can be used. The wavelength of ultraviolet rays emitted from the ultraviolet lamp 71 is preferably 250 nm or less, more preferably 172 nm or less. The lower limit of the wavelength of the ultraviolet rays is not particularly limited, and is, for example, 120 nm or more.

[0054] Figure 3 This is a cross-sectional view showing an enlarged portion of the upper surface 91 of the substrate 9. Figure 3 In the illustrated substrate 9, an insulating film 94 is formed on the upper surface of a silicon substrate main body 93, a titanium nitride (TiN) film 95 is formed on the upper surface of the insulating film 94, and a silicon nitride film 96 is formed on the upper surface of the titanium nitride film 95. The insulating film 94, the titanium nitride film 95, and the silicon nitride film 96 are respectively provided on the upper surface of the silicon substrate main body 93 with substantially uniform thickness. Figure 3 On the entire upper surface of the silicon substrate main body 93.

[0055] An amorphous silicon layer 97 is formed on the upper surface of the silicon nitride film 96. The amorphous silicon layer 97 is a fine pattern that is a collection of a plurality of pattern elements 971. The amorphous silicon layer 97 is an intermediate pattern formed in the middle of the multi-patterning of the substrate 9. Figure 3 Four pattern elements 971 are shown. Figure 3 The width of the pattern element 971 in the horizontal direction is, for example, 30 nm to 100 nm. The height of the pattern element 971 in the vertical direction is, for example, 20 nm to 100 nm. The upper surface of the silicon nitride film 96 is exposed between adjacent pattern elements 971 .

[0056] The side surfaces of each pattern element 971 of the amorphous silicon layer 97 are covered by a side wall 981. The side wall 981 is a thin film formed of silicon oxide, silicon nitride, silicon oxynitride, or the like. Figure 3The width of the sidewall 981 in the left-right direction is smaller than the width of the pattern element 971, and is, for example, 10 nm to 20 nm. The height of the sidewall 981 in the vertical direction is substantially the same as the height of the pattern element 971, and the upper and lower ends of the sidewall 981 are located at substantially the same positions in the vertical direction as the upper and lower ends of the pattern element 971. The upper surface of the pattern element 971 is not covered by the thin film formed of the above-mentioned silicon oxide, silicon nitride or silicon oxynitride, and is exposed from the two sidewalls 981 covering the two side surfaces of the pattern element 971.

[0057] Figure 3 The substrate 9 shown in FIG. 1 is formed in another device different from the substrate processing device 1. Specifically, first, in a state where an insulating film 94, a titanium nitride film 95, a silicon nitride film 96 and an amorphous silicon layer 97 (i.e., an intermediate pattern) are sequentially formed on a silicon substrate main body 93, as shown in FIG. Figure 4 As shown, a coating film 98 is formed to cover the uppermost amorphous silicon layer 97. The coating film 98 is, for example, a silicon oxide film, a silicon nitride film, or a silicon oxynitride film. The coating film 98 covers the upper surface and side surfaces of each pattern element 971 of the amorphous silicon layer 97 in the entire surface, and the upper surface of the silicon nitride film 96 exposed between each pattern element 971. The formation of the coating film 98 is performed, for example, by CVD (Chemical Vapor Deposition: chemical vapor growth), PVD (Physical Vapor Deposition: physical vapor growth) or ALD (Atomic Layer Deposition: Atomic Layer Deposition).

[0058] Next, for Figure 4 The coating film 98 shown is dry-etched. The dry etching is, for example, plasma etching performed by using a fluorocarbon gas (CxFy) and an oxygen gas to generate a plasma. The dry etching is essentially anisotropic etching that etches only in the up and down directions. By performing the anisotropic etching on the coating film 98, the upper surface of each pattern element 971 of the amorphous silicon layer 97 is exposed from the coating film 98, and the upper surface of the silicon nitride film 96 between the adjacent pattern elements 971 is also exposed from the coating film 98. In addition, the side surfaces of each pattern element 971 of the amorphous silicon layer 97 are maintained in a state of being covered by the coating film 98. Thus, a Figure 3 The side wall 981 covering the side of each pattern element 971 is formed on the above-mentioned coating film 98 (see Figure 4 ) is the area remaining after dry etching.

[0059] In the substrate 9, during the dry etching, oxygen (O), carbon (C), fluorine (F), etc. are incident on the upper surface of each pattern element 971 exposed from the coating film 98 (that is, the surface of the amorphous silicon layer 97 on the opposite side to the silicon substrate main body 93), and as shown in FIG. Figure 5 As shown in FIG. 1 , a modified layer 972 is formed on the upper surface of each pattern element 971. Figure 5 In the figure, the altered layer 972 is marked with parallel oblique lines that are different from those in the pattern element 971 other than the altered layer 972. It is believed that in the altered layer 972 originating from the dry etching in the previous process, oxygen and carbon incident on the amorphous silicon layer 97 are bonded with silicon of the amorphous silicon layer 97 to form "Si-O bonds" and "Si-C bonds". And, it is believed that these Si-O bonds and Si-C bonds are the factors that hinder the wet etching of the amorphous silicon layer 97 in the substrate processing device 1 (described later). It should be noted that there is also the possibility that only one of the Si-O bonds and the Si-C bonds is formed in the altered layer 972.

[0060] Next, refer to Figure 6 The processing of the substrate 9 in the substrate processing apparatus 1 is described. In the substrate processing apparatus 1, first, Figure 3 The substrate 9 having the amorphous silicon layer 97 and the sidewall 981 is moved into Figure 1 The substrate processing apparatus 1 shown in FIG. 1 is held in a horizontal state by the substrate holding portion 31 (step S11). Figure 5 As shown, a degenerated layer 972 resulting from dry etching is formed on the surface of the amorphous silicon layer 97 .

[0061] Next, the ultraviolet irradiation unit 7 is controlled by the irradiation control unit 62 so that the ultraviolet lamp 71 is arranged at Figure 1 The ultraviolet light is emitted from the ultraviolet lamp 71 toward the entire upper surface 91 of the substrate 9 at the irradiation position indicated by the double-dashed line in FIG. 1 . Thus, the ultraviolet light is irradiated to the metamorphic layer 972 of the amorphous silicon layer 97. The ultraviolet light irradiation from the ultraviolet lamp 71 to the metamorphic layer 972 is performed for a predetermined time. Thus, the Si-O bond and the Si-C bond in the metamorphic layer 972 are cut. As a result, the metamorphic layer 972 is modified to generate a modified layer (step S12).

[0062] In step S12, as described above, it is preferred that the wavelength of the ultraviolet rays irradiated to the amorphous silicon layer 97 is 250 nm or less. The energy of ultraviolet rays with a wavelength of 250 nm or less is 478 kJ / mol or more, which is greater than the bond energy of Si-O bond 443 kJ / mol and the bond energy of Si-C bond 337 kJ / mol. Therefore, by irradiating the modified layer 972 with ultraviolet rays with a wavelength of 250 nm or less, the Si-O bond and the Si-C bond of the modified layer 972 can be properly cut.

[0063] In step S12, the accumulated irradiation amount of ultraviolet rays irradiated from the ultraviolet lamp 71 to the altered layer 972 of the amorphous silicon layer 97 is preferably 1000 mJ / cm 2 The upper limit of the cumulative irradiation dose is not particularly limited, but is, for example, 3000 mJ / cm 2 The cumulative irradiation amount is calculated by dividing the illuminance (mW / cm 2 ) is calculated by multiplying the ultraviolet irradiation time (sec (seconds)).

[0064] Preferably, the ultraviolet irradiation to the amorphous silicon layer 97 in step S12 is performed in a low oxygen atmosphere. More preferably, the ultraviolet irradiation is performed in an atmosphere with an oxygen concentration of 1 volume % or less. The low oxygen atmosphere can be achieved by various methods. For example, nitrogen (N) can be supplied from the air flow forming section 12 to the internal space of the housing 11. 2 The above-mentioned low oxygen atmosphere can be achieved by filling the inner space of the housing 11 with an inert gas such as a ) gas and making the inner space of the housing 11 an inert gas atmosphere. The supply of the inert gas to the housing 11 can also be performed using a gas supply mechanism other than the gas flow forming unit 12. In addition, the above-mentioned ultraviolet irradiation can also be performed in a low oxygen atmosphere by supplying an inert gas only to the space between the ultraviolet lamp 71 and the substrate 9 from the side thereof.

[0065] When the ultraviolet irradiation to the amorphous silicon layer 97 is completed, the ultraviolet lamp 71 is moved from the above-mentioned irradiation position to the retreat position by the lamp lifting mechanism 72. In addition, the nozzle 51 is moved from the retreat position to the top of the substrate 9 by the nozzle rotating mechanism 512. Then, the substrate 9 starts to rotate by the substrate rotating mechanism 33, and the supply control unit 63 controls the chemical supply unit 52, so that the chemical is supplied from the nozzle 51 to the rotating substrate 9. Specifically, the chemical is discharged from the nozzle 51 toward the center of the upper surface 91 of the substrate 9 in the form of a liquid column. The chemical supplied to the substrate 9 spreads radially outward from the center of the substrate 9 under the action of centrifugal force and is applied to the entire upper surface 91 of the substrate 9.

[0066] The chemical solution is an etching solution such as an aqueous ammonium hydroxide solution, and the chemical solution is supplied to the amorphous silicon layer 97 having the modified layer on the surface, thereby wet etching the amorphous silicon layer 97 (step S13). On the substrate 9, each pattern element 971 of the amorphous silicon layer 97 is selectively etched away, and the sidewall 981 covering the side of the pattern element 971 is not etched and remains on the silicon nitride film 96.

[0067] In the substrate processing apparatus 1, during the wet etching of the amorphous silicon layer 97, the nozzle rotating mechanism 512 may be driven by the supply control unit 63 so that the nozzle 51 reciprocates substantially in the radial direction above the substrate 9. This can improve the uniformity of applying the etching liquid to the entire surface of the substrate 9.

[0068] Figure 7 1 is a graph showing the etching rate of the amorphous silicon layer 97 in the wet etching. The etching rate is a case where a 65°C ammonium hydroxide aqueous solution prepared by mixing ammonium hydroxide and DIW at a ratio of 1:15 is used as an etching solution. Example 1 in the figure shows the etching rate of the amorphous silicon layer 97 having the modified layer formed on the surface. In Example 1, the cumulative irradiation amount of ultraviolet rays to the modified layer 972 in the step S12 is 1000 mJ / cm 2 In addition, Comparative Example 1 shows the etching rate of the amorphous silicon layer 97 having the metamorphic layer 972 formed on the surface (i.e., the amorphous silicon layer before ultraviolet irradiation). Comparative Example 2 shows the etching rate of the amorphous silicon layer 97 having no metamorphic layer 972 and no modified layer formed on the surface (i.e., the amorphous silicon layer not subjected to plasma etching).

[0069] like Figure 7 As shown, the etching rate of Comparative Example 1 is very low because the wet etching is hindered by the degenerate layer 972, and is about 3% of the etching rate of Comparative Example 2. Therefore, in the state of Comparative Example 1, the wet etching of the amorphous silicon layer 97 is not substantially performed. On the other hand, the etching rate of Example 1 is restored to about 43% of the etching rate of Comparative Example 2 because the degenerate layer 972 is modified by ultraviolet irradiation. Therefore, the wet etching of the amorphous silicon layer 97 can be properly performed. It should be noted that the etching rate of Example 1 is more than 10 times the etching rate of Comparative Example 1.

[0070] In the substrate processing apparatus 1 , the supply of the chemical solution (ie, etching solution) from the nozzle 51 is continued for a predetermined time, so that all the pattern elements 971 of the amorphous silicon layer 97 are removed from between the side walls 981 , and wet etching of the substrate 9 is completed.

[0071] When the wet etching is finished, the rinsing liquid supply unit 53 is controlled by the supply control unit 63, so that the rinsing liquid is supplied from the nozzle 51 to the upper surface 91 of the rotating substrate 9, and the substrate 9 is rinsed (step S14). Thereafter, the supply of the rinsing liquid is stopped, and the substrate 9 is dried (step S15). During the drying process, the rotation speed of the substrate 9 increases, and the residual processing liquid on the substrate 9 is scattered radially outward from the edge of the substrate 9 under the action of centrifugal force and removed from the substrate 9. In the above steps S13 to S15, the processing liquids such as the chemical solution and the rinsing liquid scattered radially outward from the substrate 9 are received by the cup-shaped portion 4 and discharged to the outside of the housing 11. The substrate 9 after the drying process is carried out of the substrate processing device 1 and carried into another device for performing a post-process. In the other device, for example, the silicon nitride film 96 is dry-etched using the side wall 981 as a mask. In the substrate processing device 1, the above steps S11 to S15 are sequentially performed on a plurality of substrates 9.

[0072] As described above, the above-mentioned substrate processing method includes the following steps: a step of maintaining a substrate 9 having an amorphous silicon layer 97 having a metamorphic layer 972 formed on the surface thereof due to dry etching in a horizontal state (step S11); a step of modifying the metamorphic layer 972 to generate a modified layer by irradiating the metamorphic layer 972 with ultraviolet rays (step S12); and a step of supplying a chemical solution to the amorphous silicon layer 97 having the modified layer on the surface thereof and wet etching the amorphous silicon layer 97 (step S13).

[0073] This can increase the etching rate of the amorphous silicon layer 97 that has been reduced by the altered layer 972. As a result, the amorphous silicon layer 97 can be wet-etched efficiently.

[0074] In the dry etching, it is preferred to etch the coating film 98 formed on the surface of the amorphous silicon layer 97 with plasma generated by using a fluorocarbon gas and an oxygen gas. In the substrate processing method, the Si-O bonds and Si-C bonds in the modified layer 972 can be cut by irradiating the amorphous silicon layer 97 with ultraviolet rays, thereby increasing the etching rate of the amorphous silicon layer 97 which has been reduced due to the Si-O bonds and the Si-C bonds.

[0075] As described above, the amorphous silicon layer 97 is preferably an intermediate pattern formed in the middle of the multiple patterning of the substrate 9. In addition, in the above-mentioned dry etching, by anisotropically etching the coating film 98 covering the upper surface and the side surface of the intermediate pattern, the upper surface of the intermediate pattern is exposed from the coating film 98, and the side wall 981 of the coating film 98 covering the side surface of the intermediate pattern is formed. And, in the above-mentioned wet etching, the intermediate pattern is removed and the side wall 981 remains. In the above-mentioned substrate processing method, the etching rate of the amorphous silicon layer 97 can be increased by irradiating the altered layer 972 with ultraviolet rays, so that the above-mentioned multiple patterning of the substrate 9 can be efficiently performed.

[0076] As described above, it is preferred that the wavelength of the ultraviolet rays irradiated to the modified layer 972 in step S12 is 250 nm or less. The energy of ultraviolet rays having a wavelength of 250 nm or less is greater than the bond energy of the Si-O bond and the bond energy of the Si-C bond, so that the modified layer 972 can be modified appropriately by ultraviolet irradiation (i.e., the Si-O bond and the Si-C bond in the modified layer 972 are cut).

[0077] As described above, the cumulative irradiation amount of ultraviolet rays in step S12 is preferably 1000 mJ / cm 2 As described above, the altered layer 972 can be appropriately modified by ultraviolet irradiation.

[0078] As described above, the ultraviolet irradiation in step S12 is preferably performed in a low-oxygen atmosphere. This can prevent or suppress the ultraviolet rays from being absorbed by oxygen during irradiation of the amorphous silicon layer 97. As a result, the altered layer 972 can be efficiently modified by ultraviolet irradiation.

[0079] The substrate processing apparatus 1 includes a substrate holding portion 31, an ultraviolet irradiation portion 7, and a chemical solution supply portion 52. The substrate holding portion 31 holds the substrate 9 having an amorphous silicon layer 97 having a degenerate layer 972 formed on the surface due to dry etching in a horizontal state. The ultraviolet irradiation portion 7 modifies the degenerate layer 972 by irradiating ultraviolet rays to the degenerate layer 972 to generate a modified layer. The chemical solution supply portion 52 supplies a chemical solution to the amorphous silicon layer 97 having the modified layer on the surface to perform wet etching on the amorphous silicon layer 97. Thus, as described above, the etching rate of the amorphous silicon layer 97 that has been reduced due to the degenerate layer 972 can be increased. As a result, the wet etching of the amorphous silicon layer 97 can be efficiently performed.

[0080] In the processing of the substrate 9 by the substrate processing apparatus 1, as Figure 8As shown, pretreatment (step S121) may be performed on the amorphous silicon layer 97 between the irradiation of the amorphous silicon layer 97 with ultraviolet rays in step S12 and the supply of a chemical solution (i.e., etching solution) to the amorphous silicon layer 97 in step S13. In step S121, a chemical solution (e.g., hydrofluoric acid (HF)) different from the chemical solution in step S13 is supplied to the amorphous silicon layer 97, thereby removing the surface natural oxide film of the surface of the amorphous silicon layer 97 (i.e., the upper surface of the metamorphic layer 972).

[0081] In this case, if Fig. 9 As shown, the processing liquid supply unit 5 of the substrate processing apparatus 1 is provided with an other liquid supply unit 54 for supplying the other liquid to the substrate 9 in addition to the liquid supply unit 52 and the rinse liquid supply unit 53. The other liquid supply unit 54 includes a nozzle 51, an arm 511 (see Figure 1 ), nozzle rotating mechanism 512 (see Figure 1 ), other chemical liquid supply source 541 and other chemical liquid piping 542. The nozzle 51 is connected to the other chemical liquid supply source 541 via the other chemical liquid piping 542. The nozzle 51 is also an other chemical liquid discharge unit that discharges the other chemical liquid (for example, dilute hydrofluoric acid at room temperature with a concentration of 0.3%) sent from the other chemical liquid supply source 541 to the upper surface 91 of the substrate 9. It should be noted that the nozzle for discharging the other chemical liquid can also be provided independently of the nozzle for discharging the etching liquid.

[0082] As described above, the substrate processing method preferably further includes a step (step S121) of supplying another chemical solution to the amorphous silicon layer 97 between step S12 and step S13 to remove the surface natural oxide film of the amorphous silicon layer 97. In this way, by removing the surface natural oxide film before wet etching of the amorphous silicon layer 97, the etching rate reduction caused by the surface natural oxide film can be prevented or suppressed. As a result, the wet etching of the amorphous silicon layer 97 can be further efficiently performed.

[0083] Next, a substrate processing apparatus 1 a according to a second embodiment of the present invention will be described. Fig.10 1 is a side view showing the structure of the substrate processing apparatus 1a. Figure 3 The substrate 9 shown is subjected to Figure 1 The substrate processing apparatus 1 shown in the figure performs substantially the same processing as that shown in the figure, and wet-etches the amorphous silicon layer 97 .

[0084] The substrate processing apparatus 1a includes an irradiation unit 14, a liquid processing unit 15, a control unit 6, and a housing 11. The irradiation unit 14 and the liquid processing unit 15 are arranged inside one housing 11. The control unit 6 has Figure 1 The control unit 6 shown in FIG. 6 has the same structure as that of the control unit 6. The control unit 6 includes the storage unit 61, the irradiation control unit 62, and the supply control unit 63 as described above.

[0085] The irradiation unit 14 includes a first substrate holding portion 31a and an ultraviolet irradiation portion 7a. Figure 1 The substrate holding portion 31 shown in the figure has a substantially similar structure and holds the substrate 9 in a horizontal state from the bottom. Fig.10 In the illustrated example, the substrate rotating mechanism 33 is not provided in the irradiation unit 14, and the first substrate holding portion 31a does not rotate.

[0086] The ultraviolet irradiation section 7a includes an ultraviolet lamp 71a and an irradiation area scanning mechanism 73. The ultraviolet lamp 71a is a roughly rod-shaped lamp extending in a roughly straight line in a direction perpendicular to the paper surface in the figure. The ultraviolet rays emitted from the ultraviolet lamp 71a are irradiated to a strip-shaped or linear irradiation area extending in a roughly straight line in a direction perpendicular to the paper surface on the substrate 9. The irradiation area is a part of the upper surface 91 of the substrate 9, and crosses the upper surface 91 of the substrate 9 in a direction perpendicular to the paper surface. The ultraviolet lamp 71a uses an excimer lamp or a low-pressure mercury lamp, etc., similarly to the ultraviolet lamp 71 described above. It is preferred that the wavelength of the ultraviolet rays emitted from the ultraviolet lamp 71a is less than 250nm, and more preferably less than 172nm. The lower limit of the wavelength of the ultraviolet rays is not particularly limited, for example, it is more than 120nm.

[0087] The irradiation area scanning mechanism 73 moves the ultraviolet lamp 71a in the left-right direction in the figure above the substrate 9, thereby scanning the irradiation area on the substrate 9 in the left-right direction in the figure. The irradiation area scanning mechanism 73 includes, for example, an electric linear motor, a ball screw, and an electric rotary motor. In the substrate processing device 1a, the irradiation control unit 62 of the control unit 6 controls the irradiation area scanning mechanism 73, thereby controlling the moving speed of the ultraviolet lamp 71a and controlling the scanning speed of the ultraviolet irradiation area on the substrate 9. It should be noted that during the movement of the ultraviolet lamp 71a, the output from the ultraviolet lamp 71a is maintained substantially constant.

[0088] The liquid processing unit 15 has the same structure as the substrate holding unit 31 except that the ultraviolet irradiation unit 7 is omitted and a second substrate holding unit 31b is provided with the same structure as the substrate holding unit 31. Figure 1 In the following description, the same reference numerals are given to the components of the liquid processing unit 15 corresponding to the components of the substrate processing apparatus 1. In the substrate processing apparatus 1a, the substrate holding portion 31 for holding the substrate 9 in a horizontal state is constituted by the first substrate holding portion 31a and the second substrate holding portion 31b.

[0089] In the liquid processing unit 15, when the chemical liquid (i.e., etching liquid) is discharged from the nozzle 51 to the upper surface 91 of the substrate 9, the nozzle 51 is reciprocated in a substantially radial direction above the substrate 9 by the nozzle rotating mechanism 512. Thus, the discharge position of the chemical liquid on the upper surface 91 of the substrate 9 is scanned. In other words, the nozzle rotating mechanism 512 is a discharge position scanning mechanism that scans the discharge position of the chemical liquid on the upper surface 91 of the substrate 9. In the substrate processing device 1a, the nozzle rotating mechanism 512 is controlled by the supply control unit 63 of the control unit 6, so that the moving speed of the nozzle 51 is controlled, and the scanning speed of the discharge position of the chemical liquid on the substrate 9 is controlled.

[0090] The processing flow of the substrate 9 in the substrate processing device 1a is similar to Figure 6 In the processing of the substrate 9 in the substrate processing apparatus 1a, first, the substrate 9 having Figure 3 The substrate 9 having the amorphous silicon layer 97 and the sidewall 981 shown in FIG. 1 is carried into the substrate processing apparatus 1a and is held in a horizontal state by the first substrate holding portion 31a of the irradiation unit 14 (step S11). As described above, a degenerated layer 972 (see FIG. 1 ) caused by dry etching is formed on the surface of the amorphous silicon layer 97. Figure 5 ).

[0091] Next, the ultraviolet irradiation unit 7a of the irradiation unit 14 is controlled by the irradiation control unit 62, so that ultraviolet rays are irradiated to the modified layer 972 of the amorphous silicon layer 97. Specifically, ultraviolet rays are emitted from the ultraviolet lamp 71a and irradiated to the irradiation area extending in a substantially linear shape on the upper surface 91 of the substrate 9. In addition, the ultraviolet lamp 71a is scanned from the left side to the right side in the figure above the substrate 9 by using the irradiation area scanning mechanism 73, so that ultraviolet rays are irradiated to the entire upper surface 91 of the substrate 9. As a result, the Si-O bonds and Si-C bonds in the modified layer 972 are cut and the modified layer 972 is modified, thereby generating the above-mentioned modified layer (step S12).

[0092] In step S12, as described above, it is preferred that the wavelength of the ultraviolet rays irradiated to the amorphous silicon layer 97 is 250 nm or less. Thus, the modified layer 972 can be properly modified by ultraviolet irradiation (i.e., the Si-O bonds and Si-C bonds in the modified layer 972 are cut). In step S12, as described above, it is preferred that the cumulative irradiation amount of ultraviolet rays irradiated from the ultraviolet lamp 71a to the modified layer 972 of the amorphous silicon layer 97 is 1000 mJ / cm 2 As described above, the altered layer 972 can be appropriately modified by ultraviolet irradiation.

[0093] It is preferred that the ultraviolet irradiation to the amorphous silicon layer 97 in step S12 is performed in a low oxygen atmosphere. Thus, as described above, it is possible to prevent or suppress the ultraviolet rays from being absorbed by oxygen during the irradiation to the amorphous silicon layer 97. As a result, the modified layer 972 can be efficiently modified by ultraviolet irradiation. It should be noted that in step S12, the ultraviolet lamp 71a can be reciprocated in the left-right direction above the substrate 9, thereby performing multiple ultraviolet scans on the substrate 9.

[0094] After step S12 is completed, the substrate 9 is transported from the irradiation unit 14 to the liquid treatment unit 15 using a transport mechanism such as a robot (not shown), and is held in a horizontal state by the second substrate holding portion 31b of the liquid treatment unit 15. Next, the substrate 9 is rotated by the substrate rotating mechanism 33, and the supply control unit 63 controls the chemical solution supply unit 52 (see Figure 2 ) is controlled so that a chemical solution (i.e., etching solution) is supplied from the nozzle 51 to the rotating substrate 9. As described above, the nozzle 51 reciprocates in a substantially radial direction above the substrate 9 under the action of the nozzle rotating mechanism 512, and scans the discharge position of the chemical solution on the upper surface 91 of the substrate 9. In addition, by supplying the chemical solution to the amorphous silicon layer 97 having the modified layer on the surface, the amorphous silicon layer 97 is wet-etched (step S13).

[0095] After the wet etching is completed, a rinsing liquid is supplied from the nozzle 51 to the upper surface 91 of the rotating substrate 9 to perform a rinsing treatment on the substrate 9 (step S14). Thereafter, the supply of the rinsing liquid is stopped, and the substrate 9 is dried (step S15). In the substrate processing device 1a, the above-mentioned steps S11 to S15 are sequentially performed on a plurality of substrates 9. It should be noted that, in the substrate processing device 1a, the above-mentioned step S121 (see Figure 8 ).

[0096] In the substrate processing apparatus 1a, Figure 1 The substrate processing apparatus 1 shown in the figure can also increase the etching rate of the amorphous silicon layer 97 which has been reduced by the altered layer 972. Specifically, the etching rate of the amorphous silicon layer 97 can be increased by cutting the Si-O bonds and Si-C bonds in the altered layer 972. Thus, the amorphous silicon layer 97 can be wet-etched efficiently. As a result, the above-mentioned multiple patterning can be efficiently performed on the substrate 9.

[0097] As described above, in the substrate processing device 1a, the ultraviolet irradiation area on the substrate 9 is scanned in step S12. At this time, it is preferred that the irradiation area scanning mechanism 73 is controlled by the irradiation control unit 62 so that the scanning speed of the ultraviolet irradiation area for the thick region of the metamorphic layer 972 in the amorphous silicon layer 97 is lower than the scanning speed of the ultraviolet irradiation area for the thin region of the metamorphic layer 972. As a result, the cumulative irradiation amount of ultraviolet rays for the thick region of the metamorphic layer 972 in the amorphous silicon layer 97 is greater than the cumulative irradiation amount of ultraviolet rays for the thin region of the metamorphic layer 972. As a result, the modification uniformity of the metamorphic layer 972 of the amorphous silicon layer 97 as a whole can be improved. It should be noted that the improvement of the modification uniformity can be confirmed by the improvement of the uniformity of the etching rate of the amorphous silicon layer 97 as a whole.

[0098] In the substrate processing apparatus 1a, the output of the ultraviolet lamp 71a can be controlled by using the irradiation control unit 62 so that the irradiance of ultraviolet light for the thick region of the metamorphic layer 972 is greater than the irradiance of ultraviolet light for the thin region of the metamorphic layer 972. In this case, the scanning speed of the ultraviolet light irradiation region can be maintained unchanged, and the cumulative irradiation amount of ultraviolet light for the thick region of the metamorphic layer 972 in the amorphous silicon layer 97 is greater than the cumulative irradiation amount of ultraviolet light for the thin region of the metamorphic layer 972. As a result, the modification uniformity of the metamorphic layer 972 of the entire amorphous silicon layer 97 can be improved as described above.

[0099] As described above, in the substrate processing device 1a, the discharge position of the chemical solution on the substrate 9 is scanned in step S13. At this time, it is preferable that the nozzle rotating mechanism 512 (i.e., the discharge position scanning mechanism) is controlled by the supply control unit 63 so that the scanning speed of the discharge position of the chemical solution for the thick region of the metamorphic layer 972 in the amorphous silicon layer 97 is lower than the scanning speed of the discharge position of the chemical solution for the thin region of the metamorphic layer 972. As a result, the discharge time of the chemical solution for the thick region of the metamorphic layer 972 in the amorphous silicon layer 97 is longer than the discharge time of the chemical solution for the thin region of the metamorphic layer 972. As a result, the uniformity of wet etching of the entire amorphous silicon layer 97 (for example, the uniformity of the progress speed of wet etching) can be improved.

[0100] Various modifications can be made to the above-described substrate processing method and substrate processing apparatus 1 , 1 a .

[0101] For example, the ultraviolet irradiation onto the amorphous silicon layer 97 in step S12 does not necessarily have to be performed in a low-oxygen atmosphere, and may be performed in, for example, an air atmosphere.

[0102] In step S12, the cumulative amount of ultraviolet radiation applied to the amorphous silicon layer 97 may be appropriately changed according to the type and thickness of the altered layer 972. For example, the cumulative amount of ultraviolet radiation applied to the amorphous silicon layer 97 may be lower than 1000 mJ / cm 2 .

[0103] In step S12, the wavelength of ultraviolet rays irradiated to the amorphous silicon layer 97 may be appropriately changed according to the type and thickness of the altered layer 972. For example, the wavelength of ultraviolet rays irradiated to the amorphous silicon layer 97 may be longer than 250 nm.

[0104] The amorphous silicon layer 97 of the substrate 9 processed in the substrate processing apparatuses 1 and 1 a is not necessarily an intermediate pattern formed during the multi-patterning of the substrate 9 , but may be an amorphous silicon layer obtained by performing a process other than multi-patterning.

[0105] The altered layer 972 modified in the substrate processing apparatuses 1 and 1 a is not limited to a layer formed by plasma etching using plasma generated using a fluorocarbon gas and an oxygen gas, but may be a layer formed by altering the surface of the amorphous silicon layer 97 by other treatments.

[0106] In the substrate processing apparatus 1, the ultraviolet irradiation to the amorphous silicon layer 97 can also be performed by Fig.10 In the substrate processing apparatus 1a, ultraviolet irradiation for the amorphous silicon layer 97 may also be performed using the ultraviolet irradiation unit 7a shown in FIG. Figure 1 The ultraviolet irradiation unit 7 is shown. In the substrate processing apparatus 1a, the irradiation unit 14 and the liquid processing unit 15 may be housed in different housings.

[0107] The substrate processing device 1 can be applied to the processing of glass substrates used in flat panel displays (Flat Panel Display: flat panel displays) such as liquid crystal display devices or organic EL (Electro Luminescence) display devices, in addition to semiconductor substrates. In addition, the substrate processing device 1 can also be applied to the processing of optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, photomask substrates, ceramic substrates, and solar cell substrates.

[0108] The configurations in the above-described embodiment and various modifications may be appropriately combined unless they are contradictory to each other.

[0109] The invention has been described in detail above, but the above description is for illustration and not limitation. Therefore, a large number of modifications and aspects are possible without departing from the scope of the invention.

[0110] Description of Reference Numerals

[0111] 1.1a Substrate processing device

[0112] 7.7a Ultraviolet irradiation part

[0113] 9 Substrate

[0114] 31 substrate holding portion

[0115] 31a First substrate holding portion

[0116] 31b Second substrate holding portion

[0117] 51 Nozzle

[0118] 52. Liquid supply unit

[0119] 54 Other liquid supply department

[0120] 62 Irradiation control unit

[0121] 63 Supply Control Department

[0122] 71, 71a Ultraviolet lamp

[0123] 73 Irradiation area scanning mechanism

[0124] 97 Amorphous silicon layer

[0125] 98 Coating

[0126] 512 Nozzle Rotation Mechanism

[0127] 972 Metamorphic Layer

[0128] 981 Sidewall

[0129] Steps S11 to S15

Claims

1. A substrate processing method, comprising the following steps: a) a step of holding a substrate having an amorphous silicon layer on the surface of which a degenerated layer due to dry etching is formed in a horizontal state; b) a step of modifying the degraded layer by irradiating the degraded layer with ultraviolet rays to generate a modified layer; and c) supplying a chemical solution to the amorphous silicon layer having the modified layer on the surface thereof to perform wet etching on the amorphous silicon layer, The amorphous silicon layer is an intermediate pattern formed in the middle of multiple patterning of the substrate. In the dry etching, anisotropic etching is performed on the coating film covering the upper surface and the side surface of the intermediate pattern, so that the upper surface of the intermediate pattern is exposed from the coating film, and the side wall of the coating film covering the side surface of the intermediate pattern is formed. In the wet etching, the intermediate pattern is removed while the sidewall remains.

2. The substrate processing method according to claim 1, in, In the dry etching, the coating film formed on the surface of the amorphous silicon layer is etched using plasma generated using a fluorocarbon-based gas and an oxygen gas.

3. The substrate processing method according to claim 1 or 2, in, The wavelength of the ultraviolet rays is 250 nm or less.

4. The substrate processing method according to claim 1 or 2, in, The cumulative irradiation amount of the ultraviolet rays in the step b) is 1000 mJ / cm 2 above.

5. The substrate processing method according to claim 1 or 2, in, The ultraviolet ray irradiation in the step b) is performed in a low oxygen atmosphere.

6. The substrate processing method according to claim 1 or 2, in, In the step b), the ultraviolet irradiation area on the substrate is scanned. In the amorphous silicon layer, a cumulative irradiation amount of the ultraviolet rays to a region where the altered layer is thick is greater than a cumulative irradiation amount of the ultraviolet rays to a region where the altered layer is thin.

7. The substrate processing method according to claim 1 or 2, in, In the step c), the discharge position of the chemical solution on the substrate is scanned. In the amorphous silicon layer, the discharge time of the chemical solution with respect to a region where the modified layer is thick is longer than the discharge time of the chemical solution with respect to a region where the modified layer is thin.

8. The substrate processing method according to claim 1 or 2, in, Between the step b) and the step c), a step of supplying another chemical solution to the amorphous silicon layer to remove a natural oxide film on the surface of the amorphous silicon layer is further provided.

9. A substrate processing device, wherein include: a substrate holding portion that holds a substrate having an amorphous silicon layer on the surface of which a degenerated layer resulting from dry etching is formed in a horizontal state; an ultraviolet irradiation unit for irradiating ultraviolet rays to the degenerated layer to thereby modify the degenerated layer to generate a modified layer; and a chemical solution supplying unit that supplies a chemical solution to the amorphous silicon layer having the modified layer on the surface thereof to perform wet etching on the amorphous silicon layer, The amorphous silicon layer is an intermediate pattern formed in the middle of multiple patterning of the substrate. In the dry etching, anisotropic etching is performed on the coating film covering the upper surface and the side surface of the intermediate pattern, so that the upper surface of the intermediate pattern is exposed from the coating film, and the side wall of the coating film covering the side surface of the intermediate pattern is formed. In the wet etching, the intermediate pattern is removed while the sidewall remains.

10. The substrate processing apparatus according to claim 9, in, In the dry etching, the coating film formed on the surface of the amorphous silicon layer is etched using plasma generated using a fluorocarbon-based gas and an oxygen gas.

11. The substrate processing apparatus according to claim 9, in, The ultraviolet irradiation to the amorphous silicon layer is performed in a low-oxygen atmosphere.

12. The substrate processing device according to any one of claims 9 to 11, further comprising another chemical solution supply unit, wherein the other chemical solution supply unit supplies other chemical solution to the amorphous silicon layer between the irradiation of the ultraviolet light to the amorphous silicon layer and the supply of the chemical solution, so as to remove the natural oxide film on the surface of the amorphous silicon layer.

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