Substrate processing method

Abstract

The present invention comprises: a first layer formation step of coating a substrate with a first coating liquid containing an organic material and a first photocrosslinking agent to form a first layer 101; a second layer formation step of coating the first layer 101 with a second coating liquid containing a silicon material and a second photocrosslinking agent to form a second layer 102; and a light irradiation step of irradiating a laminate composed of the first layer 101 and the second layer 102 to harden the first layer 101 through a crosslinking reaction to form an organic layer, and to harden the second layer 102 through a crosslinking reaction to form a silicon layer.

Description

[Technical Field]

[0001] The present invention relates to a substrate processing method and a substrate processing apparatus for forming a photoresist layer on a substrate. [Previous Technology]

[0002] In recent years, when etching films on silicon substrates, multilayer films have been used as masking layers to improve etching resistance. For example, Patent Document 1 describes a substrate processing method in which a lower layer film (organic layer) mainly composed of carbon or the like is formed on the film to be processed on the substrate, and ultraviolet light is irradiated onto the lower layer film. In this way, the adhesion between the lower layer film and the photoresist film formed on the lower layer film is improved, and the pattern width that can be generated on the photoresist film can be further reduced.

[0003] Patent Document 2 describes a substrate processing method for forming a carbon-based lower photoresist film (organic layer) on a processed layer on the surface of a substrate. The lower photoresist film is formed by coating a solution of phenolic resin or similar substances in a solvent using a spin coating method, followed by baking with a heating plate or oven. An intermediate film (silicon layer) is formed on the surface of the lower photoresist film by coating a coating material composed of a silicon compound dissolved in a predetermined organic solvent. During the formation of the intermediate film, the coating material on the substrate surface is heated to vaporize the organic solvent. The photoresist film is formed on the surface of the intermediate film.

[0004] Patent Document 3 uses a polymeric compound having vinyl unsaturated bonds that are hardened by a photocrosslinking agent as the lower layer film. That is, the substrate processing method of Patent Document 3 includes the steps of coating a lower layer film forming composition onto a semiconductor substrate to form a coating film, and then forming the lower layer film by irradiating the coating film with light. [Prior Art Documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2021-86993 [Patent Document 2] Japanese Patent Application Publication No. 2002-198295 [Patent Document 3] Japanese Patent Publication No. 4993119 [Summary of the Invention]

[0006] (Problem to be Solved by the Invention) However, in conventional substrate processing methods, where a SOC (Spin on carbon) layer (an organic layer formed by spin coating) and an SOG (Spin on glass) layer (a silicon layer formed by spin coating) are formed below the photoresist layer, the film formation method cannot be considered optimal. Forming the SOC layer, SOG layer, and photoresist layer sequentially on the substrate surface requires many steps. That is, in conventional configurations, each layer is formed by repeatedly forming the SOC layer and then the SOG layer on the substrate surface. Since each layer formation involves a firing process or ultraviolet light irradiation process, the more layers formed on the substrate surface, the more steps are required in the substrate processing. From the viewpoint of power saving and device miniaturization, this substrate processing method is not optimal.

[0007] This invention was made in view of this situation, providing a substrate processing method and substrate processing apparatus that can easily form multiple layers. (Technical means to solve the problem)

[0008] The present invention addresses the aforementioned problems by adopting the following configuration. Specifically, the present invention is a substrate processing method for forming a multilayer structure consisting of an organic layer, a silicon layer, and a photoresist layer on a substrate, characterized by comprising: a first layer forming step of coating a first coating liquid containing an organic material and a first photocrosslinking agent onto a substrate to form a first layer; a second layer forming step of coating a second coating liquid containing a silicon material and a second photocrosslinking agent onto the first layer to form a second layer; a light irradiation step of irradiating the multilayer consisting of the first layer and the second layer with light, causing the first layer to harden through a crosslinking reaction to form the organic layer, and causing the second layer to harden through a crosslinking reaction to form the silicon layer; and a photoresist layer forming step of forming a photoresist layer on the hardened multilayer.

[0009] [Function, Effect] The substrate processing method described above includes: a first layer forming step of coating a substrate with a first coating liquid containing an organic material and a first photocrosslinking agent to form a first layer; a second layer forming step of coating a substrate with a second coating liquid containing a silicon material and a second photocrosslinking agent to form a second layer; and a light irradiation step of irradiating a laminate composed of the first and second layers with light to harden the first layer by a crosslinking reaction to form an organic layer, and to harden the second layer by a crosslinking reaction to form a silicon layer. That is, the substrate processing method of the present invention forms a second layer on a first layer before hardening by a crosslinking reaction, and then irradiates light to harden the first and second layers together to form an organic layer and a silicon layer. According to the present invention, since the first and second layers are hardened together, the formation of multiple layers can be simplified compared to a method that forms an organic layer first and then a second layer. According to the present invention, from the viewpoint of saving power and miniaturizing the device, an optimal substrate processing method can be provided.

[0010] Furthermore, in the above-mentioned substrate processing method, it is preferable that the first layer in the first layer generation step has: a lower layer that becomes the organic layer in the above-mentioned light irradiation step, and a higher layer that disappears by being dissolved by the second coating liquid.

[0011] [Function, Effect] According to the above configuration, the first layer in the first layer formation step has: a lower layer that becomes an organic layer in the light irradiation step, and an upper layer that disappears by dissolving in the second coating liquid. According to this configuration, the configuration of the present invention can be achieved simply by forming a thicker first layer first.

[0012] Furthermore, in the above-described substrate processing method, it is preferable that the solvent of the second coating liquid in the second layer generation step is more difficult to dissolve the organic material than the solvent of the first coating liquid in the first layer generation step.

[0013] [Function, Effect] According to the above configuration, the solvent of the second coating liquid in the second layer formation step is less likely to dissolve organic materials than the solvent of the first coating liquid in the first layer formation step. Based on this configuration, when the second coating liquid is applied to the first layer, the second coating liquid is less likely to dissolve the first layer. Therefore, without needing to pre-calculate the thickness of the layer dissolved by the second coating liquid, a thicker first layer can be formed, thus creating a laminated structure of the first and second layers.

[0014] Furthermore, in the above-mentioned substrate processing method, it is preferable that the second coating liquid in the second layer generation step contains an additive that promotes the dissolution of the silicon material in the solvent.

[0015] [Function, Effect] According to the above configuration, the second coating liquid in the second layer formation step contains an additive that promotes the dissolution of the silicon material in the solvent. With this configuration, a laminated structure of the first and second layers can be easily formed.

[0016] Furthermore, in the above substrate processing method, it is preferable that the light irradiated in the above light irradiation step is any ultraviolet light with a wavelength of 172 nm to 385 nm.

[0017] [Function, Effect] According to the above configuration, the light irradiated in the light irradiation step is any wavelength from 172 nm to 385 nm. If the light irradiated in the light irradiation step is ultraviolet light, the first layer and the second layer can reliably become an organic layer and a silicon layer.

[0018] Furthermore, in the above-mentioned substrate processing method, it is preferable that: the silicon layer is illuminated by light in the above-mentioned light irradiation step so that the irradiated light reaches the first layer.

[0019] [Function, Effect] According to the above configuration, the silicon layer allows the irradiated light to reach the first layer during the light irradiation step. With this configuration, it is possible to prevent the irradiated light during the light irradiation step from being absorbed by the silicon layer and failing to reach the first layer, thus ensuring that the first layer is reliably an organic layer.

[0020] Furthermore, the above-described substrate processing method preferably includes: a first firing step, which removes the solvent contained in the first layer after the first layer formation step and before the second layer formation step; and a second firing step, which removes the solvent contained in the second layer after the second layer formation step and before the light irradiation step.

[0021] [Function, Effect] According to the above configuration, a first firing step is provided after the first layer formation step and before the second layer formation step to remove the solvent contained in the first layer. With this configuration, the first layer can be reliably dried, thus facilitating the formation of the organic layer. Furthermore, according to the above configuration, a second firing step is provided after the second layer formation step and before the light irradiation step to remove the solvent contained in the second layer. With this configuration, the second layer can be reliably dried, thus facilitating the formation of the silicon layer.

[0022] Furthermore, in the above-mentioned substrate processing method, it is preferred that: the first firing step is performed at a temperature of 100°C to 150°C; and the second firing step is performed at a temperature of 100°C to 150°C.

[0023] [Function, Effect] According to the above configuration, the first firing step fires the substrate at any temperature from 100°C to 150°C. If the first firing step is set to low-temperature firing, a power-saving substrate processing method can be provided. Furthermore, according to the above configuration, the second firing step fires the substrate at any temperature from 100°C to 150°C. If the second firing step is set to low-temperature firing, a power-saving substrate processing method can be provided.

[0024] Furthermore, this specification also discloses an invention related to the following substrate processing apparatus. That is, this specification discloses a substrate processing apparatus for forming a laminate structure consisting of an organic layer, a silicon layer, and a photoresist layer on a substrate, characterized by comprising: a first chamber for forming a first layer by supplying a first liquid containing at least an organic material and a first photocrosslinking agent to the substrate; a second chamber for forming a second layer by supplying a second liquid containing at least a silicon material and a second photocrosslinking agent to the first layer; a light irradiation chamber for irradiating the laminate consisting of the first layer and the second layer with light, causing the first layer to harden into an organic layer through a crosslinking reaction, and causing the second layer to harden into a silicon layer through a crosslinking reaction; and a third chamber for forming a photoresist layer on the silicon layer.

[0025] [Function, Effect] The substrate processing apparatus described above includes: a first chamber for forming a first layer by supplying a first liquid containing at least an organic material and a first photocrosslinking agent to a substrate; a second chamber for forming a second layer by supplying a second liquid containing at least a silicon material and a second photocrosslinking agent to the first layer; a light irradiation chamber for irradiating a laminate composed of the first and second layers with light, thereby hardening the first layer into an organic layer by a crosslinking reaction and hardening the second layer into a silicon layer by a crosslinking reaction; and a third chamber for forming a photoresist layer on the silicon layer. According to the present invention, since the first and second layers are hardened together, the formation of multiple layers can be simplified compared to the method of forming the second layer after forming the organic layer. According to the present invention, from the viewpoint of saving power and miniaturizing the device, an optimal substrate processing apparatus can be provided. (Effects compared to prior art)

[0026] According to the present invention, a substrate processing method and a substrate processing apparatus that can easily form multiple layers can be provided.

Implementation Method

[0028] Embodiments of the present invention will be described below with reference to the accompanying drawings. The photolithography apparatus of the embodiments includes: a stepper for performing exposure processing on the surface of a substrate having a front and a back side; and a substrate processing apparatus for performing necessary substrate processing before and after the exposure processing. The substrate processing apparatus of the present invention relates to a substrate processing method for forming a multilayer structure composed of an organic layer, a silicon layer, and a photoresist layer on a substrate. [Embodiment]

[0029] 1. Overall Structure Figure 1 is a top view showing the overall structure of the photolithography apparatus of this example. The photolithography apparatus of this example is a structure consisting of a substrate processing device 1 and a stepper 2 connected together. The substrate processing device 1 further includes an indexer block 3, a coater block 5, a developer block 7, and an interface block 9. The indexer block 3, the coater block 5, the developer block 7, and the interface block 9 are arranged in this order to form the substrate processing device 1. The substrate processing device 1 has a frame 1A for housing each block. The frame 1A is slightly rectangular in shape when viewed from above. A loading port 11 is provided on the wall of one end of the frame 1A.

[0030] In this specification, for convenience, the direction in which the indexer block 3, coater block 5, developer block 7, and interface block 9 are arranged in the substrate processing apparatus 1 is referred to as the front-back direction (X direction). This X direction extends horizontally. The direction from the coater block 5 toward the indexer block 3 in the substrate processing apparatus 1 is referred to as the front. The direction opposite to the front is referred to as the rear. The horizontal direction orthogonal to the X direction is referred to as the left-right direction (Y direction). The Y direction is also the direction in which the plurality of loading ports 11 are arranged. For convenience, one side of the Y direction is referred to as the right. The direction opposite to the right is referred to as the left. The height direction (Z direction) is orthogonal to both the X and Y directions and is consistent with the vertical direction. Front, rear, right, left, up, and down are appropriately indicated in the figures for reference.

[0031] 2. As shown in Figure 1, the indexer block 3 includes a loading port 11 that serves as an inlet when a carrier C, which stores multiple substrates W in a horizontal position at predetermined intervals in the Z direction, is inserted into the block. The loading port 11 can hold the carrier C.

[0032] A plurality of substrates W (e.g., 25) are stacked and stored in a carrier C. The carrier C, which holds the unprocessed substrates W, is first placed on the loading port 11 and then transported into the substrate processing apparatus 1.

[0033] An indexer robot IR is configured in indexer block 3 to transport substrates W in a horizontal orientation one at a time. The indexer robot IR can access the conveyor 34 and the four loading ports 11 located at the boundary between indexer block 3 and coater block 5 as shown in FIG. 1. The substrates W are transferred between the conveyor 34 and the carrier C provided at the loading ports 11. The transfer of substrates W by the indexer robot IR is achieved by the hand 36.

[0034] 3. Coating Block The coating block 5 is mainly used to form a photoresist layer on the substrate W before exposure processing. The coating block 5 has: a second column CL2 located after the conveyor 34; a first column CL1 located to the left of the second column CL2; and a third column CL3 located to the right of the second column CL2. Thus, the second column CL2 is positioned by being held from the left and right by the first column CL1 and the third column CL3.

[0035] In column CL1, there is a liquid treatment chamber arranged in the X direction, which includes a rotating clamp 8 that rotatably supports the substrate W and a nozzle 10 for dispensing liquid. Thus, the liquid treatment chamber is configured to coat the liquid onto the surface of the substrate W. In the liquid treatment chamber, there is a lower film-forming chamber 51 for forming a SOC (Spin on carbon) layer (organic layer) and an SOG (Spin on glass) layer (silicon layer), and a photoresist chamber 53 for forming a photoresist layer. The SOC layer corresponds to the organic layer of the present invention, and the SOG layer corresponds to the silicon layer of the present invention. In column CL1 of FIG1, the case in which two photoresist chambers 53 or two lower film-forming chambers 51 are arranged one after the other is explained. In column CL1, the lower film-forming chambers 51 and the photoresist chambers 53 are deposited. The lower film-forming chamber 51 and the photoresist chamber 53 can be interchanged in their vertical relationship. Also, in the first column CL1, the drug treatment chamber can be set to three or more layers.

[0036] The lower film-forming chamber 51 corresponds to the first and second chambers of the present invention. It can spin-coat the film-forming related pharmaceutical solution onto the substrate W via the nozzle 10, and can also perform spin drying to dry the coated pharmaceutical solution. The lower film-forming chamber 51 can selectively spin-coat the substrate W with a high molecular weight aromatic compound dissolved in PGMEA (Propylene glycol monomethyl ether acetate), or a silicone compound dissolved in PGMEA. The high molecular weight aromatic compound corresponds to the organic material of the present invention, and the silicone compound corresponds to the silicone material of the present invention. The solvent constituting the pharmaceutical solution is not limited to PGMEA, but can also be, for example, PGME (Propylene glycol monomethyl ether). The pharmaceutical solution containing the high molecular weight aromatic compound is called the first coating solution. The first coating solution is a pharmaceutical solution for SOC film formation. On the other hand, the pharmaceutical solution containing the silicone compound is called the second coating solution. The second coating solution is a solution used for SOG film formation. Furthermore, both the first and second coating solutions contain a photocrosslinking agent that causes the polymer compounds to crosslink and harden. When the photocrosslinking agent is irradiated with ultraviolet light, it causes different polymers to crosslink and polymerize, forming a network structure composed of polymers. For example, a photoradical polymerization initiator can be used as the photocrosslinking agent. The photocrosslinking agent added to the first coating solution is the first photocrosslinking agent, and the photocrosslinking agent added to the second coating solution is the second photocrosslinking agent. Additionally, the lower film-forming chamber 51 can also be cleaned by rotating the substrate W using a rinsing solution, such as pure water.

[0037] The photoresist chamber 53, in addition to photoresist layer deposition, can perform edge exposure related to photoresist layer removal at the periphery of the substrate W. Edge exposure does not necessarily have to be performed in the photoresist chamber 53; it can also be achieved by an edge exposure section separately provided from the photoresist chamber 53. The edge exposure section is provided in the third column CL3 described later, or the sixth column CL6 in the developer block 7 described later.

[0038] The second column CL2 serves as a pathway for the first central robot CR1 to move back and forth while transporting the substrate W in a horizontal position. In addition to the aforementioned conveyor 34, the first central robot CR1 can also access the lower layer film-forming chamber 51, photoresist chamber 53, heat treatment chamber 55 located after the third column CL3, cooling section 58, and the conveyor 54 located at the boundary between the coater block 5 and the developer block 7 shown in FIG1.

[0039] The first central robot CR1 can move freely forward and backward in the X direction and move freely up and down in the Z direction, and can transport the substrate W to various accessible positions. Moreover, the first central robot CR1 can also make the hand 56 holding the substrate W face any direction, forward, backward, left or right.

[0040] In the third column CL3, the heat treatment chamber 55 for heating the substrate W, the cooling section 58 for cooling the substrate W, and the light irradiation chamber 61 for irradiating the substrate W with ultraviolet light are arranged in the X direction. The ultraviolet light is equivalent to the light of the present invention. In the heat treatment chamber 55, a circular heating plate 55a for heating the substrate W and a circular post-heating treatment plate 55b for performing post-heating treatment to reduce the temperature of the substrate W which will become high temperature are arranged in the Y direction. On the other hand, a circular cooling treatment plate 58a for cooling the room temperature substrate W is provided in the cooling section 58. In the third column CL3, the heat treatment chamber 55, the cooling section 58, or the light irradiation chamber 61 are not only arranged in the X direction, but also constitute a laminate of chambers stacked in the Z direction. The number of layers in the laminate can be appropriately changed.

[0041] 4. Light Irradiation Chamber Figure 2 illustrates the structure of the light irradiation chamber 61 in this example. The light irradiation chamber 61 includes: a base plate 61a supporting the substrate W; a cover member 12 having an opening 26 blocked by the base plate 61a; and an annular sealing member 20 located between the base plate 61a and the cover member 12. The sealing member 20 is fixed to the base plate 61a.

[0042] The base plate lifting mechanism 23 causes the base plate 61a to rise and fall, which is equivalent to the cover member 12. The base plate 61a can be in two states by means of the base plate lifting mechanism 23: the state shown in Figure 2 in which the sealing member 20 is tightly adhered to the opening 26 of the cover member 12; and the state shown in Figure 3 in which the sealing member 20 is separated from the opening 26 of the cover member 12.

[0043] The cover member 12 and the base plate 61a are robust enough to make the internal space surrounded by the cover member 12, the base plate 61a, and the sealing member 20 a vacuum. Degassing of this internal space is achieved by an exhaust section 24 constructed using a vacuum pump. An exhaust pipe 18 connects the exhaust section 24 to the internal space of the cover member 12. On the other hand, gas supply to the vacuum-state internal space is achieved by an air supply section 25. An air supply pipe 19 connects the air supply section 25 to the internal space of the cover member 12. Figure 2 shows the light irradiation chamber 61 where the internal space of the cover member 12 is in a vacuum state.

[0044] Figure 3 shows the light irradiation chamber 61 in a state where a horizontally positioned substrate W can enter and exit by separating the base plate 61a from the cover member 12. As shown in Figure 3, a through hole 16 extending in the vertical direction is provided in the base plate 61a. Each through hole 16 is provided with a top pin 13 that can freely enter and exit relative to the base plate 61a. The number of top pins 13 is, for example, 3. The top pins 13 enter and exit relative to the base plate 61a with their front ends at a uniform height. The substrate W, which is transported to the light irradiation chamber 61 by the first central robot CR1, is held by the front ends of the extended top pins 13.

[0045] A fixing pin 17 for holding the substrate W is provided on the top of the base plate 61a. The number of fixing pins 17 is, for example, four. In Figures 2 and 3, two are shown for ease of drawing. The fixing pins 17 are configured to hold the substrate W when the top pin 13 is in the retracted state as shown in Figure 2. Thus, in this example, when the base plate 61a is below and the internal space of the cover member 12 is connected to the outside air, the substrate W is supported by the extended top pin 13 in the light irradiation chamber 61. On the other hand, in this example, when the base plate 61a is above and the internal space of the cover member 12 is isolated from the outside air, the substrate W is not supported by the retracted top pin 13, but by the fixing pin 17.

[0046] A light source 15 capable of irradiating ultraviolet light is attached to the top plate of the cover member 12 constituting the upper part of the interior space. The light source 15 can be, for example, a series of vertically and horizontally arranged UVLEDs (Ultraviolet Light Emitting Diodes), or a xenon lamp or a mercury lamp. When the light source 15 is a UVLED, the wavelength of the ultraviolet light irradiated by the light source 15 is 385 nm. When the light source 15 is a xenon lamp or a mercury lamp, the wavelengths of the ultraviolet light irradiated by the light source 15 are 172 nm and 365 nm, respectively. Thus, a wavelength of ultraviolet light irradiated by the light source 15 of 172 nm to 385 nm, i.e., 400 nm or less, is appropriate. Furthermore, the ultraviolet light irradiation dose is preferably 200 mJ / cm² or more. These details will be described later.

[0047] The light source control unit 21 is configured to control ultraviolet light irradiation by controlling whether to supply power to the light source 15. The light source control unit 21 irradiates ultraviolet light by the light source 15 while keeping the internal space of the cover member 12 a vacuum.

[0048] The sealing member 14 is located below the base plate 61a at the position of blocking the through hole 16, which allows the top pin 13 to move freely back and forth, while ensuring the sealing of the internal space so that external air does not enter the internal space of the cover member 12 through the through hole 16.

[0049] Explanation of the operation of the light irradiation chamber 61. In the initial state, as shown in FIG3, the base plate 61a is located below and the top pin 13 is extended. The first central robot CR1 can insert its hand 56 into the gap between the cover member 12 and the base plate 61a, and can move the unprocessed substrate W to the front end of the top pin 13, and can also obtain the processed substrate W placed on the front end of the top pin 13 and move it out of the light irradiation chamber 61.

[0050] When the substrate W is irradiated with ultraviolet light, firstly, the sealing member 20 is tightly adhered to the underside of the cover member 12 by raising the base plate 61a. Then, as shown in FIG2, the substrate W is handed over to the fixing pin 17 by the top pin 13 being in a retracted state.

[0051] Subsequently, the exhaust section 24 actuates to make the internal space of the cover member 12 a vacuum state. The light source control section 21 then irradiates ultraviolet light toward the substrate W.

[0052] Once the ultraviolet irradiation treatment is complete, the gas supply unit 25 actuates to make the pressure inside the cover member 12 the same as the outside air. Then, the base plate 61a moves downwards, as shown in Figure 3, and the top pin 13 extends, allowing the substrate W supported by the fixing pin 17 to be picked up by the top pin 13. The first central robot CR1 can then remove the substrate W picked up by the top pin 13 from the light irradiation chamber 61.

[0053] 5. Developer Block The developer block 7 is mainly configured to develop the exposed substrate W. The developer block 7 has: a 5th column CL5 located after the conveyor 54; a 4th column CL4 located to the left of the 5th column CL5; and a 6th column CL6 located to the right of the 5th column CL5. Thus, the 5th column CL5 is positioned by being held from the left and right by the 4th column CL4 and the 6th column CL6.

[0054] In column 4 (CL4), there are developing chambers 71 arranged in the X direction, which have a rotating clamp 8 that rotatably supports the substrate W and a nozzle 10 for dispensing the chemical solution. In column 4 (CL4) of FIG1, the arrangement of two developing chambers 71 arranged one in front of the other is explained. In column 4 (CL4), the developing chambers 71 are laminated. The number of layers in the laminate formed by the developing chambers 71 can be appropriately changed.

[0055] The fifth column CL5 serves as a passageway for the second central robot CR2 to move back and forth while transporting the substrate W in a horizontal position. In addition to the aforementioned conveyor 54, the second central robot CR2 can also access the developing chamber 71 of the fourth column CL4, the heat treatment chamber 75 located after the sixth column CL6, the cooling section 78, and the conveyor 74.

[0056] The second central robot CR2, like the first central robot CR1, can move freely forward and backward in the X direction and rise and fall freely in the Z direction, and can transport the substrate W to various accessible positions. Moreover, the second central robot CR2 can also position the hand 76 holding the substrate W in at least any of the following directions: forward, left, or right.

[0057] In the 6th column CL6, the heat treatment chamber 75 of the heating substrate W and the cooling section 78 of the cooling substrate W are arranged in the X direction. The heat treatment chamber 75 has the same configuration as the heat treatment chamber 55 in the 3rd column. Therefore, the heat treatment chamber 75 is configured such that a circular heating plate 75a and a circular post-heating treatment plate 75b are arranged in the Y direction. The cooling section 78 has the same configuration as the cooling section 58 in the 3rd column CL3. Therefore, a circular cooling plate 78a is provided in the cooling section 78.

[0058] The transmitter 74 is located at the end after the 6th column CL6. The horizontally positioned substrate W can move back and forth between the developer block 7 and the interface block 9 via the transmitter 74.

[0059] 6. Interface Block Interface block 9 includes: a transmitter 94 capable of cooling the substrate W it is placed on; a first robot R1 capable of accessing the transmitter 94 and the aforementioned transmitter 74; and a second robot R2 capable of accessing the transmitter 94 and the stepper 2. The first robot R1 has a hand 961 capable of holding the substrate W placed in a horizontal position on the transmitter 74, and the second robot R2 has a hand 962 capable of holding the substrate W placed in a horizontal position on the transmitter 94.

[0060] The transmitter 94 is stacked in the Z direction to form a stacked body.

[0061] 6. Stepper 2 receives the substrate W before exposure processing, which is transported by the second robot R2, performs exposure processing, and prints the circuit pattern of the photoresist layer on the substrate W. The substrate W after exposure processing is delivered to the second robot R2.

[0062] 7. Control Unit As shown in FIG1, the substrate processing apparatus 1 includes a control unit 131 related to device control. Although not shown in FIG1, a corresponding memory unit is provided in the control unit 131. The control unit 131 is configured, for example, by a CPU (Central Processing Unit). The specific configuration of the control unit is not limited; for example, each control of the substrate processing apparatus 1 may be configured by a single processor, or each control may be configured by individual processors.

[0063] The control related to the control unit 131 may be, for example, the control related to the indexer robot IR, the first central robot CR1, the second central robot CR2, the first robot R1, or the second robot R2.

[0064] The memory unit stores programs or parameters related to control. The control unit may be composed of a single device or individual devices corresponding to each control. Otherwise, in the substrate processing apparatus 1 of this example, there is no particular limitation on the configuration of the device that implements the memory unit.

[0065] 8. Film Formation Process Figure 4 is a flowchart illustrating the process of forming the SOC layer, SOG layer and photoresist layer on the substrate W by the coating block 5 in this example. The film formation process of each layer will be described below with reference to Figure 4.

[0066] Step S11: The substrate W stored in the carrier C is transported to the lower film-forming chamber 51 of the coater block 5 via the indexer block 3. The indexer robot IR transports the substrate W stored in the carrier C to the conveyor 34 via the coater block 5. The first central robot CR1 transports the substrate W held by the conveyor 34 to the lower film-forming chamber 51. The lower film-forming chamber 51 rotatably supports the substrate W via the rotating clamp 8.

[0067] Figure 5 is a cross-sectional view illustrating the structure of the substrate W housed in the carrier C. The substrate W has: a base 100 having a thickness when cut from a silicon ingot; and a processed layer 103 provided on the base 100. On the substrate W, the surface having the processed layer 103 is surface F, and the surface not having the processed layer 103 is back surface B. Surface F is the device surface of the forming apparatus in the substrate W.

[0068] The processed layer 103 is composed of, for example, a conductive material such as a metal film, or an insulating material such as silicon oxide. The processed layer 103 is a film for which the processing purpose is to be partially removed by etching in photolithography.

[0069] Step S12: After the substrate W is rotated by the rotating fixture 8, the nozzle 10 rotates so that the front end of the nozzle 10 is positioned on the substrate W. In this state, the nozzle 10 dispenses the first coating liquid toward the substrate W. The first coating liquid spreads from the center of the rotating substrate W toward the outside of the substrate W, covering the surface F of the substrate W. When the first coating liquid has fully covered the substrate W, the nozzle 10 stops dispensing the first coating liquid.

[0070] Step S13: Dry the solvent of the first coating liquid on the surface of the substrate W. The drying of the first coating liquid can be carried out by natural drying or by rotary drying. The first coating liquid is dried on the surface of the substrate W to form a first layer. The first layer is composed of high molecular weight aromatic compounds and photocrosslinking agents contained in the first coating liquid.

[0071] Figure 6 illustrates the first layer 101 generated in step S13. As shown in Figure 6, the first layer 101 is coated on top of the processed layer 103. The first layer 101 has a lower layer 101a that becomes the SOC layer in the subsequent light irradiation step (step S16 in Figure 4), and a higher layer 101b that disappears in the subsequent step (step S14 in Figure 4) by being dissolved by the second coating liquid. That is, the higher layer 101b is dissolved by the second coating liquid, and the substrate W is rotated to disperse it, thereby reducing the film thickness of the first layer 101. Based on this meaning, the higher layer 101b can be considered as a film that disappears by the subsequent substrate processing. The film thickness of the first layer 101 is, for example, about 200 nm. The film thickness of the first layer 101 can be appropriately changed by adjusting the rotation speed of the rotating jig 8 in step S12.

[0072] Steps S12 and S13 described above correspond to the first film-forming step of the present invention. Steps S12 and S13 are steps of coating a first coating liquid containing an organic material and a first photocrosslinking agent onto a substrate to form a first layer 101. The lower film-forming chamber 51 is formed by supplying a first coating liquid containing at least the above-described organic material and the first photocrosslinking agent onto the substrate to form the first layer 101.

[0073] Step S14: Nozzle 10 dispenses the second coating liquid toward substrate W. The second coating liquid spreads from the center of the rotating substrate W toward the outside of substrate W, covering the surface F of substrate W. When the second coating liquid has fully covered substrate W, nozzle 10 stops dispensing the second coating liquid.

[0074] Step S15: Dry the solvent of the second coating liquid on the surface of the substrate W. The drying of the second coating liquid can be achieved either by natural drying or, as in this example, by rotary drying. The second coating liquid is dried on the surface of the substrate W to form a second layer. The second layer is composed of the polysilicon compound contained in the second coating liquid and the second photocrosslinking agent. The lower film-forming chamber 51 is formed by supplying the second coating liquid, containing at least silicon material and the second photocrosslinking agent, onto the substrate to generate the second layer 102.

[0075] Steps S14 and S15 described above correspond to the second film-forming step of the present invention. Steps S14 and S15 involve coating the first layer 101 with a second coating liquid containing silicon material and a second photocrosslinking agent to form the second layer 102. The lower film-forming chamber 51 is formed by supplying the substrate with a second coating liquid containing at least the aforementioned silicon material and second photocrosslinking agent to form the second layer 102.

[0076] Figure 7 illustrates the second layer 102 generated in step S15. As shown in Figure 7, the second layer 102 covers the lower layer 101a of the first layer 101. In step S14, when the second coating liquid is supplied to the substrate W through the nozzle 10, the upper layer 101b of the first layer 101 on the surface F of the substrate W is dissolved by the solvent contained in the second coating liquid. This part is dispersed and disappears due to the rotation of the substrate W.

[0077] In step S15, when the solvent drying of the second coating solution begins, the dissolution of the first layer 101 by means of the second coating solution stops. This is because, apart from stopping the supply of new second coating solution, the solvent that causes the erosion of the first layer 101 disappears from the surface of the substrate W by drying. The film thickness of the second layer 102 is, for example, about 10 nm to 35 nm. The film thickness of the second layer 102 can be appropriately changed by adjusting the rotation speed of the rotating jig 8 in step S14. On the other hand, the film thickness of the first layer 101 (lower layer 101a) remaining on the surface of the substrate W is, for example, about 60 nm to 100 nm. The film thickness of the lower layer 101a in the first layer 101 can be appropriately changed by adjusting the supply amount of the second coating solution in step S14.

[0078] Step S16: The substrate W of the second layer 102 is formed on the surface F and is transported to the light irradiation chamber 61 by the first central robot CR1.

[0079] Step S17: Irradiate the substrate W with ultraviolet light. Thus, as shown in FIG8, the first layer 101 (lower layer 101a) is hardened by a polymerization reaction to become the SOC layer 105 (organic layer). Similarly, the second layer 102 is hardened by a polymerization reaction to become the SOG layer 106 (silicon layer). Thus, in this example, the SOC layer 105 and the SOG layer 106 can be formed simultaneously by a single ultraviolet light irradiation. Step S17 corresponds to the light irradiation step of the present invention. Step S17 involves irradiating the laminate composed of the first layer 101 and the second layer 102 with ultraviolet light, causing the first layer 101 to harden into the SOC layer 105 through a crosslinking reaction, and causing the second layer 102 to harden into the SOG layer 106 through a crosslinking reaction.

[0080] Thus, in step S17, the SOG layer 106 is formed by ultraviolet light irradiated by the light source 15 (see Figure 2) reaching the first layer 101. This ensures that the first layer 101 is solidified into the SOC layer 105. The light irradiation chamber 61 irradiates the laminate composed of the first layer 101 and the second layer 102 with ultraviolet light, causing the first layer 101 to solidify into the SOC layer 105 through a crosslinking reaction, and causing the second layer 102 to solidify into the SOG layer 106 through a crosslinking reaction.

[0081] Step S18: Subsequently, the substrate W is transferred to the photoresist chamber 53 for photoresist layer deposition. FIG9 illustrates the photoresist layer 107 thus formed. As shown in FIG9, on the surface F of the substrate W before exposure processing, on the substrate 100, the processed layer 103, the SOC layer 105, the SOG layer 106, and the photoresist layer 107 are sequentially deposited. The thickness of the photoresist layer 107 is, for example, 35 nm to 60 nm. Step S18 corresponds to the photoresist layer formation step of the present invention. Step S18 involves forming a photoresist layer on the hardened laminate. The photoresist chamber 53 corresponds to the third chamber of the present invention. The photoresist chamber 53 forms the photoresist layer 107 on the SOG layer 106. Thus, the film deposition process of the substrate W in this example is completed.

[0082] 9. Appropriate UV irradiation amount. The appropriate UV irradiation amount in step S17 is preferably 200 mJ / cm2. Figure 10 shows the experimental results of appropriate UV irradiation amount. The black dots in Figure 10 indicate the degree of reduction of the first layer 101 after UV treatment with various irradiation amounts under different conditions, without the formation of the second layer 102, and when a PGME / PGMEA mixed solution (PGME:PGMEA ratio = 7:3) is spin-coated without firing treatment. Also, for comparison, 0 in the graph also represents the reduction rate without UV treatment. According to the graph, if the UV irradiation amount is 200 mJ / cm2 or higher, the first layer 101 is sufficiently hardened.

[0083] The white dots in Figure 10 indicate the degree of reduction in the first layer 101 after the second layer 102 is formed on the substrate and subjected to ultraviolet light treatment under various irradiation doses under different conditions, without firing, when a PGME / PGMEA mixed solution (PGME:PGMEA ratio = 7:3) is spin-coated. Furthermore, for comparison, 0 in the graph also represents the reduction rate without ultraviolet light treatment. According to the graph, if the ultraviolet irradiation dose is 200 mJ / cm² or higher, the second layer 102 is sufficiently hardened. The characteristic of this example is that the first layer 101 and the second layer 102 are hardened by a single ultraviolet irradiation, preferably at a dose of 200 mJ / cm² or higher. Experiments show that this irradiation dose is sufficient for the hardening of the first layer 101 and the second layer 102.

[0084] 10. Substrate Processing Flow Next, the substrate processing flow of this example will be described with reference to the flowchart in FIG11.

[0085] Step T11: The unprocessed substrate W stored in the carrier C is transported to the conveyor 34 by the indexer robot IR.

[0086] Step T12: The first central robot CR1 in the coating block 5 transports the substrate W obtained by the conveyor 34 to the cooling section 58. The substrate W is cooled by the cooling section 58.

[0087] Step T13: The first central robot CR1 transports the substrate W of the cooling section 58 to the lower film deposition chamber 51. The substrate W undergoes film deposition processing of the first layer 101 (lower layer 101a) and the second layer 102 in the lower film deposition chamber 51.

[0088] Step T14: The first central robot CR1 transports the substrate W from the lower film deposition chamber 51 to the light irradiation chamber 61. The substrate W is subjected to ultraviolet light irradiation treatment by the light irradiation chamber 61.

[0089] Step T15: The first central robot CR1 transports the substrate W from the heat treatment chamber 55 to the photoresist chamber 53. The substrate W undergoes photoresist layer deposition in the photoresist chamber 53.

[0090] Step T16: The first central robot CR1 transports the substrate W from the photoresist chamber 53 to the heat treatment chamber 55. The substrate W undergoes heat treatment in the heat treatment chamber 55.

[0091] Step T17: The first central robot CR1 transports the substrate W from the heat treatment chamber 55 to the conveyor 54. Thus, the substrate W with the photoresist layer formed exits from the coater block 5.

[0092] Step T18: The second central robot CR2 in the developer block 7 transports the substrate W of the conveyor 54 to the conveyor 74.

[0093] Step T19: The first robot R1 in interface block 9 transports the substrate W of transmitter 74 to transmitter 94.

[0094] Step T31: The second robot R2 transports the substrate W of the transmitter 94 to the stepper 2. The stepper 2 exposes the circuit pattern of the necessary device for the substrate W using a mask.

[0095] Step T32: The second robot R2 obtains the substrate W after exposure processing from the stepper 2 and transports it to the conveyor 94.

[0096] Step T33: The first robot R1 transports the substrate W from the conveyor 94 to the conveyor 74. Thus, the substrate W after exposure processing exits from the interface block 9.

[0097] Step T34: The second central robot CR2 in the developer block 7 transports the substrate W from the conveyor 74 to the cooling section 78. The substrate W is cooled in the cooling section 78.

[0098] Step T35: The second central robot CR2 transports the substrate W of the cooling section 78 to the developing chamber 71. The substrate W undergoes developing treatment in the developing chamber 71.

[0099] Step T36: The second central robot CR2 transports the substrate W from the developing chamber 71 to the heat treatment chamber 75. The substrate W undergoes heat treatment in the heat treatment chamber 75.

[0100] Step T37: The second central robot CR2 transports the substrate W from the heat treatment chamber 75 to the conveyor 54. Thus, the substrate W, after development, exits from the developer block 7.

[0101] Step T38: The first central robot CR1 in the coater block 5 transports the substrate W from the conveyor 54 to the conveyor 34. Thus, the substrate W, after development, exits from the coater block 5. The substrate W in the conveyor 34 is returned to its original carrier C by the indexer robot IR.

[0102] 11. Effects of the present invention: Based on the above configuration, the present invention comprises: steps S12 and S13 of forming a first layer 101 by coating a first coating liquid containing an organic material and a first photocrosslinking agent onto a substrate; steps S14 and S15 of forming a second layer 102 by coating a second coating liquid containing a silicon material and a second photocrosslinking agent onto the first layer 101; and a light irradiation step of irradiating the laminate composed of the first layer 101 and the second layer 102 to harden the first layer 101 into a SOC layer 105 by a crosslinking reaction and to harden the second layer 102 into an SOG layer 106 by a crosslinking reaction. That is, the substrate processing method of this example forms a second layer 102 from the first layer 101 before hardening by a crosslinking reaction, and hardens the first layer 101 and the second layer 102 at one time by irradiation to form the SOC layer 105 and the SOG layer 106, respectively. In this example, since the first layer 101 and the second layer 102 are cured together, the formation of multiple layers is simplified compared to the method of forming the second layer 102 after forming the SOC layer 105. From the viewpoint of power saving and device miniaturization, this example provides an optimal substrate processing method.

[0103] According to the above configuration, the first layer 101 in the first layer formation step has: a lower layer 101a that becomes the SOC layer 105 in the light irradiation step; and an upper layer 101b that is dissolved and disappeared by the second coating liquid. If configured in this way, the configuration of this example can be achieved simply by forming the first layer 101 into a thicker film beforehand.

[0104] According to the above configuration, the light irradiated in the light irradiation step is any wavelength from 172 nm to 385 nm. If the light irradiated in the light irradiation step is set to ultraviolet light, the first layer 101 and the second layer 102 can reliably become the SOC layer 105 and the SOG layer 106.

[0105] According to the above configuration, the SOG layer 106 is used in the light irradiation step to allow the irradiated light to reach the first layer 101. With this configuration, it is possible to prevent the irradiated light in the light irradiation step from being absorbed by the SOG layer 106 and not reaching the first layer 101, and the first layer 101 can be reliably made into the SOC layer 105.

[0106] The substrate processing apparatus described above includes: a lower layer film-forming chamber 51 on which a first coating liquid containing at least an organic material and a first photocrosslinking agent is supplied to form a first layer 101; a lower layer film-forming chamber 51 on which a second coating liquid containing at least a silicon material and a second photocrosslinking agent is supplied to form a second layer 102; a light irradiation chamber on which ultraviolet light is irradiated onto a laminate composed of the first layer 101 and the second layer 102, causing the first layer 101 to harden into a SOC layer 105 by a crosslinking reaction, and causing the second layer 102 to harden into an SOG layer 106 by a crosslinking reaction; and a photoresist chamber 53 on which a photoresist layer is formed on the SOG layer 106. In this example, since the first layer 101 and the second layer 102 are hardened together, the film-forming of multiple layers is simplified compared to the method of forming the second layer 102 after forming the SOC layer 105. Based on this example, from the perspective of power saving and device miniaturization, the best substrate processing device can be provided.

[0107] 12. Modified embodiments of the present invention The present invention is not limited to the above-described configuration and can be modified as follows.

[0108] <Modification 1> According to the above configuration, the solvent of the second coating liquid is PGMEA or PGME, but the present invention is not limited to this configuration. The solvent of the second coating liquid may also be a substance that is less soluble than PGMEA. For example, MIBC (methyl isobutyl carbinol) or water may be selected as the solvent of the second coating liquid. According to this modification, the solvent of the second coating liquid is an organic material that is less soluble than the solvent of the first coating liquid. If configured in this way, when the second coating liquid is coated on the first layer 101, the second coating liquid does not easily dissolve the first layer 101. Therefore, the first layer 101 can be formed thicker without prior estimation of the thickness of the layer dissolved by the second coating liquid, and a laminated structure of the first layer 101 and the second layer 102 can be generated.

[0109] Furthermore, according to this modified example, the dissolution of the upper layer 101a in the first layer 101 can also be suppressed. This is because the ability of the poorly soluble solvent to dissolve the first layer 101 is lower than that of PGMEA and the like. This situation can suppress the dissolution of the first layer 101 due to the second coating liquid, which is therefore preferable. However, in the method of this modified example, sometimes a mixing layer of the first layer 101 and the second layer 102 occurs at the interface between the first layer 101 and the second layer 102. The mixing layer may hinder exposure or etching. Therefore, it is preferable to dry the first layer 101 in advance by firing step to prevent the mixing layer from occurring.

[0110] <Modification 2> An additive that promotes the dissolution of the silicon material in the solvent can also be added to form a second coating liquid. As an additive, PVDF (polyvinylidene fluoride) can be used, for example. If configured in this way, a laminated structure of the first layer 101 and the second layer 102 can be easily formed.

[0111] <Modification 3> According to the above configuration, the solvent contained in the first layer 101 is removed by natural drying or rotary drying, but the present invention is not limited to this configuration. That is, it can be configured to have a first firing step to remove the solvent contained in the first layer 101 after step S12 and before step S14. According to this configuration, since the first layer 101 can be dried reliably, the SOC layer 105 is easily generated. The first firing step is implemented by the heat treatment chamber 55 shown in FIG1. ​​The substrate W is transferred from the lower film-forming chamber 51 to the heat treatment chamber 55 by the first central robot CR1. Furthermore, the substrate W after firing is transferred from the heat treatment chamber 55 to the lower film-forming chamber 51 by the first central robot CR1.

[0112] According to this variation, the first firing step is to fire the substrate at any temperature from 100°C to 150°C. If the first firing step is set to low-temperature firing, a power-saving substrate processing method can be provided. In particular, when the solvent of the first coating liquid is PGME or PGMEA, the substrate W is preferably fired at a temperature of 200°C or higher in the first firing step.

[0113] In addition, the drying of the first layer 101 can also be carried out by other drying methods such as vacuum drying.

[0114] <Modification 4> According to the above configuration, the solvent contained in the second layer 102 is removed by natural drying or rotary drying, but the present invention is not limited to this configuration. That is, it can be configured to have a second firing step to remove the solvent contained in the second layer 102 after step S14 and before step S16. According to this configuration, since the second layer 102 can be dried reliably, the SOG layer 106 is easily formed. The second firing step is also implemented by the heat treatment chamber 55 shown in FIG1. ​​The transfer of the substrate W between the lower film-forming chamber 51 and the heat treatment chamber 55 is implemented by the first central robot CR1.

[0115] According to this variation, the second firing step is to fire the substrate at any temperature from 100°C to 150°C. If the second firing step is set to low-temperature firing, a power-saving substrate processing method can be provided. In particular, when the solvent of the second coating liquid is PGME or PGMEA, the substrate W is preferably fired at a temperature of 200°C or higher in the second firing step.

[0116] In addition, the drying of the second layer 102 can also be carried out by other drying methods such as vacuum drying.

[0117] <Modified Example 5> In addition, the present invention can also be applied to forming a laminated structure other than the structure shown in FIG9 by providing an anti-reflection film between the SOG layer 106 and the photoresist layer 107.

[0118] <Modified Example 6> In the above configuration, the first layer 101 and the second layer 102 are formed in the same lower film-forming chamber 51, but the present invention is not limited to this configuration. The first layer 101 and the second layer 102 may also be formed by different chambers.

[0119] <Modification 7> The lower film-forming chamber 51 described above forms the first layer 101 by spin coating, but the present invention is not limited to this configuration. The first layer 101 can also be formed by capillary coating or slit coating. The same applies to the second layer 102. [Simplified Explanation of the Diagram]

[0027] Figure 1 is a top view illustrating the overall configuration of the substrate processing apparatus of the embodiment. Figure 2 is a cross-sectional view illustrating the configuration of the light irradiation chamber of the embodiment. Figure 3 is a cross-sectional view illustrating the configuration of the light irradiation chamber of the embodiment. Figure 4 is a flowchart illustrating the film formation process of the lower layer of the embodiment. Figure 5 is a cross-sectional view illustrating the film formation process of the lower layer of the embodiment. Figure 6 is a cross-sectional view illustrating the film formation process of the lower layer of the embodiment. Figure 7 is a cross-sectional view illustrating the film formation process of the lower layer of the embodiment. Figure 8 is a cross-sectional view illustrating the film formation process of the lower layer of the embodiment. Figure 9 is a cross-sectional view illustrating the film formation process of the photoresist layer of the embodiment. Figure 10 is a graph showing the appropriate ultraviolet light irradiation amount of the embodiment. Figure 11 is a flowchart illustrating the substrate processing of the embodiment.

Claims

1. A substrate processing method for forming a multilayer structure consisting of an organic layer, a silicon layer, and a photoresist layer on a substrate, characterized by comprising: a first layer forming step of coating a first coating liquid containing an organic material and a first photocrosslinking agent onto the substrate to form a first layer; a second layer forming step of coating a second coating liquid containing a silicon material and a second photocrosslinking agent onto the first layer to form a second layer; a light irradiation step of irradiating the multilayer consisting of the first layer and the second layer with light to harden the first layer through a crosslinking reaction to form the organic layer, and to harden the second layer through a crosslinking reaction to form the silicon layer; and a photoresist layer forming step of forming a photoresist layer on the hardened multilayer.

2. The substrate processing method as described in claim 1, wherein, The first layer in the first layer generation step has: a lower layer that becomes the organic layer in the light irradiation step, and a higher layer that disappears by being dissolved by the second coating liquid.

3. The substrate processing method as described in claim 1, wherein, The solvent of the second coating liquid in the second layer formation step is more difficult to dissolve the organic material than the solvent of the first coating liquid in the first layer formation step.

4. The substrate processing method as described in claim 3, wherein, The second coating liquid in the second layer formation step mentioned above contains additives that promote the dissolution of the silicon material in the solvent.

5. The substrate processing method as described in claim 1, wherein, The light irradiated in the above-mentioned light irradiation step is any type of ultraviolet light with a wavelength of 172 nm to 385 nm.

6. The substrate processing method as described in claim 1, wherein, The aforementioned silicon layer is formed during the aforementioned light irradiation step so that the irradiated light reaches the aforementioned first layer.

7. The substrate processing method as described in claim 1, wherein, It comprises: a first firing step, which removes the solvent contained in the first layer after the first layer formation step and before the second layer formation step; and a second firing step, which removes the solvent contained in the second layer after the second layer formation step and before the light irradiation step.

8. The substrate processing method as described in claim 7, wherein, The first firing step described above involves firing the substrate at any temperature between 100°C and 150°C; the second firing step described above involves firing the substrate at any temperature between 100°C and 150°C.

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