Developing method, developing apparatus, and storage medium

Abstract

The invention provides a developing method, which uses a developing fluid containing at least one of a weak acid gas and a weak acid mist to carry out good substrate developing. The developing method includes a developing step of developing a substrate on which a resist coating film is formed and which has been subjected to an exposure treatment, and in the developing step, a developing fluid which is generated from a developing liquid, contains a weak acid gas and / or a weak acid mist, and in which the concentration of the weak acid is adjusted is supplied into a treatment space. And developing the substrate in the processing space.

Description

Technical Field

[0001] This disclosure relates to developing methods, developing apparatus, and storage media. Background Technology

[0002] Patent Document 1 discloses a substrate processing system comprising a wet processing system, a dry processing system, and a relay transport system. The wet processing system includes a wet processing apparatus that performs any substrate processing by a wet method, from resist film formation on the substrate to resist film development after exposure, and is connected to an exposure apparatus. The dry processing system includes a dry processing apparatus that performs the same type of substrate processing as the wet processing apparatus by a dry method. The relay transport system transports the substrate between the wet processing system and the dry processing system. In the substrate processing system, the wet processing system is configured such that, when viewed from the connection direction between the wet processing system and the exposure apparatus, the exposure apparatus protrudes from a side in the depth direction perpendicular to the connection direction when viewed from above, and the dry processing system is configured to be adjacent to said side in the depth direction of the wet processing system.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2024-17881 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] The technique disclosed herein uses a developing fluid containing at least one of a weak acid gas and a weak acid mist to achieve good substrate development.

[0008] Technical means to solve the problem

[0009] One aspect of this disclosure is a developing method comprising a step of developing a substrate coated with a resist and subjected to exposure treatment, wherein a developing fluid generated from a developing liquid, comprising at least one of a weak acid gas and a weak acid mist, wherein the concentration of the weak acid is adjusted, is supplied to a processing space to develop the substrate within the processing space.

[0010] Invention Effects

[0011] According to this disclosure, it is possible to perform good substrate development using a developing fluid containing at least one of weak acid gas and weak acid mist. Attached Figure Description

[0012] Figure 1 This is a schematic top view showing the general structure of the wafer processing system of the developing apparatus in this embodiment.

[0013] Figure 2 This is a schematic front view showing the general structure of the wafer processing system of the developing apparatus in this embodiment.

[0014] Figure 3 It is a schematic longitudinal cross-sectional view showing the structure of the developing unit.

[0015] Figure 4 It is a schematic cross-sectional view showing the structure of the developing unit.

[0016] Figure 5 It is a schematic longitudinal section representing the general structure of the heat treatment section.

[0017] Figure 6 It is a top view showing the general configuration of the heaters in the hot plate.

[0018] Figure 7 It is a schematic top view showing the structure of the upper surface side of the hot plate.

[0019] Figure 8 It is a schematic, partially enlarged cross-sectional view showing the general structure of the periphery of the hot plate.

[0020] Figure 9 This is a diagram illustrating the structure of the fluid supply mechanism for developing.

[0021] Figure 10 This is a diagram illustrating an example of the configuration of supply organizations.

[0022] Figure 11 This is a diagram illustrating an example of the configuration of supply organizations.

[0023] Figure 12 This is a flowchart illustrating the main steps of the processing flow in Example 1.

[0024] Figure 13 This is a flowchart of the main steps in Example 2, which represents the processing flow performed by the wafer processing system.

[0025] Figure 14 This is a flowchart of the main steps in Example 3, representing the processing flow performed by the wafer processing system.

[0026] Figure 15 This is a flowchart of the main steps in Example 4, which represents the processing flow performed by the wafer processing system.

[0027] Figure 16 This is a graph representing the evaluation results of a variation of Example 4, which is a processing flow executed by the wafer processing system.

[0028] Figure 17This is a diagram illustrating another example 1 of a fluid supply mechanism for developing.

[0029] Figure 18 This is another example 2 used to illustrate the supply mechanism for the developing fluid.

[0030] Figure 19 This is another example 2 used to illustrate the supply mechanism for the developing fluid.

[0031] Figure 20 This is a diagram illustrating another example of a method for discharging cryogenic gas from the outlet of a hot plate.

[0032] Figure 21 This is a diagram illustrating another example of a method for reducing the developing fluid during development.

[0033] Figure 22 This is a diagram used to illustrate an example of gas being expelled from the outlet of a hot plate.

[0034] Figure 23 This is a flowchart illustrating the main steps of a process flow that shows the cleaning fluid being discharged from the outlet of a hot plate.

[0035] Figure 24 This is a longitudinal cross-sectional view used to illustrate other examples of vaporizers. Detailed Implementation

[0036] Hereinafter, the wafer processing system and the developing fluid supply device of the developing apparatus according to this embodiment will be described with reference to the accompanying drawings. Furthermore, in this specification and the accompanying drawings, elements having substantially the same functional structure are labeled with the same reference numerals, thereby omitting repeated descriptions.

[0037] <Wafer Processing System>

[0038] First, the structure of the wafer processing system of the developing apparatus in this embodiment will be described. Figure 1 , Figure 2 These are schematic top views and front views showing the general structure of the wafer processing system 1. In this embodiment, the wafer processing system 1 is described as a photolithography system that performs resist film formation and development processes on a semiconductor wafer (hereinafter referred to as "wafer") W, which serves as a substrate.

[0039] like Figure 1As shown, the wafer processing system 1 includes a cassette station 2 and a processing station 3. A cassette C containing multiple wafers W is fed into and out of the cassette station 2. The processing station 3 has multiple processing devices that perform prescribed processing on the wafers W. Furthermore, the wafer processing system 1 has a structure that integrally connects the cassette station 2 and an interface station 4. The interface station 4 performs wafer W exchange between the processing station 3 and an exposure device (not shown) adjacent to the processing station 3 on the opposite side. Additionally, as... Figure 1 As shown, processing station 3 has two units between box station 2 and interface station 4, but it can also have one unit or more than three units.

[0040] The cassette station 2 is equipped with a cassette loading stage 21, a wafer transport device 22, and a wafer transport device 23. Multiple cassette loading plates 24 are arranged on the cassette loading stage 21. The cassette station 2 uses either the wafer transport device 22 or the wafer transport device 23 to transport wafers between the cassette C placed on the cassette loading stage 21 and the processing station 3. Therefore, the wafer transport device 22 and the wafer transport device 23 may, as needed, have drive mechanisms with movement paths in various directions, such as horizontal (X and Y directions), vertical (Z direction), and around the vertical axis (θ direction), or drive mechanisms with movement paths in all directions.

[0041] At least one of the wafer transport device 22 and wafer transport device 23 is capable of transferring wafers W to the cassette C, and also capable of transferring wafers to the processing station 3. Furthermore, transferring wafers W to the processing station 3 refers, for example, to transferring wafers to a third block G3, wherein the third block G3 has transfer devices accessible to the wafer transport device 33 within the processing station 3 (described later). The third block G3 may have multiple transfer devices (not shown) arranged vertically.

[0042] In addition, an inspection device (not shown) for inspecting the wafer W can be provided at a location accessible to either the wafer transport device 22 or the wafer transport device 23.

[0043] Processing station 3 has multiple blocks, such as the first, second, and fourth blocks G1, G2, and G4. Additionally, as... Figure 2 As shown, multiple layers 31, each containing first and second blocks G1 and G2, are stacked vertically. For example, on the front side of processing station 3 ( Figure 1 The first block G1 is set on the negative X-direction side, on the back side of processing station 3. Figure 1 A second block G2 is located on the positive X-direction side of processing station 3. On the interface station 4 side of processing station 3 ( Figure 1A fourth block G4 is provided on the part that connects to other adjacent processing stations 3 (on the positive Y-direction side). The fourth block G4 may have multiple connection devices arranged in the vertical direction. In addition, the aforementioned third block G3 may also be provided within the processing station 3.

[0044] The first block G1 is equipped with multiple processing devices, such as a patterning film forming apparatus and a developing apparatus (not shown). The patterning film forming apparatus may include, for example, an anti-reflective film forming apparatus in addition to a resist film forming apparatus.

[0045] For example, multiple processing devices are arranged horizontally in the first block G1. Furthermore, the number, configuration, and type of these processing devices in the first block G1 can be arbitrarily selected.

[0046] In these patterning film forming apparatuses and developing apparatuses, for example, a prescribed processing solution or a prescribed gas is supplied to the wafer W. Thus, in the patterning film forming apparatus, resist films, anti-reflective films, etc., are formed. The resist film is used as a mask when forming the pattern of the underlying film, and the anti-reflective film is used for efficient light irradiation processing, such as exposure processing. On the other hand, in the developing apparatus, a portion of the exposed resist film is removed to form the uneven shape of the aforementioned mask.

[0047] For example, in the second block G2, heat treatment devices (not shown) for heating and cooling wafer W are arranged in both the vertical and horizontal directions. Additionally, in the second block G2, although not shown, hydrophobic treatment devices for improving the adhesion of the resist to the wafer W and peripheral exposure devices for exposing the outer periphery of the wafer W are arranged in both the vertical (Z-direction) and horizontal directions. The number and arrangement of these heat treatment devices, hydrophobic treatment devices, and peripheral exposure devices can be arbitrarily selected.

[0048] like Figure 1 As shown, a wafer transport region 32 is formed in the area between the first block G1 and the second block G2 when viewed from above. A wafer transport device 33, for example, is disposed in the wafer transport region 32.

[0049] The wafer transport device 33 has, for example, a transport arm capable of moving in the Y direction, front-back direction, θ direction, and Z direction. The wafer transport device 33 moves within the wafer transport area 32 and is capable of transporting the wafer W to designated locations within the surrounding first block G1, second block G2, third block G3, and fourth block G4. Figure 1In the case of multiple processing stations 3, the wafer transport device 33 installed in the processing station 3 located on the side of the interface station 4 can transport the wafer W to the first, second, and fourth blocks G1, G2, and G4, as well as to the specified device in the fifth block G5 described later.

[0050] Wafer transport device 33, for example, Figure 2 As shown, multiple units are arranged vertically. One wafer transport device 33 can transport a wafer W to a specified device located at the height of the upper layer 31 among multiple stacked layers 31. For specified devices located at the height of the lower layers 31, wafer W can be transported by other wafer transport devices 33. Multiple wafer transport areas 32 are arranged in such a way that wafer W can be transported. Furthermore, the number of wafer transport devices 33 and the number of layers 31 corresponding to one wafer transport device 33 can be arbitrarily selected; for example, a wafer transport device 33 can be provided for each layer 31.

[0051] Additionally, a shuttle transport device (not shown) may be present in wafer transport area 32 or in the first block G1 or the second block G2. The shuttle transport device linearly transports the wafer W between the space adjacent to one side of the processing station 3 and other adjacent spaces on the opposite side.

[0052] Interface station 4 is equipped with a fifth block G5 containing multiple transfer devices, a wafer transport device 41, and a wafer transport device 42. Between the fifth block G5, where wafer W is transferred via wafer transport device 33, and the exposure device, interface station 4 uses either wafer transport device 41 or wafer transport device 42 to transport wafer W. Therefore, wafer transport devices 41 and 42 may, as needed, have drive mechanisms with movement paths in various directions, such as horizontal (X-direction, Y-direction), vertical (Z-direction), and around the vertical axis (θ-direction), or drive mechanisms with movement paths in all directions. Wafer W can be supported by at least one of wafer transport devices 41 and 42, and transported between the transfer devices and the exposure device within the fifth block G5.

[0053] Within the interface station 4, at a location accessible to either the wafer transport device 41 or the wafer transport device 42, a cleaning device for cleaning the surface of the wafer W and the aforementioned peripheral exposure device can be installed.

[0054] The inspection device, as described above, can be installed in the box station 2, but it can also be installed in either of the conveyor arms (composed of) within the processing station 3 and the interface station 4. Figure 1 or Figure 2 The wafer transport devices 33, 41, and 42 in the middle have the position that can be approached.

[0055] The wafer processing system 1 described above includes at least one control unit 100. The control unit 100 is capable of processing computer-executable commands to cause the wafer processing system 1 to perform the various processes described herein. The control unit 100 may be configured to control various elements of the wafer processing system 1 to perform the various processes described herein. In one embodiment, part or all of the control unit 100 may be included in the wafer processing system 1. The control unit 100 may also include a processing unit, a storage unit, and a communication interface. The control unit 100 is implemented, for example, by a computer. The processing unit may be configured to read a program from the storage unit that provides logic or routines capable of performing various control actions, and perform various control actions by executing the read program. The program may be stored in the storage unit in advance or retrieved via a medium when needed. The retrieved program is stored in the storage unit and read and executed by the processing unit from the storage unit. The medium may be various computer-readable storage media H, or a communication line connected to the communication interface. The storage medium may be temporary or non-temporary. The processing unit can be a CPU (Central Processing Unit) or one or more circuits. The storage unit can include RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof. The communication interface can communicate with the wafer processing system 1 via a communication line such as a LAN (Local Area Network).

[0056] Furthermore, the wafer processing system in this disclosure is not limited to the structure described above. For example, in the above embodiment, the wafer processing system is directly connected to the exposure apparatus, and the wafer W is transferred between the interface station 4 and the exposure apparatus. However, the wafer processing system may not be directly connected to the exposure apparatus. In this case, for example, after the wafer W is transported from the cassette station 2 to the processing station 3 for necessary processing, it is transported back to the cassette station 2 in order to be sent outside the system.

[0057] Furthermore, any devices listed as processing apparatus that are not required may be omitted from the wafer processing system, or the processing within those devices may be omitted.

[0058] <Types of corrosion resists>

[0059] In the wafer processing system 1 disclosed herein, the resist film formed on the wafer W by the resist film forming apparatus is a resist film containing metal resist, i.e., a metal resist film.

[0060] In addition, metal-containing resists are substances that contain metal as a component of resists, and do not mean resists that only contain metal as an impurity.

[0061] Metal-containing resists are materials that form resist films on the surface of a substrate and contain metals with ligands.

[0062] The metals that constitute the resist can be selected from any one or a combination thereof, such as tin (Sn), tungsten (W), hafnium (Hf), zirconium (Zr), indium (In), tellurium (Te), antimony (Sb), nickel (Ni), cobalt (Co), titanium (Ti), tungsten (W), tantalum (Ta), molybdenum (Mo), bismuth (Bi), iodine (I), and germanium (Ge), but are not limited to the metals described herein.

[0063] As an example of a reaction involving metal resists, for instance, after the bonds between the metal and ligands break (i.e., ligand detachment), a condensation reaction occurs, resulting in an oxide state where the metal bonds with each other via oxygen atoms. This oxide state of the metal is a more stable compound than its original state. The ligand detachment is primarily driven by exposure, and the condensation reaction is primarily driven by heating after exposure. As a result, the oxide state of the metal is present in the resist film.

[0064] <Developing Unit 200>

[0065] Next, the developing unit 200, which is the developing section of this disclosure, will be described. Figure 3 and Figure 4 These are schematic longitudinal and cross-sectional views, respectively, showing the structure of the developing unit 200. Figure 5 This is a schematic longitudinal section showing the structure of the heat treatment section 310, which will be described later. Figure 6 This is a top view showing the general configuration of the heaters in the hot plate 360, which will be described later.

[0066] Figure 7 This is a schematic top view showing the structure of the upper surface side of the hot plate 360. Figure 8 This is a schematic, partially enlarged cross-sectional view showing the general structure of the periphery of the hot plate 360.

[0067] Figure 3 and Figure 4The developing unit 200 develops a wafer W that has a resist coating and has undergone exposure treatment using a developing fluid containing a weak acid gas. Specifically, the developing unit 200 develops a wafer W that has a metal resist coating and has undergone exposure treatment and post-exposure heat treatment (PEB treatment) using a developing fluid containing a weak acid gas. The exposure treatment here is a process performed by an exposure apparatus that uses exposure light to transfer the pattern of the mask.

[0068] The developing unit 200 is, for example, located in the same block as the heat treatment apparatus that performs heat treatment such as heating of the wafer W in the wafer processing system 1, namely the second block G2.

[0069] The developing unit 200 has a processing container 300 capable of sealing its interior. A wafer W feed outlet (not shown) is formed on the side of the processing container 300 on the wafer transport area side (the area where the wafer transport device 41 and the wafer transport device 42 are provided), and an opening and closing gate (not shown) is provided at the feed outlet.

[0070] Inside the processing container 300, there is a heat treatment unit 310 that performs heat treatment on the wafer W, and a temperature regulation unit 311 that regulates the temperature of the wafer W. The heat treatment unit 310 and the temperature regulation unit 311 are arranged in the Y direction, and the temperature regulation unit 311 is provided on the feed-outlet side of the heat treatment unit 310.

[0071] like Figure 5 As shown, the heat treatment unit 310 has a chamber 320, which forms a processing space K1 for receiving the wafer W and has an outlet 331 for discharging developing fluid in the processing space K1. The chamber 320 has an upper chamber 321 located on the upper side and which can be raised and lowered, and a lower chamber 322 located on the lower side and which can be integrated with the upper chamber 321 to seal the interior.

[0072] The upper chamber 321 is configured to be raised and lowered via a lifting mechanism (not shown). The lifting mechanism has a drive source (not shown) such as an electric motor that generates the driving force for raising and lowering the upper chamber 321. The lifting mechanism is controlled by a control unit 100.

[0073] The upper chamber 321 is, for example, formed into a generally cylindrical shape with an opening on its lower surface. Inside the upper chamber 321, opposite the hot plate 360 ​​described later, a spray head 330 is provided as a gas discharge section. The spray head 330 is configured to rise and fall synchronously with the upper chamber 321.

[0074] On the lower surface of the spray head 330, a plurality of outlets 331 are formed for discharging a developing fluid containing a weak acid gas into the processing space K1. Each outlet 331 discharges the developing fluid containing the weak acid gas from above the hot plate 360 ​​toward the hot plate 360. The weak acid gas is, for example, a gas of a carboxylic acid, which is a weak acid. Alternatively, the gas of a carboxylic acid, which is a weak acid, can be, for example, acetic acid vapor. In this disclosure, "weak acid" refers to an acid with an acid dissociation constant (pka) of 4 or more (e.g., about 5). In addition, the developing fluid containing the weak acid gas contains, for example, a vapor of a mixture of a carboxylic acid, which is a weak acid, and an organic solvent, and a carrier gas. In addition, the developing fluid containing the weak acid gas may contain a vapor from a carboxylic acid monomer, which is a weak acid, and a carrier gas. Specifically, the carboxylic acid, which is a weak acid, is, for example, acetic acid. The organic solvent is, for example, propylene glycol methyl ether acetate (PGMEA). The carrier gas is, for example, an inert gas such as nitrogen or argon (Ar).

[0075] Multiple discharge ports 331 are evenly arranged on the lower surface of the spray head 330, excluding the exhaust port 341 described later. In the spray head 330, a supply mechanism 500 for the developing fluid containing a weak acid gas is connected as a developing fluid supply device.

[0076] A central exhaust path 340 is formed in the spray head 330, extending upward from the exhaust port 341 formed in the center of the lower surface of the spray head 330. An exhaust device 343, such as a vacuum pump, is connected to the central exhaust path 340 via an exhaust pipe 342. Furthermore, an exhaust device assembly 344, including a valve for adjusting the exhaust volume, is provided in the exhaust pipe 342. The exhaust device 343 and the exhaust device assembly 344 are controlled by the control unit 100. In this embodiment, the central exhaust path 340, exhaust pipe 342, exhaust device 343, and exhaust device assembly 344 constitute the central exhaust section of this disclosure, which exhausts air from a position near the top center of the wafer W on the hot plate 360 ​​into the processing space K1.

[0077] An outer peripheral exhaust path 350 is formed inside the upper chamber 321, extending downward from an exhaust port 351 that surrounds the outer periphery of the spray head. An exhaust device 353, such as a vacuum pump, is connected to the outer peripheral exhaust path 350 via an exhaust pipe 352. Furthermore, an exhaust device assembly 354, including a valve for adjusting the exhaust volume, is provided on the exhaust pipe 352. In this embodiment, the outer peripheral exhaust path 350, exhaust pipe 352, exhaust device 353, and exhaust device assembly 354 constitute the outer peripheral exhaust section of this disclosure, which exhausts air from the peripheral portion of the wafer W on the hot plate 360, which, when viewed from above, is closer to the central exhaust section than described above, into the processing space K1.

[0078] The lower chamber 322 has a generally cylindrical shape with an opening on its upper surface. A hot plate 360 ​​and an annular retaining member 361 are provided at the opening on the upper surface of the lower chamber 322 to house the hot plate 360 ​​and hold its periphery. The hot plate 360 ​​is a generally circular plate with a thickness, capable of supporting the wafer W within the processing space K1 and heating the wafer W located above the hot plate 360.

[0079] The hot plate 360 ​​has a main body 360a formed in the shape of a plate (specifically a circular plate) and incorporating a heater 360b. The heater 360b is, for example, a resistance heater. The temperature of the hot plate 360 ​​(specifically, the temperature of the main body 360a) is regulated, for example, by controlling the heater 360b through the control unit 100, thereby heating the wafer W, which is located above the hot plate 360 ​​and supported thereon, to a predetermined temperature.

[0080] The hot plate 360 ​​can be configured to heat the wafer W in different ways, radially and circumferentially, using the heating amount of the wafer W. Specifically, the hot plate 360 ​​can be configured as follows: Figure 6 It is constructed as shown.

[0081] Figure 6 The heat plate 360 ​​(specifically, the main body 360a) is divided into multiple, for example, five regions R1 to R5. Region R1 is a circular region located in the center of the heat plate 360 ​​when viewed from above. Regions R2 to R5 are arc-shaped regions that divide the annular region located outside region R1 into four equal parts when viewed from above. If region R1 is designated as the first region and the annular regions R2 to R3 are designated as the second region, then the first region and the second region are respectively arranged concentrically with the heat plate 360.

[0082] Heaters 360b are built into each of the regions R1 to R5 of the heating plate 360. Each heater 360b can individually heat each region R1 to R5. Additionally, each region R1 to R5 can be equipped with a temperature sensor (not shown). The temperature sensor measures the temperature of each region R1 to R5. The control unit 100 adjusts the temperature measured by each temperature sensor to a set temperature for each region R1 to R5 based on the heat output of the heater 360b in each region R1 to R5.

[0083] Furthermore, the number and configuration of the areas divided in the hot plate 360 ​​can be arbitrarily selected.

[0084] In addition, such as Figure 7 and Figure 8 As shown, the main body 360a of the hot plate 360 ​​is provided with a plurality of protrusions 360c that are provided in a manner that protrude from its upper surface and support the wafer W. The plurality of protrusions 360c are provided, for example, at the following positions.

[0085] Along the radial direction of the upper surface of the main body 360a (i.e., the radial direction of the wafer W supported by the hot plate 360), the upper surface is divided into multiple regions, and a protrusion 360c is provided in each region. Specifically, a plurality (more than three) portions of the upper surface in each region, at different circumferential positions, are provided with protrusions 360c.

[0086] Furthermore, a discharge port 360d is formed in the main body 360a to discharge an inactive gas (such as nitrogen) as a specified gas. The discharge port 360d discharges the inactive gas toward the back side of the wafer W, which is located above the hot plate 360 ​​within the processing space K1 and is supported by the hot plate 360, specifically toward the peripheral area of ​​the back side of the wafer W. As a result, for example, it is possible to suppress the adhesion of substances generated during development, such as sublimation from the metal resist film (hereinafter referred to as development products), to the peripheral area of ​​the back side of the wafer W.

[0087] Specifically, the discharge port 360d is located at the bottom of the groove 360e, which is annular in plan view (more specifically, circular in plan view) formed on the upper surface of the main body 360a.

[0088] A supply mechanism 363 for inactive gas is connected to the outlet 360d via a supply path 362. Although not shown in the figure, the supply mechanism 363 includes, for example, a supply device assembly comprising a supply source for the inactive gas, an on / off valve for controlling the flow of the inactive gas, and a flow regulating valve. This supply device assembly is controlled by a control unit 100. As a heating unit that heats the gas discharged from the outlet 360d outside the chamber 320 and outside the hot plate 360, a heat exchanger 364 is provided in the supply path 362. The heat exchanger 364 is controlled by the control unit 100. In addition, the heat exchanger 364 is provided, for example, inside a processing container 300 that separates the chamber 320 from the outside (such as the vaporizer 501 described later), specifically, as... Figure 3 As shown, the temperature regulating plate 380 (described later) is positioned below the initial state within the processing container 300. Gas discharged from the outlet 360d is heated by the heat exchanger 364 to a temperature at least higher than that of the wafer W.

[0089] Alternatively, instead of connecting the supply mechanism 363 to the outlet 360d, the supply mechanism for the inert gas can be connected to the supply mechanism 500. That is, the inert gas discharged from the outlet 360d can be the same inert gas used in the supply mechanism 500.

[0090] The more outlets 360d there are, the more uniformly the inactive gas can be supplied to the circumference of the hot plate 360 ​​(i.e., the circumference of the wafer W supported by the hot plate 360); the fewer the outlets 360d, the less influence they have on the temperature distribution of the hot plate 360. Therefore, to suppress the influence of the outlets 360d on the temperature distribution of the hot plate 360, such as... Figure 7 As shown, two or more discharge outlets 360d can be intermittently arranged along the groove 360e, and as... Figure 8 As shown, the width of the groove 360e is larger than the diameter (or width) of the outlet 360d so that the specified gas can be uniformly diffused in the circumferential direction.

[0091] The groove 360e is, for example, provided in a region opposite to the peripheral back side of the wafer W when supported by the hot plate 360. In this example, the distance from the wafer W supported by the hot plate 360 ​​(specifically, supported by the protrusion 360c) to the main body 360a is greater at the outer side of the groove 360e than at the inner side. Therefore, the inactive gas emitted from the outlet 360d formed at the bottom of the groove 360e can be suppressed from reaching a position further inward than the groove 360e, and the inactive gas can be efficiently directed to the peripheral edge of the wafer W supported by the hot plate 360. Therefore, by utilizing the inactive gas emitted from the outlet 360d formed at the bottom of the groove 360e, the adhesion of products to the peripheral back side of the wafer W during development can be effectively suppressed.

[0092] In addition, the main body 360a of the hot plate 360 ​​may be provided with a plurality of adsorption holes (not shown) for adsorbing the wafer W onto the hot plate 360.

[0093] like Figure 3 As shown, inside the lower chamber 322 and below the hot plate 360, there are, for example, three lifting pins 370 serving as lifting components, used to support the wafer W from below and move it up and down. The lifting pins 370 can move up and down via a lifting drive unit 371 with a drive source such as an electric motor. Near the center of the main body 360a of the hot plate 360, for example, three through holes 372 extending through the main body 360a in the thickness direction are formed. Moreover, the lifting pins 370 can protrude from the upper surface of the main body 360a of the hot plate 360 ​​by inserting through the through holes 372.

[0094] like Figure 3 and Figure 4As shown, the temperature regulating unit 311 includes a temperature regulating plate 380. The temperature regulating plate 380 is a generally square flat plate, with the end face on the hot plate 360 ​​side curved into an arc shape. Two slits 381 are formed in the temperature regulating plate 380 along the Y direction. The slits 381 extend from the end face on the hot plate 360 ​​side of the temperature regulating plate 380 to near the center of the temperature regulating plate 380. Through these slits 381, interference between the temperature regulating plate 380 and the lifting pin 370 and the lifting pin 390 described later can be prevented. In addition, temperature regulating components (not shown), such as cooling water and Peltier elements, are built into the temperature regulating plate 380. The temperature of the temperature regulating plate 380 is controlled, for example, by the control unit 100, to adjust the wafer W placed on the temperature regulating plate 380 to a predetermined temperature.

[0095] A temperature regulating plate 380 is supported on a support arm 382. A drive unit 383 with a drive source such as an electric motor is mounted on the support arm 382. The drive unit 383 is mounted on a track 384 extending in the Y direction. The track 384 extends from the temperature regulating unit 311 to the heat treatment unit 310. Through the drive unit 383, the temperature regulating plate 380 can move along the track 384 between an initial position in the temperature regulating unit 311 and a junction position in the heat treatment unit 310.

[0096] Furthermore, at the aforementioned initial position, the wafer W is transferred between the transport arm of the wafer transport device 41 or the wafer transport device 42 and the temperature regulating plate 380 via the lifting pin 390 (described later). Additionally, at the aforementioned transfer position, the wafer W is transferred between the hot plate 360 ​​and the temperature regulating plate 380 via the lifting pin 370 (described later).

[0097] Below the temperature regulating plate 380, there are, for example, three lifting pins 390 for supporting the wafer W from below and raising and lowering it. The lifting pins 390 can move up and down via a lifting drive unit 391 with a drive source such as an electric motor. Moreover, the lifting pins 390 can protrude from the upper surface of the temperature regulating plate 380 through the slot 381.

[0098] <Supply-Sector 500>

[0099] Next, the fluid supply mechanism 500 for developing will be described. Figure 9 This is a diagram illustrating the structure of the fluid supply mechanism 500 for developing.

[0100] Supply institutions 500, for example Figure 9As shown, a vaporizer 501 is included as a developing fluid generating unit that generates developing fluid from developing liquid. The vaporizer 501 vaporizes a mixture of acid and organic solvent, which is the developing liquid, to generate developing fluid. The vaporizer 501 is connected to one end of a supply path 502. The other end of the supply path 502 is connected to the developing unit 200, specifically to the spray head 330 of the developing unit 200. The supply path 502 is made of a fluoropolymer resin that is resistant to acid corrosion. Furthermore, a heater 503 is provided in the supply path 502 as a heating unit for heating the developing fluid supplied to the developing unit 200 via the supply path 502. The heater 503 is formed, for example, in a strip shape, i.e., a strip heater, and is wound around the supply path 502 for use. The heater 503 is controlled by a control unit 100. By controlling the heater 503 through the control unit 100, the temperature of the developing fluid supplied from the supply mechanism 500 is adjusted. Specifically, the temperature is adjusted to a required value. More specifically, the temperature is adjusted so that the temperature at which the wafer W is reached in the processing space K1 is a required value (e.g., the same as the temperature of the wafer W).

[0101] The heater 503 is provided at least downstream of the supply path 502. Upstream of the portion of the supply path 502 where the heater 503 is located, an on / off valve 504 is provided to control the flow of developing gas within the supply path 502. The on / off valve 504 is controlled by the control unit 100.

[0102] The vaporizer 501 is connected to a supply source 511 for an inert gas, which serves as the carrier gas, via a gas supply path 512. A supply equipment assembly 513 is provided in the gas supply path 512, including an on / off valve for controlling the flow of the inert gas within the gas supply path 512 and a gas flow regulating valve 513a for regulating the flow rate of the inert gas. The supply equipment assembly 513 is controlled by the control unit 100.

[0103] Additionally, in the vaporizer 501, a tank 521 for storing a mixed solution of acid and organic solvent is connected via a liquid supply path 522. A supply equipment assembly 523 is provided in the liquid supply path 522, including an on / off valve for controlling the flow of the mixed solution through the liquid supply path 522 and a liquid flow regulating valve 523a for regulating the flow rate of the mixed solution. The supply equipment assembly 523 is controlled by the control unit 100. Furthermore, the supply of the mixed solution of acid and organic solvent is not limited to the tank 521; for example, it can be configured such that a supply pipe for the mixed solution from equipment within a factory equipped with the developing apparatus 30 is connected to the liquid supply path 522.

[0104] Furthermore, a branch path 505 is connected to the supply path 502. Specifically, one end of the branch path 505 is connected between the vaporizer 501 and the on / off valve 504 in the supply path 502. The other end of the branch path 505 is connected to the drain tank 530, which also functions as a condenser to liquefy the mixed solution of acid and organic solvent contained in the developing fluid. An on / off valve 506 is provided in the branch path 505 to control the flow of the developing fluid within the branch path 505. The on / off valve 506 is controlled by the control unit 100.

[0105] In the supply mechanism 500, for example, the vaporizer 501 continuously generates developing fluid, and the generated developing gas can be supplied to the developing unit 200, otherwise flowing toward the branch path 505. In this way, by continuously generating developing fluid by the vaporizer 501, the concentration of developing fluid can be maintained at a constant level, that is, the developing performance using developing fluid can be stabilized.

[0106] Furthermore, in the supply mechanism 500, the vapor of the mixture of acid and organic solvent contained in the developing fluid flowing toward the branch path 505 is condensed and reliquefied in the drain tank 530, and accumulated therein. The liquid accumulated in the drain tank 530 can be returned to the tank 521 or the vaporizer 501 as the aforementioned mixture that constitutes the source of the developing fluid. That is, the aforementioned mixture can be recycled.

[0107] In addition, the vaporizer 501 has a flow path 541 for the flow of inactive gas, a flow path 542 for the flow of the mixed solution, and a flow path 543 for the flow of the mixed fluid obtained by mixing the inactive gas and the mixed solution, and for heating the mixed fluid to vaporize the mixed solution.

[0108] Furthermore, in vaporizer 501, the inner wall surface of the flow path for supplying acid (liquid) or acid vapor is formed of a nickel-chromium alloy, silicon, or a silicon compound that is resistant to acid corrosion. Specifically, in vaporizer 501, for example, the components forming flow paths 541, 542, and 543 are made of nickel-chromium alloy, silicon, or a silicon compound.

[0109] Additionally, the supply mechanism 500 includes a concentration sensor 550 for measuring the concentration of the weak acid in the developing fluid. The concentration sensor 550 is, for example, located between the vaporizer 501 and the on / off valve 504 in the supply path 502. The measurement result from the concentration sensor 550 is sent to the control unit 100. Through control by the control unit 100 based on the measurement result from the concentration sensor 550, the concentration of the weak acid in the developing fluid supplied from the supply mechanism 500 is adjusted; specifically, the concentration is adjusted to a desired value. In the supply mechanism 500, the concentration of the weak acid in the developing fluid can be adjusted, for example, by the heating temperature of the mixed solution in the vaporizer 501 (specifically, the heating temperature of the mixed fluid in the flow path 543 of the vaporizer 501), the supply flow rate of the mixed solution to the vaporizer 501, or the supply flow rate of the inactive gas as a carrier gas to the vaporizer 501.

[0110] At least a portion of the supply mechanism 500 is disposed adjacent to, for example, the developing unit 200 to which the developing fluid is supplied. Specifically, a portion of the supply mechanism 500 including the vaporizer 501 is disposed adjacent to the developing unit 200 to which the developing fluid is supplied.

[0111] The developing apparatus of this embodiment includes at least a vaporizer 501 of the supply mechanism 500 and the developing unit 200 described above.

[0112] <Configuration of Supply Chain 500>

[0113] Figure 10 and Figure 11 These are diagrams illustrating an example of the configuration of the supply mechanism 500, showing the back side (positive side in the X direction) of the second block G2 in the wafer processing system 1.

[0114] A portion of the supply mechanism 500, including the vaporizer 501 and the concentration sensor 550, can be modularized. This block BL of the supply mechanism 500, including the vaporizer 501 and the concentration sensor 550, can be configured to be positioned at the same height as the developing unit 200, opposite to the destination of the developing fluid supply. Alternatively, the block BL can be configured to be positioned adjacent to the developing unit 200, the destination of the developing fluid supply.

[0115] In the second block G2 of the wafer processing system 1, for example, as Figure 10As shown, two stacked developing units 200 and an electrical assembly unit 201 stacked on top of and shared by the two developing units 200 are designated as a single combined unit Gr. Multiple such combined units Gr are then arranged in both the horizontal and vertical directions. In this case, for example, the blocks BL corresponding to the two developing units 200 contained in the single combined unit Gr can be merged into a single shared block BLm, and arranged adjacent to the back side (the face on the positive side in the X direction) of the combined unit Gr. This allows for good controllability and responsiveness of the concentration and flow rate of the developing fluid supplied to the developing unit 200. Furthermore, the shared block BLm is preferably configured such that the vaporizer 501 and concentration sensor 550 contained in the shared block BLm are not opposite the electrical assembly unit 201, but rather opposite the developing unit 200 to which the fluid is supplied.

[0116] Additionally, in the second block G2 of the wafer processing system 1, for example, as Figure 11 As shown, sometimes a single developing unit 200 and an electrical assembly unit 201 arranged horizontally and corresponding to the developing unit 200 are considered as a single combined unit Gr, with multiple such combined units Gr arranged in both the horizontal and vertical directions. In this case, the block BL corresponding to the developing unit 200 contained in the combined unit Gr can also be arranged adjacent to the back side (the face on the positive side in the X direction) of the combined unit Gr. This allows for good controllability and responsiveness of the concentration and flow rate of the developing fluid supplied to the developing unit 200. Furthermore, the block BL is preferably configured such that the vaporizer 501 and the concentration sensor 550 contained in the block BL are not opposite to the electrical assembly unit 201, but rather opposite to the developing unit 200 at the supply destination.

[0117] Furthermore, the blocks BL or common blocks BLm of the supply mechanism 500 can be configured to be partially detachable and movable. In this case, by partially removing the blocks BL or common blocks BLm of the supply mechanism 500, the developing unit 200 to which the developing fluid is supplied by the supply mechanism 500 can be maintained. That is, by configuring it as described above, the developing unit 200, on which corresponding blocks BL or common blocks BLm are arranged adjacent to each other on the back side, can be easily maintained.

[0118] <Example 1 of the processing flow>

[0119] Next, an example of the processing flow executed by the wafer processing system 1 will be described. Figure 12 This is a flowchart illustrating the main steps of the processing flow in Example 1.

[0120] (Step S1)

[0121] First, wafer W is fed into wafer processing system 1.

[0122] Specifically, a cassette C containing multiple wafers W is fed into the cassette station 2 of the wafer processing system 1 and placed on the cassette mounting plate 24. Then, each wafer W in the cassette C is sequentially removed using the wafer transport device 22 or the wafer transport device 23 and transported to the handover device of the third block G3.

[0123] (Step S2)

[0124] Next, an anti-reflective coating formation process is performed on wafer W to form an anti-reflective coating on wafer W.

[0125] Specifically, the wafer W, which is being transported to the transfer device in the third block G3, is supported by the wafer transport device 33 and then transported to the anti-reflective film forming device located in the first block G1. An anti-reflective film is formed as a base film containing a metal resist by covering the surface of the wafer W. This step S2 can also be omitted.

[0126] (Step S3)

[0127] Next, a resist coating process is performed on wafer W to form a resist film on wafer W.

[0128] Specifically, the wafer W is supported by the wafer transport device 33 and transported to the resist film forming device located in the first block G1 to form a metal resist film by covering the anti-reflective film as a base film on the wafer W.

[0129] (Step S4)

[0130] Next, PAB processing is performed on wafer W.

[0131] Specifically, wafer W is supported by wafer transport device 33 and transported to the heat treatment unit for PAB processing in the second block G2 for PAB processing. Afterwards, wafer W is transported to the handover device in the fifth block G5. Additionally, in... Figure 1 , 2 In the case of multiple processing stations 3, the wafer W is placed in the transfer device of the fourth block G4 before being transferred to the transfer device of the fifth block G5, and then transferred between multiple wafer transfer devices 33.

[0132] (Step S5)

[0133] Next, the wafer W is exposed.

[0134] Specifically, wafer W, which has been transported to the handover device in the fifth block G5, is transported to the exposure device using wafer transport devices 41 and 42. Wafer W undergoes pattern exposure processing based on EUV (Extreme Ultra-Violet) light. This pattern exposure processing is the exposure process for transferring a mask pattern. The exposed wafer W is then transported by wafer transport devices 41 and 42 to the handover device in the fifth block G5.

[0135] (Step S6)

[0136] Next, the wafer W is subjected to PEB processing in the developing unit 200.

[0137] Specifically, for example, firstly, the wafer W is fed into the processing container 300 of the developing unit 200.

[0138] More specifically, the wafer W, after optical processing and transport to the handover device in the fifth block G5, is fed into the processing container 300 using the wafer transport device 33. Then, the lifting pin 390 rises, transferring the wafer W from the wafer transport device 33 to the lifting pin 390. Next, the lifting pin 390 descends, placing the wafer W on the temperature regulating plate 380 in its initial position. Then, the temperature regulating plate 380 moves to a handover position above the hot plate 360. Afterward, the lifting pin 370 rises, transferring the wafer W to the lifting pin 370. Finally, the temperature regulating plate 380 returns to its initial position.

[0139] After wafer W is placed into processing container 300, PEB processing is performed on wafer W.

[0140] Specifically, for example, the upper chamber 321 descends, sealing the interior of chamber 320 to form processing space K1. Then, the lifting pin 370 descends, moving the wafer W to a PEB processing height separated from the hot plate 360 ​​by a predetermined distance, thus initiating PEB processing. Specifically, the PEB processing height refers to a height at which the temperature of the wafer W becomes a predetermined temperature at which the dehydration condensation energy of the metal resist on the wafer W is advanced; this predetermined temperature is, for example, 140–160°C.

[0141] In the PEB process, at least one of the exhaust from the processing space K1 via the central exhaust path 340 and the exhaust from the processing space K1 via the peripheral exhaust path 350 is performed.

[0142] Alternatively, it can be configured to supply gas for PEB treatment (e.g., oxygen-containing temperature and humidity regulating gas) from the spray head 330, and discharge the gas for PEB treatment from the spray head 330 into the treatment space K1 during PEB treatment.

[0143] For example, the PEB process ends after a specified time has elapsed after wafer W has moved to the PEB processing height.

[0144] In addition, PEB processing can also be carried out through the heat treatment device for PEB processing in the second block G2.

[0145] (Step S7)

[0146] Next, the wafer W is developed using a developing fluid with a weak acid concentration adjusted. Specifically, the wafer W is developed as described above.

[0147] Specifically, for example, firstly, instead of sending the PEB-processed wafer W out of the developing unit 200, the lifting pin 370 supporting the wafer W is lowered within the same developing unit 200. As a result, the wafer W approaches the hot plate 360; more specifically, the wafer W is transferred from the lifting pin 370 to the hot plate 360 ​​(specifically, the protrusion 360c) and supported. Furthermore, the wafer W is adsorbed onto the hot plate 360 ​​via an adsorption hole (not shown).

[0148] Next, a developing fluid from the supply mechanism 500, with its temperature and weak acid concentration adjusted, is supplied to the processing space K1, and the wafer W is developed using this developing fluid.

[0149] Specifically, a developing fluid with a temperature and weak acid concentration adjusted to a required value is discharged from the spray head 330 onto the surface side (front side) of the wafer W. Additionally, at least one of the following is performed: exhaust from the processing space K1 via the central exhaust path 340 and exhaust from the processing space K1 via the peripheral exhaust path 350. Thus, the wafer W, heated by the hot plate 360, is exposed to an acidic atmosphere containing a weak acid gas within the processing space K1. When exposed to the acidic atmosphere, the unexposed portions of the metal resist film on the wafer W react with the weak acid gas, becoming low-molecular-weight. Furthermore, through the heating of the wafer W, the unexposed portions of the metal resist film on the wafer W that have become low-molecular-weight due to the reaction with the weak acid gas sublimate, forming a pattern containing the metal resist. For example, if the weak acid gas is acetic acid gas and the metal resist contains tin as a metal, tin acetate sublimates. The sublimate is discharged outside the processing space K1 through the exhaust from the processing space K1.

[0150] Additionally, in step S7, inactive gas is discharged from the outlet 360d of the hot plate 360 ​​to the back side of the wafer W.

[0151] Therefore, it is possible to prevent the product from spreading to the back side of the wafer W and adhering during development in step S7.

[0152] The steps S7, namely, discharging the developing fluid from the spray head 330, venting the processing space K1, and discharging the inactive gas from the outlet 360d, are carried out at a specified pressure of at least atmospheric pressure within the processing space K1.

[0153] Among them, "atmospheric pressure" is, for example, 670 Torr to 760 Torr.

[0154] (Step S8)

[0155] Next, the wafer W is subjected to weak development using a developing fluid with a weak acid concentration adjusted.

[0156] Specifically, weak development is performed on wafer W using a developing fluid from the supply unit 500, with the temperature and concentration of the weak acid adjusted.

[0157] More specifically, the following operations are performed in step S7.

[0158] • A developing fluid with adjusted temperature and weak acid concentration is ejected from the spray head 330 onto the surface side of the wafer W.

[0159] • At least one of the exhaust gas from the processing space K1 via the central exhaust path 340 and the exhaust gas from the processing space K1 discharged via the peripheral exhaust path 350.

[0160] • Inactive gas is emitted from the outlet 360d of the hot plate 360 ​​towards the back side of the wafer W.

[0161] However, in step S8, at least one of the following operations is performed to make the development of the developing fluid weaker than in step S7.

[0162] • Reduce the amount of developing fluid discharged from the spray head 330 (i.e., reduce the reduction in the amount of developing fluid supplied from the supply mechanism 500 to the spray head 330).

[0163] • Reduce the temperature of the developing fluid ejected from the spray head 330 (i.e., reduce the temperature of the developing fluid supplied from the supply mechanism 500 to the spray head 330).

[0164] • Reduce the concentration of weak acid in the developing fluid from the spray head 330 (i.e., reduce the concentration of the developing fluid supplied from the supply mechanism 500 to the spray head 330).

[0165] • Add a weakly developing agent to the mixture of weak acid and organic solvent supplied to the vaporizer.

[0166] As described above, the concentration of the weak acid in the developing fluid can be adjusted by the heating temperature of the mixed fluid in the flow path 543 of the vaporizer 501 and the supply flow rate of the inactive gas to the vaporizer 501.

[0167] Weakly reproducible substances are those whose acid dissociation constant (pKa) is greater than that of the weak acid contained in the original mixed solution. When the weak acid in the original mixed solution is acetic acid (pKa ≈ 4.76), carboxylic acid-based, alcohol-based, and aminosilane-based substances are examples of weakly reproducible substances, as described below.

[0168] Carboxylic acid system

[0169] Propionic acid (pKa≈4.87)

[0170] Alcohol series

[0171] Methanol (pka≈15.4), 2,2,2-trifluoroethanol (pka≈12.4), nonafluoro-tert-butyl alcohol (pka≈5.4), phenol (pka≈9.95), pentafluorophenol (pka≈5.5)

[0172] • Aminosilane system

[0173] Trimethylsilyl dimethylamine (TMSDMA) (pka≈10.7)

[0174] In addition, the added weakly radioactive substance is preferably a volatile substance that is a gas at room temperature.

[0175] Additionally, in step S8, similar to step S7, inactive gas is discharged from the outlet 360d of the hot plate 360 ​​to the back side of the wafer W.

[0176] Therefore, it is possible to suppress the spread of the product to the back side of the wafer W during development in step S8.

[0177] Furthermore, similar to step S7, the processes of discharging developing fluid from the spray head 330, venting the processing space K1, and discharging inactive gas from the outlet 360d in step S8 are also carried out at a predetermined pressure of at least atmospheric pressure within the processing space K1.

[0178] When a predetermined time has elapsed since the start of step S8, the supply of developing fluid to the processing space K1 is stopped. Specifically, the on / off valve 504 located in the supply path 502 is closed, and step S8 ends.

[0179] The temperature of wafer W during development in steps S7 and S8 is higher than the temperature during PEB processing in step S6, for example, by 180 to 200°C. However, the temperature change of the hot plate 360 ​​is not required during development and PEB processing. This is because, during development in steps S7 and S8, wafer W is closer to the hot plate 360 ​​than during PEB processing, and more specifically, it is supported by the hot plate 360 ​​(specifically, the protrusion 360c). That is, in this example's processing flow, compared to PEB processing, wafer W is brought closer to the hot plate 360 ​​during development, thereby making the processing temperature of wafer W during development higher than that during PEB processing.

[0180] After the supply of developing fluid to the processing space K1 is stopped, the processing space K1 can continue to be vented, and inactive gas can be discharged from the outlet 360d to replace the atmosphere containing weak acid gas in the processing space K1 with an atmosphere of inactive gas. When this replacement is performed, for example, the venting of the processing space K1 and the discharge of inactive gas from the outlet 360d continues for a predetermined period of time after the supply of developing fluid to the processing space K1 is stopped. Alternatively, if the above replacement is not performed, the venting of the processing space K1, etc., also stops at the same time as the supply of developing fluid to the processing space K1 is stopped.

[0181] Then, the wafer W is sent out from the processing container 300.

[0182] Specifically, for example, the wafer W is sent out of the processing container 300 and out of the developing unit 200 in the reverse order of being fed into the processing container 300 in step S6.

[0183] (Step S9)

[0184] After development, the wafer W is subjected to POST processing.

[0185] Specifically, the wafer W is transported to the heat treatment unit 40 for POST processing using the wafer transport device 33, where POST processing is performed. This step S9 can also be omitted.

[0186] (Step S10)

[0187] Then, wafer W is sent out from wafer processing system 1.

[0188] Specifically, the wafer W is transported to the handover device of the third block G3 using the wafer transport device 33, and then transported to the cassette C of the designated cassette carrier plate 24 using the wafer transport device 22 or 23 of the cassette station 2. In this way, a series of photolithography processes are completed.

[0189] <Main Effects of This Implementation Method>

[0190] As described above, Example 1 of the processing flow includes a step (steps S7 and S8) of developing a wafer W coated with a resist (specifically, a metal resist) and subjected to exposure treatment. Furthermore, in the development steps (steps S7 and S8), a developing fluid containing a weak acid gas is supplied to the processing space K1 to develop the wafer W within the processing space K1. Moreover, the concentration of the weak acid in the developing fluid supplied to the processing space K1 is adjusted, specifically, adjusted to a required value. Therefore, according to Example 1 of the processing flow, compared to the case where the concentration of the weak acid in the developing fluid supplied to the processing space K1 is not adjusted, the wafer W can be developed at a required intensity. Therefore, over-development or underdevelopment of the wafer W can be suppressed, and thus development using a developing fluid containing a weak acid gas can be used effectively.

[0191] Furthermore, in Example 1 of the processing flow, in step S8, a later step in the development process (steps S7 and S8), the intensity of development of the wafer W by the developing fluid is reduced compared to step S7. In the development of the wafer W using a developing fluid containing a weak acid gas, the removal of the coating progresses in the thickness direction of the resist coating, i.e., longitudinally, and then laterally, in the direction parallel to the surface of the wafer W. Additionally, in the resist coating, the amount of exposure during the exposure process of the exposure apparatus is reduced on the lower side compared to the surface side. Therefore, in negative development of the resist coating, the removal of the coating on the lower side is easier to advance compared to the surface side. For example, in a coating containing a metal resist, compared to the surface side, the ligands on the lower side are replaced by hydroxyl groups, and subsequent dehydration condensation cannot proceed; therefore, the removal of the coating is easily advanced by negative development. Therefore, if the development is strong during the later stages of development, i.e., when the coating removal is carried out laterally, the resulting resist pattern will appear as a thinner shape at the bottom when viewed in cross-section. Therefore, as described above, in step S8, a later stage of the development process, the intensity of the developing fluid on the wafer W is reduced compared to step S7, thereby suppressing the thinning of the bottom portion of the resist pattern obtained through development.

[0192] Furthermore, in Example 1 of the processing flow, both PEB processing and developing processing are performed by the developing unit 200. In this case, the wafer is not removed from the developing unit 200 (processing container 300), but the two processes are performed consecutively. Therefore, it is possible to suppress the time from the end of PEB processing to the start of developing processing, which varies for each wafer W.

[0193] Furthermore, in the above example, when PEB processing and a development process including heating of wafer W are continuously performed using the same developing unit 200, during the development process, wafer W is brought closer to the hot plate 360 ​​than during PEB processing, thereby increasing the processing temperature of wafer W during the development process compared to PEB processing. Therefore, it is possible to increase the processing temperature of wafer W during the development process compared to PEB processing while keeping the set temperature of the hot plate 360 ​​constant. Thus, it is not necessary to change the set temperature of the hot plate for PEB processing after the development process, and there is no need to wait until the hot plate temperature reaches the set value after a temperature change. Therefore, according to this example, when PEB processing and a development process including heating of wafer W are continuously performed using the same developing unit, the throughput can be improved when the processing temperature of wafer W during the development process is higher than that during PEB processing.

[0194] The developing apparatus of this embodiment includes: a vaporizer 501 serving as a developing fluid generation unit, which generates a developing fluid containing a weak acid gas from a developing liquid; and a developing unit 200 having a chamber 320 for developing a wafer W using the developing fluid. The chamber 320 forms a processing space K1 for housing the wafer W, and the processing space K1 is provided with a discharge port 331 for discharging the developing fluid. Furthermore, in this developing apparatus, the developing unit 200, in addition to discharging the developing fluid from the discharge port 331 toward the surface side of the wafer W within the processing space K1, also has other discharge ports 360d for discharging a predetermined gas (specifically, an inactive gas) toward the back side of the wafer W within the processing space K1. Therefore, in the developing unit 200, during development, a predetermined gas (specifically, an inactive gas) can be discharged toward the back side of the wafer W within the processing space K1, thereby suppressing the spread and adhesion of products generated during development to the back side of the wafer W. Therefore, developing with a developing fluid containing a weak acid gas can be performed effectively.

[0195] Furthermore, in this embodiment, a heat exchanger 364 is provided in the developing unit 200 as a heating unit for heating a predetermined gas (specifically, an inactive gas) emitted toward the back side of the wafer W within the processing space K1. Therefore, during development, it is possible to prevent the wafer W from being cooled by the predetermined gas ejected onto it. In particular, it is possible to prevent the wafer W, which is heated during development, from being cooled by the predetermined gas during development.

[0196] Furthermore, in this embodiment, the developing unit 200 also includes a hot plate 360 ​​that supports the wafer W within the processing space K1. A groove 360e, which is annular in plan view, is formed on the upper surface of the hot plate 360. Specifically, the groove 360e is formed on the upper surface of the main body 360a of the hot plate 360. An outlet 360d is formed at the bottom of the groove 360e. Therefore, it is possible to suppress the circumferential deflection of the purge gas emitted from the outlet 360d.

[0197] The supply mechanism 500 of this embodiment, serving as a developing fluid supply device, includes a supply path 502 connected to the developing unit 200, a vaporizer 501 serving as a developing fluid generation unit, and a heater 503 serving as a heating unit for heating the developing fluid supplied to the developing unit 200 via the supply path 502. To appropriately advance the development of a wafer W containing a metal resist using a developing fluid containing a weak acid gas, it is preferable that the temperature of the developing fluid reaching the wafer W within the developing unit 200 is higher than room temperature; specifically, it is preferable that it is approximately the same as the temperature of the heated wafer W. Because the supply mechanism 500 includes the heater 503, the temperature of the developing fluid reaching the wafer W can be made to the temperature described above. That is, according to the supply mechanism 500 of this embodiment, a developing fluid containing a weak acid gas suitable for developing metal resists can be supplied.

[0198] Furthermore, as described above, a portion of the supply mechanism 500 including the vaporizer 501 and the concentration sensor 550 can be modularized. Moreover, the block BL including the vaporizer 501 and the concentration sensor 550 can be configured such that it is positioned at the same height as the developing unit 200, the destination of the developing fluid supply. This shortens the distance of the supply path 502 from the vaporizer 501 to the developing unit 200. As a result, the temperature of the supply path 502, where condensation of the developing fluid occurs when the temperature drops, can be easily managed. Additionally, the time from changing the concentration of the weak acid in the developing fluid generated by the vaporizer 501 to the actual change in the concentration of the weak acid in the developing fluid supplied to the developing unit 200 can be shortened; that is, the control responsiveness of the weak acid concentration in the developing fluid can be improved.

[0199]

[0200] In the above example, the emission of inactive gas from the hot plate 360 ​​(specifically, the emission of inactive gas from the hot plate 360 ​​to the back side of the wafer W) is performed from the emission port 360d, which is separate from the through hole 372 through which the lifting pin 370 is inserted. Alternatively, or otherwise, the emission of inactive gas from the hot plate 360 ​​(specifically, the emission of inactive gas from the hot plate 360 ​​to the back side of the wafer W) can also be performed from the through hole 372. In this case, the same component as the aforementioned inactive gas supply mechanism 363 is connected to the through hole 372.

[0201] <Example 2 of the processing flow>

[0202] Figure 13 This is a flowchart of the main steps of Example 2, which represents the processing flow performed by the wafer processing system 1.

[0203] In this example, unlike Example 1 of the processing flow, after the development process using a developing fluid, i.e., after step S8, the wafer W is subjected to ultraviolet irradiation treatment to modify the residue on the wafer W after development (step S11). Then, the modified residue is removed using a removal liquid (step S12).

[0204] In step S11, specifically, the developed wafer W is supported by the wafer transport device 33 and transported to the ultraviolet irradiation device within the processing station 3 for ultraviolet irradiation processing. The ultraviolet irradiation device is, for example, located in the second block G2 of the processing station 3, similar to the heat treatment device. The ultraviolet irradiation processing involves irradiating the entire upper surface, or the entire facet, of the wafer W with ultraviolet light; specifically, it involves irradiating the entire facet of the wafer W with ultraviolet light without a mask. Furthermore, "the entire facet of the wafer W" includes at least the entire device formation area of ​​the wafer W. The wavelength of the ultraviolet light used in the ultraviolet irradiation processing is longer than that of EUV light, for example, 100 nm or more but less than 300 nm. Additionally, the ultraviolet irradiation processing is performed, for example, in an atmospheric atmosphere.

[0205] By using this ultraviolet irradiation treatment, the unexposed portions of the metal-containing photoresist remaining on the wafer W after development are modified. Specifically, in the unexposed portions of the metal-containing photoresist on the wafer W, after ultraviolet irradiation, the bonds between the metal and ligands in the residual metal-containing photoresist break (i.e., ligand detachment), and the photoresist becomes hydroxylated, i.e., hydrophilic. Conversely, the exposed portions of the metal-containing photoresist on the wafer W become hydrophobic due to dehydration condensation, making it difficult to achieve the hydrophilicization described above through ultraviolet irradiation.

[0206] In step S12, specifically, the wafer W after UV irradiation is supported by the wafer transport device 33 and transported to the removal device in the processing station 3, where a removal liquid is used to remove residues on the modified wafer W. The removal device is, for example, provided in the second block G1 of the processing station 3, similar to the resist film forming device. A polar solution is used as the removal liquid; specifically, an aqueous solution is used, and more specifically, an aqueous solution of tetramethylammonium hydroxide (TMAH) is used. Most or all of the metal resist residues on the wafer W, which have been hydrophilized by UV irradiation, are present in the unexposed areas and dissolve in this polar solution, thus being removed from the wafer W. Furthermore, as mentioned above, the exposed areas of the wafer W containing metal resist are less likely to become hydrophilized, thus maintaining low polarity and not dissolving in polar solutions, and are not removed from the wafer. If UV irradiation before development is considered, it may be necessary to investigate means for adjusting the degree of hydrophilization in areas near pattern boundaries, such as intermediate exposed areas within the metal resist, in order to stabilize the pattern roughness. That is, since ultraviolet treatment is performed after the pattern is formed by development, the risk of deterioration of pattern roughness can be suppressed, and the residue can be modified.

[0207] Example 2 of the processing flow further includes: after the development process, subjecting the wafer W to ultraviolet irradiation treatment to modify the developed residue on the wafer W (step S11); and then removing the modified residue using a removal solution (step S12). According to the example of the processing flow, the developed residue on the wafer W can be reduced, thus enabling better development, specifically, resulting in a better resist pattern.

[0208] Furthermore, steps S11 and S12 are performed, for example, between steps S8 and S9.

[0209] <Example 3 of the processing flow>

[0210] Figure 14 This is a flowchart of the main steps of Example 3, which represents the processing flow performed by the wafer processing system 1.

[0211] In this example, unlike Example 1 of the processing flow, after the development process using the developing fluid, i.e., after step S8, the wafer W is inspected (step S21). Based on the inspection result, the processing conditions in the development process, i.e., the processing conditions in steps S7 and S8, are corrected by the control unit 100, which is a correction unit (step S22).

[0212] In step S21, specifically, the developed wafer W is transported to the inspection device within the wafer processing system 1 using a wafer transport device 33 or the like, and then inspected. Specifically, for example, the entire upper surface of the wafer W is photographed using the inspection device, and an image of the wafer W based on the photographing result is obtained by the control unit 100.

[0213] In step S22, specifically, for example, the control unit 100 corrects the processing conditions in steps S7 and S8 for subsequent wafers W based on the image of the wafer W, which is the inspection result in step S21. The correction is performed, for example, in a way that the development result of the developing fluid becomes more uniform within the plane of the wafer W.

[0214] The corrected processing conditions are those that affect the critical dimension (CD) of the metal resist pattern obtained through development, such as the heat output of heaters 360b in regions R1 to R5 of the hot plate 360. If a small portion of the metal resist pattern exists within the developed wafer W, correction is performed by reducing the heat output of any one of the heaters 360b in regions R1 to R5 of the hot plate 360 ​​corresponding to that portion. By adjusting the heat output in any one of regions R1 to R5 of the hot plate 360, the intensity of the resist film removal action of the developing fluid changes in the region corresponding to the metal resist pattern, thereby controlling the pattern size. The metal resist undergoes a condensation reaction to achieve an insoluble state in the developing fluid, unlike conventional chemically amplified resists. Regarding the PEB reaction, the moisture around the metal resist film has a significant impact, but the pattern size does not change sensitively with temperature changes during PEB itself. Therefore, it is difficult to adjust the pattern size by controlling the temperature or temperature distribution when applying PEB to a film containing metal resist.

[0215] For the reasons stated above, in order to adjust the pattern size containing the metal resist, compared with temperature control during PEB, the method of adjusting the removal effect of the developing fluid on the unexposed portion of the metal resist film by adjusting the temperature conditions during development makes it easier to change the pattern size and adjust it to the desired pattern size, and is therefore preferred.

[0216] Alternatively, the corrected processing condition can also be the temperature of the inactive gas emitted from the outlet 360d.

[0217] Furthermore, the corrected processing condition can also be the distribution of the concentration of the developing fluid within the processing space K1. Specifically, it can be the ratio (balance) of the exhaust volume of the processing space K1 via the central exhaust path 340 to the exhaust volume of the processing space K1 via the peripheral exhaust path 350, which affects the concentration distribution. According to the inventors' repeated experiments, if the exhaust volume of the processing space K1 via the central exhaust path 340 is large, the concentration of the developing fluid within the processing space K1 becomes higher above the center of the wafer W, making it easier for the developing fluid in the center of the wafer W to advance. On the other hand, if the exhaust volume of the processing space K1 via the peripheral exhaust path 350 is large, the concentration of the developing fluid within the processing space K1 becomes higher above the periphery of the wafer W, making it easier for the developing fluid in the periphery of the wafer W to advance. Therefore, when the size of the pattern containing metal resist at the periphery of the developed wafer W is large, the above-mentioned balance is corrected by increasing the exhaust volume of the processing space K1 via the peripheral exhaust path 350.

[0218] According to Example 3 of the processing procedure, the shape of the resist pattern after development can be made closer to the desired pattern shape. Specifically, according to Example 3 of the processing procedure, the shape of the metal resist pattern obtained by development can be made uniform within the wafer surface.

[0219] Furthermore, step S21 is performed, for example, between steps S8 and S9, and step S22 is performed, for example, after step S21 and during the period up to step S1 for the next wafer W.

[0220]

[0221] In the above example, the correction of the processing conditions in the developing process using the developing fluid is based on the inspection results of the wafer W after the developing process, i.e., after development by the developing unit 200. Alternatively, the correction of the processing conditions in the developing process using the developing fluid can also be based on any of the following.

[0222] • The state of wafer W during development (specifically, during steps S7 and S8, i.e., during development by the developing unit 200) (e.g., the temperature distribution of wafer W).

[0223] • The state of the developing unit 200 during development (e.g., the output of heater 360b to each region R1 to R5 of the hot plate 360).

[0224] • Inspection results of the wafer after subsequent processes performed on the developed wafer W (e.g., etching using the developed resist pattern as a mask).

[0225] • The state of wafer W during the subsequent processes described above (e.g., the temperature distribution of wafer W).

[0226] • The state of the subsequent processing unit during the above-mentioned subsequent processes (e.g., the temperature distribution of the heating unit that supports and heats the wafer during etching in an etching apparatus that uses the developed resist pattern as a mask).

[0227] Furthermore, when using the temperature distribution of wafer W as the state of wafer W during development, the temperature of wafer W during development can be obtained, for example, by using a temperature sensor provided on the lifting pin 370 and the protrusion 360c of the hot plate 360.

[0228] For example, if a temperature distribution of wafer W is obtained such that the periphery of wafer W becomes low due to the emission of inactive gas from the outlet 360d, the above-mentioned balance of exhaust volume is corrected by increasing the exhaust volume of the processing space K1 via the outer peripheral exhaust path 350.

[0229] Alternatively, if the temperature measurement result of the temperature sensor located on the lifting pin 370 on the wafer W differs from the temperature measurement result of the temperature sensor located on the protrusion 360c located further out than the lifting pin 370 on the wafer W, the development processing conditions can be corrected (adjusted) to compensate for the difference in measurement results. In this case, the development processing conditions corrected include the aforementioned balance of exhaust volume, the temperature of the inactive gas discharged from the discharge port 360d, etc.

[0230] <Example 4 of the processing flow>

[0231] Figure 15 This is a flowchart of the main steps of Example 4, which represents the processing flow performed by the wafer processing system 1.

[0232] In this example, unlike Example 1 of the processing flow, after the development process using the developing fluid, i.e., after step S8, purification is performed within the processing container 300. Specifically, after step S8, with the wafer W not located within the processing space K1, the aforementioned developing fluid, as a cleaning fluid containing a weak acid gas, is supplied to the processing space K1 (step S31).

[0233] In step S31, specifically, for example, after the developed wafer W is discharged from the processing container 300 in step S8, the upper chamber 321 descends, the interior of the chamber 320 is sealed, and the processing space K1 is formed again. Then, a developing fluid, whose temperature and weak acid concentration are adjusted to the required values, is discharged from the spray head 330 (specifically, the discharge port 331) to the surface side of the wafer W as a cleaning fluid. Additionally, at least one of the following is performed: exhaust from the processing space K1 via the central exhaust path 340 and exhaust from the processing space K1 via the peripheral exhaust path 350. As a result, the components of the developing unit 200 exposed within the processing space K1 (e.g., the hot plate 360, the chamber 320) are exposed to an acidic atmosphere containing a weak acid gas. Consequently, the developing products adhering to these components react with the weak acid gas to become low-molecular-weight, and then vaporize due to heat, etc. The vaporized product is discharged outside the processing space K1 through the exhaust from the processing space K1.

[0234] According to Example 4 of the processing procedure, it is possible to suppress the deterioration of the cleanliness of chamber 320, etc., due to development.

[0235] Furthermore, step S31 can be performed on each wafer W, or on a per-wafer-wheat ...

[0236] Furthermore, in step S31, the removal capacity of the resist (specifically, a metal-containing resist) in the developing fluid supplied as the cleaning fluid can be improved compared to the developing fluid supplied during development in steps S7 and S8. Specifically, at least one of the following can be satisfied.

[0237] • The supply flow rate of the developing fluid, which is used for cleaning, is high.

[0238] • The temperature of the developing fluid used for cleaning is low.

[0239] • The concentration of weak acid in the developing fluid used for cleaning is low.

[0240] • The weak acid in the developing fluid used for cleaning has a small acid dissociation constant (pka).

[0241] • A weakly developing substance is added to the developing fluid during development, in a mixed solution containing a weak acid that is to be vaporized in the supply unit 500.

[0242] Therefore, cleaning can be performed in a short time, that is, the products generated during development can be removed from the components of the developing unit 200 exposed in the processing space K1.

[0243] When the weak acid in the developing fluid used for cleaning has a small acid dissociation constant (pka), that is, when the types of weak acid gases contained in the developing fluid are different, the supply mechanism for the developing fluid used for cleaning and the supply mechanism for the developing fluid used during development can be set up separately.

[0244]

[0245] In step S31, during the discharge of the developing fluid, which is used for cleaning, from the spray head 330, an inactive gas can be discharged from the hot plate 360. Specifically, the inactive gas can be discharged from at least one of the discharge port 360d and the through hole 372.

[0246]

[0247] The inventors evaluated a variation of Example 4 of the processing flow. In this evaluation, after developing a wafer W with a metal resist film formed on it using a developing fluid, the wafer W was removed from the processing container 300. Subsequently, multiple other wafers W without a resist film were sequentially placed into the processing container 300, subjected to a specific purification process, and removed from the processing container 300. The specific purification process involved discharging a developing fluid (specifically, a discharge port 331) as a cleaning fluid from a spray head 330 for the same duration as the developing process, and discharging an inactive gas (specifically, nitrogen) from a hot plate 360 ​​(specifically, a through hole 372) onto the lower surface of the wafer W. Furthermore, in the above evaluation, each wafer W after the specific purification process was removed from the processing container 300, and the amount of metal components present on the surface of the wafer W was checked.

[0248] Figure 16 This is a graph showing the evaluation results of the above-mentioned modified example of Example 4, representing the processing flow. Figure 16 In the diagram, the horizontal axis represents the total number of times the specific cleaning process was performed on the wafer W to be inspected for metal composition, i.e., the number of times the specific cleaning process was performed after the development process. The vertical axis, with the amount of metal composition detected after the first specific cleaning process as 1.0, represents the amount of (residual) metal composition present on the wafer W after the specific cleaning process as the residual rate.

[0249] like Figure 16As shown, after the third specific purification treatment, the residue rate was below 0.5 (specifically, approximately 0.46), and after the sixth specific purification treatment, the residue rate was approximately 0.2. This indicates that the amount of residual metal components decreased with repeated specific purification treatments. The detected metal components can be attributed to metal residue released into the processing container 300 due to the development treatment of the metal-containing resist. Therefore, it can be said that by performing the normalization treatment described above after developing the metal-containing resist film, the metal residue in the processing container 300 can be reduced. Furthermore, from... Figure 16 It is known that the longer the duration of a specific purification process is extended, the more metal residue can be reduced.

[0250] <Another example of a fluid supply mechanism for developing>

[0251] Figure 17 This is a diagram illustrating another example 1 of a fluid supply mechanism for developing.

[0252] Figure 17 In addition to the concentration sensor 550, the developing fluid supply mechanism 500A also has a dilution path 560. The dilution path 560 is connected to the supply path 502 and supplies an inactive gas to the supply path 502. This inactive gas is used to dilute the developing fluid supplied to the developing unit 200 via the supply path 502.

[0253] One end of the dilution path 560 is connected to the supply path 502, and the other end is connected to the supply source 561 of the inert gas used as the dilution gas. Furthermore, a supply equipment assembly 563 is provided in the dilution path 560, including an on / off valve for controlling the flow of the inert gas within the dilution path 560 and a gas flow regulating valve 563a for regulating the flow rate of the inert gas. The supply equipment assembly 563 is controlled by the control unit 100.

[0254] In the supply mechanism 500A, the flow rate of the inactive gas supplied from the dilution path 560 to the supply path 502 is adjusted by control unit 100 based on the measurement results of concentration sensor 550. For example, if the concentration of weak acid in the mixed solution in tank 521 is high, and the concentration of weak acid in the developing fluid generated by vaporization by vaporizer 501 (i.e., the concentration of weak acid measured by concentration sensor 550) is also high, the flow rate of the inactive gas supplied from the dilution path 560 to the supply path 502 is reduced. On the other hand, if the concentration of weak acid in the mixed solution in tank 521 decreases over time, and the concentration of weak acid in the developing fluid generated by vaporization by vaporizer 501 (i.e., the concentration of weak acid measured by concentration sensor 550) becomes low, the flow rate of the inactive gas supplied from the dilution path 560 to the supply path 502 is increased.

[0255] Therefore, regardless of the concentration of the weak acid in the mixed solution in tank 521, the concentration of the weak acid in the developing fluid supplied to the developing unit 200 via supply path 502 can be kept constant.

[0256] <Another example 2 of a developing fluid supply mechanism>

[0257] Figure 18 This is another example 2 used to illustrate the supply mechanism for the developing fluid.

[0258] exist Figure 18 In the developing fluid supply mechanism 500B, a concentration sensor 570 is provided for the tank 521 storing a mixed solution of weak acid and organic solvent to detect the concentration of the weak acid in the mixed solution.

[0259] Furthermore, in the supply mechanism 500B, tank 581 is connected to tank 521 via supply path 582. The concentration of the weak acid in the liquid stored in tank 581 is higher than the initial concentration of the weak acid in the mixed solution in tank 521. For example, if the mixed solution stored in tank 521 is a liquid with an acetic acid concentration of 40%, the liquid stored in tank 521 is a liquid with an acetic acid concentration of 100%.

[0260] One end of the supply path 582 is connected to tank 521, and the other end is connected to tank 581. Additionally, a supply equipment assembly 583 is provided in the supply path 582, including an on / off valve for controlling the flow of the medicinal liquid within the supply path 582, and a liquid flow regulating valve 583a for regulating the flow rate of the medicinal liquid. The supply equipment assembly 583 is controlled by the control unit 100.

[0261] In the supply mechanism 500B, the control unit 100 controls the supply of a high-concentration drug solution from tank 581 to tank 521 based on the measurement results of the concentration sensor 570, so that even if the concentration of the weak acid in the mixed solution in tank 521 decreases over time, the concentration will remain within a specified range.

[0262] Therefore, the concentration of the weak acid in the mixed solution in tank 521 can be kept approximately constant, and thus the concentration of the weak acid in the developing fluid supplied to the developing unit 200 via supply path 502 can be adjusted to be approximately constant.

[0263] <Another example 3 of a developing fluid supply mechanism>

[0264] Figure 19 This is another example 3 of the diagram used to illustrate the supply mechanism for the developing fluid.

[0265] As described above, the vaporizer 501 can continuously generate developing fluid. Furthermore, the mixed solution of acid and organic solvent, which serves as the source of the developing fluid, can also be recycled. That is, the developing liquid can also be recycled.

[0266] Figure 19 For the circulation of the developing liquid, the developing fluid supply mechanism 500C has a return path 590 connected to one end of a drain tank 530, which also functions as a condenser as described above. The return path 590, together with the branch path 505, constitutes the developing liquid circulation path J. For example, a pump 591 for pressurizing the developing liquid and a filter 592 for filtering the developing liquid are provided in the return path 590.

[0267] Alternatively, an exhaust pipe 593 can be installed to vent air from the drain tank 530.

[0268] In the supply mechanism 500C, for example, while the vaporizer 510 continuously generates developing fluid, it flows into the circulation path J. The developing liquid, which is condensed and regenerated by the drain tank 530, is returned to the vaporizer 501 via the pump 591 and the filter 592. Then, when it is necessary to supply developing fluid to the developing unit 200, the developing fluid flows into the main stream of the supply path 502, which is located on the side of the on / off valve 504.

[0269] By continuously generating developing fluid from vaporizer 501, the concentration and temperature of the developing fluid can be stabilized, thus stabilizing the developing performance. Furthermore, since the developing fluid is returned to vaporizer 501 via circulation path J, the consumption of developing liquid can be suppressed.

[0270] Furthermore, the downstream side of the connecting portion of the branch path 505 in the supply path 502 (i.e., the connecting portion of the loop path J) can branch into multiple branches, and each branch path after the branching is connected to a different developing unit 200. That is, if the downstream side of the portion of the supply path 502 that branches into the branch path 505 is regarded as the main supply path, multiple main supply paths that are respectively connected to multiple developing units 200 can be connected at the aforementioned branch portion.

[0271] Furthermore, the developing liquid used as the developing fluid can be a 100% acid liquid without any organic solvent. This allows for the suppression of changes in the acid concentration in the developing fluid caused by variations in the acid concentration in the developing liquid.

[0272] <Other examples of methods for changing the temperature of wafer W during PEB processing and development>

[0273] Unlike the examples above, not only during development in steps S7 and S8, but also during the PEB processing in step S6, a specified gas (inactive gas) can be discharged from the discharge port 360d, and the heat exchanger 364 is controlled so that the temperature of the inactive gas discharged during PEB processing is lower than that during development. Therefore, the temperature of the wafer W during PEB processing can also be lower than that during development.

[0274] <Other examples of methods for expelling cryogenic gas from a 360° outlet>

[0275] Figure 20 The figure is a partial enlarged cross-sectional view schematically showing the structure of the periphery of the hot plate 360, used to illustrate another example of the method of discharging cryogenic gas from the outlet 360d.

[0276] exist Figure 20 In the example, in addition to supply path 362, which serves as a high-temperature supply path, low-temperature supply path 365 is connected to outlet 360d, wherein the high-temperature supply path is used to supply outlet 360d with a specified gas (inactive gas) heated by heat exchanger 364.

[0277] The cryogenic supply path 365 is separate from the supply path 362, supplying a specified gas (inactive gas) at a lower temperature than the specified gas (inactive gas) supplied from the supply path 362 to the discharge port 360d. Specifically, the cryogenic supply path 365, for example, is separate from the supply path 362, supplying a specified gas (inactive gas) that has not been heated by the heat exchanger 364 to the discharge port 360d. The discharge port 360d is connected to the inactive gas supply mechanism 366 via the cryogenic supply path 365. Although not shown in the figure, the supply mechanism 366, for example, has a supply device assembly including a supply source of inactive gas, an on / off valve for controlling the flow of inactive gas, and a flow regulating valve.

[0278] In such Figure 20 In this configuration, during the PEB processing in step S6, low-temperature gas supplied via low-temperature supply path 365 is discharged from the discharge port 360d, and during the development processes in steps S7 and S8, high-temperature gas supplied via supply path 362, which serves as a high-temperature supply path, is discharged from the discharge port 360d. This allows the temperature of the wafer W during PEB processing to be lower than that during development.

[0279] According to this structure, the temperature of a specified gas (inactive gas) emitted from the outlet 360d can be rapidly increased to a higher temperature. Therefore, the temperature of the wafer W can be rapidly raised from a temperature suitable for PEB processing to a temperature suitable for development.

[0280] Furthermore, the confluence of supply path 362 and cryogenic supply path 365 is preferably located near the outlet 360d, for example, directly below the hot plate 360. This allows the specified gas (inactive gas) discharged from the outlet 360d to be heated to a higher temperature more quickly.

[0281] <Other examples of methods for reducing the amount of developing fluid used in development>

[0282] Figure 21 This is a diagram illustrating another example of a method for reducing the development of the developing fluid during development.

[0283] In this example, the spray head 330 of the developing unit 200 is connected to multiple supply mechanisms, each including a developing fluid generation unit. Figure 21 In the example, two supply mechanisms 600 and 601 are connected to the spray head 330 of the developing unit 200. Each of the supply mechanisms 600 and 601 is configured in the same way as the supply mechanism 500 described above.

[0284] Furthermore, in this example, the two supply mechanisms 600 and 601 supply developing fluid to the developing unit 200 in such a way that the developing intensity of the supplied developing fluid is the same as that of each other. Specifically, the supply mechanism 600 for relatively strong developing of the developing fluid and the supply mechanism 601 for relatively weak developing of the developing fluid satisfy at least one of the following.

[0285] • The supply flow rate of the developing fluid from the supply unit 601 is low.

[0286] • The temperature of the developing fluid supplied by the supply unit 601 is low.

[0287] • The concentration of weak acid in the developing fluid supplied by supplier 601 is low.

[0288] • In supply mechanism 600, no weakly developing substance is added to the mixed solution containing a weak acid to be vaporized; in supply mechanism 601, a weakly developing substance is added to the mixed solution.

[0289] Then, in step S7 above, developing fluid is supplied to the developing unit 200 from the relatively strong developing fluid supply mechanism 600, and in step S8 above, developing fluid is supplied to the developing unit 200 from the relatively weak developing fluid supply mechanism 601. That is, when transitioning from step S7 to step S8, the supply source of developing fluid to the developing unit 200 is switched from supply mechanism 600 to supply mechanism 601.

[0290] According to this method, the developing fluid can be changed to the required intensity more quickly.

[0291] <Other examples of gas being expelled from outlet 360d towards the back periphery of wafer W>

[0292] Figure 22 This is a diagram used to illustrate an example of gas being expelled from the outlet 360d, and is a schematic, partially enlarged cross-sectional view showing the structure of the periphery of the hot plate 360.

[0293] exist Figure 22 In the example, a supply mechanism 700 for a cleaning fluid containing a weak acid gas is connected to the outlet 360d of the hot plate 360, similar to the supply mechanism for the developing fluid. Therefore, the cleaning fluid can be discharged from the outlet 360d.

[0294] The supply mechanism 700 is configured similarly to the supply mechanism 500, except that the destination of the supply path 502 is the outlet 360d instead of the spray head 330, and that the fluid generated and supplied is a cleaning fluid instead of a developing fluid. Alternatively, a portion such as the vaporizer 501 may be shared between the supply mechanism 700 connected to the outlet 360d and the supply mechanism 500 connected to the spray head 330.

[0295] In such Figure 22 In such a configuration, in step S31 of Example 4 of the processing flow, the cleaning fluid may be discharged from the outlet 360d in addition to the developing fluid being discharged from the spray head 330 as the cleaning fluid. Alternatively, the developing fluid being discharged from the spray head 330 as the cleaning fluid and the cleaning fluid being discharged from the outlet 360d may be alternately discharged. In this case, the cleaning fluid may be discharged from the outlet 360d first. In addition, in the case of alternating operation, for example, by discharging the cleaning fluid from the outlet 360d, dirt in the fine structural parts of the upper part of the chamber 320 is flushed out. On the other hand, by discharging the developing fluid as the cleaning fluid from the spray head 330, the periphery of the spray head 330 and the inner wall of the chamber 320 can be cleaned.

[0296] <Example of a process flow where cleaning fluid is discharged from a 360-degree outlet>

[0297] Figure 23 This is a flowchart illustrating the main steps of a process flow example where cleaning fluid is discharged from outlet 360d.

[0298] In this example, unlike Example 1 of the processing flow, after the developing process using developing fluid, cleaning fluid is discharged from the discharge port 360d of the hot plate 360 ​​to the back side of the wafer W (step S41).

[0299] In step S41, specifically, for example, after the discharge of the developing fluid in step S8 stops, before the wafer W is sent out of the chamber 320, the cleaning fluid is discharged from the discharge port 360d of the hot plate 360 ​​to the peripheral back side of the wafer W. Furthermore, at least one of the venting of the processing space K1 via the central venting path 340 and the venting of the processing space K1 via the outer peripheral venting path 350 continues. As a result, the peripheral back side of the wafer W is exposed to an acidic atmosphere containing a weak acid gas. Consequently, the developing products adhering to the peripheral back side of the wafer W react with the weak acid gas to become low-molecular-weight, and then vaporize due to heat, etc. The vaporized product is discharged out of the processing space K1 via the venting of the processing space K1.

[0300] According to the processing flow of this example, in the process of developing using a developing fluid, even if the product generated during development spreads to and adheres to the back periphery of the wafer W, the product generated during development can be removed using a cleaning fluid.

[0301] The cleaning fluid can be supplied in a manner that enhances the removal capacity of the resist (specifically, a metal-containing resist) compared to the developing fluid supplied during development in steps S7 and S8. Specifically, at least one of the following conditions can be met.

[0302] • The supply flow rate of the cleaning fluid is greater than that of the developing fluid.

[0303] • The temperature of the cleaning fluid is higher than that of the developing fluid.

[0304] • The concentration of weak acid in the cleaning fluid is higher than that in the developing fluid.

[0305] • No weakly developing substances are added to the raw material mixture in the cleaning fluid, while a weakly developing substance is added to the raw material mixture in the developing fluid.

[0306]

[0307] In the above example, the process of discharging the cleaning fluid from the outlet 360d of the hot plate 360 ​​to the back side of the wafer W (step S41) is performed after the development process using the developing fluid. Alternatively, the process of discharging the cleaning fluid (step S41) can also be performed later in the development process using the developing fluid.

[0308] Specifically, in step S8, while the developing fluid is being ejected from the spray head 330, the cleaning fluid begins to be ejected from the outlet 360d of the hot plate 360 ​​toward the back side of the wafer W.

[0309] According to this modified example, the time required from the completion of the development process using a developing fluid to the removal of the developing product from the back periphery of the wafer W (i.e., cleaning of the back periphery of the wafer W) can be shortened.

[0310] <Other examples of vaporizers>

[0311] Figure 24 This is a longitudinal cross-sectional view used to illustrate other examples of vaporizers.

[0312] Figure 24 The vaporizer 501A has a chamber 800, which is divided into a mixing space K11 (described later) and a discharge preparation space K12 that is adjacent to the mixing space K11 in the horizontal direction.

[0313] A nozzle 811, serving as a dispensing section for dispensing developing liquid, is provided on the top wall 801 of the chamber 800. Furthermore, a supply path 812 extending from the nozzle 811 is formed within the top wall 801. The supply path 812 is connected to a developing liquid supply mechanism 814 via a supply pipe 813. Although not shown in the figure, the supply mechanism 814, for example, includes a supply device assembly comprising a supply source for developing liquid, an on / off valve for controlling the flow of developing liquid, and a flow regulating valve. This supply device assembly is controlled by the control unit 100.

[0314] The amount of developing liquid ejected from nozzle 811 at one time is the amount corresponding to one development of the developing fluid, which is a few ml, a relatively small amount.

[0315] Furthermore, a spray plate 821 with multiple discharge ports 822 is provided on the top wall 801. The discharge ports 822 discharge an inactive gas, which serves as a carrier gas, into the mixing space K11 between the spray plate 821 and the diffuser 831 (described later). The aforementioned nozzle 811 is installed on the spray plate 821, for example, extending downward from the center of the lower surface of the spray plate 821.

[0316] Additionally, a diffusion space K21 communicating with multiple discharge ports 822 and a supply path 823 extending from the diffusion space K21 are formed within the top wall 801. A supply mechanism 825 for inert gas is connected to the supply path 823 via a supply path 824. Although not shown in the figure, the supply mechanism 825 includes, for example, a supply device assembly comprising a supply source for the inert gas, an on / off valve for controlling the flow of the inert gas, and a flow regulating valve. This supply device assembly is controlled by the control unit 100.

[0317] The bottom wall 802 of chamber 800, facing the spray plate 821, forms a diffuser section 831.

[0318] The diffuser section 831 receives a small amount of developing liquid ejected from the nozzle 811, allowing the developing fluid to spread horizontally. The diffuser section 831 achieves this horizontal spreading of the developing fluid, for example, through capillary action. For instance, by using a component with a finely constructed, continuously connected structure in the portion of the bottom wall 802 corresponding to the diffuser section 831, the horizontal spreading of the developing fluid can be achieved within the diffuser section 831 using capillary action. Furthermore, the diffuser section 831 can also be surface-modified through plasma treatment, hydrophilic coating, or other methods to promote the diffusion of the developing liquid.

[0319] Additionally, a partition wall 832 is provided on the bottom wall 802 of the chamber 800. The partition wall 832, the diffuser 831, and the side wall 803 of the chamber 800 form a storage space for receiving the developing liquid ejected from the nozzle 811.

[0320] A partition wall 832 separates the leakage-receiving space on the bottom wall 802 of the chamber 800 from the aforementioned receiving space. The leakage-receiving space receives developing liquid that leaks out when not fully contained within the receiving space. Furthermore, although not shown in the figure, a drain pipe may be provided to discharge the developing liquid from the leakage-receiving space to the outside. The drain pipe may extend from the leakage-receiving space and be installed on the top wall 801, for example.

[0321] Furthermore, a heater 840 is provided in the bottom wall 802 of the chamber 800 for heating the developing liquid that is received by the diffusion section 831 and stored in the storage space.

[0322] Additionally, a discharge outlet 850 is provided in the portion of the top wall 801 of the chamber 800 above the discharge preparation space K12, which is adjacent to the aforementioned mixing space K11. A supply path 502 is connected to the discharge outlet 850.

[0323] In vaporizer 501A, the developing liquid, which is discharged from nozzle 811 and diffused by diffuser 831, is heated and vaporized by heater 840. The vaporized developing liquid is mixed with inert gas discharged from outlet 822 in mixing space K11. The mixture of vaporized developing liquid and inert gas is supplied to developing unit 200 as developing fluid via discharge preparation space K12, outlet 850 and supply path 502.

[0324] <Variation Example>

[0325] Furthermore, in the above examples, a fluid containing a weak acid gas was used as the developing fluid, but it is also possible to use a fluid containing a weak acid mist, or a fluid containing both a weak acid gas and a weak acid mist. That is, the developing fluid of this disclosure is a fluid containing at least one of a weak acid gas and a weak acid mist.

[0326] Similarly, in the above examples, a fluid containing weak acid gas was used as the cleaning fluid, but it is also possible to use a fluid containing weak acid mist, or a fluid containing both weak acid gas and weak acid mist.

[0327] In the above example, the distance between the wafer W and the main body 360a of the hot plate 360 ​​is adjusted by adjusting the lifting pin 370 supporting the wafer W. Alternatively, a structure in which the height of the protrusion 360c of the hot plate 360 ​​is adjustable can be adopted, and the above distance can be adjusted by adjusting the height of the protrusion 360c supporting the wafer W.

[0328] It should be understood that the embodiments disclosed herein are illustrative in all respects and are not restrictive. The above embodiments can be omitted, substituted, or modified in various ways without departing from the claimed technical solution and its spirit. For example, the constituent elements of the above embodiments can be arbitrarily combined. Based on such arbitrary combinations, the effects and functions of each constituent element involved in the combination can naturally be obtained, and other effects and functions that are obvious to those skilled in the art can be obtained from the description herein.

[0329] Furthermore, the effects described in this specification are merely illustrative or exemplary and are not intended to limit the scope of the invention. That is, the technology disclosed herein may provide other effects, besides those described above or in lieu of those described, that are obvious to those skilled in the art based on the description herein.

[0330] In addition, the following structural examples also fall within the technical scope of this disclosure.

[0331] (1) A developing method comprising a step of developing a substrate coated with a resist and subjected to exposure treatment, wherein the developing step comprises supplying a developing fluid generated from a developing liquid and containing at least one of a weak acid gas and a weak acid mist, wherein the concentration of the weak acid is adjusted, into a processing space, and developing the substrate in the processing space.

[0332] (2) The development method as described in (1) above, wherein, in the later stage of the development process, the development of the substrate by the developing fluid is reduced.

[0333] (3) The development method as described in (1) or (2) above, wherein the development step is a process of developing the substrate on which the resist film has been formed and which has undergone the exposure treatment and the heat treatment after the exposure treatment, and includes heating the substrate, wherein the temperature of the substrate during the heating in the development step is higher than the temperature of the substrate during the heat treatment after the exposure treatment.

[0334] (4) The development method as described in any one of (1) to (3) above, further comprising: after the development step, subjecting the substrate to ultraviolet irradiation treatment to modify the developed residue on the substrate; and subsequently removing the modified residue using a removal liquid.

[0335] (5) The development method as described in any one of (1) to (4) above, wherein, from the back side of the substrate into the processing space, a cleaning fluid comprising at least one of a weak acid gas and a weak acid mist is supplied after the development step or from the later stage of the development step.

[0336] (6) The development method as described in any one of (1) to (5) above, further comprising: supplying a cleaning fluid containing at least one of a weak acid gas and a weak acid mist into the processing space while the substrate is not located in the processing space.

[0337] (7) The development method as described in any one of (1) to (6) above, further comprising: a step of correcting the processing conditions in the development process based on the inspection result of the substrate after the development process, the state of the substrate or the developing unit during the development process, the inspection result of the substrate after the subsequent process performed on the substrate after the development process, or the state of the substrate or the subsequent process processing unit during the subsequent process.

[0338] (8) A developing apparatus for developing a substrate coated with a resist and subjected to exposure treatment, comprising: a developing fluid generating unit that generates a developing fluid containing at least one of a weak acid gas and a weak acid mist from a developing liquid, wherein the concentration of the weak acid is adjusted; and a developing unit having a chamber forming a processing space for receiving the substrate and having a discharge port for discharging the developing fluid provided in the processing space, wherein the developing fluid is used to develop the substrate.

[0339] (9) A readable computer storage medium storing a program that operates on a computer of a control unit that controls a developing apparatus to cause the developing apparatus to perform a developing method, wherein the developing method includes a step of developing a substrate coated with a resist and subjected to exposure treatment, wherein in the developing step, a developing fluid generated from a developing liquid that contains at least one of a weak acid gas and a weak acid mist, and the concentration of the weak acid is adjusted, is supplied to a processing space to develop the substrate in the processing space.

[0340] [Explanation of reference numerals in the attached figures]

[0341] 1. Wafer Processing System

[0342] 100 Control Department

[0343] 200 developing units

[0344] 320 chambers

[0345] 331 spit out

[0346] 501 and 501A vaporizers

[0347] K1 processing space

[0348] W wafers.

Claims

1. A developing method characterized by comprising a process of developing a substrate on which a resist film is formed and which has been subjected to an exposure process, in the developing process, a developing fluid containing at least either one of a weak acid gas and a weak acid mist and having a concentration of the weak acid adjusted is supplied into a processing space, and the substrate in the processing space is developed.

2. The developing method according to claim 1, characterized in that, in a later stage of the developing process, the developing fluid weakens development of the substrate.

3. The developing method according to claim 1 or 2, characterized in that, the developing process is a process of developing the substrate on which the resist film is formed and which has been subjected to the exposure process and a heating process after the exposure process, and includes heating of the substrate, the temperature of the substrate at the time of the heating in the developing process is higher than the temperature of the substrate at the time of the heating process after the exposure process. Further comprising:

4. The developing method according to claim 1 or 2, wherein a process of subjecting the substrate to an ultraviolet irradiation process after the developing process, and modifying a developed residue on the substrate; and a process of removing the modified residue using a removal liquid thereafter.

5. The developing method according to claim 1 or 2, characterized in that, a cleaning fluid containing at least either one of a weak acid gas and a weak acid mist is supplied into the processing space from the back surface side of the substrate after the developing process or from a later stage of the developing process. Further comprising:

6. The developing method according to claim 1 or 2, wherein a process of supplying a cleaning fluid containing at least either one of a weak acid gas and a weak acid mist into the processing space in a state where the substrate is not located in the processing space. Further comprising:

7. The developing method according to claim 1 or 2, wherein a process of correcting a processing condition in the developing process based on a result of inspection of the substrate after the developing process, a state of the substrate or a developing section at the time of the developing process, a result of inspection of the substrate after a post-process performed on the substrate after the developing process, or a state of the substrate or a post-process processing section at the time of the post-process. Including:

8. A developing apparatus for developing a substrate coated with a resist and subjected to exposure treatment, characterized in that, a developing fluid generation section that generates a developing fluid containing at least either one of a weak acid gas and a weak acid mist and having a concentration of the weak acid adjusted from a developing liquid; and a developing section that has a chamber forming a processing space in which the substrate is accommodated and in which a discharge port discharging the developing fluid is provided, and develops the substrate with the developing fluid. The readable computer storage medium stores a program that acts on a computer of a control section that controls a developing device to cause the developing device to execute a developing method, 9. A computer readable storage medium, characterized in that, the developing method includes a process of developing a substrate on which a resist film is formed and which has been subjected to an exposure process, in the developing process, a developing fluid containing at least either one of a weak acid gas and a weak acid mist and having a concentration of the weak acid adjusted is supplied into a processing space, and the substrate in the processing space is developed. ​

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