JP4917651B2 - Resist film removing apparatus and resist film removing method - Google Patents

Description

  The present invention relates to a resist removing apparatus and a resist removing method that are indispensable in a lithography process for forming a fine structure such as a semiconductor integrated circuit.

Currently, the resist film is removed by ashing and removing the resist film with oxygen plasma, and the resist film is heated and dissolved using an organic solvent (an organic solvent such as a phenol or halogen type, 90 ° C. to 130 ° C.). Or a heating dissolution method using concentrated sulfuric acid / hydrogen peroxide. Each of these methods requires time, energy, and chemical materials for decomposing and dissolving the resist film, and is a burden on the lithography process. Although there is a great demand for a new resist removal technique that can replace such removal by ashing or dissolution, the development of a stripping technique is still few. A typical example is a new technology that uses a high-frequency ultrasonic peeling action by developing a peeling liquid. For example, the peeling effect of “IPA-H ₂ O ₂ component system + salts such as fluoride” is recognized as the peeling solution.

  An object of the present invention is to peel off a resist film by utilizing physical property changes and structural changes of resist due to water vapor and ultraviolet rays. A resist film removing apparatus and a resist film removing method that realize an environmentally symbiotic technology that does not depend on a solvent.

  Specifically, the resist film is made of softening, expansion, hydration, swelling, solidification, and other physical properties such as water vapor and ultraviolet rays, and alteration due to structural changes such as cross-linking, oxidation, and decomposition. Select and act to remove the resist film.

  In other words, means for spraying water vapor, pressurized water and pressurized carbon dioxide gas onto the resist film (processing), means for adding chemical components to the water vapor and pressurized water (processing), means for heating and cooling the substrate (processing), ultraviolet light The resist film is removed by the effect of entanglement of means (treatment) or the like in terms of time / space, temperature and chemical.

The present inventors conducted research and development by taking up the following elemental technologies as problems.
Acceleration of chemical alteration of resist film caused by water vapor in resist film Promotion of alteration of resist film by UV irradiation

  The resist film removing apparatus of the present invention is an apparatus used in a lithography process of a semiconductor device or a liquid crystal display device, and includes: means for bringing water vapor into contact with the resist film; and means for spraying water vapor onto the resist film. The resist film is peeled off by the action.

  In one embodiment of the resist film removing apparatus of the present invention, the resist film is peeled off by saturated steam or superheated steam having a temperature of 70 ° C. to 200 ° C.

  The resist film removing apparatus of the present invention is an apparatus used in a lithography process, and includes means for injecting saturated water vapor onto the resist film, and the resist film is peeled off by the action of the saturated water vapor.

  In one aspect of the resist film removing apparatus of the present invention, the temperature at the saturated water vapor arrival site is 70 ° C to 100 ° C.

  In one embodiment of the resist film removing apparatus of the present invention, water vapor containing a resist alteration accelerating component is brought into contact with and / or sprayed onto the surface of the resist film to be peeled off.

  One aspect of the resist film removing apparatus of the present invention includes a steam generation mechanism, a steam heating mechanism, a supply water amount and heating heat amount control mechanism, and a steam pressure control mechanism, and is connected to an ultrapure water supply line. A water vapor supply device that switches and supplies saturated water vapor or superheated water vapor at 70 ° C. to 200 ° C. is provided.

  In one aspect of the resist film removal apparatus of the present invention, the water vapor supply device further includes a switching mechanism and an injection pump between the ultrapure water supply line and a solution supply line containing a resist alteration promoting component, and the resist A water vapor supply device is provided for switching between water vapor containing the alteration promoting component and water vapor not containing it.

  One aspect of the resist film removing apparatus of the present invention is provided with an ultraviolet reaction apparatus including an ultraviolet lamp having a wavelength at which a transmission distance with respect to water vapor is 10 mm or more, and the ultraviolet lamp is installed in parallel to the surface, Irradiating the substrate surface during the water vapor treatment of the resist film and irradiating the substrate surface after removing the resist film.

  In one aspect of the resist film removing apparatus of the present invention, a mechanism for introducing water vapor into a chamber having a substrate carry-in / out mechanism, an atmosphere purge mechanism, and a discharge mechanism, and the water vapor spray nozzle move relative to the substrate surface. Thus, a drive mechanism for sweeping the spray surface is provided, and the steam spray nozzle sprays steam onto the substrate surface and peels off the resist film.

  In one aspect of the resist film removing apparatus of the present invention, the chamber further includes a gas supply mechanism from a carbon dioxide gas cylinder, the carbon dioxide gas is sprayed from the gas spray nozzle onto the substrate surface, and the resist film is rapidly cooled. Strip the resist film.

  One aspect of the resist film removing apparatus of the present invention is an apparatus that further has a substrate cleaning chemical solution supply line attached to the water vapor supply apparatus, and performs cleaning by ultraviolet irradiation and water vapor jet subsequent to the resist film removal, This is an apparatus for performing subsequent drying by superheated steam injection.

  One aspect of the resist film removing apparatus of the present invention includes a filtration device or a centrifugal separator that filters the peeled resist film present in the discharged liquid, and reuses the film stripping solution that separated the peeled resist film To do.

  The resist film removal method of the present invention is a method executed in a lithography process of a semiconductor device or a liquid crystal display device, and includes a treatment of bringing saturated water vapor or superheated water vapor into contact with the resist film, and saturated water vapor or superheated water vapor to the resist film. The resist film is peeled off by the action of the water vapor.

  In one embodiment of the method for removing a resist film of the present invention, water vapor containing the resist alteration promoting component is brought into contact with the surface of the resist film to be peeled off.

  The resist film removing method of the present invention is a method that is performed in a lithography process, and performs a process of spraying saturated water vapor onto the resist film, and peels off the resist film by the action of the saturated water vapor.

  In one aspect of the resist film removal method of the present invention, the temperature at the saturated water vapor arrival site is 70 ° C to 100 ° C.

  In one embodiment of the resist film removing method of the present invention, excimer ultraviolet light having a wavelength of a transmission distance of 10 mm or more with respect to water vapor is irradiated to the substrate surface during the water vapor treatment of the resist film, and the substrate surface after resist film removal is irradiated. To do.

  One aspect of the resist film removal method of the present invention is to remove organic contamination, metal contamination, and particle contamination by spraying water vapor while continuously irradiating ultraviolet rays onto the substrate surface after removing the resist film, and then spraying water vapor. Wash and dry with

  In one embodiment of the resist film removing method of the present invention, water vapor containing a resist alteration promoting component is brought into contact with and / or sprayed onto the surface of the resist film to be peeled off.

  The resist film removing apparatus of the present invention is used in a lithography process and includes means for causing water vapor to act on the resist film, and the resist film is peeled off by the water vapor action.

  In one mode of the resist film removing apparatus of the present invention, the water vapor is saturated water vapor, and the temperature at the saturated water vapor arrival site is 70 ° C to 100 ° C.

  In one aspect of the resist film removing apparatus of the present invention, water vapor containing a resist alteration promoting component is allowed to act on the surface of the resist film to be peeled off.

  One aspect of the resist film removing apparatus of the present invention is a means for causing water to act on the resist film, a means for causing isopropyl alcohol vapor to act on the resist film, a means for causing pressurized carbon dioxide gas to act on the resist film, Means for adding a chemical component to the water vapor and / or the water; means for irradiating the resist film with ultraviolet light; means for irradiating the resist film with high frequency ultrasonic waves; and a substrate on which the resist film is formed. And at least one of the means for cooling, and by confounding at least one of the conditions among time / space conditions, temperature conditions, and physical / chemical conditions for operating each means, Strip the resist film.

  One aspect of the resist film removing apparatus of the present invention is provided with a single-wafer type chamber installed in the chamber for each substrate, and the chamber is provided with each means and the resist film is formed. A substrate loading / unloading mechanism, an atmosphere purge / discharge mechanism, a means for causing the water vapor to act on the resist film, a means for causing water to act on the resist film, and a means for causing pressurized carbon dioxide to act on the resist film And a drive mechanism for moving at least one of the means relative to the front and back surfaces of the substrate.

  In one aspect of the resist film removing apparatus of the present invention, the time / spatial conditions for operating each of the means and / or the mechanisms are the surface of the resist film, the entire front and back surfaces of the substrate, one side, For each operating part of the part, the operating sequence and the operating interval are entangled.

  In one aspect of the resist film removing apparatus of the present invention, as the temperature condition for operating each means and / or each mechanism, the surface of the resist film and the entire surface, one side, and local part of the front and back surfaces of the substrate For each operating site, the process temperature and its elevation rate are entangled.

  In one aspect of the resist film removing apparatus of the present invention, means for adding a chemical component to the water vapor and / or the water, means for irradiating the resist film with ultraviolet light, and means for irradiating the resist film with high frequency ultrasonic waves As the physical / chemical conditions for operating at least one of the above, the chemical composition of the water vapor and / or the water, the frequency of the ultrasonic wave, and the wavelength of the ultraviolet light are entangled.

  In one aspect of the resist film removing apparatus of the present invention, the temporal / spatial condition, the thermal condition, and the physical / chemical condition are entangled with each other.

  In one aspect of the resist film removing apparatus of the present invention, the means for causing the water vapor to act on the resist film has a function of bringing the water vapor into contact with the resist film and a function of spraying the water vapor onto the resist film. The contact process and the injection process are entangled.

  In one aspect of the resist film removing apparatus of the present invention, the means for causing the water vapor to act on the resist film has a function of causing the saturated water vapor to act and a function of causing the superheated steam to act. Entanglement superheated steam treatment.

  In one aspect of the resist film removing apparatus of the present invention, the steam treatment by means for causing the water vapor to act on the resist film and the chemical component blending treatment by means for adding a chemical component to the water vapor are entangled.

  In one aspect of the resist film removing apparatus of the present invention, the water vapor treatment by means for causing the water vapor to act on the resist film and the water jet treatment by means for causing water to act on the resist film are entangled.

  In one aspect of the resist film removing apparatus of the present invention, the water vapor treatment by means for causing the water vapor to act on the resist film and the ultraviolet irradiation treatment by means for irradiating the resist film with ultraviolet rays are entangled.

  In one aspect of the resist film removing apparatus of the present invention, the water vapor treatment by means for causing the water vapor to act on the resist film and the high frequency ultrasonic water irradiation treatment by means for irradiating the resist film with high frequency ultrasonic waves are entangled.

  In one aspect of the resist film removing apparatus of the present invention, the water vapor treatment by the means for causing the water vapor to act on the resist film and the pressurized carbon dioxide injection process by the means for causing the pressurized carbon dioxide gas to act on the resist film are entangled.

  In one aspect of the resist film removing apparatus of the present invention, the water vapor treatment by means for causing the water vapor to act on the resist film and the cooling treatment by means for cooling the substrate on which the resist film is formed are entangled.

  In one embodiment of the resist film removing apparatus of the present invention, the water vapor treatment by means for causing the water vapor to act on the resist film and the water vapor treatment by means for causing the isopropyl alcohol vapor to act on the resist film are entangled.

  In one aspect of the resist film removing apparatus of the present invention, a pressurized carbon dioxide jetting process by means for applying pressurized carbon dioxide gas to the resist film and an ultraviolet irradiation process by means for irradiating the resist film with ultraviolet rays are entangled. .

  In one aspect of the resist film removing apparatus of the present invention, by confounding the time / spatial condition, the temperature condition, and the physical / chemical condition for operating each means and / or each mechanism, The substrate surface after removal of the resist film is treated to remove the residue and foreign matter of the resist film and to purify the surface.

  The resist film removal method of the present invention is a technique executed in the lithography process, and performs a process of causing water vapor to act on the resist film, and peels off the resist film by the water vapor action.

  One aspect of the resist film removal method of the present invention is a process of causing water to act on the resist film, a process of causing isopropyl alcohol vapor to act on the resist film, and a process of causing pressurized carbon dioxide gas to act on the resist film, A process of adding a chemical component to the water vapor and / or the water, a process of irradiating the resist film with ultraviolet light, a process of irradiating the resist film with high frequency ultrasonic waves, and a substrate on which the resist film is formed. Among at least one of the processes to be cooled, and by confounding at least one of the conditions among time / space conditions, temperature conditions, and physical / chemical conditions for operating each process, Strip the resist film.

  In one aspect of the resist film removal method of the present invention, as the time / space conditions for operating each of the processes, the surface of the resist film, and the entire surface of the front and back surfaces of the substrate, one surface, and each operation site of a local site Entangle the operating sequence and interval.

  In one aspect of the resist film removal method of the present invention, as the temperature condition for operating each of the processes, the surface of the resist film, and the entire surface of the front and back surfaces of the substrate, one surface, and each operation site of a local site are processed. The temperature and its elevation speed are entangled.

  One aspect of the resist film removal method of the present invention is a process of adding a chemical component to the water vapor and / or the water, a process of irradiating the resist film with ultraviolet light, and a process of irradiating the resist film with high frequency ultrasonic waves. As the physical / chemical conditions for operating at least one of the above, the chemical composition of the water vapor and / or the water, the frequency of the ultrasonic wave, and the wavelength of the ultraviolet light are entangled.

  In one aspect of the resist film removal method of the present invention, the temporal / spatial condition, the thermal condition, and the physical / chemical condition are entangled with each other.

  In one aspect of the resist film removal method of the present invention, the treatment of causing the water vapor to act on the resist film includes a step of bringing the water vapor into contact with the resist film and a step of spraying the water vapor onto the resist film. The contact process and the injection process are entangled.

  In one aspect of the resist film removing method of the present invention, the treatment of causing the water vapor to act on the resist film includes a step of causing saturated water vapor to act and a step of causing superheated steam to act. Entanglement the superheated steam process.

  In one aspect of the resist film removing method of the present invention, the water vapor process by the process of allowing the water vapor to act on the resist film and the chemical component blending process by the process of adding a chemical component to the water vapor are entangled.

  In one embodiment of the resist film removing method of the present invention, a water vapor process by a process of causing the water vapor to act on the resist film and a water jet process by a process of causing the water to act on the resist film are entangled.

  In one aspect of the resist film removing method of the present invention, a water vapor process by a process of causing the water vapor to act on the resist film and an ultraviolet irradiation process by a process of irradiating the resist film with ultraviolet light are entangled.

  In one aspect of the resist film removing method of the present invention, the water vapor process by the process of causing the water vapor to act on the resist film and the high frequency ultrasonic wave superposed water irradiation process by the process of irradiating the resist film with high frequency ultrasonic waves are entangled.

  In one aspect of the resist film removing method of the present invention, the water vapor process by the process of causing the water vapor to act on the resist film and the pressurized carbon dioxide injection process by the process of causing the carbon dioxide gas to act on the resist film are entangled.

  In one embodiment of the resist film removing method of the present invention, a water vapor process by a process of allowing the water vapor to act on the resist film and a cooling process by a process of cooling the substrate on which the resist film is formed are entangled.

  In one embodiment of the resist film removing method of the present invention, the water vapor process by the process of causing the water vapor to act on the resist film and the water vapor process by the process of causing the isopropyl alcohol vapor to act on the resist film are entangled.

  In one aspect of the resist film removing method of the present invention, a pressurized carbon dioxide spraying process by a process of applying a pressurized carbon dioxide gas to the resist film and an ultraviolet irradiation process by a process of irradiating the resist film with ultraviolet rays are entangled. .

  In one aspect of the resist film removal method of the present invention, the temporal / spatial conditions for operating each of the processes, the thermal conditions, and the physical / chemical conditions are entangled so that the resist film is removed after the resist film is removed. The substrate surface is treated to remove the residue and foreign matter of the resist film, and clean the surface.

  According to the present invention, the resist film can be easily and reliably peeled off by utilizing the physical property change (swellability, etc.) of the resist due to water vapor and the photodecomposition effect by ultraviolet rays. It is possible to realize an environmentally symbiotic technology that does not depend on energy or a chemical solvent for removing the resist, that is, removing the resist.

It is a schematic diagram which shows the injection nozzle vicinity of the resist removal apparatus of this invention. FIG. 6 is a characteristic diagram showing the relationship between the KOH concentration and the removal rate in resist removal using water vapor containing KOH. It is a schematic diagram which shows the main structures of the water vapor | steam supply apparatus of one Embodiment of this invention. It is a schematic diagram which shows the main structures of the resist removal apparatus of one Embodiment of this invention. It is a schematic sectional drawing which shows the mode of each sample which peels a resist film. It is a schematic sectional drawing which shows the single wafer type resist removal apparatus with a spin rotation mechanism.

  Hereinafter, preferred embodiments to which the present invention is applied will be described.

1. Resist stripping with water vapor Porosity and hydrogen bonding of resist chemical structure:
In the lithography process, in order to form a fine structure of a semiconductor integrated circuit, a resist film is adhered to a processing surface, and electromagnetic wave energy is irradiated through a fine structure pattern gap formed on a mask, so that an irradiation portion and a non-irradiation portion are This is a process of developing a pattern by utilizing the difference in resist solubility and performing pattern etching.

  In photolithography, with the progress of the generation of integration, g-line, i-line, ArF to F2 excimer laser and gradually shorter wavelength ultraviolet rays are used. Naturally, the chemical structure of the resist will be reformed with shorter wavelengths and will be further reformed for the future X-ray and electron beam lithography era. The important thing is to determine the physical properties of the fundamental structure that is basically unchanged as the chemical structure of the resist is reformed.

The inventors pay attention to the porosity and hydrogen bonding property of the base polymer backbone structure of the resist.
Table 1 shows base polymer basic structures of various photoresists such as the initial resist KPR, the current mainstream resist, and the ARF excimer resist. The chemical structures of the main and side chains are completely different. However, there is a basic commonality between these various basic structures.

  It is the porosity of the backbone structure and the hydrogen bonding properties of the constituent groups. The polymer backbone structure has a large gap due to the structure having a cyclic structure and side chains such as alicyclic groups and phenol groups.

  In addition, constituent groups having strong hydrogen bonding properties, such as phenol groups, carbonyl groups, ester groups, and the like, have been introduced. The introduction of these groups is necessary for the resist to be sensitive to light energy. In addition, since the resist must have solubility in the developer, the porosity and hydrogen bonding properties are physical properties necessary for dissolution.

Further, the water permeability of the resist is larger than that of other organic polymers. For example, Teflon (registered trademark) and polyethylene have a water permeability (Pa · cm ² · s ⁻¹ · m ⁻² ) of about 3 × 10 ⁻¹¹ , but from the base polymer backbone structure of the resist (see Table 1). In view of this, the water permeability of the resist is considered to be greater.
This is because the polymer structure of the resist is vacant and has hydrogen bonding properties, compared to the denseness of the structurally ordered organic polymer.

In the future, resists will be required to be chemically amplified, and chemical amplification components will be added.
However, it is the base polymer backbone structure that dominates “resist stripping”. The feature of the present invention resides in the use of the vacancy and hydrogen bonding, which are the basic physical properties of the resist.

Alteration of resist film by water vapor:
The inventors pay attention to the fact that the state of the resist film is rapidly and significantly changed by water vapor. Physical changes such as softening / expansion due to high-temperature steam naturally occur, and physical properties such as swelling / separation / solidification occur, and the appearance varies depending on the type of resist and water vapor conditions. It can be seen that the mechanical alteration has occurred. The contents of this alteration are estimated as follows.

  As described above, since the basic structure of the resist base polymer has porosity, the resist permeability of water vapor is extremely large. The resist film in contact with the water vapor is instantaneously charged into the high temperature chemical reaction system. It is well known that the chemical action of hot water is strong, and there are many examples of hydrolysis of organic compounds by hot water. In the resist chemical structure, there are side chains and photosensitive groups with high hydrogen bonding properties. In addition to hydrolysis and oxidation of these groups, the crosslinking of the resist backbone structure proceeds.

Action of saturated or superheated steam:
The water vapor temperature required for processing the resist film varies depending on the type of resist and the resist process conditions. The water vapor temperature is selected to be a suitable value between 70 ° C and 200 ° C. It may be 200 ° C. or higher if the conditions of the substrate allow. Superheated steam does not absorb or scatter ultraviolet rays due to mist, and has high ultraviolet transmission efficiency. Further, the superheated steam is not affected by mist in drying the resist film peeling surface.

Peeling of swollen resist film and substrate by water vapor jet:
The spray force of water vapor effectively acts on the peeling of the swelling resist film and the substrate. Resist films that are hydrated, swollen, and softened by high-temperature water vapor and mist, as well as swelling-promoting components, are easily peeled off from the substrate surface at a linear velocity of water vapor jet of several meters / second to several tens of meters / second. The stripping speed depends on the type of resist, but in particular, a resist implanted with ions tends to be difficult to strip. The pattern shape is also related, and when the aspect ratio is large, it tends to be difficult to peel off. In consideration of such resist physical properties and substrate structure, the linear velocity and time of jetting are controlled. As the resist is peeled off, it is important to suppress the jet linear velocity so as not to damage the fine structure of the exposed surface.

Steam contact and spray:
There is a need for an apparatus that can combine the step of bringing a resist film into contact with water vapor and altering it, and the step of spraying and peeling off the water vapor on the altered resist film.

  The surface structure exposed by resist stripping must be protected without any damage. The spraying force of water vapor with a linear velocity of 1 m / second to several tens of m / second is strong and effective for resist stripping, but may damage the device surface. A two-step process is effective, in which the resist film is advanced in the contact step and then peeled off in a short injection step. In particular, it is suitable for removing an ion-implanted resist film having a slow alteration rate and removing a resist film on a surface having a large structure aspect ratio.

Resist stripping only by spraying saturated water vapor:
The inventors of the present invention have conceived that the resist film is peeled off only by spraying water vapor containing droplets, that is, saturated water vapor, without passing through the two stages of contact and spray of water vapor as described above.

Specifically, as shown in FIG. 1, for example, when the resist film 44 is removed after patterning the SiO ₂ film 43 on the substrate 42, the water vapor spray nozzle 41 is opposed to the resist film 44 to spray water vapor. Then, the resist film 44 is peeled off. At this time, as a spraying condition, the temperature of saturated water vapor at the water vapor arrival site, that is, the surface region of the resist film 44 is set to 70 ° C. to 100 ° C., preferably 75 ° C. to 85 ° C. This is because if the temperature is adjusted to the temperature range, the sprayed water vapor becomes droplet-containing saturated water vapor suitable for resist stripping at the surface portion of the resist film 44. In the illustrated example, as an example of the temperature range, the distance from the spray nozzle 41 to the surface of the resist film 44 is 10 mm. Further, the steam injection pressure at the distal end portion of the injection nozzle 41 is less than 10 kg / cm ^2, preferably made to be 1-2 kg / cm ^2. This is because if the pressure exceeds 10 kg / cm ² , the device member formed on the injection nozzle 41 or the substrate 42 may be adversely affected.

  The treatment using the resist alteration promoting component-containing water vapor described in the next section for the contact step and pure water vapor for the spraying step is effective for preventing damage to the surface of the metal wiring.

Resist alteration promoting component:
It was recognized that the physical and structural alteration due to high-temperature steam can be accelerated by containing a component that promotes alteration in the steam. In particular, a resist film cured by an ion implantation treatment process is extremely difficult to peel off, but if an accelerating component is contained in the water vapor, rapid peeling is possible. The content of the accelerating component varies depending on the type of resist and must be selected individually. Further, it is necessary to consider the protection of the structure substrate after the resist is peeled off, for example, the chemical action on the metal surface of the metal wiring substrate.

  The oxidizing substance is effective as a component for promoting crosslinking or oxidation. For example, hydrogen peroxide alters and removes an ion-implanted resist film in a short time. This is thought to be due to the oxidation of the chemical bond of the resist by a strong radical reaction. Ozone water is also effective as an oxidation promoting component.

As other oxidizing substances, Cl ₂ —H ₂ O, Br ₂ —H ₂ O, I ₂ —KI, NaClO, NaClO ₄ , KMnO ₄ , K ₂ CrO ₇ , Ce (SO ₄ ) _{2 and the} like are selected. .

Alkali is a powerful accelerating component. For example, a caustic aqueous solution having a pH value of about 8 to 14, preferably 10 to 12, is used. The resist surface has wettability and permeability, and the removal action is quick. As the alkali, KOH, NaOH, NaCO ₃ , Ca (OH) ₂ , Ba (OH) ₂ , NH ₄ OH, TMAH, or the like can be used.

  Specifically, the removal rate when removing the resist film used as a mask when ion implantation of impurities (As) was performed by the method shown in FIG. 1 using alkali KOH as a resist alteration promoting component. The measurement results are shown in FIG. Here, the horizontal axis represents the concentration (% by weight) of KOH, and the vertical axis represents the removal rate (seconds). Thus, it can be seen that the higher the KOH concentration, the faster the removal speed and the more efficient resist removal is realized. However, if the KOH concentration exceeds a certain value, there is a concern about an adverse effect on the device material. Therefore, it is considered that about 0.1 (% by weight) or less is appropriate.

Acids and oxidizing acids are also components that promote alteration. For example, H ₂ SO ₄ strongly crosslinks the resist. H ₂ SO ₄ , HNO ₃ , HClO, HClO ₄ , HCl, HF and the like can be used.

  The surfactant has an interfacial penetrating action and at the same time has a surface action that prevents the removed resist flakes from reattaching to the surface. As the surfactant, an anion, cation, or nonionic surfactant having a contact angle with respect to the resist surface of 30 degrees or less, preferably 20 degrees or less is selected.

2. Removal of resist by ultraviolet rays (1) Decomposition of resist by ultraviolet rays Table 2 shows the decomposition test data of photoresists by ultraviolet rays. Photoresist photolysis can be performed using a Xe excimer lamp (wavelength 172 nm) as an ultraviolet lamp. However, the decomposition rate is low when applied to the process of removing the resist. Although there is an attempt to accelerate by making ozone present at a high concentration, there are many difficulties in practical use.

  The inventors pay attention to the alteration of resist due to ultraviolet rays. Intended to remove resist, not resist decomposition. Since ultraviolet photons have a strong crosslinking or oxidation promoting action, the resist altering action is strong. The superimposing effect with the alteration action of water vapor is used. Further, since ultraviolet rays have high resist permeability, they reach the resist / substrate boundary layer sufficiently. It is a powerful osmotic action. The alteration of the boundary layer directly leads to a peeling effect.

3. Steam Supply Device FIG. 3 illustrates a principle diagram of the steam supply device. An evaporator 1 and an evaporation heating block 2 for generating saturated steam, and a superheater 3 and an overheating heating block 4 for generating superheated steam are disposed between the constant flow pump 5 and the pressure control needle valve 6. The internal pressure of this water vapor generation system is measured by a pressure gauge 7. The saturated steam temperature and the superheated steam temperature are measured by thermometers 8 and 9. The heat transfer area of the evaporator 1 is designed so as to satisfy the burnout point condition of the boiling characteristic curve.

Switching between pure water vapor and water vapor containing promoting components:
When the vapor of ultrapure water is generated, the valve 10 for the ultrapure water line is opened, and when the vapor containing the accelerating component is generated, the valve 11 for the aqueous solution line is opened.

Switching between saturated and superheated steam:
At the time of supplying saturated steam, heat is not supplied to the heating block 4 for superheating, and at this time, the superheater 3 simply serves as a steam passage. At the time of superheated steam supply, the amount of heat is supplied to the superheater heating block 4 and is heated by the superheater 3.

Switching between water vapor contact and water vapor injection:
When water vapor is introduced into the processing chamber 15, the introduction valve 12 is opened. In the case of injecting water vapor onto the treatment surface, the water vapor injection valve 13 is opened and water vapor is injected from the water vapor injection nozzle 14 onto the treatment surface 16.

  Table 3 exemplifies the control conditions for water vapor supply. Table 4 exemplifies the conditions of the water vapor injection nozzle. The nozzle shape, water vapor amount, and jetting speed are arbitrarily designed to suit the purpose.

4). Ultraviolet reactor The selection of the ultraviolet wavelength and time characteristics of a lamp used in an ultraviolet reactor is an important technical element.

Selection of UV wavelength:
The shorter the wavelength of ultraviolet rays, the larger the energy and the lower the transmittance of the irradiation atmosphere. The ultraviolet wavelength must be selected to satisfy the transmittance.

The relationship between the light absorption cross section of the molecules present in the atmosphere and the light transmittance is given by equation (1). The logarithm of the transmittance and the distance are in a proportional relationship. The inventors use 50% transmission distance as an index. This 50% transmission distance is given by equation (2). Table 5 shows the relationship between the ultraviolet wavelength and the 50% transmission distance of air, water, and water vapor obtained by equation (2) or by actual measurement. For example, the 50% transmission distance of ultraviolet light with a wavelength of 172 nm is obtained as 3.1 mm from the light absorption cross section of oxygen (0.259 × 10 ⁻¹⁹ molecules / cm ² ), while the measured value is 2.2 mm. And almost match.

δCL = ln (I ⁰ / I) (1)
δ: light absorption cross section (number of molecules / cm ² ), O ₂ ... 0.259 × 10 ⁻¹⁹
C: Molecular concentration (molecular partial pressure)
L: Transmission distance (cm)
I ⁰ / I: Light transmittance = incident light intensity / transmitted light intensity (2)
δCL ₅₀ = ln (100/50)
L ₅₀ : 50% transmission distance

Selection of time response:
The ultraviolet lamp is selected depending on whether the ultraviolet treatment is performed in an instantaneous type or a stationary type.
Ultraviolet excimer lamps can be used for instantaneous processing. Lights up and reaches steady state in a few seconds.
Suitable for sequential process of unit time per second in single wafer type UV treatment. Low-pressure mercury lamps, i-line lamps, etc. can be used for stationary processing. It takes several tens of minutes to turn on and reach a steady state, but it is stable thereafter.

5. Single-wafer resist stripping apparatus (1) Device configuration The single-wafer resist stripping apparatus includes a steam treatment chamber and an ultraviolet lamp chamber.
A chamber with a substrate carry-in / out mechanism, atmospheric purge mechanism, and drainage mechanism has a drive mechanism that sweeps the ejection surface by moving the substrate surface and water vapor ejection nozzle relative to each other. Arranged and configured.

  FIG. 4 illustrates a single wafer resist stripping apparatus having a spin rotation mechanism. This apparatus includes a steam treatment chamber 23 having a spin rotation mechanism 22 for rotating a substrate 21, and a lamp chamber 26 that houses an ultraviolet lamp 24 and has a quartz window plate 25. A gas inlet 27 to the chamber and a discharge duct 28 are attached.

  When water vapor is introduced into the processing chamber from the water vapor supply device 31 (the device shown in FIG. 3), the water vapor introduction valve 12 is opened. When injecting water vapor onto the processing surface, the water vapor injection valve 13 is opened and water vapor is injected from the water vapor injection nozzle 14 onto the processing surface of the substrate 21.

The steam spray nozzle 14 shows the case where the line slit nozzle is arranged in the diameter direction.
The spot nozzle may be driven in the radial direction, or several nozzles may be moved or fixed at an appropriate distance. The spray angle and spray distance of the nozzle and the water vapor spray line distance are optimized from various aspects such as processing purpose, substrate surface structure, and damage protection.

  The steam treatment chamber 23 is kept warm. Water vapor condenses little by little on the inner wall of the chamber and serves to clean the inner wall. In this way, the inside of the chamber is always kept clean.

  The gas inlet 27 to the chamber is used for replacing the chamber atmosphere when the substrate is carried in and out. It is also used for the purpose of adding components effective for treatment to the atmosphere. The discharge duct 28 preferably has a cooling structure.

(2) Physical peeling acceleration Resist film quenching (rapid cooling):
Although omitted in FIG. 4, a carbon dioxide gas injection nozzle is disposed on the substrate surface, carbon dioxide gas is injected, dry ice particles are injected onto the substrate surface, and the resist film can be quenched (rapidly cooled). The heated and swollen resist film shrinks and solidifies and peels from the substrate. Depending on the type of resist, it is recognized that such quenching promotes stripping.

High speed spin rotation:
Peeling is promoted when the rotation speed is set to 2000 rpm or more using a spin rotation mechanism. In particular, peeling is promoted when the water vapor injection effect is weak at the periphery.

6). Continuation of resist stripping process and post-stripping surface cleaning process The resist stripping process and post-resist stripping surface cleaning process can be made continuous.
Switching from the resist film peeling apparatus to the surface purification apparatus after the resist film peeling is simple.

By further using the aqueous solution line 11 of the water vapor supply device of FIG. 3 as a switching system between the peeling accelerating solution line 11A and the surface cleaning solution line 11B, the resist stripping device and the post-resist stripping surface cleaning device can be arbitrarily switched.
Since the water vapor / ultraviolet ray superimposing process effectively shortens both the peeling time and the purification time, integration can be realized without reducing the throughput.

  Hereinafter, specific embodiments of the invention will be described with reference to various examples. Although the description is omitted in each example, the resist peeling state is based on observation of the peeling surface for each spraying time with an optical microscope.

Example 1
An example of resist film peeling with pure water vapor will be shown.
Sample: FIG. 5A: Resist film formed on dry etching thermal oxide film FIG. 5B: Resist film formed on dry etching gate electrode (polysilicon film) Water vapor: Pure water vapor Stripping results:
Table 6, peeling was possible in 30 seconds to 1 minute.

(Example 2)
An example of resist film peeling with water vapor containing an accelerating component is shown.
It is known that the resist film has been ion-implanted and is extremely difficult to remove.

Sample: FIG. 5 (c) Silicon thermal oxide film etching, ion implantation into lower layer silicon substrate Ion implantation conditions: acceleration energy 80 KeV, phosphorus dose 6 × 10 ¹⁵ / ccm ²
Accelerating component-containing water vapor: Accelerating component, alkali (KOH) and surfactant
As shown in Table 7, it was able to be peeled off in 2 minutes by steam injection. In the case where the alteration promoting component is an alkali, there was a slight amount of peeled fragments adhering to the surface after peeling, but in the case of alkali + surfactant, no peeled fragments were observed.

(Example 3)
An example of resist film peeling with water vapor containing an accelerating component is further shown.

Sample: FIG. 5 (d) Silicon thermal oxide film wet etching, negative resist film FIG. 5 (e) Positive resist film after metal wiring etching Promoting component-containing water vapor: Promoting component, hydrogen peroxide and surfactant Peeling results:
The water vapor jet containing the alteration promoting component completely peeled off from the surface of the thermal oxide film in 1 minute, and the metal wiring etching-ion implantation surface inferior in peelability peeled off completely in 2 minutes.

Example 4
An example of a two-step water vapor treatment on the surface of a metal wiring is shown.
The purpose of the two-step process is to avoid chemical damage to the metal wiring. When the resist covers the metal wiring surface, the accelerating component is used. When the resist is peeled and the metal wiring surface is exposed, the accelerating component is not used.

Details of the two-step process:
First step (steam contact treatment) using alkali-containing water vapor Second step (steam injection treatment) using pure water steam Peeling results:
Table 9 shows. In the second step, the resist was removed by the water vapor treatment for 30 seconds, and there was no metal wiring damage.
As a comparison, the case of only alkali-containing steam treatment is shown. In this case, a spraying time of 2 minutes is required, and damage was observed on the metal wiring on the surface after resist removal.

(Example 5)
An example of high-temperature steam treatment is shown for an ion-implanted resist film that is difficult to peel off.
Sample: FIG. 5 (c) Silicon thermal oxide film etching, ion implantation into lower layer silicon substrate Ion implantation conditions: acceleration energy 80 KeV, phosphorus dose 6 × 10 ¹³ / cm ²
Table 10 shows the peeling results.
The condition 1 100 ° C. saturated steam treatment cannot be removed even after 10 minutes of injection.
In the condition 2 of 120 ° C. saturated water vapor treatment, the contact treatment was performed for 2 minutes and the injection treatment was performed for 1 minute.
After 30 seconds of 130 ° C. saturated steam treatment of condition 3, 140 ° C. superheated steam treatment was able to be removed in 30 seconds of jetting treatment.
An alteration effect due to high-temperature saturated steam and a peeling effect due to high-temperature superheated steam are recognized.

(Example 6)
An example of water vapor / ultraviolet ray superimposition treatment is shown for an ion-implanted resist film that is difficult to peel off.
UV lamp: KrI excimer lamp, wavelength 191nm
UV irradiation amount: 10 mW / cm ² (treated surface)
The peel results are shown in Table 11. After 2 minutes of 100 ° C. saturated steam treatment and ultraviolet irradiation treatment of Condition 1, the spraying treatment could be removed in 1 minute.
After the condition 2 of 120 ° C. saturated steam treatment and ultraviolet irradiation treatment for 30 seconds, the jetting treatment was completed in 30 seconds.

(Example 7)
An example of continuation of the resist stripping process and the post-stripping surface cleaning process will be described.
UV lamp: KrI excimer lamp, wavelength 191nm
UV irradiation amount: 10 mW / cm ² (treated surface)

Resist stripping step:
Using saturated water vapor at a temperature suitable for various resist processes, resist peeling is performed by first step water vapor contact and second step water vapor jet while superimposing ultraviolet irradiation.

Cleaning step:
Each chemical solution is sequentially supplied from the cleaning solution supply line to generate chemical solution-containing water vapor. First, saturated water vapor containing hydrofluoric acid and hydrogen peroxide is sprayed onto the substrate surface to remove metals and organic substances. At this time, particles are removed by the spraying force of the water vapor mist. Next, dilute hydrofluoric acid-containing saturated water vapor is sprayed onto the substrate surface. For example, the silicon surface of the substrate surface contact hole is a barrier silicon. Finally, pure water vapor is jetted and washed. This chemical prescription is arbitrarily selected according to the purpose of processing.

Drying step:
Since superheated steam does not contain mist, it can be quickly dried. Superimposition of UV irradiation achieves a surface cleansing finish with accelerated drying.

Peeling result:
Both resist removal and surface cleaning were completely achieved.

-Examples in which the present invention is viewed from other viewpoints-
As described above, the present inventors have realized a technique for stripping a resist film using water vapor, and established a technique for superimposing a chemical component promoting effect and an ultraviolet irradiation effect on this.

  In parallel with this, the present inventors have further entangled the application of the peeling action, specifically the operation of the peeling mechanism, with respect to time / space conditions, temperature conditions and physicochemical conditions. Presenting technology to ensure reliable and rapid peeling. That is, it is possible to grasp the resist film peeling technique from a new viewpoint of considering each of the entanglement modes, and to make the technique more concrete and realistic.

1. Confounding of processing conditions In general, processing conditions are often set constantly. However, the film peeling phenomenon is a steady state failure phenomenon called adhesion. Thus, exfoliation is essentially an unsteady phenomenon. For example, the resist film swells and hydrates due to the action of water vapor, but does not reach the peeling phenomenon if the physicochemical action continues. The physical action of injection must change. As described above, various conditions need to be mixed in a non-stationary manner in the peeling process.

  Confounding is not just an intersection of different conditions. Confounding refers to conditional arrangement that presupposes the prediction and grasping of means and results. The contents include interrupt condition design, reverse condition design, and variable condition design. This is a technique for producing an effect by confounding such processing conditions.

  In particular, the greatest reason why the processing conditions need to be entangled in the resist film stripping technique is that there is a sanctuary that the protection of the microstructure on the stripped exposed surface must be ensured. In the peeling process, the resist film surface and the fine structure surface coexist temporarily. On the one hand, the conditions effective for peeling are the damage conditions for the microstructured surface. In order to achieve both peeling and microstructural surface protection, entanglement of processing conditions is necessary.

2. Specific Aspects of Entangling Process Conditions (1) Aspects of Temporal / Spatial Entanglement Aspects of entanglement in time are, for example, the order in which the two conditions A and B are activated, such as the order of A → B or A ← B order or AB at the same time, set the operation time to A and B respectively.
The spatially entangled aspect is, for example, a case where the processing surface is the entire surface, a single surface, or a partial surface.

(2) Aspects of thermal entanglement The part that operates the heating / cooling mechanism is the entire surface, one surface, or partial surface of the treated surface. For example, they are combined such as single-sided heating and single-sided cooling. Set preheating or rapid heating, precooling or rapid cooling. That is, there is also an aspect in which the application of temperature is entangled in time / space.

(3) Aspects of physicochemical confounding This is an aspect of composition / concentration combination of chemical components and temporal / spatial confounding of chemical component application. This is a mode in which high-frequency ultrasonic / ultraviolet irradiation is combined.
As described above, the above (1), (2), and (3) can also be entangled.

3. Specific contents of confounding of processing conditions Hereinafter, the specific contents of confounding are exemplified. Conditional confounding is not limited to this example.

(1) Entanglement of steam contact and steam injection (temporal confounding)
It takes time for the resist film to swell and hydrate due to the chemical action of water vapor. This process is preferably a static contact treatment with water vapor. At the time when the resist film is altered by water vapor, a water vapor injection force is required. That is, it is necessary to combine the water vapor contact process and the water vapor injection process with a time interval.
This specific example is Example 4 described above, and can be regarded as a confounding of water vapor contact, injection, and alkali.

(2) Entanglement of saturated steam treatment and superheated steam treatment (temporal, temperature, physicochemical confounding)
Saturated steam provides wet conditions and superheated steam provides high temperature drying conditions. For example, a 100 ° C. saturated steam treatment process and a 100 ° C. saturation to 150 ° C. superheated steam treatment process are entangled. In the 100 ° C. saturated steam treatment process, the swelling and hydration of the resist film proceeds. In the process of 100 ° C. saturation to 150 ° C. superheated steam treatment, the adhesion boundary of the resist film is dried, and this acts as boundary peeling force. Therefore, it is effective to combine the 100 ° C. saturated steam treatment process and the 100 ° C. saturation to 150 ° C. superheated steam treatment process at appropriate time intervals.
Further, the superheated steam treatment process is effective for use in the drying process after the peeling-cleaning process is completed.
This specific example is Example 5 described above, and can be regarded as a confounding of saturated steam and superheated steam.

(3) Entanglement of steam treatment and chemical component-containing steam treatment (physicochemical and temporal condition confounding)
The fact that the alteration of the resist film is promoted by the chemical component-containing water vapor has already been clarified. For example, water vapor added with an alkali component quickly peels off the resist film. However, when the fine structure is, for example, a metal wiring surface, wiring materials such as aluminum and copper (particularly aluminum) are etched and damaged by alkali. In this case, the chemical damage of aluminum can be reduced to an extent that does not become a daily problem by using water vapor containing a certain type of surfactant. Specific examples of this are the above-described Examples 2 and 3, which can be regarded as an entanglement of alkali and hydrogen peroxide.

(4) Entanglement of steam treatment and isopropyl alcohol (IPA) steam treatment The resist stripping effect of an IPA-water-salt stripping solution is known. The gas-liquid interface action of IPA is famous as the Marangoni effect. The inventors have found that IPA vapor has a resist peeling accelerating effect in a water vapor atmosphere. Since IPA is an organic chemical component that does not act on the surface material at all, it can be used without damaging the surface of the metal wiring.
Confounding mode 1: (temporal / physicochemical condition confounding)
The steam treatment and the IPA steam treatment are entangled in time.
Confounding mode 2: (physicochemical condition confounding)
IPA steam treatment, that is, entangle the composition of chemical components.

(Example 8)
For each type of resist film, the confounding effect of the IPA vapor treatment in the water vapor treatment was investigated.
Resist film peeling was achieved in 1 to 2 minutes under the entanglement treatment conditions shown in Table 13 below.

(5) Entanglement of water vapor treatment, water jet treatment, and superposition of high-frequency ultrasonic waves There are a resist film that can be sufficiently peeled off by a water vapor jet force after the water vapor treatment, and a resist film that requires time for peeling with the water vapor jet force. In the latter case, confounding of the water injection process is effective. At the same injection amount, the impact force of water is greater than water vapor in proportion to the mass difference of about three orders of magnitude. In addition, the resist softened at the water vapor temperature works to be peeled off by cooling and hardening with water jet.

  High pressure pressurized water, ie jet water flow, is used for cutting silicon wafers and surgical scalpels. Pressurized water jets can peel any strong film, while maintaining sufficient damage protection conditions on the micromachined surface. Therefore, the linear velocity design of the water injection is important for relaxing the pressure / injection amount condition, that is, for protecting the fine structure.

Confounding mode 1: (temperature / physicochemical condition confounding)
After the steam contact treatment, the water injection treatment is performed at a relaxed pressure. The confounding effect of the high temperature chemical action of water vapor and the cooling action of pressurized water is obtained.

Confounding mode 2: (Temperature and spatial condition confounding)
Water vapor jet processing is performed on one side of the spin rotation surface, and water jet processing is performed on the other side. The surface is given a temperature amplitude of heating and cooling in a cycle of the number of rotations. Even in this entanglement mode, the peeling action similar to the above works.

Entanglement mode 3: (physicochemical condition entanglement)
In either of the entanglement modes 1 and 2, water jetting is performed using a high-frequency ultrasonic nozzle. Since the injection force and the ultrasonic force are superimposed and the peeling force is large, it is carried out under the condition that each strength is relaxed in order to maintain the fine circuit structure.

Example 9
For each type of resist film, the confounding effect of water jet treatment and high-frequency ultrasonic superposition was investigated. Resist film peeling was achieved in 1 to 2 minutes under the confounding treatment conditions shown in Table 14 below.

(6) Entanglement of steam treatment and pressurized carbon dioxide injection process This entanglement effect has a special effect in addition to the cooling hardening effect similar to the entanglement of water injection process.
The temperature of the dry ice fine particles generated by the pressurized carbon dioxide gas injection is minus 55 ° C. Moisture permeating the adhesion boundary of the resist film by the water vapor treatment is instantly crystallized and expanded by carbon dioxide gas injection. That is, a frost column effect is generated by freezing of moisture, and it works as a strong peeling force.

Entanglement mode 1: (Temperature, time, physicochemical conditions)
When the steam treatment and the pressurized carbon dioxide injection treatment are repeated alternately and occasionally, the peeling action due to the temperature amplitude of heating and cooling works. This is because the expansion coefficient differs depending on the substance. For example, the linear expansion coefficient is 0.076 × 10 ⁻⁴ / k for silicon, and 2.2 to 5.0 × 10 ⁻⁴ / k for most organic materials, which is about 1 to 2 orders of magnitude different. The difference in linear expansion coefficient between the silicon substrate and the resist film becomes the boundary layer peeling force with a temperature amplitude of about 150 ° C.

Confounding mode 2: (Temperature, spatial, physicochemical condition confounding)
When performing the water vapor injection process on one side of the spin rotation surface and the pressurized carbon dioxide injection process on the other side, the surface is given a temperature amplitude of heating / cooling in a cycle of the number of rotations. Even in this entanglement mode, the peeling action similar to the above works.

Confounding mode 3: (Temperature, spatial, physicochemical condition confounding)
When performing the water vapor jet process on the spin-rotating resist surface side and the pressurized carbon dioxide gas jet process on the back surface side, a temperature difference is given to the boundary surface between the resist surface and the substrate. Even in this entanglement mode, the peeling action similar to the above works.

(Example 10)
For each type of resist film, the confounding effect of the pressurized carbon dioxide jet treatment on the steam treatment was investigated. Resist removal could be achieved in 1 to 2 minutes under the confounding treatment conditions shown in Table 15 below.

(7) Entanglement of steam treatment and substrate cooling treatment (temperature condition entanglement)
The resist surface is subjected to water vapor treatment while supporting the treatment substrate with a cooling plate. The cooling plate may be cooled by any method such as an electronic cooling method using a Peltier element, a fluorine oil refrigerant circulation cooling method, and a pressurized carbon dioxide jet ventilation cooling method.
The confounding effect and peeling action are the same as the cooling action of water injection and high pressure carbon dioxide injection.

(Example 11)
For each type of resist film, the substrate cooling effect in the water vapor treatment was investigated. Since the entanglement order and the entanglement time of the water vapor spraying step and the substrate cooling step differ depending on the type of resist, a condition having a large effect is selected. The confounding treatment conditions shown in Table 16 below are an example, and the resist removal could be achieved in 1 minute to 2 minutes.

(8) Confounding of steam treatment and ultraviolet irradiation treatment (physicochemical confounding)
In the case of superimposing on the water vapor treatment, ultraviolet rays having a water vapor 50% transmission distance of 2 mm or more are used. It is efficient to superimpose on the superheated steam treatment. Since superheated steam does not contain mist, there is no ultraviolet light scattering loss. It is sufficient that the amount of ultraviolet light and the irradiation time are sufficient to cause alteration by photochemical action on the resist adhesion surface.
A specific example of this is Example 6 described above, which can be regarded as a confounding of water vapor and ultraviolet rays.

(9) Entanglement of high-pressure carbon dioxide treatment and UV irradiation treatment (physicochemical confounding)
In a carbon dioxide atmosphere, ultraviolet rays having a short wavelength with a 50% water vapor transmission distance of 2 mm or less can be used with a high transmittance. The transmission distance of 50% carbon dioxide gas for ultraviolet rays having a wavelength of 172 mm is about 30 cm. A xenon excimer lamp (172 mm) can be applied. This is effective for decomposing and removing fine resist fragments that are not removed in the fine structure gap after the resist film is peeled off.

(Example 12)
In the case where fine resist film pieces remain at the corners of the pattern after the resist peeling process on the surface of the device having the fine structure pattern or the gap between the wirings, the residual film pieces were decomposed and removed by the ultraviolet irradiation process.
A xenon excimer lamp was irradiated while injecting carbon dioxide onto the surface. The results are shown in Table 17 below.

(10) Entanglement with cleaning treatment The surface clean level after resist stripping and the surface clean level required in the next step vary from process to process. Therefore, there is a need for an easy mechanism that can entangle the water vapor conditions and ultraviolet entanglement used in the cleaning process after resist stripping.
This specific example is Example 6 described above, and can be understood as a confounding with the cleaning process.

3. Here, a specific example of the resist removing apparatus in consideration of the entanglement mode of various processes (means) will be described.
FIG. 6 is a schematic sectional view showing a single wafer resist removing apparatus having a spin rotation mechanism.

  This resist film removing apparatus includes a mechanism that introduces IPA vapor, water, and pressurized carbon dioxide gas into a chamber having a substrate carry-in / out mechanism, an atmosphere purge mechanism, and a discharge mechanism, in addition to a mechanism that introduces water vapor, Equipped with at least one of a mechanism for adding chemical components to water, a mechanism for irradiating ultraviolet and high-frequency ultrasonic waves, and a mechanism for heating and cooling the substrate. Thus, a drive mechanism for sweeping the ejection surface is provided.

  A spin rotation mechanism is provided inside the steam treatment chamber 101. The spin rotation mechanism includes a rotating body 104 having a support pin 103 for fixing the substrate 102 and a hollow rotation motor 105.

As a substrate cooling mechanism, the cooling plate 106 is supported by a support mechanism 107 fixed in the hollow rotary motor.
As an ultraviolet irradiation mechanism, a lamp chamber 110 containing an ultraviolet lamp 108 and having a quartz window plate 109 is disposed on the upper part of the water vapor treatment chamber 101. FIG. 6 shows a cross-sectional direction of the ultraviolet lamp.

  The water vapor treatment chamber 101 has a water vapor introduction port 111, a water vapor injection nozzle 112, a water injection nozzle 113, an IPA vapor injection nozzle 114, and a pressurized carbon dioxide injection as mechanisms for introducing water vapor, IPA vapor, water, and pressurized carbon dioxide gas, respectively. A nozzle 115 is provided. The pressurized carbon dioxide back spray nozzle 116 is a mechanism that cools the substrate in place of the cooling plate 106.

  As a high-frequency ultrasonic irradiation mechanism, a high-frequency ultrasonic oscillator 117 is installed in the water jet nozzle 113. The shape of each injection nozzle is omitted in FIG. Further, the water vapor treatment chamber 101 includes an atmospheric purge gas inlet 118 and a discharge mechanism 119.

  As a mechanism for adding chemical components to water vapor / water, a chemical liquid injection device 122 composed of a metering pump is installed in the water vapor generator 120 and the ultrapure water supply line 121 to the water injection nozzle.

DESCRIPTION OF SYMBOLS 1 Evaporator 2 Evaporation heating block 3 Superheater 4 Superheating heating block 5 Constant flow pump 6 Pressure control needle valve 7 Pressure gauge 8 Thermometer 9 Thermometer 10 Valve for ultrapure water line 11 Valve for aqueous solution line 12 Steam introduction valve 13 Water vapor injection valve 14, 112 Water vapor injection nozzle 15, 101 Processing chamber 16 Processing surface 21, 102 Substrate 22 Spin rotation mechanism 23 Water vapor processing chamber 24, 108 Ultraviolet lamp 25, 109 Quartz window plate 26, 110 Lamp chamber 27 Gas inlet 28 Exhaust duct 31 Water vapor supply device 41 Injection nozzle 103 Support pin 104 Rotating body 105 Hollow motor 106 Cooling plate 107 Support mechanism 111 Water vapor introduction port 113 Water injection nozzle 114 IPA vapor injection nozzle 115, 116 Pressurized carbon dioxide injection nozzle 117 High Wave Ultrasonic oscillator 118 purge gas inlet 119 exhaust mechanism 120 steam generator 121 ultra-pure water supply line 122 liquid injector

Claims (2)

A resist film removing apparatus used in a lithography process, characterized by comprising means capable of spraying saturated water vapor at 70 to 200 ° C. onto a substrate at a spray pressure of 1 kg / cm ² or more and less than 10 kg / cm ^2. Resist film removing device. A resist film removing method used in a lithography process, which is 1 kg / cm ² 10 kg / cm ² A method comprising spraying saturated water vapor at 70 to 200 ° C. onto a substrate at a spray pressure of less than 70 ° C.

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