FOREIGN PARTICLE REMOVING METHOD, FORMATION METHOD, ARTICLE MANUFACTURING METHOD, FOREIGN PARTICLE REMOVING APPARATUS, SYSTEM, AND TEMPLATE

The present invention provides a foreign particle removing method of removing a foreign particle on a first member, comprising: supplying a composition to a supply region on the first member; setting a target region wider than the supply region on the first member, and pressing a second member against the composition supplied on the first member in the supplying; curing the composition on the first member after the pressing, in a state in which the composition and the second member are in contact with each other; and separating the second member from the first member after the curing, in a state in which the second member and the composition adhere to each other, thereby separating the composition from the target region of the first member.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a foreign particle removing method, a formation method, an article manufacturing method, a foreign particle removing apparatus, a system, and a template.

Description of the Related Art

In the manufacture of semiconductor devices, MEMS, and the like, a member such as a semiconductor substrate is cleaned. Conventionally, megasonic cleaning, two-fluid cleaning, RCA cleaning using a chemical solution, or the like is applied to cleaning of the member like this. Examples of the cleaning principles of these cleaning methods are a cleaning method of removing foreign particles adhered on a substrate by using the physical force of a hydrodynamic force (see Japanese Patent Laid-Open No. 8-318181), and a cleaning method of removing foreign particles in a lift-off manner by using the chemical action (for example, the etching effect) of a chemical solution (see Japanese Patent Laid-Open No. 2007-258462). Also, as a member cleaning method, each of Japanese Patent Publication Nos. 6765488 and 6480219 describes a cleaning method of forming a solid film on a member so that the solid film entraps foreign particles on the member, and removing the solid film by using a chemical solution.

Recently, as micropatterning in the manufacture of semiconductor devices and the like progresses, cleaning of a member such as a semiconductor substrate is required to remove even foreign particles having very small particle sizes (for example, a few tens of nm or less) from the member. However, in the cleaning method using the hydrodynamic force as described in Japanese Patent Laid-Open No. 8-318181, if the hydrodynamic force is increased in order to remove foreign particles having small particle sizes or an unnecessary material such as a polymer adhered on a member, a microstructure formed as an underlayer (underlying pattern) on the member is sometimes damaged. This damage to the underlayer of the member can similarly occur in the cleaning method using the chemical reaction of a chemical solution as described in Japanese Patent Laid-Open No. 2007-258462 as well. Therefore, the abovementioned cleaning methods are beginning to reach the limit of application regarding to the removal of foreign particles having small particle sizes. In addition, the cleaning methods described in Japanese Patent Publication Nos. 6765488 and 6480219 have the problems that foreign particles sometimes adhere on a member again when dissolving (removing) the solid film by using a chemical solution, and the environmental load and the cost burden of waste liquid treatment and the like are large.

As a member cleaning method, therefore, a cleaning method (also called a dry cleaning method in some cases) of removing foreign particles on a member by using an imprint system instead of using a chemical solution is attracting attention. As an example, Japanese Patent No. 5121549 describes a cleaning method of removing foreign particles on a template by pressing the template against a resin applied on a dummy wafer, and separating the template from the resin after the resin is cured. Also, Japanese Patent No. 5982996 describes a cleaning method of forming a resin film by bringing a planarizing member into contact with a resin applied on a mold as an object of foreign particle removal, curing the resin film, releasing the planarizing member from the resin film, and releasing the resin film from the mold. In the cleaning methods using the imprint system as described above, it is desirable to efficiently remove foreign particles on the member.

SUMMARY OF THE INVENTION

The present invention provides, for example, a technique capable of efficiently removing foreign particles on a member.

According to one aspect of the present invention, there is provided a foreign particle removing method of removing a foreign particle on a first member, comprising: supplying a composition to a supply region on the first member; setting a target region wider than the supply region on the first member, and pressing a second member against the composition supplied on the first member in the supplying, such that the composition on the first member spreads over the target region and entraps a foreign particle in the target region; curing the composition on the first member after the pressing, in a state in which the composition and the second member are in contact with each other; and separating the second member from the first member after the curing, in a state in which the second member and the composition adhere to each other, thereby separating the composition from the target region of the first member.

DESCRIPTION OF THE EMBODIMENTS

In the specification and the accompanying drawings, directions will be indicated on an XYZ coordinate system in which directions parallel to the surface (upper surface) of a member as an object of foreign particle removal are defined as the X-Y plane. Directions parallel to the X-axis, the Y-axis, and the Z-axis of the XYZ coordinate system are the X direction, the Y direction, and the Z direction, respectively. A rotation about the X-axis, a rotation about the Y-axis, and a rotation about the Z-axis are θX, θY, and θZ, respectively. Control or driving (movement) concerning the X-axis, the Y-axis, and the Z-axis means control or driving (movement) concerning a direction parallel to the X-axis, a direction parallel to the Y-axis, and a direction parallel to the Z-axis, respectively. In addition, control or driving concerning the θX-axis, the θY-axis, and the θZ-axis means control or driving concerning a rotation about an axis parallel to the X-axis, a rotation about an axis parallel to the Y-axis, and a rotation about an axis parallel to the Z-axis, respectively.

First Embodiment

A foreign particle removing method of the first embodiment according to the present invention will be explained below. The foreign particle removing method of this embodiment is a method of removing foreign particles on a member (first member), more specifically, a cleaning method (so-called dry cleaning method) of removing foreign particles on the member without using any chemical solution.

Foreign Particle Removing Method

The foreign particle removing method (cleaning method) of this embodiment will be explained below with reference toFIGS.1and2A to2F.FIG.1is a flowchart showing the foreign particle removing method of this embodiment.FIGS.2A to2Fare schematic views for explaining steps of the foreign particle removing method of this embodiment. Note that examples shown inFIGS.1and2A to2Fare merely typical examples, and the present invention is not limited to the examples shown inFIGS.1and2A to2F.

First, in step S11(a preparation step), a member1(a first member) as an object of foreign particle removal is prepared. In the following explanation, the member1as an object of foreign particle removal will be referred to as “a target member1” in some cases. The preparation step can also be understood as a step for loading a target member1into a foreign particle removing apparatus for removing foreign particles on the target member1. A configuration example of the foreign particle removing apparatus will be described later.

As shown inFIG.2A, the target member1can be a substrate on which a pattern is formed in a lithography step of manufacturing a semiconductor device or a flat panel display. Examples of the substrate are a semiconductor wafer or MEMS wafer on which a pattern (underlying pattern) is formed, a power semiconductor wafer, a display glass substrate (glass plate), or a bio-element. In this embodiment, an example in which a substrate is applied as the target member1will be explained. However, the target member1can also be an original plate to be used to form a pattern on a substrate in the lithography step. Examples of the original plate are an EUV exposure mask, a semiconductor exposure mask, a semiconductor imprint mold (template), a MEMS exposure mask, a power semiconductor exposure mask, and a display exposure mask. Note that MEMS is the abbreviation for Micro Electro Mechanical System, and EUV is the abbreviation for Extreme Ultraviolet.

In the example shown inFIG.2A, foreign particles2(particles) having various sizes adhere on the top surfaces (upper surfaces) and the bottom surfaces (lower surfaces) of a pattern3already formed in a pattern portion1aof the target member1and in a peripheral portion1bof the target member1. It is particularly difficult to remove extremely small foreign particles having particle sizes of 30 nm or less and foreign particles adhered on the bottom surfaces of the pattern3by the conventional cleaning methods such as megasonic cleaning and two-fluid cleaning. The pattern portion1aindicates a portion (region) of the target member1in which the pattern3is formed. In this embodiment, the pattern3formed in the pattern portion1ais configured as a pattern with concave and convex portions obtained by repetitively (for example, periodically) forming concave and convex portions. Also, the peripheral portion1bis an edge portion surrounding the pattern portion1aand indicates a portion (region) where bevel processing (for example, chamfering) is performed. In the following explanation, the peripheral portion1bof the target member1will be referred to as “the bevel portion1b” in some cases.

Then, in step S12(a supply step), as shown inFIG.2B, a composition4for entrapping and enclosing the foreign particles2on the target member1is supplied onto the target member1(a supply region). The composition4is supplied onto the target member1in a state in which the composition4has fluidity (that is, in a liquid state). Also, to avoid the composition4from extending outside the target member1(the bevel portion1b), the composition4is preferably not supplied on the bevel portion1b, that is, the composition4is preferably supplied only on the pattern portion1aof the target member1(that is, a portion except for the bevel portion).

As the composition4, a curable composition (for example, a resin) to be cured by receiving curing energy is used. The curable composition is a composition cured by light irradiation or heating. Among these, a photo-curable composition (photo-curable resin) cured by light irradiation contains at least a polymerizable compound and a photopolymerization initiator, and may further contain a nonpolymerizable compound or a solvent, as needed. The polymerizable compound is a compound that reacts with a polymerizing factor (a radical or the like) generated from the photopolymerization initiator and forms a film made of a polymer compound by a chain reaction (polymerization reaction). An example of the polymerizable compound is a radical polymerizable compound. The polymerizable compound is preferably a compound having one or more acryloyl groups or methacryloyl groups, that is, a (meth)acryloyl compound. The nonpolymerizable compound is at least one material selected from the group consisting of a sensitizer, a hydrogen donor, an internal mold release agent, a surfactant, an antioxidant, and a polymer component. Note that the viscosity (the viscosity at 25° C.) of the composition4is, for example, from 1 mPas (inclusive) to 100 mPas (inclusive).

In this embodiment, the composition4can be supplied (applied) on the target member1by using an apparatus that discharges the composition4by an inkjet method. However, the method of supplying (applying) the composition4on the target member1is not limited to the inkjet method, and it is possible to use any method capable of controlling the supply amount (for example, the coating film thickness of the composition4) of the composition4onto the target member1. For example, the composition4can be supplied on the target member1by using dispenser coating, spin coating, various printing methods such as screen printing, gravure printing, and offset printing, and dip coating.

Also, the supply amount of the composition4to be supplied on the target member1is preferably decided (set) based on the size of the foreign particle2adhered on the target member1, such that the film thickness of the composition4formed on the target member1through a pressing step (to be described later) becomes larger than the size of the foreign particle2. The size of the foreign particle2can be a measurement value obtained by measuring (inspecting) the size of the foreign particle2adhered on the target member1in advance, and can also be a predicted value obtained from a calculation (simulation) based on the empirical rules.

The wettability of the surface (upper surface) of the target member1is preferably as high as possible so that air bubbles are not involved between the target member1and the composition4and/or the composition4easily spreads on the target member1. That is, it is favorable to minimize the contact angle between the target member1and the composition4. The allowable range of this contact angle is preferably 2° or less, and more preferably 1° or less.

For this purpose, before the supply step (step S12), a process (lyophilization process (hydrophilization process)) of lyophilizing (hydrophilizing) the surface of the target member1with respect to the composition4is preferably performed on the target member1. This lyophilization process includes a process of removing organic contamination components on the target member1. Examples of the lyophilization process are baking, plasma ashing, atmospheric plasma treatment, alkali cleaning, and ozone water washing. As the lyophilization process, this embodiment can use the atmospheric plasma treatment that can be implemented with a simple apparatus configuration. When the target member1is sufficiently lyophilic, this lyophilization process can be omitted. When performing the lyophilization process, the etching amount is preferably so selected as to remove contamination components on the top surface layer as long as the surface layer of the target member1is not damaged. When the composition4is supplied on the target member1after the surface of the target member1is lyophilized in advance as described above, the capillary force allows the composition4to easily penetrate narrow channels (gaps) between the target member1and the foreign particles2adhered on it. Note that the lyophilization process can also be performed by an external apparatus of the foreign particle removing apparatus before the preparation step (step S11), for example, before the target member1is loaded into the foreign particle removing apparatus. Note also that a separation layer (for example, a fluorine-based layer) for facilitating separation (release) between the target member1and the composition4in a separation step (step S15) (to be described later) can be formed on the target member1before the supply step (step S12).

Subsequently, in step S13(a pressing step), a template5is pressed against the composition4on the target member1so that the composition4spreads over a target range (target region) of the target member1. More specifically, in this pressing step, after the template5is brought into contact with the composition4supplied on the target member1in the supply step as shown inFIG.2C, the composition4is spread on the target member1by the template5as shown inFIG.2D. In this step, the template5is pressed against the composition4on the target member1so that the composition4spreads over the target range of the target member1and entraps the foreign particles2within the target range. Note that the pressing step can be executed by a driving mechanism that drives the target member1and the template5relative to each other.

The target range of the target member1is a range within which foreign particles must be removed, and can include at least a part of the bevel portion1bin addition to the pattern portion1a. In this embodiment, the target range is set as a range including the whole bevel portion1b, that is, set on the whole surface (upper surface) of the target member1. Also, the template5is a member (second member) playing the role of a handle for spreading, on the target member1, the composition4supplied on the target member1in the supply step, and for separating (releasing) the composition4cured in a curing step (to be described later) from the surface of the target member1. The template5is preferably formed to have a size larger than the target member1(the target range), in order to effectively clean the whole of the end portion (edge) and the bevel portion1bof the target member1.

In the pressing step, as shown inFIG.3A, if the template5is pressed against the composition4on the target member1in a state in which the template5and the target member1are inclined relative to each other, it may become difficult to spread the composition4over the whole target range of the target member1. Consequently, as shown inFIG.3B, the foreign particle2sometimes remains on the target member1(for example, the bevel portion1b) even after a separation step (to be described later) is performed. Also, the composition4extends outside the target range of the target member1and the extended portion of the composition4remains as a foreign particle on the target member1after the separation step in some cases.

In the pressing step of this embodiment, therefore, it is possible to control the parallelism between the template5and the target member1and/or the force of pressing the template5against the composition4on the target member1, so that the composition4spreads over the whole target range of the target member1. The parallelism and/or the pressing force can also be so controlled that the composition4does not extend outside the target range of the target member1. For example, the parallelism between the template5and the target member1can be controlled by adjusting the relative postures (relative inclinations) of the template5and the target member1, such that a press surface5aof the template5and the upper surface of the target member1become parallel. The press surface5aof the template5is a surface (for example, a lower surface) to be pressed against the composition4on the target member1. Note that the parallelism and the pressing force can be controlled by a driving mechanism for driving the target member1and the template5relative to each other.

In the pressing step of this embodiment, as shown inFIG.2D, it is also possible to control the pressing (for example, the parallelism and/or the pressing force) of the template5against the composition4on the target member1while observing the spread of the composition4on the target member1by an image capturing device16. The image capturing device16includes a camera16aand an observation optical system16b,and can be so configured as to capture an image of the whole target range of the target member1in an image capturing field. This makes it possible to control the pressing of the template5against the composition4on the target member1so that the composition4spreads over the target range of the target member1and/or the composition4does not extend outside the target range of the target member1. The pressing step can also be controlled by time management, instead of the result of observation by the image capturing device16.

Then, in step S14(a curing step), as shown inFIG.2E, the composition4is cured by giving energy7to the composition4in a state in which the composition4on the target member1and the template5are in contact with each other. For example, when a photo-curable resin (for example, an ultraviolet curable monomer) is used as the composition4, light (ultraviolet light) as the energy7is emitted (given) to the composition4through the template5. In this case, the template5is preferably formed by a material capable of transmitting light (ultraviolet light), such as quartz. The composition4is not limited to a material that cures when irradiated with ultraviolet light, and can also be a material that cures by a polymerization reaction when irradiated with another energy such as X-ray or visible light, or a material that cures by thermal energy.

Subsequently, in step S15(a separation step), as shown inFIG.2F, the composition4is separated (released) from the target member1by extending the interval between the template5and the target member1in a state in which the composition4cured in the curing step and the template5adhere to each other. That is, the template5is separated together with the composition4from the target member1in a state in which the cured composition4including the foreign particles2and the template5adhere to each other. By using the separation step like this, it is possible to efficiently remove the foreign particles2on the target member1by simple processing, that is, to effectively clean the target member1, and this is advantageous in throughput as well.

To perform the abovementioned separation step, the adhesion between the template5and the composition4must be higher than that between the target member1and the composition4. Before the pressing step (step S13), therefore, a pre-process of improving the adhesion between the template5and the composition4is preferably performed on the template5. This pre-process can include a film formation step of forming (applying) an adhesive film (adhesive layer) that adheres to the composition4, on the surface (the press surface5a) of the template5. This film formation process can be performed by a general thin film formation method such as spraying, vapor deposition, or spin coating. The pre-process (an application process) can also be performed by an external apparatus of the foreign particle removing apparatus before the template5is loaded into the foreign particle removing apparatus.

The wettability of the surface (the press surface5a) of the template5is preferably as high as possible so that air bubbles are not involved between the template5and the composition4in the pressing step and/or the composition4easily spreads on the template5. That is, the contact angle between the template5and the composition4on the target member1is preferably decreased as much as possible in the pressing step. The allowable range of the contact angle between the template5and the composition4is preferably 2° or less, and more preferably 1° or less. This allowable range is favorably smaller than the contact angle between the target member1and the composition4by about 0.5° to 1°. For example, when a fluorine-based separation layer is formed on the target member1, the contact angle between the target member1and the composition4does not satisfy the above-described allowable range. Therefore, the spreading speed of the composition4on the template5is preferably increased by decreasing the contact angle between the template5and the composition4to 1° or less.

For this purpose, a process (lyophilization process (hydrophilization process)) of lyophilizing (hydrophilizing) the surface (the press surface5a) of the template5with respect to the composition4can be performed on the template5before the pressing step (step S13). This lyophilization process includes a process of removing organic contamination components on the surface (the press surface5a) of the template5. Examples of the lyophilization process are baking, atmospheric plasma treatment, ashing, alkali cleaning, and ozone water washing. In this embodiment, the atmospheric plasma treatment that can be implemented with a simple apparatus configuration can be used as the removing process. By thus lyophilizing the surface (the press surface5a) of the template5, it is possible to decrease the contact angle between the template5and the composition4in the pressing step, and facilitate spreading of the composition4on the template5. Note that the lyophilizing process can also be performed by an external apparatus of the foreign particle removing apparatus before the template5is loaded into the foreign particle removing apparatus.

Configuration of Template

A configuration example of the template5to be used in the foreign particle removing method of this embodiment will be explained below.FIGS.4A and4Bare views showing the configuration example of the template5.FIG.4Ais a view showing the template5from below (in the −Z direction), andFIG.4Bis an A-A sectional view of the template5shown inFIG.4A.

The template5to be used in the foreign particle removing method of this embodiment can be so configured that the press surface5ais a flat surface, and can also be configured so as to efficiently spread the composition4over the target range of the target member1in the pressing step (step S13). For example, in the pressing step (step S13), as the spread of the composition4approaches the edge of the target member1, the bevel portion1bof the target member1increases the interval between the template5and the target member1, so the spreading rate of the composition4decreases. On the press surface5a,therefore, the template5has a plurality of first groove portions5bradially extending so as to guide (assist) the spread of the composition4in the pressing step. On the press surface5aof the template5, the plurality of first groove portions5bcan be arranged in positions corresponding to the bevel portion1bof the target member1.

A width W of each first groove portion5bis preferably set at a width with which a predetermined capillary force can be generated for the composition4, and can be set at a few ten μm to a few hundred nm. A length L in the radial direction of each first groove portion5bis preferably set to be larger than the length of the bevel portion1bof the target member1, and can be set at, for example, 1 mm or more. As an example, each first groove portion5bof the template5has a width W of 100 nm, a length L of 2 mm, and a depth of 100 nm. By forming the plurality of first groove portions5bon the template5, it is possible to efficiently spread the composition4over the target range of the target member1by using the capillary force generated in each first groove portion5b.

On the press surface5a,the template5can also have a second groove portion5cformed into the shape of a frame so as to stop the spread of the composition4in the pressing step. The second groove portion5ccan be arranged in a position corresponding to the outer circumference of the target range of the target member1(for example, the edge of the target member1). In the example shown inFIGS.4A and4B, the whole of the circular target member1is the target range, so the second groove portion5cof the template5is formed into a circumferential shape (for example, a circular shape) along the edge of the target member1. By forming the second groove portion as described above on the template5, it is possible to stop the spread of the composition4within the target range of the target member1, and avoid the composition4from extending outside the target range.

Configuration of Foreign Particle Removing Apparatus

A configuration example of a foreign particle removing apparatus10will be explained below.FIG.5is a schematic view showing the configuration example of the foreign particle removing apparatus10of this embodiment. The foreign particle removing apparatus10of this embodiment is an apparatus that removes foreign particles on the target member1by executing the foreign particle removing method described above with reference toFIGS.1and2A to2F. The foreign particle removing apparatus10can include, for example, a stage11, a holding device12, a supply device13, a first processing device14, a second processing device15, an image capturing device16, a curing device17, and a control device18. The control device18is configured by a computer including a processor such as a CPU or an MPU or a logic circuit, and a storage device such as a memory, and controls a foreign particle removing process of removing foreign particles on the target member1by controlling each device of the foreign particle removing apparatus10. The control device18can also include a communication device for communicating with an external apparatus. Note that the CPU is the abbreviation for Central Processing Unit, and the MPU is the abbreviation for Micro Processing Unit.

The stage11is capable of holding the target member1(a first member) as an object of foreign particle removal by a vacuum suction force or an electrostatic force, and movable in the X and Y directions on a baseplate BP. That is, the stage11is a mechanism that moves in the X and Y directions while holding the target member1. In this embodiment, the stage11is so configured as to drive the target member1in only the X and Y directions. However, the stage11can also be so configured as to drive in the Z direction and the rotational direction of each axis. The holding device12is a mechanism that holds the template5(a second member) by a vacuum suction force or an electrostatic force, and drives the template5in the Z direction. In this embodiment, the holding device12is so configured as to drive the template5in only the Z direction. However, the holding device12may also be so configured as to drive the template5in the X and Y directions and the rotational direction of each axis. The stage11and the holding device12can form a driving mechanism (driving device) for driving the target member1and the template5relative to each other.

The supply device13is a mechanism that supplies (discharges or applies) the liquid composition4on the target member1. When the supply device13supplies the composition4on the target member1, the stage11places the target member1below the supply device13. The first processing device14is a mechanism that performs a lyophilizing process on the target member1. When the first processing device14performs the lyophilizing process on the target member1, the stage11places the target member1below the first processing device14. The second processing device15is a mechanism that performs a film formation process and the lyophilizing process on the template5. The second processing device15of this embodiment is supported by a moving mechanism19movable in the X and Y directions on the baseplate BP. When the second processing device15performs the film formation process and the lyophilization process on the template5, the moving mechanism19places the second processing device15below the template5.

The image capturing device16is a mechanism for observing (capturing an image of) the spread of the composition4on the target member1in the pressing step described above. The image capturing device16can include the camera16a(an image sensor) and the observation optical system16b.In this example shown inFIG.5, the image capturing device16is so configured as to capture an image of the spread of the composition4on the target member1, via a mirror MR and the template5. The curing device17is a mechanism for curing the composition4on the target member1in the above-described curing step. The curing device17can include an energy source17afor emitting energy (for example, ultraviolet light) for curing the composition4, and an irradiation optical system17bthat irradiates the composition4on the target member1with the energy emitted from the energy source17a.In the example shown inFIG.5, the curing device17cures the composition4on the target member1by irradiating the composition4with the energy, via the mirror MR and the template5.

Operations of Foreign Particle Removing Apparatus

Operation examples of the foreign particle removing apparatus10of this embodiment will be explained below. A series of operations of the foreign particle removing apparatus10are executed by the control device18by transmitting a signal to each device.

Operation from Loading of Target Member to Supply Step

First, a conveyor mechanism (not shown) conveys the target member1onto the stage11, and the stage11holds the target member1(a preparation step). Then, the stage11places the target member1below the first processing device14by driving the target member1, and the first processing device14performs a lyophilization process on the target member1. As this lyophilization process, the first processing device14can execute a process properly selected from, for example, baking, plasma ashing, atmospheric plasma processing, and alkali or ozone water washing, each of which can remove organic contamination components on the target member1.

Then, after the stage11places the target member1below the supply device13by driving the target member1, the supply device13supplies the liquid composition4on the target member1(the supply step). The supply device13can supply the composition4on the target member1by a method appropriately selected from, for example, an inkjet method, a dispenser method, and a printing method. Note that in the example shown inFIG.5, the first processing device14and the supply device13are formed as constituent elements of the foreign particle removing apparatus10. However, the first processing device14and/or the supply device13can also be formed as an external element (external apparatus) of the foreign particle removing apparatus10. In this case, the target member1on which the lyophilization process and/or the supply of the composition4is performed outside the foreign particle removing apparatus10is loaded into the foreign particle removing apparatus10.

The supply amount of the composition4to be supplied on the target member1by the supply device13will be explained below. The control device18obtains information (to be also referred to as foreign particle information hereinafter) indicating the size of a foreign particle adhered on the target member1. This foreign particle information can contain information indicating a typical size of foreign particles obtained by measuring the sizes of foreign particles on the target member1by using an external inspection apparatus. The typical size of foreign particles can be a maximum size of foreign particles adhered on the target member1, and can also be an average size thereof. When there are a plurality of target members1, a typical size can be obtained for each target member1. From the viewpoint of throughput, however, it is also possible to obtain a typical size from several target members1extracted as samples (representatives) from the plurality of target members1. In this case, a maximum size or an average size of foreign particles on the several extracted target members1can be used as a typical size.

The control device18also obtains information (to be also referred to as pattern information hereinafter) indicating the height (for example, the height of concave and convex portions) of the pattern3formed on the target member1. The pattern information can be information indicating the measurement result of the height of the pattern3of the target member1, and can also be design information of the pattern3of the target member1.

Then, based on the foreign particle information and the pattern information, the control device18decides the supply amount of the composition4so that the film thickness T of the composition4to be formed between the target member1and the template5through the above-described pressing step satisfies equation (1) below. “α” in equation (1) can appropriately be set between 1 and 100, and α=1.5 is set in this embodiment by taking account of cure shrinkage of the composition4in the curing step and the measurement accuracy of the sizes of foreign particles. The control device18controls the supply device13by transmitting an instruction signal corresponding to the decided supply amount of the composition4to the supply device13.

T=(maximum size of foreign particles+height of pattern 3)×α, α<1  (1)

Operation from Loading of Template to Pressing Step

A conveyor mechanism (not shown) conveys the template5onto the holding device12, and the holding device12holds the template5. Then, the moving mechanism19places the second processing device15below the template5, and the second processing device15performs a film formation process on the template5. The film formation process is a process of forming an adhesive film (adhesive layer) for improving the adhesion between the template5and the composition4, on the press surface5aof the template5, and can include surface treatment such as silane coupling treatment, silazane treatment, or deposition of a thin organic film. When an adhesive film like this is formed on the press surface5aof the template5, it is possible to adhere the template5and the composition4and completely separate (release) the template5together with the composition4from the target member1in the above-described separation step. That is, it is possible to efficiently and reliably remove foreign particles from the target member1. Note that the formation of the adhesive film may also be omitted depending on the components of the composition4or the configuration and material of the template5.

Subsequently, the second processing device15performs a lyophilization process on the template5. The second processing device15can execute, as the lyophilization process, a process appropriately selected from, for example, baking, plasma ashing, atmospheric plasma treatment, and alkali or ozone water washing, each of which can remove organic contamination components on the template5. Note that the lyophilization process can be omitted if the surface of the above-described adhesive layer is sufficiently lyophilic. When performing the lyophilization process, the etching amount is preferably so selected as to remove contamination components in the top surface layer as long as the adhesive layer is not damaged. Note also that in the example shown inFIG.5, the second processing device15is formed as a constituent element of the foreign particle removing apparatus10. However, the second processing device15can also be formed as an external element (external apparatus) of the foreign particle removing apparatus10. In this case, the template5having undergone the film formation process and/or the lyophilization process outside the foreign particle removing apparatus10is loaded into the foreign particle removing apparatus10.

Then, after the stage11places (positions) the target member1below the template5by driving the target member1, the holding device12moves down the template5and presses the template5against the composition4on the target member1(the pressing step). The time of the pressing step (that is, the time during which the composition is spread on the target member1) can properly be set in accordance with the material, properties, and the like of the composition4so that the composition4can sufficiently enclose foreign particles within the target range of the target member1.

In the pressing step, while the image capturing device16is observing uniformity/nonuniformity of the spread of the composition4on the target member1, the pressing (for example, the parallelism and/or the pressing force) of the template5against the composition4on the target member1can be controlled. For example, the control device18can detect the outer circumference of the composition4and/or the edge of the target member1by performing well-known image processing on an image obtained from the image capturing device16, thereby observing (monitoring) uniformity/nonuniformity of the spread of the composition4on the target member1. If the nonuniformity of the spread of the composition4is detected, the control device18causes the stage11and the holding device12to control the relative postures of the template5and the target member1and/or the pressing force on the template5so as to correct the nonuniformity. This makes it possible to uniformly spread the composition4over the target range of the target member1, and reliably remove foreign particles on the bevel portion1bincluded in the target range as well.

In the pressing step, a gas for accelerating disappearance of air bubbles involved between the template5and the target member1and/or avoiding defective curing of the composition4caused by inhibition of oxygen can be supplied from a gas supply nozzle (not shown) formed in the holding device12. Examples of the gas are He, H2, and a gas mixture thereof. However, even when air bubbles are involved between the template5and the composition4, the gas need not be supplied from the gas supply nozzle if the adhesion between the template5and the composition4has no problem.

Operation from Curing Step to Release Step

When the composition4has spread over the target range of the target member1in the pressing step, the control device18transmits a signal giving an instruction to cure the composition4to the curing device17. Upon receiving this signal, the curing device17emits energy (for example, ultraviolet light) for curing the composition4from the energy source17a,and irradiates the composition4with this energy via the irradiation optical system17b,the mirror MR, and the template5(the curing step). As a consequence, the composition4between the template5and the target member1can be cured.

In the energy source17a,a combination of the material and the wavelength can appropriately be selected so that the emitted energy can be transmitted through the template5. In this embodiment, the template5is made of quartz, so ultraviolet light having a wavelength of 365 nm is adopted as the energy to be emitted from the energy source17a.Note that the energy to be emitted from the energy source17ais not limited to the ultraviolet light having a wavelength of 365 nm, and it is also possible to adopt, for example, visible light, ultraviolet light having a wavelength other than 365 nm, infrared light, X-ray, radiation, or an electron beam, in accordance with the materials of the template5and the composition4.

In the curing step, it is possible to appropriately set the energy intensity (light intensity) with which the composition4is irradiated and the irradiation time (exposure time), so that the composition4can sufficiently cure, that is, the composition4cures to the target hardness. The curing rate of the composition4can change in accordance with the amount of oxygen in the surrounding atmosphere. Therefore, it is also possible to detect the amount of oxygen in the peripheral atmosphere by using a sensor or the like, and set the energy intensity and/or the irradiation time based on the detection result.

In the abovementioned step, the composition4on the target member1entraps (encloses) foreign particles within the target range of the target member1by spreading over the target range by the capillary force and the wettability, and becomes separable from the target member1by shrinkage by curing (cure shrinkage).

Then, the holding device12raises the template5and separates the template5from the target member1(the separation step). Since the template5and the cured composition4adhere to each other in this state, the composition4is also separated together with the template5from the target member1. The rate at which the template and the target member1are separated can be so set that the pattern of the target member1is not damaged. By thus separating the template5together with the composition4from the target member1, it is possible to efficiently remove foreign particles on the target member1with simple processing, and this can be advantageous in throughput as well.

When separating the template5and the composition4from the target member1, the target member1may be electrified (called release electrification) and may attract surrounding foreign particles by the electrostatic force in some cases. Therefore, the separation step is preferably executed while removing static electricity from the template5, the composition4and/or the target member1by using an ionizer (not shown). Note that the composition4is adhered on the template5after the separation step is performed, the template5can be replaced or cleaned when performing the foreign particle removing process on a new target member1.

When the separation step is completed, the target member1is separated from the stage11and unloaded by the conveyor mechanism (not shown). In addition, the template5is separated from the holding device12and unloaded by the conveyor mechanism (not shown). When separating the target member1from the stage11and/or when separating the template5from the holding device12, it is favorable to remove electrical charge by using an ionizer (not shown).

In the foreign particle removing method of this embodiment as described above, after the liquid composition4is supplied on the target member1, the template5is pressed against the composition4such that the composition4spreads over the target range of the target member1and entraps foreign particles within the target range. Then, the composition4is cured in a state in which the template5and the composition4on the target member1are in contact with each other, and the template5is separated together with the cured composition4from the target member1in a state in which the template5and the composition4adhere to each other. Consequently, it is possible to efficiently remove the foreign particles2on the target member1with a simple process, and this is advantageous in throughput as well.

Second Embodiment

The second embodiment according to the present invention will be explained below. This embodiment basically takes over the first embodiment and can follow the first embodiment except items to be explained below.

A bevel portion1b(a peripheral portion) of a target member1such as a wafer or a substrate sometimes includes an edge region having little influence on pattern formation in a subsequent lithography step. An edge region like this is also called an edge exclusion region (to be also referred to as an EE region hereinafter), and can be understood as a region excluded from evaluation of the presence/absence of a foreign particle in the pattern formation.

FIGS.6A to6Fare schematic views for explaining steps of a foreign particle removing method of this embodiment in chronological order. These steps shown inFIGS.6A to6Frespectively correspond to the steps shown inFIGS.2A to2Fdescribed earlier, and are similar to the steps shown inFIGS.2A to2Fof the first embodiment. However, the target range of the target member1shown inFIGS.6A to6Fdiffers from that shown inFIGS.2A to2F.

In this embodiment, the target range (a range within which foreign particles must be removed) of the target member1is so set as not to include an EE region8. That is, the target range of the target member1is set as a range including a pattern portion1aand a part of the bevel portion1bfrom which the EE region8is excluded. A template5to be used when the EE region8is taken into account can be set to have a size larger than the target range of the target member1, and can also be set to have a size smaller than the target member1itself. To facilitate handling of the template5, the template5favorably has the same size as or a size larger than that of the target member1.

Third Embodiment

The third embodiment according to the present invention will be explained below. In this embodiment, a system100including a foreign particle removing apparatus10explained in the first embodiment will be explained. This embodiment basically takes over the first embodiment and can follow the first embodiment except items to be explained below. This embodiment can also take over the second embodiment.

FIG.7is a schematic view showing a configuration example of the system100of this embodiment. The system100of this embodiment includes the foreign particle removing apparatus10and a formation apparatus20. In the system100of this embodiment, a conveyor apparatus30connects the foreign particle removing apparatus10and the formation apparatus20by inline, and conveys a target member1, from which foreign particles are removed by the foreign particle removing apparatus10, into the formation apparatus20.

As explained in the first embodiment, the foreign particle removing apparatus10is an apparatus for removing foreign particles on the target member1. As described above, the target member1can be a substrate on which a pattern is formed by the formation apparatus20and/or an original plate having a pattern to be transferred onto a substrate by the formation apparatus20. The formation apparatus20is an apparatus for forming a pattern on a substrate by using the target member1from which foreign particles are removed by the foreign particle removing apparatus10. The formation apparatus20of this embodiment can be configured as a lithography apparatus for transferring a pattern of an original plate onto a substrate. For example, when the target member1is a substrate, the formation apparatus20transfers a pattern onto the substrate from which foreign particles are removed by the foreign particle removing apparatus10. When the target member1is an original plate, the formation apparatus20transfers a pattern of the original plate from which foreign particles are removed by the foreign particle removing apparatus10onto a substrate. Examples of the lithography apparatus configuring the formation apparatus20are an exposure apparatus for exposing a substrate with pattern light having passed through an original plate (mask or reticle), and an imprint apparatus for forming a pattern of an imprint material on a substrate by using an original plate (mold).

Next, an operation example of the system100of this embodiment will be explained. In this embodiment, an example in which the target member1from which foreign particles are removed by the foreign particle removing apparatus10is a substrate and the formation apparatus20is an imprint apparatus will be explained.

A substrate is loaded into the system100from a coater/developer apparatus. The coater/developer apparatus can be connected inline to the foreign particle removing apparatus10and the formation apparatus20in the system100, and can also stand alone. However, the coater/developer apparatus is preferably connected inline from the viewpoints of foreign particle adhesion and contamination. In the coater/developer apparatus, a substrate is coated with a mask material such as SOC/SOG, and conveyed to the foreign particle removing apparatus10connected inline.

In the system100of this embodiment, the foreign particle removing apparatus10performs a foreign particle removing process on a substrate before the substrate is loaded into the formation apparatus20(an imprint apparatus). This foreign particle removing process is explained in the first embodiment, so an explanation thereof will be omitted. The substrate having undergone the foreign particle removing process performed by the foreign particle removing apparatus10is conveyed into the formation apparatus20connected inline to the foreign particle removing apparatus10, and a pattern formation process (imprint process) is performed. In this imprint process, an imprint material is supplied on the substrate, and a quartz mold (template) on which fine concave and convex portions are formed is brought into contact with the imprint material on the substrate. Then, the imprint material is cured in the state in which the imprint material on the substrate and the mold are in contact with each other, and the mold is separated (released) from the cured imprint material on the substrate. Consequently, the pattern of the mold is transferred onto the imprint material on the substrate, so the pattern of the cured product of the imprint material can be formed on the substrate.

In this imprint process, if a foreign particle exists (adheres) on the substrate, for example, if an inorganic foreign particle of about 80 nm or less exists, a mold having a pattern with concave and convex portions of about 20 nm may be damaged. Once the mold is damaged, a defect is formed on the pattern of the imprint material formed on the substrate in the subsequent imprint process using the mold. Accordingly, foreign particle management for a substrate and an original plate (mold) is a very important problem. The foreign particle removing apparatus10of this embodiment has a simple apparatus configuration and can remove very small foreign particles as well, and hence is very suitable as a method of solving this problem.

In the system100of this embodiment, after the foreign particle removing apparatus10performed the foreign particle removing process, the formation apparatus20(an imprint apparatus) performed the pattern formation process (imprint process). Consequently, it was confirmed that until an increase amount ADD of a defect density DD (defect/cm2) became one defect/cm2, the number of substrates to be processed rapidly increased from a few lots to a few hundred lots depending on the presence/absence of the foreign particle removing apparatus10.

Embodiment of Article Manufacturing Method

An article manufacturing method according to the embodiment of the present invention is suitable for manufacturing an article, for example, a microdevice such as a semiconductor device or a device having a microstructure. The article manufacturing method of this embodiment includes a foreign particle removing step of removing foreign particles on a target member, a formation step of forming a pattern on a substrate, a processing step of processing the substrate on which the pattern is formed in the formation step, and a manufacturing step of manufacturing an article from the substrate processed in the processing step. In the foreign particle removing step, foreign particles on the target member are removed by using the abovementioned foreign particle removing method. The target member is a substrate on which a pattern is formed in the formation step and/or an original plate having a pattern to be transferred onto a substrate in the formation step. The manufacturing method further includes other known steps (oxidation, film formation, deposition, doping, planarization, etching, resist removal, dicing, bonding, packaging, and the like). The article manufacturing method of this embodiment is more advantageous than the conventional methods in at least one of the performance, quality, productivity, and production cost of the article.

When using an imprint apparatus as a formation apparatus for forming a pattern on a substrate in the formation step, the pattern of a cured product formed by the imprint apparatus is used permanently for at least some of various kinds of articles or temporarily when manufacturing various kinds of articles. The articles are an electric circuit element, an optical element, a MEMS, a recording element, a sensor, a mold, and the like. Examples of the electric circuit element are volatile and nonvolatile semiconductor memories such as a DRAM, an SRAM, a flash memory, and an MRAM and semiconductor elements such as an LSI, a CCD, an image sensor, and an FPGA. Examples of the mold are a mold for imprint and the like.

The pattern of the cured product is directly used as the constituent member of at least some of the above-described articles or used temporarily as a resist mask. After etching or ion implantation is performed in the substrate processing step, the resist mask is removed.

Next, a specific method of manufacturing an article will be described. In this embodiment, an example using an imprint apparatus (imprint process) will be explained. As shown inFIG.8A, a substrate1zsuch as a silicon wafer with a target material2zto be processed, such as an insulator, formed on the surface is prepared. Next, an imprint material3zis applied to the surface of the target material2zby an inkjet method or the like. A state in which the imprint material3zis applied as a plurality of droplets onto the substrate is shown here.

As shown inFIG.8B, a side of a mold4zfor imprint, where a pattern with concave and convex portions is formed, is directed to face the imprint material3zon the substrate. As shown inFIG.8C, the mold4zand the substrate1zto which the imprint material3zis applied are brought into contact with each other, and a pressure is applied. The gap between the mold4zand the target material2zis filled with the imprint material3z.In this state, by irradiating the imprint material3zwith energy for curing through the mold4z,the imprint material3zis cured.

As shown inFIG.8D, after the imprint material3zis cured, the mold4zis separated from the substrate1z. Then, the pattern of the cured product of the imprint material3zis formed on the substrate1z. In the pattern of the cured product, the concave portion of the mold corresponds to the convex portion of the cured product, and the convex portion of the mold corresponds to the concave portion of the cured product. That is, the pattern with concave and convex portions in the mold4zis transferred to the imprint material3z.Note that a Residual Layer Thickness portion (an RLT portion, also called a residual film thickness) (not shown) having a thickness of about a few ten nm remains in the concave portion of the cured product.

As shown inFIG.8E, by etching the resultant material including the RLT portion by using the pattern of the cured product as an etching resistant mask, a portion of the surface of the target material2zwhere the cured product does not exist or remains thin is removed to form a groove5z.As shown inFIG.8F, by removing the pattern of the cured product, an article with the grooves5zformed in the surface of the target material2zcan be obtained. Here, the pattern of the cured product is removed. However, instead of removing the pattern of the cured product after processing, it may be used as, for example, an interlayer dielectric film included in a semiconductor element or the like, that is, a constituent member of an article.

Other Embodiments

This application claims the benefit of Japanese Patent Application No. 2022-073675, filed Apr. 27, 2022, which is hereby incorporated by reference herein in its entirety.