JP6571028B2 - Pattern formation method - Google Patents

Description

Embodiments of the present invention relates to a pattern formation how.

  One technique used in the manufacturing process of a semiconductor device is imprint lithography capable of forming a nanoscale fine pattern. In this imprint lithography, a template in which a concavo-convex pattern is dug is pressed against a resist on a wafer, whereby a resist pattern is formed on a substrate to be processed.

  In such pressing, excessive resist that has oozed out of the pattern formation region may remain as a resist residue on the wafer or the like due to curing after pressing. For example, when impressing on the resist while the template is on the resist residue during imprinting of adjacent shots, unexpected stress is applied to the template, increasing the risk of pattern damage and the like. For this reason, it is desired to easily reduce pattern defects in imprint lithography.

Japanese Patent No. 5806501 Japanese Patent No. 5558327

  The problem to be solved by the present invention is to provide a pattern forming method capable of easily reducing pattern defects.

According to the embodiment, a pattern forming method is provided. The pattern forming method includes a first dropping step, the second dropping step, and contacting step, hardening and step. In the first dropping step, a first resist having a first characteristic is dropped onto a first region of the imprint shot on the substrate. In the second dropping step, a second resist is dropped on a second region outside the first region in the imprint shot. In the contacting step, the first and second resists are brought into contact with the template pattern formed on the template. Wherein in the curing step, while the first and second resist filled in the template pattern, before Symbol faster curing the second resist than the first resist, the first and second resist is cured. The first resist and the second resist have different components.

FIG. 1 is a diagram illustrating a configuration of an imprint apparatus according to the first embodiment. FIG. 2 is a diagram for explaining the processing procedure of the imprint process according to the first embodiment. FIG. 3 is a view for explaining a resist arrangement region according to the first embodiment. FIG. 4 is a diagram for explaining the curing speed of the resist. FIG. 5 is a diagram for explaining the resist dropping method according to the first embodiment. FIG. 6 is a view for explaining a resist pattern formation region according to the first embodiment. FIG. 7 is a diagram for explaining an imprint process when one type of resist is used. FIG. 8 is a view for explaining a resist pattern formation region according to the second embodiment. FIG. 9 is a diagram for explaining the resist droplet size according to the third embodiment.

  Hereinafter, a pattern forming method and an imprint apparatus according to embodiments will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to these embodiments.

(First embodiment)
FIG. 1 is a diagram illustrating a configuration of an imprint apparatus according to the first embodiment. The imprint apparatus 101 is a semiconductor manufacturing apparatus that transfers a template pattern of a template Tx, which is a mold substrate, to a transfer target substrate such as a wafer WA. The imprint apparatus 101 according to this embodiment forms a resist pattern using two types of resists having different characteristics (physical characteristics and the like).

  The template Tx is an original plate used in imprint lithography such as NIL (Nano Imprint Lithography). The template Tx is formed using a member that transmits light. The member that transmits light may be quartz glass or a transparent resin. The template Tx has a three-dimensional template pattern formed on the front surface (lower surface) side.

  The imprint apparatus 101 includes an original stage 2, a substrate chuck 4, a sample stage 5, a reference mark 6, an alignment sensor 7, droplet dropping devices (dispensers) 8A and 8B, a stage base 9, a light source 10, and a controller 20.

  The sample stage 5 places a wafer WA, which is a substrate to be processed, and moves in a plane (in a horizontal plane) parallel to the placed wafer WA. The sample stage 5 moves the wafer WA to the lower side of the droplet dropping devices 8A and 8B when the resists 51A and 51B as transfer materials are dropped on the wafer WA, and performs the transfer process to the wafer WA. The wafer WA is moved to the lower side of the template Tx.

  A substrate chuck 4 is provided on the sample stage 5. The substrate chuck 4 fixes the wafer WA at a predetermined position on the sample stage 5. A reference mark 6 is provided on the sample stage 5. The reference mark 6 is a mark for detecting the position of the sample stage 5 and is used for alignment when the wafer WA is loaded onto the sample stage 5.

  The original stage 2 is provided on the bottom side (wafer WA side) of the stage base 9. The original stage 2 fixes the template Tx at a predetermined position from the back side of the template Tx (the surface on which the template pattern is not formed) by vacuum suction or the like.

  The stage base 9 supports the template Tx by the original stage 2 and presses the template pattern (circuit pattern or the like) of the template Tx against the resists 51A and 51B on the wafer WA. The stage base 9 moves in the vertical direction (vertical direction), thereby pressing the template Tx against the resists 51A and 51B and pulling the template Tx away from the resists 51A and 51B (release). The resists 51A and 51B used for imprinting include, for example, a resin (photocuring agent) having photocurability and the like. An alignment sensor 7 is provided on the stage base 9. The alignment sensor 7 is a sensor that detects the position of the wafer WA and the position of the template Tx.

  The droplet dropping device 8A is a device that drops the resist 51A on the wafer WA by an inkjet method. An ink jet head (a head 41A described later) provided in the droplet dropping device 8A has a plurality of fine holes for ejecting droplets of the resist 51A.

  The droplet dropping device 8B is a device that drops the resist 51B on the wafer WA by an inkjet method. The ink jet head (head 41B described later) provided in the droplet dropping device 8B has a plurality of fine holes for ejecting droplets of the resist 51B.

  The inkjet method can supply necessary and sufficient resists 51A and 51B onto the wafer WA in consideration of the coverage and directionality of the fine pattern of the template Tx. For this reason, the ink jet method is excellent in the filling efficiency of the film thickness controllability of the resists 51A and 51B.

  The light source (light irradiation unit) 10 is a device that emits light, and is provided above the stage base 9. The light source 10 emits light from above the template Tx in a state where the template Tx is pressed against the resists 51A and 51B. The light emitted from the light source 10 may be any light such as visible light, infrared light, and ultraviolet light as long as it can cure the resists 51A and 51B.

  Although not shown, the controller 20 is connected to each component of the imprint apparatus 101 and controls each component. The controller 20 controls the droplet dropping devices 8A and 8B when the resists 51A and 51B are dropped on the template Tx.

  The controller 20 causes the droplet dropping device 8A to drop the resist 51A onto a first region (first resist region 21A described later) in the imprint shot. Further, the controller 20 causes the droplet dropping device 8B to drop the resist 51B onto the second region (second resist region 21B described later) in the imprint shot.

  The controller 20 controls the droplet dropping devices 8A and 8B simultaneously to drop the resists 51A and 51B on the wafer WA at the same time. The controller 20 may operate the droplet dropping devices 8A and 8B at different timings. In this case, the controller 20 drops one of the resists 51A and 51B on the wafer WA and then drops the other on the wafer WA.

  When imprinting on the wafer WA, the wafer WA placed on the sample stage 5 is moved to just below the droplet dropping devices 8A and 8B. Then, resists 51A and 51B are dropped at predetermined shot positions on the wafer WA.

  Thereafter, the wafer WA on the sample stage 5 is moved directly below the template Tx. Then, the template Tx is pressed against the resists 51A and 51B on the wafer WA. In other words, the template Tx and the resists 51A and 51B are brought into contact with each other. The template Tx and the resists 51A and 51B are brought into contact with each other for a predetermined time.

  In the imprint apparatus 101, the light source 10 irradiates the resists 51A and 51B with light while filling the template patterns with the resists 51A and 51B. The resist 51B is a resist that cures faster than the resist 51A. In other words, the resist 51B has a photocuring characteristic that begins to cure with a light irradiation amount (dose amount) lower than that of the resist 51A.

  Therefore, when the resists 51A and 51B are simultaneously irradiated with light, the resist 51B is cured first. Then, after the curing of the resist 51B is completed, the curing of the resist 51A is completed. Thereby, the transfer pattern corresponding to the template pattern is patterned on the resists 51A and 51B on the wafer WA. Thereafter, an imprint process for the next shot is performed. When the imprint process for all shots on the wafer WA is completed, the wafer WA is unloaded.

  Here, the components of the resists 51A and 51B will be described. The main components of the resists 51A and 51B are composed of monomers having a molecular weight smaller than about 100. Further, the resists 51A and 51B have, for example, at least one relationship of (1) and (2) below.

(1) The molar ratio A1 with respect to the whole amount of the UV curing reaction initiator contained in the main component of the resist 51A and the molar ratio B1 with respect to the whole amount of the UV curing reaction initiator contained in the main component of the resist 51B are A1 < It has a relationship of B1.
(2) The molar ratio A2 with respect to the whole amount of the crosslinking agent contained in the main component of the resist 51A and the molar ratio B2 with respect to the whole amount of the crosslinking agent contained in the main component of the resist 51B have a relationship of A2 <B2. ing.

  Next, the processing procedure of the imprint process will be described. FIG. 2 is a diagram for explaining the processing procedure of the imprint process according to the first embodiment. FIG. 2 shows a sectional view of the wafer WA, the template Tx, and the like in the imprint process.

  Resist 51A, 51B is dropped on the upper surface of the wafer WA. For example, the resist 51B is dropped on the outer region of the imprint shot on the wafer WA. On the other hand, the resist 51A is dropped on, for example, an inner area of the imprint shot on the wafer WA.

  Then, as shown in FIG. 2A, the template Tx is moved to the wafer WA side, and as shown in FIG. 2B, the template Tx is pressed against the resists 51A and 51B. In other words, the template Tx and the resists 51A and 51B are brought into contact with each other. As a result, the resists 51A and 51B flow following the template pattern shape. As described above, when the template Tx in which the template pattern which is the concave and convex pattern is dug is brought into contact with the resists 51A and 51B, the resists 51A and 51B flow into the template pattern due to a capillary phenomenon.

  Then, as shown in FIG. 2C, light 50 is irradiated from the back side of the template Tx while filling the resists 51A and 51B into the template Tx. Thereby, the light 50 passes through the template Tx and is irradiated to the resists 51A and 51B. As a result, the resist 51B is cured, and then the resist 51A is cured. In other words, the resist 51B is cured faster than the resist 51A.

  Then, as shown in FIG. 2D, the template Tx is released from the resist patterns 51Ax and 51Bx formed by curing the resists 51A and 51B. As a result, resist patterns 51Ax and 51Bx obtained by inverting the template pattern are formed on the wafer WA. By performing such an imprint process, the resist patterns 51Ax and 51Bx are formed on the wafer WA in a three-dimensional shape.

  Next, an arrangement region (dropping position) in the imprint shot of the resists 51A and 51B will be described. FIG. 3 is a view for explaining a resist arrangement region according to the first embodiment. FIG. 3 shows a top view of the imprint shot.

  The inner area of the imprint shot is the first resist area 21A, and the outer area is the second resist area 21B. The first resist region 21A is a region where the resist 51A is dropped. The second resist region 21B is a region where the resist 51B is dropped.

  The second resist region 21B is a substantially rectangular annular region and includes the outermost peripheral portion of the imprint shot. The first resist region 21A is a substantially rectangular region and includes the central portion of the imprint shot. The second resist region 21B is a region outside the first resist region 21A, and is disposed so as to surround the first resist region 21A.

  In the present embodiment, the resist 51B that hardens before the resist 51A is dropped onto the second resist region 21B outside the first resist region 21A. Thereby, when the light 50 is irradiated to the resists 51A and 51B, the resist 51B arranged in the outer region of the imprint shot is cured before the resist 51A arranged in the inner region.

  FIG. 4 is a diagram for explaining the curing speed of the resist. FIG. 4 shows the relationship between the dose amount (light irradiation amount) of the light 50 to the resists 51A and 51B and the curing degree of the resists 51A and 51B. The horizontal axis of the graph shown in FIG. 4 is the dose of light 50, and the vertical axis is the degree of cure.

  The curing characteristic 31A is a curing characteristic of the resist 51A, and the curing characteristic 31B is a curing characteristic of the resist 51B. The resist 51B begins to harden with a smaller dose than the resist 51A. Then, the resist 51B is cured with a smaller dose than the resist 51A. Further, the dose amount at which the curing of the resist 51A starts is larger than the dose amount at which the curing of the resist 51B is completed. That is, (a dose amount at which the curing of the resist 51A starts)> (a dose amount at which the curing of the resist 51B is completed). Due to such characteristics, the curing of the resist 51A is started after the curing of the resist 51B is completed.

  Note that (a dose amount at which the curing of the resist 51A starts) <(a dose amount at which the curing of the resist 51B is completed) may be satisfied. Further, (a dose amount at which the curing of the resist 51A starts) = (a dose amount at which the curing of the resist 51B is completed) may be used.

  The light source 10 of this embodiment irradiates the light 50 to a predetermined dose amount D1 when the filling of the resists 51A and 51B into the template pattern is started. Thereby, the curing of the resist 51B proceeds, and the resist 51B is cured to a predetermined degree of curing C1.

  In the imprint apparatus 101, the light source 10 continues to irradiate the light 50 while continuing to fill the template patterns of the resists 51A and 51B. Thus, after the predetermined time has elapsed, the filling and curing of the resist 51B are completed. Thereafter, when the filling of the resist 51A is completed, the light source 10 emits a dose 50 of light 50 at which the hardening of the resist 51A starts. And the light source 10 continues irradiation of the light 50, and advances hardening of the resist 51A. The light source 10 continues irradiation with the light 50 until the resist 51A is completely cured.

  As described above, in the present embodiment, the resist pattern is applied to the template pattern in a state where the speed at which the resist 51B flows out of the second resist area 21B is slower than the speed at which the resist 51A flows out of the first resist area 21A. 51A and 51B are filled. As a result, the resist 51B is cured faster than the resist 51A.

  Note that after the resist 51B is cured to a predetermined degree of cure C1, the light source 10 may stop or reduce the irradiation of the light 50 until the filling of the resist 51B is completed. In this case, after the filling of the resist 51B is completed, the light source 10 resumes or increases the irradiation of the light 50. Thus, the resist 51B may be filled into the template pattern before the resist 51B is completely cured.

  Further, the light source 10 may stop or reduce the irradiation of the light 50 until the filling of the resist 51A is completed. In this case, after the filling of the resist 51A is completed, the light source 10 starts, resumes, or increases the irradiation of the light 50. Thus, the resist 51A may be filled into the template pattern before the resist 51A is completely cured.

  FIG. 5 is a diagram for explaining the resist dropping method according to the first embodiment. FIG. 5 shows a top view of the heads 41A and 41B included in the droplet dropping devices 8A and 8B, and a first resist region 21A and a second resist region 21B.

  The head 41A has a plurality of fine holes for ejecting droplets of the resist 51A. The fine holes of the head 41A are arranged in a row in the first direction (here, the y direction). The head 41A moves in the second direction (here, the x direction) and passes over the first resist region 21A.

  The head 41B has a plurality of fine holes for ejecting droplets of the resist 51B. The fine holes of the head 41B are arranged in a row in the first direction (here, the y direction). The head 41B moves in the second direction (here, the x direction) and passes over the second resist region 21B.

  The heads 41A and 41B are configured to be movable in the same direction at the same time, for example. When the resists 51A and 51B are dropped onto the wafer WA, the heads 41A and 41B are moved in the direction of the imprint shot (first resist area 21A and second resist area 21B).

  For example, the length in the y direction of the region where the fine holes are arranged in the head 41A is longer than the length of the first resist region 21A in the y direction. In addition, the length in the y direction of the region where the fine holes are arranged in the head 41B is longer than the length in the y direction of the second resist region 21B, for example.

  The head 41A drops the resist 51A when passing over the first resist region 21A, and stops dropping the resist 51A at other positions. The head 41B drops the resist 51B when passing over the second resist region 21B, and stops dropping the resist 51B at other positions. By this operation, the resist 51A is disposed on the first resist region 21A, and the resist 51B is disposed on the second resist region 21B.

  FIG. 6 is a view for explaining a resist pattern formation region according to the first embodiment. The upper side of FIG. 6 shows the cross-sectional shape of the resist patterns 51Ax, 51Bx and the like. Further, the lower side of FIG. 6 shows the upper surface shape such as regions (first resist region 21A, second resist region 21B) where the resist patterns 51Ax and 51Bx are formed.

  The resist 51B of the present embodiment is cured before the resist 51A to become a resist pattern 51Bx. For this reason, the resist pattern 51Bx hardly protrudes from the second resist region 21B. Further, a region (imprint shot) composed of the first resist region 21A and the second resist region 21B, a region where the resists 51A and 51B are disposed, and a region where the template Tx is pressed are substantially the same. Therefore, the region where the resist pattern 51Bx is formed and the second resist region 21B are substantially the same. In other words, the resist 51B hardly flows into a region outside the second resist region 21B (outer region 23). Therefore, it is possible to suppress the formation of the resist pattern 51Bx in the outer region 23.

  Further, since the resist 51A is harder to cure than the resist 51B, it spreads over the first resist region 21A in a short time. The resist 51A is filled in the template pattern in a short time. Furthermore, since the resist 51A is disposed on the inner side of the resist 51B, it does not protrude outside the first resist region 21A.

  Thus, the region where the resists 51A and 51B are disposed (resist placement region) and the region where the resist patterns 51Ax and 51Bx are formed (resist pattern formation region) are substantially the same.

  FIG. 7 is a diagram for explaining an imprint process when one type of resist is used. FIG. 7 shows a cross-sectional view of the wafer WA, the template Ty, and the like in the imprint process. Here, a case will be described in which an imprint is executed in the second imprint shot adjacent to the first imprint shot after the imprint is executed in the first imprint shot.

  When imprinting is performed using one type of resist 55, the resist 55 is dropped on the first imprint shot on the upper surface of the wafer WA. Then, the template Ty is moved to the resist 55 side, and the template Ty is pressed against the resist 55 as shown in FIG. As a result, the resist 55 flows into the template pattern of the template Ty. At this time, the resist 55 oozes out and flows out to an area outside the area where the template Ty is pressed (outer periphery of the pattern formation area).

  After the resist 55 is filled in the template Ty for a preset time, light 50 is irradiated from the back side of the template Ty as shown in FIG. As a result, the resist 55 is cured to form a resist pattern 55x. The resist pattern 55x is also formed in a region outside the region where the template Ty is pressed. After the resist pattern 55x is formed, the template Ty is released from the resist pattern 55x.

  Thereafter, the resist 55 is dropped on the second imprint shot on the wafer WA. Then, the template Ty is moved to the resist 55 side, and the template Ty is pressed against the resist 55 as shown in FIG.

  As a result, the resist 55 flows into the template pattern of the template Ty. At this time, the resist 55 flows out to a region outside the region where the template Ty is pressed. The resist 55 that has flowed out collides with the resist pattern 55x formed by the first imprint shot. In other words, the resist 55 that has flowed out from the second imprint shot collides with the resist pattern 55x formed by the first imprint shot. Due to this collision, the film thickness of the resist 55 increases in the vicinity of the boundary between the first imprint shot and the second imprint shot. As a result, the template Ty is tilted when imprinting is executed with the second imprint shot.

  In this way, if imprinting is performed in a state where the template Ty is placed on the resist residue during imprinting in the second imprint shot, unexpected stress is applied to the template Ty. As a result, the risk of damage to the template pattern may increase.

  On the other hand, in the method using the resists 51A and 51B, the resist 51B can be prevented from oozing out (outflow) outside the pattern formation region (second resist region 21B), and the resist 51A in the pattern formation region can be prevented. , 51B can be prevented. Further, since unexpected stress is not applied to the template Tx, it is possible to prevent the template pattern from being damaged. Further, since no pre-processing or the like for the wafer WA is required, pattern formation can be easily performed.

  In the present embodiment, the case where the photocuring characteristics of the resists 51A and 51B are different from each other has been described. However, the resist 51A and the resist 51B may be resists having different characteristics. Further, the resists 51A and 51B are not limited to a photo-curing resin, and may include a thermosetting resin.

  For example, the resist 51A and the resist 51B may be resists having different resist viscosities. In this case, the resist 51B is a resist having a higher viscosity than the resist 51A. In this case, the main components of the resists 51A and 51B include a monomer having a molecular weight smaller than about 100. Furthermore, the resists 51A and 51B have, for example, at least one relationship among the following (3) to (7).

(3) The molecular weight number A3 of the monomer contained in the main component of the resist 51A and the molecular weight number B3 of the monomer contained in the main component of the resist 51A have a relationship of A3 <B3.
(4) The double bond number A4 of the monomer contained in the main component of the resist 51A and the double bond number B4 of the monomer contained in the main component of the resist 51B have a relationship of A4 <B4.
(5) The number of cyclic structures A5 of the monomer contained in the main component of the resist 51A and the number of cyclic structures B5 of the monomer contained in the main component of the resist 51B have a relationship of A5 <B5.
(6) The mass ratio A6 with respect to the total amount of additive contained in the main component of the resist 51A and the mass ratio B6 with respect to the total amount of additive contained in the main component of the resist 51A have a relationship of A6 <B6. ing.
(7) The glass transition temperature A7 of the resist 51A and the glass transition temperature B7 of the resist 51B have a relationship of A7 <B7.

  Thereby, it is possible to suppress the resist 51B from flowing out of the second resist region 21B to the outside of the second resist region 21B. Further, unfilling of the resists 51A and 51B in the pattern formation region can be prevented.

  Further, the resist 51A and the resist 51B may be resists having different water repellency (liquid repellency). In this case, the resist 51B is a resist having higher liquid repellency (contact angle) with respect to the wafer WA than the resist 51A. For example, the contact angle of the resist 51B with respect to the wafer WA is higher than a predetermined value (for example, 60 °) or is a predetermined value or more. In this case, the main components of the resists 51A and 51B include a monomer having a molecular weight smaller than about 100. Furthermore, the resists 51A and 51B have, for example, at least one relationship of (8) and (9) below.

(8) The molar ratio A8 with respect to the total amount of the surfactant in the resist 51A and the molar ratio B8 with respect to the total amount of the surfactant in the resist 51B have a relationship of A8> B8.
(9) The molar ratio A9 with respect to the total fluorine content in the resist 51A and the molar ratio B9 with respect to the total fluorine content in the resist 51B have a relationship of A9> B9.

  Thereby, it is possible to suppress the resist 51B from flowing out of the second resist region 21B to the outside of the second resist region 21B. Further, unfilling of the resists 51A and 51B in the pattern formation region can be prevented.

  Further, the resist 51A and the resist 51B may be resists having different volatility. In this case, the resist 51B is a resist having lower volatility than the resist 51A. In this case, the main components of the resists 51A and 51B include a monomer having a molecular weight smaller than about 100. Further, the resists 51A and 51B have, for example, at least one relationship of (3) to (7) and (10) below.

  (10) The functional group number A10 of the —OH functional group (hydroxyl group) of the monomer contained in the main component of the resist 51A and the functional group number B10 of the —OH functional group of the monomer contained in the main component of the resist 51B are A10 <B10 Have the relationship.

  Thereby, it is possible to suppress the resist 51B from flowing out of the second resist region 21B to the outside of the second resist region 21B. Further, unfilling of the resists 51A and 51B in the pattern formation region can be prevented.

  The characteristics of the resists 51A and 51B described above may be used in combination. For example, the resists 51A and 51B may be resists having different two or more of photocuring characteristics, resist viscosity, volatility, and liquid repellency.

  Further, the resist 51B is not limited to the entire outer periphery of the pattern formation region, and may be disposed on a part of the outer periphery. In addition, when applying the resists 51A and 51B, a dispenser capable of switching the ink jet nozzle between the resist 51A and the resist 51B may be used.

  When a semiconductor device (semiconductor integrated circuit) is manufactured, imprint processing by the imprint apparatus 101 is performed, for example, for each layer of a wafer process. Specifically, a film to be processed is formed on the wafer WA. Thereafter, the imprint apparatus 101 drops the resist 51A onto the first resist area 21A on the wafer WA, and drops the resist 51B onto the second resist area 21B on the wafer WA. The imprint apparatus 101 forms resist patterns 51Ax and 51Bx by pressing the template Tx against the resists 51A and 51B. The imprint apparatus 101 forms resist patterns 51Ax and 51Bx on all the imprint shots on the wafer WA by repeating the imprint process on all the imprint shots on the wafer WA.

  Thereafter, the film to be processed is etched using the resist patterns 51Ax and 51Bx as a mask. Thus, actual patterns corresponding to the resist patterns 51Ax and 51Bx are formed on the wafer WA. When manufacturing a semiconductor device, the above-described processing for forming a film to be processed, imprint processing on the wafer WA using the resists 51A and 51B, etching processing, and the like are repeated for each layer.

  Thus, in the first embodiment, the template pattern is formed in a state where the speed at which the resist 51B flows out of the second resist area 21B is slower than the speed at which the resist 51A flows out of the first resist area 21A. Resists 51A and 51B are filled. As a result, the resist 51B is cured faster than the resist 51A. Accordingly, it is possible to prevent unfilled defects of the resists 51A and 51B while suppressing the resists 51A and 51B from flowing out of the imprint shot. Therefore, pattern defects can be easily reduced.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG. In the second embodiment, the resist 51B is arranged in a region corresponding to the pattern layout in the imprint shot.

  FIG. 8 is a diagram for explaining a pattern formation region according to the second embodiment. Of the constituent elements in FIG. 8, constituent elements that achieve the same functions as the constituent elements shown in FIG. 6 are given the same reference numerals, and redundant descriptions are omitted.

  The upper side of FIG. 8 shows the cross-sectional shape of the resist patterns 52Ax, 52Bx and the like. Further, the lower side of FIG. 8 shows the upper surface shape such as regions (first resist region 25A, second resist region 25B) where the resist patterns 52Ax and 52Bx are formed.

  The resist pattern 52Ax is a pattern formed using the resist 51A. The resist pattern 52Bx is a pattern formed using the resist 51B. The first resist region 25A is a region where the resist 51A is dropped, and the second resist region 25B is a region where the resist 51B is dropped.

  The imprint shot (pattern formation region) includes various pattern densities, various pattern orientations, and the like. The pattern density is a ratio of the concave pattern or the convex pattern to the pattern region. The pattern directionality is information regarding the direction in which the pattern extends (such as the ratio of the pattern extending in a predetermined direction).

  In the present embodiment, the first resist region 25A and the second resist region 25B are set based on the pattern density and pattern directionality. For example, the memory area of the imprint shot is set as the first resist area 25A, and the area other than the memory area is set as the second resist area 25B.

  FIG. 8 shows a case where the first resist area 25A is a rectangular area, and four first resist areas 25A are set in the imprint shot. The second resist region 25B is a region other than the first resist region 25A in the imprint shot. Therefore, the second resist region 25B is a region obtained by combining a substantially rectangular annular region and a cross-shaped region.

  The resist 51B of the present embodiment is cured before the resist 51A to become a resist pattern 52Bx. For this reason, the resist pattern 52Bx hardly protrudes from the second resist region 25B. In addition, a region (imprint shot) including the first resist region 25A and the second resist region 25B, a region where the resists 51A and 51B are arranged, and a region where the template Tx is pressed are substantially the same. Therefore, the region where the resist pattern 52Bx is formed and the second resist region 25B are substantially the same. In other words, the resist 51B hardly flows into a region outside the second resist region 25B (outer region 23). Therefore, it is possible to suppress the formation of the resist pattern 52Bx in the outer region 23.

  Thus, the region where the resists 51A and 51B are disposed (resist placement region) and the region where the resist patterns 52Ax and 52Bx are formed (resist pattern formation region) are substantially the same.

  As described above, according to the second embodiment, in a state where the speed at which the resist 51B flows out of the second resist area 25B is slower than the speed at which the resist 51A flows out of the first resist area 25A, the template The pattern is filled with resists 51A and 51B. As a result, the resist 51B is cured faster than the resist 51A. Accordingly, it is possible to prevent unfilled defects of the resists 51A and 51B while suppressing the resists 51A and 51B from flowing out of the imprint shot. Therefore, it is possible to easily reduce pattern defects as in the first embodiment.

(Third embodiment)
Next, a third embodiment will be described with reference to FIG. In the third embodiment, a resist having smaller droplets than the first resist region 21A is dropped on the second resist region 21B.

  FIG. 9 is a diagram for explaining the resist droplet size according to the third embodiment. FIG. 9 shows a top view of the imprint shot. A resist 53A is dropped on the first resist region 21A. A resist 53B is dropped on the second resist region 21B.

  The resists 53A and 53B are, for example, resins having photocurability and the like, like the resists 51A and 51B. The resists 53A and 53B are resists having the same components. The resist 53B has a smaller drop volume (volume of inkjet droplets) than the resist 53A.

  Therefore, the resist 53B is less likely to spread on the wafer WA than the resist 53A. For this reason, in the present embodiment, it is possible to prevent the resist 53B from flowing out of the second resist region 21B to the outside of the second resist region 21B.

  For dropping the resists 53A and 53B, for example, as described in the first embodiment, different droplet dropping devices (dispensers) 8A and 8B are used. Note that the resist 53B is not limited to the entire outer periphery of the pattern formation region, and may be disposed on a part of the outer periphery. Further, when applying the resists 53A and 53B, a dispenser capable of switching the ink jet nozzle between the resist 53A and the resist 53B may be used.

  Further, the resists 53A and 53B may be dropped on the wafer WA by one droplet dropping device having one inkjet nozzle. In this case, the drop dropping device adjusts the drop volumes of the resists 53A and 53B by dropping one to a plurality of droplets at one dropping position. For example, the droplet dropping device drops N (N is a natural number) resists at one dropping position with respect to the second resist region 21B, and uses the N drops of resist as the resist 53B. Further, the droplet dropping device drops M (M is a natural number larger than N) drops of resist at one dropping position with respect to the first resist region 21A, and the resist for the M drops is used as a resist 53A. .

  The resists 53A and 53B may have the same characteristic difference as the resists 51A and 51B. For example, the resist 53A and the resist 53B may be resists that differ in at least one of photocuring characteristics, resist viscosity, volatility, and liquid repellency.

  Thus, according to the third embodiment, the droplet volume of the resist 53B is smaller than the droplet volume of the resist 53A. For this reason, the speed at which the resist 53B flows out of the second resist area 21B is slower than the speed at which the resist 53A flows out of the first resist area 21A. In this state, the template pattern is filled with the resists 53A and 53B, so that the resist 53B is cured faster than the resist 53A, thereby preventing the resists 53A and 53B from flowing out of the imprint shot. Further, unfilled defects of the resists 53A and 53B can be prevented. Therefore, it is possible to easily reduce pattern defects as in the first embodiment.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  8A, 8B ... Droplet dropping device, 10 ... Light source, 20 ... Controller, 21A, 25A ... First resist region, 21B, 25B ... Second resist region, 23 ... Outer region, 41A, 41B ... Head, 50 ... Light, 51A , 51B, 53A, 53B, 55 ... resist, 51Ax, 51Bx, 55x ... resist pattern, 101 ... imprint apparatus, Tx, Ty ... template, WA ... wafer.

Claims (5)

A first dropping step of dropping a first resist having a first characteristic in a first region of an imprint shot on a substrate;
A second dropping step of dropping a second resist in a second region outside the first region of the imprint shot;
Contacting the first and second resists with a template pattern formed on a template;
While filling the first and second resist to the template pattern, and the curing step of pre-Symbol faster curing the second resist than the first resist, curing the first and second resist,
Only including,
The first resist and the second resist have different components.
The pattern formation method characterized by the above-mentioned. The first and second resists include a photocurable resin,
When curing the first and second resists, the first and second resists are irradiated with light,
The second resist is a resist that begins to cure with a smaller dose than the first resist.
The pattern forming method according to claim 1. While curing the second resist while filling the template pattern with the first and second resists,
After the filling of the second resist into the template pattern and the complete curing of the second resist are completed, the curing of the first resist is started.
The pattern forming method according to claim 2. The second resist is a resist having a higher viscosity than the first resist.
The pattern forming method according to claim 1. The second resist is a resist having higher liquid repellency to the substrate than the first resist.
The pattern forming method according to claim 1.

Images