Droplet ejection device

Abstract

To provide a droplet discharge device capable of meeting desired discharge conditions within the constraints of a storage area.SOLUTION: A droplet discharge device includes discharge means including a first nozzle capable of discharging one of the conditions of a first group of discharge conditions and a second nozzle capable of discharging one of the conditions of a second group of discharge conditions, storage means for storing the first and second groups of discharge conditions, and control means for controlling the discharge means on the basis of the discharge conditions stored in the storage means. When the discharge conditions of a droplet are not included in the group of discharge conditions discharged by the first nozzle, a process for reassigning the droplet to be discharged by the second nozzle is included.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a droplet discharge device.

Background Art

[0002] In response to the miniaturization of semiconductor devices, MEMS (Micro Electro Mechanical Systems) and other components, in addition to conventional photolithography technologies, there is a microfabrication technology that molds uncured resin on a substrate and forms a resin pattern on the substrate. This technology, also called imprint technology, can form fine structures on the order of several nanometers on a substrate. One of the imprint technologies is the photo-curing method. A dispenser in an imprint apparatus adopting the above technology requires high accuracy in the discharge speed and discharge amount of resin applied to a substrate. Note that a deviation in discharge speed leads to a deviation in the position where the resin adheres to the substrate. If the discharge position or discharge amount deviates, uneven thickness will occur in the resin applied in the shot, which deteriorates the filling property of the resin into the mold and may cause defects in the resin pattern.

[0003] In response to this, a technology for suppressing deviations in discharge speed and discharge amount by selecting discharge conditions from a plurality of discharge conditions according to the discharge interval for discharging resin onto a substrate has been disclosed (Patent Document 1).

Prior Art Literature

Patent Literature

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, due to limitations such as the amount of hardware memory in the liquid dispensing device, there is a limit to the number of dispensing conditions that can be used in a single dispensing (dispensing scan). Therefore, with conventional technology, it may not be possible to apply all droplets with the desired dispensing conditions. Furthermore, if the amount of memory is increased to store all the desired dispensing conditions, the data transfer time to each nozzle will increase, leading to a decrease in the device's throughput.

[0006] Therefore, the present invention aims to provide a droplet dispensing device that can satisfy desired dispensing conditions within the constraints of memory space. [Means for solving the problem]

[0007] To achieve this objective, a droplet dispensing device as one aspect of the present invention comprises a dispensing means including a first nozzle capable of dispensing any of the conditions of a first dispensing condition group and a second nozzle capable of dispensing any of the conditions of a second dispensing condition group; a storage means for storing the first and second dispensing condition groups; and a control means for controlling the dispensing means based on the dispensing conditions stored in the storage means, wherein if the dispensing conditions for a droplet are not included in the dispensing condition group for dispensing by the first nozzle, the device has a step of reassigning the droplet to be dispensed to be dispensed by the second nozzle. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a droplet dispensing device that can satisfy desired dispensing conditions within the constraints of the memory area. [Brief explanation of the drawing]

[0009] [Figure 1] This figure shows an imprinting device according to the first embodiment. [Figure 2] This diagram shows the coating pattern applied to the shot area. [Figure 3] This is a diagram showing the discharge conditions. [Figure 4] This diagram illustrates the process of applying imprint material while moving the circuit board stage. [Figure 5] This is a diagram showing the nozzle surface of the dispenser. [Figure 6] This diagram shows the group of discharge conditions. [Figure 7] This is a flowchart of the method for reassigning the nozzles used in the first embodiment. [Figure 8] This diagram shows the reassignment of nozzles for use. [Figure 9] This diagram shows the reassignment of nozzles for use. [Figure 10] This is a diagram illustrating the imprint operation of the first embodiment. [Figure 11] This diagram shows the reassignment of nozzles for use. [Figure 12] This diagram shows the division of the shot area into sets. [Modes for carrying out the invention]

[0010] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0011] <First Embodiment> Figure 1 shows the imprint apparatus IMP of this embodiment. The imprint apparatus IMP of this embodiment includes a substrate chuck 101 (substrate holding unit) for holding a substrate W, and a substrate stage 102 for supporting and moving the substrate chuck 101. It also includes a mold chuck 103 (mold holding unit) for holding a mold M on which a pattern P is formed, and a mold stage 104 (mold driving unit) for supporting and moving the mold chuck 103. It also includes a supply unit D (dispenser (liquid dispensing device)) for supplying imprint material R onto the substrate W. Furthermore, it includes a control unit CNT for controlling the imprint operation, a console unit CONS for generating an operation screen, a monitor 112 for displaying the operation screen, and an input device 113 such as a keyboard or mouse. The control unit CNT has a memory for storing and referencing specific data.

[0012] In the present embodiment, a case will be described where an ultraviolet curable resin that cures when irradiated with ultraviolet rays is used as the imprint material R, but the imprint material R may be a thermoplastic or thermosetting resin.

[0013] Figure 2 shows an application pattern RP managed by the console unit CONS. The application pattern RP includes, for each droplet when supplying the imprint material (droplet) onto the substrate W, the ejection target coordinates, ejection conditions (C11, C12, ..., C21, C22, ...), and scanning pass information for ejection. As shown in Figure 3, the ejection conditions (C11, C12, ...) include information such as the ejection volume of each droplet and the shift amount of the ejection landing position (target). However, it is not necessary to include all of these, and information other than these may also be included.

[0014] The control unit CNT controls the substrate stage 102 and the dispenser D so that the imprint material R is supplied onto the substrate W at the positions described in the application pattern RP. Specifically, as shown in Figure 4, the control unit CNT ejects the imprint material R to be ejected in a first scanning pass from a plurality of nozzles N arranged in the dispenser D while scanning (moving) the substrate stage 102 in the direction of arrow 201; subsequently, the control unit CNT drives the substrate stage 102 in the direction opposite to arrow 201 and ejects the imprint material R to be ejected in a second scanning pass, thereby forming the application pattern RP on the substrate W. Here, an example where the number of scans for forming the application pattern RP is two has been given, but the number of scans may be only one, or the imprint material R may be ejected while performing three or more scans.

[0015] By pressing (stamping) the mold M against the substrate W supplied with the imprint material R, the imprint material R is filled into the pattern P of the mold M.

[0016] A surface on the opposite side of the center pattern P surface of the mold chuck 103 has a recess larger than the area of the pattern P, and is sealed by the mold M and a seal glass (not shown). A pressure control unit (not shown) is connected to this sealed space (cavity part), and the pressure in the sealed space can be controlled. During imprinting, the pressure in the cavity part is increased to deform the mold M into a convex shape, thereby suppressing air bubbles from being trapped between the substrate W and the mold M during imprinting. When the substrate W and the mold M come into contact, the pressure in the cavity part is restored so that the substrate W and the mold M come into complete contact.

[0017] The imprint apparatus IMP further includes an alignment scope 105 fixed to a mold stage 104 that detects an alignment mark formed on the substrate W (substrate-side mark 106) and an alignment mark formed on the mold M (mold-side mark 107). The alignment scope 105 detects the substrate-side mark 106 formed in a shot area on the substrate W and the mold-side mark 107 formed in the pattern P of the mold M. A calculation unit CAL of a control unit CNT obtains the relative positional deviation between the mold M and the substrate W from the detection results of the substrate-side mark 106 and the mold-side mark 107 detected by the alignment scope 105.

[0018] The control unit CNT drives the substrate stage 102 and the mold stage 104 based on the obtained result of the relative positional deviation to correct the relative positional deviation between the mold M and the substrate W. The relative positional deviation is not limited to shift components, and also includes errors in magnification and rotation components. The shape of the pattern P (pattern area) of the mold M can be corrected according to the shot area formed on the substrate W. As a detection method for the substrate-side mark 106 and the mold-side mark 107, an interference signal such as a moiré signal reflecting the relative positions of the two marks can be used. Alternatively, the relative positions of the two marks may be obtained by detecting images of the respective marks.

[0019] 110 is a mirror, 108 is a light source that emits exposure light (ultraviolet light), and 109 is a detection light source that emits detection light. Mirror 110 is a dichroic mirror and has the property of reflecting exposure light and transmitting detection light. The exposure light from light source 108 is reflected by mirror 110 and irradiated onto the imprint material R, curing the imprint material R. As a result, the pattern P of mold M is transferred onto the substrate W.

[0020] The detection light from the detection light source 109 passes through the mirror 110, the mold stage 104, and the mold chuck 103, illuminating the shot area on the substrate W. The light illuminating the shot area is reflected from the surface of the substrate W and the pattern surface of the mold M, and the reflected light from the substrate W and the reflected light from the mold M are detected as detection light by the imaging unit 111. The detection light detected by the imaging unit 111 is displayed on the monitor 112, allowing the operator to observe the imprint process.

[0021] Figure 5 shows the nozzle surface of dispenser D as viewed from below the device. Nozzle N consists of multiple nozzles N1, N2, N3, ... Here, dispenser D consisting of one row of nozzles is shown as an example, but it may also consist of multiple rows of nozzles. By aligning the target coordinates of the droplet discharge of the coating pattern RP with the distance between these nozzles N1, N2, N3, ..., the imprint material R can be applied with a small number of scan passes.

[0022] Figure 6 shows the discharge condition set. The set of discharge conditions C11, C12, C13, ... used by nozzle N1 when forming the coating pattern RP constitutes the discharge condition set for nozzle N1. This discharge condition set is stored in the memory of the control unit CNT for each nozzle N1, N2, N3, ... The number of discharge conditions that can be stored per nozzle is limited according to the memory capacity, and the limit (upper limit) of the number of discharge conditions is determined. [Examples]

[0023] The nozzle reassignment process in this embodiment will be explained with reference to Figure 7. The series of processes shown below are controlled by the control unit CNT of the imprint device IMP. The memory of the control unit CNT pre-stores data such as the shot numbers and positions on the substrate for multiple shot areas set on the substrate W.

[0024] In step S301, the coating pattern RP is read, and a nozzle to be used for ejecting each droplet is assigned. In the configuration shown in Figure 4, typically the same nozzle is assigned to droplets with the same Y-coordinate at the target ejection position. Figure 8(a) shows an example of nozzle assignment to a coating pattern. Nozzle N1 is assigned to the first row of droplets R1001, which have the same Y-coordinate. Nozzle N1 is also assigned to the second row of droplets R1002. (The first row of droplets R1001 and the second row of droplets R1002 can be assigned the same nozzle because they have different scan paths.) Droplet groups from the third row onward can be assigned using the same approach.

[0025] In step S302, based on the results of assigning nozzles to be used in step S301, it is checked whether the discharge conditions for all droplets are included in the set of discharge conditions for each nozzle being used. For example, the number of droplet discharge conditions assigned to each nozzle can be counted and it can be determined whether this number is within the limit.

[0026] If the result of the determination in step S302 is No, then in step S303, the nozzles used for droplet ejection are reassigned. For example, in the coating pattern shown in Figure 8(a), if the number of ejection conditions used in the first scanning pass does not exceed the limit, but the number of ejection conditions used in nozzle N1 exceeds the limit when the second scanning pass is included, then the nozzles are reassigned as shown in Figure 8(b). First, the nozzles used in the first scanning pass are left as they are. Next, the nozzles used in the second scanning pass are shifted down one by one. That is, the nozzle used for ejecting droplet group L1002 is reassigned to nozzle N2, and the nozzle used for ejecting droplet group L1004 is reassigned to nozzle N4. This reassignment of nozzles is performed for all droplet groups.

[0027] This process terminates the reassignment process if the number of discharge conditions used by each nozzle falls within the limit. If the number of conditions does not fall within the limit, the system searches for available nozzles by shifting them up one position at a time, down two positions at a time, up two positions at a time, and so on, and reassigns the nozzles to be used.

[0028] Finally, in step S304, the nozzle reassignment process is completed by setting the reassigned discharge condition set for each nozzle. Note that if the discharge condition set has already been set, step S304 may be omitted.

[0029] Furthermore, if the nozzle assignment is changed as described above, the target ejection position will shift by the difference in the Y coordinate of the nozzle being used. Therefore, by also shifting the Y position of the substrate stage 102 during scanning, it is possible to apply droplets to the target position according to the coating pattern RP.

[0030] The following method can also be used for the reassignment process in step S303. In the coating pattern shown in Figure 9(a), if the number of ejection conditions used in the first scan pass exceeds the limit, an additional scan pass is performed. Figure 9(b) shows the coating pattern after the addition of the scan pass. First, droplet group R2001 is divided into droplet group R2101 and droplet group R2102 so that the number of ejection conditions used in the first scan pass is within the limit. One droplet group R2101 is assigned the same nozzles as R2001. The other droplet group R2102 is assigned nozzles to droplet group R2101 as it will be ejected in the second scan pass. Due to the limit on the number of ejection conditions, the nozzles used to eject droplet group R2102 in the second scan pass must be different from the nozzles used to eject droplet group R2101 in the first scan pass.

[0031] The reassignment method is the same as explained in Figure 8(b), by shifting the nozzle up and down to search. Note that Figure 9 shows an example of changing a coating pattern with one scan pass to a coating pattern with two scan passes, but a coating pattern with one scan pass can be changed to a coating pattern with three or more scan passes, and a coating pattern with two or more scan passes can be changed to a coating pattern with three or more scan passes.

[0032] Figures 8 and 9 show an example of droplet ejection in a single scan for a single shot area, but as shown in Figures 10(a), 10(b), and 10(c), droplet ejection can also be performed in a single scan for multiple shot areas 120, 121, and 122. Figure 10(a) is a view of the substrate W from the +Z direction. When ejection is performed in a single scan for a set of multiple shot areas 120, 121, and 122 as shown in Figure 10, the control unit CNT moves the substrate stage 102 holding the substrate W so that shot area 122 passes through the trajectory 202 and reaches the coating start position 203. When shot area 122 reaches the coating start position 203, the control unit CNT moves the substrate stage 102 so that shot area 122 passes through the trajectory 204, as shown in Figure 10(b).

[0033] In this process, the control unit CNT applies the imprint material R from the dispenser D to each of the shot regions 120, 121, and 122 according to the application pattern RP indicating the target position of the droplets of the imprint material R in each of the shot regions 120, 121, and 122. This ensures that droplets of the imprint material R are supplied (placed) at the target positions in each of the shot regions 120, 121, and 122. Once the application of the imprint material R to the shot regions 120, 121, and 122 is complete, the control unit CNT moves the substrate stage 102 so that the shot region 120 is below the mold M via the track 205, as shown in Figure 10(c). The control unit CNT then controls the substrate stage 102, mold stage 104, light source 108, etc., as described above, to form patterns of the imprint material R in each of the shot regions 120, 121, and 122. In this case as well, the nozzle reassignment process described earlier can be applied.

[0034] Figure 11 shows the coating pattern and assigned nozzles when dispensing to multiple shot regions 120, 121, and 122 in a single scan. In the coating pattern shown in Figure 11(a), if the number of dispensing conditions used in the first scan pass exceeds the limit, a method is used in which the assigned nozzle is changed for each shot region within the same scan pass.

[0035] Figure 11(b) shows an example of reassigning nozzles used in shot area 122. First, we try changing the nozzle used for dispensing in one of the multiple shot areas. The droplet group R3001 is divided into droplet group R3101 in shot areas 120 and 121 and droplet group R3102 in shot area 122. The nozzle used for dispensing droplet group R3101 is the same as that used for droplet group R3001 before division, and the nozzle used for dispensing droplet group R3102 is reassigned following the method described above. If this brings the number of dispensing conditions for each nozzle within the limit, the reassignment process is terminated. If it does not bring the number of dispensing conditions within the limit, the droplet group can be further divided and the reassignment of the nozzles used can be repeated.

[0036] Additionally, scanning passes can be added when reassigning nozzles. Figure 11(c) shows an example of adding scanning passes and reassigning nozzles. If attempting to eject multiple shot regions 120, 121, and 122 in the first scanning pass would exceed the limit on the number of ejection conditions, the droplet group R3201, which has an ejection condition within the limit, is divided into two groups: droplet group R3201 and the remaining droplet group R3202. Droplet group R3201 is ejected in the first scanning pass, and the nozzles used remain the same as before the division. Droplet group R3202 is ejected in the second scanning pass, and the nozzles used can be reassigned following the method described above.

[0037] Furthermore, the number of ejection conditions can be kept within the limit by dividing the set of shot regions that eject droplets in a single scan pass. Figure 12 shows an example of dividing a set of shot regions. G4001 is a set of shot regions that eject droplets to shot regions 120, 121, and 122 in a single scan. If the number of ejection conditions exceeds the limit when ejecting these shot regions in a single scan, the set G4001 is divided by removing some of the shot regions from the set. Figure 12(b) shows an example of dividing shot region 120 into set G4101 and shot regions 121 and 122 into set G4102. If the number of ejection conditions used in set G4101 is within the limit, and the number of ejection conditions in G4102 is also within the limit, the reassignment process is terminated. If either set does not fall within the limit, further reassignment is performed using the method shown in Figure 11. If it still does not fall within the limit, the set is divided again. By reassigning the nozzles used in this way, it becomes possible to perform dispensing under the desired dispensing conditions.

[0038] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of its essence. [Explanation of Symbols]

[0039] CNT Control Unit D Dispenser N1, N2, N3, ... Nozzles R Imprint Material RP coating pattern C11, C12, C13... Discharge conditions

Claims

1. Discharge means including a first nozzle capable of discharging any of the conditions in a first group of discharge conditions, and a second nozzle capable of discharging any of the conditions in a second group of discharge conditions, A storage means for storing the first and second discharge condition groups, A control means that controls the discharge means based on the discharge conditions stored in the storage means. Equipped with, A droplet dispensing device characterized by having a step of reassigning a droplet to be dispensed by the second nozzle if the droplet dispensing conditions are not included in the group of dispensing conditions for dispensing by the first nozzle.

2. The droplet dispensing device according to claim 1, characterized in that the reassignment step includes a step of increasing the number of scanning passes.

3. The droplet dispensing device according to claim 1 or 2, characterized in that the reassignment step is applied in a coating pattern that dispenses droplets to multiple shot areas in a single scan.

4. The droplet ejection apparatus according to claim 3, characterized by including a step of dividing a set of shot regions that eject droplets in a single scan into a plurality of sets.

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