JP4745177B2 - Method and apparatus for detecting print pressure in micro contact printing - Google Patents

Description

  The present invention relates to a microcontact print, in which a stamp and a workpiece are paralleled, and the stamp is replenished with a chemical solution as a transfer agent, and the workpiece is brought relatively close to each other at a required contact pressure to bring the chemical solution into contact with the workpiece. The present invention relates to a printing pressure detection method and apparatus for managing a contact pressure for transferring to a sheet.

  A master plate such as a resist pattern is cast in PDMS (polydimethylsiloxane), the PDMS mold is used as a mold mold, an organic polymer solution containing thiol is applied, and a metal film on the substrate is stamped to form a self-assembled film. The forming technique is known as a microcontact printing method. This method is attracting attention as a technique for creating an ultrafine circuit pattern relatively easily. However, this method is conventionally carried out almost manually and has not yet reached an industrial stage.

  In order to perform microcontact printing, for example, when ink is replenished from the ink holder base to the stamp, or when ink is transferred from the stamp to the workpiece, a contact (contact) process is performed. A technique for industrially controlling or managing pressure (contact thrust) has not been established. Therefore, with the conventional method, it is difficult to mass-produce micro contact prints that maintain a constant contact pressure accurately and maintain a constant accuracy. This means that the transfer method due to the viscosity of the material such as ink and the transfer property due to the adhesion between the stamp and the work cannot always be maintained in the best state by the conventional method.

  The reason why it is difficult to control the contact pressure in order to transfer a chemical solution to a workpiece in micro contact printing is that the pattern to be transferred there is a nanometer size. Specifically, since it is an extremely small size of 1/1000 of 1 micron, for example, in order to draw a uniform line, the accuracy of the nanometer level is required for the parallelism, the moving amount, etc. It is not easy to implement this. In some devices, the load was detected by the current value monitor of the servo motor, and the applied pressure was controlled. However, it is difficult to eliminate the friction of the gear reduction mechanism and the sliding resistance of the linear guide, and because the resolution of motor torque control by current value is insufficient, accurate pressure control is extremely difficult. Met.

  Some proposals have been made in the microcontact printing technology. For example, Japanese Patent Application Laid-Open No. 2005-129791 relates to the application of the present applicant, but does not have contents intended for mass production. . Japanese Patent Application Laid-Open No. 2006-140493 relates to a soft lithography stamp including microcontact printing and a method for manufacturing the stamp, but does not disclose a specific mass production method.

JP 2005-129791 A JP 2006-140493 A

  The present invention has been made paying attention to the above points, and the problem is to accurately manage the contact pressure of the stamp against the workpiece in the microcontact printing method. Another object of the present invention is to accurately transfer a chemical solution such as ink from a stamp onto a workpiece in the micro contact printing method, so that the micro contact printing method can be industrially implemented.

In order to solve the above-described problems, the present invention is such that the stamp and the workpiece are paralleled, and the stamp is filled with a chemical as a transfer agent, the stamp and the workpiece are relatively brought close to each other, and a required contact pressure is obtained. In order to transfer the chemical solution to the workpiece by contacting with, the means for pressurizing the initial pressure to the stamp holder holding the stamp moves as the workpiece rises as a method of controlling the contact pressure Pressurization means including pressurization with possible weights , a predetermined load is applied to the stamp holder side in advance to detect the value as an initial pressure, and the work placed below the stamp is applied to the stamp The contact pressure is applied, the contact pressure is detected, and the difference between the contact pressure and the initial pressure applied to the side holding the stamp is printed pressure. In which it took method means that detected.

  In the print pressure detection method according to the present invention, the stamp is brought into contact with the workpiece at a required contact pressure and the process of transferring the chemical solution is handled. Therefore, the stamp and the workpiece are parallelized, and the stamp is used as a transfer agent. The chemical solution is in a stage where it can be replenished. Therefore, if the stamp and the work are brought into contact with each other, it is assumed that the target stamp can be executed.

  In the print pressure detection method of the present invention, first, a predetermined load is applied in advance to the side holding the stamp, and the value is detected as the initial pressure. Thereafter, the workpiece is brought close to the stamp, and further a contact pressure is applied, the contact pressure is detected, and a difference between the initial pressure and the contact pressure is detected as a print pressure. Therefore, the condition of initial pressure> contact pressure is necessary. Here, “detecting” the pressure does not necessarily mean detecting the pressure as a numerical value. For example, if it is possible to grasp that a specific pressure such as initial pressure is applied, and then understand when another pressure such as contact pressure is applied, then the difference between the initial pressure and the contact pressure can be grasped. That's enough.

  The same detection means may be used as the initial pressure detection means and the contact pressure detection means, or separate detection means may be used. If the same sensor means is used as the initial pressure detecting means and the contact pressure detecting means, the mechanism is rationalized and it is economically advantageous. In the printing pressure detection method of the present invention, the detected pressure is accurate because it is completely independent from elements other than the initial pressure at the stage of detecting the initial pressure. When the same sensor means is used, the contact pressure is detected as including the initial pressure, and the target print pressure is obtained by subtracting the contact pressure from the initial pressure.

  In a test performed in the course of developing the print pressure detection method according to the present invention, a method of providing a pressure detection means on the side of the workpiece that contacts the stamp was also considered. However, in that case, there was a problem with the work rising. For example, when taking the method of raising the workpiece with a linear motion guide, the sliding resistance of the linear motion guide becomes a load on the detection means, and when the method of providing pressure detection means at the lower part of the workpiece is adopted, It has been found that there is a problem that the detection means picks up the acceleration generated by the moving operation to be brought into contact. However, if configured as in the present invention, the target value can be obtained accurately without causing the above problems.

An apparatus for carrying out the method of the present invention includes a stamp holder that holds a stamp on the lower surface, and a stamp holder support that supports the stamp holder at the periphery, and contacts and contacts the stamp holder. A plurality of sensor means for detecting pressure are arranged between the stamp holder and the stamp holder support base, and the stamp holder is attached to the sensor means on the stamp holder support base on which the plurality of sensor means are arranged. In order to pressurize in advance, a pressurizing mechanism consisting of pressurizing means including pressurization with a weight that can move according to the amount of workpiece lift is equipped, and an elevating mechanism that raises the workpiece relative to the stamp is placed below the stamp It is arranged and the contact pressure is applied to the stamp by the work by the operation of the lifting mechanism, and the set of sensors described above The configuration detects the initial pressure applied to the side holding the stamp by the step, detects the contact pressure against the stamp by the workpiece, and detects the difference between the initial pressure and the contact pressure as the print pressure. It shall have.

  With this configuration, the stamp holder that holds the stamp on the lower surface is positioned relatively higher, and the workpiece and the lifting mechanism that raises the workpiece relative to the stamp are positioned lower than the stamp. A load applied to the side holding the stamp by arranging a plurality of sensor means for detecting the contact pressure by contacting the stamp holder between the stamp holder and the stamp holder support base. Is detected as the initial pressure.

  In the present invention, the proximity movement of the stamp and the workpiece can be realized by fixing the height of the workpiece and lowering the entire stamp holder. In this case, as described above, There arises a problem that the pressure detecting means picks up the acceleration for moving. That is, when an object with mass is in contact with the pressure detection unit, the inertia of the member cannot be ignored if it is moved.

  The configuration of claim 2 does not limit the state of the stamp and the stamp holder that holds the stamp on the lower surface. Therefore, it includes a case where the stamp and the stamp holder holding the stamp on the lower surface are simply placed on the stamp holder support. In this case, the load of the stamp and the stamp holder holding the stamp on the lower surface is the initial load and the upper limit of the contact pressure.

  In the present invention, a fixed load is applied in advance by fixing the stamp and the stamp holder holding the stamp on the lower surface by the fixing means. In this way, an arbitrary initial load can be obtained. it can. An example of a specific configuration in which a constant load is applied in advance is to equip a stamp holder support base on which a plurality of sensor means are arranged with a pressurizing mechanism for pre-pressing the stamp holder against the sensor means. .

  The pressurizing mechanism uses a fixed claw that is rotatably provided on the stamp holder support. One fixed claw is provided for each sensor means, and the position of the sensor means off-axis is determined by the rotation of each fixed claw. It can comprise so that it may be arrange | positioned on an axis | shaft (invention of Claim 3). As a pressurizing mechanism for applying a constant load in advance, there are, for example, a weight, a clamp mechanism, a kind of plunger, and the like in addition to the fixed claw.

  It is desirable that the stamp holder has a circular planar shape and that three load cells are arranged at equiangular intervals on the concentric circles (the invention according to claim 4). That is, if the stamp holder has a circular plane shape, the apparatus has an excellent weight balance.

  When referring to the hardware elements used in the print pressure detecting device in the microcontact printing according to the present invention, first, the load cell is preferable as a sensor means for pressure detection. The load cell in this case is typically a strain gauge pressure sensor. In addition, it is desirable to use a torque control motor with a speed limiting function as the Z-axis servo motor for the lifting mechanism that raises the workpiece relative to the stamp. This type of motor combines the control of rotational speed, torque, and position. It has a function to perform automatically.

  Since the present invention is configured and operates as described above, in the microcontact printing method, there is an effect that the contact pressure of the stamp with respect to the workpiece can be accurately managed. Further, according to the present invention, in the micro contact printing method, the difference between the initial pressure applied to the side holding the stamp and the contact pressure can be accurately detected as the printing pressure. A chemical solution such as ink can be accurately transferred to the workpiece, and the microcontact printing method can be industrially implemented. That is, according to the present invention, the influence of the stamp shape change at the time of contact between the stamp and the workpiece is reduced, the transfer characteristic is improved by the viscosity of the chemical liquid such as ink transferred to the workpiece, and the adhesion between the stamp and the workpiece is the best. Thus, the transfer characteristics can be improved, and the transfer characteristics can be improved by shortening the transfer time by automatic control.

Method 1
Hereinafter, a print pressure detection method in microcontact printing according to the present invention will be described in more detail with reference to the illustrated embodiment. FIG. 1 shows an example of a printing pressure detection method 1 of the present invention. A stamp 11 having a mold and a stamp holder 12 having a circular plane shape holding the stamp 11 are placed on a stamp holder support base 13. It is an example of the structure arrange | positioned . The stamp holder 12 has a rectangular window 12a at the center. In order to apply a predetermined load in advance, a plurality of weights 18 are disposed on the stamp holder 12. In the example of this method 1, the weight 18 is attached to the shaft 18a in a replaceable manner, and the load applied in advance in the present invention can be changed. This example should be understood as providing a load that can be changed, rather than an example of a specific structure.

  In FIG. 1, reference numeral 14 denotes a sensor means having a load cell, that is, a contact 14a for detecting pressure, which is arranged on a stamp holder support 13 as a set of three, and supports the stamp holder 11 in contact with its lower surface. is doing. Reference numeral 15 denotes a chemical such as ink, which is transferred to the work 21. Reference numeral 17 denotes a photomask formed of a transparent plate material for microscopic observation, and the stamp 11 is fixed to this lower surface using a stopper as in the prior art. The workpiece 21 is fixed to the upper surface of the workpiece table 22, and the workpiece table 22 is disposed on the top of the base 25 of the XYZΘ alignment mechanism 24 via the parallel adjustment mechanism 23. The Z-axis alignment mechanism of the XYZΘ alignment mechanism 24 is a lifting mechanism. It is desirable to use a servo motor of a type called a torque control motor with a speed limiting function for the elevating mechanism of this Z-axis alignment mechanism. This type of motor can perform control of rotation speed, torque, and position in combination, and is rotated by a signal generated from a control unit based on contact pressure data detected by the sensor means 14 described above. And stop when the set contact pressure is reached, enabling precise pressure management.

  In Example 1 of the print pressure detection method of the present invention configured as described above, the stamp 11 and the workpiece 21 are parallelized by the parallel adjustment mechanism 23, and the chemical solution 15 is replenished to the stamp 11 as a transfer agent. The sensor means 14 first detects the sum of the load of the stamp 11 and the stamp holder 12 holding the stamp 11 on the lower surface, the photomask 17 and the weight 18 as an initial pressure. Next, the Z-axis alignment mechanism of the XYZΘ alignment mechanism 24 is operated to bring the workpiece 21 into contact with the stamp 11. Since the contact pressure of the workpiece 21 with respect to the stamp 11 is detected by the sensor means 14, the target print pressure can be obtained by calculating the difference between the initial pressure and the contact pressure.

Method 2
FIG. 2 shows an example of the print pressure detection method 2 of the present invention. Example 1 in which the stamp 11 and the stamp holder 12 holding the stamp 11 on the lower surface are simply placed on the stamp holder support 13. In addition to the configuration described above, an example in which a pressurizing mechanism for pre-pressing the stamp holder 12 against the sensor means 14 is provided. As the pressurizing mechanism, a fixed claw 16 provided rotatably on the stamp holder support base 13 is used. One fixed claw 16 is provided on each sensor means 14, and the sensor means is detected by the rotation of each fixed claw 16. It is comprised so that it may arrange | position from the position off-axis on the axis | shaft of 14 contactors 14a.

  Since the other structure in the method 2 is common to the case of the method 1, the reference numerals are used and a specific description is omitted. Also in the case of the method 2, the stamp 11 and the workpiece 21 are parallelized by the parallel adjusting mechanism 23. Then, the stamp 11 is preliminarily pressed against the sensor means 14 by the pressurizing mechanism with respect to the stamp 11 in which the chemical solution 15 is replenished as a transfer agent. The total of the load applied to the stamp holder 12 holding the stamp 11 on the lower surface is detected by the sensor means 14 as the initial pressure.

  Also in the case of the method 2, the predetermined load applied in the pressurizing mechanism can be set freely, and the value can be managed easily as in the case of the method 1. After detecting the initial pressure, the Z-axis alignment mechanism of the XYZΘ alignment mechanism 24 is operated, and the workpiece 21 is brought into contact with the stamp 11 by the torque control motor with a speed limiting function. Since the contact pressure of the workpiece 21 with respect to the stamp 11 is detected by the sensor means 14, the target print pressure can be obtained by calculating the difference between the initial pressure and the contact pressure. Therefore, in the example of the method 2, the initial pressure can be set to a much larger value than in the example of the method 1, and the range that can be set as the print pressure is remarkably wide.

Further, the print pressure detecting device in the micro contact printing according to the present invention will be described in more detail. 3 is a plan view showing an example of a microcontact printing apparatus 30 to which the printing pressure detection apparatus of the present invention is applied, FIG. 4 is a front view thereof, and FIG. 6 is a schematic explanatory view of the apparatus 30. In addition, the code | symbol already used by description in the apparatus structure of the method 1 and 2 is used also in description of this apparatus. In other words, the same reference numeral indicates a common configuration in all the drawings.

  As shown in the drawings, the apparatus 30 includes a print station 31 and an ink replenishment station 32 on the left and right sides of the main body. The main body has a configuration in which an upper substrate 33 and a lower substrate 34 are vertically arranged using support columns. The upper substrate 33 is provided with guide rails 35 and 36 installed at a predetermined interval on the front and rear, and the above-mentioned stamp holder support 13 is attached to the guide rails 35 and 36 so as to be movable in the right and left direction. Therefore, the stamp holder support 13 reciprocates between the print station 31 and the ink replenishment station 32, and executes microcontact printing while repeating ink replenishment and printing.

  The stamp holder support 13 is provided with the stamp holder 12 on its upper surface, and three load cells (Tiac products) are arranged at equiangular intervals on the concentric circle as the sensor means 14. Three positioning pins 37 are provided at equiangular intervals in the middle position of these three load cells to prevent rotational blurring. The stamp holder 12 has a circular planar shape similar to that shown in FIGS. 1A and 2A, and has a window 12a at the center.

  An example of a pressurizing mechanism provided at the position of three load cells as the sensor means 14 is shown in detail in FIG. In the pressurizing mechanism in the example of FIG. 5, a lever 39 having a fixed claw 16 is rotatably provided using a support shaft 38 planted at a predetermined position of the stamp holder support base 13. Each fixed claw 16 is disposed on the shaft by rotation around the support shaft 38 from a position off the axis of the sensor means 14, and the locking portion 41 hits the stopper 42 at that position and is positioned. Is configured to stop. The illustrated lever 39 is attached to a retaining nut 43 with an elastic member 44 made of a resin piece or a spring interposed therebetween, and applies a pressurizing pressure as an initial pressure.

  On the other hand, a work base 22 for fixing the work 21, a parallel adjustment mechanism 23 for parallelizing the work base 22, and an XYZΘ alignment mechanism 24 are arranged on the lower substrate 34. In the example shown in FIG. 4, the parallel adjustment mechanism 23 is shown as using a spherical bearing system, and the means 45 and 45 ′ for fixing the work 21 are shown as using a vacuum suction system. The XYZΘ alignment mechanism 24 has an X-axis at the bottom, a Y-axis above it, a Z-axis above it, and a Θ-axis alignment mechanism at the top. Since a set is necessary, the ink replenishment station side is distinguished by adding a dash. The Z-axis alignment mechanism uses a torque control motor with a speed limiting function (Sanmei Products Co., Ltd.). Reference numerals 46 and 47 denote holding portions for carrying the stamp holder, and 48 denotes a receiving portion, which makes point contact with the fixed claw 16. Although not shown in FIGS. 3 and 4, the apparatuses shown in these figures also have a finder microscope as in the case of FIG. 6.

  The operation of the print pressure detecting device 30 in the microcontact printing according to the present invention configured as described above will be described. In a state where the stamp holder 12 having the stamp 11 fixed to the lower surface is held, the stamp holder support 13 is parallelized at each of the print station 31 and the ink replenishment station 32. By bringing the stamp 11 into contact with the ink holder 48 having a chemical solution, the ink is replenished and the stamp holder support 13 is moved from the ink replenishment station 32 to the print station 31.

  For the stamp holder support 13 returned to the print station 31, the work 21 is raised by the Z-axis alignment mechanism, but this is detected because the pressure by the pressurizing mechanism is applied to the load cell. In the pressure management section, the load is reset to zero. This reset operation is equivalent to detecting a predetermined load, that is, an initial load on the side holding the stamp 11. When the workpiece 21 is raised by the Z-axis alignment mechanism, the workpiece 21 comes into contact with the stamp 11, and the contact pressure is detected by the sensor means 14, and when the specified pressure is reached, the Z-axis movement stops. The contact pressure value includes the load of the stamp (mold) 11 and the photomask 17.

  The present invention can be applied to an application that needs to control the contact pressure between two objects such as a workpiece and a stamp with high accuracy. For example, the present invention can be applied to an optical nanoimprint technique in which a mold having a minute unevenness is pressed against a plastically deformable substance (for example, a photocuring resin). In the present invention, since the contact pressure can be measured at a very high speed (real time), the measurement and control of the contact pressure of a substance whose reaction force changes depending on the contact time, such as an elastic body and a plastic deformation material as well as a rigid body. It is possible to use it.

BRIEF DESCRIPTION OF THE DRAWINGS Example 1 of the printing pressure detection method in the micro contact printing based on this invention is demonstrated, A is a top view and B is a front view. Furthermore, Example 1 of the printing pressure detection method according to the present invention will be described, in which A is a plan view and B is a front view. The top view which shows an example of the printing pressure detection apparatus in the micro contact printing which concerns on this invention. The front view which shows the apparatus of this invention corresponding to FIG. Sectional drawing which shows the pressurization mechanism in the apparatus of this invention. Schematic explanatory drawing for demonstrating the action | operation of the method and apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Stamp 12 Stamp holder 13 Stamp holder support stand 14 Sensor means 15 Chemical solution 16 Fixing claw 17 Photomask 18 Weight 21 Work 22 Work stand 23, 23 'Parallel adjustment mechanism 24, 24' XYZΘ alignment mechanism 25 Base 30 Micro contact printing device 31 Print Station 32 Ink Replenishment Station 33 Upper Substrate 34 Lower Substrate 35, 36 Guide Rail 38 Support Shaft 39 Lever 41 Locking Part 42 Stopper 43 Nut 44 Elastic Member 45 Means for Fixing the Work 46, 47 Holding for Transporting the Stamp Holder Part 48 Receiver

Claims (4)

The stamp and workpiece are paralleled, and the stamp is replenished with a chemical as a transfer agent. In order to transfer the chemical to the workpiece by bringing the stamp and the workpiece relatively close to each other and contacting them with the required contact pressure. A method for managing the contact pressure,
The means for pressurizing the initial pressure to the stamp holder holding the stamp is a pressurizing means including pressurization by a weight that can be moved in accordance with the rising amount of the workpiece. Applying a predetermined load, the value is detected as the initial pressure, the work placed below the stamp is raised with respect to the stamp, the contact pressure is applied, the contact pressure is detected, and the stamp is held. A method for detecting a print pressure in microcontact printing, wherein a difference between an initial pressure applied to a side to be touched and the contact pressure is detected as a print pressure. The stamp and the workpiece are paralleled, and the stamp is replenished with a chemical as a transfer agent. In order to transfer the chemical to the workpiece by bringing the stamp and the workpiece relatively close to each other and contacting them with the required contact pressure. An apparatus for implementing a method for managing contact pressure,
A stamp holder that holds the stamp on the bottom surface and a stamp holder support that supports the stamp holder at the periphery, and a plurality of sensor means that contact the stamp holder and detect contact pressure as a set. The stamp holder is placed between the holder and the stamp holder support base, and a plurality of sensor means are placed on it. Equipped with a pressurizing mechanism consisting of pressurizing means including pressurization with possible weights ,
An elevating mechanism that raises the workpiece relative to the stamp is arranged below the stamp, and contact pressure is applied to the stamp by the workpiece by the operation of the elevating mechanism.
The set of sensor means detects the initial pressure applied to the side holding the stamp, detects the contact pressure of the workpiece against the stamp, and uses the difference between the initial pressure and the contact pressure as the print pressure. A print pressure detecting device for micro contact printing, characterized by detecting. The pressurizing mechanism is a fixed claw provided rotatably on the stamp holder support base, and each fixed claw is provided for each sensor means, and is arranged on the axis from the position off the axis of the sensor means by rotation. The print pressure detecting device for micro contact printing according to claim 2, wherein the print pressure detecting device is configured so as to be configured as described above. 3. The print pressure detecting device for micro contact printing according to claim 2, wherein the stamp holder has a circular plane shape and has three load cells arranged at equiangular intervals on a concentric circle.

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