KR20110067237A - Coating apparatus for cylindrical substrate using magnetic levitation - Google Patents

Abstract

PURPOSE: A coating apparatus for a cylindrical substrate using magnetic levitation is provided to perform thin coating with high accuracy over the area of the cylindrical structure by rotating a substrate fixing unit in contactless through magnetic levitation. CONSTITUTION: A base unit(20) comprises a coil assembly. The base unit supports a substrate fixing unit from a lower part without contacting it and is rotatable. A magnetic levitating type substrate fixing unit comprises a magnetism assembly(12) which is arranged on the coil assembly. A cylindrical substrate(1) is mounted in the magnetic levitating type substrate fixture A nozzle unit(30) ejects a coating solution through a nozzle on the surface of the cylindrical substrate which is magnetically levitated and rotated.

Description

Coating apparatus for cylindrical substrate using magnetic levitation

The present invention relates to a coating apparatus, and more particularly, to a coating apparatus for coating by coating a liquid coating liquid on the surface of a cylindrical substrate.

Generally, the most basic process of the semiconductor process is lithography, which involves uniformly applying a photoresist of several nm to several μm on a wafer.

As a method of applying a photosensitive agent to a wafer, spray coating, roll coating, spin coating, etc. are generally used.

Spray coating and roll coating are widely used for coating large-area substrates, but spin coating is generally used to form high-precision patterns because they are not suitable for high precision in coating uniformity and film thickness adjustment.

The principle of the spin coating is to hold a wafer made in a disk shape with a vacuum chuck and rotate at a constant speed to apply a constant centrifugal force to the photosensitive agent on the wafer, thereby forming a coating film having a uniform thickness.

As spin coaters are widely used in the semiconductor industry, much research has been conducted on the improvement of devices.

As an example, a spin coater (patent no. 585019) having a function of automatically adjusting a thickness variation of a photosensitive agent by adding a thickness measuring sensor to the spin coater, by coating a photosensitive agent on a wafer and irradiating the exposure light to the edge Method and apparatus for removing edge bead of non-uniform thickness (Patent No. 663013), coated in vacuum to eliminate the flow of air generated when the photoresist is pushed to the wafer edge by centrifugal force The apparatus (patent patent 585019) etc. which adjust the thickness of a photosensitizer uniformly are mentioned.

However, these devices are basically an invention of an existing spin coater for coating a flat plate material, and there is no development of a spin coater for coating a three-dimensional cylindrical material.

As patents of a similar technology, there are patents relating to a coated substrate having a curved surface and a method of manufacturing the coated substrate, a spotlight having the coated substrate, and a method and apparatus for coating the substrate (registered patent No. 721559). It includes the content of photoresist coating and photographic processes for a portion of the surface.

Its contents describe a method of spraying a photosensitive agent while maintaining a constant distance between a curved surface and a nozzle through a computer controlled inkjet nozzle.

This is not suitable for high precision in coating film uniformity and film thickness adjustment, such as spray coaters, and is inappropriate for coating the entire area of a curved cylindrical substrate.

Therefore, the present invention has been invented to solve the above problems, and an object thereof is to provide a coating apparatus for a cylindrical substrate that can apply a coating liquid uniformly to a cylindrical substrate and enable high-precision coating.

In order to achieve the above object, the present invention,

A base portion having a coil assembly;

Having a permanent magnet assembly disposed above the coil assembly, magnetic levitation, rotation, and axial movement are provided by the interaction between the permanent magnet assembly and the coil assembly to which power is applied. A magnetic levitation substrate fixing unit on which a cylindrical substrate is mounted;

A nozzle unit for spraying and applying a coating liquid supplied from a coating liquid supplying unit to a surface of a cylindrical substrate which is rotated in a magnetically injured state together with the substrate fixing unit;

It provides a coating apparatus for a cylindrical substrate comprising a.

In a preferred embodiment, the substrate fixing portion is characterized in that it comprises a shaft portion fitted with a cylindrical substrate on the outer periphery, and a permanent magnet assembly mounted to both ends of the shaft portion.

In addition, the nozzle unit is characterized by having a plurality of nozzles disposed around the cylindrical substrate to improve the uniformity of coating liquid coating.

In addition, the nozzles are characterized in that the nozzles are arranged at regular intervals along the circumferential direction on the cross section of the cylindrical substrate.

In addition, the nozzles are characterized in that the nozzles are arranged to be symmetrically positioned in the up / down / left / right position on the cross section of the cylindrical substrate.

In addition, the nozzle unit is a ring type configuration that connects one nozzle to the main supply pipe and the coating liquid supplied from the main supply pipe is distributed to each nozzle by connecting adjacent nozzles with each other so that the coating liquid is transferred between the nozzle and the nozzle. It features.

In addition, the nozzle unit is characterized in that it comprises a position adjusting means for adjusting the position of the nozzle so that the distance between the cylindrical substrate and the nozzle can be adjusted.

In addition, the position adjusting means is characterized by comprising a cylinder device as an actuator for adjusting the position of the nozzle and mounting the nozzle to the tip of the piston rod which is controlled forward and backward operation of the cylinder device.

In addition, the position adjusting means includes a screw shaft rotated by the motor and its driving, a guide portion for guiding the nozzle body integral with the nozzle, and screwing the screw shaft to the nozzle body to rotate the screw shaft when the motor is driven, the nozzle body Is characterized in that the linear drive device of the screw drive system configured to be forward and backward.

Accordingly, according to the coating apparatus for a cylindrical substrate of the present invention, the substrate fixing portion for fixing the cylindrical substrate is configured to rotate in a non-contact manner by the magnetic levitation method, so that the position, attitude, and rotational speed of the substrate fixing portion is precisely controlled and the cylindrical substrate It is possible to perform a thin, uniform and high precision coating process over the entire area of the substrate.

In particular, since the position of the cylindrical substrate can be actively controlled with an error of nanometer size, it is possible to correct errors and disturbances due to machining in real time, and improve the coating uniformity of the coating liquid.

In addition, in the coating apparatus of the present invention, each nozzle of the nozzle unit is fixed to the position during the coating liquid coating operation, instead of the cylindrical substrate is fixed to the fixed substrate is configured to perform the coating operation, the vibration that may occur when the nozzle portion moves during coating liquid coating Process error due to this can be reduced.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

The present invention relates to a coating apparatus for coating by coating a liquid coating liquid on the surface of a cylindrical substrate, and more particularly, to a coating apparatus using a magnetic levitation method. That is, the coating liquid is uniformly applied to the surface of the cylindrical substrate by spraying the coating liquid on the surface of the rotating cylindrical substrate in the state of rotating the magnetic substrate by magnetic levitation.

Such a coating device of the present invention can be used as a coating device for applying a photosensitive agent to a cylindrical substrate in a photographic process. In this case, the cylindrical substrate to be coated is a cylindrical substrate on which a photosensitive agent is coated in a photographic process, and the coating liquid is a photosensitive agent.

The cylindrical substrate is not limited as long as it can be applied to the photosensitive agent, for example, a cylindrical substrate made of a metal, such as aluminum, stainless steel, ceramic, glass, plastic material may be used. However, considering the baking process, it should be a material that is thermally stable up to the temperature at which the photosensitive agent is baked.

Hereinafter, referring to the configuration of the coating apparatus according to an embodiment of the present invention, Figure 1 is a front view showing the configuration of the coating apparatus according to the present invention, Figure 2 is a substrate fixed to the upper side of the base in the coating apparatus according to the present invention It is a figure which shows the state of an additional magnetic injury.

3 is a perspective view illustrating an example of a coil assembly and a permanent magnet assembly for magnetic injuries, and FIG. 4 is a configuration diagram illustrating an example of a nozzle unit.

As shown, the coating apparatus according to an embodiment of the present invention, the base unit having a coil assembly (reference numeral 21 in FIGS. 2 and 3); Magnetic permanent injury, rotation, and shaft by the interaction between the permanent magnet assembly 12 and the coil assembly 21 to which power is applied while having a permanent magnet assembly 12 disposed above the coil assembly 21. It is provided to be capable of moving in the direction, the magnetic substrate upper substrate fixing portion 10 is mounted on which the cylindrical substrate (1) to be coated; A coating liquid (eg, a photosensitive agent) supplied from a coating liquid supplying part (not shown) is sprayed on the surface of the cylindrical substrate 1 which is rotated in a magnetically injured state together with the substrate fixing part 10 by spraying through a nozzle 32. It includes a nozzle unit 30 to be.

First, the base portion 20 has a coil assembly 21 for generating a magnetic levitation force, a magnetic rotation force, a magnetic transfer force by interaction with the permanent magnet assembly 12, the substrate fixing portion 10 from the lower side It becomes a structure part which rotatably supports noncontact.

The current applied to the coil assembly 21 in the base portion 20 is controlled by a controller (not shown), so that the axial direction (left and right directions on the drawing) of the substrate fixing part 10, the axial movement speed and rotation Speed and so on.

The coil assembly 21 of the base portion 20 must support the substrate fixing portion 10 by interacting with the permanent magnet assembly 12 disposed at both ends of the substrate fixing portion 10 so that the coil assembly 21 of the base portion 20 is permanent on both sides of the drawing. It is disposed to be located below the magnet assembly 12.

The magnetic levitation substrate fixing part 10 is a portion that fixes the cylindrical substrate 1 and becomes a component that rotates in a non-contact manner in the base portion 20 by magnetic levitation. While the movement is controlled, the cylindrical substrate 1 is configured to linearly move in the axial direction.

In a preferred embodiment, the substrate fixing portion 10 includes a shaft portion 11, the cylindrical substrate 1 is fitted and fixed on the outer periphery, and a permanent magnet assembly 12 mounted to both ends of the shaft portion 11 It is composed.

The shaft portion 11 is a circular cross section of the shaft, that is, a solid tube structure or a hollow tube, that is made of a hollow tube structure can be used to reduce the weight, all can be used, and the cylindrical substrate (1) is fitted and fixed on the outer periphery It is manufactured to have an outer diameter in consideration of the inner diameter of the substrate.

The permanent magnet assembly 12 is assembled to both ends of the shaft portion 11 so as to be located above the coil assembly 21 of the base portion 20, the plurality of permanent magnets on the outer periphery of the shaft portion 11 It can be configured by arranging them in an annular shape.

During the process, the shaft portion 11, the cylindrical substrate 1, and the permanent magnet assembly 12 must all rotate integrally above the base portion 20, so that the cylindrical substrate 1 and the permanent magnet assembly 12 are disposed on the shaft portion 11. Fixing means for fixing the integrally rotatable is required, which is not particularly limited since the present invention can be applied in various ways.

For example, although not shown in the drawings, the cylindrical substrate 1 is fixed to the shaft portion 11 by using a fastening means such as a screw, a long bolt, a clamp, or a fitting structure, and the shaft portion 11 is fixed to the cylindrical substrate ( The method of pressing and fixing on the inner circumference of 1) may be applied.

In the case of the permanent magnet assembly 12, the frame fixing the permanent magnet to the shaft portion 11 is fixed using a known fastening means such as a screw, a long bolt, a clamp, a fitting structure, or a permanent magnet shaft portion ( 11) may be applied using a fastening means that can be fixed directly to.

Alternatively, the shaft portion 11 may be manufactured in a circular tube, and then the permanent magnet assembly 12 may be press-fitted into the inner circumferential surface of the shaft portion 11 to fix the shaft portion 11. Only the cylindrical substrate 1 may be disposed on the outer circumference of the shaft portion 11. Mount it.

However, since the cylindrical substrate 1 is inserted into the center of the shaft portion 11 in the substrate fixing portion 10 and the permanent magnet assembly 12 is disposed at both ends of the shaft portion 11, the cylindrical substrate 1 is disposed before the process. At least one or more of the two permanent magnet assemblies 12 on both sides may be easily detachable from the shaft 11 so as to be mounted on the shaft 11 and easily removed after the process.

Then, inserting a spacer between the permanent magnet assembly 12 and the cylindrical substrate 1 on both sides, or a blocking structure for preventing the liquid coating liquid applied to the cylindrical substrate 1 from moving to the permanent magnet assembly 12 Can be fixedly installed on the outer periphery of the shaft portion 11 between the permanent magnet assembly 12 and the cylindrical substrate 1.

Of course, the blocking structure may be installed as a structure protruding radially from the shaft portion 11, but should be installed so as not to interfere with the base portion 20 during magnetic levitation, rotation, and axial movement of the substrate fixing portion 10. .

As a result, the substrate fixing portion 10 having the above-described configuration is axially injured by the permanent magnet assembly 12 and the coil assembly 21 of the base portion 20 in a fixed state. Can move and rotate.

That is, the substrate fixing part 10 in the process by the magnetic levitation force, the magnetic rotation force, the magnetic transfer force generated between the permanent magnet assembly 12 and the coil assembly 21 of the base portion 20 is a cylindrical substrate (1) and In addition to rotating in a magnetic injury state as well as position control in the axial direction, at this time, the coating liquid supplied through the nozzle unit 30 is evenly applied to the surface of the cylindrical substrate 1 is made.

In the present invention, the magnetic levitation control can be performed by the control unit to control the current applied to the coil of the coil assembly 21, which is a method that is applied in the conventional magnetic levitation device having a basic configuration of the coil and the permanent magnet.

Basically, the substrate fixing part 10 should control the height of the magnetic levitation, and the axial movement and rotational movement in the left and right directions on the drawing bar. The controller receives the sensing value from a plurality of sensors installed around the substrate fixing part, In order to precisely control the position and posture of the substrate fixing part 10.

For example, the gap sensors 2a and 2b are installed above the permanent magnet assembly 12 of the substrate fixing portion 10 to control the height of the magnetic levitation of the substrate fixing portion 10 holding the cylindrical substrate 1. In order to control the axial position and movement of the substrate fixing portion 10, the gap sensor (3a, 3b) is provided on both ends of the substrate fixing portion 10, that is, the side of the permanent magnet assembly 12, In order to detect the rotation state (rotation speed, etc.) of the substrate fixing part 10, it is possible to install the rotation sensor 4 at one end side of the substrate fixing part 10.

Accordingly, the controller can precisely control the height of the magnetic levitation, the axial movement, and the rotational movement of the substrate fixing unit 10 based on the sensing values input from the respective sensors.

Prior to the start of the process, the permanent magnet assembly 12 of the substrate fixing part 10 remains on the base portion 20, and when driving power is applied to the coil assembly 21 of the base portion 20, it occurs at this time. The permanent magnet assembly 12 is magnetically injured by the force of the magnetic field, and the entire substrate fixing part 10 including the cylindrical substrate 1 is magnetically injured integrally. 10) is made to the left and right axial movement and rotation movement integrally with the cylindrical substrate (1).

The main factors that determine the coating thickness of the cylindrical substrate are the coating liquid (photosensitive) coating speed, the viscosity of the coating liquid, the moving speed and rotation speed of the cylindrical substrate, the distance between the cylindrical substrate 1 and the nozzle 32, and the like. A coating having a desired thickness can be applied to the surface of the rotating cylindrical substrate, and the coating liquid can be applied thinly and uniformly over the entire area of the cylindrical substrate.

Among the factors for determining the coating thickness, the coating speed and viscosity of the coating liquid are external factors, and the moving speed and rotation speed of the cylindrical substrate 1 are the magnetic levitation force, the magnetic rotational force, and the magnetic feed force of the substrate fixing part 10. It can be adjusted through the control of, and also as described later, the distance between the nozzle of the nozzle unit 30 and the cylindrical substrate 1 can also be adjusted, the coating apparatus of the present invention enables a high precision coating process.

In addition, in addition to fine control of coating thickness, actively controlling the axial position and rotational state of the substrate fixing part 10 and the cylindrical substrate 1 after magnetic levitation, the process error (thickness deviation, etc.) of the coating process is corrected in real time. It becomes possible.

On the other hand, the structure of a nozzle part is demonstrated as follows.

In the coating apparatus of the present invention, the nozzle unit 30 may be configured by a multi-injection method having a plurality of nozzles 32. When the plurality of nozzles 32 are provided, the nozzle unit 30 may increase the uniformity of coating liquid coating. have.

That is, after the plurality of nozzles 32 are disposed around the cylindrical substrate 1 mounted on the substrate fixing part 10 so as to increase the uniformity of coating liquid coating, the coating liquid is sprayed from each nozzle 32 at the same time. It is.

At this time, it is possible to arrange a plurality of nozzles 32 at regular intervals along the circumferential direction on the cross-section of the cylindrical substrate 1, preferably as shown in the up / down / left on the cross-section of the cylindrical substrate 1 It is possible to arrange to be symmetrically positioned at the right position.

As an embodiment having a plurality of nozzles, it is possible for the entire nozzle 32 to receive the coating liquid from one main supply pipe 31 connected to the coating liquid supply part. In this case, one nozzle is connected to the main supply pipe 31. It is possible to configure such that the coating liquid is transferred between the nozzle 32 and the nozzle by connecting the neighboring nozzles with each other with a connecting pipe 35.

Accordingly, the connecting pipe 35 may be connected between the nozzle 32 and the nozzle positioned around the cylindrical substrate 1 to form a ring-shaped nozzle unit 30 having a ring shape as a whole.

Of course, instead of the ring-type nozzle unit 30 as described above, it is also possible for each nozzle 32 to be dispensed with the coating liquid from the main supply pipe 31 through each branch pipe.

And, in the nozzle unit 30 according to the present invention, the nozzles 32 may be installed to enable distance adjustment with the cylindrical substrate 1 to adjust the coating thickness, as shown in the embodiment of the ring type nozzle In the unit 30, each nozzle 32 is provided to enable the front and rear position adjustment in the radial direction about the cylindrical substrate (1).

To this end, the connector 35 should be a flexible structure, it is possible to use a bellows tube or a flexible hose as the connector. When using flexible hoses, the nozzles are connected to each other with a hose that is longer than the gap between the nozzles and the nozzles.

In the nozzle unit 30 configured as described above, the distance adjustment with the cylindrical substrate 1, that is, the front-rear position adjustment of each nozzle 32, after adjusting the distance with the cylindrical substrate 1 is carried out to determine each nozzle of the coating apparatus. It can be carried out in a manner that is manually fixed to the position of the fixture.

At this time, the positions of the nozzles are fixed so that the distances between the nozzles 32 and the cylindrical substrate 1 are all equal to each other in accordance with a desired coating thickness at a predetermined height of the magnetic levitation of the substrate fixing part 10.

In addition, the position adjusting means for adjusting the position of the nozzle by the actuator for adjusting the position of each nozzle 32 may be provided, in one embodiment, the cylinder device 33 for adjusting the position of each nozzle 32 back and forth Position adjusting means including a) may be provided.

The cylinder device (33) has a piston rod (34) whose forward and backward motion is controlled by a control unit, and is installed one by one for each nozzle (32), integrally at the front end by the forward and backward motion of the piston rod (34) The front and rear positions of the mounted nozzle 32 can be adjusted.

The position adjusting means for adjusting the position of the nozzle can be variously changed and implemented as long as it is a configuration capable of adjusting the position of the nozzle back and forth, in addition to the configuration having the above-described cylinder device, and is not limited to the specific configuration in the present invention.

For example, a configuration that can be applied in addition to the positioning means having a cylinder device, which can linearly move each nozzle 32 and control the movement position of the nozzle, for example, is not illustrated in the drawings, A linear driving device having a motor fixed to the government and a screw shaft rotated by the motor drive can be applied.

That is, the body part of each nozzle is coupled to the guide part (for example, guide rail) provided long along the front-back movement direction (radial direction centering on the cylindrical board | substrate 1) of a nozzle to the fixing part of a coating apparatus, and rotated by a motor. By screwing the screw shaft to the body portion, the screw shaft is rotated as each motor is rotated so that the body portion of each nozzle is configured to linearly move along the guide portion.

At this time, if the control unit controls the driving of each motor, the rotation amount of the screw shaft can be controlled while the front and rear positions of the nozzle can be controlled.

As a result, in the nozzle unit 30 configured as described above, the positions of the nozzles 32 are basically fixed during the coating liquid coating operation, and the coating operation is performed while the substrate fixing part 10 having the cylindrical substrate 1 fixed thereon moves. Since the coating liquid is applied, process errors due to vibrations that may occur when the nozzle unit 30 moves may be prevented.

Thus, according to the coating apparatus according to the present invention, the substrate fixing portion 10 for fixing the cylindrical substrate 1 is configured to rotate in a non-contact manner by the magnetic levitation method, thereby the position and attitude of the substrate fixing portion 10 As the rotational speed is precisely controlled, a thin and uniform high precision coating process can be performed over the entire area of the cylindrical substrate 1.

In particular, since the position of the cylindrical substrate 1 can be actively controlled by an error of nanometer size, it is possible to correct errors and disturbances caused by machining in real time, and improve the coating uniformity of the coating liquid.

The embodiments of the present invention have been described in detail above, but the scope of the present invention is not limited to the above-described embodiments, and various modifications of those skilled in the art using the basic concepts of the present invention defined in the following claims and Improved forms are also included in the scope of the present invention.

1 is a front view showing the configuration of a coating apparatus according to the present invention.

Figure 2 is a view showing a state in which the substrate fixing the magnetic levitation above the base portion in the coating apparatus according to the present invention.

3 is a perspective view showing an example of a coil assembly and a permanent magnet assembly for magnetic levitation in the coating apparatus according to the present invention.

4 is a configuration diagram showing an example of a nozzle unit in the coating apparatus according to the present invention.

<Description of the symbols for the main parts of the drawings>

10: substrate fixing part 20: base part

30: nozzle part

Claims (9)

A base portion 20 having a coil assembly 21; Magnetic permanent injury, rotation, and shaft by the interaction between the permanent magnet assembly 12 and the coil assembly 21 to which power is applied while having a permanent magnet assembly 12 disposed above the coil assembly 21. A magnetic levitation substrate fixing part (10) provided to be capable of moving in a direction and mounted with a cylindrical substrate (1) to be coated; A nozzle unit 30 spraying the coating liquid supplied from the coating liquid supply unit through the nozzle 32 to the surface of the cylindrical substrate 1 which is rotated in a magnetically injured state together with the substrate fixing unit 10; Coating device for cylindrical substrate comprising a. The method according to claim 1, The substrate fixing portion 10 is characterized in that it comprises a shaft portion 11, the cylindrical substrate 1 is fitted on the outer periphery, and a permanent magnet assembly 12 mounted to both ends of the shaft portion 11 Coating device for cylindrical substrate. The method according to claim 1, The nozzle unit 30 is a coating apparatus for a cylindrical substrate, characterized in that provided with a plurality of nozzles (32) disposed around the cylindrical substrate (1) to improve the uniformity of coating liquid coating. The method of claim 3, Coating device for a cylindrical substrate, characterized in that the nozzles 32 of the nozzle unit 30 are arranged at regular intervals along the circumferential direction on the cross section of the cylindrical substrate (1). The method according to claim 4, Coating device for a cylindrical substrate, characterized in that the nozzles (32) of the nozzle unit 30 is arranged to be symmetrically positioned in the up / down / left / right position on the cross section of the cylindrical substrate (1). The method according to claim 4 or 5, The nozzle unit 30 connects one nozzle 32 to the main supply pipe 31 and connects the adjacent nozzles 32 to each other by a connection pipe 35 so that the coating liquid is transferred between the nozzle 32 and the nozzle. Coating device for a cylindrical substrate, characterized in that the ring-type configuration to distribute the coating liquid supplied from the main supply pipe 31 to each nozzle (32). The method according to claim 1 or 3, The nozzle unit 30 is a coating apparatus for a cylindrical substrate, characterized in that provided with a position adjusting means for adjusting the position of the nozzle 32 so that the distance between the cylindrical substrate (1) and the nozzle (32) can be adjusted. The method of claim 7, The position adjusting means includes a cylinder device 33 as an actuator for adjusting the position of the nozzle 32 and mounts the nozzle 32 on the piston rod 34 which controls the forward and backward operation of the cylinder device 33. Coating device for a cylindrical substrate, characterized in that configured. The method of claim 7, The positioning means includes a screw shaft that is rotated by a motor and its driving, and a guide part for guiding the nozzle body integral with the nozzle. Coating device for a cylindrical substrate, characterized in that the linear drive device of the screw drive system configured to be moved forward and backward.

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