JP2006198485A - Spin coat apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spin coat apparatus capable of shortening a film-forming time while suppressing generation of ununiformness. <P>SOLUTION: The spin coat apparatus 10 is provided with a rotation driving part 14 for retaining a circular disc-like substrate 12 in the approximately horizontal state and rotating/driving it; and a nozzle part 20 having a lengthy slit-like delivery port 16, arranged such that the delivery port 16 extends from a center side of the substrate 12 to an outer periphery side and delivering a fluent material 18 from the delivery port 16 onto the substrate 12. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a spin coater used for forming a recording layer or the like of an optical recording medium.

  Optical recording media such as CD (Compact Disc) and DVD (Digital Versatile Disc) are widely used as information recording media. Furthermore, in recent years, optical recording media that can record high-capacity and large-capacity information by using blue or blue-violet laser light as irradiation light are becoming widespread.

  Such optical recording media are roughly classified into a ROM (Read Only Memory) type in which data cannot be additionally written or rewritten, a R (Recordable) type in which data can be additionally written only once, and a RW (Rewritable) type in which data can be rewritten. The

  As a material for the recording layer of the R-type optical recording medium, organic dyes whose optical characteristics change when irradiated with laser light are widely used. A spin coating method is used as a method for forming an organic dye film on a substrate of an optical recording medium.

  Further, in some optical recording media using blue or blue-violet laser light as irradiation light, a cover layer of about 0.1 mm thinner than the substrate is formed. In order to form such a thin cover layer In some cases, a spin coating method is used.

  The spin coater includes a rotation driving unit for holding and rotating a disk-shaped substrate in a substantially horizontal state, and a cylindrical nozzle unit (see, for example, Patent Document 1). When a predetermined amount of a fluid material such as a liquid organic dye dissolved in a solvent is ejected from the nozzle part to the vicinity of the center of the substrate and the substrate is driven to rotate, the fluid material flows to the outer peripheral side by centrifugal force and onto the substrate. Can be spread. By appropriately adjusting the viscosity of the flowable material, the discharge amount of the flowable material per unit time, the rotation speed of the substrate, and the like, a favorable film formation in which unevenness is suppressed can be realized.

  On the other hand, the optical recording medium is strongly required to improve the production efficiency, and the film formation process using such a spin coating method is also required to shorten the film formation time.

  On the other hand, the film formation time can be shortened by increasing the discharge amount per unit time of the fluid material discharged from the nozzle portion.

Japanese Patent Laid-Open No. 5-115825

  However, when the discharge amount per unit time of the fluid material is increased, there is a problem that unevenness such as a radial pattern is generated on the surface of the film. When the discharge amount of the fluid material per unit time becomes a certain level or more, it is difficult to suppress such unevenness even if conditions such as the rotation speed of the substrate are adjusted.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a spin coating apparatus capable of reducing the film formation time while suppressing the occurrence of unevenness.

  The present invention includes a nozzle portion having an elongated slit-like discharge port, and the flowable material is disposed on the substrate from the discharge port by arranging the nozzle portion so that the discharge port extends from the center side to the outer peripheral side of the substrate. The above-described object is achieved by a spin coater configured to discharge the liquid.

  Thus, since the fluid material is ejected from the ejection port with the slit-shaped ejection port extending from the center side to the outer peripheral side of the substrate, the conventional spin coating that ejects the fluid material only near the center of the substrate The fluid material can be applied to the entire surface of the application region of the substrate in a shorter time than the apparatus, and the film formation time can be shortened.

  That is, the above object can be achieved by the following invention.

(1) It has a rotation drive unit for holding and rotating a disk-shaped substrate in a substantially horizontal state, and an elongated slit-shaped discharge port, and the discharge port extends from the center side to the outer peripheral side of the substrate. A spin coater comprising: a nozzle portion arranged to extend and configured to discharge a flowable material from the discharge port onto the substrate.

(2) In (1), the nozzle part includes a storage part for storing the flowable material, and the storage part and the discharge port have a length equal to or greater than the length of the discharge port. A spin coating apparatus, characterized in that it communicates via a pipe line having a shape.

(3) In the spin coating apparatus according to (1) or (2), the discharge port of the nozzle portion has a shape in which the gap increases from the center side to the outer peripheral side of the substrate.

(4) In any one of (1) to (3), the nozzle portion is disposed such that a longitudinal direction of the discharge port is inclined with respect to a radial direction of the substrate, and the fluidity is provided on the substrate. A spin coater configured to discharge a material.

(5) In any one of (1) to (4), a plurality of the nozzle portions are provided, and a fluid material is discharged onto the substrate at a plurality of positions having different phases in the circumferential direction of the substrate. A spin coating apparatus characterized by the above.

  According to the present invention, the film formation time of the fluid material can be shortened while suppressing the occurrence of unevenness.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

  As shown in FIGS. 1 to 4, the spin coater 10 according to the first embodiment of the present invention has a rotation drive unit 14 for holding and rotating a disk-shaped substrate 12 in a substantially horizontal state. And an elongated slit-like discharge port 16, which is disposed so as to extend from the center side to the outer peripheral side of the substrate 12, and the flowable material 18 is placed on the substrate 12 from the discharge port 16. And a nozzle portion 20 configured to discharge.

  The substrate 12 is a substrate of an optical recording medium, and has a center hole 12A having a diameter of about 120 mm, a thickness of 0.6 to 1.2 mm, and an inner diameter of about 15 mm. In addition, the area | region where the fluid material 18 is apply | coated in the board | substrate 12 is an area | region where an internal diameter is a little larger than the internal diameter of 12 A of center holes, and the fluid material 18 is not apply | coated around 12 A of center holes. Further, the substrate 12 has a concave / convex pattern (not shown) such as a groove for information transmission formed on one side or both sides. A reflective layer or the like is formed in advance on the surface on which the uneven pattern is formed, if necessary. The substrate 12 is held by the rotation drive unit 14 so that the surface on which the uneven pattern is formed faces upward.

  The rotation drive unit 14 is fitted to the substrate 12 in the center hole 12A and holds the substrate 12 in a detachable manner. The rotation drive unit 14 is configured to rotate the substrate 12 by rotating a portion fitted to the substrate 12 around a vertical axis.

  The fluid material 18 is a raw material for a recording layer of an R type optical recording medium in which, for example, an organic dye or the like is dissolved in a solvent.

  The nozzle unit 20 is attached to a transfer mechanism (not shown) and is movable. The discharge port 16 is provided at the lower end of the nozzle portion 20. The discharge port 16 has a substantially rectangular cross section, and the (long side) length is substantially equal to the radial width of the region where the fluid material 18 is applied on the substrate 12. On the other hand, the gap (short side) of the discharge port 16 is several mm or less. For example, when the viscosity of the flowable material 18 is about 10 cp or lower, the gap on the short side of the discharge port 16 is preferably about 0.05 to 0.15 mm. In this case, the vertical gap between the lower end of the nozzle portion 20 and the upper surface of the substrate 12 is preferably about 0.05 to 0.2 mm.

  The nozzle unit 20 includes a storage unit 22 for storing the fluid material 18. The reservoir 22 and the discharge port 16 communicate with each other via a conduit 24 having a cross-sectional shape having a length equivalent to the length of the discharge port 16. The reservoir 22 is provided above the discharge port 16, and has a slightly larger cross-sectional shape in both the length direction and the gap direction than the cross-sectional shape of the discharge port 16. The reservoir 22 is connected to a pipe (not shown) for supplying the fluid material 18. The pipe line 24 communicates with the storage part 22 in a shape in which the cross-sectional shape of the discharge port 16 extends upward.

  Specific examples of the structure of the nozzle unit 20 include, for example, a front member and a rear member that are divided on both sides in the gap direction of the discharge port 16, and a substantially U-shaped shim member that is sandwiched between them and opens downwardly. Can be listed. In this case, the thickness of the shim member corresponds to the gap of the discharge port 16, and the width of the opening of the shim member corresponds to the length of the discharge port 16.

  Next, a method for forming the fluid material 18 using the spin coater 10 will be described.

  First, the substrate 12 is held by the rotation drive unit 14 so that the surface of the substrate 12 on which the concave / convex pattern is formed faces upward.

  Next, the end portion of the discharge port 16 in the length direction is positioned near the upper end of the radial direction of the application target region of the flowable material 18 on the substrate 12, and the discharge port 16 approaches the upper surface of the substrate 12. Thus, the nozzle part 20 is moved. At this time, the nozzle portion 20 is arranged so that the longitudinal direction of the discharge port 16 is along the radial direction of the substrate 12. Further, the vertical position of the nozzle unit 20 is determined so that the vertical gap between the lower end of the nozzle unit 20 and the upper surface of the substrate 12 is approximately the same as the gap of the discharge port 16.

  Next, the fluid material 18 is discharged onto the substrate 12 from the discharge port 16 of the nozzle unit 20 while the substrate 12 is rotationally driven by the rotational drive unit 14 at a low rotational speed of about 0 to 500 rpm. still. After the discharge of the flowable material 18 is started, the discharge of the flowable material 18 is continued until the substrate 12 rotates at least once or more. Thereby, the fluid material 18 is discharged over the entire surface of the substrate 12 where the fluid material 18 is to be applied.

  Further, by increasing the rotation speed of the substrate 12 to about 3000 rpm, the discharged fluid material 18 flows radially outward by centrifugal force to reduce the film thickness, and is leveled to a predetermined uniform film thickness. And the solvent evaporates and dries.

  Thus, since the fluid material 18 is ejected from the ejection port 16 in a state where the slit-like ejection port 16 extends from the center side to the outer peripheral side of the substrate 12, the fluid material is ejected only near the center of the substrate. The fluid material 18 can be applied to the entire surface of the application region of the substrate 12 in a shorter time than the conventional spin coating method, and the film formation time can be shortened.

  The nozzle unit 20 includes a storage unit 22 for storing the fluid material 18, and the storage unit 22 and the discharge port 16 have a pipe line 24 having a cross-sectional shape having a length equivalent to the length of the discharge port 16. Therefore, the flowable material 18 can be uniformly discharged from the slit-like elongated discharge port 16, and the occurrence of unevenness is suppressed.

  Further, the position of the nozzle portion 20 in the vertical direction is determined so that the vertical gap between the lower end of the nozzle portion 20 and the upper surface of the substrate 12 is the same as the gap of the discharge port 16, and the flowable material 18 is disposed. Since the liquid material is discharged, dripping and splashing of the fluid material 18 are suppressed, and the occurrence of unevenness is also suppressed in this respect.

  In the first embodiment, the nozzle portion 20 includes a storage portion 22 for storing the fluid material 18, and the storage portion 22 and the discharge port 16 have a length equivalent to the length of the discharge port 16. Although it communicates via the pipe line 24 having a cross-sectional shape, the storage portion may be omitted as long as the fluid material 18 can be uniformly discharged from the slit-like elongated discharge port 16.

  In the first embodiment, the length of the discharge port 16 is substantially equal to the width in the radial direction of the region where the fluid material 18 is applied on the substrate 12. Even when the width of the region to which the fluid material 18 is applied is shorter than the radial width, the entire surface of the application region of the substrate 12 can be obtained in a shorter time than the conventional spin coating method in which the fluid material is discharged only near the center of the substrate. Since the fluid material 18 can be applied to the film, the effect of shortening the film formation time can be obtained.

  In the first embodiment, as the fluid material 18, an example in which an organic dye or the like is dissolved in a solvent and a raw material for a recording layer of an R type optical recording medium is applied to the substrate 12 is shown. The film formation time can be shortened by applying the present invention to the other layers of the recording medium and the film forming process in fields other than the optical recording medium.

  In the first embodiment, the discharge port 16 has a substantially rectangular shape with a uniform gap. However, if the discharge port 16 has a slit shape, for example, the discharge port 16 has a curved shape such as a long arc or a gap is a part Different discharge ports may be used.

  For example, as in the second embodiment of the present invention shown in FIG. 5, the discharge port 16 of the nozzle portion 20 may have a shape in which the gap increases from the center side to the outer peripheral side of the substrate 12. By doing in this way, the discharge amount per unit time of the fluid material 18 in the site | part of the outer peripheral side of the board | substrate 12 becomes larger than the discharge quantity per unit time in the site | part of the center side. Since the area of the region is wider on the outer peripheral side than on the center side, the effect of making the film thickness of the fluid material 18 uniform can be enhanced.

  In the first embodiment, the nozzle portion 20 is disposed so that the longitudinal direction of the discharge port 16 is along the radial direction of the substrate 12, and the fluid material 18 is discharged onto the substrate 12. As in the third embodiment of the present invention shown in FIG. 6, the nozzle portion 20 is arranged so that the longitudinal direction of the discharge port 16 is inclined with respect to the radial direction of the substrate 12, and the fluidity is provided on the substrate 12. The material 18 may be discharged.

  Since the fluid material 18 discharged onto the substrate 12 flows radially outward by centrifugal force, the nozzle portion 20 is arranged so that the longitudinal direction of the discharge port 16 is along the radial direction of the substrate 12. When the fluid material 18 is discharged onto the substrate 12, among the fluid material 18 discharged onto the substrate 12, the boundary portion first ejected on the substrate 12 flows through the centrifugal force even if the boundary portion flows. There is a tendency to maintain the shape along the direction, and when the substrate 12 makes one round after the start of discharge, the flowable material 18 is further discharged along the radial direction to the boundary portion along the radial direction, and a step is easily formed. On the other hand, if the flowable material 18 is discharged so as to be inclined with respect to the radial direction, the discharged flowable material 18 flows outward in the radial direction as the substrate 12 rotates, and the shape of the boundary portion changes. Therefore, after the start of discharge, when the substrate 12 makes one round, even if the fluid material 18 is further discharged, the above-described remarkable step is hardly generated, and the film thickness of the fluid material 18 is made uniform. Can be increased.

  Further, in the first and third embodiments, the spin coater 10 includes only one nozzle portion 20, but the nozzle portion 20 is provided as in the third embodiment of the present invention shown in FIG. A plurality of fluid materials 18 may be ejected onto the substrate 12 at a plurality of positions where the circumferential phase of the substrate 12 is different.

  In this way, the film formation time can be further shortened. FIG. 7 shows an example in which the two nozzle portions 20 are arranged with a phase different by 180 °. However, for example, the three nozzle portions 20 may be arranged with a phase different by 120 °. The nozzle unit 20 may be arranged with a phase different by 90 °.

  The present invention can be used for forming a recording layer of an optical recording medium.

The top view which shows typically schematic structure of the principal part of the spin coater concerning 1st Embodiment of this invention Side view Bottom view schematically showing the structure around the discharge port of the nozzle part of the spin coater The perspective view which shows the schematic structure of the nozzle part typically The bottom view which shows typically the structure around the discharge outlet of the nozzle part which concerns on 2nd Embodiment of this invention. The top view which shows typically schematic structure of the principal part of the spin coater concerning 3rd Embodiment of this invention The top view which shows typically schematic structure of the principal part of the spin coater concerning 4th Embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Spin coat apparatus 12 ... Substrate 14 ... Rotation drive part 16 ... Discharge port 18 ... Flowable material 20 ... Nozzle part 22 ... Storage part 24 ... Pipe line

Claims (5)

  A rotation drive unit for holding and rotating the disk-shaped substrate in a substantially horizontal state, and an elongated slit-shaped discharge port, the discharge port extending from the center side of the substrate to the outer peripheral side And a nozzle part configured to discharge a fluid material from the discharge port onto the substrate. In claim 1,
The nozzle part includes a storage part for storing the flowable material, and the storage part and the discharge port have a cross-sectional shape having a length equal to or greater than the length of the discharge port. A spin coat apparatus characterized by being in communication. In claim 1 or 2,
The spin coater according to claim 1, wherein the discharge port of the nozzle part has a shape in which a gap increases from a center side to an outer peripheral side of the substrate. In any one of Claims 1 thru | or 3,
The nozzle portion is arranged so that a longitudinal direction of the ejection port is inclined with respect to a radial direction of the substrate, and is configured to eject the fluid material onto the substrate. Coat equipment. In any one of Claims 1 thru | or 4,
A spin coater comprising a plurality of the nozzle portions and configured to discharge a flowable material onto the substrate at a plurality of positions having different circumferential phases of the substrate.

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