JP2006243543A - Method for forming permanent pattern - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming a permanent pattern by which a cured film having excellent coating characteristics and producing no toxic gas on incineration can be formed and a permanent pattern can be efficiently formed with high definition by suppressing distortion in an image imaged on a photosensitive layer. <P>SOLUTION: The method for forming a permanent pattern is characterized in that a photosensitive layer is formed on the surface of a base material by using a photosensitive composition which contains at least a binder, a polymerizable compound, a photopolymerization initiator, a heat-crosslinking agent, and a colorant, but no halogen atom in the colorant, and then the photosensitive layer is exposed to a modulated light from a light irradiating means through a microlens array and developed; wherein the light from the light irradiating means is modulated by a light modulating means having n of imaging portions each of which receives the light from the light irradiating means and outputs the light, and the microlens array has an arrangement of either microlenses each having an aspheric surface which can correct aberration due to distortion in the exit surfaces of the imaging portions or microlenses each having a lens aperture pattern which prevents the light from a peripheral part of the imaging portion from entering. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention forms an image of light modulated by a light modulation means such as a spatial light modulation element on a photosensitive layer, exposes the photosensitive layer, and is used in a printed wiring board field including a package substrate or a semiconductor field. The present invention relates to a permanent pattern forming method for efficiently forming fine permanent patterns (protective films such as interlayer insulating films and solder resist patterns).

  An exposure apparatus is known in which light modulated by a spatial light modulator or the like is passed through an imaging optical system, an image formed by this light is formed on a predetermined photosensitive layer, and the photosensitive layer is exposed. The exposure apparatus basically includes a spatial light modulation element in which a large number of pixel portions that modulate irradiated light according to control signals are two-dimensionally arranged, and light to the spatial light modulation element. An illumination light source and an imaging optical system that forms an image of light modulated by the spatial light modulation element on the photosensitive layer are provided (see Non-Patent Document 1 and Patent Document 1).

  Examples of the spatial light modulation element include a liquid crystal display element (LCD), a digital micromirror device (DMD), etc. The DMD has an angle of a reflection surface as the pixel portion according to a control signal. This is a mirror device in which a large number of micromirrors to be changed are two-dimensionally arranged on a semiconductor substrate such as silicon.

  In the use of the exposure apparatus, there is often a demand for enlarging an image projected on the photosensitive layer, and in this case, an enlarged imaging optical system is used as the imaging optical system. However, in this case, if the light passing through the spatial light modulation element is simply passed through the magnification imaging optical system, the light flux from each picture element portion in the spatial light modulation element is enlarged and projected in the pattern. There is a problem in that the pixel size increases and the sharpness of the pixel decreases.

  Therefore, as described in Patent Document 1, a first imaging optical system is arranged in the optical path of the light modulated by the spatial light modulation element, and imaging by the first imaging optical system is performed. A microlens array in which microlenses corresponding to the respective pixel portions of the spatial light modulation element are arranged in an array is arranged on the surface, and the modulated light is in the optical path of the light that has passed through the microlens array. It has been proposed to arrange a second imaging optical system that forms an image by the above method on a photosensitive layer or a screen, and to enlarge and project the image using the first and second imaging optical systems. In this proposal, the size of the image projected on the photosensitive layer and the screen is enlarged, while the light from each picture element of the spatial light modulator is condensed by each microlens of the microlens array. The pixel size (spot size) in the projected image is reduced and kept small, and the sharpness of the image can be kept high.

  On the other hand, an exposure apparatus using a DMD as the spatial light modulation element and combining the DMD and a microlens array has been proposed (see Patent Document 2). Further, in the same type of exposure apparatus, an aperture plate having an aperture corresponding to each microlens of the microlens array is arranged on the rear side of the microlens array, and only the light that has passed through the corresponding microlens. An exposure apparatus has been proposed that passes through the opening (see Patent Document 3). In these cases, the extinction ratio can be increased by preventing light from entering from adjacent microlenses that do not correspond to the openings of the aperture plate.

  However, these proposals have a problem that an image formed on the photosensitive layer by using the light condensed by each microlens of the microlens array is distorted. This problem is particularly noticeable when the DMD is used as a spatial light modulator.

  On the other hand, as the resist ink for forming the photosensitive layer, phthalocyanine green is used as a colorant in order to form a protective film exhibiting a green color that is excellent in visibility at the time of inspection and does not irritate the operator's vision. Yes. However, phthalocyanine green contains a high proportion of halogen, and there is a problem that a large amount of toxic gas is generated during combustion when discarded. Therefore, a resist ink containing a pigment that does not contain a halogen atom and that has a coating property (chemical resistance, heat resistance, electrical insulation, hardness, etc.) equivalent to that when using conventional phthalocyanine green is obtained. It has been proposed (see Patent Documents 4 to 8).

  However, both of these proposals have a problem that the photosensitive layer is formed by applying the resist ink on a substrate to be processed and then drying, and thus handling is complicated, and the sensitivity is generally inferior to that of a film-like resist material. is there.

  Therefore, it is possible to form a cured film that has excellent film characteristics and does not generate toxic gas during incineration, and suppresses distortion of an image formed on the photosensitive layer, thereby providing a permanent pattern such as an insulating film or a protective film. However, a permanent pattern forming method capable of forming high-definition efficiently and with high definition has not yet been provided, and the present situation is that further improved development is desired.

JP 2004-1244 A JP 2001-305663 A Special table 2001-500628 gazette JP 2000-7974 A JP 2000-232264 A JP 2001-324801 A Japanese Patent Laid-Open No. 2001-354885 JP 2003-114524 A Akihito Ishikawa "Development shortening and mass production application by maskless exposure", "Electrotronics packaging technology", Technical Research Committee, Vol.18, No.6, 2002, p.74-79

An object of the present invention is to solve the conventional problems and achieve the following objects.
That is, the present invention is capable of forming a cured film that has excellent film properties and does not generate toxic gas during incineration, and suppresses distortion of an image formed on the photosensitive layer, thereby including a print including a package substrate. An object of the present invention is to provide a permanent pattern forming method capable of efficiently and finely forming a permanent pattern (a protective film such as an interlayer insulating film or a solder resist pattern) in the field of wiring boards.

Means for solving the problems are as follows. That is,
<1> A substrate using a photosensitive composition containing at least a binder, a polymerizable compound, a photopolymerization initiator, a thermal crosslinking agent, and a colorant, wherein the colorant is substantially free of halogen atoms. After forming a photosensitive layer on the surface of the photosensitive layer,
After modulating the light from the light irradiating means by the light modulating means having n picture elements for receiving and emitting the light from the light irradiating means, it is possible to correct aberration due to the distortion of the exit surface in the picture element. A method for forming a permanent pattern, characterized by exposing and developing through a microlens array in which microlenses having aspherical surfaces are arranged.
In the method for forming a permanent pattern according to <1>, the light irradiation unit irradiates light toward the light modulation unit. The n picture elements in the light irradiation means receive and emit light from the light irradiation means, thereby modulating the light received from the light irradiation means. The light modulated by the light modulation means passes through the aspherical surface in the microlens array, so that the aberration due to the distortion of the exit surface in the pixel portion is corrected, and the image formed on the photosensitive layer is distorted. It is suppressed. As a result, the photosensitive layer is exposed with high definition. Thereafter, the photosensitive layer is developed to form a high-definition permanent pattern.
Moreover, in the pattern formation method as described in <1>, since the coloring agent contained in the photosensitive composition does not contain a halogen atom, no toxic gas is generated during incineration.
<2> A photosensitive composition containing at least a binder, a polymerizable compound, a photopolymerization initiator, a thermal cross-linking agent, and a colorant, wherein the colorant substantially does not contain a halogen atom. After forming the photosensitive layer on the surface of the material,
A lens that does not allow light from the peripheral part of the picture element part to be incident after the light from the light irradiation part is modulated by a light modulation part having n picture element parts that receive and emit light from the light irradiation means It is a permanent pattern forming method characterized by exposing through a microlens array in which microlenses having aperture shapes are arranged and developing. In the method for forming a permanent pattern according to <2>, the light irradiation unit irradiates light toward the light modulation unit. The n picture elements in the light irradiation means receive and emit light from the light irradiation means, thereby modulating the light received from the light irradiation means. The light modulated by the light modulating means passes through a microlens array in which microlenses having a lens opening shape that does not allow light from the peripheral portion of the pixel portion to enter, so that the peripheral portion of the pixel portion having a large distortion, In particular, the light reflected at the four corners is not collected, and the collected light can be prevented from being distorted. As a result, the photosensitive layer is exposed with high definition. For example, after that, the photosensitive layer is developed to form a high-definition permanent pattern.
Moreover, in the pattern formation method as described in <2>, since the coloring agent contained in the photosensitive composition does not contain a halogen atom, no toxic gas is generated during incineration.
<3> The method for forming a permanent pattern according to <2>, wherein the microlens has an aspherical surface capable of correcting an aberration due to distortion of the exit surface in the pixel part. In the <3> permanent pattern forming method, the light modulated by the light modulation means passes through the aspherical surface in the microlens array, thereby correcting the aberration due to the distortion of the exit surface in the pixel portion, Distortion of an image formed on the exposed surface of the photosensitive layer is suppressed. As a result, the photosensitive layer is exposed with high definition. For example, after that, the photosensitive layer is developed to form a high-definition permanent pattern.
<4> The permanent pattern forming method according to any one of <1> and <3>, wherein the aspherical surface is a toric surface. In the permanent pattern forming method according to <4>, since the aspherical surface is a toric surface, the aberration due to the distortion of the radiation surface in the pixel portion is efficiently corrected, and an image is formed on the pattern forming material. Image distortion is efficiently suppressed. As a result, the photosensitive layer is exposed with high definition. For example, after that, the photosensitive layer is developed to form a high-definition permanent pattern.
<5> The pattern forming method according to any one of <2> to <4>, wherein the lens opening shape is circular.
<6> The pattern forming method according to any one of <2> to <5>, wherein the lens opening shape is defined by providing a light shielding portion on the lens surface.

<7> The method for forming a permanent pattern according to any one of <1> to <6>, wherein the colorant is a phthalocyanine pigment. In the pattern forming method of <7>, since the colorant is a phthalocyanine pigment having a structure similar to that of chlorine-based phthalocyanine green, it is equivalent to the case of using a conventional chlorine-based phthalocyanine green in forming a permanent pattern. Cost and film properties (chemical resistance, heat resistance, electrical insulation, adhesion, hardness, etc.) can be realized.
<8> The method for forming a permanent pattern according to any one of <1> to <7>, wherein the halogen content of the photosensitive layer is less than 900 ppm.
<9> The method for forming a permanent pattern according to any one of <1> to <8>, wherein the formation of the photosensitive layer is performed by applying a photosensitive composition to a surface of a substrate and drying.
<10> A photosensitive film having a support and a photosensitive layer obtained by laminating a photosensitive composition on the support is formed on a substrate under at least one of heating and pressurization. The method for forming a permanent pattern according to any one of <1> to <8>, wherein the method is performed by laminating on a surface. In the method for forming a permanent pattern according to <10>, the photosensitive film having the support and a photosensitive layer obtained by laminating a photosensitive composition on the support is at least either heated or pressurized. It is laminated | stacked on the surface of the said base material under this. As a result, the photosensitive layer is formed on the substrate.
<11> The method for forming a permanent pattern according to <10>, wherein the support includes a synthetic resin and is transparent.
<12> The method for forming a permanent pattern according to any one of <10> to <11>, wherein the support has a long shape.
<13> The method for forming a permanent pattern according to any one of <10> to <12>, wherein the photosensitive film is long and wound in a roll.
<14> The method for forming a permanent pattern according to any one of <10> to <13>, wherein the photosensitive film has a protective film on the photosensitive layer.
<15> The method for forming a permanent pattern according to any one of <1> to <14>, wherein the photosensitive layer has a thickness of 3 to 100 μm.
<16> The permanent pattern forming method according to any one of <1> to <15>, wherein the base material is a printed wiring board on which wiring is formed. In the permanent pattern forming method according to <16>, since the base material is a printed wiring board on which wiring has been formed, by using the permanent pattern forming method, a multilayer wiring board or build-up of a semiconductor or a component can be performed. High-density mounting on a wiring board or the like is possible.

<17> The <1> to <16, wherein the light modulation unit is capable of controlling any less than n pixel elements arranged continuously from n pixel elements in accordance with pattern information. The permanent pattern forming method according to any one of the above. In the method for forming a permanent pattern according to <17>, any less than n pixel parts arranged continuously from n pixel parts in the light modulation unit are controlled according to pattern information. By doing so, the light from the light irradiation means is modulated at high speed.
<18> The permanent pattern formation method according to any one of <1> to <17>, wherein the light modulation unit is a spatial light modulation element.
<19> The method for forming a permanent pattern according to <18>, wherein the spatial light modulation element is a digital micromirror device (DMD).
<20> The method for forming a permanent pattern according to any one of <1> to <19>, wherein the exposure is performed through an aperture array. In the method for forming a permanent pattern according to <20>, the extinction ratio is improved by performing exposure through the aperture array. As a result, the exposure is performed with extremely high definition. Thereafter, the photosensitive layer is developed to form a very fine permanent pattern.
<21> The method for forming a permanent pattern according to any one of <1> to <20>, wherein the exposure is performed while relatively moving the exposure light and the photosensitive layer. In the permanent pattern forming method according to <21>, exposure is performed at a high speed by performing exposure while relatively moving the modulated light and the photosensitive layer.
<22> The permanent pattern forming method according to any one of <1> to <21>, wherein the light irradiation unit can synthesize and irradiate two or more lights. In the method for forming a permanent pattern according to <22>, the light irradiation unit can synthesize and irradiate two or more lights, so that exposure is performed with exposure light having a deep focal depth. As a result, the exposure of the photosensitive layer is performed with extremely high definition. Thereafter, the photosensitive layer is developed to form a very fine permanent pattern.
<23> The light irradiation means includes a plurality of lasers, a multimode optical fiber, and a collective optical system that collects laser beams irradiated from the plurality of lasers and couples them to the multimode optical fiber. <1> to the permanent pattern forming method according to any one of <22>. In the method for forming a permanent pattern according to <23>, the laser light emitted from each of the plurality of lasers is condensed by the collective optical system by the light irradiation unit and can be coupled to the multimode optical fiber. By doing so, exposure is performed with exposure light having a deep focal depth. As a result, the exposure of the photosensitive layer is performed with extremely high definition. Thereafter, the photosensitive layer is developed to form a very fine permanent pattern.
<24> The method for forming a permanent pattern according to <23>, wherein the laser beam has a wavelength of 395 to 415 nm.
<25> The permanent pattern forming method according to any one of <1> to <24>, wherein the photosensitive layer is subjected to a curing treatment after development. In the permanent pattern forming method according to <25>, after the development, the curing treatment is performed on the photosensitive layer. As a result, the film strength of the cured region of the photosensitive layer is increased.
<26> The method for forming a permanent pattern according to <25>, wherein the curing treatment is at least one of a whole surface exposure treatment and a whole surface heat treatment performed at 120 to 200C. In the permanent pattern forming method described in <26>, curing of the resin in the photosensitive composition is promoted in the overall exposure process. Moreover, the film | membrane intensity | strength of a cured film is raised in the whole surface heat processing performed on the said temperature conditions.
<27> The method for forming a permanent pattern according to any one of <1> to <26>, wherein at least one of a protective film and an interlayer insulating film is formed. In the permanent pattern forming method according to <27>, since at least one of the protective film and the interlayer insulating film is formed, the wiring may be subjected to external impact or bending due to the insulating property, heat resistance, etc. of the film. Protected from.

  According to the present invention, conventional problems can be solved, a cured film that is excellent in film characteristics and does not generate toxic gas during incineration, and suppresses distortion of an image formed on the photosensitive layer. By doing so, it is possible to provide a permanent pattern forming method capable of efficiently and precisely forming a permanent pattern (a protective film such as an interlayer insulating film or a solder resist pattern) in the printed wiring board field including a package substrate.

(Permanent pattern forming method)
The permanent pattern forming method of the present invention includes at least an exposure step and a development step, preferably includes a curing treatment step, and further includes other steps appropriately selected as necessary.

[Exposure process]
The exposure step comprises modulating the light from the light irradiating means by means of a light modulating means having n picture elements for receiving and emitting light from the light irradiating means on the photosensitive layer. In this step, exposure is performed through a microlens array in which microlenses having aspherical surfaces capable of correcting aberration due to distortion of the exit surface are arranged.

-Light modulation means-
The light modulation means is not particularly limited as long as it has n picture elements, and can be appropriately selected according to the purpose. For example, a spatial light modulation element is preferably exemplified.
Examples of the spatial light modulator include a digital micromirror device (DMD), a MEMS (Micro Electro Mechanical Systems) type spatial light modulator (SLM), and modulates transmitted light by an electro-optic effect. An optical element (PLZT element), a liquid crystal optical shutter (FLC), etc. are mentioned, Among these, DMD is mentioned suitably.

Hereinafter, an example of the light modulation means will be described with reference to the drawings.
As shown in FIG. 1, in the DMD 50, a large number (eg, 1024 × 768) of micromirrors (micromirrors) 62, each constituting a pixel (pixel), are arranged in a lattice pattern on an SRAM cell (memory cell) 60. It is a mirror device arranged. In each pixel, a micromirror 62 supported by a support column is provided at the top, and a material having high reflectance such as aluminum is deposited on the surface of the micromirror 62. The reflectance of the micromirror 62 is 90% or more, and the arrangement pitch is 13.7 μm as an example in both the vertical and horizontal directions. A silicon gate CMOS SRAM cell 60 manufactured in a normal semiconductor memory manufacturing line is disposed directly below the micromirror 62 via a support including a hinge and a yoke, and the entire structure is monolithic. ing.

  When a digital signal is written in the SRAM cell 60 of the DMD 50, the micromirror 62 supported by the support is tilted in a range of ± α degrees (for example, ± 12 degrees) with respect to the substrate side on which the DMD 50 is disposed with the diagonal line as the center. It is done. 2A shows a state where the micromirror 62 is tilted to + α degrees when the micromirror 62 is in the on state, and FIG. 2B shows a state where the micromirror 62 is tilted to −α degrees when the micromirror 62 is in the off state. Therefore, by controlling the inclination of the micromirror 62 in each pixel of the DMD 50 according to the pattern information as shown in FIG. The

  FIG. 1 shows an example of a state in which a part of the DMD 50 is enlarged and the micromirror 62 is controlled to + α degrees or −α degrees. On / off control of each micromirror 62 is performed by the controller 302 connected to the DMD 50. Further, a light absorber (not shown) is arranged in the direction in which the laser beam B reflected by the off-state micromirror 62 travels.

  Further, it is preferable that the DMD 50 is arranged with a slight inclination so that the short side forms a predetermined angle θ (for example, 0.1 ° to 5 °) with the sub-scanning direction. 3A shows the scanning trajectory of the reflected light image (exposure beam) 53 by each micromirror when the DMD 50 is not tilted, and FIG. 3B shows the scanning trajectory of the exposure beam 53 when the DMD 50 is tilted. Show.

In the DMD 50, a number of micromirror arrays in which a number of micromirrors are arranged in the longitudinal direction (for example, 1024) are arranged in a short direction (for example, 756 pairs). as shown, by tilting the DMD 50, the pitch P ₁ of the scanning locus of the exposure beams 53 from each micromirror (scan line), it becomes narrower than the pitch P ₂ of the scanning lines in the case of not tilting the DMD 50, significant resolution Can be improved. On the other hand, the inclination angle of the DMD 50 is small, the scanning width _{W 2} in the case of tilting the DMD 50, which is substantially equal to the scanning width _{W 1} when not inclined DMD 50.

Next, a method for increasing the modulation speed in the optical modulation means (hereinafter referred to as “high-speed modulation”) will be described.
It is preferable that the light modulation means can control any less than n pixel parts arranged continuously from the n picture elements according to pattern information. There is a limit to the data processing speed of the light modulation means, and the modulation speed per line is determined in proportion to the number of pixels to be used. By using, the modulation speed per line is increased.

Hereinafter, the high-speed modulation will be further described with reference to the drawings.
When the DMD 50 is irradiated with the laser beam B from the fiber array light source 66, the laser beam reflected when the micromirror of the DMD 50 is in an on state is imaged on the photosensitive layer 150 by the lens systems 54 and 58. In this manner, the laser light emitted from the fiber array light source 66 is turned on / off for each pixel, and the photosensitive layer 150 is exposed with pixel units (exposure area 168) of approximately the same number as the number of used pixels of the DMD 50. Further, when the photosensitive layer 150 is moved at a constant speed together with the stage 152, the photosensitive layer 150 is sub-scanned in the direction opposite to the stage moving direction by the scanner 162, and a strip-shaped exposed area 170 is formed for each exposure head 166. Is done.

  In this example, as shown in FIGS. 4A and 4B, the DMD 50 has 768 micromirror arrays in which 1024 micromirrors are arrayed in the main scanning direction. In this example, the controller 302 performs control so that only a part of micromirror rows (eg, 1024 × 256 rows) are driven.

  In this case, a micromirror array arranged at the center of the DMD 50 as shown in FIG. 4 (A) may be used, and a micromirror arranged at the end of the DMD 50 as shown in FIG. 4 (B). A column may be used. In addition, when a defect occurs in some of the micromirrors, the micromirror array to be used may be appropriately changed depending on the situation, such as using a micromirror array in which no defect has occurred.

  Since the data processing speed of the DMD 50 is limited and the modulation speed per line is determined in proportion to the number of pixels used, the modulation speed per line can be increased by using only a part of the micromirror array. Get faster. On the other hand, in the case of an exposure method in which the exposure head is continuously moved relative to the exposure surface, it is not necessary to use all the pixels in the sub-scanning direction.

  When the sub-scan of the photosensitive layer 150 by the scanner 162 is finished and the rear end of the photosensitive layer 150 is detected by the sensor 164, the stage 152 is moved to the uppermost stream side of the gate 160 along the guide 158 by the stage driving device 304. It returns to a certain origin, and again moves along the guide 158 from the upstream side to the downstream side of the gate 160 at a constant speed.

  For example, when only 384 sets of 768 sets of micromirror arrays are used, modulation can be performed twice as fast per line as compared with the case of using all 768 sets. Also, when only 256 pairs are used in the 768 sets of micromirror arrays, modulation can be performed three times faster per line than when all 768 sets are used.

  As described above, according to the permanent pattern forming method of the present invention, the micromirror array in which 1,024 micromirrors are arranged in the main scanning direction includes the DMD in which 768 sets are arranged in the subscanning direction. By controlling so that only a part of the micromirror rows are driven by the controller, the modulation speed per line becomes faster than when all the micromirror rows are driven.

  In addition, an example in which the DMD micromirror is partially driven has been described, but the length of the direction corresponding to the predetermined direction is reflected on the substrate longer than the length of the direction intersecting the predetermined direction according to the control signal. Even if a long and narrow DMD in which a large number of micromirrors capable of changing the surface angle are arranged in a two-dimensional manner is used, the number of micromirrors for controlling the angle of the reflecting surface is reduced. Can do.

  The exposure method is preferably performed while relatively moving the exposure light and the photosensitive layer. In this case, it is preferable to use the exposure light in combination with the high-speed modulation. Thereby, high-speed exposure can be performed in a short time.

  In addition, as shown in FIG. 5, the entire surface of the photosensitive layer 150 may be exposed by a single scan in the X direction by the scanner 162, and as shown in FIGS. After scanning the photosensitive layer 150 in the X direction, the scanner 162 is moved one step in the Y direction, and scanning in the X direction is repeated, so that the entire surface of the photosensitive layer 150 is scanned by a plurality of scans. You may make it expose. In this example, the scanner 162 includes 18 exposure heads 166. Note that the exposure head includes at least the light irradiation unit and the light modulation unit.

  The exposure is performed on a partial area of the photosensitive layer to cure the partial area, and uncured areas other than the cured partial area are removed in a development step described later. A permanent pattern is formed.

Next, an example of a pattern forming apparatus including the light modulation means will be described with reference to the drawings.
As shown in FIG. 7, the pattern forming apparatus including the light modulation means includes a flat plate stage 152 that holds and holds a sheet-like photosensitive film having a photosensitive layer 150 on the surface.
Two guides 158 extending along the stage moving direction are installed on the upper surface of the thick plate-shaped installation table 156 supported by the four legs 154. The stage 152 is arranged so that the longitudinal direction thereof faces the stage moving direction, and is supported by a guide 158 so as to be reciprocally movable. The pattern forming apparatus has a drive device (not shown) for driving the stage 152 along the guide 158.

  A U-shaped gate 160 is provided at the center of the installation table 156 so as to straddle the movement path of the stage 152. Each of the ends of the U-shaped gate 160 is fixed to both side surfaces of the installation table 156. A scanner 162 is provided on one side of the gate 160, and a plurality of (for example, two) detection sensors 164 for detecting the front and rear ends of the photosensitive layer 150 are provided on the other side. The scanner 162 and the detection sensor 164 are respectively attached to the gate 160 and fixedly arranged above the moving path of the stage 152. The scanner 162 and the detection sensor 164 are connected to a controller (not shown) that controls them.

As shown in FIGS. 8 and 9B, the scanner 162 includes a plurality of (for example, 14) exposure heads 166 arranged in a substantially matrix of m rows and n columns (for example, 3 rows and 5 columns). ing. In this example, four exposure heads 166 are arranged in the third row in relation to the width of the photosensitive layer 150. In addition, when showing each exposure head arranged in the m-th row and the n-th column, it is expressed as an exposure head 166 _mn .

An exposure area 168 by the exposure head 166 has a rectangular shape with a short side in the sub-scanning direction. Therefore, as the stage 152 moves, a strip-shaped exposed area 170 is formed for each exposure head 166 in the photosensitive layer 150. In addition, when showing the exposure area by each exposure head arranged in the m-th row and the n-th column, it is expressed as an exposure area 168 _mn .

Further, as shown in FIGS. 9A and 9B, each of the exposure heads in each row arranged in a line so that the strip-shaped exposed regions 170 are arranged in the direction orthogonal to the sub-scanning direction without gaps. These are arranged with a predetermined interval (natural number times the long side of the exposure area, twice in this example) in the arrangement direction. Therefore, can not be exposed portion between the exposure area _{168 11} in the first row and the exposure area _{168 12,} it can be exposed by the second row of the exposure area _{168 21} and the exposure area _{168 31} in the third row.

As shown in FIGS. 10 and 11, each of the exposure heads 166 _{11 to} 166 _mn serves as the light modulation means (spatial light modulation element that modulates each pixel) according to the pattern information. A digital micromirror device (DMD) 50 manufactured by Texas Instruments, USA is provided. The DMD 50 is connected to a later-described controller 302 (see FIG. 12) having a data processing unit and a mirror drive control unit. The data processing unit of the controller 302 generates a control signal for driving and controlling each micromirror in the area to be controlled by the DMD 50 for each exposure head 166 based on the input pattern information. The area to be controlled will be described later. The mirror drive control unit controls the angle of the reflection surface of each micromirror of the DMD 50 for each exposure head 166 based on the control signal generated by the pattern information processing unit. The control of the angle of the reflecting surface will be described later.

  On the light incident side of the DMD 50, a fiber array light source 66 including a laser emitting section in which emission ends (light emitting points) of an optical fiber are arranged in a line along a direction corresponding to the long side direction of the exposure area 168, a fiber A lens system 67 for correcting the laser light emitted from the array light source 66 and condensing it on the DMD, and a mirror 69 for reflecting the laser light transmitted through the lens system 67 toward the DMD 50 are arranged in this order. In FIG. 10, the lens system 67 is schematically shown.

  As shown in detail in FIG. 11, the lens system 67 is inserted into the optical path of the light passing through the condenser lens 71 and the condenser lens 71 that collects the laser light B as the illumination light emitted from the fiber array light source 66. A rod-shaped optical integrator (hereinafter referred to as a rod integrator) 72 and an imaging lens 74 disposed in front of the rod integrator 72, that is, on the mirror 69 side. The condensing lens 71, the rod integrator 72, and the imaging lens 74 cause the laser light emitted from the fiber array light source 66 to enter the DMD 50 as a light beam that is close to parallel light and has a uniform beam cross-sectional intensity. The shape and action of the rod integrator 72 will be described in detail later.

  The laser beam B emitted from the lens system 67 is reflected by the mirror 69 and irradiated to the DMD 50 via the TIR (total reflection) prism 70. In FIG. 10, the TIR prism 70 is omitted.

  An imaging optical system 51 that images the laser beam B reflected by the DMD 50 on the pattern forming material 150 is disposed on the light reflection side of the DMD 50. The imaging optical system 51 is schematically shown in FIG. 10, but as shown in detail in FIG. 11, the imaging optical system 51 includes a first imaging optical system including lens systems 52 and 54 and lens systems 57 and 58. A second imaging optical system, a microlens array 55 inserted between these imaging optical systems, and an aperture array 59 are included.

The microlens array 55 is formed by two-dimensionally arranging a large number of microlenses 55a corresponding to the pixels of the DMD 50. In this example, as will be described later, only 1024 × 256 rows of the 1024 × 768 rows of micromirrors of the DMD 50 are driven, and accordingly, 1024 × 256 rows of microlenses 55a are arranged. The arrangement pitch of the micro lenses 55a is 41 μm in both the vertical and horizontal directions. As an example, the microlens 55a has a focal length of 0.19 mm, an NA (numerical aperture) of 0.11, and is formed from the optical glass BK7. The shape of the micro lens 55a will be described in detail later.
The beam diameter of the laser beam B at the position of each microlens 55a is 41 μm.

  The aperture array 59 is formed by forming a large number of apertures (openings) 59 a corresponding to the respective micro lenses 55 a of the micro lens array 55. The diameter of the aperture 59a is, for example, 10 μm.

  The first imaging optical system enlarges the image by the DMD 50 three times and forms an image on the microlens array 55. The second imaging optical system enlarges the image that has passed through the microlens array 55 by 1.6 times, and forms and projects the image on the photosensitive layer 150. Therefore, as a whole, the image by the DMD 50 is magnified 4.8 times and is formed and projected on the photosensitive layer 150.

  A prism pair 73 is disposed between the second imaging optical system and the photosensitive layer 150, and the prism pair 73 is moved in the vertical direction in FIG. 11 to focus the image on the photosensitive layer 150. Can be adjusted. In the figure, the photosensitive layer 150 is sub-scanned in the direction of arrow F.

The pixel part is not particularly limited as long as it can receive and emit light from the light irradiation means, and can be appropriately selected according to the purpose. For example, the permanent pattern forming method of the present invention When the permanent pattern formed by the above is an image pattern, it is a pixel, and when the light modulation means includes a DMD, it is a micromirror.
There is no restriction | limiting in particular as the number (the said n) of picture element parts which the said light modulation element has, It can select suitably according to the objective.
The arrangement of the picture element portions in the light modulation element is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is preferably arranged in a two-dimensional form, and arranged in a lattice form. More preferably.

-Micro lens array-
Hereinafter, the microlens array, the aperture array, the imaging optical system, and the like will be described with reference to the drawings.

FIG. 13A shows each of DMD 50, light irradiation means 144 for irradiating the DMD 50 with laser light, lens systems (imaging optical systems) 454, 458, and DMD 50 for enlarging and imaging the laser light reflected by the DMD 50. A microlens array 472 in which a large number of microlenses 474 are arranged corresponding to the picture element portion, an aperture array 476 in which a large number of apertures 478 are provided corresponding to each microlens of the microlens array 472, and a laser that has passed through the aperture An exposure head composed of lens systems (imaging optical systems) 480 and 482 for forming an image of light on an exposed surface 56 is shown.
Here, FIG. 14 shows the result of measuring the flatness of the reflecting surface of the micromirror 62 constituting the DMD 50. In the figure, the same height positions of the reflecting surfaces are shown connected by contour lines, and the pitch of the contour lines is 5 nm. Note that the x direction and the y direction shown in the figure are two diagonal directions of the micromirror 62, and the micromirror 62 rotates around the rotation axis extending in the y direction as described above. 15A and 15B show the height position displacement of the reflecting surface of the micromirror 62 along the x direction and the y direction, respectively.

As shown in FIGS. 14 and 15, there is distortion on the reflection surface of the micromirror 62 of the DMD 50. In particular, when attention is paid to the central part of the mirror, distortion in one diagonal direction (y direction) is different. Is larger than the distortion in the diagonal direction (x direction). For this reason, the problem that the shape in the condensing position of the laser beam B condensed with the micro lens 55a of the micro lens array 55 may be distorted may occur.
The first aspect of the permanent pattern forming method of the present invention is applied to prevent the above problem, and the microlens 55a of the microlens array 55 has a special shape different from the conventional one.

Further, the amount of change in distortion on the reflection surface of the micromirror 62 of the DMD 50 tends to gradually increase from the center of the micromirror 62 toward the peripheral portion. The amount of change in peripheral distortion in one diagonal direction (y direction) of the micromirror 62 is larger than the amount of change in peripheral distortion in another diagonal direction (x direction), and the above-described tendency is more prominent. .
The second aspect of the permanent pattern forming method of the present invention is applied to prevent the above problem, and the microlens 55a of the microlens array 55 receives light from the peripheral portion of the pixel portion. It has a lens aperture shape that is not allowed.

--Microlens array of the first aspect--
There is no restriction | limiting in particular as said aspherical surface, Although it can select suitably according to the objective, For example, a toric surface is preferable.

  FIGS. 16A and 16B respectively show the front and side shapes of the entire microlens array 55 in detail. These drawings also show the dimensions of each part of the microlens array 55, and the unit thereof is mm. In the permanent pattern forming method of the present invention, as described above with reference to FIG. 4, the 1024 × 256 rows of micromirrors 62 of the DMD 50 are driven. A row of 1024 microlenses 55a arranged in the horizontal direction is arranged in parallel in the vertical direction. In FIG. 9A, the arrangement order of the microlens array 55 is indicated by j in the horizontal direction and k in the vertical direction.

  17A and 17B show the front shape and the side shape of one microlens 55a in the microlens array 55, respectively. In FIG. 9A, the contour lines of the micro lens 55a are also shown. The end surface of each microlens 55a on the light emitting side has an aspherical shape that corrects aberration due to distortion of the reflecting surface of the micromirror 62. More specifically, the micro lens 55a is a toric lens, and has a radius of curvature Rx = −0.125 mm in a direction optically corresponding to the x direction and a radius of curvature Ry = − in a direction corresponding to the y direction. 0.1 mm.

  Therefore, the condensing state of the laser beam B in the cross section parallel to the x direction and the y direction is roughly as shown in FIGS. 18A and 18B, respectively. That is, when the cross section parallel to the x direction is compared with the cross section parallel to the y direction, the radius of curvature of the microlens 55a is smaller and the focal length is shorter in the latter cross section. .

  19A, 19B, 19D, and 19D show simulation results of the beam diameter in the vicinity of the condensing position (focal position) of the microlens 55a when the microlens 55a has the above shape. For comparison, FIGS. 20a, 20b, 20c, and 20d show the results of a similar simulation when the microlens 55a has a spherical shape with a radius of curvature Rx = Ry = −0.1 mm. In addition, the value of z in each figure has shown the evaluation position of the focus direction of the micro lens 55a with the distance from the beam emission surface of the micro lens 55a.

The surface shape of the microlens 55a used for the simulation is calculated by the following calculation formula.

  In the above formula, Cx means the curvature in the x direction (= 1 / Rx), Cy means the curvature in the y direction (= 1 / Ry), and X is the lens optical axis in the x direction. The distance from O means Y, and Y means the distance from the lens optical axis O in the y direction.

  19A to 19D and FIG. 20A to FIG. 20D, in the permanent pattern forming method of the present invention, the microlens 55a has a focal length in the cross section parallel to the y direction in the cross section parallel to the x direction. By using a toric lens that is smaller than the focal length, distortion of the beam shape in the vicinity of the condensing position is suppressed. If so, a higher-definition image without distortion can be exposed on the photosensitive layer 150. It can also be seen that the embodiment shown in FIGS. 19a to 19d has a wider region with a smaller beam diameter, that is, a greater depth of focus.

  In addition, when the magnitude relation of the distortion of the central part in the x direction and the y direction of the micromirror 62 is opposite to the above, the focal length in the cross section parallel to the x direction is If the microlens is composed of a toric lens that is smaller than the focal length, similarly, a higher-definition image without distortion can be exposed on the photosensitive layer 150.

  In addition, the aperture array 59 disposed in the vicinity of the condensing position of the microlens array 55 is disposed such that only light having passed through the corresponding microlens 55a is incident on each aperture 59a. That is, by providing this aperture array 59, it is possible to prevent light from adjacent microlenses 55a not corresponding to each aperture 59a from entering, and to increase the extinction ratio.

  Originally, if the diameter of the aperture 59a of the aperture array 59 installed for the above purpose is reduced to some extent, an effect of suppressing the distortion of the beam shape at the condensing position of the microlens 55a can be obtained. However, in such a case, the amount of light blocked by the aperture array 59 is increased, and the light use efficiency is reduced. On the other hand, when the microlens 55a has an aspherical shape, the light utilization efficiency is kept high because the light is not blocked.

  In the pattern forming method of the present invention, the micro lens 55a which is a toric lens having different curvatures in the x direction and the y direction optically corresponding to the two diagonal directions of the micro mirror 62 is applied. 38A and 38B, the xx direction and yy optically corresponding to the two side directions of the rectangular micromirror 62 are shown in FIGS. A microlens 55a ′ composed of toric lenses having different curvatures in directions may be applied.

  In the permanent pattern forming method of the present invention, the microlens 55a may have a secondary aspherical shape or a higher order (4th, 6th,...) Aspherical shape. . By adopting the higher order aspherical shape, the beam shape can be further refined. Furthermore, it is possible to adopt a lens shape in which the curvatures in the x direction and the y direction described above coincide with each other in accordance with the distortion of the reflection surface of the micromirror 62. Hereinafter, examples of such lens shapes will be described in detail.

39A and 39B, the microlens 55a ″ showing the front shape and the side shape with contour lines, respectively, has the same curvature in the x direction and the y direction, and the curvature is equal to the curvature Cy of the spherical lens. The spherical lens shape that is the basis of the lens shape of the microlens 55a ″ is, for example, the lens height (lens) according to the following equation (Equation 2). A curved surface in which the position in the optical axis direction) z is defined is adopted.
FIG. 40 is a graph showing the relationship between the lens height z and the distance h when the curvature Cy = (1 / 0.1 mm).

Then, the curvature Cy of the spherical lens shape is corrected according to the following formula (Equation 3) in accordance with the distance h from the lens center to obtain the lens shape of the microlens 55a ″.

Also in the calculation formula (Formula 3), the meaning of z is the same as the above-described calculation formula (Formula 2). Here, the curvature Cy is corrected using the fourth-order coefficient a and the sixth-order coefficient b. . The lens height z and the distance h when the curvature Cy = (1 / 0.1 mm), the fourth-order coefficient a = 1.2 × 10 ³ , and the sixth-order coefficient a = 5.5 × 10 ⁷ are described. The relationship is shown in a graph in FIG.

  In the embodiment described above, the end surface on the light emission side of the micro lens 55a is an aspherical surface (toric surface). However, one of the two light passing end surfaces is a spherical surface and the other is a cylindrical surface. Thus, the microlens array can be configured to obtain the same effect as the above embodiment.

  Furthermore, in the embodiment described above, the microlens 55a of the microlens array 55 has an aspherical shape that corrects aberration due to distortion of the reflecting surface of the micromirror 62. Such an aspherical shape is adopted. Instead, the same effect can be obtained even if each microlens constituting the microlens array has a refractive index distribution that corrects aberration due to distortion of the reflection surface of the micromirror 62.

  An example of such a microlens 155a is shown in FIG. (A) and (B) of the same figure respectively show the front shape and side shape of the micro lens 155a, and the external shape of the micro lens 155a is a parallel plate shape as shown in the figure. The x and y directions in the figure are as described above.

  23A and 23B schematically show the condensing state of the laser beam B in the cross section parallel to the x direction and the y direction by the micro lens 155a. The microlens 155a has a refractive index distribution that gradually increases outward from the optical axis O. In the drawing, the broken line shown in the microlens 155a indicates that the refractive index is predetermined from the optical axis O. The position changed with the pitch is shown. As shown in the figure, when the cross section parallel to the x direction and the cross section parallel to the y direction are compared, the ratio of the refractive index change of the microlens 155a is larger in the latter cross section, and the focal length is larger. It is shorter. Even when a microlens array composed of such a gradient index lens is used, it is possible to obtain the same effect as when the microlens array 55 is used.

  In addition, in the microlens whose surface shape is aspherical like the microlens 55a previously shown in FIGS. 17 and 18, the refractive index distribution as described above is given together, and both by the surface shape and the refractive index distribution. The aberration due to the distortion of the reflection surface of the micromirror 62 may be corrected.

--Microlens array of second aspect--
As shown in FIG. 42, the microlens array of the second aspect is formed by arranging microlenses having a lens opening shape that does not allow the light from the peripheral portion of the picture element portion to enter.

  In the microlens array 255, microlenses 255a arranged in an array form have circular lens openings. Therefore, as described above, the laser light B reflected at the peripheral portion of the reflecting surface of the micromirror 62 having a large distortion, particularly at the four corners, is not condensed by the microlens 255a, and the condensing position of the condensed laser light B is reduced. Can be prevented from being distorted. Therefore, a higher-definition image without distortion can be exposed to the pattern forming material 150.

  In the microarray 255, as shown in FIG. 42, the back surface of the transparent member 255b holding the microlens 255a (which is usually formed integrally with the microlens 255a), that is, the microlens 255a is formed. A light-shielding mask 255c is formed in a state where the outer region of the lens openings of the plurality of microlenses 255a that are separated from each other is filled in the surface opposite to the surface that is formed. By providing such a mask 255c, the laser beam B reflected at the periphery of the reflecting surface of the micromirror 62, particularly at the four corners, is absorbed and blocked there, so the shape of the focused laser beam B Is more reliably prevented from being distorted.

  In the microarray 255, the opening shape of the microlens is not limited to the circular shape described above. For example, as shown in FIG. As shown in FIG. 44, a microlens array 555 in which a plurality of microlenses 555a having polygonal (rectangular in the illustrated example) openings are arranged side by side can also be applied. The microlenses 455a and 555a are formed by cutting out a part of a normal axisymmetric spherical lens into a circular shape or a polygonal shape, and have a light collecting function similar to that of a normal axisymmetric spherical lens.

  Furthermore, in the microlens array of the second aspect, it is also possible to apply a microlens array as shown in FIGS. 45 (A), (B) and (C). The microlens array 655 shown in FIG. 6A is such that a plurality of microlenses 655a similar to the microlenses 55a, 455a, and 555a are in close contact with the surface of the transparent member 655b on the side where the laser beam B is emitted. A mask 655c similar to the mask 255c is formed on the surface on the side where the laser beam B is incident. Note that the mask 255c in FIG. 42 is formed in the outer portion of the lens opening, whereas the mask 655c is provided in the lens opening. In the microlens array 755 shown in FIG. 5B, a plurality of microlenses 755a are arranged in parallel with each other on the surface of the transparent member 455b on the side where the laser beam B is emitted, and the microlens 755a is disposed between the microlenses 755a. Then, a mask 755c is formed. In the microlens array 855 shown in FIG. 5C, a plurality of microlenses 855a are arranged in parallel with each other on the surface of the transparent member 855b on the side where the laser beam B is emitted, and the periphery of each microlens 855a is arranged. A mask 855c is formed on the portion.

  The masks 655c, 755c, and 855c all have a circular opening as in the above-described mask 255c, so that the opening of the microlens is defined as a circle.

  FIG. 17 shows a configuration in which a lens opening shape that does not allow light from the periphery of the micromirror 62 of the DMD 50 to enter by providing a mask, such as the microlenses 255a, 455a, 555a, 655a, and 755a described above. An aspherical lens that corrects aberration due to the distortion of the surface of the micromirror 62 like the microlens 55a described above, or a lens having a refractive index distribution that corrects the aberration like the microlens 155a shown in FIG. It is also possible to employ them. By doing so, the effect of preventing the distortion of the exposure image due to the distortion of the reflection surface of the micromirror 62 is synergistically enhanced.

  In particular, in the configuration in which the mask 855c is formed on the lens surface of the microlens 855a in the microlens array 855 as shown in FIG. 45C, the microlens 855a has the above-mentioned aspherical shape and refractive index distribution. In addition, for example, when the imaging position of the first imaging optical system such as the lens systems 52 and 54 shown in FIG. 11 is set on the lens surface of the microlens 855a, the light is particularly light. The utilization efficiency is increased, and the pattern forming material 150 can be exposed with higher intensity light. That is, at that time, the first imaging optical system refracts the light so that stray light due to the distortion of the reflection surface of the micromirror 62 is focused at one point at the imaging position of the optical system. If the mask 855c is formed, light other than stray light is not shielded, and light use efficiency is improved.

  In the microlens array of the first aspect and the microlens array of the second aspect, the aberration due to the distortion of the reflection surface of the micromirror 62 constituting the DMD 50 is corrected, but the spatial light modulation element other than the DMD Also in the permanent pattern forming method of the present invention using the present invention, if there is distortion on the surface of the picture element portion of the spatial light modulator, the present invention is applied to correct the aberration due to the distortion and the beam shape is distorted. It can be prevented from occurring.

-Imaging optics-
Next, the imaging optical system will be further described.
In the exposure head, when the laser beam is irradiated from the light irradiation unit 144, the cross-sectional area of the light beam reflected in the ON direction by the DMD 50 is enlarged several times (for example, two times) by the lens systems 454 and 458. The The expanded laser light is condensed by each microlens of the microlens array 472 so as to correspond to each pixel part of the DMD 50, and passes through the corresponding aperture of the aperture array 476. The laser light that has passed through the aperture is imaged on the exposed surface 56 by the lens systems 480 and 482.

  In this imaging optical system, the laser light reflected by the DMD 50 is magnified several times by the magnifying lenses 454 and 458 and projected onto the exposed surface 56, so that the entire image area is widened. At this time, if the microlens array 472 and the aperture array 476 are not arranged, as shown in FIG. 13B, one pixel size (spot size) of each beam spot BS projected onto the exposed surface 56 is set. MTF (Modulation Transfer Function) characteristics representing the sharpness of the exposure area 468 are reduced depending on the size of the exposure area 468.

  On the other hand, when the microlens array 472 and the aperture array 476 are arranged, the laser light reflected by the DMD 50 is condensed corresponding to each pixel part of the DMD 50 by each microlens of the microlens array 472. Accordingly, as shown in FIG. 13C, even when the exposure area is enlarged, the spot size of each beam spot BS can be reduced to a desired size (for example, 10 μm × 10 μm), and the MTF characteristics are obtained. It is possible to perform high-definition exposure while preventing a decrease in the image quality. The exposure area 468 is tilted because the DMD 50 is tilted and arranged in order to eliminate the gap between the pixels.

  In addition, the aperture array can shape the beam so that the spot size on the surface to be exposed 56 is constant even if the beam is thick due to the aberration of the micro lens. Thus, crosstalk between adjacent picture elements can be prevented by passing through the aperture array.

  Further, by using a high-intensity light source, which will be described later, as the light irradiating means 144, the angle of the light beam incident on each microlens of the microlens array 472 from the lens 458 becomes small. The incident can be prevented. That is, a high extinction ratio can be realized.

-Other optical systems-
In the permanent pattern forming method of the present invention, it may be used in combination with other optical systems appropriately selected from known optical systems, for example, a light quantity distribution correcting optical system composed of a pair of combination lenses.
The light amount distribution correcting optical system changes the light flux width at each exit position so that the ratio of the light flux width at the peripheral portion to the light flux width at the central portion close to the optical axis is smaller on the exit side than on the incident side. When the DMD is irradiated with the parallel light flux from the light irradiation means, the light amount distribution on the irradiated surface is corrected so as to be substantially uniform. Hereinafter, the light quantity distribution correcting optical system will be described with reference to the drawings.

  First, as shown in FIG. 24A, the case where the entire luminous flux widths (total luminous flux widths) H0 and H1 are the same for the incident luminous flux and the outgoing luminous flux will be described. In FIG. 24A, the portions denoted by reference numerals 51 and 52 virtually indicate the entrance surface and the exit surface in the light quantity distribution correction optical system.

  In the light quantity distribution correcting optical system, it is assumed that the light flux widths h0 and h1 of the light beam incident on the central portion near the optical axis Z1 and the light flux incident on the peripheral portion are the same (h0 = hl). The light quantity distribution correcting optical system expands the light flux width h0 of the incident light flux at the central portion with respect to the light having the same light flux width h0, h1 on the incident side, and conversely changes the incident light flux at the peripheral portion. On the other hand, the light beam width h1 is reduced. That is, the width h10 of the outgoing light beam at the center and the width h11 of the outgoing light beam at the periphery are set to satisfy h11 <h10. In terms of the ratio of the luminous flux width, the ratio “h11 / h10” of the luminous flux width in the peripheral portion to the luminous flux width in the central portion on the emission side is smaller than the ratio (h1 / h0 = 1) on the incident side ( (H11 / h10) <1).

  By changing the light flux width in this way, the light flux in the central part, which normally has a large light quantity distribution, can be utilized in the peripheral part where the light quantity is insufficient, and the overall light utilization efficiency is not reduced. In addition, the light quantity distribution on the irradiated surface is made substantially uniform. The degree of uniformity is, for example, such that the unevenness in the amount of light in the effective area is within 30%, preferably within 20%.

  The actions and effects of the light quantity distribution correcting optical system are the same when the entire luminous flux width is changed between the incident side and the exit side (FIGS. 24B and 24C).

  FIG. 24B shows a case where the entire light flux width H0 on the incident side is “reduced” to the width H2 and emitted (H0> H2). Even in such a case, the light quantity distribution correcting optical system has the same light beam width h0, h1 on the incident side, and the light beam width h10 in the central part is larger than that in the peripheral part on the emission side. Conversely, the luminous flux width h11 at the peripheral part is made smaller than that at the central part. Considering the reduction rate of the light beam, the reduction rate with respect to the incident light beam in the central part is made smaller than that in the peripheral part, and the reduction rate with respect to the incident light beam in the peripheral part is made larger than that in the central part. Also in this case, the ratio “H11 / H10” of the light flux width in the peripheral portion to the light flux width in the central portion is smaller than the ratio (h1 / h0 = 1) on the incident side ((h11 / h10) <1). .

  FIG. 24C shows a case where the entire light flux width H0 on the incident side is “enlarged” by the width Η3 and emitted (H0 <H3). Even in such a case, the light quantity distribution correcting optical system has the same light beam width h0, h1 on the incident side, and the light beam width h10 in the central part is larger than that in the peripheral part on the emission side. Conversely, the luminous flux width h11 at the peripheral part is made smaller than that at the central part. Considering the expansion rate of the light beam, the expansion rate for the incident light beam in the central portion is made larger than that in the peripheral portion, and the expansion rate for the incident light beam in the peripheral portion is made smaller than that in the central portion. Also in this case, the ratio “h11 / h10” of the light flux width in the peripheral portion to the light flux width in the central portion is smaller than the ratio (h1 / h0 = 1) on the incident side ((h11 / h10) <1). .

  As described above, the light quantity distribution correcting optical system changes the light beam width at each emission position, and the ratio of the light beam width in the peripheral part to the light beam width in the central part near the optical axis Z1 is larger on the outgoing side than on the incident side. Since the light having the same luminous flux width on the incident side is larger on the outgoing side, the luminous flux width in the central portion is larger than that in the peripheral portion, and the luminous flux width in the peripheral portion is smaller than that in the central portion. Become smaller. As a result, it is possible to make use of the light beam at the center part to the peripheral part, and it is possible to form a light beam cross-section with a substantially uniform light amount distribution without reducing the light use efficiency of the entire optical system.

Next, an example of specific lens data of a pair of combination lenses used as the light quantity distribution correcting optical system will be shown. In this example, lens data in the case where the light amount distribution in the cross section of the emitted light beam is a Gaussian distribution as in the case where the light irradiation means is a laser array light source is shown. When one semiconductor laser is connected to the incident end of the single mode optical fiber, the light quantity distribution of the emitted light beam from the optical fiber becomes a Gaussian distribution. The permanent pattern forming method of the present invention can be applied to such a case. Further, the present invention can be applied to a case where the light amount in the central portion near the optical axis is larger than the light amount in the peripheral portion, for example, by reducing the core diameter of the multi-mode optical fiber and approaching the configuration of the single mode optical fiber.
Table 1 below shows basic lens data.

  As can be seen from Table 1, the pair of combination lenses is composed of two rotationally symmetric aspherical lenses. If the light incident side surface of the first lens disposed on the light incident side is the first surface and the light exit side surface is the second surface, the first surface is aspherical. In addition, when the surface on the light incident side of the second lens disposed on the light emitting side is the third surface and the surface on the light emitting side is the fourth surface, the fourth surface is aspherical.

In Table 1, the surface number Si indicates the number of the i-th surface (i = 1 to 4), the curvature radius ri indicates the curvature radius of the i-th surface, and the surface interval di indicates the i-th surface and the i + 1-th surface. The distance between surfaces on the optical axis is shown. The unit of the surface interval di value is millimeter (mm). The refractive index Ni indicates the value of the refractive index with respect to the wavelength of 405 nm of the optical element having the i-th surface.
Table 2 below shows the aspheric data of the first surface and the fourth surface.

  The aspheric data is expressed by a coefficient in the following formula (A) that represents the aspheric shape.

In the above formula (A), each coefficient is defined as follows.
Z: Length of a perpendicular line (mm) drawn from a point on the aspheric surface at a height ρ from the optical axis to the tangent plane (plane perpendicular to the optical axis) of the apex of the aspheric surface
ρ: Distance from optical axis (mm)
K: Conic coefficient C: Paraxial curvature (1 / r, r: Paraxial radius of curvature)
ai: i-th order (i = 3 to 10) aspheric coefficient In the numerical values shown in Table 2, the symbol “E” indicates that the subsequent numerical value is a “power index” with 10 as the base. The numerical value represented by the exponential function with the base of 10 is multiplied by the numerical value before “E”. For example, “1.0E-02” indicates “1.0 × 10 ⁻² ”.

  FIG. 26 shows a light amount distribution of illumination light obtained by the pair of combination lenses shown in Tables 1 and 2. The horizontal axis indicates coordinates from the optical axis, and the vertical axis indicates the light amount ratio (%). For comparison, FIG. 25 shows a light amount distribution (Gaussian distribution) of illumination light when correction is not performed. As can be seen from FIGS. 25 and 26, the light amount distribution correction optical system corrects the light amount distribution which is substantially uniform as compared with the case where the correction is not performed. Thereby, it is possible to perform exposure with uniform laser light without reducing the use efficiency of light, without causing any unevenness.

-Light irradiation means-
The light irradiation means is not particularly limited and may be appropriately selected depending on the purpose. For example, (ultra) high pressure mercury lamp, xenon lamp, carbon arc lamp, halogen lamp, copier, fluorescent tube, LED, etc. , A known light source such as a semiconductor laser, or means capable of synthesizing and irradiating two or more lights. Among these, means capable of synthesizing and irradiating two or more lights are preferable.
The light emitted from the light irradiation means is, for example, an electromagnetic wave that passes through the support and activates the photopolymerization initiator and sensitizer used when the light is irradiated through the support. In particular, ultraviolet to visible light, electron beam, X-ray, laser beam, and the like can be mentioned. Of these, laser beam is preferable, and laser beam obtained by combining two or more beams (hereinafter, referred to as “combined laser beam”). ) Is more preferable. Even when light irradiation is performed after the support is peeled off, the same light can be used.

As a wavelength of the ultraviolet to visible light, for example, 300 to 1500 nm is preferable, 320 to 800 nm is more preferable, and 330 nm to 650 nm is particularly preferable.
As a wavelength of the said laser beam, 200-1500 nm is preferable, for example, 300-800 nm is more preferable, 330 nm-500 nm is still more preferable, 395 nm-415 nm is especially preferable.

  Examples of means capable of irradiating the combined laser beam include a plurality of lasers, a multimode optical fiber, and a set for condensing and coupling the laser beams respectively emitted from the plurality of lasers to the multimode optical fiber. Means having an optical system are preferred.

  Hereinafter, means (fiber array light source) capable of irradiating the combined laser beam will be described with reference to the drawings.

  As shown in FIG. 27 a, the fiber array light source 66 includes a plurality of (for example, 14) laser modules 64, and one end of the multimode optical fiber 30 is coupled to each laser module 64. An optical fiber 31 having the same core diameter as that of the multimode optical fiber 30 and a smaller cladding diameter than the multimode optical fiber 30 is coupled to the other end of the multimode optical fiber 30. As shown in detail in FIG. 27b, seven end portions of the multimode optical fiber 31 opposite to the optical fiber 30 are arranged along the main scanning direction orthogonal to the sub-scanning direction, and they are arranged in two rows to form a laser. An emission unit 68 is configured.

  As shown in FIG. 27b, the laser emitting portion 68 configured by the end portion of the multimode optical fiber 31 is sandwiched and fixed between two support plates 65 having a flat surface. Further, a transparent protective plate such as glass is preferably disposed on the light emitting end face of the multimode optical fiber 31 for protection. The light exit end face of the multimode optical fiber 31 has high light density and is likely to collect dust and easily deteriorate. However, the protective plate as described above prevents the dust from adhering to the end face and deteriorates. Can be delayed.

  In this example, in order to arrange the emission ends of the optical fibers 31 with a small cladding diameter in a line without any gaps, the multimode optical fiber 30 is placed between two adjacent multimode optical fibers 30 at a portion with a large cladding diameter. Two exit ends of the optical fiber 31 coupled to the two multimode optical fibers 30 adjacent to each other at the portion where the cladding diameter is large are the exit ends of the optical fiber 31 coupled to the stacked and stacked multimode optical fibers 30. Are arranged so as to be sandwiched between them.

  For example, as shown in FIG. 28, an optical fiber 31 having a length of 1 to 30 cm and having a small cladding diameter is coaxially connected to the tip portion of the multimode optical fiber 30 having a large cladding diameter on the laser light emission side. Can be obtained by linking them together. In the two optical fibers, the incident end face of the optical fiber 31 is fused and joined to the outgoing end face of the multimode optical fiber 30 so that the central axes of both optical fibers coincide. As described above, the diameter of the core 31 a of the optical fiber 31 is the same as the diameter of the core 30 a of the multimode optical fiber 30.

  In addition, a short optical fiber in which an optical fiber having a short cladding diameter and a large cladding diameter is fused to an optical fiber having a short cladding diameter and a large cladding diameter may be coupled to the output end of the multimode optical fiber 30 via a ferrule or an optical connector. Good. By detachably coupling using a connector or the like, the tip portion can be easily replaced when an optical fiber having a small cladding diameter is broken, and the cost required for exposure head maintenance can be reduced. Hereinafter, the optical fiber 31 may be referred to as an emission end portion of the multimode optical fiber 30.

  The multimode optical fiber 30 and the optical fiber 31 may be any of a step index type optical fiber, a graded index type optical fiber, and a composite type optical fiber. For example, a step index type optical fiber manufactured by Mitsubishi Cable Industries, Ltd. can be used. In the present embodiment, the multimode optical fiber 30 and the optical fiber 31 are step index type optical fibers, and the multimode optical fiber 30 has a cladding diameter = 125 μm, a core diameter = 25 μm, NA = 0.2, an incident end face. The transmittance of the coat is 99.5% or more, and the optical fiber 31 has a cladding diameter = 60 μm, a core diameter = 50 μm, and NA = 0.2.

  In general, in laser light in the infrared region, propagation loss increases as the cladding diameter of the optical fiber is reduced. For this reason, a suitable cladding diameter is determined according to the wavelength band of the laser beam. However, the shorter the wavelength, the smaller the propagation loss. In the case of laser light having a wavelength of 405 nm emitted from a GaN-based semiconductor laser, the cladding thickness {(cladding diameter−core diameter) / 2} is set to an infrared light having a wavelength band of 800 nm. The propagation loss hardly increases even if it is about ½ of the case of propagating infrared light and about ¼ of the case of propagating infrared light in the 1.5 μm wavelength band for communication. Therefore, the cladding diameter can be reduced to 60 μm.

  However, the cladding diameter of the optical fiber 31 is not limited to 60 μm. The clad diameter of the optical fiber used in the conventional fiber array light source is 125 μm, but the depth of focus becomes deeper as the clad diameter becomes smaller. More preferably, it is 40 μm or less. On the other hand, since the core diameter needs to be at least 3 to 4 μm, the cladding diameter of the optical fiber 31 is preferably 10 μm or more.

  The laser module 64 includes a combined laser light source (fiber array light source) shown in FIG. This combined laser light source includes a plurality of (for example, seven) chip-like lateral multimode or single mode GaN-based semiconductor lasers LD1, LD2, LD3, LD4, LD5, LD6, arrayed and fixed on the heat block 10. And LD7, collimator lenses 11, 12, 13, 14, 15, 16, and 17 provided corresponding to each of the GaN-based semiconductor lasers LD1 to LD7, one condenser lens 20, and one multi-lens. Mode optical fiber 30. The number of semiconductor lasers is not limited to seven. For example, as many as 20 semiconductor laser beams can be incident on a multimode optical fiber having a cladding diameter = 60 μm, a core diameter = 50 μm, and NA = 0.2. In addition, the number of optical fibers can be further reduced.

  The GaN-based semiconductor lasers LD1 to LD7 all have the same oscillation wavelength (for example, 405 nm), and the maximum output is also all the same (for example, 100 mW for the multimode laser and 30 mW for the single mode laser). As the GaN-based semiconductor lasers LD1 to LD7, lasers having an oscillation wavelength other than the above 405 nm in a wavelength range of 350 nm to 450 nm may be used.

  As shown in FIGS. 30 and 31, the combined laser light source is housed in a box-shaped package 40 having an upper opening together with other optical elements. The package 40 includes a package lid 41 created so as to close the opening thereof. After the deaeration process, a sealing gas is introduced, and the package 40 and the package lid 41 are closed by closing the opening of the package 40 with the package lid 41. 41. The combined laser light source is hermetically sealed in a closed space (sealed space) formed by 41.

  A base plate 42 is fixed to the bottom surface of the package 40, and the heat block 10, a condensing lens holder 45 that holds the condensing lens 20, and the multimode optical fiber 30 are disposed on the top surface of the base plate 42. A fiber holder 46 that holds the incident end is attached. The exit end of the multimode optical fiber 30 is drawn out of the package from an opening formed in the wall surface of the package 40.

  Further, a collimator lens holder 44 is attached to the side surface of the heat block 10, and the collimator lenses 11 to 17 are held. An opening is formed in the lateral wall surface of the package 40, and wiring 47 for supplying a driving current to the GaN-based semiconductor lasers LD1 to LD7 is drawn out of the package through the opening.

  In FIG. 31, in order to avoid complication of the figure, only the GaN-based semiconductor laser LD7 among the plurality of GaN-based semiconductor lasers is numbered, and only the collimator lens 17 among the plurality of collimator lenses is numbered. is doing.

  FIG. 32 shows the front shape of the attachment part of the collimator lenses 11-17. Each of the collimator lenses 11 to 17 is formed in a shape obtained by cutting a region including the optical axis of a circular lens having an aspherical surface into a long and narrow plane. This elongated collimator lens can be formed, for example, by molding resin or optical glass. The collimator lenses 11 to 17 are closely arranged in the arrangement direction of the light emitting points so that the length direction is orthogonal to the arrangement direction of the light emitting points of the GaN-based semiconductor lasers LD1 to LD7 (left and right direction in FIG. 32).

  On the other hand, each of the GaN-based semiconductor lasers LD1 to LD7 includes an active layer having a light emission width of 2 μm, and each of the laser beams B1 in a state in which the divergence angles in a direction parallel to and perpendicular to the active layer are, for example A laser emitting ~ B7 is used. These GaN-based semiconductor lasers LD1 to LD7 are arranged so that the light emitting points are arranged in a line in a direction parallel to the active layer.

Therefore, in the laser beams B1 to B7 emitted from the respective light emitting points, the direction in which the divergence angle is large coincides with the length direction and the divergence angle is small with respect to the elongated collimator lenses 11 to 17 as described above. Incident light is incident in a state where the direction coincides with the width direction (direction perpendicular to the length direction). That is, the collimator lenses 11 to 17 have a width of 1.1 mm and a length of 4.6 mm, and the horizontal and vertical beam diameters of the laser beams B1 to B7 incident thereon are 0.9 mm and 2. 6 mm. Each of the collimator lenses 11 to 17 has a focal length f ₁ = 3 mm, NA = 0.6, and a lens arrangement pitch = 1.25 mm.

The condensing lens 20 is formed by cutting a region including the optical axis of a circular lens having an aspheric surface into a long and narrow shape in parallel planes, and is long in the arrangement direction of the collimator lenses 11 to 17, that is, in a horizontal direction and short in a direction perpendicular thereto. Is formed. This condenser lens 20 has a focal length f ₂ = 23 mm and NA = 0.2. This condensing lens 20 is also formed by molding resin or optical glass, for example.

  In addition, since the light emitting means for illuminating the DMD uses a high-intensity fiber array light source in which the output ends of the optical fibers of the combined laser light source are arranged in an array, it has a high output and a deep depth of focus. A pattern forming apparatus can be realized. Furthermore, since the output of each fiber array light source is increased, the number of fiber array light sources required to obtain a desired output is reduced, and the cost of the pattern forming apparatus can be reduced.

  Further, since the cladding diameter of the output end of the optical fiber is smaller than the cladding diameter of the incident end, the diameter of the light emitting portion is further reduced, and the brightness of the fiber array light source can be increased. Thereby, a pattern forming apparatus having a deeper depth of focus can be realized. For example, even in the case of ultra-high resolution exposure with a beam diameter of 1 μm or less and a resolution of 0.1 μm or less, a deep depth of focus can be obtained, and high-speed and high-definition exposure is possible. Therefore, it is suitable for a thin film transistor (TFT) exposure process that requires high resolution.

  The light irradiating means is not limited to a fiber array light source including a plurality of the combined laser light sources, and for example, emits laser light incident from a single semiconductor laser having one light emitting point. A fiber array light source in which fiber light sources including optical fibers are arrayed can be used.

  Further, as the light irradiation means having a plurality of light emitting points, for example, as shown in FIG. 33, a laser in which a plurality of (for example, seven) chip-shaped semiconductor lasers LD1 to LD7 are arranged on the heat block 100. An array can be used. A chip-shaped multicavity laser 110 in which a plurality of (for example, five) light emitting points 110a shown in FIG. 34A is arranged in a predetermined direction is known. Since the multicavity laser 110 can arrange the light emitting points with high positional accuracy as compared with the case where the chip-shaped semiconductor lasers are arranged, it is easy to multiplex the laser beams emitted from the respective light emitting points. However, as the number of light emitting points increases, the multi-cavity laser 110 is likely to be bent at the time of laser manufacture. Therefore, the number of light emitting points 110a is preferably 5 or less.

  As the light irradiation means, the multi-cavity laser 110 or a plurality of multi-cavity lasers 110 on the heat block 100 in the same direction as the arrangement direction of the light emitting points 110a of each chip as shown in FIG. An arrayed multi-cavity laser array can be used as a laser light source.

  The combined laser light source is not limited to one that combines laser beams emitted from a plurality of chip-shaped semiconductor lasers. For example, as shown in FIG. 21, a combined laser light source including a chip-shaped multicavity laser 110 having a plurality of (for example, three) light emitting points 110a can be used. This combined laser light source is configured to include a multi-cavity laser 110, one multi-mode optical fiber 130, and a condensing lens 120. The multi-cavity laser 110 can be composed of, for example, a GaN-based laser diode having an oscillation wavelength of 405 nm.

  In the above configuration, each of the laser beams B emitted from each of the plurality of light emitting points 110 a of the multicavity laser 110 is collected by the condenser lens 120 and enters the core 130 a of the multimode optical fiber 130. The laser light incident on the core 130a propagates in the optical fiber, is combined into one, and is emitted.

  A plurality of light emitting points 110 a of the multicavity laser 110 are arranged in parallel within a width substantially equal to the core diameter of the multimode optical fiber 130, and a focal point substantially equal to the core diameter of the multimode optical fiber 130 is formed as the condenser lens 120. By using a convex lens of a distance or a rod lens that collimates the outgoing beam from the multi-cavity laser 110 only in a plane perpendicular to the active layer, the coupling efficiency of the laser beam B to the multi-mode optical fiber 130 can be increased. it can.

  As shown in FIG. 35, a multi-cavity laser 110 having a plurality of (for example, three) emission points is used, and a plurality of (for example, nine) multi-cavity lasers 110 are equidistant from each other on the heat block 111. A combined laser light source including the laser array 140 arranged in (1) can be used. The plurality of multi-cavity lasers 110 are arranged and fixed in the same direction as the arrangement direction of the light emitting points 110a of each chip.

  This combined laser light source includes a laser array 140, a plurality of lens arrays 114 arranged corresponding to each multi-cavity laser 110, and a single rod arranged between the laser array 140 and the plurality of lens arrays 114. The lens 113, one multimode optical fiber 130, and a condenser lens 120 are provided. The lens array 114 includes a plurality of microlenses corresponding to the emission points of the multicavity laser 110.

  In the above configuration, each of the laser beams B emitted from each of the plurality of light emitting points 110a of the plurality of multi-cavity lasers 110 is collected in a predetermined direction by the rod lens 113, and then each microlens of the lens array 114. It becomes parallel light. The collimated laser beam L is condensed by the condenser lens 120 and enters the core 130a of the multimode optical fiber 130. The laser light incident on the core 130a propagates in the optical fiber, is combined into one, and is emitted.

  Still another example of the combined laser light source will be described. In this combined laser light source, as shown in FIGS. 36A and 36B, a heat block 182 having an L-shaped cross section in the optical axis direction is mounted on a substantially rectangular heat block 180, and two heats are provided. A storage space is formed between the blocks. On the upper surface of the L-shaped heat block 182, a plurality of (for example, two) multi-cavity lasers 110 in which a plurality of light emitting points (for example, five) are arranged in an array form the light emitting points 110a of each chip. It is arranged and fixed at equal intervals in the same direction as the arrangement direction.

  A concave portion is formed in the substantially rectangular heat block 180, and a plurality of (for example, two) light emitting points (for example, five) are arranged in an array on the upper surface of the space side of the heat block 180. The multi-cavity laser 110 is arranged such that its emission point is located on the same vertical plane as the emission point of the laser chip arranged on the upper surface of the heat block 182.

  On the laser beam emission side of the multi-cavity laser 110, a collimator lens array 184 in which collimator lenses are arranged corresponding to the light emission points 110a of the respective chips is arranged. In the collimating lens array 184, the length direction of each collimating lens coincides with the direction in which the divergence angle of the laser beam is large (fast axis direction), and the width direction of each collimating lens is in the direction in which the divergence angle is small (slow axis direction). They are arranged to match. Thus, by collimating and integrating the collimating lenses, the space utilization efficiency of the laser light can be improved, the output of the combined laser light source can be increased, and the number of parts can be reduced and the cost can be reduced. .

  Further, on the laser beam emitting side of the collimating lens array 184, there is one multimode optical fiber 130 and a condensing lens 120 that condenses and couples the laser beam to the incident end of the multimode optical fiber 130. Is arranged.

  In the above configuration, each of the laser beams B emitted from each of the plurality of light emitting points 110a of the plurality of multi-cavity lasers 110 arranged on the laser blocks 180 and 182 is collimated by the collimating lens array 184 and condensed. The light is condensed by the lens 120 and enters the core 130 a of the multimode optical fiber 130. The laser light incident on the core 130a propagates in the optical fiber, is combined into one, and is emitted.

  As described above, the combined laser light source can achieve particularly high output by the multistage arrangement of multicavity lasers and the array of collimating lenses. By using this combined laser light source, a higher-intensity fiber array light source or bundle fiber light source can be configured, so that it is particularly suitable as a fiber light source constituting the laser light source of the pattern forming apparatus of the present invention.

  It should be noted that a laser module in which each of the combined laser light sources is housed in a casing and the emission end of the multimode optical fiber 130 is pulled out from the casing can be configured.

  In addition, the other end of the multimode optical fiber of the combined laser light source is coupled with another optical fiber having the same core diameter as the multimode optical fiber and a cladding diameter smaller than the multimode optical fiber. However, for example, a multimode optical fiber having a cladding diameter of 125 μm, 80 μm, 60 μm or the like may be used without coupling another optical fiber to the emission end.

Here, the permanent pattern forming method of the present invention will be further described.
In each exposure head 166 of the scanner 162, laser light B1, B2, B3, B4, B5, B6 emitted in a divergent light state from each of the GaN-based semiconductor lasers LD1 to LD7 constituting the combined laser light source of the fiber array light source 66. , And B7 are collimated by corresponding collimator lenses 11-17. The collimated laser beams B <b> 1 to B <b> 7 are collected by the condenser lens 20 and converge on the incident end face of the core 30 a of the multimode optical fiber 30.

  In this example, the collimator lenses 11 to 17 and the condenser lens 20 constitute a condensing optical system, and the condensing optical system and the multimode optical fiber 30 constitute a multiplexing optical system. That is, the laser beams B1 to B7 collected as described above by the condenser lens 20 enter the core 30a of the multimode optical fiber 30 and propagate through the optical fiber to be combined with one laser beam B. The light is emitted from the optical fiber 31 coupled to the output end of the multimode optical fiber 30.

  In each laser module, when the coupling efficiency of the laser beams B1 to B7 to the multimode optical fiber 30 is 0.85 and each output of the GaN-based semiconductor lasers LD1 to LD7 is 30 mW, the light arranged in an array For each of the fibers 31, a combined laser beam B with an output of 180 mW (= 30 mW × 0.85 × 7) can be obtained. Therefore, the output from the laser emitting unit 68 in which the six optical fibers 31 are arranged in an array is about 1 W (= 180 mW × 6).

  In the laser emitting portion 68 of the fiber array light source 66, light emission points with high luminance are arranged in a line along the main scanning direction as described above. A conventional fiber light source that couples laser light from a single semiconductor laser to a single optical fiber has a low output, so that a desired output cannot be obtained unless multiple rows are arranged. Since the laser light source has a high output, a desired output can be obtained even with a small number of columns, for example, one column.

For example, in a conventional fiber light source in which a semiconductor laser and an optical fiber are coupled on a one-to-one basis, a laser having an output of about 30 mW (milliwatt) is usually used as the semiconductor laser, and the core diameter is 50 μm and the cladding diameter is 125 μm. Since a multimode optical fiber having a numerical aperture (NA) of 0.2 is used, if an output of about 1 W (watt) is to be obtained, 48 multimode optical fibers (8 × 6) must be bundled. Since the area of the light emitting region is 0.62 mm ² (0.675 mm × 0.925 mm), the luminance at the laser emitting portion 68 is 1.6 × 10 ⁶ (W / m ² ) and one optical fiber is used. The luminance per hit is 3.2 × 10 ⁶ (W / m ² ).

On the other hand, when the light irradiating means is a means capable of irradiating the combined laser light, an output of about 1 W can be obtained with six multimode optical fibers, and the light emitting area of the laser emitting portion 68 can be obtained. Since the area is 0.0081 mm ² (0.325 mm × 0.025 mm), the luminance at the laser emitting portion 68 is 123 × 10 ⁶ (W / m ² ), which is about 80 times higher than the conventional luminance. Can be planned. Further, the luminance per optical fiber is 90 × 10 ⁶ (W / m ² ), and the luminance can be increased by about 28 times compared with the conventional one.

  Here, with reference to FIGS. 37A and 37B, the difference in depth of focus between the conventional exposure head and the exposure head of the present embodiment will be described. The diameter of the light emission region of the bundled fiber light source of the conventional exposure head in the sub-scanning direction is 0.675 mm, and the diameter of the light emission region of the fiber array light source of the exposure head in the sub-scanning direction is 0.025 mm. As shown in FIG. 37A, in the conventional exposure head, since the light emitting area of the light irradiating means (bundle-shaped fiber light source) 1 is large, the angle of the light beam incident on the DMD 3 is increased, and as a result, the scanning surface 5 is moved. The angle of the incident light beam increases. For this reason, the beam diameter tends to increase with respect to the light condensing direction (shift in the focus direction).

  On the other hand, as shown in FIG. 37B, in the exposure head in the pattern forming apparatus of the present invention, the diameter of the light emitting region of the fiber array light source 66 in the sub-scanning direction is small, so that it passes through the lens system 67 and enters the DMD 50. As a result, the angle of the light beam incident on the scanning surface 56 is reduced. That is, the depth of focus becomes deep. In this example, the diameter of the light emitting region in the sub-scanning direction is about 30 times that of the conventional one, and a depth of focus substantially corresponding to the diffraction limit can be obtained. Therefore, it is suitable for exposure of a minute spot. This effect on the depth of focus is more prominent and effective as the required light quantity of the exposure head is larger. In this example, the size of one pixel projected on the exposure surface is 10 μm × 10 μm. The DMD is a reflective spatial light modulator, but FIGS. 37A and 37B are developed views for explaining the optical relationship.

  Pattern information corresponding to the exposure pattern is input to a controller (not shown) connected to the DMD 50 and temporarily stored in a frame memory in the controller. This pattern information is data representing the density of each pixel constituting the image as binary values (whether or not dots are recorded).

  The stage 152 having the photosensitive layer 150 adsorbed on the surface is moved at a constant speed from the upstream side to the downstream side of the gate 160 along the guide 158 by a driving device (not shown). When the leading edge of the photosensitive layer 150 is detected by the detection sensor 164 attached to the gate 160 when the stage 152 passes under the gate 160, the pattern information stored in the frame memory is sequentially read out for a plurality of lines. A control signal is generated for each exposure head 166 based on the pattern information read by the data processing unit. Then, each of the micromirrors of the DMD 50 is controlled on and off for each exposure head 166 based on the generated control signal by the mirror drive control unit.

  When the DMD 50 is irradiated with laser light from the fiber array light source 66, the laser light reflected when the micromirror of the DMD 50 is in the on state forms an image on the exposed surface 56 of the photosensitive layer 150 by the lens systems 54 and 58. Is done. In this manner, the laser light emitted from the fiber array light source 66 is turned on / off for each pixel, and the photosensitive layer 150 is exposed in approximately the same number of pixel units (exposure area 168) as the number of pixels used in the DMD 50. Further, when the photosensitive layer 150 is moved at a constant speed together with the stage 152, the photosensitive layer 150 is sub-scanned in the direction opposite to the stage moving direction by the scanner 162, and a strip-shaped exposed area 170 is formed for each exposure head 166. Is done.

[Laminate]
The subject of the exposure is not particularly limited as long as it is a material having a photosensitive layer, and can be appropriately selected according to the purpose. It is preferable to be performed on the laminate.
The method for forming the photosensitive layer is not particularly limited and may be appropriately selected depending on the intended purpose. However, the photosensitive layer having a support and a photosensitive layer in which a photosensitive composition is laminated on the support. It is preferable to carry out by laminating the film on the surface of the substrate under at least one of heating and pressing.

〔Base material〕
The base material is not particularly limited, and can be appropriately selected from known materials having high surface smoothness to those having an uneven surface. A plate-shaped base material (substrate) is preferable, Specific examples include known printed wiring board forming substrates (for example, copper-clad laminates), glass plates (for example, soda glass plates), synthetic resin films, paper, metal plates, and the like. Among them, the printed wiring board forming substrate is preferable, and the printed wiring board forming substrate has already been formed in that it enables high-density mounting of a semiconductor or the like on a multilayer wiring board or a build-up wiring board. Is particularly preferred.
These substrates are preferably those containing no halogen compound as a flame retardant, and halogen-free copper-clad laminates are particularly preferred. Here, the term “halogen-free” refers to a material that satisfies the standard of JPCA (Japan Printed Circuit Industry Association) that “the contents of chlorine and bromine are each 0.09 wt% or less”.

[Photosensitive composition]
There is no restriction | limiting in particular as a photosensitive composition which forms the said photosensitive layer, Although it can select suitably from well-known photosensitive compositions, For example, a binder, a polymeric compound, and a photopolymerization initiator are mentioned. And a thermal cross-linking agent and a colorant substantially free of halogen atoms, and further containing other components such as extender pigments, thermal polymerization inhibitors and surfactants as necessary.

<< Binder >>
For example, the binder is preferably swellable in an alkaline aqueous solution, and more preferably soluble in an alkaline aqueous solution.
As the binder exhibiting swellability or solubility with respect to the alkaline aqueous solution, for example, those having an acidic group are preferably exemplified.

The binder is not particularly limited and may be appropriately selected depending on the intended purpose. For example, JP-A 51-131706, JP-A 52-94388, JP-A 64-62375, JP-A 2 Examples thereof include epoxy acrylate compounds having acidic groups described in JP-A-97513, JP-A-3-289656, JP-A-61-2243869, JP-A-2002-296776, and the like. Specifically, phenol novolac type epoxy acrylate, cresol novolac epoxy acrylate, bisphenol A type epoxy acrylate, etc., for example, reacting a carboxyl group-containing monomer such as (meth) acrylic acid with an epoxy resin or a polyfunctional epoxy compound And a dibasic acid anhydride such as phthalic anhydride is further added.
The molecular weight of the epoxy acrylate compound is preferably 1,000 to 200,000, and more preferably 2,000 to 100,000. When the molecular weight is less than 1,000, the tackiness of the surface of the photosensitive layer may become strong, and after curing of the photosensitive layer described later, the film quality may become brittle or the surface hardness may deteriorate. If it exceeds 1,000, developability may deteriorate.

An acrylic resin having at least one polymerizable group such as an acidic group and a double bond described in JP-A-6-295060 can also be used. Specifically, at least one polymerizable double bond in the molecule, for example, an acrylic group such as a (meth) acrylate group or (meth) acrylamide group, various polymerizations such as vinyl ester of carboxylic acid, vinyl ether, allyl ether Sex double bonds can be used. More specifically, acrylic resins containing carboxyl groups as acidic groups, glycidyl esters of unsaturated fatty acids such as glycidyl acrylate, glycidyl methacrylate, cinnamic acid, and epoxy groups such as cyclohexene oxide in the same molecule (meth) Examples thereof include compounds obtained by adding an epoxy group-containing polymerizable compound such as a compound having an acryloyl group. In addition, a compound obtained by adding an isocyanate group-containing polymerizable compound such as isocyanate ethyl (meth) acrylate to an acrylic resin containing an acidic group and a hydroxyl group, an acrylic resin containing an anhydride group, a hydroxyalkyl ( Examples thereof include compounds obtained by adding a polymerizable compound containing a hydroxyl group such as (meth) acrylate. As these commercially available products, for example, “Kaneka Resin AX; manufactured by Kaneka Chemical Co., Ltd.”, “Cyclomer (CYCLOMER) A-200; manufactured by Daicel Chemical Industries, Ltd.”, “CYCLOMER (M)” 200; manufactured by Daicel Chemical Industries, Ltd. "can be used.
Furthermore, a reaction product of hydroxyalkyl acrylate or hydroxyalkyl methacrylate described in JP-A No. 50-59315 and any of polycarboxylic acid anhydride and epihalohydrin can be used.

  Further, a compound obtained by adding an acid anhydride to an epoxy acrylate having a fluorene skeleton described in JP-A-5-70528, a polyamide (imide) resin described in JP-A-11-288087, and JP-A-2-097502 Styrene or a styrene derivative and an acid anhydride copolymer containing an amide group described in JP-A No. 2003-20310 and a polyimide precursor described in JP-A No. 11-282155 can be used. These may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  The molecular weight of the acrylic resin, epoxy acrylate having a fluorene skeleton, polyamide (imide), amide group-containing styrene / acid anhydride copolymer, or polyimide precursor is preferably 3,000 to 500,000, 5,000-100,000 are more preferable. When the molecular weight is less than 3,000, the tackiness of the surface of the photosensitive layer may become strong, and after curing of the photosensitive layer described later, the film quality may become brittle or the surface hardness may be deteriorated. If it exceeds 1,000, developability may deteriorate.

  5-80 mass% is preferable and, as for solid content in the said photosensitive composition solid content of the said binder, 10-70 mass% is more preferable. When the solid content is less than 5% by mass, the film strength of the photosensitive layer tends to be weak, and the tackiness of the surface of the photosensitive layer may be deteriorated. When it exceeds 50% by mass, the exposure sensitivity is increased. May decrease.

<< polymerizable compound >>
The polymerizable compound is not particularly limited and may be appropriately selected depending on the intended purpose. A compound is preferable, and for example, at least one selected from monomers having a (meth) acryl group is preferable.

  There is no restriction | limiting in particular as a monomer which has the said (meth) acryl group, According to the objective, it can select suitably, For example, polyethyleneglycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, phenoxyethyl (meth) ) Monofunctional acrylates and monofunctional methacrylates such as acrylates; polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, trimethylolpropane diacrylate, neopentylglycol di (Meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (Meth) acrylate, dipentaerythritol penta (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ether, tri (acryloyloxyethyl) isocyanurate, tri (acryloyloxyethyl) cyanurate, glycerin Poly (functional) alcohols such as tri (meth) acrylate, trimethylolpropane, glycerin, bisphenol, etc., which are subjected to addition reaction with ethylene oxide and propylene oxide, and converted to (meth) acrylate, Japanese Patent Publication No. 48-41708, Japanese Patent Publication No. 50- Urethane acrylates described in JP-A-6034, JP-A-51-37193, etc .; JP-A-48-64183, JP-B-49-43191, JP-B-52-30 Polyester acrylates described in each publication of such 90 No.; and epoxy resin and (meth) polyfunctional acrylates or methacrylates such as epoxy acrylates which are reaction products of acrylic acid. Among these, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and dipentaerythritol penta (meth) acrylate are particularly preferable.

  5-50 mass% is preferable and, as for solid content in the said photosensitive composition solid content of the said polymeric compound, 10-40 mass% is more preferable. If the solid content is less than 5% by mass, problems such as deterioration of developability and reduction in exposure sensitivity may occur, and if it exceeds 50% by mass, the adhesiveness of the photosensitive layer may become too strong. Yes, not preferred.

<< photopolymerization initiator >>
The photopolymerization initiator is not particularly limited as long as it has the ability to initiate polymerization of the polymerizable compound, and can be appropriately selected from known photopolymerization initiators. For example, it is visible from the ultraviolet region. It is preferable to have photosensitivity to the light of the photocatalyst, and may be an activator that generates an active radical by generating some action with a photoexcited sensitizer, and initiates cationic polymerization depending on the type of monomer. Initiator may be used.
The photopolymerization initiator preferably contains at least one component having a molecular extinction coefficient of at least about 50 within a range of about 300 to 800 nm (more preferably 330 to 500 nm).

  Examples of the photopolymerization initiator include halogenated hydrocarbon derivatives (for example, those having a triazine skeleton, those having an oxadiazole skeleton, those having an oxadiazole skeleton), phosphine oxide, hexaarylbiimidazole, Examples include oxime derivatives, organic peroxides, thio compounds, ketone compounds, aromatic onium salts, and ketoxime ethers.

  Examples of the halogenated hydrocarbon compound having a triazine skeleton include those described in Wakabayashi et al., Bull. Chem. Soc. Japan, 42, 2924 (1969), a compound described in British Patent 1388492, a compound described in JP-A-53-133428, a compound described in German Patent 3337024, F.I. C. J. Schaefer et al. Org. Chem. 29, 1527 (1964), compounds described in JP-A-62-258241, compounds described in JP-A-5-281728, compounds described in JP-A-5-34920, US Pat. No. 4,221,976 And the compounds described in the book.

  Wakabayashi et al., Bull. Chem. Soc. As a compound described in Japan, 42, 2924 (1969), for example, 2-phenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-chlorophenyl) -4,6 -Bis (trichloromethyl) -1,3,5-triazine, 2- (4-tolyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxyphenyl)- 4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (2,4-dichlorophenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2, 4,6-tris (trichloromethyl) -1,3,5-triazine, 2-methyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2-n-nonyl-4,6- Bis (trichloromethyl) 1,3,5-triazine, and 2-(alpha, alpha, beta-trichloroethyl) -4,6-bis (trichloromethyl) -1,3,5-triazine.

Examples of the compound described in the British Patent 1388492 include 2-styryl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methylstyryl) -4,6- Bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxystyryl)- 4-amino-6-trichloromethyl-1,3,5-triazine and the like can be mentioned.
Examples of the compounds described in JP-A-53-133428 include 2- (4-methoxy-naphth-1-yl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2 -(4-Ethoxy-naphth-1-yl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [4- (2-ethoxyethyl) -naphth-1-yl]- 4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4,7-dimethoxy-naphth-1-yl) -4,6-bis (trichloromethyl) -1,3,5- Examples include triazine and 2- (acenaphtho-5-yl) -4,6-bis (trichloromethyl) -1,3,5-triazine.

  Examples of the compound described in the specification of German Patent 3333724 include 2- (4-styrylphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- (4 -Methoxystyryl) phenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (1-naphthylvinylenephenyl) -4,6-bis (trichloromethyl) -1,3,5 -Triazine, 2-chlorostyrylphenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-thiophen-2-vinylenephenyl) -4,6-bis (trichloromethyl)- 1,3,5-triazine, 2- (4-thiophene-3-vinylenephenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-furan-2 Vinylenephenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, and 2- (4-benzofuran-2-vinylenephenyl) -4,6-bis (trichloromethyl) -1,3 5-triazine etc. are mentioned.

  F. above. C. J. Schaefer et al. Org. Chem. 29, 1527 (1964) include, for example, 2-methyl-4,6-bis (tribromomethyl) -1,3,5-triazine, 2,4,6-tris (tribromomethyl); -1,3,5-triazine, 2,4,6-tris (dibromomethyl) -1,3,5-triazine, 2-amino-4-methyl-6-tri (bromomethyl) -1,3,5- Examples include triazine and 2-methoxy-4-methyl-6-trichloromethyl-1,3,5-triazine.

  Examples of the compounds described in JP-A-62-258241 include 2- (4-phenylethynylphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- Naphthyl-1-ethynylphenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- (4-tolylethynyl) phenyl) -4,6-bis (trichloromethyl) -1 , 3,5-triazine, 2- (4- (4-methoxyphenyl) ethynylphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- (4-isopropylphenyl) Ethynyl) phenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- (4-ethylphenylethynyl) phenyl) -4,6-bis (trichloromethyl) Le) -1,3,5-triazine.

  Examples of the compound described in JP-A-5-281728 include 2- (4-trifluoromethylphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (2, 6-difluorophenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (2,6-dichlorophenyl) -4,6-bis (trichloromethyl) -1,3,5- Examples include triazine, 2- (2,6-dibromophenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine.

  Examples of the compound described in JP-A-5-34920 include 2,4-bis (trichloromethyl) -6- [4- (N, N-diethoxycarbonylmethylamino) -3-bromophenyl] -1, 3,5-triazine, trihalomethyl-s-triazine compounds described in US Pat. No. 4,239,850, 2,4,6-tris (trichloromethyl) -s-triazine, 2- (4-chlorophenyl) Examples include -4,6-bis (tribromomethyl) -s-triazine.

  Examples of the compound described in US Pat. No. 4,221,976 include compounds having an oxadiazole skeleton (for example, 2-trichloromethyl-5-phenyl-1,3,4-oxadiazole, 2- Trichloromethyl-5- (4-chlorophenyl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (1-naphthyl) -1,3,4-oxadiazole, 2-trichloromethyl-5 -(2-naphthyl) -1,3,4-oxadiazole, 2-tribromomethyl-5-phenyl-1,3,4-oxadiazole, 2-tribromomethyl-5- (2-naphthyl) -1,3,4-oxadiazole; 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, 2-trichloromethyl-5- (4-chlorostyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (4-methoxystyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (1-naphthyl) -1, 3,4-oxadiazole, 2-trichloromethyl-5- (4-n-butoxystyryl) -1,3,4-oxadiazole, 2-tribromomethyl-5-styryl-1,3,4 Oxadiazole and the like).

  Examples of the oxime derivative suitably used in the present invention include 3-benzoyloxyiminobutan-2-one, 3-acetoxyiminobutan-2-one, 3-propionyloxyiminobutan-2-one, and 2-acetoxy. Iminopentan-3-one, 2-acetoxyimino-1-phenylpropan-1-one, 2-benzoyloxyimino-1-phenylpropan-1-one, 3- (4-toluenesulfonyloxy) iminobutane-2- ON, and 2-ethoxycarbonyloxyimino-1-phenylpropan-1-one.

  Further, as photopolymerization initiators other than the above, acridine derivatives (for example, 9-phenylacridine, 1,7-bis (9,9′-acridinyl) heptane, etc.), N-phenylglycine, and the like, polyhalogen compounds (for example, Carbon tetrabromide, phenyltribromomethylsulfone, phenyltrichloromethylketone, etc.), coumarins (for example, 3- (2-benzofuroyl) -7-diethylaminocoumarin, 3- (2-benzofuroyl) -7- (1-pyrrolidinyl) ) Coumarin, 3-benzoyl-7-diethylaminocoumarin, 3- (2-methoxybenzoyl) -7-diethylaminocoumarin, 3- (4-dimethylaminobenzoyl) -7-diethylaminocoumarin, 3,3′-carbonylbis (5 , 7-di-n-propoxycoumarin), 3,3′-carbonylbis (7-diethylaminocoumarin), 3-benzoyl-7-methoxycoumarin, 3- (2-furoyl) -7-diethylaminocoumarin, 3- (4-diethylaminocinnamoyl) -7-diethylaminocoumarin, 7-methoxy-3- (3-pyridylcarbonyl) coumarin, 3-benzoyl-5,7-dipropoxycoumarin, 7-benzotriazol-2-ylcoumarin, JP-A-5-19475, JP-A-7-271028, JP-A-2002-363206 No., JP-A-2002-363207, JP-A-2002-363208, JP-A-2002-363209, etc.), amines (for example, ethyl 4-dimethylaminobenzoate, 4-dimethylaminobenzoate) N-butyl acid, 4-dimethylaminobenzoic acid phenethyl, 4-dimethyl 2-phthalimidoethyl tilaminobenzoate, 2-methacryloyloxyethyl 4-dimethylaminobenzoate, pentamethylenebis (4-dimethylaminobenzoate), phenethyl of 3-dimethylaminobenzoic acid, pentamethylene ester, 4-dimethylaminobenzaldehyde, 2-chloro-4-dimethylaminobenzaldehyde, 4-dimethylaminobenzyl alcohol, ethyl (4-dimethylaminobenzoyl) acetate, 4-piperidinoacetophenone, 4-dimethylaminobenzoin, N, N-dimethyl-4-toluidine, N, N-diethyl-3-phenetidine, tribenzylamine, dibenzylphenylamine, N-methyl-N-phenylbenzylamine, 4-bromo-N, N-dimethylaniline, tridodecylamine, amino Nofluoranes (ODB, ODBII, etc.), crystal violet lactone, leuco crystal violet, etc., acylphosphine oxides (for example, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) ) -2,4,4-trimethyl-pentylphenylphosphine oxide, Lucirin TPO, etc.), metallocenes (for example, bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3-) (1H-pyrrol-1-yl) -phenyl) titanium, η5-cyclopentadienyl-η6-cumenyl-iron (1 +)-hexafluorophosphate (1-), etc.), JP-A-53-133428, Kosho 57-1819, 57-609 JP, and include compounds described in U.S. Patent No. 3,615,455.

  Examples of the ketone compound include benzophenone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 4-methoxybenzophenone, 2-chlorobenzophenone, 4-chlorobenzophenone, 4-bromobenzophenone, 2-carboxybenzophenone, 2-ethoxycarbonylbenzolphenone, benzophenonetetracarboxylic acid or tetramethyl ester thereof, 4,4′-bis (dialkylamino) benzophenone (for example, 4,4′-bis (dimethylamino) benzophenone, 4,4′- Bisdicyclohexylamino) benzophenone, 4,4′-bis (diethylamino) benzophenone, 4,4′-bis (dihydroxyethylamino) benzophenone, 4-methoxy-4′-dimethylamino Nzophenone, 4,4'-dimethoxybenzophenone, 4-dimethylaminobenzophenone, 4-dimethylaminoacetophenone, benzyl, anthraquinone, 2-t-butylanthraquinone, 2-methylanthraquinone, phenanthraquinone, xanthone, thioxanthone, 2-chloro -Thioxanthone, 2,4-diethylthioxanthone, fluorenone, 2-benzyl-dimethylamino-1- (4-morpholinophenyl) -1-butanone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino -1-propanone, 2-hydroxy-2-methyl- [4- (1-methylvinyl) phenyl] propanol oligomer, benzoin, benzoin ethers (for example, benzoin methyl ether, benzoin ethyl ether, In propyl ether, benzoin isopropyl ether, benzoin phenyl ether, benzyl dimethyl ketal), acridone, chloro acridone, N- methyl acridone, N- butyl acridone, N- butyl - such as chloro acrylic pyrrolidone.

In addition to the photopolymerization initiator, a sensitizer can be added for the purpose of adjusting the exposure sensitivity and the photosensitive wavelength in exposure to the photosensitive layer described later.
The sensitizer can be appropriately selected by visible light, ultraviolet light, visible light laser, or the like as a light irradiation means described later.
The sensitizer is excited by active energy rays and interacts with other substances (for example, radical generator, acid generator, etc.) (for example, energy transfer, electron transfer, etc.), thereby generating radicals, acids, etc. It is possible to generate a useful group of

  The sensitizer is not particularly limited and may be appropriately selected from known sensitizers. For example, known polynuclear aromatics (for example, pyrene, perylene, triphenylene), xanthenes (for example, , Fluorescein, eosin, erythrosine, rhodamine B, rose bengal), cyanines (eg, indocarbocyanine, thiacarbocyanine, oxacarbocyanine), merocyanines (eg, merocyanine, carbomerocyanine), thiazines (eg, thionine, Methylene blue, toluidine blue), acridines (eg, acridine orange, chloroflavin, acriflavine), anthraquinones (eg, anthraquinone), squariums (eg, squalium), acridones (eg, acridone, chloroacrine) Don, N-methylacridone, N-butylacridone, N-butyl-chloroacridone, etc.), coumarins (for example, 3- (2-benzofuroyl) -7-diethylaminocoumarin, 3- (2-benzofuroyl)- 7- (1-pyrrolidinyl) coumarin, 3-benzoyl-7-diethylaminocoumarin, 3- (2-methoxybenzoyl) -7-diethylaminocoumarin, 3- (4-dimethylaminobenzoyl) -7-diethylaminocoumarin, 3,3 '-Carbonylbis (5,7-di-n-propoxycoumarin), 3,3'-carbonylbis (7-diethylaminocoumarin), 3-benzoyl-7-methoxycoumarin, 3- (2-furoyl) -7- Diethylaminocoumarin, 3- (4-diethylaminocinnamoyl) -7-diethylaminocoumarin Examples thereof include 7-methoxy-3- (3-pyridylcarbonyl) coumarin, 3-benzoyl-5,7-dipropoxycoumarin, and others, and JP-A-5-19475, JP-A-7-271028, JP-A-2002-. No. 363206, JP-A No. 2002-363207, JP-A No. 2002-363208, JP-A No. 2002-363209, and the like.

  Examples of the combination of the photopolymerization initiator and the sensitizer include, for example, an electron transfer start system described in JP-A-2001-305734 [(1) an electron donating initiator and a sensitizing dye, (2) A combination of an electron-accepting initiator and a sensitizing dye, (3) an electron-donating initiator, a sensitizing dye and an electron-accepting initiator (ternary initiation system), and the like.

  As content of the said sensitizer, 0.05-30 mass% is preferable with respect to all the components in the said photosensitive composition, 0.1-20 mass% is more preferable, 0.2-10 mass% Is particularly preferred. When the content is less than 0.05% by mass, the sensitivity to active energy rays is reduced, the exposure process takes time, and productivity may be reduced. The sensitizer may be precipitated from the photosensitive layer.

The said photoinitiator may be used individually by 1 type, and may use 2 or more types together.
Particularly preferred examples of the photopolymerization initiator include halogenated carbonization having the phosphine oxides, the α-aminoalkyl ketones, and the triazine skeleton capable of supporting laser light having a wavelength of 405 nm in the exposure described later. Examples include a composite photoinitiator, a hexaarylbiimidazole compound, or titanocene, which is a combination of a hydrogen compound and an amine compound as a sensitizer described later.

  As content in the said photosensitive composition of the said photoinitiator, 0.1-30 mass% is preferable, 0.5-20 mass% is more preferable, 0.5-15 mass% is especially preferable.

<< Thermal crosslinking agent >>
The thermal crosslinking agent is not particularly limited and may be appropriately selected depending on the purpose. In order to improve the film strength after curing of the photosensitive layer formed using the photosensitive composition, developability For example, an epoxy resin compound having at least two oxirane groups in one molecule and an oxetane compound having at least two oxetanyl groups in one molecule can be used within a range that does not adversely affect the like.
Examples of the epoxy resin compound include a bixylenol type or biphenol type epoxy resin (“YX4000; manufactured by Japan Epoxy Resin Co., Ltd.”) or a mixture thereof, a heterocyclic epoxy resin having an isocyanurate skeleton (“TEPIC; Nissan”). Chemical Industries, "Araldite PT810; Ciba Specialty Chemicals, etc.), bisphenol A type epoxy resin, novolac type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, glycidylamine type epoxy Resin, hydantoin type epoxy resin, alicyclic epoxy resin, trihydroxyphenylmethane type epoxy resin, bisphenol S type epoxy resin, bisphenol A novolac type epoxy resin, tetraphenylolethane type Poxy resin, glycidyl phthalate resin, tetraglycidyl xylenoylethane resin, naphthalene group-containing epoxy resin (“ESN-190, ESN-360; manufactured by Nippon Steel Chemical Co., Ltd.”, “HP-4032, EXA-4750, EXA-4700; large Nippon Ink Chemical Co., Ltd. ”), epoxy resins having a dicyclopentadiene skeleton (“ HP-7200, HP-7200H; manufactured by Dainippon Ink & Chemicals ”etc.), glycidyl methacrylate copolymer epoxy resin (“ CP -50S, CP-50M; manufactured by NOF Corporation, etc.), a copolymer epoxy resin of cyclohexylmaleimide and glycidyl methacrylate, and the like, but is not limited thereto. These epoxy resins may be used individually by 1 type, and may use 2 or more types together.

  Examples of the oxetane compound include bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl] ether, 1,4-bis [(3-methyl -3-Oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) In addition to polyfunctional oxetanes such as methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate or oligomers or copolymers thereof, oxetane groups and novolak resins , Poly (p-hydroxystyrene), cardo-type bisphe And ether compounds with hydroxyl groups, such as siloles, calixarenes, calixresorcinarenes, silsesquioxanes, and the like, as well as unsaturated monomers having an oxetane ring and alkyl (meth) acrylates. And a copolymer thereof.

  1-50 mass% is preferable and, as for solid content in the said photosensitive composition solid content of the said epoxy resin compound or oxetane compound, 3-30 mass% is more preferable. When the solid content is less than 1% by mass, the hygroscopicity of the cured film is increased, resulting in deterioration of insulation, or solder heat resistance, electroless plating resistance, and the like may be reduced. If it exceeds 50% by mass, the developability may deteriorate and the exposure sensitivity may decrease, which is not preferable.

Moreover, in order to accelerate the thermosetting of the epoxy resin compound or the oxetane compound, for example, dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethyl Amine compounds such as benzylamine and 4-methyl-N, N-dimethylbenzylamine; quaternary ammonium salt compounds such as triethylbenzylammonium chloride; blocked isocyanate compounds such as dimethylamine; imidazole, 2-methylimidazole and 2-ethylimidazole , 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole, etc. Bicyclic amidine compounds and salts thereof; phosphorus compounds such as triphenylphosphine; guanamine compounds such as melamine, guanamine, acetoguanamine, benzoguanamine; 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2 -Vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino-S-triazine isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine isocyanuric acid S-triazine derivatives such as adducts can be used. These may be used alone or in combination of two or more. The epoxy resin compound or the oxetane compound is a curing catalyst, or any compound that can accelerate the reaction between the epoxy resin compound and the oxetane compound and a carboxyl group. May be.
Solid content in the said photosensitive composition solid content of the said epoxy resin, the said oxetane compound, and the compound which can accelerate | stimulate thermosetting with these and carboxylic acid is 0.01-15 mass% normally.

  Further, as the thermal crosslinking agent, a polyisocyanate compound described in JP-A-5-9407 can be used, and the polyisocyanate compound is aliphatic, cycloaliphatic or aromatic containing at least two isocyanate groups. It may be derived from a group-substituted aliphatic compound. Specifically, a mixture of 1,3-phenylene diisocyanate and 1,4-phenylene diisocyanate, 2,4- and 2,6-toluene diisocyanate, 1,3- and 1,4-xylylene diisocyanate, bis (4 -Isocyanate-phenyl) methane, bis (4-isocyanatocyclohexyl) methane, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, etc .; bifunctional isocyanates, trimethylolpropane, pentalysitol, glycerin, etc. An alkylene oxide adduct of the polyfunctional alcohol and an adduct of the bifunctional isocyanate; hexamethylene diisocyanate, hexamethylene-1,6-diisocyanate Cyclic trimers, such as preparative and derivatives thereof; and the like.

Furthermore, for the purpose of improving the preservability of the photosensitive composition of the present invention or the photosensitive film of the present invention, a compound obtained by reacting a blocking agent with the isocyanate group of the polyisocyanate and its derivative is used. May be.
Examples of the isocyanate group blocking agent include isopropanol, tert. Alcohols such as butanol; lactams such as ε-caprolactam; phenol, cresol, p-tert. -Butylphenol, p-sec. -Butylphenol, p-sec. -Phenols such as amylphenol, p-octylphenol, p-nonylphenol; heterocyclic hydroxyl compounds such as 3-hydroxypyridine and 8-hydroxyquinoline; dialkylmalonate, methylethylketoxime, acetylacetone, alkylacetoacetate oxime, acetoxime, Active methylene compounds such as cyclohexanone oxime; and the like. In addition to these, compounds having at least one polymerizable double bond and at least one blocked isocyanate group in the molecule described in JP-A-6-295060 can be used.

  Moreover, an aldehyde condensation product, a resin precursor, etc. can be used. Specifically, N, N′-dimethylolurea, N, N′-dimethylolmalonamide, N, N′-dimethylolsuccinimide, trimethylolmelamine, tetramethylolmelamine, hexamethylolmelamine, 1,3-N, N'-dimethylol terephthalamide, 2,4,6-trimethylolphenol, 2,6-dimethylol-4-methyliloanisole, 1,3-dimethylol-4,6-diisopropylbenzene and the like can be mentioned. In place of these methylol compounds, the corresponding ethyl or butyl ether, or acetic acid or propionic acid ester may be used. Further, hexamethoxymethylol melamine composed of a formaldehyde condensation product of melamine and urea, butyl ether of a melamine and formaldehyde condensation product, or the like may be used.

  1-40 mass% is preferable and, as for solid content in the said photosensitive composition solid content of the said thermal crosslinking agent, 3-20 mass% is more preferable. When the solid content is less than 1% by mass, improvement in the film strength of the cured film is not recognized, and when it exceeds 40% by mass, the developability and the exposure sensitivity may be lowered.

<< Colorant >>
The colorant is not particularly limited as long as it does not substantially contain a halogen atom, and can be appropriately selected according to the purpose. The colorant substantially free of halogen atoms means a colorant free of halogen atoms in the structural formula.
As the colorant, for example, a blue pigment containing no halogen atom may be used alone, and for the purpose of obtaining the same green color tone as when phthalocyanine green is used, a blue pigment containing no halogen atom And a yellow pigment containing no halogen atom may be used in combination, or a yellow pigment containing no halogen atom and a black pigment containing no halogen atom may be used in combination.

Examples of the blue pigment containing no halogen atom include a color index (CI), C.I. I. Examples include those classified as pigment blue. I. Copper phthalocyanine blue represented by CI Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4, and 15: 6; I. A metal-free phthalocyanine blue represented by CI Pigment Blue 16; I. Cobalt phthalocyanine represented by CI Pigment Blue 75, C.I. I. Alkaline blue represented by pigment blue 2, 3, 10, 14, 18, 19, 24, 56, 57, and 61; I. Victoria Blue, C.I. I. Sulfonated CuPc, C.I. I. Bitumen indicated by pigment blue 27, C.I. I. Ultramarine blue represented by pigment blue 29, C.I. I. Cobalt blue represented by pigment blue 28, C.I. I. Sky blue indicated by pigment blue 35, C.I. I. Co (Al, Cr) ₂ O ₄ , C.I. I. Disazo represented by pigment blue 25 and 26, C.I. I. Indanthrone represented by Pigment Blue 60, and C.I. I. Examples thereof include indigo indicated by pigment blue 63 and 66.

  In addition, the blue pigment containing no halogen atom has a structure similar to that of chlorine-based phthalocyanine green from the viewpoint of replacing chlorine-based phthalocyanine green that has been widely used in the past, and has the same cost and coating properties as conventional products. A phthalocyanine pigment capable of realizing (chemical resistance, heat resistance, electrical insulation, adhesion, hardness, etc.) is preferable. Examples of the phthalocyanine pigment include the copper phthalocyanine blue, the metal-free phthalocyanine blue, the cobalt phthalocyanine, titanyl phthalocyanine blue, iron phthalocyanine blue, nickel phthalocyanine blue, aluminum phthalocyanine blue, and tin phthalocyanine blue. The copper phthalocyanine blue is particularly preferable.

  Examples of the yellow pigment containing no halogen atom include a color index (C.I.), C.I. I. Examples include those classified as pigment yellow. I. Quinophthalone represented by CI Pigment Yellow 138, C.I. I. Monoazo yellow represented by CI Pigment Yellow 1, 4, 5, 7, 9, 65, 74, 150, 154, and 167; I. Benzimidazolone yellow represented by CI Pigment Yellow 120, 151, 175, 180, 181, and 194; I. Flavantron Yellow indicated by Pigment Yellow 24, C.I. I. Azomethyl yellow represented by pigment yellow 117 and 129, C.I. I. Anthraquinone yellow represented by C.I. Pigment Yellow 24, 108, 123, 147, and 193; I. Isoindoline yellow represented by pigment yellow 139 and 185, C.I. I. Disazo yellow represented by pigment yellow 155, C.I. I. A condensed polycyclic system represented by C.I. Pigment Yellow 148, 182 and 192; I. Iron oxide represented by pigment yellow 42, C.I. I. Disazomethine represented by CI Pigment Yellow 101, C.I. I. Pigment Yellow 61, 62, 100, 104, 133, 168, and 169, and C.I. I. And metal complexes represented by CI Pigment Yellow 150, 153, 177, and 179.

  Examples of the black pigment containing no halogen atom include a color index (CI), C.I. I. Examples include those classified as pigment black. I. Carbon black represented by pigment black 6, 7, 9, and 18; I. Graphite pigments represented by pigment black 8 and 10, C.I. I. Perylene represented by pigment black 31 and 32, C.I. I. Iron oxide pigments represented by C.I. Pigment Black 11, 12, and 27; I. Cobalt oxide pigments represented by C.I. Pigment Black 13, 25, and 29; I. A copper oxide pigment represented by pigment black 15 or 28, C.I. I. Manganese pigments represented by CI pigment black 14 and 26, C.I. I. Antimony oxide pigments represented by C.I. Pigment Black 23, C.I. I. A nickel oxide pigment represented by CI Pigment Black 30, and C.I. I. Examples thereof include a pigment represented by pigment black 34. In addition, molybdenum sulfide, bismuth sulfide, and the like are also included.

  The solid content in the photosensitive composition solid content of the colorant can be determined in consideration of the exposure sensitivity, resolution, etc. of the photosensitive layer during permanent pattern formation, depending on the type of the colorant. Generally, 0.05 to 10% by mass is preferable, and 0.1 to 5% by mass is more preferable.

<< Other ingredients >>
Examples of the other components include thermal polymerization inhibitors, plasticizers, extender pigments, and the like, and further adhesion promoters to the substrate surface and other auxiliaries (for example, conductive particles, fillers, An antifoaming agent, a flame retardant, a leveling agent, a peeling accelerator, an antioxidant, a fragrance, a surface tension adjusting agent, a chain transfer agent, etc.) may be used in combination. By appropriately containing these components, it is possible to adjust properties such as stability, photographic properties, film physical properties and the like of the intended photosensitive composition or the photosensitive film described later.

-Thermal polymerization inhibitor-
The thermal polymerization inhibitor may be added to prevent thermal polymerization or temporal polymerization of the polymerizable compound.
Examples of the thermal polymerization inhibitor include 4-methoxyphenol, hydroquinone, alkyl or aryl-substituted hydroquinone, t-butylcatechol, pyrogallol, 2-hydroxybenzophenone, 4-methoxy-2-hydroxybenzophenone, cuprous chloride, phenothiazine. , Chloranil, naphthylamine, β-naphthol, 2,6-di-tert-butyl-4-cresol, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), pyridine, nitrobenzene, dinitrobenzene, picric acid 4-toluidine, methylene blue, copper and organic chelating agent reactant, methyl salicylate, phenothiazine, nitroso compound, chelate of nitroso compound and Al, and the like.

  As content of the said thermal-polymerization inhibitor, 0.001-5 mass% is preferable with respect to the said polymeric compound, 0.005-2 mass% is more preferable, 0.01-1 mass% is especially preferable. When the content is less than 0.001% by mass, stability during storage may be lowered, and when it exceeds 5% by mass, sensitivity to active energy rays may be lowered.

-Extender pigment-
If necessary, the photosensitive composition may be inorganic for the purpose of improving the surface hardness of the permanent pattern or keeping the linear expansion coefficient low, or keeping the dielectric constant or dielectric loss tangent of the cured film itself low. Pigments and organic fine particles can be added.
The inorganic pigment is not particularly limited and may be appropriately selected from known ones. For example, kaolin, barium sulfate, barium titanate, silicon oxide powder, finely divided silicon oxide, gas phase method silica, amorphous Examples thereof include silica, crystalline silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, and mica.
The average particle diameter of the inorganic pigment is preferably less than 10 μm, and more preferably 3 μm or less. When the average particle size is 10 μm or more, resolution may be deteriorated due to light scattering.
There is no restriction | limiting in particular as said organic fine particle, According to the objective, it can select suitably, For example, a melamine resin, a benzoguanamine resin, a crosslinked polystyrene resin etc. are mentioned. Further, silica having an average particle diameter of 1 to 5 μm and an oil absorption of about 100 to 200 ml / g, spherical porous fine particles made of a crosslinked resin, and the like can be used.

  The amount of the extender is preferably 5 to 60% by mass. When the addition amount is less than 5% by mass, the linear expansion coefficient may not be sufficiently reduced. When the addition amount exceeds 60% by mass, when the cured film is formed on the photosensitive layer surface, The film quality becomes fragile, and when a wiring is formed using a permanent pattern, the function of the wiring as a protective film may be impaired.

-Adhesion promoter-
In order to improve the adhesion between the layers or the adhesion between the photosensitive layer and the substrate, a known so-called adhesion promoter can be used for each layer.

  Preferred examples of the adhesion promoter include adhesion promoters described in JP-A-5-11439, JP-A-5-341532, JP-A-6-43638, and the like. Specifically, benzimidazole, benzoxazole, benzthiazole, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzthiazole, 3-morpholinomethyl-1-phenyl-triazole-2-thione, 3-morpholino Methyl-5-phenyl-oxadiazole-2-thione, 5-amino-3-morpholinomethyl-thiadiazole-2-thione, and 2-mercapto-5-methylthio-thiadiazole, triazole, tetrazole, benzotriazole, carboxybenzotriazole Amino group-containing benzotriazole, silane coupling agents, and the like.

  As content of the said adhesion promoter, 0.001 mass%-20 mass% are preferable with respect to all the components in the said photosensitive composition, 0.01-10 mass% is more preferable, 0.1 mass% ˜5% by weight is particularly preferred.

-Method for forming photosensitive layer-
As the method for forming the photosensitive layer in the laminate, (1) a method of applying the photosensitive composition to the surface of the substrate and drying, and (2) the photosensitive composition on a support. A method of laminating a photosensitive film, which has been coated and dried to form a photosensitive layer, on the surface of the substrate under at least one of heating and pressurization, is excellent in handleability and requires precise lamination. Therefore, the method (2) is preferable.

  The coating and drying method is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the photosensitive composition is dissolved, emulsified or dispersed on the surface of the base material in water or a solvent. And a method of laminating by preparing a photosensitive composition solution, applying the solution directly, and drying the solution.

  There is no restriction | limiting in particular as a solvent of the said photosensitive composition solution, According to the objective, it can select suitably, For example, methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, n-hexanol Alcohols such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diisobutyl ketone, etc .; ethyl acetate, butyl acetate, n-amyl acetate, methyl sulfate, ethyl propionate, dimethyl phthalate, ethyl benzoate, and Esters such as methoxypropyl acetate; aromatic hydrocarbons such as toluene, xylene, benzene, ethylbenzene; carbon tetrachloride, trichloroethylene, chloroform, 1,1,1-trichloroethane, methylene chloride, monochlorobenzene Halogenated hydrocarbons of: ethers such as tetrahydrofuran, diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 1-methoxy-2-propanol; dimethylformamide, dimethylacetamide, dimethylsulfoxide, sulfolane, etc. . These may be used alone or in combination of two or more. Moreover, you may add a well-known surfactant.

The coating method is not particularly limited and can be appropriately selected depending on the purpose. For example, using a spin coater, a slit spin coater, a roll coater, a die coater, a curtain coater, etc. The method of apply | coating is mentioned.
The drying conditions vary depending on each component, the type of solvent, the use ratio, and the like, but are usually about 60 to 110 ° C. for about 30 seconds to 15 minutes.

  There is no restriction | limiting in particular as thickness of the said photosensitive layer, Although it can select suitably according to the objective, For example, 3-100 micrometers is preferable and 5-70 micrometers is more preferable.

The halogen content of the photosensitive layer is preferably less than 900 ppm, and more preferably less than 300 ppm.
As a method for quantifying the halogen content of the photosensitive layer, for example, the photosensitive layer is burned in a combustion flask, and the halogen content in the absorbing solution in which the generated gas is absorbed is analyzed by ion chromatography or the like. Can be quantified.

[Photosensitive film]
The photosensitive film has at least a support and a photosensitive layer, preferably a protective film, and, if necessary, other layers such as a cushion layer and an oxygen barrier layer (PC layer). Having a layer.
The form of the photosensitive film is not particularly limited and may be appropriately selected depending on the purpose. For example, the photosensitive layer and the protective film are provided in this order on the support, On the support, the PC layer, the photosensitive layer, and the protective film are arranged in this order. On the support, the cushion layer, the PC layer, the photosensitive layer, and the protective film are arranged in this order. The form which has is mentioned. The photosensitive layer may be a single layer or a plurality of layers.

The photosensitive layer in the photosensitive film is formed of the photosensitive composition.
There is no restriction | limiting in particular as a location provided in the said photosensitive film of the said photosensitive layer, Although it can select suitably according to the objective, Usually, it laminates | stacks on the said support body.
In addition, when the said photosensitive film has a protective film mentioned later, it is preferable to peel this protective film and to laminate | stack so that the said photosensitive layer may overlap with the said base material.

<< Support >>
The support is not particularly limited and may be appropriately selected depending on the intended purpose. However, it is preferable that the photosensitive layer can be peeled off and the light transmittance is good, and further the surface smoothness Is more preferable.

The support is preferably made of a synthetic resin and transparent, for example, polyethylene terephthalate, polyethylene naphthalate, polypropylene, polyethylene, cellulose triacetate, cellulose diacetate, poly (meth) acrylic acid alkyl ester, poly ( (Meth) acrylic acid ester copolymer, polyvinyl chloride, polyvinyl alcohol, polycarbonate, polystyrene, cellophane, polyvinylidene chloride copolymer, polyamide, polyimide, vinyl chloride / vinyl acetate copolymer, polytetrafluoroethylene, polytrifluoro Various plastic films, such as ethylene, a cellulose film, and a nylon film, are mentioned, Among these, polyethylene terephthalate is particularly preferable. These may be used alone or in combination of two or more.
As the support, for example, the support described in JP-A-4-208940, JP-A-5-80503, JP-A-5-173320, JP-A-5-72724, or the like is used. You can also.

  There is no restriction | limiting in particular as thickness of the said support body, Although it can select suitably according to the objective, For example, 4-300 micrometers is preferable and 5-175 micrometers is more preferable.

  There is no restriction | limiting in particular as a shape of the said support body, Although it can select suitably according to the objective, A long shape is preferable. There is no restriction | limiting in particular as the length of the said elongate support body, For example, the thing of length 10m-20000m is mentioned.

<< Protective film >>
The protective film has a function of preventing and protecting the photosensitive layer from being stained and damaged.
There is no restriction | limiting in particular as a location provided in the said photosensitive film of the said protective film, Although it can select suitably according to the objective, Usually, it is provided on the said photosensitive layer.
Examples of the protective film include those used for the support, silicone paper, polyethylene, paper laminated with polypropylene, polyolefin or polytetrafluoroethylene sheet, and among these, polyethylene film, Polypropylene film is preferred.
There is no restriction | limiting in particular as thickness of the said protective film, Although it can select suitably according to the objective, For example, 5-100 micrometers is preferable and 8-30 micrometers is more preferable.
When the protective film is used, it is preferable that the adhesive force A between the photosensitive layer and the support and the adhesive force B between the photosensitive layer and the protective film satisfy the relationship of adhesive force A> adhesive force B.
Examples of the combination of the support and the protective film (support / protective film) include polyethylene terephthalate / polypropylene, polyethylene terephthalate / polyethylene, polyvinyl chloride / cellophane, polyimide / polypropylene, polyethylene terephthalate / polyethylene terephthalate, and the like. . Moreover, the relationship of the above adhesive forces can be satisfy | filled by surface-treating at least any one of a support body and a protective film. The surface treatment of the support may be performed in order to increase the adhesive force with the photosensitive layer. For example, coating of a primer layer, corona discharge treatment, flame treatment, ultraviolet irradiation treatment, high frequency irradiation treatment, glow treatment Examples thereof include discharge irradiation treatment, active plasma irradiation treatment, and laser beam irradiation treatment.

Moreover, as a static friction coefficient of the said support body and the said protective film, 0.3-1.4 are preferable and 0.5-1.2 are more preferable.
When the coefficient of static friction is less than 0.3, slipping is excessive, so that winding deviation may occur when the roll is formed, and when it exceeds 1.4, it is difficult to wind into a good roll. Sometimes.

  The photosensitive film is preferably stored, for example, wound around a cylindrical core, wound in a long roll shape. There is no restriction | limiting in particular as the length of the said elongate photosensitive film, For example, it can select suitably from the range of 10m-20,000m. Further, slitting may be performed so that the user can easily use, and a long body in the range of 100 m to 1,000 m may be formed into a roll. In this case, it is preferable that the support is wound up so as to be the outermost side. Moreover, you may slit the said roll-shaped photosensitive film in a sheet form. When storing, from the viewpoint of protecting the end face and preventing edge fusion, it is preferable to install a separator (particularly moisture-proof and containing a desiccant) on the end face, and use a low moisture-permeable material for packaging. Is preferred.

The protective film may be surface-treated in order to adjust the adhesion between the protective film and the photosensitive layer. In the surface treatment, for example, an undercoat layer made of a polymer such as polyorganosiloxane, fluorinated polyolefin, polyfluoroethylene, or polyvinyl alcohol is formed on the surface of the protective film. The undercoat layer can be formed by applying the polymer coating solution to the surface of the protective film and then drying at 30 to 150 ° C. (especially 50 to 120 ° C.) for 1 to 30 minutes.
In addition to the photosensitive layer, the support, and the protective film, a cushion layer, an oxygen blocking layer (PC layer), a release layer, an adhesive layer, a light absorption layer, a surface protective layer, and the like may be included. .
The cushion layer is a layer that has no tackiness at room temperature and melts and flows when laminated under vacuum and heating conditions.
The PC layer is usually a coating of about 0.5 to 5 μm formed mainly of polyvinyl alcohol.

There is no restriction | limiting in particular as said heating temperature at the time of laminating | stacking the said photosensitive film on the said base material, Although it can select suitably according to the objective, For example, 70-130 degreeC is preferable and 80-110 degreeC is preferable. Is more preferable.
There is no restriction | limiting in particular as the pressure of the said pressurization at the time of laminating | stacking the said photosensitive film on the said base material, Although it can select suitably according to the objective, For example, 0.01-1.0 MPa is preferable. 0.05 to 1.0 MPa is more preferable.

  There is no restriction | limiting in particular as an apparatus which performs at least any one of the said heating and pressurization, According to the objective, it can select suitably, For example, heat press, a heat roll laminator (For example, Taisei Laminator company make, VP-II) ), A vacuum laminator (for example, MVLP500, manufactured by Meiki Seisakusho) and the like are preferable.

The photosensitive film can be widely used for forming a permanent pattern such as a printed wiring board, a color filter, a pillar material, a rib material, a spacer, a display member such as a partition, a hologram, a micromachine, a proof, and the like. It can be suitably used for a pattern forming method.
In particular, since the photosensitive film has a uniform thickness, the film is more precisely laminated on the substrate when a permanent pattern is formed.

  In addition, there is no restriction | limiting in particular as exposure to the laminated body which has the said photosensitive layer, According to the objective, it can select suitably, For example, the said photosensitive layer is exposed via the said support body, cushion layer, and PC layer. The photosensitive layer may be exposed through the cushion layer and the PC layer after the support is peeled off. After the support and the cushion layer are peeled off, the photosensitive layer may be exposed through the PC layer. The photosensitive layer may be exposed, and the photosensitive layer may be exposed after the support, the cushion layer, and the PC layer are peeled off.

[Development process]
The developing step is a step of forming a permanent pattern by exposing the photosensitive layer by the exposing step, curing the exposed region of the photosensitive layer, and then developing by removing the uncured region.

  There is no restriction | limiting in particular as the removal method of the said unhardened area | region, According to the objective, it can select suitably, For example, the method etc. which remove using a developing solution are mentioned.

  The developer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include alkali metal or alkaline earth metal hydroxides or carbonates, bicarbonates, aqueous ammonia, and quaternary ammonium. A salt aqueous solution is preferred. Among these, an aqueous sodium carbonate solution is particularly preferable.

  The developer includes a surfactant, an antifoaming agent, an organic base (for example, benzylamine, ethylenediamine, ethanolamine, tetramethylammonium hydroxide, diethylenetriamine, triethylenepentamine, morpholine, triethanolamine, etc.) May be used in combination with an organic solvent (for example, alcohols, ketones, esters, ethers, amides, lactones, etc.). The developer may be an aqueous developer obtained by mixing water or an aqueous alkali solution and an organic solvent, or may be an organic solvent alone.

[Curing process]
The curing treatment step is a step of performing a curing treatment on the photosensitive layer in the formed permanent pattern after the development step is performed.

  There is no restriction | limiting in particular as said hardening process, Although it can select suitably according to the objective, For example, a whole surface exposure process, a whole surface heat processing, etc. are mentioned suitably.

Examples of the entire surface exposure processing method include a method of exposing the entire surface of the laminate on which the permanent pattern is formed after the developing step. The entire surface exposure accelerates the curing of the resin in the photosensitive composition forming the photosensitive layer, and the surface of the permanent pattern is cured.
There is no restriction | limiting in particular as an apparatus which performs the said whole surface exposure, Although it can select suitably according to the objective, For example, UV exposure machines, such as an ultrahigh pressure mercury lamp, are mentioned suitably.

Examples of the entire surface heat treatment method include a method of heating the entire surface of the laminate on which the permanent pattern is formed after the developing step. The entire surface heating increases the film strength of the surface of the permanent pattern.
As heating temperature in the said whole surface heating, 120-250 degreeC is preferable and 120-200 degreeC is more preferable. When the heating temperature is less than 120 ° C., the film strength may not be improved by heat treatment. When the heating temperature exceeds 250 ° C., the resin in the photosensitive composition is decomposed, and the film quality is weak and brittle. Sometimes.
The heating time in the entire surface heating is preferably 10 to 120 minutes, and more preferably 15 to 60 minutes.
There is no restriction | limiting in particular as an apparatus which performs the said whole surface heating, According to the objective, it can select suitably from well-known apparatuses, For example, a dry oven, a hot plate, IR heater etc. are mentioned.

When the substrate is a printed wiring board such as a multilayer wiring board, the permanent pattern of the present invention can be formed on the printed wiring board, and further soldered as follows.
That is, the development step forms a hardened layer that is the permanent pattern, and the metal layer is exposed on the surface of the printed wiring board. Gold plating is performed on the portion of the metal layer exposed on the surface of the printed wiring board, and then soldering is performed. Then, a semiconductor or a component is mounted on the soldered portion. At this time, the permanent pattern by the hardened layer exhibits a function as a protective film or an insulating film (interlayer insulating film), and prevents external impact and conduction between adjacent electrodes.

  In the permanent pattern forming method of the present invention, it is preferable to form at least one of a protective film and an interlayer insulating film. When the permanent pattern formed by the permanent pattern forming method is the protective film or the interlayer insulating film, the wiring can be protected from external impact and bending, particularly when the interlayer insulating film is the interlayer insulating film. Is useful for high-density mounting of semiconductors and components on, for example, multilayer wiring boards and build-up wiring boards.

  Since the permanent pattern forming method of the present invention can form a permanent pattern with high definition and efficiency by suppressing distortion of an image formed on the photosensitive layer, high-definition exposure is required. In particular, it can be suitably used for forming high-definition permanent patterns.

  Examples of the present invention will be described below, but the present invention is not limited to the following examples.

Example 1
-Preparation of photosensitive composition-
A photosensitive composition solution was prepared based on the following composition.
[Composition of photosensitive composition solution]
-Barium sulfate dispersion ⁽¹⁾ 66.7 parts by mass-PR300 (Propylene glycol monomethyl ether acetate solution containing 3% by mass of Solvesso 150 having a solid content of 68% by mass of epoxy acrylate manufactured by Showa Polymer Co., Ltd.)
36.38 parts by mass-76 mass% propylene glycol monomethyl ether acetate solution of dipentaerythritol hexaacrylate 20.96 parts by mass-IRGACURE 819 (manufactured by Ciba Specialty Chemicals)
5.07 parts by mass-Epicron EXA850S (Dainippon Ink Co., Ltd.) 7.36 parts by mass-DICY7 (Shikoku Kasei Co., Ltd.) 1.45 parts by mass-2 MAOK (Shikoku Kasei Co., Ltd.) 0.41 parts by mass-F780F (large) 30% by weight methyl ethyl ketone solution from Nippon Ink Co., Ltd.
0.17 parts by mass Blue pigment dispersion ⁽²⁾ 1.0 part by mass
40 parts by mass of methyl ethyl ketone (1): 30 parts by mass of barium sulfate (manufactured by Sakai Chemical Co., Ltd., B30), the above styrene / maleic anhydride / butyl acrylate copolymer (molar ratio: 40/32/28) and benzylamine ( 34.29 parts by mass of a 35 mass% methyl ethyl ketone solution of an addition reaction product with 1.0 equivalent to the anhydride group of the copolymer and 35.71 parts by mass of 1-methoxy-2-propyl acetate After mixing, a motor mill M-200 (manufactured by Eiger) was used by dispersing for 3.5 hours at a peripheral speed of 9 m / s using zirconia beads having a diameter of 1.0 mm.
(2): 14 parts by weight of a blue pigment (HELIOGEN BLUE L6700F; CI Pigment Blue 15: 6), 13.79 parts by weight of the PR300 (solid content 68% by weight solution), and propylene glycol monomethyl ether acetate 112. After 21 parts by mass were mixed in advance, the mixture was prepared by dispersing for 180 minutes at a peripheral speed of 9 m / s using zirconia beads having a diameter of 0.3 mm with a motor mill (M-200, manufactured by Eiger).

-Production of photosensitive film-
The obtained photosensitive composition solution was applied onto a PET (polyethylene terephthalate) film having a thickness of 20 μm as the support and dried to form a photosensitive layer having a thickness of 35 μm. Next, a 12 μm-thick polypropylene film was laminated as the protective film on the photosensitive layer to produce a photosensitive film. The halogen content of the photosensitive layer in the obtained photosensitive film was measured by the following method.

<Measurement of halogen content>
The photosensitive layer (10 g) of the produced photosensitive film is combusted in a combustion flask, the generated gas is absorbed into pure water, and the halogen content in the obtained absorbing solution is detected by ion chromatography. And quantified. The results are shown in Table 3.

-Formation of permanent pattern-
-Preparation of laminate-
Next, as a base material, a surface of a halogen-free copper-clad laminate (having no through holes and a copper thickness of 12 μm) on which wiring was formed was prepared by subjecting it to a chemical polishing treatment. A vacuum laminator (MVLP500, manufactured by Meiki Seisakusho Co., Ltd.) was used on the copper clad laminate while peeling off the protective film on the photosensitive film so that the photosensitive layer of the photosensitive film was in contact with the copper clad laminate. Lamination was performed to prepare a laminate in which the copper-clad laminate, the photosensitive layer, and the polyethylene terephthalate film (support) were laminated in this order.
The pressure bonding conditions were a pressure bonding temperature of 90 ° C., a pressure bonding pressure of 0.4 MPa, and a laminating speed of 1 m / min. The laminate property of the photosensitive film was evaluated by the following method.

<Lamination>
The laminate property of the photosensitive film was evaluated based on the following criteria. The results are shown in Table 3.
〔Evaluation criteria〕
A: Bubbles are observed in the photosensitive layer of the laminate.
Δ: Mixing of fine bubbles is observed in the photosensitive layer of the laminate.
X: Many air bubbles are mixed in the photosensitive layer of the laminate.

--Exposure process--
A pattern in which holes with different diameters are formed from a polyethylene terephthalate film (support) side with a laser beam having a wavelength of 405 nm from the side of the polyethylene terephthalate film (support) with respect to the photosensitive layer in the prepared laminate. Were irradiated and exposed to obtain a part of the photosensitive layer.

<< Pattern Forming Apparatus >>
27 to 32 as the light irradiating means, and 768 pairs of micromirror arrays in which 1024 micromirrors are arranged in the main scanning direction shown in FIG. 4 as the light modulating means are arranged in the sub-scanning direction. The microlens array 472 in which the DMD 50 controlled to drive only 1024 × 256 rows and the microlenses 474 whose one surface is a toric surface shown in FIG. A pattern forming apparatus having optical systems 480 and 482 for forming an image of light passing through the array on the photosensitive layer was used.

The toric surface of the microlens described below was used.
First, in order to correct the distortion on the exit surface of the microlens 474 as the picture element portion of the DMD 50, the strain on the exit surface was measured. The results are shown in FIG. In FIG. 14, the same height positions of the reflecting surfaces are shown connected by contour lines, and the pitch of the contour lines is 5 nm. Note that the x direction and the y direction shown in the figure are two diagonal directions of the micromirror 62, and the micromirror 62 rotates around a rotation axis extending in the y direction. 15A and 15B show the height position displacement of the reflecting surface of the micromirror 62 along the x direction and the y direction, respectively.

  As shown in FIGS. 14 and 15, there is distortion on the reflection surface of the micromirror 62, and when attention is paid particularly to the center of the mirror, distortion in one diagonal direction (y direction) is different from that in the other diagonal line. It can be seen that the distortion is larger than the distortion in the direction (x direction). Therefore, it can be seen that the shape of the laser beam B collected by the microlens 55a of the microlens array 55 is distorted in this state.

  FIGS. 16A and 16B show the front shape and the side shape of the entire microlens array 55 in detail. In these drawings, the dimensions of each part of the microlens array 55 are also entered, and the unit thereof is mm. As described above with reference to FIG. 4, the 1024 × 256 micromirrors 62 of the DMD 50 are driven. Correspondingly, the microlens array 55 has 1024 microlenses arranged in the horizontal direction. The 55a rows are arranged in parallel in 256 rows in the vertical direction. In FIG. 9A, the arrangement order of the microlens array 55 is indicated by j in the horizontal direction and k in the vertical direction.

  17A and 17B show a front shape and a side shape of one microlens 55a in the microlens array 55, respectively. In FIG. 9A, the contour lines of the micro lens 55a are also shown. The end surface of each microlens 55a on the light emitting side has an aspherical shape that corrects aberration due to distortion of the reflecting surface of the micromirror 62. More specifically, the micro lens 55a is a toric lens, and has a radius of curvature Rx = −0.125 mm in a direction optically corresponding to the x direction and a radius of curvature Ry = − in a direction corresponding to the y direction. 0.1 mm.

  Therefore, the condensing state of the laser beam B in the cross section parallel to the x direction and the y direction is roughly as shown in FIGS. 18A and 18B, respectively. That is, when the cross section parallel to the x direction is compared with the cross section parallel to the y direction, the radius of curvature of the microlens 55a is smaller and the focal length is shorter in the latter cross section. I understand that.

  19A, 19B, 19C, and 19D show simulation results of the beam diameter in the vicinity of the condensing position (focal position) of the microlens 55a when the microlens 55a has the above shape. For comparison, FIGS. 20a, 20b, 20c, and 20d show the results of a similar simulation when the microlens 55a has a spherical shape with a radius of curvature Rx = Ry = −0.1 mm. In addition, the value of z in each figure has shown the evaluation position of the focus direction of the micro lens 55a with the distance from the beam emission surface of the micro lens 55a.

The surface shape of the microlens 55a used for the simulation is calculated by the following calculation formula.

  In the above formula, Cx means the curvature in the x direction (= 1 / Rx), Cy means the curvature in the y direction (= 1 / Ry), and X is the lens optical axis in the x direction. The distance from O means Y, and Y means the distance from the lens optical axis O in the y direction.

  As is apparent when comparing FIGS. 19a to 19d and FIGS. 20a to 20d, the microlens 55a includes a toric lens in which the focal length in the cross section parallel to the y direction is smaller than the focal length in the cross section parallel to the x direction. As a result, distortion of the beam shape in the vicinity of the condensing position is suppressed. As a result, a higher-definition pattern without distortion can be exposed on the photosensitive layer 150. Moreover, it turns out that the area | region where a beam diameter is small is wider, ie, the depth of focus is larger in this embodiment shown to FIG.

  In addition, the aperture array 59 disposed in the vicinity of the condensing position of the microlens array 55 is disposed such that only light having passed through the corresponding microlens 55a is incident on each aperture 59a. That is, by providing this aperture array 59, it is possible to prevent light from adjacent microlenses 55a not corresponding to each aperture 59a from entering, and to increase the extinction ratio.

--Development process--
After standing at room temperature for 10 minutes, the polyethylene terephthalate film (support) is peeled off from the laminate, and a 1% by mass aqueous sodium carbonate solution is used as an alkaline developer on the entire surface of the photosensitive layer on the copper clad laminate. Developed at 30 ° C. for 60 seconds to dissolve and remove uncured regions. Thereafter, it was washed with water and dried to form a permanent pattern.

-Curing process-
The entire surface of the laminate on which the permanent pattern was formed was heated at 160 ° C. for 30 minutes to cure the surface of the permanent pattern and increase the film strength. When the permanent pattern was visually observed, no bubbles were observed on the surface of the permanent pattern.
The formed permanent pattern was evaluated for exposure sensitivity, resolution, and exposure speed. The results are shown in Table 3.

<Exposure sensitivity>
In the obtained permanent pattern, the thickness of the cured region of the remaining photosensitive layer was measured. Subsequently, a sensitivity curve is obtained by plotting the relationship between the irradiation amount of the laser beam and the thickness of the cured layer. From the sensitivity curve thus obtained, the thickness of the cured region on the wiring is 15 μm, and the amount of light energy when the surface of the cured region is a glossy surface is defined as the amount of light energy necessary for curing the photosensitive layer. Exposure sensitivity was used. As a result, the exposure sensitivity was 40 mJ / cm ² .

<Resolution>
The surface of the obtained printed circuit board on which the permanent pattern was formed was observed with an optical microscope, and the minimum hole diameter with no residual film in the hole portion of the cured layer pattern was measured. The smaller the numerical value, the better the resolution.
As a result, the resolution was 60 μm.

<Exposure speed>
Using the pattern forming apparatus, the speed at which the exposure light and the photosensitive layer were relatively moved was changed, and the speed at which the permanent pattern was formed was determined. Exposure was performed from the polyethylene terephthalate film (support) side with respect to the photosensitive layer in the prepared laminated body. It should be noted that an efficient permanent pattern can be formed at a higher setting speed.
As a result, the exposure speed was 32 mm / sec.

-Plating process-
The printed wiring board on which the permanent pattern had been formed was subjected to gold plating according to a conventional method and then subjected to a water-soluble flux treatment. Subsequently, it was immersed three times in a solder bath set at 260 ° C. for 5 seconds, and the flux was removed by washing with water.

<Solder heat resistance>
About the permanent pattern after the said flux removal, peeling, the swelling, and discoloration of the cured film in a pattern were observed visually, and solder heat resistance was evaluated by the following references | standards. The results are shown in Table 3.
〔Evaluation criteria〕
○: Peeling, blistering, and discoloration of the cured film are not observed. Δ: Peeling, blistering, and discoloration of the cured film are slightly recognized.

<Pencil hardness>
About the permanent pattern after the said flux removal, pencil hardness was measured based on JISK-5400. As a result, the pencil hardness was 5H. The results are shown in Table 3.

<Storage stability>
The produced photosensitive film was stored for 2 months under a temperature condition of 5 ° C. Two months later, exposure sensitivity and resolution were measured, developability was evaluated, and storage stability was evaluated based on the following criteria. The evaluation results are shown in Table 3.
〔Evaluation criteria〕
A: Almost no change in exposure sensitivity and resolution, and excellent storage stability.
Δ: Either exposure sensitivity or resolution decreases, development becomes difficult, and storage stability is inferior.
X: Exposure sensitivity and resolution are remarkably lowered, development is impossible, storage stability is extremely inferior, or storage is impossible.

(Example 2)
In Example 1, the blue pigment dispersion in the photosensitive composition solution was mixed with 7 parts by weight of the blue pigment (CI Pigment Blue 15: 6) and a yellow pigment (manufactured by CLARIANT, PALIOTOL YELLOW D1155, C Pigment Yellow 185) A photosensitive composition was prepared in the same manner as in Example 1 except that the dispersion (green dispersion) was prepared using 7 parts by weight. did.

Using the obtained photosensitive film, a permanent pattern was formed in the same manner as in Example 1. When the surface of the permanent pattern was visually observed, no bubbles were observed on the surface of the cured film in the permanent pattern.
Further, the halogen content and laminating properties of the photosensitive layer in the photosensitive film were evaluated in the same manner as in Example 1. The results are shown in Table 3.
About the obtained said permanent pattern, by the method similar to Example 1, exposure sensitivity, resolution, exposure speed, and pencil hardness were measured, and solder heat resistance was evaluated. The results are shown in Table 3.
Furthermore, the storage stability of the photosensitive film was evaluated by the same method as in Example 1. The results are shown in Table 3.

(Example 3)
In Example 1, the blue pigment dispersion in the photosensitive composition solution was used as a blue pigment dispersion using 14 parts by weight of a blue pigment (BASF Corporation, HELIOGEN BLUE D707, CI Pigment Blue 15: 3). A photosensitive composition was prepared in the same manner as in Example 1 except for preparing a photosensitive film.

Using the obtained photosensitive film, a permanent pattern was formed in the same manner as in Example 1. When the surface of the permanent pattern was visually observed, no bubbles were observed on the surface of the cured film in the permanent pattern.
Further, the halogen content and laminating properties of the photosensitive layer in the photosensitive film were evaluated in the same manner as in Example 1. The results are shown in Table 3.
About the obtained said permanent pattern, by the method similar to Example 1, exposure sensitivity, resolution, exposure speed, and pencil hardness were measured, and solder heat resistance was evaluated. The results are shown in Table 3.
Furthermore, the storage stability of the photosensitive film was evaluated by the same method as in Example 1. The results are shown in Table 3.

Example 4
In Example 1, the blue pigment dispersion in the photosensitive composition solution was used in an amount of 14 parts by weight of blue pigment (Ciba Specialty Chemicals, IRUGAZIN BLUE X3367, CI Pigment Blue 15: 2). In the same manner as in Example 1 except that a blue pigment dispersion was prepared, a photosensitive composition was prepared to produce a photosensitive film.

Using the obtained photosensitive film, a permanent pattern was formed in the same manner as in Example 1. When the surface of the permanent pattern was visually observed, no bubbles were observed on the surface of the cured film in the permanent pattern.
Further, the halogen content and laminating properties of the photosensitive layer in the photosensitive film were evaluated in the same manner as in Example 1. The results are shown in Table 3.
About the obtained said permanent pattern, by the method similar to Example 1, exposure sensitivity, resolution, exposure speed, and pencil hardness were measured, and solder heat resistance was evaluated. The results are shown in Table 3.
Furthermore, the storage stability of the photosensitive film was evaluated by the same method as in Example 1. The results are shown in Table 3.

(Example 5)
In Example 1, the photosensitive film was manufactured by the method similar to Example 1 except having replaced the said photosensitive composition solution with the photosensitive composition solution which consists of the following composition. The photosensitive composition solution was prepared by stirring the following composition with a small mixer AR100 manufactured by Sinky Corporation for 15 minutes.

[Composition of photosensitive composition solution]
-Barium sulfate aqueous solution ⁽¹⁾ 24.75 parts by mass-Styrene / maleic anhydride / butyl acrylate copolymer (molar ratio 40/32/28)
35% by weight methyl ethyl ketone of an addition reaction product of benzylamine (0.7 equivalent with respect to the anhydride group of the copolymer) and styrylamine (0.3 equivalent with respect to the anhydride group of the copolymer) Solution ⁽²⁾ 13.36 parts by mass-76 mass% propylene glycol monomethyl ether acetate solution of dipentaerythritol hexaacrylate 6.04 parts by mass-IRGACURE 819 (manufactured by Ciba Specialty Chemicals) 1.98 parts by mass-F780F (large) 30% by weight methyl ethyl ketone solution from Nippon Ink Co., Ltd.
0.066 parts by mass Green pigment dispersion ⁽³⁾ 1.0 part by mass
Methyl ethyl ketone 60.00 parts by mass (1): 30 parts by mass of barium sulfate (manufactured by Sakai Chemical Co., Ltd., B30) and the styrene / maleic anhydride / butyl acrylate copolymer (molar ratio 40/32/28) ) And benzylamine (0.7 equivalents relative to the anhydride group of the copolymer) and styrylamine (0.3 equivalents relative to the anhydride group of the copolymer) to 35% by mass of the addition reaction product 34.29 parts by mass of a methyl ethyl ketone solution and 35.71 parts by mass of propylene glycol monomethyl ether acetate were mixed in advance, and then a motor mill (M-200, manufactured by Eiger) was used to make zirconia beads having a diameter of 0.3 mm. It was prepared by dispersing for 210 minutes at a speed of 9 m / s.
(2): A 35% by mass methyl ethyl ketone solution of a maleamic acid copolymer having units A and B represented by the following structural formula (1). The unit A consists of two structural units, R ¹ in one of the structural units of which are phenyl, R ¹ in the other structural units are butyloxycarbonyl, R ³ and R ⁴ are hydrogen atoms. R ² in unit B is benzyl or styryl. The mole fraction x of the repeating unit in the unit A is 40 mol% for the one constituent unit, and 28 mol% for the other constituent unit, and the mole fraction y of the repeating unit in the unit B is Is 32 mol%. The molar fraction of benzyl is 70 mol%, and the molar fraction of styryl is 30 mol%.
(3): 7 parts by weight of a blue pigment (HELIOGEN BLUE L6700F; CI Pigment Blue 15: 6), 7 parts by weight of a yellow pigment (CLARIANT, PALIOTOL YELLOW D1155, CI Pigment Yellow 185), 13.79 parts by mass of a 35 mass% methyl ethyl ketone solution of the maleamic acid copolymer (2) and 112.21 parts by mass of propylene glycol monomethyl ether acetate were mixed in advance, and then a motor mill (M-200, Eiger Corporation). And zirconia beads having a diameter of 0.3 mm, and dispersed for 180 minutes at a peripheral speed of 9 m / s.

Using the obtained photosensitive film, a permanent pattern was formed in the same manner as in Example 1. When the surface of the permanent pattern was visually observed, no bubbles were observed on the surface of the cured film in the permanent pattern.
Further, the halogen content and laminating properties of the photosensitive layer in the photosensitive film were evaluated in the same manner as in Example 1. The results are shown in Table 3.
About the obtained said permanent pattern, by the method similar to Example 1, exposure sensitivity, resolution, exposure speed, and pencil hardness were measured, and solder heat resistance was evaluated. The results are shown in Table 3.
Furthermore, the storage stability of the photosensitive film was evaluated by the same method as in Example 1. The results are shown in Table 3.

(Comparative Example 1)
In Example 1, the same method as in Example 1 except that the blue pigment of the blue pigment dispersion in the photosensitive composition was replaced with a halogen-containing green pigment (HOSTAPERM GREEN GG01, CI Pigment Green 7). Thus, a photosensitive composition was prepared to produce a photosensitive film.

Using the obtained photosensitive film, a permanent pattern was formed in the same manner as in Example 1. When the surface of the permanent pattern was visually observed, no bubbles were observed on the surface of the cured film in the permanent pattern.
Further, the halogen content and laminating properties of the photosensitive layer in the photosensitive film were evaluated in the same manner as in Example 1. The results are shown in Table 3.
About the obtained said permanent pattern, by the method similar to Example 1, exposure sensitivity, resolution, exposure speed, and pencil hardness were measured, and solder heat resistance was evaluated. The results are shown in Table 3.
Furthermore, the storage stability of the photosensitive film was evaluated by the same method as in Example 1. The results are shown in Table 3.

(Comparative Example 2)
In the pattern forming apparatus in Comparative Example 1, a photosensitive composition was prepared by the same method as in Comparative Example 1 except that the microlens array was not used, a photosensitive film was produced, and a permanent pattern was formed.
About the obtained said permanent pattern, by the method similar to Example 1, exposure sensitivity, resolution, exposure speed, and pencil hardness were measured, and solder heat resistance was evaluated. The results are shown in Table 3.

(Comparative Example 3)
In the pattern forming apparatus in Example 4, a photosensitive composition was prepared by the same method as in Example 4 except that the microlens array was not used, a photosensitive film was produced, and a permanent pattern was formed.
About the obtained said permanent pattern, by the method similar to Example 1, exposure sensitivity, resolution, exposure speed, and pencil hardness were measured, and solder heat resistance was evaluated. The results are shown in Table 3.

(Comparative Example 4)
In the pattern forming apparatus in Example 5, a photosensitive composition was prepared by the same method as in Example 5 except that the microlens array was not used, a photosensitive film was produced, and a permanent pattern was formed.
About the obtained said permanent pattern, by the method similar to Example 1, exposure sensitivity, resolution, exposure speed, and pencil hardness were measured, and solder heat resistance was evaluated. The results are shown in Table 3.

* PB: Pigment Blue, PY: Pigment Yellow, PG: Pigment Green

From the results of Table 3, the photosensitive layers of Examples 1 to 5 manufactured using pigments containing no halogen compared to the photosensitive layers of Comparative Examples 1 and 2 manufactured using conventional pigments have extremely high halogen content. Therefore, it is thought that the generation of toxic gas is suppressed even if incinerated. Further, it was found that the film characteristics of the permanent pattern formed by exposing the photosensitive layer formed using the colorant containing no halogen atom are good, and the storage stability as a photosensitive film is also excellent.
Moreover, it is clear that Comparative Examples 3 to 4 and Comparative Example 2 exposed using a pattern forming apparatus that does not include a microlens array are inferior in resolution and exposure speed as compared with Examples 4 to 5 and Comparative Example 1. It was.

  The method for forming a permanent pattern of the present invention is capable of forming a cured film that has excellent film properties and does not generate toxic gas during incineration, and suppresses distortion of an image formed on the photosensitive layer, thereby providing a package substrate. It is possible to provide a permanent pattern forming method capable of efficiently and precisely forming a permanent pattern (a protective film such as an interlayer insulating film or a solder resist pattern) in the printed wiring board field including a high-definition exposure. It can be suitably used for forming various patterns to be used, and can be particularly suitably used for forming a high-definition permanent pattern.

FIG. 1 is an example of a partially enlarged view showing a configuration of a digital micromirror device (DMD). 2A and 2B are examples of explanatory diagrams for explaining the operation of the DMD. FIGS. 3A and 3B are examples of plan views showing the arrangement of the exposure beam and the scanning line in a case where the DMD is not inclined and in a case where the DMD is inclined. 4A and 4B are examples of diagrams illustrating examples of DMD usage areas. FIG. 5 is an example of a plan view for explaining an exposure method in which the photosensitive layer is exposed by one scanning by the scanner. 6A and 6B are examples of plan views for explaining an exposure method for exposing a photosensitive layer by a plurality of scans by a scanner. FIG. 7 is an example of a schematic perspective view illustrating an appearance of an example of the pattern forming apparatus. FIG. 8 is an example of a schematic perspective view illustrating the configuration of the scanner of the pattern forming apparatus. FIG. 9A is an example of a plan view showing an exposed region formed on the photosensitive layer, and FIG. 9B is an example of a diagram showing an array of exposure areas by each exposure head. FIG. 10 is an example of a perspective view showing a schematic configuration of an exposure head including light modulation means. FIG. 11 is an example of a sectional view in the sub-scanning direction along the optical axis showing the configuration of the exposure head shown in FIG. FIG. 12 is an example of a controller that controls DMD based on pattern information. FIG. 13A is an example of a cross-sectional view along the optical axis showing the configuration of another exposure head having a different coupling optical system, and FIG. 13B shows the exposure when a microlens array or the like is not used. FIG. 13C is an example of a plan view showing a light image projected on the surface to be exposed when a microlens array or the like is used. FIG. 14 is an example of a diagram showing the distortion of the reflection surface of the micromirror constituting the DMD with contour lines. FIGS. 15A and 15B are examples of graphs showing the distortion of the reflection surface of the micromirror in the two diagonal directions of the mirror. FIG. 16 is an example of a front view (A) and a side view (B) of a microlens array used in the pattern forming apparatus. FIG. 17 is an example of a front view (A) and a side view (B) of the microlens constituting the microlens array. FIG. 18 is an example of a schematic diagram illustrating a condensing state by a microlens in one cross section (A) and another cross section (B). FIG. 19a is an example of a diagram showing the result of simulating the beam diameter in the vicinity of the condensing position of the microlens of the present invention. FIG. 19B is an example of a diagram showing the same simulation result as that in FIG. 19A at another position. FIG. 19c is an example of a diagram showing the same simulation result as in FIG. 19a at another position. FIG. 19d is an example of a diagram showing the same simulation result as in FIG. 19a at another position. FIG. 20a is an example of a diagram showing the result of simulating the beam diameter in the vicinity of the condensing position of the microlens in the conventional pattern forming method. FIG. 20b is an example of a diagram showing the same simulation result as in FIG. 20a at another position. FIG. 20c is an example of a diagram showing the same simulation result as in FIG. 20a for another position. FIG. 20d is an example of a diagram illustrating simulation results similar to those in FIG. 20a at different positions. FIG. 21 is an example of a plan view showing another configuration of the combined laser light source. FIG. 22 shows an example of a front view (A) and an example of a side view (B) of the microlens constituting the microlens array. FIG. 23 is an example of a schematic diagram illustrating a light condensing state by the microlens of FIG. 22 in one cross section (A) and another cross section (B). FIG. 24 is an example of an explanatory diagram about the concept of correction by the light amount distribution correction optical system. FIG. 25 is an example of a graph showing the light amount distribution when the light irradiation means has a Gaussian distribution and the light amount distribution is not corrected. FIG. 26 is an example of a graph showing the light amount distribution after correction by the light amount distribution correcting optical system. 27A (A) is a perspective view showing the configuration of the fiber array light source, FIG. 27A (B) is an example of a partially enlarged view of (A), and FIGS. 27A (C) and (D) are lasers. It is an example of the top view which shows the arrangement | sequence of the light emission point in an emission part. FIG. 27 b is an example of a front view showing the arrangement of light emitting points in the laser emission part of the fiber array light source. FIG. 28 is an example of a diagram illustrating a configuration of a multimode optical fiber. FIG. 29 is an example of a plan view showing the configuration of the combined laser light source. FIG. 30 is an example of a plan view showing the configuration of the laser module. FIG. 31 is an example of a side view showing the configuration of the laser module shown in FIG. 32 is a partial side view showing the configuration of the laser module shown in FIG. FIG. 33 is an example of a perspective view showing a configuration of a laser array. FIG. 34A is an example of a perspective view showing a configuration of a multi-cavity laser, and FIG. 34B is a perspective view of a multi-cavity laser array in which the multi-cavity lasers shown in FIG. It is an example. FIG. 35 is an example of a plan view showing another configuration of the combined laser light source. FIG. 36A is an example of a plan view illustrating another configuration of the combined laser light source, and FIG. 36B is an example of a cross-sectional view along the optical axis of FIG. FIGS. 37A and 37B are examples of cross-sectional views along the optical axis showing the difference between the depth of focus in the conventional exposure apparatus and the depth of focus by the permanent pattern forming method (pattern forming apparatus) of the present invention. . FIG. 38 is a front view (A) and a side view (B) showing another example of the microarray lens constituting the macroarray. FIG. 39 is an example of a front view (A) and an example of a side view (B) of a microarray lens constituting a macroarray. FIG. 40 is a graph showing a spherical lens shape example. FIG. 41 is a graph showing another lens surface shape example. FIG. 42 is a perspective view showing another example of the microarray lens array. FIG. 43 is a plan view showing another example of the microarray lens array. FIG. 44 is a plan view showing another example of the microarray lens array. 45A to 45C are longitudinal sectional views showing other examples of the microarray lens array.

Explanation of symbols

LD1-LD7 GaN-based semiconductor laser 10 Heat block 11-17 Collimator lens 20 Condensing lens 30-31 Multimode optical fiber 44 Collimator lens holder 45 Condensing lens holder 46 Fiber holder 50 Digital micromirror device (DMD)
52 Lens system 53 Reflected light image (exposure beam)
54 Lens of second imaging optical system 55 Micro lens array 55a ', 55a''Micro lens 56 Surface to be exposed (scanning surface)
57 Lens of the second imaging optical system 58 Lens of the second imaging optical system 59 Aperture array 64 Laser module 66 Fiber array light source 67 Lens system 68 Laser emitting portion 69 Mirror 70 Prism 73 Combination lens 74 Imaging lens 100 Heat block 110 Multicavity laser 111 Heat block 113 Rod lens 120 Condensing lens 130 Multimode optical fiber 130a Core 140 Laser array 144 Light irradiation means 150 Photosensitive layer 152 Stage 155a Microlens 156 Installation stand 158 Guide 160 Gate 162 Scanner 164 Sensor 166 Exposure head 168 Exposure area 170 Exposed area 180 Heat block 184 Collimating lens array 302 Controller 304 Stage driving device 3 55 Micro lens array 355a Micro lens 454 Lens system 455 Micro lens array 455a Micro lens 468 Exposure area 472 Micro lens array 476 Aperture array 478 Aperture 480 Lens system 555 Micro lens array 555a Micro lens 655 Micro lens array 655a Micro lens 755 Micro lens array 755a micro lens

Claims (26)

Using a photosensitive composition containing at least a binder, a polymerizable compound, a photopolymerization initiator, a thermal crosslinking agent, and a colorant, wherein the colorant is substantially free of halogen atoms, After forming the photosensitive layer on the photosensitive layer,
After modulating the light from the light irradiating means by the light modulating means having n picture elements for receiving and emitting the light from the light irradiating means, it is possible to correct aberration due to the distortion of the exit surface in the picture element. A method for forming a permanent pattern, comprising exposing and developing through a microlens array in which microlenses having aspherical surfaces are arranged. Using a photosensitive composition containing at least a binder, a polymerizable compound, a photopolymerization initiator, a thermal crosslinking agent, and a colorant, wherein the colorant is substantially free of halogen atoms, After forming the photosensitive layer on the photosensitive layer,
A lens that does not allow light from the peripheral part of the picture element part to be incident after the light from the light irradiation part is modulated by a light modulation part having n picture element parts that receive and emit light from the light irradiation means A method for forming a permanent pattern, comprising exposing and developing through a microlens array in which microlenses having aperture shapes are arranged.   The method for forming a permanent pattern according to claim 2, wherein the microlens has an aspherical surface capable of correcting aberration due to distortion of the exit surface in the pixel portion.   4. The permanent pattern forming method according to claim 1, wherein the aspherical surface is a toric surface.   The pattern forming method according to claim 2, wherein the lens opening shape is circular.   The pattern forming method according to claim 2, wherein the lens opening shape is defined by providing a light shielding portion on the lens surface.   The permanent pattern forming method according to claim 1, wherein the colorant is a phthalocyanine pigment.   The method for forming a permanent pattern according to any one of claims 1 to 7, wherein the photosensitive layer is formed by applying a photosensitive composition to the surface of a substrate and drying.   The photosensitive layer is formed by laminating a photosensitive film having a support and a photosensitive layer obtained by laminating a photosensitive composition on the support on the surface of the substrate under at least one of heating and pressing. The permanent pattern forming method according to claim 1, wherein the permanent pattern forming method is performed.   The permanent pattern forming method according to claim 9, wherein the support includes a synthetic resin and is transparent.   The permanent pattern forming method according to claim 9, wherein the support has an elongated shape.   The method for forming a permanent pattern according to claim 9, wherein the photosensitive film has a long shape and is wound in a roll shape.   The permanent pattern formation method in any one of Claim 9 to 12 in which a photosensitive film has a protective film on a photosensitive layer.   The method for forming a permanent pattern according to claim 1, wherein the photosensitive layer has a thickness of 3 to 100 μm.   The permanent pattern forming method according to claim 1, wherein the base material is a printed wiring board on which wiring has been formed.   16. The light modulation means is capable of controlling any less than n number of image elements arranged continuously from n image elements in accordance with pattern information. A permanent pattern forming method.   The permanent pattern forming method according to claim 1, wherein the light modulation means is a spatial light modulation element.   The permanent pattern formation method according to claim 17, wherein the spatial light modulation element is a digital micromirror device (DMD).   The permanent pattern formation method according to claim 1, wherein the exposure is performed through an aperture array.   The permanent pattern formation method according to claim 1, wherein the exposure is performed while relatively moving the exposure light and the photosensitive layer.   The permanent pattern formation method according to any one of claims 1 to 20, wherein the light irradiation means can irradiate by combining two or more lights.   The light irradiation means includes a plurality of lasers, a multimode optical fiber, and a collective optical system for condensing and coupling the laser beams irradiated from the plurality of lasers to the multimode optical fiber. The permanent pattern formation method in any one of 21.   The permanent pattern forming method according to claim 22, wherein the wavelength of the laser beam is 395 to 415 nm.   The permanent pattern forming method according to claim 1, wherein after the development, the photosensitive layer is subjected to a curing process.   The permanent pattern formation method according to claim 24, wherein the curing process is at least one of a whole surface exposure process and a whole surface heat treatment performed at 120 to 200 ° C. 26. The permanent pattern forming method according to claim 1, wherein at least one of a protective film and an interlayer insulating film is formed.