JP2008211156A - Multilayer film, grooved multilayer film, wired multilayer film, method for manufacturing wired multilayer film, method for manufacturing wiring sheet, and method for manufacturing wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer film for forming a wiring pattern of a wiring board which can maintain high resolution of a photosensitive resin film, can form a wiring pattern of 30 μm or less, has high adhesiveness between the photosensitive resin film and a resin film, and is suited to mobile communication equipment, semiconductor element storing packages, etc., and to provide a wired multilayer film. <P>SOLUTION: An adhesive resin layer 5 having total reflectivity of 16% or less against ultraviolet rays (e.g., i rays) and having adhesiveness is formed on the main surface of a resin film 3 and a photosensitive resin film 7 is formed on the main surface of the adhesive resin layer 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a multilayer film, a grooved multilayer film, and a multilayer film with wiring, for producing a wiring pattern of a wiring board suitable for a mobile communication device, a package for housing semiconductor elements, and the like. The present invention also relates to a method for producing a multilayer film with wiring, a method for producing a wiring sheet, and a method for producing a wiring board.

  For wiring boards applied to semiconductor element storage packages for mounting semiconductor elements such as ICs and LSIs, and hybrid integrated circuit devices on which various electronic components are mounted, wiring circuits are required for miniaturization and high performance. Since it is necessary to form it with high density, miniaturization of the wiring width is further advanced. Also, higher speed is required for signals flowing through the wiring.

  For example, a photosensitive resin is used for the formation of the wiring, and in addition to the wiring substrate, the photosensitive resin is also frequently used for manufacturing a semiconductor element.

  This photosensitive resin was not irradiated with light by removing the light-irradiated part and the negative-type photosensitive resin used when the light-irradiated part was cured to leave an image and the remaining part was removed. There are positive-type photosensitive resins in which the portions remain as images, and they are properly used according to the respective characteristics.

  These photosensitive resins include those in liquid form and what are called dry film resists in the form of thin films, and are generally mainly used in the field of semiconductor elements and flat panel displays depending on the thickness and form of wiring. A positive type liquid type is used, and in the field of wiring substrates, a negative type dry film resist is mainly used.

  Also, the negative photosensitive resin film is widely used in the production of printed wiring boards. In the printed wiring board manufacturing method, wiring is mainly formed using a photosensitive resin film, and FR4 serving as an insulating board is used. A copper foil to be a conductor pattern is laminated, a photosensitive resin film is laminated on the Cu foil, and a wiring pattern is formed by performing exposure, development, and Cu etching, and a general printed wiring board is obtained.

  Such a negative photosensitive resin film has adhesiveness, and is used by directly bonding the photosensitive resin film on the Cu foil.

  In the formation of a wiring pattern using such a negative photosensitive resin film, it is required to increase the reflectance with respect to ultraviolet rays (for example, i-line) of a member disposed below the photosensitive resin film. Thus, a well-shaped photosensitive resin film (eg, solder resist) opening can be formed.

  On the other hand, it is good for photosensitive resin film (eg, solder resist) by exposing from the back side of the substrate, even when the reflectance of ultraviolet rays of the member arranged below the photosensitive resin film is small It has also been proposed to form a simple opening (see, for example, Patent Document 1).

  For example, in the formation of a wiring pattern using a positive type photosensitive resin film, it is desirable that the reflectance of the member (base material) disposed below the photosensitive resin film with respect to ultraviolet rays is small, and thus a good An opening of the photosensitive resin film can be formed.

  This positive type photosensitive resin is used by applying a liquid photosensitive resin to an object such as a PET film. Generally, a photosensitive resin tends to have too high adhesion to a PET film. If the adhesiveness is too high, it is difficult to remove the photosensitive resin film in the photosensitive resin film peeling step. Therefore, a liquid photosensitive resin is applied after a release agent such as silicone oil is applied to the surface of an object such as a PET film.

  At present, in order to form a finer wiring by applying the wiring forming method using the photosensitive resin film, a ceramic green sheet (for example, see Patent Document 2) or a metal plate (for example, see Patent Document 3). ), A photosensitive resin film is formed on the surface of a substrate such as a resin film (see, for example, Patent Document 4), exposed to light, and developed to form a groove by the photosensitive resin film. A wiring circuit is formed by forming a metal conductor by plating or filling a conductor paste.

  At this time, when a ceramic green sheet is used as the base material, it is necessary to immerse the ceramic green sheet in an alkaline solution when developing and peeling the photosensitive resin film. Cause. Further, when the base material is a metal plate, there is a drawback that it is heavy, is flexible, and easily corrodes.

  In view of the above points, currently, resin films that are lightweight, flexible, and hardly corrode are mainly used.

When a photosensitive resin film is formed on the surface of the resin film and exposed and developed to form a groove by the photosensitive resin film, exposure is performed by irradiating with ultraviolet rays through a glass mask having a desired pattern. The portion is formed by developing with an alkaline aqueous solution or the like.
JP-A-7-38233 JP-A-4-283946 Japanese Patent Laid-Open No. 7-122839 JP 2002-134881 A

  However, in the case of a negative type photosensitive resin film, when a resin having a very low reflectance is used as a base material, since the reflection of ultraviolet light is small, the contact portion between the photosensitive resin film and the base material is affected by ultraviolet light. There was a problem that the curing and crosslinking reaction of the photosensitive resin film became insufficient, and the adhesive strength between the substrate and the photosensitive resin film was lowered.

  In particular, in the case of a resin film such as PET that has been subjected to a mold release treatment such as silicon oil, the adhesiveness of the photosensitive resin film to a resin film such as PET is low, so when a wiring pattern having a line width of 30 μm or less is formed. There is a problem that the pattern of the photosensitive resin is easily peeled off from a resin film such as PET during the development processing using an aqueous alkali solution.

  Therefore, for example, in the case of a resin film such as PET, when a film having a large total reflectivity with respect to ultraviolet rays, for example, a PET film having a total reflectivity with respect to ultraviolet rays exceeding 16%, is exposed to ultraviolet rays, a photosensitive resin The ultraviolet rays that have passed through the film are reflected on the surface of the PET film, and the reflected ultraviolet rays are irradiated again on the photosensitive resin film, thereby suppressing undercut and preventing the photosensitive resin film from peeling off.

  However, when a film having a large total reflectance is used, there is a problem that the resolution of the photosensitive resin film pattern is lowered due to diffuse reflection and regular reflection of ultraviolet rays on the film surface and inside.

  In the case of a positive type photosensitive resin film, for example, when an exposure process using ultraviolet light is performed using a PET film having a total reflectance of more than 16%, the ultraviolet light transmitted through the photosensitive resin film is reflected on the surface of the PET film and The pattern of the photosensitive resin film on the contact surface with the PET film is dissolved during the development process using the alkaline aqueous solution by reflecting the reflected ultraviolet ray inside and irradiating the reflected ultraviolet ray to the photosensitive resin film again. There is a so-called undercut that is difficult to form.

  Furthermore, since a positive type photosensitive resin is generally used in a liquid form, if a liquid type is used, a film is formed on the surface of a film such as PET that has been subjected to a release treatment such as silicon oil by a spin coating method or the like. When forming, repelling and bleeding occurred, and there was a problem that it was difficult to form a smooth and good film.

  Further, the positive type photosensitive resin film has excessively high adhesiveness and requires a release agent such as silicone oil. However, when such a release agent is used, the adhesiveness becomes too low. There was also a problem.

  Therefore, the present invention maintains high resolution of both negative type and positive type photosensitive resin films, can form a wiring pattern of 30 μm or less, and has good adhesion between the photosensitive resin film and the resin film. It is an object of the present invention to provide a multilayer film, a multilayer film with a groove, and a multilayer film with a wiring for producing a wiring pattern of a wiring board suitable for a machine or a package for housing a semiconductor element.

  Moreover, this invention aims at providing the manufacturing method of the multilayer film with wiring using said multilayer film, the manufacturing method of a wiring sheet, and the manufacturing method of a wiring board.

  In the multilayer film of the present invention, an adhesive resin layer having a total reflectance of 16% or less with respect to ultraviolet rays is formed on the main surface of the resin film, and a photosensitive resin film is formed on the main surface of the adhesive resin layer. Characteristic multilayer film.

  Moreover, as for the multilayer film of this invention, it is desirable for the thickness of the said photosensitive resin film to be 10-50 micrometers.

  The grooved multilayer film of the present invention is characterized in that grooves are formed in the photosensitive resin film of the multilayer film described above.

  Moreover, as for the multilayer film with a groove | channel of this invention, it is desirable for the width | variety of the said groove | channel to become narrow at the opening side in the depth direction.

  In the grooved multilayer film of the present invention, it is desirable that the photosensitive resin film is a positive type, and the width of the groove is wider on the opening side in the depth direction.

  In the grooved multilayer film of the present invention, the width of the narrow portion of the groove is desirably 95 or more when the width of the widest portion of the groove is 100.

  Moreover, the multilayer film with wiring of the present invention is characterized in that a wiring is formed by forming a conductor in the groove of the above-mentioned grooved multilayer film.

  In the multilayer film with wiring of the present invention, the conductor is preferably a conductor paste.

  In the method for producing a multilayer film with wiring of the present invention, an adhesive resin layer having a total reflectance of 16% or less with respect to ultraviolet rays is formed on the main surface of the resin film, and a photosensitive resin film is formed on the main surface of the adhesive resin layer. Forming a multilayer film in which the adhesive resin layer is formed on the main surface of the resin film and the photosensitive resin film is formed on the main surface of the adhesive resin layer; and the photosensitive resin Irradiating the film with light corresponding to a desired wiring pattern; developing the photosensitive resin film; removing a portion of the photosensitive resin film; and forming grooves in the photosensitive resin film of the multilayer film. And a step of forming a wiring by forming a conductor in the groove.

  The method for producing a wiring sheet of the present invention includes a step of removing the photosensitive resin film from the multilayer film with wiring produced by the above-described method for producing a multilayer film with wiring, and a multilayer with wiring from which the photosensitive resin film has been removed. A step of laminating a main surface of an insulating sheet on a main surface of the film on which the wiring is formed, and a step of producing a laminate; and a step of removing the resin film and the adhesive resin layer from the laminate. It is characterized by comprising.

  The manufacturing method of the wiring sheet of this invention covers the process of removing the said photosensitive resin film from the multilayer film with a wiring produced by the manufacturing method of the multilayer film with a wiring mentioned above, the said wiring, and the said adhesive resin layer. As described above, a step of applying an insulator-containing slurry containing an insulator, a step of solidifying the insulator-containing slurry to form an insulating sheet, and producing a laminate in which the wiring is embedded, and from the laminate A method for producing a wiring sheet, comprising: a step of removing a resin film and the adhesive resin layer.

  The method for manufacturing a wiring board according to the present invention includes a step of laminating a plurality of the wiring sheets produced by the above-described method for manufacturing a wiring sheet.

  The multilayer film of the present invention is a negative film formed on the main surface of the adhesive resin layer by disposing an adhesive resin layer having a total reflectance of 16% or less with respect to ultraviolet rays between the resin film and the photosensitive resin film. When the photosensitive resin film of the mold is irradiated with ultraviolet rays (for example, i-line = 365 nm), the adhesive resin layer and the photosensitive resin film are caused by the curing and crosslinking reaction of the photosensitive resin film and the adhesiveness of the adhesive resin layer. Since it is possible to suppress the peeling of the photosensitive resin film, which is a problem when the reflectance is lowered, wiring excellent in resolution with a line width of 30 μm or less suitable for a wiring board Can be formed. Furthermore, when the positive photosensitive resin film formed on the main surface of the adhesive resin layer is irradiated with ultraviolet rays, an adhesive resin layer having a total reflectance with respect to ultraviolet rays of 16% or less is disposed, thereby undercutting. A smooth, good photosensitive resin film free from cissing and bleeding is formed, and wiring with excellent resolution with a line width of 30 μm or less suitable for a wiring board can be formed.

  Further, according to the multilayer film of the present invention, the thickness of the photosensitive resin film is desirably in the range of 10 to 50 μm, and thereby, a thick wiring can be formed, so that the resistance of the wiring can be reduced. .

  In addition, the grooved multilayer film of the present invention has grooves formed on the photosensitive resin film of the multilayer film described above, and the groove having excellent resolution is formed and the photosensitive resin film is peeled off. Therefore, it is optimal for the production of wiring with high resolution and high wiring density.

  In particular, by narrowing the width of the groove on the opening side in the depth direction, after removing the photosensitive resin film after forming the wiring in the groove, the photosensitive resin film is not disturbed by the wiring. There is an advantage that it can be easily removed without applying an excessive load. This advantage is significant when a negative photosensitive resin film is used.

  Moreover, when the opening side of a groove | channel is wide, there exists an advantage that the filling property of a conductor paste improves. The same applies when the conductor is formed in the groove by plating.

  The grooved multilayer film of the present invention is such that the cross-sectional shape of the wiring is substantially rectangular by setting the width of the narrow portion of the groove to 95 or more when the width of the wide portion of the groove is 100. It becomes a conductor excellent in electrical characteristics (specific resistance, S21, etc.).

  In addition, the multilayer film with wiring of the present invention is suitably used for a wiring board or the like because wiring is formed by a conductor in a fine groove having excellent resolution.

  Moreover, according to the multilayer film with wiring of this invention, it can apply not only to a resin substrate but to a ceramic substrate by using a conductive paste as the conductor. Moreover, it becomes cheap compared with the case where the conductor formed by plating is used.

  In addition, according to the multilayer film with wiring of the present invention, by forming the wiring with a conductive paste, it becomes easy to cope with simultaneous firing with ceramics, so not only the wiring board using organic resin but also ceramics. The present invention can also be applied to a wiring board using an insulating substrate.

  Further, according to the method for producing a multilayer film with wiring of the present invention, an adhesive resin layer having a total reflectance of 16% or less with respect to ultraviolet rays is formed on the main surface of the resin film, and the main surface of the adhesive resin layer is exposed to light. Forming a photosensitive resin film, preparing a multilayer film in which the adhesive resin layer is formed on the main surface of the resin film, and the photosensitive resin film is formed on the main surface of the adhesive resin layer; Irradiating the photosensitive resin film with light corresponding to a desired wiring pattern; developing the photosensitive resin film; removing a part of the photosensitive resin film; and By easily forming a multilayer film with wiring provided with wiring of remarkably excellent resolution by providing a step of forming a groove in the resin film and a step of forming a wiring by forming a conductor in the groove. Can do.

  In addition, according to the method for manufacturing a wiring sheet of the present invention, the step of removing the photosensitive resin film from the multilayer film with wiring produced by the method for manufacturing the multilayer film with wiring described above, and the removal of the photosensitive resin film The step of laminating the main surface of the insulating sheet on the main surface of the multilayer film with wiring formed on the side where the wiring is formed, and producing the laminate, and the resin film and the adhesive resin layer from the laminate A wiring sheet provided with wiring with remarkably excellent resolution can be easily produced. For example, when a through conductor that penetrates the insulating sheet in the thickness direction with a conductor paste is provided in advance in the insulating sheet, the through conductor is compressed by the wiring when the wiring is embedded in the insulating sheet. Therefore, there is an advantage that the density of the through conductor is improved and the electric resistance is reduced.

  Moreover, according to the manufacturing method of the wiring sheet of this invention, the process of removing the said photosensitive resin film from the multilayer film with a wiring produced by the manufacturing method of the multilayer film with a wiring mentioned above, the said wiring, and the said adhesive resin A step of applying an insulator-containing slurry containing an insulator so as to cover the layer, a step of solidifying the insulator-containing slurry as an insulating sheet, and producing a laminate in which the wiring is embedded; By including the step of removing the resin film and the adhesive resin layer from the laminate, it is possible to easily produce a wiring sheet provided with wiring with remarkably excellent resolution. Further, since there is no need to deform the individual insulating sheet to embed the wiring, there is an advantage that a wiring sheet excellent in flatness can be easily produced.

  According to the method for manufacturing a wiring board of the present invention, a wiring board provided with wiring with remarkably excellent resolution by including a step of laminating the plurality of wiring sheets produced by the above-described method for manufacturing a wiring sheet. Can be easily manufactured.

  As shown in FIG. 1, the multilayer film 1 of the present invention has, for example, an adhesive resin layer 5 having a total reflectance of 16% or less, such as acrylate or methacrylate, for the ultraviolet ray, on a resin film 3 serving as a base material such as PET. The main adhesive resin layer 5 is formed by a doctor blade method or the like, and further, a photosensitive resin film 7 on the main surface of the adhesive resin layer 5, for example, in the case of a negative type, a dry film resist generally used is used. In the case of a positive type, it is a multilayer film 1 formed from a commonly used liquid resist by a spin coat method, a doctor blade method or the like. In addition, it is important that the total reflectance of the adhesive resin layer 5 with respect to light irradiated to the photosensitive resin film 7 such as i-line or h-line is 16% or less.

  Thereby, reflection of light from the adhesive resin layer 5 is suppressed, the resolution of the photosensitive resin film 7 is improved, and wiring with a line width of 30 μm or less can be easily formed.

  In general, the total reflectance is affected by the material, thickness, color, surface roughness, etc., but since the surface roughness of the adhesive resin layer is likely to change, the total reflectance of the adhesive resin layer 5 is controlled. It is desirable to control by changing the material and thickness of the adhesive resin layer 5.

  For example, an acrylic resin, particularly IBMA (isobutyl methacrylate) having a Tg of 60 ° C. or less can be suitably used as the adhesive resin layer 5. Further, the thickness of the adhesive resin layer 5 is desirably in the range of 0.8 to 7 μm from the viewpoint of handleability. When the thickness of the adhesive resin layer 5 is increased, the adhesiveness tends to increase.

  According to the present invention, it is important to impart adhesiveness to the adhesive resin layer 5 disposed between the resin film 3 and the photosensitive resin film 7, whereby the main surface of the adhesive resin layer 5 is photosensitive. When the negative photosensitive resin film 7 is used when the resin film 7 is formed and irradiated with ultraviolet rays, the adhesive resin is cured by the curing and crosslinking reaction of the photosensitive resin film 7 and the adhesiveness of the adhesive resin layer 5. Even if the reflectance of the layer 5 is low, the adhesive resin layer 5 and the photosensitive resin film 7 are firmly adhered, and the peeling of the photosensitive resin film 7 during development processing or the like can be suppressed. Therefore, the reflection of ultraviolet rays in the adhesive resin film 5 is suppressed, the resolution can be remarkably improved, and it is possible to form grooves and wirings with a line width of 30 μm or less and excellent in resolution. Compared with the conventional groove and wiring, the cross section is nearly rectangular, and it is easy to improve the wiring density. Similarly, in the case of a positive type, when a photosensitive resin film is formed on the resin film 3 by a spin coating method or the like, the adhesiveness between the adhesive resin layer 5 and the photosensitive resin film 7 is in a favorable range, The peeling of the photosensitive resin film 7 at the time of development processing or the like can be suppressed, and it is possible to form grooves and wirings having a line width of 30 μm or less and excellent resolution.

  The adhesive strength of the adhesive resin layer 5 used in the present invention is preferably in the range of 1 mN / mm to 15 mN / mm with respect to the photosensitive resin film 7, and the pattern of the photosensitive resin becomes PET by setting it to 1 mN / mm or more. By preventing the peeling from the resin film such as 15 mN / mm or less, the film can be peeled without load when the photosensitive resin film is finally peeled off.

  In particular, the range of 3 to 8 mN / mm is desirable because the balance between adhesiveness and peelability is good.

  The total reflectance of the adhesive resin layer 5 with respect to ultraviolet rays is preferably in a range of 0.05 to 16%, and by setting it to 0.05% or more, in the case of a negative type, undercut is suppressed, and a photosensitive resin. This pattern is prevented from peeling from a resin film such as PET. In the case of the positive type, since an appropriate amount of ultraviolet rays can be obtained by reflected light, it becomes possible to form grooves and wirings with excellent resolution.

  2 (a) and 2 (b), the grooved multilayer film 1a of the present invention has grooves 9 having a predetermined pattern formed on a part of the photosensitive resin film 7 of the multilayer film 1 of the present invention. The groove 9 preferably has a substantially rectangular cross section. Further, as shown in FIG. 2B, it is desirable that the width of the groove 9 is narrowed on the opening side, so that the photosensitive resin film 7 is removed after the wiring is formed in the groove 9 as will be described later. In this case, the photosensitive resin film 7 between the wirings can be easily removed.

  However, when the positive photosensitive resin film 7 is removed, the photosensitive resin film 7 is dissolved and removed using an alkaline solution. Therefore, as shown in FIG. The photosensitive resin film 7 can be easily removed even if the width is increased on the side.

  In particular, when the width 9a of the narrow portion of the groove 9 is set to 100 when the width 9b of the wide portion of the groove 9 is set to 100, the cross-sectional shape of the wiring becomes a substantially rectangular shape. It becomes a conductor excellent in resistance, S21 and the like.

  Then, in the groove 9 of the grooved multilayer film 1a of the present invention shown in FIGS. 2 (a), (b) and (c), as shown in FIGS. 3 (a), (b) and (c), a conductor paste By forming the conductor 13 in the groove 9 by filling, the multilayer film 15 with wiring of the present invention is obtained. In place of the conductor paste, a conductor may be formed in the groove 9 by plating.

  In addition, when a conductor paste is used, there exists an advantage that it can use easily also for preparation of not only a resin substrate but a ceramic substrate.

  According to the multilayer film 15 with wiring of the present invention, the wiring density can be improved and the cross-sectional shape of the wiring pattern is nearly rectangular compared to the screen printing method which is a wiring forming method in a conventional ceramic wiring board. Therefore, electrical characteristics such as specific resistance and high-frequency signal transmission loss (S21) are improved.

  Below, the manufacturing method of the multilayer film 1 of this invention, the multilayer film 1a with a groove | channel, and the multilayer film 15 with a wiring is demonstrated. In addition, a method for manufacturing a wiring sheet and a wiring board using the multilayer film 1, the grooved multilayer film 1a, and the multilayer film with wiring 15 will be described.

  First, as shown in FIG. 4 (a), a transparent and flexible resin film 3 such as a PET film is prepared. Next, as shown in FIG. 4 (b), a doctor blade method is applied to the main surface of the resin film 3. Is used to form the adhesive resin layer 5. The adhesive resin layer 5 is formed to have a thickness of 0.8 to 7 μm, for example, by a method such as doctor blade molding or spin coating.

  The adhesive resin layer 5 is preferably an acrylic resin, particularly, IBMA (isobutyl methacrylate) having a Tg of 60 ° C. or lower for imparting adhesiveness. The acrylic resin described above is used in an organic solvent such as toluene, IPA, or acetone. Examples of the forming method include a method such as doctor blade molding and spin coating after dissolution and liquefaction.

  Next, as shown in FIG. 4C, a photosensitive resin film 7 is formed on the main surface of the adhesive resin layer 5. When a negative photosensitive resin is used as the photosensitive resin film 7, a film-like dry film resist, which is the photosensitive resin film 7, is thermocompression bonded by a laminating machine, and the main surface of the adhesive resin layer 5 is photosensitive. A resin film 7 is formed. When a positive photosensitive resin is used, a liquid photosensitive resin dissolved in an organic solvent is formed on the main surface of the adhesive resin layer 5 by a spin coat method, a doctor blade method, or the like. A photosensitive resin film 7 is formed on the main surface 5.

  The photosensitive resin film 7 may be a so-called positive type, a negative type, or a negative type, and in any case, the multilayer film 1 is excellent in resolution.

  A desired pattern 19 corresponding to the wiring pattern formed on the transparent glass 17 is formed on the multilayer film 1 of the present invention shown in FIG. 1 and FIG. The exposed glass mask 21 is used to perform exposure processing using, for example, i-rays (365 nm) that are ultraviolet rays.

  Needless to say, the desired pattern of the glass mask 21 is reversed when the photosensitive resin film 7 is a negative type and a positive type.

  Next, for example, in the case of the negative type photosensitive resin film 7, development processing is performed with a 1% concentration sodium carbonate aqueous solution, and in the case of the positive type photosensitive resin film 7, a 0.7% concentration sodium hydroxide aqueous solution. Then, a development process is performed to form a groove 9 having a desired shape as shown in FIGS. 2A to 2C in the photosensitive resin film 7.

  In addition, by increasing / decreasing the amount of the ultraviolet rays irradiated at the time of exposure, the ultraviolet rays are attenuated on the adhesive resin layer 5 side, or the ultraviolet rays are reflected by the adhesive resin layer 5, and FIG. ), The width of the groove 9 can be reduced on the opening side, or the width of the groove 9 can be increased on the opening side as shown in FIG.

  By filling the formed groove 9 with a conductive paste containing metal powder, the wiring 13 as shown in FIGS. 3A to 3C can be formed.

  In addition, when the conductor paste is filled into the groove 9, first, an organic binder made of metal powder such as Cu powder or Ag powder and isobutyl methacrylate resin, and organic such as toluene, isopropyl alcohol, acetone, terpineol, etc. Conductor paste is prepared by mixing homogeneously with a solvent. Alternatively, a commercially available conductor paste may be used. The organic binder used is 0.5 to 5.0 parts by weight with respect to 100 parts by weight of the metal component, and the organic solvent is mixed at a ratio of 5 to 100 parts by weight with respect to 100 parts by weight of the solid component and the organic binder. It is desirable.

  In addition, you may add ceramic powder and glass powder to this conductor paste as needed. The produced conductor paste is embedded in the groove 9 formed in the photosensitive resin film 7 by a urethane rubber squeegee or a metal squeegee such as stainless steel. A squeegee is desirable because a sword squeegee is more easily embedded. Although the embedding method can be performed manually, it is more preferable to use a screen printer or the like in order to appropriately control the pressure.

  The wiring 13 may be formed by plating. In the case where the wiring 13 is formed by plating the groove 9, for example, a conductor (Cu etc.) layer 11 is formed on the entire surface of the photosensitive resin film 7 in which the groove 9 is formed by sputtering or the like. The photosensitive resin film is peeled 14 with an aqueous solution, and the conductor layer 11 is left only in the groove 9. Thereafter, the wiring 13 can be formed on the resin film by forming a Cu or Ag layer on the conductor layer 11 by wet plating.

  Thus, the multilayer film 15 with wiring of the present invention in which the wiring 13 is formed in the groove 9 can be produced.

  Further, by removing or dissolving the photosensitive resin film 7 from the multilayer film with wiring 15 using an aqueous alkali solution such as an aqueous sodium hydroxide solution, as shown in FIGS. The multilayer film 15 with wiring in which the photosensitive resin film 7 is removed on the main surface of the layer 5 and the exposed wiring 13 except for the bottom surface is disposed can be produced.

  When the wiring 13 of the multilayer film 17 with wiring thus prepared is used as a wiring board, for example, when a ceramic wiring board is manufactured, the photosensitive resin film 7 is removed as shown in FIG. A ceramic slurry 19 that is an insulator-containing slurry 19 containing ceramic powder is applied to the multilayer film 17 with wiring so as to cover the wiring 13 and the adhesive resin film 5 by a doctor blade method or the like, and further, As shown in FIG. 7B, after the ceramic slurry 19 is solidified to form an insulating sheet 22 that is a ceramic green sheet 22, the resin film 3 and the adhesive resin film 5 are peeled off, and the wiring 13 is embedded in the insulating sheet 22. Thus, the formed wiring sheet 23 can be obtained.

  Alternatively, as shown in FIG. 8 (a), the surface on which the wiring 13 of the multilayer film 17 with wiring from which the photosensitive resin film 7 is removed is opposed to the main surface of the ceramic green sheet 22 prepared in advance. Then, as shown in FIG. 8 (b), both are pressed and laminated by thermocompression by heating, and then, as shown in FIG. 8 (c), from this laminate, the resin film 3 and the adhesive resin film 5 is peeled off, and the wiring 13 is transferred to the ceramic green sheet, whereby the wiring sheet 23 formed by embedding the wiring 13 in the ceramic green sheet 22 as the insulating sheet 22 can be obtained.

  Then, as shown in FIG. 9A, a hole 25 is formed in a desired portion of the wiring sheet 23 using, for example, a laser beam, and the conductor paste is put in the hole 25 as shown in FIG. 9B. The vertical conductor 27 is formed by plating.

  Then, as shown in FIGS. 10A and 10B, a desired number of wiring sheets having vertical conductors 27 are stacked at desired positions, and this stacked body 29 is fired, so that the wiring substrate 31 A certain ceramic multilayer wiring board 31 can be obtained.

The ceramic green sheet 22 is a ceramic green sheet 22 formed by mixing, for example, crystallized glass or amorphous glass and an inorganic filler such as SiO ₂ , Al ₂ O ₃ , or ZrO ₂ , and a conventionally known material is used. Can do.

  Other examples of the inorganic filler include corundum (α alumina), forsterite, zirconia, and magnesia. Moreover, in the case of crystallized glass, the thing which precipitates crystal | crystallizations, such as quartz, cristobalite, cordierite, mullite, anorthite, serbian, spinel, garnite, willemite, dolomite, petalite, can be illustrated.

  Needless to say, a resin substrate 22 mainly composed of a resin may be used instead of the ceramic green sheet 22. As the insulator-containing slurry 19, a resin slurry 19 that becomes a resin substrate after solidification may be used instead of the ceramic slurry 19.

  First, an adhesive resin layer 5 mainly composed of IBMA (isobutyl methacrylate) and HEMA (hydroxyethyl methacrylate) was formed on the PET film and polyphenylene ether film used as the resin film 3 with the thickness shown in Table 1 by the doctor blade method. .

  Next, as the photosensitive resin film 7 having the thickness shown in Table 1 on the surface of the adhesive resin layer 5, a negative dry film resist (SPG102 = 10 μm thickness manufactured by Asahi Kasei Electronics, SPG202 = 20 μm thickness manufactured by Asahi Kasei Electronics, DuPont MRC) (Liston FRA305 made of dry film = 50 μm thickness) was thermocompression bonded with a laminator at a temperature of 90 ° C. and a pressure of 0.2 MPa. Further, the positive photosensitive resin film 7 was formed by forming a liquid photosensitive resin (PMER LA900PM manufactured by Tokyo Ohka Kogyo Co., Ltd.) on the surface of the adhesive resin layer 5 with the thickness shown in Table 1 using a doctor blade method.

Next, using a glass mask 21 on which a desired pattern is formed, UV (irradiation) with a wavelength of 365 nm is applied from the photosensitive resin film 7 side by a UV irradiator, in the case of a negative type, 100 mJ / cm ² , a positive type In this case, irradiation was performed at 500 mJ / cm ² . Further, in the case of the negative type, a 1 mass% sodium carbonate aqueous solution was used, and in the case of the positive type, a development process was carried out using a 0.7 mass% sodium hydroxide aqueous solution to form grooves 9 in the photosensitive resin film 7. .

  Next, 5 parts by weight of ethyl cellulose and 2.2.4 as an organic solvent with respect to 100 parts by weight of a mixed powder composed of 98% by weight of Cu or Ag powder having an average particle diameter of 2 μm and 2% by weight of borosilicate glass powder. -Trimethyl-3,3-pentadiol monoisobutyrate was added and mixed with a three roll mill to prepare a conductor paste, and this conductor paste was embedded in the groove 9 using a squeegee, and the multilayer film with wiring 17 of the present invention was used. Was made.

  Thereafter, the buried conductor paste was dried at a temperature of 80 ° C., and then the photosensitive resin film 7 was peeled off with a 2% NaOH aqueous solution. Next, a ceramic slurry prepared in advance is applied by a doctor blade method so as to cover the wiring 13 on the multilayer film 17 with wiring from which the photosensitive resin film 7 has been removed, and dried at 80 ° C., and then an adhesive resin layer By peeling the PET film 3 on which 5 was formed, a green sheet on which a wiring pattern was formed was produced.

The ceramic slurry used here was prepared by kneading 100 parts by weight of ceramic powder, 15 parts by weight of an organic binder (isobutyl methacrylate), and 70 parts by weight of toluene with a ball mill for 24 hours. Incidentally, the ceramic powder is a SiO ₂ as an inorganic filler, a non-crystalline borosilicate glass, an average particle diameter of the mixed raw material was used as the 2 [mu] m. As the glass composition, SiO ₂ : 40 wt%, B ₂ O ₃ : 10 wt%, BaO: 40 wt%, Al ₂ O ₃ : 5 wt%, and CaO: 5 wt% were used.

Next, a desired number of obtained green sheets with wiring were laminated and fired at a temperature of 950 ° C. to produce a ceramic wiring board. At this time, firing was performed in an N ₂ atmosphere in the case of a Cu conductor and in an Air atmosphere in the case of an Ag conductor.

  A multilayer film 17 with wiring was produced in the same manner as in Example 1. Thereafter, the buried conductor paste was dried at a temperature of 80 ° C., and then the photosensitive resin film 7 was peeled off with a 2% NaOH aqueous solution. Next, the photosensitive resin film 7 was removed, and a desired number of multilayer films 17 with wiring were produced.

  Next, as in Example 1, a ceramic slurry was prepared in advance. And this ceramic slurry was made into the green sheet by the doctor blade method. Next, the multilayer film with wiring produced previously was thermocompression bonded to the obtained green sheet surface at a temperature of 20 MPa and 80 ° C. to produce a green sheet on which a wiring pattern was formed. Thereafter, a ceramic wiring board was produced in the same manner as in Example 1.

  (Multilayer film evaluation: reflectance measurement) The reflectance after forming the adhesive resin layer and the release layer on the resin film alone and the resin film was measured. Measurement was performed at a wavelength of 365 nm using a Minolta spectrocolorimeter.

  (Multilayer film evaluation: adhesive strength measurement) An adhesive resin layer was formed on a resin film, and a negative photosensitive resin film having a thickness shown in Table 1 on the surface of the adhesive resin layer was subjected to thermocompression bonding at 90 ° C. and 0.2 MPa. A 180 ° peel test using an autograph apparatus was performed. In addition, the positive type photosensitive resin film is formed by applying a liquid resist: PMER LA900PM manufactured by Tokyo Ohka Kogyo Co., Ltd. to the surface of the adhesive resin layer using a doctor blade method to have the thickness shown in Table 1, and a 180 ° peel test using an autograph device Went. In this 180 ° peel test, the multilayer film was cut into a size of 15 mm wide × 100 mm long, pulled at a speed of 300 mm / min, and the load when the photosensitive resin film completely peeled was read. The strength is shown in Table 1.

  Moreover, when there was no adhesive resin layer which is a comparative example, after forming the photosensitive resin film directly on the surface of the resin film which is a base material, the same evaluation as the case where the adhesive resin layer was provided was performed.

  Moreover, when there was no adhesive resin layer as a comparative example and a release layer was provided instead, the same evaluation was performed on the photosensitive resin film provided on the surface of the release layer.

  (Multilayer film evaluation: photosensitive resin film pattern peeling, pattern width dimension evaluation) The multilayer film formed with the obtained grooves was observed with a 20-fold optical microscope to confirm that the photosensitive resin film pattern was not peeled off. did. The width dimension of the photosensitive resin film pattern was measured with a 100 times microscope, and NG was measured when the dimension of the narrow portion was less than 95%.

  (Evaluation of multilayer film with wiring: pattern disconnection) A mask of lines / spaces (L / S = 20/20 μm, L / S = 30/30 μm, L / S = 50/50 μm) shown in Table 1 is formed on the glass mask 21. Then, a wiring pattern was formed, and the pattern in which the pattern was disconnected or short-circuited was defined as NG. The width of the groove and the wiring on the opening side coincided with the line of the glass mask.

These test results are shown in Table 1. In addition, since the result was the same in Example 1 and 2, only the result of Example 1 was described in Table 1.

  From Table 1, the sample using the multilayer film of the present invention maintains a high resolution of the photosensitive resin film, and can form a wiring pattern with a cross section of 30 μm or less, which is close to a rectangle, and between the photosensitive resin film and the resin film. A multi-layer film with grooves and a multi-layer film with wiring for producing a wiring pattern of a wiring board suitable for a mobile communication device with good adhesion and a package for housing a semiconductor element were obtained.

  Further, when the reflection of the adhesive resin layer increases, the difference between the width of the narrow portion of the groove and the width of the widest portion on the bottom side of the groove tends to increase.

  On the other hand, among the samples outside the scope of the present invention, sample No. 1 using polyphenylene ether as the resin film and having no adhesive resin layer was used. No. 1, although the total reflectance of the adhesive resin layer is as low as 0.02%, the photosensitive resin film peels off during the development process, and a groove cannot be formed in the photosensitive resin film. It was. In addition, PET as a resin film and a sample No. having no adhesive resin layer. In No. 2, the photosensitive resin film was not peeled off by the development treatment, but the cross section of the groove and the wiring pattern was greatly deviated from the rectangle.

  In addition, among samples using a positive type photosensitive resin film, the sample No. of the present invention in which the groove is wide on the opening side. In 28-31, 35, 36, 39, and 40, the conductor paste could be filled easily.

  Note that sample No. In Nos. 24 and 25, the positive type liquid photosensitive resin could not be satisfactorily formed on the resin film due to bleeding or repellency. For this reason, the adhesive strength could not be measured.

  In addition, sample No. outside the scope of the present invention. In Nos. 41 to 43, the adhesive strength of the photosensitive resin film is very low and peeling easily occurs. In 41, the tendency was remarkable.

It is sectional drawing of the multilayer film of this invention. It is sectional drawing of the multilayer film with a groove | channel of this invention. It is sectional drawing of the multilayer film with a wiring of this invention. It is sectional drawing explaining the manufacturing method of the multilayer film with wiring of this invention. It is sectional drawing explaining the manufacturing method of the multilayer film with a groove | channel of this invention. It is sectional drawing explaining the manufacturing method of the wiring sheet of this invention. It is sectional drawing explaining the manufacturing method of the wiring sheet of this invention. It is sectional drawing explaining the manufacturing method of the wiring sheet of this invention. It is sectional drawing explaining the manufacturing method of the wiring board of this invention. It is sectional drawing explaining the manufacturing method of the wiring board of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Multi-layer film 1a ... Multi-layer film 3 with a groove | channel ... Resin film 5 ... Adhesive resin layer 7 ... Photosensitive resin film 9 ... Groove 13 ... Wiring 15 ... Multi-layer film with wiring 22 ... insulating sheet, ceramic green sheet 23 ... wiring sheet 31 ... wiring board, ceramic multilayer wiring board

Claims (12)

A multilayer film, wherein an adhesive resin layer having a total reflectance of 16% or less with respect to ultraviolet rays is formed on a main surface of a resin film, and a photosensitive resin film is formed on the main surface of the adhesive resin layer. The multilayer film according to claim 1, wherein the photosensitive resin film has a thickness of 10 to 50 μm. A grooved multilayer film, wherein grooves are formed in the photosensitive resin film of the multilayer film according to claim 1. The grooved multilayer film according to claim 3, wherein a width of the groove is narrower on an opening side in a depth direction. 4. The grooved multilayer film according to claim 3, wherein the photosensitive resin film is a positive photosensitive resin film, and the width of the groove is wider on the opening side in the depth direction. 6. The grooved multilayer film according to claim 4, wherein the width of the narrow portion of the groove is 95 or more, where 100 is the width of the widest portion of the groove. A multilayer film with wiring, wherein a conductor is formed in the groove of the grooved multilayer film according to claim 3 to form a wiring. The multilayer film with wiring according to claim 7, wherein the conductor is a conductor paste. Forming an adhesive resin layer having a total reflectance of 16% or less on the main surface of the resin film, forming a photosensitive resin film on the main surface of the adhesive resin layer, and preparing a multilayer film; Irradiating the photosensitive resin film with light corresponding to a desired wiring pattern; developing the photosensitive resin film; removing a part of the photosensitive resin film; and The manufacturing method of the multilayer film with wiring characterized by comprising the process of forming a groove | channel in a resin film, and the process of forming a conductor in the said groove | channel, and forming wiring. The process of removing the said photosensitive resin film from the multilayer film with a wiring produced by the manufacturing method of the multilayer film with a wiring of Claim 9, and the said wiring of the multilayer film with a wiring which removed the said photosensitive resin film formed A step of laminating the main surface of the insulating sheet on the main surface of the laminated side to produce a laminate, and a step of removing the resin film and the adhesive resin layer from the laminate. A method for manufacturing a wiring sheet. An insulator is provided so as to cover the wiring and the adhesive resin layer by removing the photosensitive resin film from the multilayer film with wiring produced by the method for producing a multilayer film with wiring according to claim 9. A step of applying an insulator-containing slurry, a step of solidifying the insulator-containing slurry to form an insulating sheet, and a laminate in which the wiring is embedded; and the resin film and the adhesive from the laminate And a step of removing the resin layer. A method for manufacturing a wiring board, comprising a step of laminating a plurality of the wiring sheets produced by the method for manufacturing a wiring sheet according to claim 10 or 11.

Images