JP2008118105A - Ion gun treatment method, copper clad laminate manufactured by using the same method, and printed circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ion gun treatment method for preventing a sample from being damaged by fire. <P>SOLUTION: This ion gun treatment method is characterized to carry out ion gun treatment to a sample in such a state that an insulator and the sample to which the ion gun treatment is carried out are arranged in this order on a sample stand. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ion gun processing method, and a copper-clad laminate and a printed wiring board manufactured using the same.

  In recent years, there has been an increasing demand for electronic devices that are smaller, lighter, and faster, and the density of printed wiring boards and flexible printed wiring boards has been increasing. Therefore, in addition to the wet process conventionally used in this field, studies are being made to use a dry process used in the field of semiconductors for a method of manufacturing a printed wiring board or a flexible printed wiring board.

One of the dry processes being studied is ion gun treatment. Ion gun treatment has begun to be applied to pretreatment for improving the adhesion between the organic insulating layer and the wiring. For example, in order to improve the adhesion between the organic resin layer and the wiring, a technique for forming a wiring layer after performing ion gun treatment on the surface of the organic resin layer is known (for example, see Patent Document 1). Also, a technique for improving the adhesion between the wiring and the organic resin layer formed thereon by performing ion gun processing (ion beam processing) on the wiring surface after the wiring is formed is known (for example, see Patent Document 2). Yes.
International Publication No. 2004/050352 Pamphlet Japanese Patent No. 2792413

  However, when an ion gun treatment is performed on the sample, the potential of the charged sample increases, and the potential difference between the surrounding metal or the metal part in the sample increases, so that the potential difference exceeds the withstand voltage of the sample, and the sample There may be a problem that dielectric breakdown occurs and a part of the sample is burned out. This problem is particularly noticeable when the sample stage is made of metal or when metal is exposed on a part of the sample stage surface, and when there are vias, through holes, metal layers, wirings, etc. on the sample surface. Was more prominent.

  In addition, the thickness of a sample (substrate, organic insulating layer, etc.) subjected to ion gun processing tends to be thinner year by year, and accordingly, the possibility of causing dielectric breakdown during ion gun processing is increasing year by year. As an example, Kapton 100EN (trade name, manufactured by Toray DuPont Co., Ltd.), which is a polyimide film having a thickness of 25 μm, is placed on a metal sample stage, and first a metal layer (Cr layer having a thickness of about 5 nm). ) Is formed using a sputtering method, and then 300W ion gun treatment is applied for about 180 seconds in order to improve the adhesion between the polyimide film and the metal layer, dielectric breakdown occurs between the metal layer and the sample stage. The sample was burned out.

  Accordingly, an object of the present invention is to solve the above-described problem, that is, to provide an ion gun processing method in which a sample does not burn out. Another object of the present invention is to provide a copper-clad laminate and a printed wiring board that do not burn.

That is, the present invention relates to an ion gun processing method characterized in that an ion gun treatment is performed on a sample stage in a state where an insulator and a sample to be subjected to ion gun processing are arranged in this order. The ion gun processing method of the present invention can be preferably applied to a sample in which an insulating material is exposed in at least a part of a portion in contact with an insulator. Alternatively, the ion gun processing method of the present invention uses a sample stage in which metal is exposed on at least a part of the surface on which the sample is arranged, or a sample stage in which metal is exposed on the entire surface on which the sample is arranged. In this case, it can be preferably applied.
Moreover, this invention relates to the copper clad laminated board produced using the said ion gun processing method.
Furthermore, this invention relates to the printed wiring board produced using the said ion gun processing method, or the printed wiring board produced using the said copper clad laminated board.

  According to the present invention, it is possible to prevent sample burnout by interposing an insulator between the sample stage and the sample in the ion gun treatment. As a result, it is possible to manufacture a good copper-clad laminate and printed wiring board without burning.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The ion gun processing method of the present invention is an ion gun processing method characterized in that an ion gun treatment is performed on a sample stage in a state where an insulator and a sample to be subjected to the ion gun processing are arranged in this order.

(Ion gun treatment)
In the ion gun treatment, positive or negative charged ions are extracted from plasma generated in an ion generation chamber, accelerated, and irradiated on a sample. As the irradiation method, there are a method of irradiating charged ions linearly and a method of irradiating in a planar manner, and a method of irradiating in a planar manner is preferable from the viewpoint of productivity. Compared with the plasma treatment, the ion gun treatment has an advantage that the kinetic energy of charged ions can be easily controlled by the acceleration voltage.

  In principle, the ion gun treatment method can be performed even under atmospheric pressure, but generally, the kinetic energy of charged ions is significantly reduced by the presence of molecules in the atmosphere. Has not been put to practical use. Therefore, the present invention is preferably applied to ion gun processing in a vacuum.

A gas used for the ion gun treatment is not particularly limited, and examples thereof include a rare gas (for example, Ar), a nitrogen-based gas, a fluorine-based gas, a chlorine-based gas, and an oxygen-based gas (for example, O ₂ ).

  When processing a sample having a metal material such as a via, a through hole, a metal layer, or a wiring on the sample surface (surface to be subjected to ion gun processing), it is desirable to use a rare gas when it is desired to suppress metal oxidation. . The rare gas includes He, Ne, Ar, Kr, Xe, Rn, etc., but it is desirable to use Ar for practical use.

(Insulator)
An insulator is a substance having a large electric resistance value, and preferably a substance having a breaking voltage of 3 kV or more. The insulator is not particularly limited as long as it is a substance having a large electric resistance value, and examples thereof include an organic insulating base material, a ceramic base material, and a glass base material. For example, polyimide, polyamide, epoxy resin, or polyethylene terephthalate can be used as the organic insulating substrate. The thickness of the insulator is preferably a thickness that does not cause dielectric breakdown by ion gun treatment. The thickness at which dielectric breakdown does not occur is not only affected by the material and thickness of the sample subjected to the ion gun treatment, but also by the material of the insulator used, the energy of the ion gun treatment, the gas used, etc. For this reason, it is preferable to determine the thickness beforehand through experiments or the like. For example, a sample to be subjected to ion gun treatment is a polyimide film (for example, Kapton 100EN (trade name, manufactured by Toray DuPont Co., Ltd.)), and a polyimide film (for example, Kapton V (manufactured by Toray DuPont Co., Ltd .; Name)), argon gas is used as the gas, and the irradiation condition is 0.5 kW, the thickness of the insulator is preferably 25 μm or more. In consideration of handleability, it is inconvenient if it is too thick, and is preferably 200 μm or less.

  A film-like thing can also be used as an insulator. The film-like insulator can be attached to the back surface of the sample (surface in contact with the insulator) using an adhesive or the like, and is effective for preventing scratches on the back surface of the sample. However, when an insulator that can be attached is used, it is preferable that the insulator does not remain on the sample when it is peeled off from the sample.

(Sample stage)
A sample to be subjected to an insulator and an ion gun treatment is placed on the sample stage. The shape and thickness of the sample stage are not particularly limited.

  A sample stage to which the present invention is preferably applied is a metal sample stage, a sample stage in which metal is exposed on the entire surface on which the sample is placed, or at least part of the face on which the sample is placed. It is a sample stage. This is because in these cases, the sample causes dielectric breakdown at the portion in contact with the sample base metal, and the sample is easily burnt.

(sample)
The sample to which the present invention can be preferably applied is a sample having an insulating material at least in a part thereof, for example, a sample in which an insulating material is exposed in at least a part of a part in contact with the insulator of the sample, or the whole A sample made of an insulating material. This is because if such a sample is placed directly on the sample stage without interposing an insulator, the sample is likely to break down and easily burn out. This problem is remarkable in a sample having a layer made of a thin insulating material. Since the ion gun treatment method of the present invention can prevent such burning due to dielectric breakdown, it is particularly effective for a sample having a layer made of a thin insulating material.

  Examples of the sample include a material or an intermediate for manufacturing a copper clad laminate, a material or an intermediate for manufacturing a printed wiring board, and the like. Although the manufacturing method of a copper clad laminated board and a printed wiring board is demonstrated later, as these materials, a resin layer (insulating material) is normally used. By using the ion gun treatment method of the present invention, a copper-clad laminate or a printed wiring board can be produced without causing burnout due to dielectric breakdown even with a thin resin layer. The ion gun treatment method of the present invention can be preferably applied to the production of COF (chip on film) having a thin resin layer in addition to the conventional copper clad laminate and printed wiring board.

  In addition, the ion gun treatment method of the present invention can be preferably applied to a sample having vias, through holes, metal layers, wirings, or resin layers, particularly to a sample having these on the surface to which the ion gun is applied.

(Copper-clad laminate and printed wiring board)
The copper-clad laminate and the printed wiring board of the present invention can be manufactured as follows.

(Copper-clad laminate manufacturing method)
The manufacturing method of the copper clad laminated board of this invention has the process of forming a copper layer on both surfaces or one side of a resin layer. Furthermore, you may have the process of forming an adhesion metal layer and a seed layer (thin metal layer) between the resin layer and the copper layer. The ion gun treatment can be applied to a resin layer, an adhesive metal layer, a seed layer, a copper layer, or the like. The adhesive metal layer is a thin metal layer provided between both layers in order to improve the adhesive force between the resin layer and the copper layer.

(Printed wiring board manufacturing method)
The manufacturing method of the printed wiring board of this invention has the process of forming wiring in the both surfaces or single side | surface of a resin layer. As a method for forming the wiring, a metal layer (copper layer, adhesive metal layer, seed layer, etc.) is formed on the resin layer, and unnecessary portions of the metal layer are removed by etching (subtract method). A method of forming a wiring by plating only at a necessary place (additive method), a method of forming a seed layer on a resin layer, and then forming a necessary wiring by electrolytic plating and then removing the seed layer by etching (Semi-additive method). The ion gun treatment can be applied to a resin layer, a metal layer, a resin layer on which wiring is formed, and the like. The ion gun treatment method of the present invention is particularly effective for the wiring formation method by the subtractive method and the semi-additive method.

(Resin layer)
As the resin layer of the copper clad laminate and the printed wiring board of the present invention, a thermosetting insulating material, a thermoplastic insulating material, or a mixed insulating material thereof can be used. Thermosetting insulating materials include phenol resin, urea resin, melamine resin, alkyd resin, acrylic resin, unsaturated polyester resin, diallyl phthalate resin, epoxy resin, silicone resin, resin synthesized from cyclopentadiene, tris (2- Resin containing hydroxyethyl) isocyanurate, resin synthesized from aromatic nitrile, trimerized aromatic dicyanamide resin, resin containing triallyl trimethacrylate, furan resin, ketone resin, xylene resin, heat containing condensed polycyclic aromatics A curable resin, a benzocyclobutene resin, a norbornene resin, or the like can be used. Examples of the thermoplastic insulating material include polyimide resin, polyphenylene oxide resin, polyphenylene sulfide resin, aramid resin, and liquid crystal polymer. A filler may be added to the insulating material. Examples of the filler include silica, talc, aluminum hydroxide, aluminum borate, aluminum nitride, and alumina.

  The thickness of the resin layer can be appropriately set according to the intended copper-clad laminate and printed wiring board. Although it does not specifically limit about an upper limit, For example, from viewpoints, such as handleability and economical efficiency, Preferably it is 200 micrometers or less, More preferably, it is 100 micrometers or less, More preferably, it is 50 micrometers or less. Since the ion gun treatment method of the present invention is particularly effective for thin samples, the lower limit is not limited. For example, the resin layer is preferably 5 μm or more from the viewpoint of handleability.

(Via)
In the printed wiring board, vias (via holes) for electrically connecting the wirings of the respective layers can be provided. The via can be formed by providing a hole for connection in the resin layer and filling the hole with a conductive paste or plating. Examples of the hole processing method include mechanical processing such as punching and drilling, laser processing, chemical etching processing using chemicals, and dry etching processing using plasma.

(Through hole)
In the printed wiring board, through holes can be provided to electrically connect the layers. The through hole can be formed by providing a hole for connection in the resin layer and electrically connecting the hole with a conductive paste or plating. Examples of the hole processing method include mechanical processing such as punching and drilling, laser processing, chemical etching processing using chemicals, and dry etching processing using plasma.

(Metal layer)
For the metal layer, it is preferable to use a metal that improves the adhesion between the wiring and the resin layer. As the metal, for example, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Zr, Mo, Pd, W, Cu, etc. can be used, and two or more of these metals are used in combination. You can also A plurality of metal layers may be formed. When producing a copper clad laminate, at least Cu is used.

(Metal layer formation method)
Methods for forming a metal layer on a resin layer include a method of forming using a dry process such as sputtering, ion plating, cluster ion beam, or chemical vapor deposition (CVD), and plating. There is a method of forming using a wet type process. For example, when the metal layer is formed by sputtering, the sputtering apparatus used may be multipolar sputtering such as bipolar sputtering or tripolar sputtering, magnetron sputtering, RF sputtering, mirrortron sputtering, reactive sputtering, or the like. it can.

  A method of forming a metal layer in a vacuum such as sputtering tends to have a slow formation rate of the metal layer. Therefore, after depositing a thin metal layer in a vacuum by sputtering or the like to form a seed layer, a method of further thickening the metal using electroplating may be used.

  In order to improve the adhesion between the metal layer and the resin layer, the surface of the resin layer can be pretreated before the metal layer is formed. Examples of the pretreatment include dry treatment such as ion gun treatment, and wet treatment using an acid or an alkali solution. The ion gun processing method of the present invention is particularly effective for dry processing.

  In order to improve the adhesion between the metal layer and the resin layer, an ion gun treatment can be performed after the metal layer is formed thin (adhesive metal layer). In this case, the thickness of the adhesive metal layer is preferably in the range of 0.1 nm to 100 nm because the adhesive force between the adhesive metal layer and the resin layer is improved, more preferably 0.1 nm to 10 nm, and particularly 1 nm to 100 nm. The range of 8 nm is preferable because the adhesive force between the adhesive metal layer and the resin layer is most improved. When the thickness of the adhesive metal layer exceeds 100 nm, the adhesive force between the adhesive metal layer and the resin layer tends to decrease. On the other hand, when the thickness is less than 0.1 nm, the insulation resistance value between wirings to be formed later tends to decrease. Since the thickness of the adhesive metal layer is affected by ion gun processing conditions and the like, it is preferable to obtain an optimum thickness in advance through experiments or the like.

  The thickness of the entire metal layer can be appropriately set according to the intended copper-clad laminate and printed wiring board. As an example, the thickness is preferably 0.5 to 70 μm, more preferably 1 to 36 μm, still more preferably. It can be 3-18 micrometers.

(Wiring formation by subtract method (etching))
A metal layer is formed on the resin layer, an etching resist is formed at a portion that becomes a wiring of the metal layer, and a chemical etching solution is sprayed and sprayed on a portion exposed from the etching resist to remove an unnecessary metal layer by etching. Thus, a wiring can be formed. For example, when using a copper layer as a metal layer, the etching resist material which can be used for a normal wiring board can be used for an etching resist. For example, an etching resist is formed by silk-screen printing of a resist ink to form an etching resist, or a negative photosensitive dry film for an etching resist is laminated on a copper layer, and light is applied in a wiring shape thereon. Is formed by overlapping a photomask that passes through, exposing with ultraviolet light, and removing the unexposed portion with a developer.

(Wiring formation by additive (plating))
Further, the wiring can be formed only by performing plating only on a necessary portion on the resin layer, and a wiring forming technique by normal plating can be used. For example, after the treatment method of the present invention is applied to the resin layer, the electroless plating catalyst is adhered to the resin layer. After that, a plating resist is formed on the surface portion where the resin layer is not plated, the resin layer is immersed in an electroless plating solution, and electroless plating is performed only on the portion not covered with the plating resist, and wiring is performed. Form.

(Wiring formation by semi-additive method)
In the wiring formation method by the semi-additive method, a seed layer is formed, a plating resist is formed thereon in a necessary pattern, and wiring is formed by electrolytic copper plating through the seed layer. Thereafter, the plating resist is peeled off, and finally the seed layer is removed by etching or the like to form a wiring.

(Semi-additive seed layer formation method)
In the electroplating process in the semi-additive method, the seed layer is usually formed to a thickness that allows current to flow. The method of forming the seed layer of the semi-additive method on the resin layer includes methods such as vapor deposition, sputtering, ion plating, cluster ion beam, chemical vapor deposition (CVD), plating, and bonding metal foil. is there. A subtractive metal layer can also be formed by the same method. The present invention is a particularly effective means for forming a seed layer by vapor deposition, sputtering, ion plating, cluster ion beam, or chemical vapor deposition.

  For example, when an adhesive metal layer and a thin film copper layer are formed by sputtering as a seed layer, sputtering devices used include multipolar sputtering such as bipolar sputtering and tripolar sputtering, magnetron sputtering, RF sputtering, and mirrortron sputtering. , Reactive sputtering or the like can be used. The target used for sputtering is preferably, for example, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Zr, Mo, Pd, W, Cu, or an alloy thereof in order to ensure adhesion. . Using these targets, one or two or more adhesive metal layers are sputtered so that the total thickness becomes 0.1 to 100 nm. Thereafter, sputtering is performed using copper as a target so that the thickness of the thin film copper layer becomes 100 to 500 nm.

  Also, a plated copper layer having a thickness of 0.5 to 3 μm can be formed as a seed layer on the resin layer by electroless copper plating.

  When the resin layer has an adhesive function, the seed layer can also be formed by bonding metal foils by pressing or laminating. However, it is very difficult to directly bond a thin metal foil, so a method of thinning a metal foil with a carrier layer after laminating a metal foil with a carrier layer after laminating a thick metal foil and so on. For example, as the former, there is a three-layer copper foil of carrier copper / nickel / thin film copper, and carrier copper may be removed with an alkaline etching solution and nickel with a nickel etching solution. As the latter, a peelable copper foil using aluminum, copper, an insulating film or the like as a carrier can be used, and a seed layer of 5 μm or less can be formed. Alternatively, a 9 to 18 μm thick copper foil may be attached and the seed layer may be formed by etching to a uniform thickness so as to be 5 μm or less.

(Specific example of a method for producing a copper clad laminate)
The copper clad laminate using the present invention can be manufactured by the following steps. 1A to 1F are schematic cross-sectional views showing an example of an embodiment of a method for producing a copper-clad laminate in the present invention. However, the order of the manufacturing process is not particularly limited as long as it does not depart from the object of the present invention.

(Process a)
(Step a) is a step of disposing the resin layer 100 on the insulator 101 as shown in FIG. In order to dispose the resin layer on the insulator without slipping, it is preferable to attach the resin layer to the insulator. A method for attaching is not particularly limited, but a method of attaching an end portion of the resin layer 100 to the insulator 101 with an adhesive tape, a method of attaching the resin layer 100 to the insulator 101 using an adhesive, a pressure bonding method, or the like. There is a method in which the resin layer 100 is attached to the insulator 101. Note that the insulator 101 is preferably formed using a material that can be removed from the resin layer 100 by a method such as an etching method or a peeling method.

(Process b)
(Step b) is a step of forming the metal layer 102 on the resin layer 100 as shown in FIG. The metal layer 102 is formed on the resin layer 100 by using a dry process such as sputtering, ion plating, cluster ion beam, or chemical vapor deposition (CVD), plating, or the like. There is a method using a wet type process.

  For example, when the metal layer is formed by sputtering, multipolar sputtering such as bipolar sputtering or tripolar sputtering, magnetron sputtering, RF sputtering, mirrortron sputtering, reactive sputtering, or the like can be used as a sputtering apparatus.

(Process c)
(Step c) is a step of performing ion gun treatment as shown in FIG. In step c, the resin layer 100 (sample) formed by bonding the insulator 101 to the metal sample stage 103 not covered with the insulator in the ion gun processing apparatus to form the adhesive metal layer 102 is insulated. This is a step of placing the body 101 in contact with the sample stage 103 and subjecting the sample to ion gun treatment. After the ion gun treatment, the sample is taken out from the apparatus.

(Process d)
(Step d) is a step of removing the insulator 101 from the resin layer 100 as shown in FIG. Since the removal method is affected by the pasted method, it is preferable to determine the method and conditions in advance by experiments or the like. For example, when it is attached by lamination using a releasable adhesive, it can be removed by a method of peeling by hand or a method of winding each separately.

(Process e)
(Step e) is a step of forming a copper layer 104 on the adhesive metal layer 102 as shown in FIG. For example, after forming a copper thin film by sputtering, vapor deposition, electroless plating, or the like, the copper layer 104 is obtained by copper plating to a desired thickness using electrolytic copper plating.

(Process f)
By repeating (step a) to (step e), the adhesive metal is similarly applied to the other surface of the resin layer (the surface opposite to the surface on which the copper layer is formed) as shown in FIG. Layer 102 and copper layer 104 can be formed. Thereby, a double-sided copper clad laminated board can be manufactured.

  In (Step f), the insulator is disposed between the copper layer 104 formed in (Step e) and the sample stage.

  FIGS. 1A to 1F show an example in which the adhesive metal layer 102 is subjected to ion gun treatment after the adhesive metal layer 102 is formed. However, after the resin layer 100 is subjected to ion gun treatment, the adhesive metal layer 102 is subjected to ion gun treatment. May be formed. In that case, the method for forming the adhesive metal layer 102 may be the same as the method shown in (Step b). In addition, an arbitrary metal layer (not shown) may be formed on the adhesive metal layer 102 after the ion gun treatment is performed on the adhesive metal layer 102 in (Step c).

(Specific example of printed wiring board manufacturing method)
A printed wiring board using the present invention can be manufactured by the following steps. 2 (g) to (l) are schematic cross-sectional views showing a method for producing a printed wiring board in which wiring is formed on one side as an example of an embodiment of a method for manufacturing a printed wiring board in the present invention. However, the order of the manufacturing process is not particularly limited as long as it does not depart from the object of the present invention.

(Process g)
(Step g) is a step of disposing the resin layer 200 on the insulator 201 as shown in FIG. The arrangement method may be the same as the method shown in (Step a).

(Process h)
(Step h) is a step of forming the adhesive metal layer 202 on the resin layer 200 as shown in FIG. The method for forming the adhesive metal layer 202 may be the same as the method shown in (Step b).

(Process i)
(Step i) is a step of performing ion gun treatment as shown in FIG. In (step i), a resin layer 200 (sample) in which an insulator 201 is attached to a metal sample stage 203 in an ion gun processing apparatus to form an adhesive metal layer 202 is used. In this step, the sample is placed in contact with 203 and subjected to ion gun treatment. After the ion gun treatment, the sample is taken out from the apparatus.

(Process j)
(Step j) is a step of removing the insulator 201 from the resin layer 200 as shown in FIG. The removal method may be the same as the method shown in (Step d).

(Process k)
(Step k) is a step of forming the copper layer 204 on the adhesive metal layer 202 as shown in FIG. The method for forming the copper layer may be the same as in (Step e).

(Process l)
(Step l) is a step of forming the wiring 205 as shown in FIG. As a method for forming the wiring, first, a resist is formed in a pattern on the copper layer 204, and unnecessary portions of the copper layer 204 and the adhesive metal layer 202 are removed using an etching method. By this method, the wiring 205 is obtained.

  FIGS. 2G to 2L show an example in which an ion gun process is performed on the adhesive metal layer after the adhesive metal layer 202 is formed. However, after the ion gun process is performed on the resin layer 200, the adhesive metal layer 102 is formed. May be formed. In that case, the method for forming the adhesive metal layer 202 may be the same as the method shown in (Step b). In addition, an arbitrary metal layer (not shown) may be formed on the adhesive metal layer 202 after the ion gun treatment is performed on the adhesive metal layer 202 in (Step i).

  An embodiment of the present invention will be described with reference to FIGS. In the embodiment, the resin layer 100 in FIG. 1 will be described as a polyimide resin layer 100, the insulator 101 as a polyimide insulator 101, and the adhesive metal layer 102 as a Cr layer 102. In FIG. 2, the resin layer 200 will be described as a polyimide resin layer. 200, the insulator 201 is the polyimide insulator 201, and the adhesive metal layer 202 is the Cr layer 202, but the present invention is not limited to this.

(Example 1)
(Process a)
As shown in FIG. 1A, a polyimide film (thickness 25 μm, area 20 cm □, Upilex-25S (trade name, manufactured by Ube Industries, Ltd.)) (hereinafter also referred to as a polyimide resin layer) as the resin layer 100. Is prepared, and a polyimide film (thickness 125 μm, area 25 cm □, Upilex-125S (trade name, manufactured by Ube Industries, Ltd.)) (hereinafter also referred to as polyimide insulator) is pasted as an insulator 101 on one side. It was. The polyimide resin layer 100 is attached using a polyimide tape with an acrylic pressure-sensitive adhesive layer (thickness 75 μm, polyimide pressure-sensitive adhesive tape, No. 360 series (manufactured by Nitto Denko Corporation, trade name)) (not shown). These four corners were attached to the polyimide insulator 101.
When the polyimide resin layer 100 was attached to the polyimide insulator 101, the polyimide resin layer 100 was attached so that no wrinkles were generated.

(Process b)
As shown in FIG.1 (b), the polyimide resin layer 100 affixed on the polyimide insulator 101 was arrange | positioned on the sample stand 103 (product made from SUS301) in a sputtering device. At that time, the polyimide insulator 101 was in contact with the sample stage 103. A Cr layer (thickness: 5 nm) was formed as the adhesive metal layer 102 on the surface of the polyimide resin layer 100 using a sputtering method. Sputtering was performed under the condition 1 shown below using a load lock type sputtering apparatus model SIH-350-T08 (trade name, manufactured by ULVAC, Inc.).
Condition 1
Power: 500W
Argon flow rate: 100 SCCM
Degree of vacuum: 7.0 × 10 ⁻¹ Pa
Temperature: Room temperature (25 ° C)
Deposition rate: 34 nm / min

(Process c)
As shown in FIG. 1C, ion gun treatment was performed on the sample surface (the surface of the Cr layer 102 formed on the polyimide resin layer 100). Specifically, the ion gun treatment is performed under condition 2 by placing the sample on the sample stage 103 in the same apparatus without removing it from the vacuumed apparatus after forming the Cr layer 102 in (step b). It was. At this time, the sample stage 103 was not covered with an insulator. As the ion gun processing apparatus, an ion gun processing apparatus linear ion source (manufactured by Advanced Energy, trade name) attached to a load lock type sputtering apparatus model SIH-350-T08 (trade name, manufactured by ULVAC, Inc.) was used.
Condition 2
Power: 500W
Argon flow rate: 100 SCCM
Degree of vacuum: 7.0 × 10 ⁻¹ Pa
Temperature: Room temperature (25 ° C)
Processing time: 60 seconds

Further, a Cr layer (not shown) (thickness 5 nm) is formed in the same apparatus on the surface of the Cr layer 102 that has been subjected to the ion gun treatment without removing the sample from the vacuumed apparatus. A layer (not shown) (thickness 200 nm) was formed. The Cr layer was formed under the same conditions as in Condition 1, and the Cu thin film layer was formed under Condition 3.
Condition 3
Power: 500W
Argon flow rate: 100 SCCM
Degree of vacuum: 7.0 × 10 ⁻¹ Pa
Temperature: Room temperature (25 ° C)
Deposition rate: 52 nm / min

(Process d)
Next, as shown in FIG. 1D, after the sample was taken out of the sputtering apparatus, the polyimide tape (not shown) was peeled off, and the polyimide insulator 101 was removed from the polyimide resin layer 100.

(Process e)
Thereafter, a copper layer 104 (thickness 8 μm) was formed by electroplating using the Cr layer and the Cu thin film layer formed in (Step b) and (Step c) as seed layers.

(Process f)
Then, the double-sided copper clad laminated board was produced by repeating the process similar to (process a)-(process e) on the surface in which the copper layer 104 of a polyimide resin layer is not formed. That is, after forming the adhesion metal layer 102, an ion gun treatment was performed, a Cr layer and a Cu thin film layer were formed as seed layers, and a copper layer 104 (thickness 8 μm) was formed by electroplating.

(Example 2)
In (Step b), (Step c) and (Step f) of (Example 1), a Ni layer was formed in place of the Cr layer. The thickness of the Ni layer was the same as that of the Cr layer of (Example 1). The Ni layer was formed under the condition 4 below. Other steps were the same as in Example 1 to produce a double-sided copper-clad laminate.
Condition 4
Power: 500W
Argon flow rate: 100 SCCM
Degree of vacuum: 7.0 × 10 ⁻¹ Pa
Temperature: Room temperature (25 ° C)
Deposition rate: 29 nm / min

(Example 3)
In Example 1, the resin layer 100 is replaced with Upilex-25S (trade name, manufactured by Ube Industries), and Kapton 100EN (manufactured by Toray DuPont Co., Ltd.), which is a polyimide film having a thickness of 25 μm. Name). Other processes were the same as in Example 1, and a double-sided copper-clad laminate was produced.

Example 4
In Example 2, Kapton 100EN (trade name, manufactured by Toray DuPont Co., Ltd.), which is a polyimide film having a thickness of 25 μm, was used as the resin layer 100 instead of Upilex-25S. Other processes were the same as in (Example 2), and a double-sided copper-clad laminate was produced.

(Example 5)
(Process g)
As shown in FIG. 2G, a polyimide film (thickness 25 μm, area 20 cm □, Upilex-25S (trade name, manufactured by Ube Industries, Ltd.)) (hereinafter also referred to as polyimide resin layer) is used as the resin layer 200. Was prepared, and a polyimide film (thickness 125 μm, 25 cm □, Upilex-125S (manufactured by Ube Industries, Ltd., trade name)) as an insulator 201 was attached to one surface thereof. Affixing is performed by affixing the four corners of the polyimide resin layer 200 to the polyimide insulator 201 using a polyimide tape (thickness 75 μm, NITTO TAPE (trade name, manufactured by Nitto Denko Corporation)) (not shown). went.
Note that when the polyimide resin layer 200 was attached to the polyimide insulator 201, the polyimide resin layer 200 was attached so that wrinkles would not occur.

(Process h)
As shown in FIG. 2 (h), the polyimide resin layer 200 attached to the polyimide insulator 201 was placed on a sample stage 203 (made of SUS301) in the sputtering apparatus. At that time, the polyimide insulator 201 was in contact with the sample stage 203. A Cr layer (5 nm) was formed as the adhesive metal layer 202 on the surface of the polyimide resin layer 200 by sputtering. Sputtering was performed under condition 1 using a load lock type sputtering apparatus model SIH-350-T08 (trade name, manufactured by ULVAC, Inc.).

(Process i)
As shown in FIG. 2I, an ion gun treatment was performed on the sample surface (the surface of the Cr layer 202 formed on the polyimide resin layer 200). Specifically, the ion gun treatment is performed under the condition 2 by placing the sample on the sample stage 203 in the same apparatus without removing it from the vacuumed apparatus after forming the Cr layer 202 in (step h). It was. At this time, the sample stage 203 was not covered with an insulator. As an ion gun processing apparatus, an ion gun processing apparatus linear ion source (manufactured by Advanced Energy, trade name) attached to a load lock type sputtering apparatus model SIH-350-T08 (trade name, manufactured by ULVAC, Inc.) was used.

  Further, a Cr layer (not shown) (thickness: 5 nm) is formed in the same apparatus on the surface of the Cr layer 202 that has been subjected to the ion gun treatment without taking out the sample from the vacuumed apparatus, and further a Cu thin film. A layer (not shown) (thickness 200 nm) was formed. The Cr layer was formed under the same conditions as in Condition 1, and the Cu thin film layer was formed under Condition 3.

(Process j)
Next, as shown in FIG. 2 (j), after the sample was taken out of the sputtering apparatus, the polyimide tape (not shown) was peeled off, and the polyimide insulator 201 was removed from the polyimide resin layer 200.

(Process k)
Thereafter, a copper layer 204 (thickness 8 μm) was formed by electroplating using the Cr layer and the Cu thin film layer formed in (Step h) and (Step i) as seed layers.

(Process l)
After a resist is formed on the copper layer 204 and exposed in a pattern, the Cu layer, the Cu thin film layer, and the Cr layer are removed using an etching solution by using a subtractive method, whereby the wiring 205 is formed. Formed. A ferric chloride etching solution was used as the etching solution for the Cu layer and the Cu thin film layer, and a potassium ferricyanide etching solution was used as the etching solution for the Cr layer. In this way, a printed wiring board was produced.

(Example 6)
In (Step h) and (Step i) of (Example 5), a Ni layer was formed in place of the Cr layer. The thickness of the Ni layer was the same as that of the Cr layer of (Example 5). The Ni layer was formed under the same condition as condition 4. Other processes were the same as in (Example 5) to produce a printed wiring board.

(Example 7)
In Example 5, the resin layer 200 is replaced with Upilex-25S (trade name) manufactured by Ube Industries, Ltd., and Kapton 100EN (manufactured by Toray DuPont Co., Ltd.), which is a polyimide film having a thickness of 25 μm. Name). Other steps were the same as in (Example 5), and a printed wiring board was produced.

(Example 8)
In Example 6, as the resin layer 200, Kupton 100EN (trade name, manufactured by Toray DuPont Co., Ltd.), which is a polyimide film having a thickness of 25 μm, was used instead of Upilex-25S. Other steps were the same as in (Example 6) to produce a printed wiring board.

(Comparative Example 1)
(Step a) and (Step d) in (Example 1) and (Step a) and (Step d) in (Step f) were not performed. Otherwise, the same process as in Example 1 was used to produce a double-sided copper-clad laminate.

(Comparative Example 2)
(Step a) and (Step d) in (Example 2) and (Step a) and (Step d) in (Step f) were not performed. Otherwise, a double-sided copper-clad laminate was produced using the same steps as in Example 2.

(Comparative Example 3)
(Step a) and (Step d) in (Example 3) and (Step a) and (Step d) in (Step f) were not performed. Otherwise, a double-sided copper-clad laminate was prepared using the same steps as in Example 3.

(Comparative Example 4)
(Step a) and (Step d) in (Example 4) and (Step a) and (Step d) in (Step f) were not performed. Otherwise, a double-sided copper-clad laminate was produced using the same steps as in Example 4.

(Comparative Example 5)
(Step g) and (Step j) of (Example 5) were not performed. Otherwise, a printed wiring board was produced using the same steps as in Example 5.

(Comparative Example 6)
(Step g) and (Step j) of (Example 6) were not performed. Otherwise, a printed wiring board was produced using the same steps as in Example 6.

(Comparative Example 7)
(Step g) and (Step j) of (Example 7) were not performed. Otherwise, a printed wiring board was produced using the same steps as in Example 7.

(Comparative Example 8)
(Step g) and (Step j) of (Example 8) were not performed. Otherwise, a printed wiring board was fabricated using the same steps as in (Example 8).

  The external appearance was observed about the double-sided copper clad laminated board produced in the above Examples 1-4 and Comparative Examples 1-4. Similarly, the external appearance was observed about the printed wiring board produced in Examples 5-8 and Comparative Examples 5-8. The appearance was visually determined and examined for the presence of burnout due to dielectric breakdown. Twenty-five samples were prepared for each sample, and the samples with burnout were regarded as defective. Table 1 shows the number of defective samples.

  In the case of the double-sided copper clad laminate produced in Examples 1 to 4 and the printed wiring board produced in Examples 5 to 8 using the ion gun treatment method of the present invention, the sample was not burned out due to dielectric breakdown. On the other hand, in the case of the double-sided copper clad laminate produced in Comparative Examples 1 to 4 and the printed wiring board produced in Comparative Examples 5 to 8 without using the ion gun treatment method of the present invention, dielectric breakdown was observed in most samples. Burnout was observed.

(A)-(f) is process drawing which shows one Embodiment of the manufacturing method of the copper clad laminated board of this invention. (G)-(l) is process drawing which shows one Embodiment of the manufacturing method of the printed wiring board of this invention.

Explanation of symbols

100, 200 Resin layer 101, 201 Insulator 102, 202 Adhesive metal layer 103, 203 Sample stage (metal not covered with insulator)
104, 204 Electroplated copper layer (copper layer)
105, 205 wiring

Claims (10)

  An ion gun processing method, wherein an ion gun treatment is performed on a sample stage in a state where an insulator and a sample to be subjected to an ion gun treatment are arranged in this order.   The ion gun processing method according to claim 1, wherein an insulating material is exposed on at least a part of a portion of the sample that contacts the insulator.   The ion gun processing method according to claim 1, wherein a metal is exposed on at least a part of a surface of the sample stage on which the sample is arranged.   The ion gun processing method according to claim 1, wherein the metal is exposed on the entire surface of the sample stage on which the sample is arranged.   The ion gun processing method according to claim 1, wherein the ion gun processing is performed in a vacuum.   The ion gun processing method according to claim 1, wherein a gas used for the ion gun processing is a rare gas.   The ion gun treatment method according to any one of claims 1 to 6, wherein the sample to be subjected to the ion gun treatment has any one or more selected from the group consisting of vias, through holes, metal layers, wirings, and resin layers.   The copper clad laminated board produced using the ion gun processing method in any one of Claims 1-7.   The printed wiring board produced using the ion gun processing method in any one of Claims 1-7.   A printed wiring board produced using the copper clad laminate according to claim 8.

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