JP4480111B2 - Wiring forming method and wiring member - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wiring forming method and a wiring member, and more particularly to a wiring forming method for forming wiring on a polyimide layer and a wiring member in which wiring is formed by the wiring forming method.
[0002]
[Prior art]
Due to dramatic progress in semiconductor technology, semiconductor packages are becoming smaller, more pins, and fine pitches.
Furthermore, the market trend of electronic parts has been rapidly miniaturized and thinned, and has entered the era of so-called high-density packaging.
In such circumstances, a wiring member for an interposer for mounting a semiconductor element on a printed circuit board, a wiring member for forming a semiconductor device, or other semiconductor peripheral member is capable of fine wiring and has an electrical property aspect. However, an excellent wiring member is required.
[0003]
As a method for forming a wiring pattern, there are mainly a subtractive method and an additive method. In general, a metal layer (copper foil) for forming a metal wiring portion is formed on the entire surface of an insulating substrate. The method of forming a wiring part by removing a predetermined region of the metal layer by etching or the like is called a subtractive method, and the metal wiring part formed by plating or the like is directly or indirectly added to an insulating substrate. This method is called the additive method.
In the subtractive method, a wiring layer is usually formed by etching a metal layer (copper foil) affixed to an insulating substrate, which is technically complete and inexpensive, but the thickness of the metal layer There is a problem that it is difficult to finely process the wiring part due to the limitations of the thickness, etc. The additive method forms the metal wiring part by plating, so the wiring part can be miniaturized, but it is difficult in terms of cost reliability. is there.
[0004]
The subtractive method has a problem of side etching. To form a fine pattern, an insulating layer is formed on the base substrate, or the base substrate is an insulating layer, and the wiring layer is formed on the insulating layer by the additive method. The wiring formation method to form is taken.
As a method for forming an insulating layer on a base substrate, a so-called printing method such as screen printing is widely used for mass production, and optical exposure is performed using a photosensitive resin for forming a high-density, high-precision pattern. A developing method (photolithographic method) is commonly used.
As the insulating layer, in particular, a polyimide layer is widely used in terms of its insulating properties and chemical mechanical stability.
[0005]
A wiring forming method in which an insulating layer is formed on a base substrate, or a base substrate is used as an insulating layer, and a wiring layer is formed on the insulating layer by an additive method is usually an electroless plating layer first on the insulating layer. A power supply layer is formed, a resist layer having an opening corresponding to the shape of the wiring is formed thereon, and selective plating is performed by electrolytic plating in order to form the wiring layer.
Conventionally, as an electroless plating layer, an electroless nickel plating layer has been formed by electroless nickel plating from the viewpoint of adhesion to polyimide.
However, the electroless nickel plating layer has a problem that the film resistance is high and an oxide film on the nickel surface is formed.
[0006]
[Problems to be solved by the invention]
As described above, in the additive wiring method in which the electroless nickel plating layer is formed on the insulating layer as the power feeding layer, and the wiring layer is selectively formed on the insulating layer by electrolytic plating, the electroless nickel plating layer is a film. This is required because the resistance is high and an oxide film is formed on the nickel surface.
The present invention corresponds to these, and in particular, in a wiring formation method by an additive method in which a power feeding layer is formed on an insulating layer made of a polyimide layer, and a wiring layer is selectively formed by electrolytic plating thereon, It is an object of the present invention to provide a wiring forming method capable of forming a wiring having good adhesion using a power feeding layer that can reduce the resistance and does not form an oxide film on the surface of an electroless nickel plating layer as in the prior art.
At the same time, the present invention intends to provide a wiring member in which wiring is formed by such a wiring forming method.
[0007]
[Means for Solving the Problems]
  The wiring forming method of the present invention is a method of forming wiring on a polyimide layer, and in order, (a) a surface on which a polyimide layer wiring is formed is formed in a roughened state. And (b) a feed layer forming step of providing a feed layer for electrolytic plating a main layer for forming a wiring on the roughened surface of the polyimide layer, and (c) electrolysis on the feed layer. A resist layer forming step of forming a resist layer having an opening corresponding to a wiring to be selectively plated by plating; (d) a wiring layer forming step of electrolytically forming a main layer for forming a wiring on the power feeding layer; ) After removing the resist layer, a cleaning process is performed if necessary, and a soft etching process is performed to remove the exposed power feeding layer by soft etching so as not to damage the wiring. Plating After a catalyst is applied and electroless nickel plating is performed to form an electroless nickel plating layer, the resistivity reducing metal layer is a metal layer on the electroless nickel plating layer to reduce the resistance of the power feeding layer. That formThen, the formation of the metal layer for reducing the resistivity is performed in the order of electroless nickel plating and electrolytic copper plating in succession to electroless nickel plating, and in order, on the electroless nickel plating layer, electrolytic nickel plating layer and electrolytic copper plating. Is to form a layerIt is characterized by this.
  Alternatively, the wiring forming method of the present invention isA method of forming wiring on a polyimide layer, in which (a) a surface for forming wiring of a polyimide layer is formed in a roughened state, and (b) a polyimide layer. A power feeding layer forming step of providing a power feeding layer for electrolytic plating formation of a main layer for forming a wiring on the roughened surface, and (c) wiring for selective plating formation by electrolytic plating on the power feeding layer. A resist layer forming step for forming a resist layer having a combined opening, (d) a wiring layer forming step for electrolytically forming a main layer for forming wiring on the power feeding layer, and (e) necessary after removing the resist layer And a soft etching process for removing the exposed power feeding layer by soft etching so as not to damage the wiring. The power feeding layer forming process imparts a catalyst for electroless plating and Electrolysis After forming the electroless nickel plating layer by performing Kel plating, a metal layer for reducing the resistivity, which is a metal layer for reducing the resistance of the power feeding layer, is formed on the electroless nickel plating layer. The formation of the metal layer for decreasing the resistivity is characterized in that nickel strike plating, electrolytic nickel plating, and electrolytic copper plating are sequentially performed following electroless nickel plating.
  And aboveAny wiring formation method,The roughening polyimide layer forming step is characterized by forming a rough surface by a wet blast method.
  And also aboveAny wiring formation method,The roughening polyimide layer forming step is characterized in that the metal foil of the laminated material in which the polyimide layer is formed on the rough surface of the metal foil is removed by etching, and the surface exposed by etching is roughened. To do.
[0008]
The wiring member of the present invention is a wiring member in which wiring is formed on a polyimide layer (including an electrodeposited polyimide layer), and the wiring is formed by the above-described wiring forming method. Is.
[0009]
[Action]
  In the wiring forming method of the present invention, the wiring forming method according to the additive method, in which the power supply layer is formed on the insulating layer made of the polyimide layer and the wiring layer is selectively formed by electrolytic plating on the insulating layer made of the polyimide layer. Therefore, it is possible to provide a wiring forming method capable of forming a wiring with good adhesion using a power feeding layer in which an oxide film is not formed on the surface of an electroless nickel plating layer as in the prior art. .
  Specifically, it is a method of forming a wiring on a polyimide layer, and in order, (a) a surface for forming a wiring of a polyimide layer is formed in a roughened state, a roughened polyimide layer forming step, (B) a power feeding layer forming step of providing a power feeding layer for electrolytic plating the main layer forming the wiring on the roughened surface of the polyimide layer; and (c) selection by electrolytic plating on the power feeding layer. A resist layer forming step for forming a resist layer having an opening corresponding to the wiring to be plated; (d) a wiring layer forming step for electrolytically forming a main layer for forming a wiring on the power feeding layer; and (e) a resist layer. After removing the electrode, a cleaning process or the like is performed as necessary, and a soft etching process is performed to remove the exposed power feeding layer by soft etching so as not to damage the wiring. The power feeding layer forming process is a catalyst for electroless plating. Grant After forming an electroless nickel plating layer by performing electroless nickel plating, a metal layer for reducing resistivity, which is a metal layer for reducing the resistance of the power feeding layer, is further formed on the electroless nickel plating layer InThen, the formation of the metal layer for reducing the resistivity is performed in the order of electroless nickel plating and electrolytic copper plating in succession to electroless nickel plating, and in order, on the electroless nickel plating layer, electrolytic nickel plating layer and electrolytic copper plating. Is to form a layerOrA method of forming wiring on a polyimide layer, in which (a) a surface for forming wiring of a polyimide layer is formed in a roughened state, and (b) a polyimide layer. A power feeding layer forming step of providing a power feeding layer for electrolytic plating formation of a main layer for forming a wiring on the roughened surface, and (c) wiring for selective plating formation by electrolytic plating on the power feeding layer. A resist layer forming step for forming a resist layer having a combined opening, (d) a wiring layer forming step for electrolytically forming a main layer for forming wiring on the power feeding layer, and (e) necessary after removing the resist layer And a soft etching process for removing the exposed power feeding layer by soft etching so as not to damage the wiring. The power feeding layer forming process imparts a catalyst for electroless plating and Electrolysis After forming the electroless nickel plating layer by performing Kel plating, a metal layer for reducing the resistivity, which is a metal layer for reducing the resistance of the power feeding layer, is formed on the electroless nickel plating layer. The formation of the resistivity lowering metal layer is to perform nickel strike plating, electrolytic nickel plating, and electrolytic copper plating in order following electroless nickel plating.This has been achieved.
[0010]
Here,Following the electroless nickel plating, the formation of the metal layer for decreasing the resistivity is performed by electrolytic nickel plating and electrolytic copper plating in order, and on the electroless nickel plating layer, the electrolytic nickel plating layer and the electrolytic copper plating layer are formed in order. Or the formation of the resistivity lowering metal layer is to sequentially perform nickel strike plating, electrolytic nickel plating, and electrolytic copper plating after electroless nickel plating.More power supplyThe film resistance of the layer is reduced, the surface of the electroless nickel plating layer is prevented from being oxidized, and the subsequent electroplating can be performed without forming the surface of the power feeding layer.
  As a result, the electrolytic plating property and / or the adhesion of the wiring can be improved.
[0011]
Also, the roughened polyimide layer forming step forms a rough surface by a wet blast method, or the metal foil of the laminated material in which the polyimide layer is formed on the rough surface of the metal foil is removed by etching. By making the surface exposed by etching rough, it is possible to roughen the polyimide layer surface with a desired roughness, thereby forming the electroless nickel layer of the power feeding layer, and thus the entire power feeding layer. The wiring can be formed on the polyimide layer with good adhesion.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
An example of an embodiment of the present invention will be described.
FIG. 1 is a process cross-sectional view of an example of an embodiment of a wiring forming method of the present invention, and FIG. 2 is a partially enlarged cross-sectional view of FIG. FIG.
1 and 2, 110 is a polyimide layer, 120 and 125 are copper foils, 130 is a power feeding layer, 131 is an electroless nickel plating layer, 132 is an electroless copper plating layer, 133 is an electrolytic nickel plating layer, and 134 is an electrolysis A copper plating layer, 135 is a strike nickel plating layer, 136 is a strike copper plating layer, 140 is a resist layer, and 150 is an electrolytic plating layer.
[0013]
An example of an embodiment of the wiring forming method of the present invention will be described with reference to FIG.
The wiring formation method of this example is a method of forming a wiring mainly composed of an electrolytic copper plating layer on the exposed surface of the polyimide layer 110 of the copper foil laminated material obtained by laminating the copper foil on one surface of the polyimide layer. is there.
First, a double-sided copper foil laminate (FIG. 1 (a)) in which a copper foil is laminated on both sides of a polyimide layer is prepared, the copper foil on one side is removed by etching, and a copper foil laminate in which a copper foil is laminated on one side of the polyimide layer. Get the material. (Fig. 1 (b))
In addition, after adjusting the roughness of the polyimide layer 110 side of the copper foil 125 on the etching side to a predetermined value in advance, a double-sided copper foil laminate is formed by thermocompression bonding, or such a commercially available double-sided laminate is used. Use materials.
As the roughness of the surface on the polyimide layer 110 side of the copper foil 125 to be removed by etching of the double-sided copper foil laminate, one that can stably perform electroless plating and wiring formation described later with good adhesion is selected.
As the roughness, those having a center line average roughness Ra in the range of 0.1 μm to 0.5 μm are preferable.
[0014]
  Next, a power supply layer 130 for performing electrolytic plating for wiring formation described later is formed. (Fig. 1 (c))
  The formation of the power feeding layer will be described with reference to FIG.
  First Method for Forming Feed Layer 130(First reference method)As follows, after applying a catalyst such as Pd to the polyimide layer 110 and activating it, applying a predetermined electroless nickel plating to form the electroless nickel plating layer 131, and then continuing the electroless copper plating thereon There is a method in which the electroless copper plating layer 132 is formed and the electroless nickel plating layer 131 and the electroless copper plating layer 132 are combined to form a power feeding layer. (Fig. 2 (a), Fig. 2 (b))
  Second method of forming power supply layer 130(First method of the embodiment of the present invention)As follows, after applying a catalyst such as Pd to the polyimide layer 110 and activating it, applying a predetermined electroless nickel plating to form an electroless nickel plating layer 131, and then successively electrolytic nickel plating, There is a method in which electrolytic copper plating is performed to form an electrolytic nickel plating layer 133 and an electrolytic copper plating layer 134, and the electroless nickel plating layer 131, the electrolytic nickel plating layer 133, and the electrolytic copper plating layer 134 are combined to form a power feeding layer. (Fig. 2 (a), Fig. 2 (c))
  Third method of forming the power feeding layer 130(Second method of the embodiment of the present invention)As follows, after applying a catalyst such as Pd to the polyimide layer 110 and activating it, applying a predetermined electroless nickel plating to form the electroless nickel plating layer 131, and then successively forming the strike nickel plating Electrolytic nickel plating and electrolytic copper plating are performed to form a strike nickel plating layer 135, an electrolytic nickel plating layer 133, and an electrolytic copper plating layer 134, an electroless nickel plating layer 131, a strike nickel plating layer 135, and an electrolytic nickel plating layer 133. There is a method in which the electrolytic copper plating layer 134 is combined into a power feeding layer. (Fig. 2 (a), Fig. 2 (d))
  Fourth Method for Forming Feed Layer 130(Second reference method)As follows, after applying a catalyst such as Pd to the polyimide layer 110 and activating it, applying a predetermined electroless nickel plating to form the electroless nickel plating layer 131, and subsequently performing a strike copper plating thereon There is a method in which a strike copper plating layer 136 is formed and the electroless nickel plating layer 131 and the strike copper plating layer 136 are combined to form a power feeding layer. (Fig. 2 (a), Fig. 2 (e))
  Electroless plating methods such as electroless nickel plating are well known and will not be described here. In the power supply layer 130 formed by the first to fourth methods, a portion other than the electroless nickel layer is referred to as a resistivity reducing metal layer.
[0015]
Next, a resist layer 140 having an opening corresponding to a wiring to be selectively plated by electrolytic plating is formed on the power supply layer 130 by photolithography. (Fig. 1 (d))
The resist is not particularly limited as long as it has plating resistance, a predetermined resolution, and good processability.
Next, the main layer for forming the wiring is formed on the power feeding layer exposed from the opening of the resist layer by electrolytic plating. (Fig. 1 (e))
The main layer of the wiring formed by electrolytic plating is usually a copper plating layer from the viewpoint of conductivity and cost, but other plating layer single layer, such as gold plating layer, silver plating layer, nickel plating layer, or The plating layer including a copper plating layer may be formed in multiple layers.
A known method can be applied to the electrolytic plating such as electrolytic plating copper plating.
[0016]
Next, after removing the resist layer 140, a cleaning process or the like is performed as necessary (FIG. 1F), and the exposed power feeding layer 130 is removed by soft etching so as not to damage the wiring. (Fig. 1 (g))
Soft etching is performed with a predetermined etching solution corresponding to the layer structure of the power feeding layer 130.
Thereby, the wiring composed of the power feeding layer 130 and the electrolytic plating layer 140 is formed on the polyimide layer.
[0017]
As a modified example of this example, a base layer made of a copper foil or other member is formed by casting, extruding, or electrodepositing a polyimide layer, or a polyimide film is formed through an adhesive layer. Using a material or a substrate made of polyimide film, the polyimide layer is roughened to a predetermined roughness by wet blasting, and then a wiring layer is formed on the polyimide layer (or polyimide film) in the same manner as in this example. A wiring formation method can be mentioned.
The polyimide electrodeposition liquid for electrodeposition formation of the polyimide layer is based on the description in JP-B-51-15051, the description in JP-B-46-17415, and the description in JP-A-9-104839. Can be obtained.
By combining these described methods, it is also possible to synthesize a carboxylic acid-containing polyimide having an imide bond and an amic acid, which is produced as a result of charging and synthesizing an aromatic tetracarboxylic acid aromatic diamine component. Furthermore, in addition to the aromatic tetracarboxylic acid and the aromatic diamine component, a carboxylic acid-containing monomer is charged in advance during synthesis, and finally a polyimide varnish containing an imide bond, an amic acid, and a carboxylic acid functional group can be synthesized.
In order to obtain an electrodeposition solution, a base such as an amine is added to this varnish, a part of the imide bond is further opened to form a neutralized salt, and water and various solvents are added as necessary. Thus, an electrodeposition solution of polyimide can be produced.
[0018]
【Example】
  (Reference Example 1)
  Reference Example 11 is a method for forming the first power feeding layer 130 in the embodiment shown in FIG.(First reference method)The power feeding layer is formed by the above, and the electrolytic plating layer 150 for forming the wiring is only the electrolytic copper plating layer.
  First, as a double-sided copper foil laminate in which copper foil is laminated on both sides of a polyimide layer, commercially available Espanox (manufactured by Nippon Steel Chemical Co., Ltd., SB18-25-18uE) is prepared (FIG. 1 (a)). The copper foil 125 on one side was removed by etching with a ferric chloride solution to obtain a copper foil laminate in which the copper foil 120 was laminated only on one side of the polyimide layer. (Fig. 1 (b))
  The roughness of the exposed surface of the polyimide layer 110 was about Ra = 0.5 μm.
[0019]
Next, catalyst application and electroless nickel plating were performed under the following conditions to form an electroless plating layer 131 with a thickness of 0.5 μm. (Fig. 2 (a))
<Electroless nickel plating>
Sensitizing; S-10X (Uemura Kogyo) 3 minutes
Activating; A-10X (Uemura Kogyo) 3 minutes
Electroless plating; NPR-4 (made by Uemura Kogyo) 1 minute
[0020]
Subsequent to electroless nickel plating, the electroless copper plating layer 132 is formed to a thickness of 0.1 μm by dipping in an electroless copper plating solution (20 ° C.) having the following composition made by Shipley East Co., Ltd. for 20 minutes. (Fig. 2 (b))
<Electroless copper plating>
Cue deposit 328A 120ml / l
Cue deposit 328L 110ml / l
Cue deposit 328C 10ml / l
Pure water 760ml / l
Thereby, the power feeding layer 130 composed of the electroless plating layer 131 and the electroless copper plating layer 132 was formed. (Fig. 2 (b))
The sheet resistance of the power feeding layer 130 was 0.4Ω.
[0021]
Next, a resist PMER-AR900 manufactured by Tokyo Ohka Kogyo Co., Ltd. is applied and formed on the power supply layer 130 to a thickness of 15 μm (after pre-baking) using a spin coater, and exposure and development are performed. After the formation (not shown), electrolytic copper plating is performed on the power supply layer 130 exposed from the opening under the following conditions, and a main layer of wiring made of an electrolytic plating layer (electrolytic copper plating layer) 150 having a thickness of 10 μm. Formed. (Fig. 1 (e))
The development was performed by immersing and shaking for 3 minutes in a predetermined developer (manufactured by Tokyo Ohka Kogyo, P-6G).
<Electrolytic copper plating>
Copper sulfate (pentahydrate) 70g / l
Sulfuric acid 200g / l
Hydrochloric acid 0.5ml / l
Spur Throw 2000 Brightener 10ml / l
Spur Throw 2000 Correction Agent 5ml / l
Temperature 20 ° C
Current density 4A / dm²
15 minutes
[0022]
Next, after the resist is peeled off with acetone (FIG. 1 (f)), the electroless copper plating layer 132 is exposed to AD485 (manufactured by Meltex Co., Ltd.) among the power feeding layer 130 exposed so as not to damage the wiring portion. Then, the electroless nickel plating layer 131 was removed by soft etching so as not to impair the wiring part at the Nimden lip C-11. (Fig. 1 (g))
Further, in order to remove the catalyst, a wet blast processing apparatus manufactured by Macau Corporation was used. Alumina abrasive # 1000 (average particle size 11.5 μm), abrasive concentration 20%, pump pressure 0.5 kg / cm²The wet blast treatment was performed under the condition of a treatment speed of 10 m / min.
In this way, a wiring layer having a width of 15 μm was formed on the polyimide layer 110, but the wiring was formed uniformly.
[0023]
  Example 1
  Example 1Is a method of forming the second power supply layer 130 in the embodiment shown in FIG.(First method of the embodiment of the present invention)The power supply layer is formed by the above, and the electrolytic plating layer 150 for forming the wiring is only the electrolytic copper plating layer.Reference Example 1Only the fabrication of the power feeding layer 130 isReference exampleUnlike other processes,Reference Example 1In this manner, a wiring member is formed.
  Hereinafter, only the formation of the power feeding layer 130 will be described.
  Reference Example 1In the same manner as above, the application of catalyst and electroless nickel plating were performed to form an electroless plating layer 131 with a thickness of 0.5 μm (FIG. 2A). Electrolytic nickel plating and electrolytic copper plating were performed in order on the following conditions, using 131 as a power feeding layer, and an electrolytic nickel plating layer 133 and an electrolytic copper plating layer 134 were formed to a thickness of 1 μm and 0.8 μm, respectively. (Fig. 2 (c))
  <Electrolytic nickel plating>
      Nickel sulfate (hexahydrate) 300g / l
      Nickel chloride (hexahydrate) 45g / l
      Boric acid 40g / l
      PC nickel A-1 10ml / l
                        A-2 1ml / l
              Temperature 50 ℃
              Current density 1A / dm2
              1 minute
  <Electrolytic copper plating>
      Copper sulfate (pentahydrate) 70g / l
      Sulfuric acid 200g / l
      Hydrochloric acid 0.5ml / l
      Spur Throw 2000 Brightener 10ml / l
      Spur Throw 2000 Correction Agent 5ml / l
              Temperature 20 ° C
              Current density 4A / dm2
              1 minute
  Thereby, the power feeding layer 130 including the electroless plating layer 131, the electrolytic nickel layer 133, and the electrolytic copper plating layer 134 was formed. (Fig. 2 (c))
  The sheet resistance of the power feeding layer 130 was 0.8Ω.
  Also in this example, a wiring layer having a width of 15 μm was formed on the polyimide layer 110, but the wiring was formed uniformly.
[0024]
  (Example 2)
  Example 2Is a method of forming the third power feeding layer 130 in the embodiment shown in FIG.(Second method of the embodiment of the present invention)The power supply layer is formed by the above, and the electrolytic plating layer 150 for forming the wiring is only the electrolytic copper plating layer.Reference Example 1Only the fabrication of the power feeding layer 130 isReference exampleUnlike other processes,Reference Example 1In this manner, a wiring member is formed.
  Hereinafter, only the formation of the power feeding layer 130 will be described.
  Reference Example 1In the same manner as above, the application of catalyst and electroless nickel plating were performed to form an electroless plating layer 131 with a thickness of 0.5 μm (FIG. 2A). 131 is used as a power feeding layer, and strike nickel plating, electrolytic nickel plating, and electrolytic copper plating are performed in order on the following conditions, and the strike nickel plating layer 135, the electrolytic nickel plating layer 133, and the electrolytic copper plating layer 134 are respectively formed. The thickness was 1 μm, 1 μm, and 0.8 μm. (Fig. 2 (c))
  <Strike nickel plating>
      Nickel chloride (hexahydrate) 250g / l
      Hydrochloric acid 125ml / l
      Temperature
      Current density 10A / dm2
      2 minutes
  <Electrolytic nickel plating>
      Nickel sulfate (hexahydrate) 300g / l
      Nickel chloride (hexahydrate) 45g / l
      Boric acid 40g / l
      PC nickel A-1 10ml / l
                        A-2 1ml / l
      Temperature 50 ℃
      Current density 1A / dm2
      1 minute
  <Electrolytic copper plating>
      Copper sulfate (pentahydrate) 70g / l
      Sulfuric acid 200g / l
      Hydrochloric acid 0.5ml / l
      Spur Throw 2000 Brightener 10ml / l
      Spur Throw 2000 Correction Agent 5ml / l
      Temperature 20 ° C
      Current density 4A / dm2
      1 minute
  As a result, a power feeding layer 130 including the electroless plating layer 131, the strike nickel plating layer 135, the electrolytic nickel layer 133, and the electrolytic copper plating layer 134 was formed.
(Fig. 2 (d))
  The sheet resistance of the power feeding layer 130 was 0.4Ω.
  Also in this example, a wiring layer having a width of 15 μm was formed on the polyimide layer 110, but the wiring was formed uniformly.
[0025]
  (Reference Example 2)
  Reference Example 2Is a method of forming the fourth power feeding layer 130 in the embodiment shown in FIG.(Second reference method)The power supply layer is formed by the above, and the electrolytic plating layer 150 for forming the wiring is only the electrolytic copper plating layer.Reference Example 1Only the fabrication of the power feeding layer 130 isReference exampleUnlike other processes,Reference Example 1In this manner, a wiring member is formed. Hereinafter, only the formation of the power feeding layer 130 will be described.
  Reference Example 1In the same manner as above, the application of catalyst and electroless nickel plating were performed to form an electroless plating layer 131 with a thickness of 0.5 μm (FIG. 2A). Using 131 as a power feeding layer, strike copper plating was performed under the following conditions to form a strike copper plating layer 136 having a thickness of 1 μm (or ridge). (Fig. 2 (c))
  <Strike copper plating>
      Cuprous cyanide 25g / l
      Sodium cyanide 50g / l
      Sodium carbonate 30g / l
      Free sodium cyanide 7g / l
      Rochelle salt 60g / l
      Temperature 50 ℃
      Current density 2A / dm2
      1 minute
  As a result, a power feeding layer 130 composed of the electroless plating layer 131 and the strike copper plating layer 136 was formed.
(Fig. 2 (e))
  The sheet resistance of the power feeding layer 130 was 0.4Ω.
  Also in this example, a wiring layer having a width of 15 μm was formed on the polyimide layer 110, but the wiring was formed uniformly.
[0026]
【The invention's effect】
As described above, the present invention provides a method for forming a power supply layer on an insulating layer made of a polyimide layer and forming a wiring layer thereon by selective plating by electrolytic plating. It is possible to provide a wiring formation method that can form a wiring with good adhesion using a power feeding layer in which an oxide film is not formed on the surface of the electroless nickel plating layer as in the prior art.
At the same time, it is possible to provide a wiring member in which wiring is formed by such a wiring forming method.
[Brief description of the drawings]
FIG. 1 is a process cross-sectional view of an example of an embodiment of a wiring forming method of the present invention.
FIG. 2 is a partially enlarged cross-sectional view of FIG. 1C for explaining a manufacturing method and a layer configuration of a power feeding layer 130;
[Explanation of symbols]
110 Polyimide layer
120, 125 copper foil
130 Feeding layer
131 Electroless nickel plating layer
132 Electroless copper plating layer
133 Electrolytic nickel plating layer
134 Electrolytic copper plating layer
135 Strike nickel plating layer
136 Strike copper plating layer
140 resist layer
150 Electrolytic plating layer

Claims (5)

A method of forming wiring on a polyimide layer, in which (a) a surface for forming wiring of a polyimide layer is formed in a roughened state, and (b) a polyimide layer A power feeding layer forming step of providing a power feeding layer for electrolytic plating formation of a main layer for forming wiring on the roughened surface, and (c) wiring for selective plating formation by electrolytic plating on the power feeding layer. A resist layer forming step for forming a resist layer having a combined opening; (d) a wiring layer forming step for electrolytically forming a main layer for forming wiring on the power feeding layer; and (e) necessary after removing the resist layer. And a soft etching process that removes the exposed power feeding layer by soft etching so as not to damage the wiring. The power feeding layer forming process imparts a catalyst for electroless plating, Electrolysis After forming the electroless nickel plating layer performs Kell plating, further in an electroless nickel plating layer, a metal layer to reduce the resistance of the power supply layer state, and are not to form a resistance metal layer Teika The formation of the metal layer for decreasing the resistivity is performed in the order of electroless nickel plating and electrolytic copper plating in succession to the electroless nickel plating. A method of forming a wiring, characterized by comprising: A method of forming wiring on a polyimide layer, in which (a) a surface for forming wiring of a polyimide layer is formed in a roughened state, and (b) a polyimide layer. A power feeding layer forming step of providing a power feeding layer for electrolytic plating formation of a main layer for forming a wiring on the roughened surface, and (c) wiring for selective plating formation by electrolytic plating on the power feeding layer. A resist layer forming step for forming a resist layer having a combined opening, (d) a wiring layer forming step for electrolytically forming a main layer for forming wiring on the power feeding layer, and (e) necessary after removing the resist layer And a soft etching process for removing the exposed power feeding layer by soft etching so as not to damage the wiring. The power feeding layer forming process imparts a catalyst for electroless plating and Electrolysis After forming the electroless nickel plating layer by performing Kel plating, a metal layer for reducing the resistivity, which is a metal layer for reducing the resistance of the power feeding layer, is formed on the electroless nickel plating layer. The method of forming a wiring according to claim 1, wherein the formation of the resistivity lowering metal layer is performed by sequentially performing nickel strike plating, electrolytic nickel plating, and electrolytic copper plating after electroless nickel plating. 3. The wiring forming method according to claim 1, wherein the roughened polyimide layer forming step forms a roughened surface by a wet blast method. 4. 3. The wiring forming method according to claim 1, wherein the roughened polyimide layer forming step etches and removes the metal foil of the laminated material in which the polyimide layer is formed on the rough surface of the metal foil. Then, the wiring forming method is characterized in that the surface exposed by etching is roughened. A wiring member in which wiring is formed on a polyimide layer, wherein the wiring is formed by the wiring forming method according to any one of claims 1 to 4 .

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