JPH08316612A - Printed circuit board and manufacturing method - Google Patents

Abstract

PURPOSE: To provide a manufacturing method for a printed circuit board, in which a catalytic process time is reduced with good adhesiveness and insulation in conductive pattern. CONSTITUTION: An adhesive layer is formed on at least one surface of board. The surface of the adhesive layer is roughened and activated in a solution including catalytic kernel. An electroless plating step is carried out to form a conductive pattern. The catalytic kernel is made of a complex including noble-metal ions and amino-based complexing agent, and the donating quantity of the catalytic kernel is adjusted in a formula on a noble-metal basis, 1.0μg/ cm<2> <=(CV/A)<=5.0μg/cm<2> , where CV is the quantity of catalyst (μg) on a noble- metal basis, and A is a projected area of the board (before roughening, cm<2> ).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed wiring board and a method for manufacturing the same, and more particularly to a technique for applying a catalyst when a conductor pattern is formed by an additive process.

[0002]

2. Description of the Related Art In recent years, electronic parts have been miniaturized, improved in performance, and increased in functionality, and various printed wiring boards used therein have high density, multi-layered and high-density by forming fine patterns. Reliability is required.

As a general method for forming a conductor pattern on a printed wiring board, a subtractive process (etched foil) is used to form a conductor pattern by etching a copper clad laminate obtained by sticking a copper foil to an insulating substrate. Process) is conventionally known. This process has an advantage that a conductor pattern having excellent adhesion with an insulating substrate can be obtained, but has a drawback that undercutting occurs because patterning by etching has a large etching depth. Therefore, it is considered that a highly accurate conductor pattern cannot be obtained by this process, and it is difficult to cope with high density. Therefore, recently, a full additive process has attracted particular attention as an alternative method to the subtractive process.

In a typical full additive process,
First, an adhesive layer is formed by applying an adhesive on the surface of the substrate, the surface of the adhesive layer is roughened, and then electroless plating is performed to form a desired conductor pattern. Further, according to this process of performing electroless plating after resist formation, there is a feature that a conductor pattern with higher density and higher precision can be obtained than in the subtractive process.

When carrying out electroless plating for forming a conductor pattern, usually, a step of applying active palladium as a catalyst for inducing initial deposition of plating to a substrate is indispensable. However, in the additive process, since the catalyst applying step is performed before the resist forming step,
There is a problem that the catalyst always remains under the resist between the conductor patterns. Therefore, when the pitch between the patterns is 100 μm or less, particularly 50 μm or less, the insulating property between the patterns cannot be sufficiently secured because the catalyst is a conductor.

Under the circumstances as described above, attempts have been made so far to secure the insulating property by reducing the catalyst application amount using a Pd-Sn colloidal catalyst. However, when using catalyst nuclei of the same type and size, reducing the amount of catalyst applied simultaneously leads to a decrease in the number of active sites. Therefore, if the above-mentioned trial is carried out, it becomes difficult to deposit the electroless plating, and the desired conductor pattern cannot be formed.

Further, considering the activity of the Pd catalyst, P
Since the d-Sn colloidal catalyst is used to reduce Pd ²⁺ to Pd ⁰ by using stannous chloride, which is a reducing agent, to give a particle nucleus of metallic palladium, tin ions as impurities are resisted. It has the disadvantage that it remains below and increases the surface resistance. Therefore, in order to maintain both the deposition amount of electroless plating and high insulation between patterns, it is important to select a catalyst that can effectively give active palladium without impurities.

[0008]

As a catalyst capable of eliminating the above-mentioned inconvenience, for example, practical surface technology VOL.34 (4) p120
~ 124 (1987), there is a catalyst using a Pd colloid. In this catalyst, the particle nucleus is smaller than that of the Pd-Sn colloidal catalyst, and the oxidation number of Pd is zero.
It has a feature that n-ions and the like are unnecessary. therefore,
It is considered that the use of this improved catalyst can prevent a decrease in surface resistance, and thus a conductor pattern having high insulation reliability can be obtained.

However, since the above Pd colloidal catalyst does not have an electric charge, it has a characteristic that it is difficult to be adsorbed on the roughened surface of the adhesive layer. Therefore, if the catalyst application time is short, the catalyst application amount and the plating deposition amount tend to vary, and as a result, it becomes difficult to form the conductor pattern. Therefore, in order to avoid such problems,
It is necessary to set the treatment time in the catalyst application step to a very long time (usually at least about 1 hour) and apply a sufficient amount of catalyst to the roughened surface. Therefore, in order to improve the production efficiency of the printed wiring board, a method capable of applying a sufficient amount of catalyst in a shorter time is desired. Of course, in that case, it is a precondition that the adhesion and insulation of the conductor pattern are not impaired.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a printed wiring capable of shortening the time of the catalyst application step while maintaining the adhesion and insulation of the conductor pattern. It is to provide a method for manufacturing a plate.

Another object of the present invention is to provide a printed wiring board having high reliability.

[0012]

Means for Solving the Problems In order to solve the above problems, the inventors of the present invention have conducted earnest research, and have obtained suitable findings. Then, the present inventors have completed the following invention based on this knowledge.

That is, according to the first aspect of the invention, an adhesive layer is formed on the surface of at least one of the substrates, the surface of the adhesive layer is roughened, and then an activation treatment is performed with a treatment liquid containing a catalyst nucleus. In the method for producing a printed wiring board in which a conductor pattern is formed by performing electroless plating, a complex consisting of a noble metal ion and an amino-based complexing agent is used as the catalyst nucleus, and the amount of the catalyst nucleus provided is The gist is a method for manufacturing a printed wiring board, which is controlled so as to satisfy the following formula in terms of noble metal.

1.0 μg / cm ² ≤ (CV / A) ≤5.
0 μg / cm ² CV: Noble metal equivalent catalyst amount (μg) A: Projected area of substrate (area before roughening, cm ² ) In the invention according to claim 2, in claim 1, the amino-based complexing agent Is 2-aminopyridine.

According to a third aspect of the present invention, in the first aspect, the catalyst nucleus-containing treatment liquid is an alkaline solution containing palladium ions and 2-aminopyridine.

According to a fourth aspect of the invention, in the first aspect, the surface of the roughened adhesive layer is negatively charged. The invention according to claim 5 is a printed wiring board in which a conductor pattern is formed by electroless plating via a catalyst nucleus provided on a roughened surface of an adhesive layer provided on at least one substrate surface, the catalyst nucleus is composed of a noble metal ions and amino-based complexing agent, application amount of the catalyst nucleus is 1.0μg / cm ² ~5.0μg / cm ² with respect to the projection area of the substrate with a noble metal in terms of printing The wiring board is the gist.

[0017]

The treatment liquid containing the catalyst nucleus used in the present invention contains a complex composed of a noble metal ion and an amino complexing agent as the catalyst nucleus. In addition, a characteristic of this catalyst nucleus formed by chelating a noble metal ion with an amino complexing agent is that it is positively charged, unlike a colloidal catalyst that is uncharged. Here, it has been confirmed by experiments by the present inventors that when the roughening liquid is used to roughen the adhesive layer, the surface of the adhesive layer is slightly negatively charged. It is considered that this is because residual functional groups and bonds of the resin forming the adhesive layer are decomposed by a roughening liquid such as an acid or an oxidizing agent. Therefore, when performing the activation treatment with the treatment liquid containing the catalyst nucleus,
The complex is electrostatically adsorbed on the roughened surface. Therefore,
A sufficient amount of the catalyst can be applied to the adhesive layer in a short time as compared with the case of using a colloidal catalyst having no electric charge. Further, since the catalyst of the present invention does not contain Sn, the surface resistance does not decrease and the insulating property between patterns is excellent.

Further, in the present invention, the amount of catalyst nuclei applied per projected area of the substrate (area before roughening) is controlled. The reason for this is as follows. Generally, when forming a conductor pattern on a resin insulation layer, a catalyst is applied after roughening the surface of the resin insulation layer. At that time, it is considered that the catalyst is applied in consideration of the area inside the anchor dent due to the roughening. However, according to an experiment conducted by the inventors, it was found that when the catalyst is applied in consideration of the area inside the anchor recess, the insulation between the patterns is deteriorated. Therefore, the amount of catalyst nuclei applied per projected area of the substrate (area before roughening) is controlled. The size (average diameter) of the catalyst nucleus (active point) of the catalyst composed of the noble metal ion and the amino complexing agent is about several tens of liters, and the catalyst activity is inversely proportional to this size. From this, it is preferable that the amount of catalyst nuclei applied is controlled according to the size of the catalyst nuclei. For example, the average diameter of the catalyst nuclei may be set to 1Å to 500Å, preferably 5Å to 100Å. This is because it is difficult to produce catalyst nuclei with a volume of less than 1Å. On the other hand, if this value exceeds 500 Å, the insulation resistance decreases and it becomes impractical.

In the present invention, the amount of catalyst nuclei applied per projected area of the substrate (area before roughening) is, in terms of noble metal,
^{0.01μg / cm 2 ~10.0μg / cm 2} , preferably from being controlled in the range of ^{1.0μg / cm 2 ~5.0μg / cm 2} . This amount is 0.01 μg / cm ²
If it is less than the above range, the deposition of the electroless plating will be insufficient and pattern formation will be difficult. On the other hand, 10.0 μg / cm ²
If it exceeds, the insulation resistance value becomes small, and it becomes impossible to secure high reliability for the substrate.

Next, a method for manufacturing the printed wiring board of the present invention will be described. First, an additive adhesive layer is formed by a conventional method on the surface of a substrate such as a resin substrate such as a glass epoxy substrate or a polyimide substrate, a ceramic substrate such as an alumina substrate or an aluminum nitride substrate, or a metal substrate such as a phosphor bronze substrate. To do. Here, as the adhesive used in the production method of the present invention, a pre-cured heat-resistant resin fine powder that is soluble in an acid or an oxidant is difficult to resist against an acid or an oxidant by the curing treatment. It is desirable that it be dispersed in an uncured heat-resistant resin liquid that exhibits solubility characteristics. The adhesive layer may be formed on only one side of the substrate, or may be formed on both sides of the substrate.

Then, the surface of the adhesive layer is chemically roughened by a conventional method using a roughening liquid such as an acid or an oxidizing agent. When this treatment is performed, the heat-resistant resin fine powder in the adhesive layer is mainly dissolved and removed, so that many fine anchor depressions are formed on the surface of the adhesive layer. Then, through this treatment, the substrate surface is slightly charged negatively. The surface roughness of the roughened surface of the adhesive layer is JI
Rmax = 5 μm to 20 μ as measured by S B 0601
It is preferably m. If the surface roughness is less than 5 μm, the desired peel strength cannot be obtained, and the adhesiveness of the conductor pattern deteriorates. On the other hand, if the surface roughness exceeds 20 μm, L
It becomes impossible to realize a fine pattern of / S = 100 μm / 100 μm or less. Moreover, in this case, since the substantial surface area of the substrate becomes large, it may not be possible to sufficiently deposit the plating by setting the above-mentioned catalyst nucleus application amount.

Next, the surface of the roughened adhesive layer is activated to fix the catalyst nuclei on the roughened surface.
The activation treatment in the present invention includes, for example, 1) cleaner treatment (degreasing) under alkaline conditions, 2) cleaning, 3) cleaner treatment under acidic conditions, 4) cleaning, and 5) soft etching under acidic conditions. , 6) washing, 7) pre-dip in preliminary bath, 8) treatment of catalyst nucleus-containing treatment liquid under alkaline conditions (catalyst imparting treatment), 9) washing, 10) reduction, 11) washing. It is achieved by

The cleaner treatment is carried out to remove oils and fats attached to the adhesive layer. It has been confirmed that negative charges are accumulated on the surface of the substrate even after the cleaner treatment under acidic conditions. The soft etching is performed in order to remove oil and fat attached to the metal surface. The predip is performed to prevent the soft etching solution from being brought into the processing solution containing the catalyst nuclei. Then, when the reducing step is performed, the adsorbed complex is decomposed.

Here, the activation treatment in the present invention is preferably performed under the following conditions. (1) The treatment liquid containing the catalyst nucleus needs to be a complex composed of a noble metal ion and an amino complexing agent as described above. In this case, the treatment liquid is most preferably an alkaline solution containing a complex composed of Pd ions and 2-aminopyridine. The reason is that Pd ²⁺ adheres to the substrate as an aggregate because the complex is less likely to be formed in the acidic region. In addition, in the alkaline region, the complex has an excessive complexing power, so that the post-treatment makes it easier to remove the complexing agent and expose Pd ⁰ . The hydrogen ion concentration of the treatment liquid is pH = 10 to 13
It should be about the degree. The reason is that when pH <10, it is difficult to form a complex, and when pH> 13, the complexing force is too strong and the applied amount decreases, and the complexing agent cannot be removed. Further, the amount of Pd ions in the treatment liquid is preferably 0.08 g / l to 0.2 g / l. The reason is that if it is less than 0.08 g / l, the peel strength cannot be obtained, and if it exceeds 0.2 g / l, the insulation resistance is lowered. The amount of 2-aminopyridine in the treatment liquid is preferably 1.5 g / l to 2.5 g / l. The reason is that if the amount is less than 1.5 g / l, the complexing agent is too small to allow Pd ^{2+ to} be stably present in the liquid, and if the amount exceeds 2.5 g / l, the amount of catalyst applied decreases. Because it will be.

Further, the reason why the amino-based complexing agent should be selected as the complexing agent for forming the complex is as follows. That is, the amino-based complexing agent has a high affinity for resin materials such as epoxy resin, but has a low affinity for metal materials such as copper. For this reason,
The complex that is the catalyst nucleus is difficult to be adsorbed on the metal surface,
Conversely, it tends to be selectively adsorbed to the roughened surface of the adhesive layer. That is, since the amount of catalyst nuclei adsorbed at the interface between the inner layer conductor pattern and the conductor pattern formed thereon is small, the resistance of the via hole formed can be reduced.

Examples of such an amino-based complexing agent include 2-aminopyridine. This is because 2-aminopyridine easily forms a complex with a noble metal ion and is well soluble in an alkaline aqueous solution.

The reason why the Pd ion should be selected as the noble metal ion forming the complex is that it has the highest catalytic property for electroless copper-nickel plating. In addition to Pd ions, platinum group metals such as Pt and Rh and ions such as Au and Ag can be selected as the noble metal ions.

(2) The treatment concentration of the catalyst nucleus-containing treatment liquid is preferably 1 mmol / l to 5 mmol / l in terms of noble metal. This is because if the concentration is less than 1 mmol / l, the required treatment time becomes long, which is not practical in production. On the other hand, when the concentration exceeds 5 mmol / l, the applied amount is too large and the surface resistance value is lowered.

(3) The treatment temperature of the treatment liquid containing the catalyst nucleus is 1
It is preferably 0 ° C to 80 ° C. This temperature is 10 ℃
When it is less than the above, the diffusion rate of the catalyst nucleus becomes small. For this reason, there arises inconveniences such as an increase in the time required for the treatment, and an inability to adhere a sufficient amount of catalyst nuclei even if the treatment time is extended. On the other hand, when the temperature exceeds 80 ° C., there is no problem with the decrease in diffusion rate, but heating with a heater or the like is required. Therefore, there is a possibility that the cost will increase due to an increase in the amount of capital investment.

(4) The cleaning performed between the steps in the activation treatment, particularly the cleaning performed after the treatment of the catalyst nucleus-containing treatment liquid, is carried out by immersion in running water, bubbling, ultrasonic waves or spraying. The method is preferred. In that case, it is preferable to repeat the treatment at 10 ° C. to 80 ° C. for 1 minute three times. The reason why the cleaning temperature is set within the above range is that the expected effect cannot be obtained below 10 ° C, and the applied catalyst falls off from the substrate above 80 ° C.

(5) The treatment of the catalyst nucleus-containing treatment liquid is preferably carried out after washing with water or an aqueous solution having a pH of 7 to 10. The reason for cleaning with a neutral or weakly alkaline solution is that it is easy to remove the excess catalyst that is not adsorbed on the roughened surface. When washed with acid,
Pd ²⁺ aggregates and adheres to the substrate.

(6) The treatment of the treatment liquid containing the catalyst nucleus is carried out once /
It is preferably carried out in a processing container which is circulated and stirred at a rate of time to 100 times / hour. The reason for this is that if the stirring is circulated, the catalyst will be easily spread over the whole body, and the catalyst application time will be further shortened.

(7) Negative of bath for treating treatment liquid containing catalyst nucleus
The load is 0.1 dm² / L-10dm ² Set to / l
Is preferred. Bath load is 0.1 dm² / L is less than
That is because productivity becomes worse. On the other hand, the bath load is 10
dm² If it exceeds / l, the liquid circulation becomes poor and the amount of catalyst applied
This is because the variation of is large.

(8) In the activation treatment, the drying temperature for fixing the catalyst is preferably set to 40 ° C to 200 ° C. The reason is that when the drying temperature is lower than 40 ° C., the immobilized state of the catalyst core becomes unstable, and the drying temperature is 200
This is because if the temperature exceeds ° C, the heat resistant temperature of the substrate will be exceeded.

If the charge amount is too small, the force for adsorbing the complex on the substrate becomes weak and the catalyst application time cannot be sufficiently shortened. Therefore, the charge amount is increased by the roughening treatment and the cleaner treatment. It is desirable to be strict.

Next, a film-shaped resist is placed on the surface of the adhesive layer on which the catalyst has been applied and fixed, and the resist is laminated under pressure and heating conditions. When the resist is composed of a photosensitive resin composition, then exposure / development, U
The resist is patterned by V cure and heat treatment. After that, a conductor pattern is formed on the resist non-forming portion by performing electroless plating using an electroless copper plating bath or the like by a conventionally known method. The printed wiring board of the present invention is manufactured as described above.

The printed wiring board of the present invention produced in this manner has a conductor pattern formed by electroless plating through the catalyst nuclei provided on the roughened surface of the adhesive layer provided on at least one substrate surface. Formed. The catalyst nucleus is composed of a noble metal ion and an amino-based complexing agent, and the amount of addition is 1.
It has become ^{0μg / cm 2 ~5.0μg / cm 2} . Further, as described above, the conductor pattern of the printed wiring board manufactured in this manner ensures excellent adhesion and insulation. Therefore, the printed wiring board has high reliability.

[0038]

EXAMPLES In the following, in order to explain in detail the examples in which the present invention is embodied in a printed wiring board and a method for manufacturing the same, the procedure for preparing the best mode sample 1 will be described.

(Preparation of Sample 1) Step (1): 60 parts by weight of bisphenol A type epoxy resin (made by Yuka Shell), 40 parts by weight of phenol novolac type epoxy resin (made by Yuka Shell), imidazole type curing agent (Shikoku 5 parts by weight of Kasei), 25 parts by weight of an epoxy resin fine powder (made by Toray) having an average particle size of 5.5 μm, 10 parts by weight of an average particle size of 0.5 μm, and a surface conditioner (made by San Nopco) Was mixed and then kneaded with a three-roller while adding 10 parts by weight of acetic acid-n-butoxyethyl acetate to prepare an adhesive solution.

Step (2): The adhesive solution prepared in the step (1) was applied by a roll coater (manufactured by Dainippon Screen) on a glass epoxy resin substrate which was buffed once in the vertical direction and once in the horizontal direction. . Then, the adhesive solution applied in this way is heated at 80 ° C. for 3 hours and then at 100 ° C. for 1 hour.
Heat treatment was performed at 120 ° C. for 3 hours and at 150 ° C. for 15 hours. By this treatment, the adhesive solution was cured to form an adhesive layer of 60 μm.

Step (3): The substrate on which the adhesive layer is formed is treated with a chromic acid aqueous solution (CrO ₃ ,
The surface of the adhesive layer was roughened by immersion in 800 g / l) for 30 minutes. Surface roughness of adhesive layer (Rmax)
JIS B 06 using a surface roughness meter (manufactured by Tokyo Seimitsu Co., Ltd.)
When measured according to 01, Rmax = 10 ± 2 μm
(6 points average).

Step (4): The substrate whose surface is roughened is
The activation treatment was performed by the following procedures 1) to 11). 1) Cleaner treatment under alkaline conditions: 85 ml / l of trade name "CLEANER SECURIGANT HC-F45" (manufactured by Atotech Japan Co., Ltd.) and 20 g of NaOH
The substrate was immersed in a treatment liquid containing 1 / l at 60 ° C. for 5 minutes.

2) Cleaning: The substrate was immersed in running water at 25 ° C. for 1 hour.
The soaking for 3 minutes was repeated 3 times. 3) Cleaner treatment under acidic conditions: Trade name "CLEANER SECURIGANT HC-F45" (manufactured by Atotech Japan Co., Ltd.), 85 ml / l, H ₂ SO ₄ (98
%) Was immersed in a treatment liquid containing 20 ml / l at 35 ° C. It should be noted that the immersion time of the substrate in the treatment liquid is 5
I decided to set it to minutes.

4) Washing: The substrate was immersed in running water at 25 ° C. for 1 hour.
The soaking for 3 minutes was repeated 3 times. 5) Soft etching: 150g of sodium persulfate
/ L and H ₂ SO ₄ (98%) in 100 ml / l of the soft etching solution, the substrate was immersed at 30 ° C for 1 minute.

6) Cleaning: The substrate was immersed in running water at 25 ° C. for 1 hour.
The soaking for 3 minutes was repeated 3 times. 7) Pre-dip: 20 ml of product name "Pre-dip Neo Gantt B" (manufactured by Atotech Japan Co., Ltd.)
/ L and H ₂ SO ₄ (98%) at 1 ml / l, the substrate was immersed for 1 minute at room temperature.

8) Application of catalyst: 0.2 g of Pd ions /
1, 2-aminopyridine 2.0 g / l, NaOH 4
g / l, the H ₃ BO ₃ containing 5g / l, pH = 10.5~
A treatment liquid containing 11.5 catalyst nuclei was prepared. In this example, specifically, a trade name "Activator Neogant 834 Conc" manufactured by Atotech Japan Co., Ltd. was used, and NaOH was mixed thereinto to prepare the treatment liquid. Then, the substrate is added to this treatment liquid.
It was immersed at ℃ for 5 minutes. In this treatment, the circulating stirring of the treatment bath was once / hour, the bath load was 5 dm ² / l, and the size (average diameter) of the catalyst nucleus was 10Å (Table 1
reference). Then, after the immersion treatment, the catalyst was fixed to the adhesive layer by drying at 150 ° C. Since it takes about 5 minutes to apply the catalyst, it is confirmed that the surface of the roughened surface is negatively charged.

9) Washing: The substrate was immersed in running water at 25 ° C. for 1 hour.
The soaking for 3 minutes was repeated 3 times. 10) Reduction: Product name "Reducer Neo Gantt W
A "(Atotech Japan Co., Ltd.) 5 ml /
l, H ₃ BO ₃ in a processing solution containing 5 g / l
It was immersed at 0 ° C. for 5 minutes.

11) Cleaning: Immersing the substrate in running water at 25 ° C. for 1 minute was repeated 3 times. By carrying out each of the above steps, catalyst nuclei were provided and fixed to the roughened adhesive layer.

Step (5): The amount of Pd applied on the substrate by the treatment of the step (4) was measured according to the following method. That is ,. 3 substrates of 5 cm x 5 cm that adsorbed Pd were placed in a beaker, and 6 N hydrochloric acid (manufactured by Kanto Kagaku) 20 m
1 was added. ． After standing for 2 hours, 20 ml of a reducing solution (25 g of ascorbic acid + 10 g of hydroxylamine hydrochloride / 100 l) was added to the beaker, 10 ml of 10% potassium iodide (manufactured by Kanto Kagaku) was added, and 0.5% sodium sulfite was added. The final volume was adjusted to 100 ml by adding 1 ml (manufactured by Kanto Kagaku).
． The absorbance of the solution adjusted to 100 ml was measured. And 1 mg / l to 10 m in Pd conversion in advance
The concentration of Pd was calculated from the above measurement results based on a calibration curve prepared by measuring the absorbance of the solution adjusted to g / l. As a result, the applied amount of Pd was 1.5 μg / cm ² (see Table 1). That is, it was found that a sufficient amount of Pd was surely applied even when the immersion time in the catalyst nucleus-containing treatment liquid during the activation treatment was as short as 5 minutes.

Step (6): A plating resist (manufactured by San Nopco) was formed on the substrate subjected to the catalyst application treatment in the step (4) by the following method. That is ,. A film-shaped photoresist is used under specified conditions (laminating pressure 3 kg,
It was laminated on a substrate at a temperature of 100 ° C. ． A resist pattern is formed by UV exposure (exposure amount: 100 mj / cm ² ), heat treatment (80 ° C., 5 minutes), development (20 ° C., 120 seconds) and heat treatment (80 ° C., 5 minutes) on a substrate laminated with a resist. Was formed. ． The substrate on which the resist pattern is formed is exposed to ultraviolet rays (exposure amount: 6
J / cm ² ) and heat treatment (120 ° C., 30 minutes) to cure the resist.

Step (7): The substrate is placed in a bath (70 ° C., 5
Minute) and then immersed in an electroless copper plating bath having the following composition for 8 hours by a conventional method. As a result, electroless copper plating with a thickness of 20 μm was deposited on the non-resist portion. As described above, the printed wiring board of Sample 1 having the conductor pattern as shown in FIG. 1 was manufactured.

・ Copper sulfate: 0.06 mol / l, ・ Formalin (37%): 0.30 mol / l, ・ Sodium hydroxide: 0.35 mol / l, ・ EDTA: 0.35 mol / l, ・ Additives: Small amount ・ Plating temperature: 70 ° C. ・ pH = 12.4. Step (8): With respect to the conductor patterns obtained as described above, the insulation resistance between the patterns and the peel strength of the conductor circuit were measured as follows.

That is, the comb-teeth pattern 2 of L / S = 25 μm / 25 μm was used to measure the insulation resistance between the patterns (see FIG. 1). Then, the substrate was placed in a constant temperature bath where the temperature and humidity were kept constant (85 ° C., 85%), and left for a long time with a constant voltage (24 V) being applied to the comb tooth pattern 2. Then, the insulation resistance (Ω) between the patterns was measured after 1000 hours had passed. The peel strength (kg / cm 2) between the conductor and the adhesive layer is measured by soldering a copper wire to the central portion of the measuring terminal connecting pad 1 connected to the comb pattern 2 and vertically connecting the copper wire. It was done by pulling. As a result, the peel strength is 1.7.
kg / cm, insulation between patterns is L / S = 25μm / 25μ
It was 1.7 × 10 ⁹ Ω in m.

In summary of the above results, the conductor pattern of Sample 1 of the present example has a suitable insulating property and peel strength, even though the catalyst application treatment is a very short time of 5 minutes. I found out that By the way, when such a production method was adopted, the same result could be obtained even when the treatment time of the catalyst nucleus-containing treatment liquid was shortened to 3 minutes.

(Preparation of Sample 2: When the treatment concentration of the catalyst nucleus-containing treatment liquid is low) In the step (4), the concentration of the catalyst nucleus-containing treatment liquid was set to 0.1 mmol / l in terms of Pd and the catalyst was Sample 2 was prepared in accordance with the method for preparing sample 1 except that the nucleus was added.
The amount of catalyst applied was as low as 0.005 μg / cm ² . However, the circuit could not be formed because the deposition of the electroless plating was insufficient. Therefore, neither peel strength nor insulation resistance could be measured. In addition, in order to produce a printed wiring board equivalent to Sample 1 under these conditions, at least 60 times the treatment liquid containing the catalyst nucleus was treated.
I had to do it for about a minute.

(Preparation of Sample 3: When the treatment concentration of the catalyst nucleus-containing treatment liquid is high) In the above step (4), the concentration of the catalyst nucleus-containing treatment liquid was set to 6.0 mmol / Pd equivalent to the catalyst nucleus. Sample 1 except that
Sample 3 was manufactured according to the manufacturing method described in 1. However, this treatment liquid has a high concentration and thus has a low insulation resistance. Further, since the catalyst nuclei are too much, the activity becomes extremely high, resulting in a rough plating surface.

(Preparation of sample 4: When the treatment temperature of the catalyst nucleus-containing treatment liquid is low) In the above step (4), except that the treatment temperature of the catalyst nucleus-containing treatment liquid was set to a low value of 1 ° C. In accordance with the manufacturing method of Sample 1,
Sample 4 was prepared. The amount of catalyst applied is 0.005μ
The value was as low as g / cm ² . However, under these conditions, it was not possible to form a circuit because the deposition of electroless plating was insufficient. Therefore, neither peel strength nor insulation resistance could be measured.

(Preparation of sample 5: When the treatment temperature of the catalyst nucleus-containing treatment liquid is high) In the above step (4), except that the treatment temperature of the catalyst nucleus-containing treatment liquid is set to a high value of 85 ° C. Sample 5 was manufactured according to the method of manufacturing sample 1. The amount of catalyst applied is 20μ
The value was g / cm ² , which was higher than the preferred range. In this case, the plating surface was roughened, resulting in a plating film having extremely low strength, so that the peel strength could not be measured. The insulating property between patterns when L / S = 25 μm / 25 μm was 10 ⁶ Ω. In addition, when producing this sample 5, it was essential to heat the catalyst nucleus-containing treatment liquid with a heater or the like, and for that purpose, capital investment was required.

(Preparation of Sample 6: When Water Rinse After Soft Etching Is Not Performed) In the above step (4), except that water rinsing after soft etching is not performed,
Sample 6 was manufactured according to the method of manufacturing sample 1. Then, as in the case of Sample 1, the insulation resistance between the patterns and the peel strength of the conductor circuit were measured. As a result, peel strength is 1.6kg / cm, L / S = 2
Inter-pattern insulation at 5 μm / 25 μm is 1.1 ×
It was 10 ¹⁰ Ω. In addition, according to the manufacturing method of this sample 6, the problem of non-adhesion with the inner layer copper conductor was observed.

(Preparation of Sample 7: When Washing with Water after Immersion of Catalyst Nucleus-Containing Treatment Solution) In the above step (4),
Sample 7 was prepared according to the preparation method of sample 1 except that water washing was not performed after the immersion of the catalyst nucleus-containing treatment liquid. Then, as in the case of Sample 1, the insulation resistance between the patterns and the peel strength of the conductor circuit were measured. However, when electroless copper plating was performed, plating was deposited on the resist, and a short circuit occurred between the patterns. Therefore, it was impossible to measure the insulation resistance of Sample 7. The peel strength was 1.4 kg / cm 2.

(Preparation of Sample 8: When Circulating and Stirring of Bath is not Performed) In the step (4), the stirring condition of the catalyst nucleus-containing treatment liquid is set to 0 times / hour, that is, stirring is not performed at all. Except for the above, Sample 8 was manufactured according to the manufacturing method of Sample 1. Then, as in the case of Sample 1, the insulation resistance between the patterns and the peel strength of the conductor circuit were measured. As a result, the peel strength was 1.5 kg / cm, and the insulating property between patterns when L / S = 25 μm / 25 μm was 9.2 × 10 ⁹ Ω. In addition, in order to manufacture a printed wiring board equivalent to Sample 1 under these conditions, it was necessary to perform the treatment with the catalyst nucleus-containing treatment liquid for about 20 to 30 minutes.

(Preparation of sample 9: When the number of circulation stirring in the bath is large) Preparation of sample 1 was carried out except that the stirring condition of the catalyst nucleus-containing treatment liquid was set to 200 times / hour in the step (4). Sample 9 was prepared according to the method. Then, as in the case of Sample 1, the insulation resistance between the patterns and the peel strength of the conductor circuit were measured. As a result, the peel strength is 1.6kg / cm, L /
The inter-pattern insulating property when S = 25 μm / 25 μm was 9.7 × 10 ⁹ Ω. The performance of Sample 9 obtained by setting these conditions was almost the same as the performance of Sample 1. On the contrary, there is a drawback that the equipment cost is required because the pump needs to be large.

(Preparation of Sample 10: When Bath Load is Small) Preparation of Sample 1 except that the bath load of the catalyst nucleus-containing treatment liquid is set to 0.05 dm ² / l in the step (4). Sample 10 was prepared according to the above. Then, as in the case of Sample 1, the insulation resistance between the patterns and the peel strength of the conductor circuit were measured. As a result, the peel strength is 1.5kg / cm, L /
The insulating property between patterns when S = 25 μm / 25 μm was 2.0 × 10 ¹⁰ Ω. It should be noted that according to this condition setting, although the same thing as Sample 1 was obtained, the productivity was poor and it was not practical.

(Preparation of Sample 11: When bath load is large) In the above step (4), the preparation method of Sample 1 was used except that the bath load of the treatment solution containing catalyst nuclei was set to 200 dm ² / l. Then, the sample 11 was manufactured. The amount of catalyst applied was 0.005 μg / cm ² .
However, because the deposition of electroless plating was insufficient,
The circuit could not be formed. Therefore, neither peel strength nor insulation resistance could be measured. In addition, in order to produce a printed wiring board equivalent to Sample 1 under these conditions, it was necessary to treat the catalyst nucleus-containing treatment liquid for about 30 minutes.

(Preparation of Sample 12: When Drying Temperature is Low) In the above step (4), except that the temperature at the time of drying after immersion in the treatment solution containing the catalyst nucleus is 30 ° C., the preparation method of Sample 1 is as follows. In accordance with, sample 12
Was prepared. Then, as in the case of Sample 1, the insulation resistance between the patterns and the peel strength of the conductor circuit were measured. However, when electroless copper plating was performed,
Plating was deposited on the resist, causing a short circuit between the patterns. Therefore, it was impossible to measure the insulation resistance of this sample 12. The peel strength was 1.0 kg / cm 2.

(Preparation of Sample 13: When Drying Temperature is High) In the above step (4), except that the temperature at the time of drying after immersion in the treatment liquid containing the catalyst nucleus is 250 ° C., the preparation method of Sample 1 According to, sample 1
3 was prepared. However, under these conditions, the substrate was burned due to high heat during drying, and eventually circuit formation was impossible. Therefore, neither peel strength nor insulation resistance could be measured.

(Preparation of Sample 14: When Pd Colloid Catalytic Nucleus is Used (1)) In preparation of Sample 14, after carrying out Steps (1) to (3) of Sample 1, The roughened surface on the substrate was activated by various procedures.

Step (4): 1) The substrate was immersed in a degreasing solution (made by Shipley) at 50 ° C. for 5 minutes. 2) The substrate was washed with water 3 times at 25 ° C. for 1 minute. 3) The substrate was immersed in an affinity liquid (made by Shipley) at 25 ° C for 2 minutes. 4) The substrate was washed with water 3 times at 25 ° C. for 1 minute. 5) The substrate was immersed in a copper foil etching solution (manufactured by Mitsubishi Gas Chemical Co., Inc.) at 25 ° C for 2 minutes. 6) The substrate was washed with water 3 times at 25 ° C. for 1 minute.
7) Add the above substrate to a copper foil surface cleaning solution (Kanto Kagaku)
It was immersed at ℃ for 2 minutes. 8) Put the above substrate on at 25 ℃ for 3 minutes
It was washed with water twice. 9) Pd colloid catalyst application liquid (manufactured by Toda Kogyo, aqueous supermona palladium colloid, concentration: P
The substrate was dipped in 2.5 mmol / l in terms of d. The immersion temperature and the immersion temperature are the same as in the case of producing the sample 1.
The temperature was set to 35 ° C for 5 minutes. In this treatment, the circulating stirring of the treatment bath was once / hour, the bath load was 5 dm ² / l, and the size (average diameter) of the catalyst nuclei was 30Å. Then, after the immersion treatment, the catalyst was fixed to the adhesive layer by drying at 150 ° C. 10) The substrate is 2
It was washed 3 times with water at 5 ° C for 1 minute.

Step (5): After the activation treatment as described above, the amount of Pd applied to the substrate was measured according to the method of the step (5) of Sample 1. As a result, the amount of Pd is 0.1
It was an extremely low value of 5 μg / cm ² . That is, in the case of this catalyst liquid having no electric charge, it was not possible to impart a sufficient amount of Pd in a treatment time as short as 5 minutes. Then, when electroless plating was carried out after this, the deposition of the plating was insufficient, so that eventually a circuit could not be formed. Therefore, neither peel strength nor insulation resistance could be measured.

(Preparation of Sample 15: When Pd colloid-based catalyst nucleus is used (2)) In the step (4) of Sample 14, except that the treatment time of the Pd colloid catalyst application liquid is set to 60 minutes. Is the same sample 1
The production method of 4 was applied. Under the above-mentioned condition settings, the catalyst application amount was 2.0 μg / cm ² . Therefore, electroless plating can be performed, and finally circuit formation can be performed. Then, as in the case of Sample 1, the insulation resistance between the patterns and the peel strength of the conductor circuit were measured. As a result, the peel strength was 1.
The insulating property between patterns was 1.2 × 10 ¹⁰ Ω when 7 kg / cm and L / S = 25 μm / 25 μm. In addition, according to this condition setting, since the treatment time of the catalyst liquid in the activation treatment requires 10 times or more, the sample 1
In comparison with the production of, the productivity was poor and not practical.

(Production of Sample 16: When Pd-Sn Colloid Catalyst is Used) In the production of Sample 16, after carrying out the steps (1) to (3) of Sample 1, the substrate was prepared by the following procedure. The roughened surface of was subjected to activation treatment.

Step (4): 1) The substrate was immersed in a degreasing solution (made by Shipley) at 50 ° C. for 5 minutes. 2) The substrate was washed with water 3 times at 25 ° C. for 1 minute. 3) The substrate was immersed in an affinity liquid (made by Shipley) at 25 ° C for 2 minutes. 4) The substrate was washed with water 3 times at 25 ° C. for 1 minute. 5) The substrate was immersed in a copper foil etching solution (manufactured by Mitsubishi Gas Chemical Co., Inc.) at 25 ° C for 2 minutes. 6) The substrate was washed with water 3 times at 25 ° C. for 1 minute.
7) Add the above substrate to a copper foil surface cleaning solution (Kanto Kagaku)
It was immersed at ℃ for 2 minutes. 8) Put the above substrate on at 25 ℃ for 3 minutes
It was washed with water twice. 9) The substrate was immersed in a Pd-Sn colloid catalyst application liquid (manufactured by Shipley, concentration: 5.0 mmol / l in terms of Pd). Sample 1
The temperature was set to 35 ° C. for 5 minutes, as in the case of manufacturing. In this treatment, the circulating stirring of the treatment bath was once / hour,
The bath load was 5 dm ² / l, and the size (average diameter) of the catalyst nuclei was 500 Å. After the immersion treatment, 1
The catalyst was fixed to the adhesive layer by drying at 50 ° C. 10) The substrate was washed 3 times with water at 25 ° C for 1 minute.
11) The substrate was placed in an activating solution (made by Shipley) at 25 ° C.
Soaked for 3 minutes. 12) The substrate was washed 3 times with water at 25 ° C. for 1 minute.

After the step (5), the manufacturing method of Sample 1 was basically followed. The Pd amount applied to the substrate after the activation treatment was measured and found to be 7.0 μg / cm ² . Also, as in the case of Sample 1, the insulation resistance between the patterns and the peel strength of the conductor circuit were measured. As a result, the peel strength was 1.
The insulating property between patterns was 4 × 10 ⁵ Ω when 4 kg / cm and L / S = 25 μm / 25 μm. That is, with such a manufacturing method, it is not necessary to set the catalyst application time so long, but it is not possible to secure suitable insulation and peel strength comparable to Sample 1. Therefore, the obtained printed wiring board of Sample 16 was inferior in reliability to Sample 1.

[0074]

[Table 1]

The present invention is not limited to the above embodiment, but can be modified as follows. (1) As a roughening agent other than chromic acid, for example, chromate or permanganate may be used.

(2) It is also possible to form the adhesive layer using a resin other than the photosensitive epoxy resin, for example, a photosensitive polyimide resin or a photosensitive BT resin. Moreover, these resins do not necessarily have photosensitivity.

Here, in addition to the technical ideas described in the claims, the technical ideas grasped by the above-mentioned embodiments and other examples will be listed below together with their effects. (1) A method of imparting catalyst nuclei to the adhesive layer by treating the adhesive layer formed on the surface of the substrate with a catalyst nucleus-containing treatment liquid, wherein the catalyst nuclei are either positive or negative. While selecting the charged one,
A method for applying a catalyst nucleus during the production of a printed wiring board, wherein the surface of the substrate is charged to a charge having a sign different from the charge of the catalyst nucleus before the treatment with the catalyst nucleus applying treatment liquid. With this method, the catalyst nucleus can be applied in a short time.

(2) In claim 1, the treatment concentration of the treatment liquid in the activation treatment is 1 mm in terms of noble metal.
ol / l to 5 mmol / l. With this method, the time required for the catalyst nucleus imparting treatment can be shortened.

(3) In claim 1, the treatment temperature of the treatment liquid in the activation treatment is 10 ° C to 80 ° C. With this method, it is possible to prevent an increase in equipment cost while shortening the time required for the catalyst nucleation treatment.

(4) In claim 1, the treatment of the treatment liquid in the activation treatment is performed in a treatment container in which the treatment liquid is circulated and stirred at a rate of 1 time / hour to 100 times / hour. To be seen. With this method, it is possible to prevent an increase in equipment cost while shortening the time required for the catalyst nucleation treatment.

The technical terms used in this specification are defined as follows. "Noble metal ion: In addition to the ions of the platinum group metals palladium, platinum, rhodium, etc., for example, gold ion, silver ion, etc."

[0082]

As described above in detail, according to the inventions described in claims 1 to 4, a print which can shorten the time of the catalyst application step while maintaining the adhesiveness and insulating property of the conductor pattern. A method for manufacturing a wiring board can be provided.
According to the invention of claim 5, it is possible to provide a printed wiring board having high reliability.

[Brief description of drawings]

FIG. 1 is a schematic view showing a comb tooth pattern for measuring insulation resistance and peel strength.

[Explanation of symbols]

 1 ... Pads for connecting measuring terminals, 2 ... Comb tooth pattern.

Claims (5)

[Claims] 1. An adhesive layer is formed on the surface of at least one of the substrates, the surface of the adhesive layer is roughened, an activation treatment is performed with a treatment liquid containing a catalyst nucleus, and then electroless plating is performed. In a method for producing a printed wiring board for forming a conductor pattern by using a complex composed of a noble metal ion and an amino-based complexing agent as the catalyst nucleus, the amount of the catalyst nucleus added should satisfy the following formula in terms of noble metal. Controlling printed wiring board manufacturing method. 1.0 μg / cm ² ≦ (CV /A)≦5.0 μg / cm
² CV: amount of catalyst converted to precious metal (μg) A: projected area of substrate (area before roughening, cm ² ) 2. The method for manufacturing a printed wiring board according to claim 1, wherein the amino complexing agent is 2-aminopyridine. 3. The method for producing a printed wiring board according to claim 1, wherein the treatment liquid containing the catalyst nucleus is an alkaline solution containing palladium ions and 2-aminopyridine. 4. The method of manufacturing a printed wiring board according to claim 1, wherein the surface of the roughened adhesive layer is negatively charged. 5. A printed wiring board in which a conductor pattern is formed by electroless plating via a catalyst nucleus provided on a roughened surface of an adhesive layer provided on at least one substrate surface, wherein the catalyst nucleus is consists of a noble metal ions and amino-based complexing agent, 1.0 [mu] g / cm ² with respect to the projected area of the substrate deposition volume in the noble metal in terms of the catalyst nuclei ~5.0μg / cm ²
Printed wiring board.