KR102376557B1 - Etching liquid and etching method of resin composition - Google Patents

Abstract

An etchant useful for a resin composition comprising an alkali-insoluble resin, 20 to 40 mass% of an organic filler, and 30 to 50 mass% of an inorganic filler, and the like is provided. 15 to 45 mass % of an alkali metal hydroxide as the first component and 1 to 40 mass % of an ethanolamine compound as the second component, and further contains at least one third component selected from an alcohol compound and a carboxylic acid compound An etchant for a resin composition, and an etching method using the etchant.

Description

Etching liquid and etching method of resin composition

The present invention relates to an etchant (etchant of a resin composition) and an etching method for etching a resin composition or the like containing an alkali-insoluble resin, 20 to 40 mass% of an organic filler, and 30 to 50 mass% of an inorganic filler.

In recent years, along with miniaturization and high performance of electronic devices, in circuit boards, formation of fine wiring, reduction of the coefficient of thermal expansion of insulating materials and substrate materials, reduction in dielectric constant, reduction in dielectric loss tangent, etc. are required. Among them, as a means of lowering the coefficient of thermal expansion of the insulating material, a method of making the insulating material highly filled, ie, increasing the content of the inorganic filler in the insulating material, is known. Moreover, use of alkali-insoluble resin excellent in moisture resistance is proposed as an insulating material, including an epoxy resin, a phenol novolak-type hardening|curing agent, a phenoxy resin, a cyanate resin, etc. It is preferable to use a filler with a low dielectric constant as a means of low-dielectric constant-ization of an insulating material, and low dielectric constant tangent, For example, using organic fillers, such as a fluororesin powder, is known. The insulating resin composition containing these inorganic fillers, organic fillers, and alkali-insoluble resins has excellent physical properties such as heat resistance, dielectric properties, mechanical strength, chemical resistance, etc., and is used for the outer layer surface of the circuit board as a solder resist or multi-layer build Widely used as an interlayer insulating material used for up wiring boards is being considered.

1 : is a schematic cross-sectional structural diagram of the soldering resist pattern which covered with the resin composition layer 4 other than the connection pad 3 soldered on a circuit board. The structure shown in FIG. 1 is called an SMD (Solder Masked Defined) structure, and the opening part of the resin composition layer 4 is smaller than the connection pad 3, It is characterized by the above-mentioned. The structure shown in FIG. 2 is called a NSMD (Non Solder Masked Defined) structure, and the opening part of the resin composition layer 4 is larger than the connection pad 3, It is characterized by the above-mentioned.

The opening of the resin composition layer 4 in FIG. 1 is formed by removing a part of the resin composition layer. As a processing method for removing the resin composition layer containing the resin composition containing an inorganic filler and alkali-insoluble resin, well-known methods, such as a drill, a laser, plasma, and a blast, can be used. Moreover, these methods can also be combined as needed. Among them, processing by lasers such as carbon dioxide laser, excimer laser, UV laser, and YAG laser is the most common, and laser light irradiation removes a part of the resin composition layer 4 and penetrates for through-hole formation Through-holes and non-through-holes, such as a hole, the opening part for via-hole formation, and the opening part for connection pad 3 formation, can be formed (refer patent documents 1 and 2, for example).

However, in processing by laser light irradiation, for example, when a carbon dioxide gas laser is used, a large number of shots is required, and desmear treatment is performed using an oxidizing agent made of an aqueous solution such as chromic acid or permanganate as a post-treatment. there is Moreover, when an excimer laser is used, the time required for processing becomes very long. Further, in the case of UV-YAG laser, compared with other laser beams, it has an advantage in that it can perform fine processing, but there is a problem that not only the resin composition layer but also the metal layer existing in the vicinity are simultaneously removed.

In addition, when laser light is irradiated to the resin composition layer, light energy is absorbed by the object at the irradiation site, and the object generates excessive heat according to specific heat. There were cases where defects occurred. Moreover, with respect to this heat_generation|fever, although it was proposed to use a thermosetting resin in a resin composition layer, when a thermosetting resin was used, a crack may become easy to generate|occur|produce in a resin composition layer.

As a method other than laser beam irradiation, the method of removing a resin composition layer with a wet blast method is mentioned. After forming the resin composition layer on the circuit board which has a connection pad on the insulating board|substrate, after hardening process and forming the resin layer for forming the mask for wet blasting on the resin composition layer, exposure and development By doing so, a pattern-shaped mask for wet blasting is formed. Next, by performing wet blasting, the resin composition layer is removed, an opening part is formed, and the mask for wet blasting is then removed (for example, refer patent document 3).

However, in the processing by wet blasting, the thickness that can be polished by one blasting process is small, and it is necessary to repeat the blasting process several times. Therefore, not only does the time taken for polishing become very long, but the portion to which the resin composition layer is adhered is on the connection pad or on the insulating substrate, and depending on the difference in the material, uniform polishing cannot be performed or residual It was very difficult to perform a process with high precision, such as water coming out.

As a processing method for removing a resin composition layer comprising a resin composition containing an inorganic filler and an alkali-insoluble resin, an etching method performed by immersion treatment using a hydrazine-based chemical at 40°C as an etching solution is disclosed (for example, For example, refer to Patent Document 4). However, hydrazine is poisonous, and since it has a large influence on a human body and environmental load, it is unpreferable.

Moreover, the etching method using the etching liquid containing 15-45 mass % alkali metal hydroxide is disclosed (for example, refer patent document 5). In patent document 5, the etching liquid further containing an ethanolamine compound is also disclosed as a more preferable aspect. When the resin composition containing an alkali-insoluble resin, 20-40 mass % organic filler, and 30-50 mass % inorganic filler is etched using the etching liquid of patent document 5, the residue of the organic filler on the surface after etching Occasionally came out.

In addition, when the resin composition layer is etched with reference to the etching method disclosed in Patent Document 5, the opening diameter of the opening in the resin composition layer is Φ100 µm or less due to lack of affinity between the etchant and the resin composition layer. In the small-diameter opening process used as , an unetched point may occur. Therefore, the etching method in which an unetched point does not generate|occur|produce has been calculated|required.

Japanese Laid-Open Patent Publication No. 2003-101244 International Publication No. 2017/38713 pamphlet Japanese Patent Laid-Open No. 2008-300691 International Publication No. 2018/88345 pamphlet International Publication No. 2018/186362 pamphlet

The subject of this invention is providing the novel etching liquid suitable for the resin composition containing alkali-insoluble resin, an organic filler, and an inorganic filler, etc.

In the process of removing the resin composition containing the alkali-insoluble resin, the organic filler, and the inorganic filler using an etching solution, the resin composition (resin composition layer containing the resin composition) is efficiently removed (for example, residual It is another subject of this invention to provide the etching liquid of a resin composition and the etching method which can remove stably without water) and have high in-plane uniformity. Moreover, it is another subject of this invention to provide the etching method which can suppress generation|occurrence|production of an unetched spot even in the small-diameter opening process in which an opening diameter becomes phi 100 micrometers or less.

MEANS TO SOLVE THE PROBLEM The present inventors discovered that the said subject could be solved by the following means etc.

<1>

An etchant of a resin composition comprising an alkali-insoluble resin, 20 to 40% by mass of an organic filler and 30 to 50% by mass of an inorganic filler [etchant for resin composition, etchant for resin composition, resin composition layer (layer formed of resin composition) ) ), wherein the etching solution contains 15 to 45 mass% of an alkali metal hydroxide as a first component and 1 to 40 mass% of an ethanolamine compound as a second component, and an alcohol compound and a carbohydrate. An etching solution comprising at least one third component selected from acid compounds.

<2>

Etching liquid as described in <1> in which a 3rd component contains at least 1 sort(s) selected from a polyol compound, a polyhydric carboxylic acid compound, and a hydroxy acid compound.

<3>

Etching liquid as described in <1> or <2> in which a 3rd component contains a 3-60 mass % polyol compound.

<4>

Etching liquid as described in <2> or <3> whose molecular weight of the said polyol compound is 80 or more and 200 or less.

<5>

Etching liquid in any one of <2>-<4> in which the said polyol compound has 3 or more hydroxyl groups.

<6>

Etching liquid in any one of <2>-<5> in which the said polyol compound contains glycerol.

<7>

Etching liquid in any one of <1>-<6> in which a 3rd component contains a 2-20 mass % polyhydric carboxylic acid compound.

<8>

Etching liquid in any one of <1>-<7> in which a 3rd component contains a 2-20 mass % hydroxy acid compound.

<9>

The etching liquid as described in any one of <1>-<8> in which the said etching liquid contains 0.1-3 mass % aromatic alcohol compound.

<10>

Using the etching solution according to any one of <1> to <9>, an alkali-insoluble resin, 20 to 40 mass% of an organic filler, and 30 to 50 mass% of an inorganic filler having a step of etching a resin composition comprising: An etching method of a resin composition, characterized in that.

<11>

An etching step of etching a resin composition comprising an alkali-insoluble resin, 20 to 40 mass% of an organic filler, and 30 to 50 mass% of an inorganic filler using the etching solution according to any one of <1> to <9>; and an ultrasonic irradiation process of irradiating ultrasonic waves after the etching process.

<12>

The etching method of the resin composition as described in <10> or <11> which further has the process of pre-processing with the pretreatment liquid which consists of an acidic aqueous solution containing 2.5-7.5 mass % of anionic surfactant before an etching process.

<13>

It has a water washing process after an etching process, The etching method of the resin composition in any one of <10>-<12> whose time from the completion of an etching process to the start of a water washing process is less than 30 seconds.

<14>

Etching process WHEREIN: Etching resist is used, The etching method of the resin composition in any one of <10>-<13> whose etching resist is a metal mask or a dry film resist.

ADVANTAGE OF THE INVENTION According to this invention, the novel etching liquid suitable for the resin composition containing alkali-insoluble resin, an organic filler, and an inorganic filler, etc. can be provided.

Moreover, according to this invention, in the process of removing the resin composition containing an alkali-insoluble resin, an organic filler, and an inorganic filler using an etching liquid, the resin composition (resin composition layer which consists of the resin composition containing this resin composition) efficiently It is possible to provide an etchant and an etching method for a resin composition that can be removed (eg, stably removed without residue) and have high in-plane uniformity. Further, according to the present invention, it is possible to provide an etching method capable of suppressing the occurrence of unetched spots even in the small-diameter opening treatment in which the opening diameter becomes Φ100 µm or less.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic cross-sectional structural diagram of a soldering resist pattern.
It is a schematic cross-sectional structural diagram of a soldering resist pattern.
3 : is sectional process drawing which showed an example of the process of etching the resin composition layer 4 by the etching method of this invention.

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated. In addition, in this specification, "etching liquid of a resin composition" may be abbreviated as "etching liquid", and "etching method of a resin composition" may be abbreviated as "etching method" in some cases.

The etching solution of the present invention comprises, for example, a resin composition comprising an alkali-insoluble resin, an organic filler and an inorganic filler (in particular, an alkali-insoluble resin, 20 to 40 mass% of an organic filler and 30 to 50 mass% of an inorganic filler It is used for processing to remove the resin composition). Moreover, the etching method of this invention uses the etching liquid of this invention, and uses the resin composition (particularly, alkali insoluble resin, 20-40 mass % of organic filler, and 30-50 of an alkali-insoluble resin, an organic filler, and an inorganic filler) It is characterized by having an etching process which etches the resin composition containing mass % of inorganic filler).

<Etching liquid>

The etchant of the present invention is a resin composition comprising an alkali-insoluble resin, an organic filler and an inorganic filler (in particular, a resin composition comprising an alkali-insoluble resin, 20 to 40 mass% of an organic filler, and 30 to 50 mass% of an inorganic filler) of the etching liquid (etching liquid for resin compositions, liquid for etching the resin composition).

The etching liquid of this invention contains the alkali metal hydroxide (particularly, 15-45 mass % alkali metal hydroxide) as a 1st component normally. Since the alkali-insoluble resin has a property of not being dissolved in an aqueous alkali solution, it cannot be originally removed by an aqueous alkali solution. However, the resin composition containing alkali-insoluble resin can be removed by using the etching liquid of this invention. This is because the inorganic filler in the highly filled resin composition, ie, the inorganic filler filled in the resin composition with a high content of 30-50 mass %, is dissolved and dispersed by the etching liquid containing a high concentration alkali metal hydroxide. In addition, when the alkali-insoluble resin and the organic filler filled with a high content of 20 to 40 mass% are swollen by the etching solution, the difference in the expansion coefficient of the alkali-insoluble resin and the organic filler occurs, so that the structure of the resin composition becomes brittle. , it is presumed to be because the progress of the etching is accelerated.

When the content of alkali metal hydroxide (ratio with respect to the entire etching solution, hereinafter the same in the same expression) is 15 mass% or more, the solubility of the inorganic filler is excellent, and when the content of alkali metal hydroxide is 45 mass% or less, alkali metal hydroxide Since the precipitation of the liquid does not occur easily, the stability of the liquid over time is excellent. Content of an alkali metal hydroxide becomes like this. More preferably, it is 20-45 mass %.

As said alkali metal hydroxide, at least 1 sort(s) of compound chosen from the group of potassium hydroxide, sodium hydroxide, and lithium hydroxide is used suitably. As an alkali metal hydroxide, you may use individually by 1 type among these, and may use it in combination of 2 or more type.

The etching liquid of this invention contains the alkanolamine compound (usually an ethanolamine compound, especially an ethanolamine compound of 1-40 mass %) as a 2nd component normally. When an etching liquid contains an ethanolamine compound etc., an ethanolamine compound etc. can permeate in a resin composition, it can make a resin composition swell, and can melt|dissolve an inorganic filler uniformly. When the content of the alkanolamine compound (eg, ethanolamine compound) is 1 mass % or more, the swelling property of the alkali-insoluble resin is excellent, and when it is 40 mass % or less, compatibility with water is increased, and phase separation does not occur easily and excellent stability over time. Content of an alkanolamine compound (for example, an ethanolamine compound) becomes like this. More preferably, it is 3-35 mass %.

The alkanolamine compound (eg, ethanolamine compound) may be any type such as primary amine, secondary amine, or tertiary amine, and may be used alone or in combination of two or more types. You may use it. As an example of a typical amine compound, 2-aminoethanol which is a primary amine; 2-(2-aminoethylamino)ethanol, which is a mixture of a primary amine and a secondary amine (ie, a compound having a primary amino group and a secondary amino group in one molecule); 2-(methylamino)ethanol and 2-(ethylamino)ethanol which are secondary amines; 2,2'-methyliminodiethanol which is a tertiary amine, 2-(dimethylamino) ethanol, etc. are mentioned. Among them, 2-(methylamino)ethanol and 2-(2-aminoethylamino)ethanol are more preferable.

The etching liquid of this invention contains the at least 1 sort(s) of 3rd component chosen from an alcohol compound and a carboxylic acid compound. In particular, the etching liquid of this invention may contain a 3-60 mass % polyol compound, a 2-20 mass % polyhydric carboxylic acid compound, or a 2-20 mass % hydroxy acid compound as a 3rd component. When the etching solution of the present invention contains such a third component (for example, a polyol compound, a polyhydric carboxylic acid compound and/or a hydroxy acid compound), the alkali-insoluble resin, the organic filler, and the dissolved inorganic filler are simultaneously dispersed and removed. can do.

Although it is only guess about the mechanism of this effect, it is thought that it relates to the dissolution dispersion removal mechanism of the etching liquid of this invention mentioned above. In order to stably remove the resin composition by etching, some or all of the inorganic filler highly filled in the resin composition is dissolved with an etching solution containing a high concentration of alkali metal hydroxide, and the film shape as a resin composition cannot be maintained at a stage, It is necessary to simultaneously remove the alkali-insoluble resin, the organic filler and the dissolved inorganic filler. When any one of the removal proceeds, the remaining components become residues and remain on the surface after etching. When the etchant contains a third component (for example, a polyol compound, a polyhydric carboxylic acid compound, and/or a hydroxy acid compound), it has a function of arranging the components that cannot maintain the film shape, and at the same time improves the removal performance. I think it is improving. It is thought that the margin of the processing time which does not leave a residue increases by the effect, and the resin composition containing alkali-insoluble resin, an organic filler, and an inorganic filler can be removed stably.

Although the content of the third component (total content when two or more is combined) varies depending on the components constituting the third component, for example, 0.1 mass% or more, 0.5 mass% or more, preferably 1 mass% or more , More preferably 1.5 mass % or more, especially 2 mass % or more may be sufficient.

In addition, the content of the third component varies depending on the components constituting the third component, but may be, for example, 60 mass% or less, 50 mass% or less, 40 mass% or less, 30 mass% or less, 20 mass% or less. do.

[alcohol compound]

Alcohol compounds [alcohol compounds other than alkanolamine compounds (ethanolamine compounds)] include monoalcohol compounds [eg, alkanols (eg, ethanol, propanol, butanol, pentanol, hexanol, etc.), alicyclic non-aromatic monool compounds such as monools (eg, cyclohexanol) (aliphatic monools)], polyol compounds, and the like.

An alcohol compound may be used individually by 1 type, and may be used in combination of 2 or more type.

The alcohol compound may contain the polyol compound preferably.

In addition, the alcohol compound may be an aromatic alcohol compound [a aromatic alcohol compound (for example, benzyl alcohol, phenoxyethanol, etc.) described later] or a non-aromatic alcohol compound (a non-aromatic monool compound, a non-aromatic polyol compound). and may include both of these.

In addition, any of a saturated and unsaturated compound may be sufficient as a non-aromatic alcohol compound.

Typically, the alcohol compound contains at least a non-aromatic alcohol compound (particularly, a non-aromatic polyol compound) in many cases. In addition, as mentioned later, you may combine an aromatic alcohol compound suitably with a 3rd component (further, a 1st component and a 2nd component).

When the third component contains an alcohol compound, the content of the alcohol compound varies depending on the total content of the third component, for example, 0.1 mass% or more, 0.5 mass% or more, preferably 1 mass% or more, more Preferably, 2 mass % or more may be sufficient, and 3 mass % or more may be especially sufficient. Moreover, content of an alcohol compound may be 60 mass % or less, 50 mass % or less, 40 mass % or less, for example.

When the third component is composed of an alcohol compound, if the content of the alcohol compound (eg, polyol compound) used in the etching solution of the present invention is small (eg, less than 3% by mass), the performance of collecting and dispersing into one When this becomes insufficient and there is too much (for example, it exceeds 60 mass %), it may gather together too much and removability may become inadequate. Therefore, the content of the alcohol compound (eg, polyol compound) varies depending on the total content of the third component, etc. mass %.

A preferable molecular weight range exists in the polyol compound used for the etching liquid of this invention, and 80 or more and 200 or less are preferable. Moreover, as a polyol compound, the compound which has 3 or more hydroxyl groups is preferable.

Moreover, as a preferable polyol compound, the compound which exists in a comparatively densely dense hydroxyl group is mentioned. In such a polyol compound, the molecular weight per hydroxyl group may be, for example, 100 or less, 80 or less, 60 or less, 50 or less, 40 or less, 35 or less.

Although either an aliphatic polyol compound and an aromatic polyol compound may be sufficient as a polyol compound, It is especially preferable to use at least an aliphatic polyol compound (alkane polyol etc.). In addition, sugar or sugar alcohol may be sufficient as a polyol compound.

As a specific example, a polyol having 3 or more hydroxyl groups [eg, alkanetriol (eg, C _3-10 alkanetriol such as glycerin, trimethylolpropane), alkanetetraol (eg, , erythritol, C _4-12 alkanetetraols such as pentaerythritol), alkanepolyols having 5 or more hydroxyl groups (eg, sorbitol, xylitol, bolemitol, etc.), having 3 or more hydroxyl groups Polymers of polyols (eg, diglycerin, dipentaerythritol), etc.], diols [eg, poly(alkanediol) [eg, poly C _2-6 such as diethylene glycol, dipropylene glycol, etc.] alkanediol], alkanediol (For example, _C2-10 alkanediol, such as ethylene glycol, propylene glycol, butanediol), etc.] are mentioned. Among these, glycerol is especially preferable. Moreover, as a polyol compound, you may use individually by 1 type, and may use it in combination of 2 or more type.

[Carboxylic acid compound]

Carboxylic acid, a carboxylic acid derivative (for example, carboxylate), etc. are contained as a carboxylic acid compound (it may simply be called "carboxylic acid"). In addition, a hydrate etc. may be sufficient as a carboxylic acid compound (carboxylic acid, carboxylate, etc.).

As carboxylic acid, monocarboxylic acid (monohydric carboxylic acid), polyhydric carboxylic acid (polyhydric carboxylic acid mentioned later, etc.), hydroxy acid (hydroxy acid mentioned later, etc.) etc. are mentioned, for example. can

Examples of the monocarboxylic acid include fatty acids [eg, alkanoic acids such as formic acid, acetic acid and propionic acid (eg, C _1-10 alkanoic acid)].

Further, the carboxylic acid may be an amino acid (aminocarboxylic acid).

The salt is not particularly limited, and for example, a metal salt [eg, an alkali metal salt (eg, a lithium salt, a sodium salt, a potassium salt, etc.), an alkaline earth metal salt (eg, a magnesium salt, a calcium salt) etc.), zinc salt, etc.], an amine salt, an ammonium salt, etc. are mentioned.

A carboxylic acid compound may be used individually by 1 type, and may be used in combination of 2 or more type.

A polyhydric carboxylic acid compound and a hydroxy acid compound are contained in a preferable carboxylic acid compound. Therefore, the carboxylic acid compound may contain at least 1 type selected from a polyhydric carboxylic acid compound and a hydroxy acid compound.

When the third component contains a carboxylic acid compound, the content of the carboxylic acid compound varies depending on the total content of the third component, for example, 0.1 mass% or more, 0.5 mass% or more, preferably 1 mass% % or more, more preferably 1.5 mass% or more, and especially 2 mass% or more. Moreover, 50 mass % or less, 40 mass % or less, 30 mass % or less, 20 mass % or less may be sufficient as content of a carboxylic compound, for example.

(polyhydric carboxylic acid compound)

In the case where the third component is composed of a polyhydric carboxylic acid compound, if the content of the polyhydric carboxylic acid compound used in the etching solution of the present invention is small (for example, less than 2 mass%), the performance of collecting and dispersing into one is insufficient. If it becomes too much (for example, it exceeds 20 mass %), it may gather into one too much, and removability may become inadequate. Therefore, although content of a polyhydric carboxylic acid compound changes with the total content of a 3rd component, etc., it is preferable to select within the range which can implement|achieve removability efficiently, More preferably, it is 3-15 mass %. As above-mentioned in polyhydric carboxylic acid (polyhydric carboxylic acid compound) used for the etching liquid of this invention, the derivative (for example, salt etc.) and hydrate of polyhydric carboxylic acid are also contained.

Any of aliphatic polyhydric carboxylic acid and aromatic polyhydric carboxylic acid may be sufficient as polyhydric carboxylic acid, and aliphatic polyhydric carboxylic acid may be used suitably typically. Any of saturated and unsaturated fatty acids may be sufficient as such an aliphatic polyhydric carboxylic acid.

Polyhydric carboxylic acid WHEREIN: The number of carboxyl groups should just be 2 or more, for example, 2-10 (for example, 2-6) etc. may be sufficient.

Preferred polyhydric carboxylic acids include compounds in which carboxyl groups are relatively densely present. Such polyhydric carboxylic acid WHEREIN: The molecular weight per carboxyl group may be 100 or less, 80 or less, 60 or less, 50 or less, 40 or less, 35 or less, for example.

As polyhydric carboxylic acid (polyhydric carboxylic acid compound) used for the etching liquid of this invention, For example, C2 _- C2-, such as an alkane polycarboxylic acid (For example, oxalic acid, malonic acid, succinic acid, glutaric acid, etc.) ₁₂ alkanedioic acid), alkenepolycarboxylic acids (eg, C _4-12 alkenedicarboxylic acids such as maleic acid and fumaric acid), carboxyalkylamines [eg, nitrilotriacetic acid (NTA), ethylenediamine tetraacetic acid (EDTA), L-aspartic acid-N,N-2acetic acid (ADSA), diethylenetriaminepentaacetic acid (DTPA)] and derivatives thereof (salts and the like) are exemplified. Among these polyhydric carboxylic acids (polyhydric carboxylic acid compounds), malonic acid, maleic acid, ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA) and salts thereof, etc. are alkali-insoluble resins, organic fillers and inorganic In the process of removing the resin composition containing the filler, it is more preferable in order to remove the resin composition layer containing the resin composition stably without any residue, and malonic acid, ethylenediaminetetraacetic acid (EDTA) and these A salt is more preferable, and ethylenediaminetetraacetic acid (EDTA) and a salt thereof are particularly preferable. Moreover, as polyhydric carboxylic acid (polyhydric carboxylic acid compound), you may use individually by 1 type, and may use it in combination of 2 or more type.

(hydroxy acid compound)

When the third component is composed of a hydroxy acid compound, if the content of the hydroxy acid compound used in the etching solution of the present invention is small (for example, less than 2 mass%), the performance of collecting and dispersing into one becomes insufficient, When it is large (for example, it exceeds 20 mass %), it may gather together too much and removability may become inadequate. Therefore, although content of a hydroxy acid compound changes with the total content of a 3rd component, etc., it is preferable to select within the range which can implement|achieve removability efficiently, More preferably, it is 3-15 mass %. As mentioned above, the hydroxy acid (hydroxy acid compound) used for the etching liquid of this invention also contains the derivative (for example, salt etc.) of a hydroxy acid. Moreover, as mentioned above, a hydrate may be sufficient as a hydroxy acid, its salt, etc.

The hydroxy acid may be either an aliphatic hydroxy acid or an aromatic hydroxy acid, and the aliphatic hydroxy acid may be either a saturated or unsaturated fatty acid.

In a hydroxy acid, the number of hydroxyl groups should just be 1 or more, for example, 1-10 (for example, 1-5), etc. may be sufficient.

In a hydroxy acid, the number of carboxyl groups should just be 1 or more, for example, 1-10 (for example, 1-5) etc. may be sufficient.

Preferred hydroxy acids include compounds in which hydroxy groups and carboxy groups are relatively densely present. In such a hydroxy acid, the molecular weight per total amount of a hydroxyl group and a carboxyl group may be 100 or less, 80 or less, 60 or less, 50 or less, 40 or less, 35 or less, for example.

As the hydroxy acid (hydroxy acid compound) used in the etching solution of the present invention, an aliphatic hydroxy acid [for example, a hydroxyalkanecarboxylic acid (for example, glycolic acid, lactic acid, tartronic acid, glyceric acid, Leucic acid, malic acid, tartaric acid, gluconic acid, citric acid, isocitric acid, mevalonic acid, pantoic acid, hydroxypentanoic acid, hydroxyhexanoic acid, etc.), hydroxyalkyl-carboxyalkylamines (e.g., hydroxyethylimino diacetic acid, hydroxyiminodisuccinic acid, etc.), alicyclic hydroxy acids (eg, quinic acid), etc.], aromatic hydroxy acids [eg, salicylic acid, 4-hydroxyphthalic acid, 4-hydroxyisophthalic acid, Creosotic acid (homosalicylic acid, hydroxy(methyl)benzoic acid), vanillic acid, syringic acid, resorcylic acid, protocatechuic acid, gentic acid, orceline acid, gallic acid, mandelic acid, atrolactic acid, melilotic acid, floretic acid , coumaric acid, umbellic acid, caffeic acid, etc.], and derivatives thereof (eg, salts and the like) are exemplified. Among these hydroxy acids (hydroxy acid compounds), malic acid, tartaric acid, gallic acid, 4-hydroxyisophthalic acid and their salts are alkali-insoluble resins, organic fillers and inorganic fillers. In order to remove the resin composition layer which consists of a resin composition stably without a residue, it is more preferable, tartaric acid and 4-hydroxyphthalic acid and their salts are still more preferable, and especially tartaric acid and its salt are preferable. Moreover, as a hydroxy acid, you may use individually by 1 type, and may use it in combination of 2 or more type.

(aromatic alcohol compounds)

The etching liquid may contain the aromatic alcohol compound. In addition, although an aromatic alcohol compound corresponds to the said alcohol compound (that is, 3rd component), especially, another 3rd component [for example, a non-aromatic alcohol compound (polyol compound, etc.), a carboxylic acid compound (polyhydric carboxyl compound) acid compound, hydroxy acid compound, etc.) and the like] (used as the fourth component) is preferred.

Specifically, it is preferable that the etching liquid of this invention contains the aromatic alcohol compound (For example, 0.1-3 mass % of aromatic alcohol compound) as a 4th component. When the etching liquid of this invention contains an aromatic alcohol compound, the effect which disperse|distributes and removes alkali-insoluble resin, an organic filler, and the dissolved inorganic filler simultaneously becomes high. Therefore, in the <etching method> mentioned later, even if it does not implement an ultrasonic irradiation process, the resin composition layer can be removed without a residue. Of course, you may implement the etching method of this invention which has an ultrasonic irradiation process using the etching liquid containing aromatic alcohol as a 4th component.

Although it is only guess about the mechanism of this effect, it is thought that it relates to the dissolution dispersion removal mechanism of the etching liquid of this invention mentioned above. In order to stably remove the resin composition by etching, some or all of the inorganic filler highly filled in the resin composition is dissolved with an etching solution containing a high concentration of alkali metal hydroxide, and the film shape as a resin composition cannot be maintained at a stage, It is necessary to simultaneously remove the alkali-insoluble resin, the organic filler and the dissolved inorganic filler. When any one of the removal proceeds, the remaining components become residues and remain on the surface after etching. When the etching solution contains another third component (for example, a polyol compound, a polyhydric carboxylic acid compound, and/or a hydroxy acid compound, etc.), it has a function of arranging the components that cannot maintain the film shape, and simultaneously removes them It is thought to improve performance. And it is thought that the performance which removes the alkali-insoluble resin and organic filler which are not melt|dissolved is being improved because etching liquid contains an aromatic alcohol compound further. It is thought that the margin of the processing time which does not leave a residue increases by the effect, and the resin composition containing alkali-insoluble resin, an organic filler, and an inorganic filler can be removed stably.

In the case of using an aromatic alcohol compound, the content of the aromatic alcohol compound varies depending on the total content of the third component, etc., but may be, for example, 0.1 mass% or more, 0.5 mass% or more, and 20 mass% or less, 10 mass% Hereinafter, 5 mass % or less, 3 mass % or less, etc. may be sufficient.

If the content of the aromatic alcohol compound used in the etching solution of the present invention is, for example, about 0.1 mass% or more, the performance of removing the alkali-insoluble resin and organic filler is excellent, and if it is less than 3 mass%, compatibility with water The property is improved, the phase separation is less likely to occur, and the stability over time and the treatment uniformity are excellent. Content of an aromatic alcohol compound becomes like this. More preferably, it is 0.5-2.5 mass %.

As the aromatic alcohol compound used in the etching solution of the present invention, for example, aralkyl alcohol (eg, benzyl alcohol, 4-methylbenzyl alcohol, 3-methylbenzyl alcohol, 2-methylbenzyl alcohol, 2-phenylethanol , 3-phenylpropanol, 1-phenyl-1-propanol, 1-phenyl-2-propanol, 4-phenyl-1-butanol, 4-phenyl-2-butanol, 1-phenyl-2-butanol, 2-phenyl- 2-butanol, etc.), (poly) alkanediol monoaryl ether (eg, 2-phenoxyethanol, phenyl diglycol, phenyl propylene glycol, phenyl dipropylene glycol, etc.), (poly) alkanediol mono aralkyl ether ( For example, benzyl glycol, benzyl di glycol, etc.) etc. are illustrated. Among these aromatic alcohols, in the process of removing the resin composition containing the alkali-insoluble resin, the organic filler and the inorganic filler, in order to stably remove the resin composition layer containing the resin composition without residue, benzyl alcohol and 2-phenoxyethanol is more preferable, and 2-phenoxyethanol is especially preferable. Moreover, aromatic alcohol may be used individually by 1 type, and may be used in combination of 2 or more type.

A coupling agent, a leveling agent, a coloring agent, surfactant, an antifoamer, an organic solvent, etc. can also be added suitably to the etching liquid of this invention as needed. As an organic solvent, Ketones, such as acetone, methyl ethyl ketone, and cyclohexanone; acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitols such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; Amide solvents, such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone, etc. are mentioned.

It is preferable that the etching liquid of this invention is aqueous alkali solution. As water used for the etching liquid of this invention, tap water, industrial water, pure water, etc. can be used. Of these, it is preferable to use pure water. In the present invention, pure water generally used for industrial purposes can be used.

<Pretreatment solution>

The pretreatment liquid which concerns on this invention is an acidic aqueous solution containing 2.5-7.5 mass % of anionic surfactant, for example. Examples of the anionic surfactant contained in the pretreatment solution according to the present invention include lauryl sulfate, polyoxyethylene alkyl ether sulfate, polyoxyalkylene alkenyl ether sulfate, alkylbenzenesulfonate, dodecylbenzenesulfonate, alkylnaphthalenesulfonate, dialkyl sulfosuccinate, alkyl diphenyl ether disulfonate, alkane sulfonate, alkenyl succinate, and the like. Among these anionic surfactants, polyoxyethylene alkyl ether sulfate and alkyl naphthalene sulfonate are preferable in order to suppress the occurrence of unetched spots even in small-diameter opening treatment in which the opening diameter of the opening in the resin composition layer is Φ100 µm or less. and an alkyl naphthalene sulfonate is particularly preferable. As the counter ion, alkali metal ions and alkanolamine salt ions are preferable. Moreover, these anionic surfactant may be used individually by 1 type, and may be used in combination of 2 or more type.

Even in the small-diameter opening treatment in which the opening diameter of the opening in the resin composition layer becomes Φ100 µm or less, in order to suppress the occurrence of unetched spots, the content of the anionic surfactant contained in the pretreatment solution is preferably 2.5% by mass or more, , more preferably 3 mass% or more. In addition, the effect obtained does not increase, it is uneconomical, and it takes time to wash with water after pretreatment, and when water washing is insufficient, aggregation of the anionic surfactant may lead to generation of unetched spots, etc. From a viewpoint, it is preferable that it is 7.5 mass % or less, and it is more preferable that it is 6 mass % or less.

The pretreatment liquid according to the present invention is acidic, and from the viewpoint of suppressing the occurrence of unetched spots even in the small-diameter opening treatment in which the opening diameter of the opening in the resin composition layer becomes Φ100 µm or less, the pH is preferably 6 or less. Moreover, it is preferable that pH is 1 or more from viewpoints, such as the effect obtained does not increase, it is uneconomical, and it takes time for mixing of a pH adjuster. As the pH adjusting agent, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, hydroxide salts, carbonates, and the like can be used. Moreover, the pretreatment liquid which concerns on this invention may contain well-known additives, such as an antifoamer, a foam inhibitor, a thickener, and an antiseptic|preservative.

As water used for the pretreatment liquid according to the present invention, tap water, industrial water, pure water, etc. can be used. Of these, it is preferable to use pure water. In the present invention, pure water generally used for industrial purposes can be used.

<Resin composition>

The resin composition which concerns on this invention is a resin composition containing alkali-insoluble resin, an organic filler, and an inorganic filler. Content of the organic filler in the resin composition is 20-40 mass % with respect to 100 mass % of non-volatile matter in a resin composition, for example. When content of an organic filler is less than 20 mass %, the influence by the difference of the expansion coefficient which generate|occur|produces with the etching liquid containing an alkali metal hydroxide with respect to the whole resin composition becomes small, and etching does not advance. When content of an organic filler exceeds 40 mass %, it exists in the tendency for flexibility to fall by the fluid fall of a resin composition, and it may be inferior to practicality.

Content of an inorganic filler is 30-50 mass % with respect to 100 mass % of non-volatile matter in a resin composition, for example. When content of an inorganic filler is less than 30 mass %, since there are too few inorganic fillers as a site melt|dissolved with the etching liquid containing an alkali metal hydroxide with respect to the whole resin composition, etching may not advance. When content of an inorganic filler exceeds 50 mass %, it exists in the tendency for flexibility to fall by the fluidity|liquidity fall of a resin composition, and it may be inferior to practicality.

In the present invention, organic fillers include, for example, polytetrafluoroethylene (PTFE), fluorinated ethylene-propylene copolymer (FEP), perfluoroalkoxy polymer (PFA), chlorotrifluoroethylene (CTFE) , tetrafluoroethylene-chlorotrifluoroethylene copolymer (TFE/CTFE), ethylene-chlorotrifluoroethylene copolymer (ECTFE), at least one selected from the group consisting of polychlorotrifluoroethylene (PCTFE) of fluorine-based resins. These resins may be used individually by 1 type, and may be used in combination of 2 or more type. From the viewpoint of lowering the dielectric constant of the resin composition layer, PTFE is preferable.

In the present invention, examples of the inorganic filler include silicates such as silica, glass, clay, and mica; oxides such as alumina, magnesium oxide, titanium oxide, and silica; carbonates such as magnesium carbonate and calcium carbonate; hydroxides such as aluminum hydroxide, magnesium hydroxide, and calcium hydroxide; Sulfates, such as barium sulfate and calcium sulfate, etc. are mentioned. Moreover, as an inorganic filler, aluminum borate, aluminum nitride, boron nitride, strontium titanate, barium titanate, etc. are mentioned further. Of these, at least one compound selected from the group consisting of silica, glass, clay and aluminum hydroxide is more preferably used because it dissolves in an aqueous solution containing an alkali metal hydroxide. Silica is more preferable at the point excellent in low thermal expansion property, and spherical fused silica is especially preferable. As an inorganic filler, 1 type in these may be used independently and may be used in combination of 2 or more type.

Alkali-insoluble resin in this invention is demonstrated. Alkali-insoluble resin is not specifically limited except the property that it does not melt|dissolve with respect to aqueous alkali solution. Specifically, it is a resin having a very small content of a carboxyl group-containing resin and the like required to dissolve in an aqueous alkali solution, and it is preferable that the acid value (JIS K2501: 2003) as an index of the content of free carboxyl groups in the resin is less than 40 mgKOH/g Do. More specifically, the alkali-insoluble resin is, for example, a resin containing an epoxy resin and a thermosetting agent for curing the epoxy resin. Examples of the aqueous alkali solution include an aqueous solution containing an inorganic alkaline compound such as alkali metal silicate, alkali metal hydroxide, alkali metal phosphate, alkali metal carbonate, ammonium phosphate, ammonium carbonate, monoethanolamine, diethanolamine, triethanolamine, methylamine, Dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, cyclohexylamine, tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, trimethyl-2-hydroxyethylammonium hydroxide ( an aqueous solution containing an organic alkaline compound such as choline).

As an epoxy resin, For example, bisphenol-type epoxy resins, such as a bisphenol A epoxy resin, a bisphenol F-type epoxy resin, and a bisphenol S-type epoxy resin; Novolak-type epoxy resins, such as a phenol novolak-type epoxy resin and a cresol novolak-type epoxy resin, etc. are mentioned. Moreover, as an epoxy resin, a biphenyl type epoxy resin, a naphthalene type epoxy resin, anthracene type epoxy resin, a phenoxy type epoxy resin, a fluorene type epoxy resin, etc. are mentioned further. As an epoxy resin, you may use individually by 1 type in these, and may use it in combination of 2 or more type.

The thermosetting agent is not particularly limited as long as it has a function of curing the epoxy resin, and preferable examples thereof include a phenol-based curing agent, a naphthol-based curing agent, an active ester-based curing agent, a benzoxazine-based curing agent, and a cyanate ester resin. . As a thermosetting agent, 1 type in these may be used independently and may be used in combination of 2 or more type.

In addition to the thermal curing agent, it may further contain a curing accelerator. As a hardening accelerator, an organic phosphine compound, an organic phosphonium salt compound, an imidazole compound, an amine adduct compound, a tertiary amine compound, etc. are mentioned, for example. As a hardening accelerator, 1 type in these may be used independently and may be used in combination of 2 or more type. Moreover, when using cyanate ester resin as a thermosetting agent, in order to shorten hardening time, you may add the organometallic compound currently used as a hardening catalyst. Examples of the organometallic compound include an organocopper compound, an organozinc compound, and an organocobalt compound.

The resin composition containing an alkali-insoluble resin, an organic filler, and an inorganic filler can form an insulating resin composition layer by thermosetting, However, Etching using the etching liquid of this invention is A stage (of a hardening reaction) normally. before initiation) or in the B-stage (intermediate stage of the curing reaction). Even in the A stage or B stage, the alkali-insoluble resin is not dissolved in the etching solution of the present invention, but the inorganic filler is partially or completely dissolved by the etching solution of the present invention, and the expansion rate of the alkali-insoluble resin and the organic filler to the etching solution With the difference, dispersion and removal of the resin composition proceeds. It becomes C stage, and in the state which resin fully hardened|cured, it may become difficult for the etching liquid of this invention to swell a resin composition layer, and to permeate into a resin composition layer, and uniform etching may become difficult.

As thermosetting conditions from A stage to B stage, Preferably it is 10-60 minutes at 100-160 degreeC, More preferably, although it is 10-60 minutes at 100-130 degreeC, it is not limited to this. When it heats at high temperature exceeding 160 degreeC, thermosetting further advances and the etching process using the etching liquid of this invention may become difficult.

<Etching method>

Below, the etching method of this invention is demonstrated. 3 : is a cross-sectional process drawing which showed an example of the process of etching the resin composition layer 4 by the etching method of this invention. In this etching method, a part or all of the solder connection pads 3 on a circuit board exposed from the resin composition layer 4 can form the soldering resist pattern.

In step (I), a conductor pattern is formed by patterning the copper foil 3' on the surface of the copper clad laminate 1' which consists of the insulating layer 2 and the copper foil 3', and a solder connection pad 3 A circuit board 1 having

At a process (II), in the surface of the circuit board 1, the resin composition layer 4 with the copper foil 6 is formed so that the whole surface may be covered.

At a process (III), the copper foil 6 on the resin composition layer 4 is patterned, and the metal mask 5 is formed as the etching resist 5. The copper foil 3' and the copper foil 6 can be patterned by the copper etching process using a ferric chloride liquid, cupric chloride liquid, etc., for example.

After the step (III), in the step (IV), in the etching step, through the etching resist 5, the etchant of the resin composition layer until a part or all of the solder connection pad 3 is exposed , the resin composition layer 4 is etched.

In addition, after the step (III), in the step (IV), the affinity of the etching solution and the resin composition layer 4 is improved by the pretreatment step of bringing the pretreatment solution into contact with the resin composition layer 4 and the etching resist 5 . After improving, in an etching process, the resin composition layer 4 is etched through the etching resist 5 until a part or all of the solder connection pads 3 are exposed with the etching liquid for resin composition layers. can also be processed.

In the step (IV)-2, the resin residue 8 is removed in the water washing step following the etching treatment.

In step (IV)-2, the resin residue 8 can also be removed by irradiating ultrasonic waves in the water washing step following the etching step.

At a process (V), the etching resist 5 (metal mask) is removed by an etching, and a part or all of the solder connection pads 3 form the soldering resist pattern exposed from the resin composition layer 4 .

In the present invention, the pretreatment time is not particularly limited, but even in the small-diameter opening treatment in which the opening diameter of the opening in the resin composition layer becomes Φ100 µm or less, in order to suppress the occurrence of unetched spots, it is preferably 1 minute or longer, , more preferably 3 minutes or longer. The pretreatment time is preferably 10 minutes or less. Although the temperature of the pretreatment liquid according to the present invention is not particularly limited, in order to suppress the occurrence of unetched spots even in the small-diameter opening treatment in which the opening diameter of the opening in the resin composition layer becomes Φ100 µm or less, it is preferably 10°C or higher. And it is more preferable that it is 30 degreeC or more. The temperature of the pretreatment solution is preferably 70° C. or less.

In the etching method of this invention, the temperature of etching liquid becomes like this. Preferably it is 60-90 degreeC. The optimum temperature varies depending on the type of the resin composition, the thickness of the resin composition layer containing the resin composition, the shape of a pattern obtained by processing to remove the resin composition, etc., but the temperature of the etchant is more preferably 60 to 85 °C, more preferably 70 to 85 °C.

In the etching method of this invention, while part or all of the inorganic filler filled with high content melt|dissolves gradually from the surface layer of a resin composition layer, alkali-insoluble resin and organic filler disperse|distribute, and removal of a resin composition layer advances.

The etching method of this invention WHEREIN: Methods, such as an immersion process, a paddle process, a spray process, brushing, scraping, can be used for a pre-processing process and an etching process. Among these, the point of the uniformity of an etching process to an immersion process is preferable.

In the etching method of this invention, after removing a resin composition by an etching process, while washing|cleaning the etching liquid which adheres remaining on the surface of the resin composition, it adheres to the surface of the connection pad 3 and the wall surface of the resin composition layer 4 In order to remove the used resin residue 8, it is preferable to implement a water washing process. It is preferable that a water washing process is an ultrasonic irradiation process which irradiates an ultrasonic wave. It is preferable to perform ultrasonic irradiation by an immersion system. In ultrasonic irradiation, preferably, the resin residue 8 adhering to the surface of the connection pad 3 and the wall surface of the resin composition layer 4 is brought into contact with water subjected to ultrasonic vibration of 20 to 150 kHz for 10 to 300 seconds. it is preferable Here, when the frequency of ultrasonic vibration is less than 20 kHz or exceeds 150 kHz, since a special apparatus is required and there is no great merit, 20-150 kHz is preferable as for the frequency of ultrasonic vibration.

In addition, when the time (contact time) for contacting the resin residue 8 adhering to the surface of the connection pad 3 and the wall surface of the resin composition layer 4 to water subjected to ultrasonic vibration is less than 10 seconds, the resin residue ( 8) may not be sufficiently removed. When contact time exceeds 300 second, time may become too long and productivity may fall. Accordingly, the contact time is preferably 10 to 300 seconds. In addition, in order to wash out the water washing water in which the organic filler is dispersed in the water washing process by ultrasonic irradiation, it is preferable to combine the water washing process of a spray system after the water washing process by ultrasonic irradiation of an immersion system. As for the spray pressure, 0.02-0.3 Mpa is preferable.

As water washing water, tap water, industrial water, pure water, etc. can be used. Of these, it is preferable to use pure water. As pure water, what is generally used for an industrial use can be used. Moreover, it is preferable that the temperature of water washing water is below the temperature of etching liquid, and it is preferable that the temperature difference of etching liquid and water washing water is 40-50 degreeC.

Etching process WHEREIN: When using the etching resist 5, as the etching resist 5, other than the metal mask mentioned above, a dry film resist pattern can be used.

The dry film resist according to the present invention contains at least a photocrosslinkable resin composition, is coated with a photocrosslinkable resin on a carrier film such as polyester, to form a photocrosslinkable resin layer, and in some cases polyethylene or the like It has a structure which coat|covered the photocrosslinkable resin layer top with the protective film. The photocrosslinkable resin layer contains, for example, a binder polymer containing a carboxyl group, a photopolymerizable compound having at least one polymerizable ethylenically unsaturated group in the molecule, a photopolymerization initiator, a solvent, and other additives. Their blending ratio is determined by the balance of properties required, such as sensitivity, resolution, and degree of crosslinking. Examples of the photo-crosslinkable resin composition are "Photopolymer Handbook" (Photopolymer Conference Edition, 1989, published by the Industrial Research Society, Ltd.) or "Photopolymer Technology" (Akio Yamamoto, Edited by Motaro Nagamatsu, 1988) publication, Nikkan Kogyo Shimbun, etc.), and a desired photocrosslinkable resin composition can be used. It is preferable that it is 15-100 micrometers, and, as for the thickness of a photocrosslinkable resin layer, it is more preferable that it is 20-50 micrometers.

As the exposure method of the dry film resist according to the present invention, reflective image exposure using a xenon lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, an ultra-high pressure mercury lamp, or a UV fluorescent lamp as a light source, single-sided and double-sided adhesion exposure using a photomask, proximity method, A projection method and laser scanning exposure are mentioned. In the case of scanning exposure, a laser light source such as a He-Ne laser, He-Cd laser, argon laser, krypton ion laser, ruby laser, YAG laser, nitrogen laser, dye laser, or excimer laser is selected according to the emission wavelength of the SHG wavelength. Exposure can be carried out by converting and scanning exposure, or by scanning exposure using a liquid crystal shutter or micro-mirror array shutter.

As a method for developing a dry film resist according to the present invention, a developer suitable for the photocrosslinkable resin layer used is used and sprayed from the vertical direction of the substrate toward the substrate surface to remove unnecessary dry film resist (unexposed portion), , an etching resist 5 composed of a dry film resist pattern is formed. As a developing solution, generally 1-3 mass % sodium carbonate aqueous solution is used, More preferably, 1 mass % sodium carbonate aqueous solution is used.

As a method of peeling the dry film resist pattern used as the etching resist 5, a stripper suitable for the photocrosslinkable resin layer to be used is used, and the dry film resist pattern is removed by spraying it from the vertical direction of the substrate toward the substrate surface. do. As a stripping solution, 2-4 mass % of sodium hydroxide aqueous solution is generally used, More preferably, 3 mass % of sodium hydroxide aqueous solution is used.

In the present invention, the alkali-insoluble resin, the inorganic filler, and the organic filler can be simultaneously dispersed and removed because the time from the end of the etching process to the start of the next process, the water washing process, is within 30 seconds. The mechanism of this effect is only speculation, but it is thought that the alkali-insoluble resin remaining in the etching process immediately after the etching process, and the dispersed state of the inorganic filler and the organic filler are related. The alkali-insoluble resin, inorganic filler, and organic filler remaining in the etching process are in a mixed dispersed state immediately after the etching process. can However, when the time from the end of the etching process to the start of the water washing process exceeds 30 seconds, separation of the alkali-insoluble resin, the inorganic filler, and the organic filler proceeds, so that the component which is easily removed by water washing and the component which is not easily removed by water washing It is thought that the residue of the resin composition layer is generated after washing with water.

Example

Hereinafter, the present invention will be described in more detail by way of Examples, but the present invention is not limited to these Examples.

(Example 1-1 to 1-12, 1-14, 1-17 to 1-22)

25 mass% of PTFE as an organic filler, 40 mass% of spherical fused silica as an inorganic filler, 16 mass% of a biphenyl aralkyl type epoxy resin as an epoxy resin, 16 mass% of a phenol novolac type cyanate resin as a thermal curing agent, As a hardening accelerator, 2 mass % of triphenylphosphine, in addition, a coupling agent and a leveling agent are added, methyl ethyl ketone and cyclohexanone are mixed as a medium to what made the whole quantity 100 mass %, liquid resin composition got

Next, after apply|coating a liquid resin composition on a polyethylene terephthalate film (38 micrometers in thickness), it dried at 100 degreeC for 5 minutes, and the medium was removed. Thereby, the A-stage resin composition layer which has a film thickness of 20 micrometers and consists of a resin composition containing an alkali-insoluble resin, an inorganic filler, and an organic filler was formed.

Next, prepare a peelable metal foil in which a copper foil 6 having a thickness of 3 µm, a release layer, and a carrier foil are laminated in this order, and after thermocompressing both the copper foil and the resin composition layer in contact with each other, the release layer and the carrier foil was peeled, and the resin composition layer (4) to which the copper foil (6) adhered was obtained.

The copper foil 3' on one surface of the epoxy resin glass cloth base copper clad laminated board 1' (area 170 mm x 255 mm, copper foil thickness 12 micrometers, base material thickness 0.1 mm) was patterned, and the epoxy in which the conductor pattern was formed A resin glass cloth base material (circuit board (1)) was obtained. Next, the polyethylene terephthalate film is peeled off from the resin composition layer 4 to which the copper foil 6 is adhered, and on the epoxy resin glass cloth substrate on which the conductor pattern is formed, using a vacuum thermocompression laminator, a temperature of 100 ° C., After vacuum thermocompression bonding at a pressure of 1.0 Mpa, it heated at 130 degreeC for 45 minute(s), and the resin composition layer 4 of B-stage was formed.

Then, the copper foil 6 on the resin composition layer 4 was patterned, the opening part was formed in the predetermined|prescribed area|region of copper foil, and the resin composition layer 4 to which the etching resist (metal mask) adhered was prepared.

Next, through the etching resist 5, with the etching liquid of Table 1 and Table 2, the immersion process performed the etching process with respect to the resin composition layer 4 at 80 degreeC. After the etching step, the etchant remaining on the surface of the resin composition layer 4 is washed, and the resin residue 8 adhering to the surface of the connection pad 3 and the wall surface of the resin composition layer 4 is washed with ultrasonic waves. In order to remove it by irradiating it, the ultrasonic irradiation process of the immersion method with pure water was implemented as a water washing process. In addition, the ultrasonic irradiation process was performed by making the resin residue 8 adhering to the surface of the connection pad 3 and the wall surface of the resin composition layer 4 contact with the pure water which applied 45 kHz ultrasonic vibration for 60 second.

With respect to the etching solution treatment time, the opening length (a) of the etching resist 5, the film thickness (b) of the resin composition layer 4, and the bottom length (c) of the opening of the resin composition layer 4 described in FIG. 3 . ), the processing time at which a + 2b = c was defined as “standard processing time”. Specifically, since the opening length (a) of the etching resist 5 is 60 µm and the film thickness (b) of the resin composition layer 4 is 20 µm, the bottom length ( The treatment time for c) to be 100 µm ± 5 µm was referred to as “standard treatment time”, and is shown in Tables 1 and 2.

(resin residue)

The inside of the opening part of the etching resist 5 WHEREIN: It was evaluated whether removal of the resin composition layer 4 had become reliable. The results are shown in Tables 1 and 2. Evaluation criteria are shown below.

Evaluation standard

○ (Good): No resin residue remains inside the opening after ultrasonic water cleaning, or even if it remains, it is a level that can be removed in the additional water cleaning process by spraying.

△ (Satisfactory): A level that resin residues remain inside the opening after ultrasonic water cleaning and cannot be removed in an additional water cleaning process by spraying, but a level that can be easily removed by post-treatment such as plasma cleaning treatment.

x (Unsatisfactory): A level at which many resin residues remain inside the opening after ultrasonic water cleaning and cannot be removed even by post-treatment such as plasma cleaning treatment.

(Example 1-13)

Etching process by the method similar to Example 1-3, except that content of PTFE made content of 23 mass %, content of a spherical fused silica be 33 mass %, and made content of a biphenyl aralkyl type epoxy resin into 25 mass %. was carried out. A result is shown in Table 2.

(Example 1-15)

Etching process by the method similar to Example 1-3 except that content of PTFE was 15 mass %, content of spherical fused silica was 40 mass %, and content of a biphenyl aralkyl type epoxy resin was 26 mass %. was carried out. Although the etching time was extended to 30 minutes (1800 seconds), there was a large amount of resin residue on the conductor pattern surface and on the epoxy resin glass cloth base material, and the resin composition layer could not be etched. A result is shown in Table 2.

(Example 1-16)

Etching process by the method similar to Example 1-3 except that content of PTFE was 25 mass %, content of spherical fused silica was 25 mass %, and content of a biphenyl aralkyl type epoxy resin was 31 mass %. was carried out. Although the etching time was extended to 30 minutes, there was a large amount of resin residue on the conductor pattern surface and on the epoxy resin glass cloth base material, and the resin composition layer could not be etched. A result is shown in Table 2.

(Example 1-23)

The resin composition layer 4 with an etching resist obtained by the method similar to Example 1-1 was wet-blasted, and the etching resist 5 was removed after that. As a result of observing this with an optical microscope, there was a dispersion|variation in the etching amount of the resin composition layer 4, and there existed a point where the resin composition remained on the epoxy resin glass cloth base material. In addition, a number of flaws caused by wet blasting were confirmed in the conductor pattern to which a part or all of the surface was exposed.

(Example 2-1 to 2-14)

In the water cleaning step after the etching treatment, the resin when etching is performed by the etching method similar to Examples 1-1 to 1-14, except that the water cleaning step by spraying is not performed instead of the ultrasonic irradiation step. Tables 3 and 4 show the evaluation results of the residue.

As can be seen from the results of Tables 1 to 4, in the present invention, the resin composition containing the alkali-insoluble resin, the organic filler, and the inorganic filler can be efficiently removed (in particular, it can be stably removed without a resin residue). .

(Example 3-1 to 3-10, 3-12, 3-15 to 3-21)

The etching process was implemented by the method similar to Example 1-1 except having used the etching liquid shown in Table 5 or Table 6. A result is shown in Table 5 and Table 6.

(Example 3-11)

Etching process by the method similar to Example 3-3 except that content of PTFE was 23 mass %, content of spherical fused silica was 33 mass %, and content of a biphenyl aralkyl type epoxy resin was 25 mass %. was carried out. A result is shown in Table 6.

(Example 3-13)

Etching process by the method similar to Example 3-3 except that content of PTFE was 15 mass %, content of spherical fused silica was 40 mass %, and content of a biphenyl aralkyl type epoxy resin was 26 mass %. was carried out. Although the etching time was extended to 30 minutes (1800 seconds), there was a large amount of resin residue on the conductor pattern surface and on the epoxy resin glass cloth base material, and the resin composition layer could not be etched. A result is shown in Table 6.

(Example 3-14)

Etching process by the method similar to Example 3-3 except that content of PTFE was 25 mass %, content of spherical fused silica was 25 mass %, and content of a biphenyl aralkyl type epoxy resin was 31 mass %. was carried out. Although the etching time was extended to 30 minutes, there was a large amount of resin residue on the conductor pattern surface and on the epoxy resin glass cloth base material, and the resin composition layer could not be etched. A result is shown in Table 6.

(Example 4-1 to 4-12)

In the water cleaning step after the etching treatment, the resin when etching is performed by the etching method similar to Examples 3-1 to 3-12, except that the water cleaning step by spraying is not performed instead of the ultrasonic irradiation step. The evaluation results of the residues are shown in Tables 7 and 8.

As can be seen from the results in Tables 5 to 8, in the present invention, the resin composition containing the alkali-insoluble resin, the organic filler, and the inorganic filler can be efficiently removed (in particular, it can be stably removed without a resin residue). .

(Example 5-1 to 5-10, 5-12, 5-15 to 5-22)

The etching process was implemented by the method similar to Example 1-1 except having used the etching liquid shown in Table 9 or Table 10. The results are shown in Tables 9 and 10.

(Example 5-11)

Etching process by the method similar to Example 5-3 except that content of PTFE made content of 23 mass %, content of a spherical fused silica be 33 mass %, and having made content of a biphenyl aralkyl type epoxy resin 25 mass %. was carried out. A result is shown in Table 10.

(Example 5-13)

Etching process by the method similar to Example 5-3 except that content of PTFE was 15 mass %, content of spherical fused silica was 40 mass %, and content of a biphenyl aralkyl type epoxy resin was 26 mass %. was carried out. Although the etching time was extended to 30 minutes (1800 seconds), there was a large amount of resin residue on the conductor pattern surface and on the epoxy resin glass cloth base material, and the resin composition layer could not be etched. A result is shown in Table 10.

(Example 5-14)

Etching process by the method similar to Example 5-3 except that content of PTFE was 25 mass %, content of spherical fused silica was 25 mass %, and content of a biphenyl aralkyl type epoxy resin was 31 mass %. was carried out. Although the etching time was extended to 30 minutes, there was a large amount of resin residue on the conductor pattern surface and on the epoxy resin glass cloth base material, and the resin composition layer could not be etched. A result is shown in Table 10.

(Example 6-1 to 6-12)

In the water cleaning step after the etching treatment, the resin when etching is performed by the etching method similar to Examples 5-1 to 5-12, except that the water cleaning step by spraying is not performed instead of the ultrasonic irradiation step. Table 11 and Table 12 show the evaluation results of the residue.

As can be seen from the results in Tables 9 to 12, in the present invention, the resin composition including the alkali-insoluble resin, the organic filler and the inorganic filler can be efficiently removed (in particular, it can be stably removed without a resin residue) there is.

(Example 7)

25 mass% of PTFE as an organic filler, 40 mass% of spherical fused silica as an inorganic filler, 16 mass% of a biphenyl aralkyl type epoxy resin as an epoxy resin, 16 mass% of a phenol novolac type cyanate resin as a thermal curing agent, As a hardening accelerator, 2 mass % of triphenylphosphine, in addition, a coupling agent and a leveling agent are added, methyl ethyl ketone and cyclohexanone are mixed as a medium to what made the whole quantity 100 mass %, liquid resin composition got

Next, after apply|coating a liquid resin composition on a polyethylene terephthalate film (38 micrometers in thickness), it dried at 100 degreeC for 5 minutes, and the medium was removed. Thereby, the A-stage resin composition layer which has a film thickness of 20 micrometers and consists of a resin composition containing an alkali-insoluble resin, an organic filler, and an inorganic filler was formed.

Next, prepare a peelable metal foil in which a copper foil 6 having a thickness of 3 µm, a release layer, and a carrier foil are laminated in this order, and after thermocompressing both the copper foil and the resin composition layer in contact with each other, the release layer and the carrier foil was peeled, and the resin composition layer (4) to which the copper foil (6) adhered was obtained.

The copper foil 3' on one surface of the epoxy resin glass cloth base copper clad laminated board 1' (area 170 mm x 255 mm, copper foil thickness 12 micrometers, base material thickness 0.1 mm) was patterned, and the epoxy in which the conductor pattern was formed A resin glass cloth base material (circuit board (1)) was obtained. Next, the polyethylene terephthalate film is peeled off from the resin composition layer 4 to which the copper foil 6 is adhered, and on the epoxy resin glass cloth substrate on which the conductor pattern is formed, using a vacuum thermocompression laminator, a temperature of 100 ° C., After vacuum thermocompression bonding at a pressure of 1.0 Mpa, it heated at 130 degreeC for 45 minute(s), and the resin composition layer 4 of B-stage was formed.

Then, the copper foil 6 on the resin composition layer 4 is patterned, an opening is formed in a predetermined area|region of the copper foil 6, and the resin composition layer 4 to which the etching resist 5 (metal mask) was adhered. was prepared.

After each pretreatment liquid (30 ° C.) shown in Table 13 was brought into contact with the resin composition layer 4 and the metal mask 5 by immersion treatment for 5 minutes, a spray-type water washing treatment with pure water was performed for 1 minute, After improving the affinity of the etchant and the resin composition layer 4, the resin composition layer 4 is etched by immersion treatment at 80°C with each etchant shown in Table 14 through the metal mask 5. treatment was carried out. After the etching treatment, the etchant remaining on the surface of the resin composition layer 4 is washed, and the resin residue 8 adhering to the surface of the connection pad 3 and the wall surface of the resin composition layer 4 is subjected to ultrasonic waves. In order to remove it by irradiating it, ultrasonic water washing of an immersion method with pure water was performed. In addition, ultrasonic water washing was performed by making the resin residue 8 adhering to the surface of the connection pad 3 and the wall surface of the resin composition layer 4 contact for 60 second to the water which applied 45 kHz ultrasonic vibration.

With respect to the etching solution treatment time, the opening length (a) of the metal mask 5, the film thickness (b) of the resin composition layer 4, and the bottom length (c) of the opening of the resin composition layer 4, which are described in FIG. 3 . ), the processing time at which a + 2b = c was defined as “standard processing time”. Specifically, since the opening length (a) of the metal mask 5 is 50 µm and the film thickness (b) of the resin composition layer 4 is 20 µm, the bottom length of the opening of the resin composition layer 4 ( The treatment time at which c) becomes 90 µm ± 5 µm is referred to as “standard treatment time”, and is shown in Tables 13 and 14. In addition, the pH of each pretreatment liquid was adjusted using sulfuric acid or potassium hydroxide.

(small diameter opening)

When the opening length (a) of the metal mask 5 is 50 µm and the film thickness (b) of the resin composition layer 4 is 20 µm, by confirmation of 100 openings in the metal mask 5, the resin composition The following reference|standard evaluated whether the bottom length (c) of the opening part of the layer (4) was 90 micrometers +/-5 micrometers, and the small-diameter opening process was performed. The results are shown in Table 15.

Evaluation standard

○ (Good): Out of 100 small-diameter openings, the resin opening is 95 or more in the standard processing time.

Δ (Satisfactory): Out of 100 small-diameter openings in a standard processing time, the resin openings are 85 or more and less than 95.

× (Unsatisfactory): Out of 100 small-diameter openings in the standard processing time, less than 85 of the resin openings.

As can be seen from the results in Table 15, in the present invention, the opening diameter of the opening in the resin composition layer containing the alkali-insoluble resin, the organic filler, and the inorganic filler is not etched even in the small-diameter opening treatment to be Φ100 µm or less. can be suppressed and etched.

(Example 8-1 to 8-9)

25 mass% of PTFE as an organic filler, 40 mass% of spherical fused silica as an inorganic filler, 16 mass% of a biphenyl aralkyl type epoxy resin as an epoxy resin, 16 mass% of a phenol novolac type cyanate resin as a thermal curing agent, As a hardening accelerator, 2 mass % of triphenylphosphine, in addition, a coupling agent and a leveling agent are added, methyl ethyl ketone and cyclohexanone are mixed as a medium to what made the whole quantity 100 mass %, liquid resin composition got

Next, after apply|coating a liquid resin composition on a polyethylene terephthalate film (38 micrometers in thickness), it dried at 100 degreeC for 5 minutes, and the medium was removed. Thereby, the A-stage resin composition layer which has a film thickness of 20 micrometers and consists of a resin composition containing an alkali-insoluble resin, an organic filler, and an inorganic filler was formed.

Next, prepare a peelable metal foil in which a copper foil 6 having a thickness of 3 µm, a release layer, and a carrier foil are laminated in this order, and after thermocompressing both the copper foil and the resin composition layer in contact with each other, the release layer and the carrier foil was peeled, and the resin composition layer (4) to which the copper foil (6) adhered was obtained.

The copper foil 3' on one surface of the epoxy resin glass cloth base copper clad laminated board 1' (area 400 mm x 500 mm, copper foil thickness 12 micrometers, base material thickness 0.1 mm) was patterned, and the conductor pattern A was The epoxy resin glass cloth base material (circuit board (1)) which was arrange|positioned equally in the plane in the horizontal direction by 10 pieces and 12 pieces in the vertical direction was obtained. Next, the polyethylene terephthalate film is peeled from the resin composition layer 4 to which the copper foil 6 is adhered, and on the epoxy resin glass cloth substrate on which the conductor pattern A is formed, using a vacuum thermocompression bonding laminator, the temperature is 100°C. , After vacuum thermocompression bonding at a pressure of 1.0 Mpa, it heated at 130 degreeC for 45 minute(s), and the resin composition layer 4 of the B stage was formed.

Then, the copper foil 6 on the resin composition layer 4 is patterned, an opening is formed in a predetermined area|region of the copper foil 6, and the resin composition layer 4 to which the etching resist (metal mask) 5 was adhered. was prepared.

Next, through the etching resist 5, with the etching liquid of Table 16, the etch process was implemented with respect to the resin composition layer 4 by immersion treatment at 80 degreeC. Next, after "the time from the end of the etching process to the start of the water washing process" described in Table 16, the alkali-insoluble resin, organic filler, and inorganic filler remaining in the etching treatment part are removed by washing with water by ultrasonic irradiation of an immersion method with pure water. A water washing process was performed. Then, it wash|cleaned further by the spray treatment with pure water.

The opening of the etching resist 5 WHEREIN: The "resin residual" evaluated whether the removal of the resin composition layer 4 was reliable. Moreover, as evaluation of the deformation|transformation in the opening shape of the resin composition layer 4, "undercut" was evaluated. In addition, as evaluation of "in-plane uniformity", openings at 120 points with the same target aperture diameter (target aperture diameter) were observed, and the aperture diameter of the aperture with the largest aperture diameter was set to the "maximum value" and the aperture diameter to be the minimum aperture diameter. The aperture diameter of phosphorus aperture was made into "minimum value", the variation value (%) was calculated|required by "(maximum value - minimum value) / target aperture diameter x 100", and "in-plane uniformity" was evaluated. A result is shown in Table 16. The criteria for each evaluation are shown below.

(Evaluation Criteria for Resin Residue)

○ (Very Good): No resin composition remains on the surface.

○△ (Good): A level at which a trace amount of the resin composition remains on the surface, but does not pose a problem.

△ (Satisfactory): A level at which a trace amount of the resin composition remains on the surface, but can be easily removed by plasma cleaning treatment.

x (Unsatisfactory): The level which many resin composition remains on the surface after etching and is not removed by a plasma cleaning process.

(Evaluation criteria for undercut)

○ (Very Good): Undercut is not seen in the resin composition layer

○ △ (Good): A very small undercut is not seen on the bottom surface of the resin composition layer.

△ (Satisfactory): A level at which a small undercut is seen on the bottom surface of the resin composition layer, but does not pose a problem.

x (Unsatisfactory): The large undercut which becomes a problem practically is seen in the bottom surface of a resin composition layer.

(Evaluation criteria for in-plane uniformity)

○ (Very Good): Very high uniformity. The variation value is less than 3%.

○△ (Good): High uniformity. The fluctuation value is 3% or more and less than 5%.

△ (Satisfactory): uniform. The fluctuation value is 5% or more and less than 6%.

× (Unsatisfactory): It cannot be said to be uniform. The variation value is 6% or more.

As can be seen from the results in Table 16, in the etching method for etching a resin composition containing an alkali-insoluble resin, 20 to 40 mass% of an organic filler, and 30 to 50 mass% of an inorganic filler, the etching solution of the present invention It turns out that in-plane uniformity is high by including the etching process by and a water washing process in this order. Moreover, it turns out that there is also little generation|occurrence|production of an undercut. And it turns out that there are few residues of a resin composition and it can remove stably because time from the end of an etching process to the start of a water washing process is less than 30 seconds.

(Example 9-1 to 9-8)

25 mass% of PTFE as an organic filler, 40 mass% of spherical fused silica as an inorganic filler, 16 mass% of a biphenyl aralkyl type epoxy resin as an epoxy resin, 16 mass% of a phenol novolac type cyanate resin as a thermosetting agent, As a hardening accelerator, 2 mass % of triphenylphosphine, in addition, a coupling agent and a leveling agent are added, methyl ethyl ketone and cyclohexanone are mixed as a medium to what made the whole quantity 100 mass %, liquid resin composition got

Next, after apply|coating a liquid resin composition on a polyethylene terephthalate film (38 micrometers in thickness), it dried at 100 degreeC for 5 minutes, and the medium was removed. Thereby, the A-stage resin composition layer which has a film thickness of 20 micrometers and consists of a resin composition containing an alkali-insoluble resin, an inorganic filler, and an organic filler was formed.

Next, prepare a peelable metal foil in which a copper foil 6 having a thickness of 3 µm, a release layer, and a carrier foil are laminated in this order, and after thermocompressing both the copper foil and the resin composition layer in contact with each other, the release layer and the carrier foil was peeled, and the resin composition layer (4) to which the copper foil (6) adhered was obtained.

The copper foil 3' on one surface of the epoxy resin glass cloth base copper clad laminated board 1' (area 170 mm x 255 mm, copper foil thickness 12 micrometers, base material thickness 0.1 mm) was patterned, and the epoxy in which the conductor pattern was formed A resin glass cloth base material (circuit board (1)) was obtained. Next, the polyethylene terephthalate film is peeled off from the resin composition layer 4 to which the copper foil 6 is adhered, and on the epoxy resin glass cloth substrate on which the conductor pattern is formed, using a vacuum thermocompression laminator, a temperature of 100 ° C., After vacuum thermocompression bonding at a pressure of 1.0 Mpa, it heated at 130 degreeC for 45 minute(s), and the resin composition layer 4 of B-stage was formed.

Then, the copper foil 6 on the resin composition layer 4 was patterned, the opening part was formed in the predetermined|prescribed area|region of copper foil, and the resin composition layer 4 to which the etching resist (metal mask) adhered was prepared.

Through the etching resist 5, the resin composition layer 4 was etched by an immersion process at 80 degreeC with the etching liquid of Table 17. The washing|cleaning process which removes the etching liquid remaining and adhering to the surface of the resin composition layer 4 was performed after an etching process. In the washing process, a spray method with pure water was used.

With respect to the etching solution treatment time, the opening length (a) of the etching resist 5, the film thickness (b) of the resin composition layer 4, and the bottom length (c) of the opening of the resin composition layer 4 described in FIG. 3 . ), the processing time at which a + 2b = c was defined as “standard processing time”. Specifically, since the opening length (a) of the etching resist 5 is 50 µm and the film thickness (b) of the resin composition layer 4 is 20 µm, the bottom length ( Table 17 shows the treatment time in which c) becomes 90 µm ± 5 µm as “standard treatment time”.

The above-mentioned "resin residue" evaluated whether the removal of the resin composition layer 4 was reliable in the inside of the opening part of the metal mask 5. As shown in FIG. A result is shown in Table 17.

As can be seen from the results in Table 17, in the present invention, the resin composition including the alkali-insoluble resin, the organic filler, and the inorganic filler can be efficiently removed (in particular, it can be stably removed without a resin residue). In particular, by using an aromatic alcohol, the resin composition was able to be efficiently removed even without ultrasonic water washing.

Industrial Applicability

In the etching solution and etching method of the present invention, an insulating resin composition layer excellent in heat resistance, dielectric properties, mechanical strength, chemical resistance, etc. filled with a high content of organic fillers and inorganic fillers can be etched, for example, multilayer It can be applied to microfabrication of insulating resins in build-up wiring boards, component-embedded module boards, flip-chip package boards, and package board mounting motherboards.

1: circuit board
1': copper clad laminate
2: insulating layer
3: Solder connection pad, connection pad
3' : copper foil
4: resin composition layer
5: Etching resist (metal mask, dry film resist pattern)
6: Copper foil, dry film resist
8: resin residue
a: opening length of etching resist 5
b: the film thickness of the resin composition layer (4)
c: bottom length of the resin composition layer 4

Claims (14)

In the etchant of a resin composition comprising an alkali-insoluble resin, 20 to 40% by mass of an organic filler, and 30 to 50% by mass of an inorganic filler, the etchant comprises 15 to 45% by mass of an alkali metal hydroxide as a first component and an agent A polyol compound containing 1-40 mass % of an ethanolamine compound as a 2 component, and 3-60 mass % of 3 or more hydroxyl groups as a 3rd component, a 2-20 mass % polyhydric carboxylic acid compound; Or 2-20 mass % of a hydroxy acid compound is contained, The etching liquid characterized by the above-mentioned. The method of claim 1,
The etchant having a molecular weight of 80 or more and 200 or less of the polyol compound having three or more hydroxyl groups. The method of claim 1,
Etching liquid in which the said polyol compound which has 3 or more hydroxyl groups contains glycerol. The method of claim 1,
The etching liquid in which the said etching liquid contains 0.1-3 mass % of aromatic alcohol compounds. A resin composition comprising a step of etching a resin composition comprising an alkali-insoluble resin, 20 to 40 mass% of an organic filler, and 30 to 50 mass% of an inorganic filler using the etching solution according to claim 1; Etching method. An etching process of etching a resin composition comprising an alkali-insoluble resin, 20 to 40 mass% of an organic filler, and 30 to 50 mass% of an inorganic filler using the etching solution according to claim 1, and ultrasonic wave irradiation after the etching process An etching method of a resin composition characterized by comprising an ultrasonic irradiation step. 7. The method according to claim 5 or 6,
The etching method of the resin composition which further has the process of pre-processing with the pretreatment liquid which consists of an acidic aqueous solution containing 2.5-7.5 mass % of anionic surfactant before an etching process. 7. The method according to claim 5 or 6,
It has a water washing process after an etching process, The etching method of the resin composition whose time from the completion of an etching process to the start of a water washing process is less than 30 seconds. 7. The method according to claim 5 or 6,
An etching process WHEREIN: The etching method of a resin composition using an etching resist, and the etching resist is a metal mask or a dry film resist. delete delete delete delete delete

Images