JP2002229219A - Developer used for formation of via hole and method for manufacturing multilayered print wiring board by using the developer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer which is capable of improving the resolution of via holes in a photosensitive insulating resin layer without changing the conventional equipment and conventional methods in the manufacture of a multilayered printed wiring board by using a photosensitive insulating resin and to provide a method for manufacturing a multilayered printed wiring board by using the developer. SOLUTION: When a photosensitive insulating resin layer is formed on a printed wiring board and via holes are formed by exposure and development in the process of manufacturing the multilayered printed wiring board by using a photosensitive insulating resin, a developer to which a surfactant is added, used to increase the affinity between the developer and the photosensitive insulating resin so that the resolution of via holes can be improved without changing the conventional equipment and conventional methods.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer used for forming via holes in a multilayer printed wiring board and a method for manufacturing a multilayer printed wiring board using the developer.

[0002]

2. Description of the Related Art The integration density of electronic components such as semiconductor chips tends to be very high, and the density of printed wiring boards on which such components are mounted has been reduced by reducing the spacing between wiring and connecting holes. . Further, in the multilayer printed wiring board, a conductor circuit is formed in advance on a plurality of substrates, and these are joined to each other to achieve higher density.

This multilayer printed wiring board is formed by multilayering a printed wiring board on which a conductor circuit has been formed in advance by a glass cloth prepreg. However, with the thinner and finer pitch required year by year, the cost and cost of a multilayer board using prepreg
There is a problem with the overall thickness and the like.

[0004] Therefore, in recent years, a technique for forming a multilayer using a resin instead of a prepreg has been developed. This is a method in which an insulating resin is formed on a printed wiring board which has been subjected to an inner layer treatment to form a multilayer, and a wiring pattern is formed thereon. In one of the methods, a photosensitive insulating resin layer is formed on a printed wiring board on which a first circuit is formed, a via hole is formed by exposure and development, and plating is performed on the photosensitive insulating resin layer. Method of forming conductor wiring pattern (photo method)
There is.

[0005]

The formation of via holes in the above-mentioned photo method usually involves spraying a developing solution onto a photosensitive insulating resin exposed through a photomask.
This is performed by selectively removing the photosensitive insulating resin. In the photo method, formation of a small-diameter via hole, that is, improvement in the resolution of the via hole is a key to increasing the density of the printed wiring board. However, when the diameter of the via hole to be formed is small, that is, when the aspect ratio is high, the developer hardly flows into the via hole, and the development becomes difficult.

The present invention solves the above-mentioned phenomena, improves the via hole resolution of the photosensitive insulating resin layer without changing the conventional equipment and the conventional method, and makes it possible to provide a high-density multilayer printed wiring board. A developer and a method for manufacturing a multilayer printed wiring board using the developer are proposed.

[0007]

According to the present invention, in a manufacturing process of a multilayer printed wiring board using a photosensitive insulating resin, a photosensitive insulating resin layer is formed on the printed wiring board, and a via hole is formed by exposure and development. When forming, using a developer with a surfactant added, and increasing the affinity between the developer and the photosensitive insulating resin, it is possible to improve the via hole resolution without changing the conventional equipment and method. did.

[0008]

Next, a developer according to the present invention and a method for manufacturing a multilayer printed wiring board using the developer will be described in detail.

In the present invention, the surfactant contained in the developer is not particularly limited, but a surfactant having a large effect of increasing the wettability of the photosensitive insulating resin with respect to the developer is preferable. N-acyl amino acid salts, alkyl ether carboxylates, carboxylates such as acylated peptides, alkyl sulfonates, alkyl benzene sulfonates, alkyl naphthalene sulfonates, sulfosuccinates, N-acyl sulfonates, α- Sulfonates such as olefin sulfonates, alkyl sulfates, alkyl ether sulfates, alkyl allyl ether sulfates, sulfate salts such as alkyl amide sulfates, alkyl phosphates, alkyl ether phosphates, alkyl allyl ether phosphates, etc. Phosphoric acid ester salts and Sufon acid salts and the like, aliphatic amine salt as a cationic, quaternary ammonium salts, phosphonium salts, sulfonium salts and the like. Examples of the amphoteric,
Betaine such as carboxybetaine and sulfobetaine, aminocarboxylates and imidazoline derivatives, etc., and nonionic esters such as fatty acid monoglycerin ester, fatty acid polyglycol ester, fatty acid sorbitan ester, fatty acid propylene glycol ester, fatty acid sucrose ester Type, fatty acid alkanolamide, higher alkylamine polyethylene oxide,
Examples include nitrogen-containing types such as higher fatty acid amide polyethylene oxide, ether types such as higher alcohol polyethylene oxide and alkylphenol polyethylene oxide, and ether ester types such as higher fatty acid polyethylene oxide.

Further, the wettability of the photosensitive insulating resin with respect to the developing solution is particularly preferably such that the contact angle of the developing solution added with the surfactant to the photosensitive insulating resin is 30 ° or less,
When the contact angle is larger than 30 °, the wettability is insufficient and the improvement in resolution cannot be expected.

The selected surfactant is added to the photosensitive insulating resin in an amount of 0.001% by weight to 20% by weight, especially 0.001% by weight, so that the contact angle of the developer added with the surfactant to the photosensitive insulating resin is 30 ° or less. Preferably, 0.01 to 5% by weight is added. If the amount is less than 0.001% by weight, the effect of improving the wettability by the addition of a surfactant may not be obtained. If the amount is more than 20% by weight, problems may occur such as impairing the developing ability of the developer.

In the present invention, the type of the developer to which the surfactant selected from the above is added is not particularly limited as long as it selectively elutes the photosensitive insulating resin. Determined by the development type of positive or negative type, common ones such as alkaline developer, semi-aqueous developer, solvent developer and emulsion developer can be used. Is applied to the photosensitive insulating resin layer.

In order to suppress foaming of the developer according to the present invention, an antifoaming agent may be appropriately added, and those commonly used such as alcohols, nonionic surfactants and silicone oils may be used. Can be added.

In the present invention, the exposure treatment, which is a stage prior to the development treatment, can be performed by a conventional method. For example, an ultrahigh-pressure mercury lamp, a high-pressure mercury lamp, or the like is used as a light source, and imagewise exposure can be performed directly on a layer of the photosensitive insulating resin composition through a photomask or via a transparent film such as a polyethylene terephthalate film.

The photosensitive insulating resin in which the via hole is formed by using the developer of the present invention may be of either a radical polymerization type or a kaolin polymerization type, and is not limited as long as it can be generally used. Also, the form of the photosensitive insulating resin before forming the resin layer on the printed wiring board,
Liquid or film-like materials are used, for example, when the photosensitive insulating resin is liquid, a comma coater, a blade coater, a lip coater, a rod coater, a squeeze coater, a reverse roll coater, a transfer roll coater, etc. The photosensitive insulating resin layer is formed by applying a uniform thickness, heating and drying to evaporate the solvent. In the case of a film, the photosensitive insulating resin layer can be easily formed on the printed wiring board by bonding using a hot roll laminator or the like. The thickness of the photosensitive insulating resin layer is not particularly limited as long as it is uniform, and is usually appropriately selected in the range of 10 to 150 μm.

Further, in the method of manufacturing a multilayer printed wiring board using the developing solution according to the present invention, a normal multilayer printed wiring board such as cleaning, etching, resist peeling, formation of a protective film, etc., other than the above-mentioned processing steps is manufactured. Regarding the steps required above, it is possible to manufacture a multilayer printed wiring board without changing the conventional equipment and the conventional method.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

EXAMPLES (Example 1) (1) Photo-via film BF-8500 as photosensitive insulating resin
(Resin thickness: 75 μm) (trade name, manufactured by Hitachi Chemical Co., Ltd.), which was used as a glass-epoxy resin copper-clad laminate (laminate thickness: 0.6 mm, copper foil thickness: 18 μm) MCL-E-67 ( Hitachi Chemical Co., Ltd.
(Trade name, product name) was subjected to a copper blackening treatment, and a photo via film BF-8500 was laminated with a roll laminator to form a photosensitive insulating resin layer. (2) Exposure amount to the surface on which the photosensitive insulating resin layer of (1) was formed, through a photomask in which a portion to be a via hole is shielded
By irradiating with ultraviolet light of 500 mJ / cm ² and developing with the following developing solution and developing conditions, a light-shielding portion was selectively removed to form a via hole. Developer composition used in Example 1 Water 900 ml / l diethylene glycol monobutyl ether 100 ml / l borax 15 g / l surfactant (Tohoru N-207M: trade name, manufactured by Toho Chemical Co., Ltd.) 30 g / l defoamer ( Antix # 100: Maruzen Pharmaceutical Co., Ltd. 1g / l Development conditions Development method Spray development (spray pressure: 80kPa) Development temperature 30 ° C Development time 6 minutes (3) (2), 30 at 80 ° C After drying, the via holes were observed with an electron microscope to evaluate the via hole resolution. Table 1 shows the results. (4) The developer of (2) was dropped on the photosensitive insulating resin surface of the unexposed photovia film BF-8500, and the contact angle was measured. In addition, the measured value was shown by the average value of n = 3. Table 1 shows the results. (5) The minimum development time, which is a measure of the developability of the photosensitive insulating resin, was measured by the following method. Photo Via Film BF
After cutting -8500 into 30 mm x 30 mm, the developer of (2) was sprayed onto the photosensitive insulating resin surface of this sample in the unexposed state under the developing conditions of (2), and the film was completely removed from PET. The time until removal (minimum development time) was measured. In addition, the measured value was shown by the average value of n = 3. Table 1 shows the results.

Example 2 In Example 2, the conditions were the same as in Example 1 except that the following developer was used.
Evaluation of via hole resolution, contact angle and minimum development time was performed. Table 1 shows the results. Developer composition used in Example 2 Water 900 ml / l Diethylene glycol monobutyl ether 100 ml / l Borax 15 g / l Surfactant (Nonal 912: trade name, manufactured by Toho Chemical Co., Ltd.) 30 g / l Antifoaming agent (antix # 100: Maruzen Pharmaceutical Co., Ltd.) 1g / l

(Comparative Example) In Comparative Example, the same conditions as in Example 1 were used except that the following developer was used, and the evaluation of the via hole resolution, the contact angle and the minimum developing time were performed. Table 1 shows the results. Developer composition used in Comparative Examples Water 900 ml / l ethylene glycol monobutyl ether 100 ml / l borax 15 g / l defoamer (Antiox # 100: manufactured by Maruzen Pharmaceutical Co., Ltd.) 1 g / l

[0020]

[Table 1]

From Table 1, it can be easily understood that the use of the developing solutions in Examples 1 and 2 has a better via hole resolution than using the developing solution of Comparative Example.

Although the present invention has been described with reference to a plurality of embodiments, it should be understood that the description is not intended to limit the present invention. From this disclosure, various alternative embodiments, examples, and operation techniques not described herein will be apparent to those skilled in the art. Therefore, the technical scope of the present invention is determined only by the matters specifying the invention according to the claims that are appropriate from the above description.

[0023]

As described above, by using the developer according to the present invention, the resolution of the via hole of the photosensitive insulating resin layer can be improved without changing the conventional equipment and the conventional method. It has become possible to provide high density multilayer printed wiring boards.

Claims (3)

[Claims] 1. A developing solution used for forming a via hole in a photosensitive insulating resin layer in the production of a multilayer printed wiring board, the developing solution comprising a surfactant. 2. The developer according to claim 1, further comprising a surfactant so that a contact angle of the developer with the photosensitive insulating resin layer is 30 ° or less. 3. A method of manufacturing a multilayer printed wiring board using a photosensitive insulating resin as an insulating layer, wherein the developer according to claim 1 or 2 is used when forming a via hole. Manufacturing method of printed wiring board.