JPH01109792A - Printed wiring board - Google Patents
Printed wiring boardInfo
- Publication number
- JPH01109792A JPH01109792A JP26622487A JP26622487A JPH01109792A JP H01109792 A JPH01109792 A JP H01109792A JP 26622487 A JP26622487 A JP 26622487A JP 26622487 A JP26622487 A JP 26622487A JP H01109792 A JPH01109792 A JP H01109792A
- Authority
- JP
- Japan
- Prior art keywords
- dry film
- thickness
- printed wiring
- layer
- photosensitive dry
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000007772 electroless plating Methods 0.000 claims abstract description 8
- 238000007747 plating Methods 0.000 abstract description 23
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 abstract description 19
- 229910052802 copper Inorganic materials 0.000 abstract description 19
- 239000010949 copper Substances 0.000 abstract description 19
- 230000007547 defect Effects 0.000 abstract description 13
- 238000000034 method Methods 0.000 abstract description 10
- 239000000758 substrate Substances 0.000 abstract description 6
- 230000008021 deposition Effects 0.000 abstract description 4
- 239000007767 bonding agent Substances 0.000 abstract 2
- 239000010410 layer Substances 0.000 description 28
- 238000004519 manufacturing process Methods 0.000 description 9
- 230000000052 comparative effect Effects 0.000 description 6
- 239000004698 Polyethylene Substances 0.000 description 4
- 238000005530 etching Methods 0.000 description 4
- -1 polyethylene Polymers 0.000 description 4
- 229920000573 polyethylene Polymers 0.000 description 4
- UOCLXMDMGBRAIB-UHFFFAOYSA-N 1,1,1-trichloroethane Chemical compound CC(Cl)(Cl)Cl UOCLXMDMGBRAIB-UHFFFAOYSA-N 0.000 description 2
- 239000012790 adhesive layer Substances 0.000 description 2
- 239000005001 laminate film Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000004593 Epoxy Substances 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000010526 radical polymerization reaction Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 230000002747 voluntary effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/10—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern
- H05K3/18—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using precipitation techniques to apply the conductive material
- H05K3/181—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using precipitation techniques to apply the conductive material by electroless plating
- H05K3/182—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using precipitation techniques to apply the conductive material by electroless plating characterised by the patterning method
- H05K3/184—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using precipitation techniques to apply the conductive material by electroless plating characterised by the patterning method using masks
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Manufacturing Of Printed Wiring (AREA)
- Non-Metallic Protective Coatings For Printed Circuits (AREA)
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明はプリント配線板に関し、特に、感光性ドライフ
ィルムを使用してパターンを形成するプリント配線板に
関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a printed wiring board, and particularly to a printed wiring board in which a pattern is formed using a photosensitive dry film.
〈従来の技術)
電子n器の小形化、高性能化、及び高1能化等に伴い、
内部に組み込まれたプリント配線板も小形化、高密度化
へと改良が進んでいる。<Conventional technology> With the miniaturization, higher performance, and higher performance of electronic devices,
The printed wiring boards built inside are also becoming smaller and more densely packed.
従来、高密度のプリント配線板を製造するのに、感光性
ドライフィルムをレジストとして使用したエツチング払
が用いられている。しかし、エツチング仏によると、箔
の両側までエツチングされイのエツチング吊の制御が困
難であり、通常、Jワさの1/2まで片側がエツチング
されることを考慮し、ラインとスペースの台幅は120
μ汎が限度であった。Conventionally, etching using a photosensitive dry film as a resist has been used to manufacture high-density printed wiring boards. However, according to the Etching Buddha, it is difficult to control the etching suspension because both sides of the foil are etched, and one side is usually etched up to 1/2 of the J width. is 120
The limit was the μ-pan.
従って、ライン・スペース幅が120μm未満のさらに
高密度のプリント配線板を製造するために、最近フォト
法を用いた無電解めっき法が利用されるようになってき
た。このフォト法は、感光性レジストフィルム又は液状
レジストを用いて回路と逆パターンを形成し、そのレジ
ストの側壁に沿ってめっきを設けるものである。Therefore, in order to manufacture even higher-density printed wiring boards with a line space width of less than 120 μm, electroless plating using a photo method has recently come to be used. In this photo method, a pattern opposite to the circuit is formed using a photosensitive resist film or a liquid resist, and plating is provided along the sidewalls of the resist.
(発明が解決しようとする問題点)
しかし、フォト法を用いた無電解めっき法には次の欠点
があった。(Problems to be Solved by the Invention) However, the electroless plating method using the photo method has the following drawbacks.
先ず第1に、液状レジストは、スルーホール基板に用い
ると、スルーホール内に入り込み、除去が困難であると
いう欠点がある。First, when liquid resist is used in a through-hole substrate, it has the disadvantage that it gets into the through-holes and is difficult to remove.
第2に、従来の感光性ドライフィルムは厚さが22μm
以上あり、このフィルムに波長350〜400amの紫
外線を照射して露光してラジカル重合させ永久レジスト
層にする。しかし、フィルムの表面に汚れがあると、上
層部の方は下層部よりも多く紫外線を吸収するために光
吸収エネルギーが大きく、重合度が進行するが、下層部
は重合不足となる。従って、現像後、基板との界1面に
現BI液が浸透し、空隙ができ易く、その後の無電解め
っき処理によりこの空隙にめっきが形成されて、ショー
ト不良を発生する。この対策としては露光室を増加すれ
ばよいが、エツチング法と同様に紫外線の反射によりレ
ジストのサイドが幅広となりめっき層の側面が細くなる
欠点がある。また、ライン・スペース幅が100μm以
下になると、汚れを目視で検出することが困難になり除
去し難く、ショート不良がより増加する欠点がある。Second, the conventional photosensitive dry film has a thickness of 22 μm.
This film is irradiated with ultraviolet light having a wavelength of 350 to 400 am and exposed to radical polymerization to form a permanent resist layer. However, if there is dirt on the surface of the film, the upper layer absorbs more ultraviolet rays than the lower layer, so the light absorption energy is greater and the degree of polymerization progresses, but the lower layer becomes insufficiently polymerized. Therefore, after development, the current BI solution permeates the interface with the substrate, easily creating voids, and the subsequent electroless plating process forms plating in these voids, resulting in short-circuit defects. A countermeasure against this problem is to increase the number of exposure chambers, but, like the etching method, it has the disadvantage that the sides of the resist become wider due to the reflection of ultraviolet rays and the sides of the plating layer become thinner. Further, when the line space width is less than 100 μm, it becomes difficult to visually detect and remove dirt, and there is a drawback that short-circuit defects are more likely to occur.
第3に、無電解めっき法ではコム状端子を有する電子部
品を考慮して、めっき層を永久レジスト層の厚さとほぼ
同じ厚さに形成する必要がある。Thirdly, in the electroless plating method, it is necessary to form the plating layer to approximately the same thickness as the permanent resist layer in consideration of electronic components having comb-shaped terminals.
そのためにめっき時間が長くなり、高価になる欠点があ
り、また、永久レジスト層の表面にめっきが付着(以下
調時りという)することが多くなりショート不良が増加
するという欠点がある。Therefore, there is a drawback that the plating time becomes long and the cost becomes high, and there is also a drawback that the plating often adheres to the surface of the permanent resist layer (hereinafter referred to as "timing"), resulting in an increase in short-circuit defects.
本発明の目的は、以上の欠点を改良し、製造が容易でシ
ョート不良等を低減しつるプリント配線板を提供するも
のである。An object of the present invention is to improve the above-mentioned drawbacks, to provide a hanging printed wiring board that is easy to manufacture and reduces short-circuit defects.
(問題点を解決するための手段)
本発明は、上記の目的を達成するために、感光性ドライ
フィルムを紫外線露光により永久レジスト層とし、無電
解めっき法により回路を形成するプリント配線板におい
て、感光性ドライフィルムの厚さが5〜20μmである
ことを特徴とするプリント配線板を提供するものである
。(Means for Solving the Problems) In order to achieve the above object, the present invention provides a printed wiring board in which a photosensitive dry film is made into a permanent resist layer by exposure to ultraviolet rays and a circuit is formed by electroless plating. The present invention provides a printed wiring board characterized in that the thickness of the photosensitive dry film is 5 to 20 μm.
(作用)
本発明によれば、感光性ドライフィルムの厚さを従来よ
りも薄クシているために、めっき層も薄くてよく製造が
容易になり、銅降りによるショート不良等を低減できる
。(Function) According to the present invention, since the thickness of the photosensitive dry film is thinner than that of the conventional film, the plating layer is also thin and manufacturing is easy, and short circuit defects due to copper deposition can be reduced.
なお、感光性ドライフィルムの厚さは5〜20そのため
にめっき時間が長くなり、高価になる欠点があり、また
、永久レジスト層の表面にめっきが付着(以下調時りと
いう)することが多くなりショート不良が増加するとり
う欠点がある。In addition, the thickness of the photosensitive dry film is 5 to 20 mm, which has the disadvantage that the plating time is long and expensive, and the plating often adheres to the surface of the permanent resist layer (hereinafter referred to as "timing"). This has the disadvantage that the number of short-circuit defects increases.
本発明の目的は、以上の欠点を改良し、製造が容易でシ
ョート不良等を低減しつるプリント配線板を提供するも
のである。An object of the present invention is to improve the above-mentioned drawbacks, to provide a hanging printed wiring board that is easy to manufacture and reduces short-circuit defects.
(問題点を解決するための手段)
本光明は、上記の目的を達成するために、感光性ドライ
フィルムを紫外線露光により永久レジスト層とし、無電
解めっき法により回路を形成するプリント配線板におい
て、感光性ドライフィルムの厚さが5〜20μ卯である
ことを特徴とするプリント配線板を提供するものである
。(Means for Solving the Problems) In order to achieve the above object, the present Komei provides a printed wiring board in which a photosensitive dry film is made into a permanent resist layer by exposure to ultraviolet rays and a circuit is formed by electroless plating. The present invention provides a printed wiring board characterized in that the thickness of the photosensitive dry film is 5 to 20 μm.
(作用)
本発明によれば、感光性ドライフィルムの厚さを従来よ
りも薄クシているために、めっき層も薄くてよく製造が
容易になり、銅降りによるショート不良等を低減できる
。(Function) According to the present invention, since the thickness of the photosensitive dry film is thinner than that of the conventional film, the plating layer is also thin and manufacturing is easy, and short circuit defects due to copper deposition can be reduced.
なお、感光性ドライフィルムの厚さは5〜20上記実施
例を製造するには、先ず、絶縁基板1の表面にI着剤層
2を設け、スルーホール3を真2に張り付け、波長35
0〜4505mの紫外線を照射して露光し永久レジスト
層4として残す。The thickness of the photosensitive dry film is 5 to 20. To manufacture the above example, first, the I adhesive layer 2 is provided on the surface of the insulating substrate 1, the through holes 3 are pasted in the vertical direction, and the wavelength is 35.
It is exposed to ultraviolet rays of 0 to 4505 m and left as a permanent resist layer 4.
永久レジスト層を形成後、無電解銅めっき法により銅め
っき層5を形成する。After forming the permanent resist layer, a copper plating layer 5 is formed by electroless copper plating.
次に、上記実施例と比較例につき銅降りとショート不良
を調べたところ表の通りの結果が得られた。実施例と比
較例の製造条件は次の通りである。Next, copper fall-off and short-circuit defects were investigated for the above examples and comparative examples, and the results shown in the table were obtained. The manufacturing conditions for Examples and Comparative Examples are as follows.
実施例1):
a)絶縁基板
厚さ1.6sm、幅20C)n+、長さ500Mの、触
媒入り接着剤を両面に
塗布したガラスエポキシ基材(日立化
成工業株式会社製ACL−E−168>b)永久レジス
ト層
内に感光性ドライフィルム(厚さ22
μm)を挟持した、ラミネートフィル
ム(日立化成工業株式会社MSR−
3000−22>の感光性ドライフィ
ルムの層のみを取り出し、1.1.1
トリクロルエタンで溶解してlQwt%の溶液を作製す
る。イしてこの液を厚
さ25μmのポリエチレンプレフタレ
ートフィルムに塗布、乾燥して厚さ
17μmの感光性ドライフィルムの層
を形成する。さらにこの感光性ドライ
フィルムの層の表面に厚さ35μmの
ポリエチレンフィルムをラミネートす
る。次にこのラミネートフィルムを用
い、先ず、ポリエチレンフィルムを剥
離しながら感光性ドライフィルムを接
着剤層2に張り付ける。この状態で、
ライン・スペース幅75μmの回路の
ネガフィルムを用い、紫外線を照射し
露光量18011J/ cmで露光する。露光後、ポリ
エチレンプレフタレートフィ
ルムを剥離し、温度80℃で5分間加
熱する。加熱後、1.1.1トリクロ
ルエタンの現像液により現像し、永久
レジスト層4を形成する。Example 1): a) Insulating substrate thickness 1.6 sm, width 20 C) n+, length 500 M, glass epoxy base material coated with catalyst-containing adhesive on both sides (ACL-E-168 manufactured by Hitachi Chemical Co., Ltd.) >b) Take out only the photosensitive dry film layer of the laminate film (Hitachi Chemical Co., Ltd. MSR-3000-22) in which a photosensitive dry film (thickness 22 μm) is sandwiched between the permanent resist layers, and perform 1.1 .1 Dissolve in trichloroethane to prepare a 1Qwt% solution. Then apply this solution to a 25 μm thick polyethylene prephthalate film and dry to form a 17 μm thick photosensitive dry film layer. Furthermore, a polyethylene film having a thickness of 35 μm is laminated on the surface of this photosensitive dry film layer. Next, using this laminate film, first, the photosensitive dry film is attached to the adhesive layer 2 while peeling off the polyethylene film. In this state, using a circuit negative film with a line-space width of 75 μm, it is exposed to ultraviolet rays at an exposure dose of 18,011 J/cm.After exposure, the polyethylene prephthalate film is peeled off and heated at a temperature of 80° C. for 5 minutes. After heating, it is developed with a developer of 1.1.1 trichloroethane to form a permanent resist layer 4.
C)無電解鋼めっき処理 公知の無電解銅めっき法により厚さ 17μmの銅めっき層5を形成する。C) Electroless steel plating treatment Thickness determined by known electroless copper plating method A copper plating layer 5 of 17 μm is formed.
実施例2):
実施例1)において、感光性ドライフィルムを厚さ13
μmとし、厚さ10μmの銅めっき層5を形成する。Example 2): In Example 1), a photosensitive dry film with a thickness of 13
.mu.m, and a copper plating layer 5 having a thickness of 10 .mu.m is formed.
実施例3):
実施例1)において、感光性ドライフィルムを厚さ5μ
mとし、厚さ5μ汎の銅めっき層5を形成する。Example 3): In Example 1), a photosensitive dry film with a thickness of 5 μm was used.
m, and a copper plating layer 5 having a thickness of 5 μm is formed.
比較例1):
実施例1)において、感光性ドライフィルムとして厚さ
22μmの日立化成工業株式会社製5R−3000を用
い、厚さ22μ卯の銅めっき層を形成する。Comparative Example 1): In Example 1), a 22 μm thick 5R-3000 manufactured by Hitachi Chemical Co., Ltd. was used as the photosensitive dry film to form a 22 μm thick copper plating layer.
比較例2):
実施例1)において、感光性ドライフィルムの厚さを3
μmとし、厚さ3μ而の銅めつき層5を形成した。Comparative Example 2): In Example 1), the thickness of the photosensitive dry film was increased to 3
A copper plating layer 5 having a thickness of 3 μm was formed.
表
測定に用いた資料は各々20枚とする。表から明らかな
通り、本発明によれば銅降りはほとんど無く、生じたと
しても粒径が2〜3μmで問題なく、また、ショート不
良も比較例に比べて1/4以下となる。The number of materials used for table measurements shall be 20 each. As is clear from the table, according to the present invention, there is almost no copper precipitation, and even if it occurs, the particle size is 2 to 3 μm, causing no problem, and the number of short-circuit defects is 1/4 or less compared to the comparative example.
なお、実施例4)として、実施例1)において、感光性
ドライフィルムの厚さを15μ乳、銅めつき層5の厚さ
を13μmとしたものを用い、比較例1)と比較し解像
度を調べた。その結果、前者はライン・スペース幅60
μ汎までのものを製造できたが、後者は製造できなかっ
た。In addition, as Example 4), in Example 1), the thickness of the photosensitive dry film was 15 μm and the thickness of the copper plating layer 5 was 13 μm, and the resolution was compared with Comparative Example 1). Examined. As a result, the former has a line space width of 60
Although it was possible to manufacture products up to the μ-range, the latter could not be manufactured.
(発明の効果)
以上の通り、本発明によれば、感光性ドライフィルムの
厚さをλリクシているために、yB置時間短縮でき、銅
降りやショート不良を防止して歩留りを向上しうるプリ
ント配線板が得られる。(Effects of the Invention) As described above, according to the present invention, since the thickness of the photosensitive dry film is set to λ, the yB placement time can be shortened, copper dropout and short circuit defects can be prevented, and the yield can be improved. A printed wiring board is obtained.
図は本発明実施例の断面図を示す。
1・・・絶縁基板、4・・・感光性ドライフィルム、4
・・・銅めっき層。
特許出願人 日立コンデンナ株式会社
手続補正内(自発)The figure shows a cross-sectional view of an embodiment of the invention. 1... Insulating substrate, 4... Photosensitive dry film, 4
...Copper plating layer. Patent applicant: Hitachi Condenna Co., Ltd. Procedural amendment (voluntary)
Claims (1)
ジスト層とし、無電解めっき法により回路を形成するプ
リント配線板において、感光性ドライフィルムの厚さが
5〜20μmであることを特徴とするプリント配線板。(1) In a printed wiring board in which a photosensitive dry film is made into a permanent resist layer by exposure to ultraviolet rays and a circuit is formed by electroless plating, the printed wiring is characterized in that the thickness of the photosensitive dry film is 5 to 20 μm. Board.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP26622487A JPH01109792A (en) | 1987-10-23 | 1987-10-23 | Printed wiring board |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP26622487A JPH01109792A (en) | 1987-10-23 | 1987-10-23 | Printed wiring board |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH01109792A true JPH01109792A (en) | 1989-04-26 |
Family
ID=17427989
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP26622487A Pending JPH01109792A (en) | 1987-10-23 | 1987-10-23 | Printed wiring board |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH01109792A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160313641A1 (en) * | 2015-04-21 | 2016-10-27 | Fujifilm Electronic Materials U.S.A., Inc. | Photosensitive polyimide compositions |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5912434A (en) * | 1982-07-13 | 1984-01-23 | Tokyo Ohka Kogyo Co Ltd | Manufacture of printed wiring board |
-
1987
- 1987-10-23 JP JP26622487A patent/JPH01109792A/en active Pending
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5912434A (en) * | 1982-07-13 | 1984-01-23 | Tokyo Ohka Kogyo Co Ltd | Manufacture of printed wiring board |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160313641A1 (en) * | 2015-04-21 | 2016-10-27 | Fujifilm Electronic Materials U.S.A., Inc. | Photosensitive polyimide compositions |
US10036952B2 (en) | 2015-04-21 | 2018-07-31 | Fujifilm Electronic Materials U.S.A., Inc. | Photosensitive polyimide compositions |
US11782344B2 (en) | 2015-04-21 | 2023-10-10 | Fujifilm Electronic Materials U.S.A., Inc. | Photosensitive polyimide compositions |
US11899364B2 (en) | 2015-04-21 | 2024-02-13 | Fujifilm Electronic Materials U.S.A., Inc. | Photosensitive polyimide compositions |
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