JPH0361357B2 - - Google Patents
Info
- Publication number
- JPH0361357B2 JPH0361357B2 JP56080750A JP8075081A JPH0361357B2 JP H0361357 B2 JPH0361357 B2 JP H0361357B2 JP 56080750 A JP56080750 A JP 56080750A JP 8075081 A JP8075081 A JP 8075081A JP H0361357 B2 JPH0361357 B2 JP H0361357B2
- Authority
- JP
- Japan
- Prior art keywords
- multilayer printed
- printed board
- pressure
- minutes
- microwave
- 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.)
- Expired - Lifetime
Links
- 239000000758 substrate Substances 0.000 claims description 30
- 238000000034 method Methods 0.000 claims description 24
- 238000004519 manufacturing process Methods 0.000 claims description 12
- 238000010438 heat treatment Methods 0.000 claims description 9
- 239000000853 adhesive Substances 0.000 claims description 8
- 230000001070 adhesive effect Effects 0.000 claims description 8
- 230000010355 oscillation Effects 0.000 claims description 5
- 238000010030 laminating Methods 0.000 claims description 2
- 239000012780 transparent material Substances 0.000 claims description 2
- 239000010410 layer Substances 0.000 description 50
- 239000000463 material Substances 0.000 description 28
- 230000000052 comparative effect Effects 0.000 description 13
- 239000011521 glass Substances 0.000 description 10
- 239000004744 fabric Substances 0.000 description 9
- 239000011347 resin Substances 0.000 description 9
- 229920005989 resin Polymers 0.000 description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 6
- 239000011889 copper foil Substances 0.000 description 6
- -1 polyethylene Polymers 0.000 description 6
- 229920001721 polyimide Polymers 0.000 description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000004642 Polyimide Substances 0.000 description 4
- 239000004593 Epoxy Substances 0.000 description 3
- 238000007772 electroless plating Methods 0.000 description 3
- 239000003822 epoxy resin Substances 0.000 description 3
- 238000005530 etching Methods 0.000 description 3
- 239000000155 melt Substances 0.000 description 3
- 229920000647 polyepoxide Polymers 0.000 description 3
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 3
- 239000004810 polytetrafluoroethylene Substances 0.000 description 3
- 239000004698 Polyethylene Substances 0.000 description 2
- 238000005553 drilling Methods 0.000 description 2
- 238000005485 electric heating Methods 0.000 description 2
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical compound C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229920006113 non-polar polymer Polymers 0.000 description 2
- 229920000573 polyethylene Polymers 0.000 description 2
- 239000009719 polyimide resin Substances 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 230000002265 prevention Effects 0.000 description 2
- 239000010453 quartz Substances 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229920002367 Polyisobutene Polymers 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009713 electroplating Methods 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 238000011417 postcuring Methods 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B15/00—Layered products comprising a layer of metal
- B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
- B32B27/322—Layered products comprising a layer of synthetic resin comprising polyolefins comprising halogenated polyolefins, e.g. PTFE
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B15/00—Layered products comprising a layer of metal
- B32B15/20—Layered products comprising a layer of metal comprising aluminium or copper
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
- B32B27/302—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B38/00—Ancillary operations in connection with laminating processes
- B32B38/0008—Electrical discharge treatment, e.g. corona, plasma treatment; wave energy or particle radiation
-
- 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
- H05K3/46—Manufacturing multilayer circuits
- H05K3/4611—Manufacturing multilayer circuits by laminating two or more circuit boards
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2250/00—Layers arrangement
- B32B2250/42—Alternating layers, e.g. ABAB(C), AABBAABB(C)
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2310/00—Treatment by energy or chemical effects
- B32B2310/08—Treatment by energy or chemical effects by wave energy or particle radiation
- B32B2310/0806—Treatment by energy or chemical effects by wave energy or particle radiation using electromagnetic radiation
- B32B2310/0862—Treatment by energy or chemical effects by wave energy or particle radiation using electromagnetic radiation using microwave
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2311/00—Metals, their alloys or their compounds
- B32B2311/24—Aluminium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2318/00—Mineral based
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2323/00—Polyalkenes
- B32B2323/04—Polyethylene
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2323/00—Polyalkenes
- B32B2323/10—Polypropylene
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2325/00—Polymers of vinyl-aromatic compounds, e.g. polystyrene
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2327/00—Polyvinylhalogenides
- B32B2327/12—Polyvinylhalogenides containing fluorine
- B32B2327/18—PTFE, i.e. polytetrafluoroethylene
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2457/00—Electrical equipment
- B32B2457/08—PCBs, i.e. printed circuit boards
-
- 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
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/06—Lamination
- H05K2203/068—Features of the lamination press or of the lamination process, e.g. using special separator sheets
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Thermal Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Production Of Multi-Layered Print Wiring Board (AREA)
Description
本発明は、内層ボイドがなく、内層パターンの
ずれが少ない、高信頼性の多層プリント板を、短
時間で製造する方法に関する。
多層プリント板は、エポキシ−ガラスクロス系
又はポリイミド−ガラスクロス系等の銅張り積層
板に、エツチング等の処理を施して導電層パター
ンを形成するか、あるいはエポキシ−ガラスクロ
ス系又はポリイミド−ガラスクロス系等の積層板
に、無電解めつきによつて導電層パターンを形成
したものを基板とし、これらの基板と、ガラスク
ロスに熱硬化性樹脂を含浸させて半硬化状態にし
たプリプレグの接着シートとを交互に重ね合せ、
治具板を介してプレスに挿入し、加熱圧着して製
造する。プレスは、電熱式のものも用いるが、通
常は水蒸気プレスを用いる場合が多い。
電熱又は水蒸気加熱方式のプレスによる多層プ
リント板の製造方法の欠点の1つに、治具板の反
りの問題がある。
加熱されたプレスの熱盤上に治具板を置くと、
熱盤に接触した面が膨張して、治具板は、熱盤と
反対側へ反り返る。したがつて、上下を2枚の治
具板ではさまれた多層プリント板は、中央が膨ら
んだ状態になる。この治具板の反りが矯正される
ためには、極めて高い圧力が必要であり、30〜40
Kg/cm2の圧力でも充分とはいえない。そのため、
加熱圧着後の多層プリント板は、中央部と端部で
は厚さが若干異なるものになる。
これは、内層の導電層間の絶縁層の厚さに差が
生じ、インピーダンス等の電気的特性を不良にす
る。また、治具板が反り返つた状態で加圧された
場合、中央部の圧力は必要以上に低下するため、
内層ボイドが発生しやすい。更に、内層基板に加
わる圧力が不均一なため、異常な変形が生じ、結
果的に層間のパターンのずれの原因となる。これ
らは、多層プリント板として重大な欠点である。
治具板の反りを矯正するために圧力を上げる
と、内層基板の局所的な変形が大きくなり、圧力
を下げると内層ボイドが発生する。
したがつて、8〜10層のような多層プリント板
を製造する場合、例えば電源層パターンやアース
層パターンを形成した基板を接着して、これを1
次接着とし、次いで、このものと位置合せを行い
ながら信号層パターン形成の基板を、その外側に
2次接着するか、あるいはプリプレグと銅箔とを
2次接着し、銅箔に信号層パターンを形成し、そ
の上に更に銅箔とプリプレグを3次接着する等の
方法を講じる。こうすることによつて、内層パタ
ーンのずれを少しでも小さくする訳である。
エポキシ系樹脂は、完全に硬化するためには、
130℃〜140℃で15〜20分間、その後170℃〜180℃
で50〜70分間の加熱を必要とするから、1次接
着、2次接着を合せて、通常、100〜120分間を必
要とする。この作業時間の長いことが、第2の、
そして最大の欠点である。
ポリイミド系樹脂も、最近はエポキシ系と同じ
硬化条件で硬化するプリプレグも市販されている
が、一般には、後硬化を必要とするから、前記の
作業時間の2〜3倍が必要となる。
本発明は、これらの欠点を改善するためになさ
れたものであり、内層ボイドがなく、層間ずれが
少ない、信頼性の高い多層プリント板を、短時間
で製造する方法を提供するものである。
本発明を概説すれば、本発明は、基板と、未硬
化状態の、プリプレグとなる接着シートとを交互
に重ね合せて得られる構成品を、加圧加熱して多
層プリント板を製造する方法において、該構成品
の加圧加熱を、マイクロ波発振装置を内蔵した加
圧装置によつて行うことを特徴とする、多層プリ
ント板の製造方法である。
すなわち本発明は、基板と接着シートとを交互
に重ね合せてなる構成品を加圧加熱する場合に、
従来の電熱又は蒸気加熱の加圧装置を用いる代り
に、マイクロ波発振装置を内蔵した加圧装置を用
いることを特徴とする。そして、それに伴い、該
構成品中にマイクロ波が浸透するように、マイク
ロ波不透過性の基板、例えば電源層又はアース層
を形成した基板の位置を工夫し、また治具板等の
材質を選定したものである。
本発明において使用するマイクロ波発振装置の
波長は、300MHz〜30000MHzであり、900MHz付
近が好適である。
この構成例を、以下図面に従つて説明する。
第1図は、本発明における基板と接着シートか
らなる構成品の重ね合せ方の一例を示す縦断面図
である。
第1図において、1は信号層基板、2は電源層
又はアース層基板、3はプリプレグを示す。
すなわち、第1図は、電源層又はアース層を形
成したマイクロ波不透過性の基板が、内部に配置
された例を示したものである。該基板は、本発明
においては、内部でなく、いずれか一方の外側に
あつてもよく、その場合には、反対側からマイク
ロ波が浸透するので差支えない。すなわち、該基
板が両外側を占めるようなことがなければよい。
次に、この構成品を、加圧加熱する装置内での
配置例を第2図に示す。
第2図は、前記構成品を、本発明により加圧加
熱する場合における各部材の配置例を示す縦断面
図である。
第2図において、4は上部ボルスター、5は下
部ボルスター、6はマイクロ波発振装置、7は加
圧板、8は加圧加熱すべき構成品、9は治具板、
10は歯型の高周波漏れ防止板を示す。
本発明において、治具板9として用いるもの
は、マイクロ波透過性の物質であることを必要と
する。
これらの物質は、従来マイクロ波発振装置を用
いる場合に使用されている周知の物質でよい。
そのような物質としては、例えば、ポリエチレ
ン、ポリスチレン、ポリイソブチレン、ポリ四フ
ツ化エチレン又はポリプロピレン等に代表され
る、無極性の高分子重合体、あるいは、例えば、
石英、結晶性アルミナ、ほう硝酸ガラス等に代表
される、誘電損失の小さな物質がある。
マイクロ波発振装置を内蔵した加圧装置の被加
圧物と接する加圧板7の材料も、マイクロ波透過
性の物質、例えば前記の無極性の高分子重合体、
又は誘電損失の小さな物質で構成される。この場
合、治具板9を省略することもできる。
マイクロ波のエネルギーが物体に吸収されて次
第に減衰する程度を、電力が半減する距離、すな
わち、電力半減深度Dで表わすと、下記(1)式のよ
うになる。
(1)式において、ε0真空誘電率、μ0は透磁率、ω
は角速度であつて、ω=2πで表わされる。tanδ
≪1であれば、ε0=1/4π×9×109(F/m)、μ0
=4π×10-7(H/m)を(1)式に代入して、近似的
に下記(2)式が得られる。
(2)式において、εrは比誘電率である。
電力半減深度Dは√とtanδの積、すなわち誘
電損失に関する定数に反比例するから、ポリ四フ
ツ化エチレン、ポリエチレン及び石英などは、周
波数が400MHz以上では、Dが300m以上になり、
実際上、マイクロ波に対してほぼ透明であるとい
える。したがつて、治具板9及び/又は加圧板7
は、いくら厚くても良い。本発明では、上式に基
づいて、誘電損失の小さい、マイクロ波透過性の
物質を選定すればよい。
加圧加熱後、構成品は除圧し、冷却する。
なお、多層プリント板としては、この後、スル
ーホールをあけ、無電解めつき、又は無電解めつ
き+電解めつきによつてスルーホール内及び外層
パターンを形成して完成するが、本明細書では、
スルーホール工程以後を省略し、この工程前のも
のを、多層プリント板と称する。
以下、実施例に基づいて本発明を例証するが、
本発明はこれらに限定されるものではない。
実施例 1
エポキシ−ガラスクロス系の銅張り積層板とし
て、日立化成工業製のMCL−E608(登録商標)
で、基材厚さ0.2mm、両面の銅箔の厚さがそれぞ
れ70μmのものをエツチング法で処理して、電源
層及びアース層のパターンを形成した。同じく、
基材厚さ0.2mm、銅箔厚さ70μmの片面銅箔の積層
板MCL−E608を、エツチング法で処理して片面
に信号層パターンを形成した。
まず、電源層及びアース層パターンの基板2の
2枚を、日立化成工業製のエポキシ−ガラスクロ
ス系ブリプレグGEA−608N3(登録商標)で0.1mm
厚さのもの2枚を介して挟み、0.5mm厚さの鉄製
治具板で固定した後、蒸気プレスを用いて積層接
着した。なお、用いたブリプレグの樹脂を、130
℃一定温度で測定したときの最低粘度は、250ポ
イズであつた。
接着条件は、圧力30Kg/cm2、温度130℃で15分
間、次いで170℃で15分間である。
次いで、このものを中央に配置して、それぞれ
0.1mm厚さのブリプレグGEA−608N(130℃におけ
る最低粘度250ポイズ)の3枚を介して、片面に
信号層パターンを形成した前記基板1を両側から
配置し、第1図に示したような構成にする。
次に、この構成品を、本発明に従つて、5mm厚
さのポリ四化フツ化エチレン製の治具板9で固定
して、マイクロ波発振装置6を内蔵した加圧装置
に挿入した。その後、4Kg/cm2に加圧し、915M
Hzのマイクロ波を照射した。2分後、圧力を30
Kg/cm2に上げ、マイクロ波は照射を続け、全照射
時間15分後に照射を停止した。同時に圧力を解放
し、積層接着された構成品8を、治具板9と共に
水冷プレスにおいて10Kg/cm2で10分間加圧冷却さ
れた。結果は、まとめて表示する。
実施例 2
実施例1と同じ材料及び同じ手順で多層プリン
ト板を製作した。但し、加圧装置における条件
は、4Kg/cm2で2分間+20Kg/cm2で13分間であ
る。そして、マイクロ波照射は、915MHzで15分
間である。
実施例 3
実施例1と同じ材料及び同じ手順で多層プリン
ト板を製作した。但し、加圧装置での条件は、2
Kg/cm2で2分間+10Kg/cm2で13分間である。
実施例 4
実施例1と同じ銅張り積層板を用い、同じ手順
で多層プリント板を製作した。但し、電源層及び
アース層パターンを形成した基板2枚を蒸気プレ
スで接着した場合に使用した、プリプレグ樹脂の
130℃における最低粘度は250ボイズであり、ま
た、この積層接着品を、信号層パターンを形成し
た基板と重ね合せ、実施例1に記載の方法で、加
圧装置内において加圧した場合に使用したプリプ
レグ樹脂の130℃における最低粘度は400ポイズで
ある。そして、915MHzのマイクロ波照射中の加
圧条件は、2Kg/cm2で2分間+10Kg/cm2で13分間
である。
実施例 5
電源層及びアース層パターンを形成した基板を
蒸気プレスで接着した場合に使用したプリプレグ
樹脂の130℃における最低粘度は250ポイズであ
り、またこの積層接着品を、信号層パターンを形
成した基板と重ね合せ、加圧装置内で加圧した場
合に使用したプリプレグ樹脂の130℃における最
低粘度は80ポイズであり、その他の条件は、実施
例4と同じ条件で多層プリント板を製作した。
実施例 6
基板材料としては、日立化成工業製のポリイミ
ド−ガラスクロス系銅張り積層板MCL−I67(登
録商標)を用い、またプリプレグ材料として日立
化成工業製のポリイミド−ガラスクロス系プリプ
レグGIA−67N(登録商標)を用いた以外は、プ
リプレグ樹脂の粘度、手順その他を実施例3と全
く同じ方法で多層プリント板を製作した。なお、
GIA−67Nは、エポキシ系と同じ硬化条件で硬化
する、ポリイミド樹脂系プリプレグである。
比較例 1
実施例1と同じ材料と方法によつて電源層及び
アース層パターン基板を作り、これを、実施例1
と同じプリプレグと方法を用いて蒸気プレスで積
層接着した。次に、実施例1と同じ材料及び方法
を用いて、信号層パターンを形成した基板を作
り、それと、前記の電源層及びアース層パターン
の積層接着物とを、実施例1と同じく第1図に示
すように配置し、これを本発明の実施例とは異な
り、厚さ5mmの鉄製治具板で固定し、蒸気プレス
で加圧加熱して多層プリント板を製作した。加圧
条件は、4Kg/cm2で6分間+30Kg/cm2で85分間で
あり、温度条件は、130℃で15分間+170℃で60分
間である。その後、同一プレスで10分間冷却し
た。結果は、まとめて後で表示する。
比較例 2
比較例1と同じ材料及び同じ手順で多層プリン
ト板を製作した。但し、加圧条件は、4Kg/cm2で
6分間+20Kg/cm2で85分間である。
比較例 3
比較例3と同じ材料及び同じ手順で多層プリン
ト板を製作した。但し、加圧条件は、2Kg/cm2で
6分間+10Kg/cm2で85分間である。
比較例 4
実施例4と全く同じ特性をもつ同じ材料を用い
て、比較例3と同じ手順及び同じ加圧条件で多層
プリント板を製作した。
比較例 5
実施例5と全く同じ特性をもつ同じ材料を用い
て、比較例3と同じ手順及び同じ加圧条件で多層
プリント板を製作した。
比較例 6
実施例6と全く同じ特性をもつ同じ材料を用い
て、比較例3と同じ手順及び同じ加圧条件で多層
プリント板を製作した。
以上各例の結果を、まとめて下記表に示す。
The present invention relates to a method of manufacturing a highly reliable multilayer printed board without inner layer voids and with little deviation of inner layer patterns in a short time. Multilayer printed boards are produced by forming a conductive layer pattern on a copper-clad laminate made of epoxy-glass cloth or polyimide-glass cloth by performing etching or other processing, or by forming a conductive layer pattern on a copper-clad laminate made of epoxy-glass cloth or polyimide-glass cloth. The substrate is a laminate such as a laminate with a conductive layer pattern formed by electroless plating, and an adhesive sheet made of these substrates and a prepreg made by impregnating glass cloth with a thermosetting resin to a semi-cured state. Alternately overlap the
It is manufactured by inserting it into a press via a jig plate and heat-pressing it. Although an electrically heated press is also used, a steam press is usually used. One of the drawbacks of the method of manufacturing multilayer printed boards using electric heating or steam heating presses is the problem of warpage of the jig plate. When the jig plate is placed on the hot plate of the heated press,
The surface in contact with the hot platen expands, and the jig plate warps toward the side opposite to the hot platen. Therefore, the multilayer printed board whose upper and lower sides are sandwiched between two jig plates has a bulged center. In order to correct the warpage of this jig plate, extremely high pressure is required, and the
Even a pressure of Kg/cm 2 is not sufficient. Therefore,
After heat and pressure bonding, the multilayer printed board will have a slightly different thickness at the center and at the edges. This causes a difference in the thickness of the insulating layer between the inner conductive layers, resulting in poor electrical characteristics such as impedance. Also, if the jig plate is pressurized in a warped state, the pressure in the center will drop more than necessary, so
Inner layer voids are likely to occur. Furthermore, since the pressure applied to the inner layer substrate is non-uniform, abnormal deformation occurs, resulting in misalignment of patterns between layers. These are serious drawbacks for multilayer printed boards. When the pressure is increased to correct the warpage of the jig plate, local deformation of the inner layer substrate increases, and when the pressure is lowered, inner layer voids occur. Therefore, when manufacturing a multilayer printed board with 8 to 10 layers, for example, a board on which a power layer pattern and a ground layer pattern are formed is bonded and
Then, while aligning with this substrate, the substrate with the signal layer pattern formed thereon is secondarily bonded to the outside thereof, or the prepreg and copper foil are secondarily bonded and the signal layer pattern is formed on the copper foil. After that, a method such as tertiary bonding of copper foil and prepreg is used. By doing this, the deviation of the inner layer pattern is made as small as possible. In order for epoxy resin to be completely cured,
130℃~140℃ for 15~20 minutes, then 170℃~180℃
Since heating for 50 to 70 minutes is required, the total time for primary adhesion and secondary adhesion is usually 100 to 120 minutes. The second reason is that this long work time is
And this is the biggest drawback. Polyimide resins and prepregs that cure under the same curing conditions as epoxy resins have recently been commercially available, but they generally require post-curing, which requires two to three times the working time described above. The present invention has been made to improve these drawbacks, and provides a method for manufacturing a highly reliable multilayer printed board in a short time, with no inner layer voids and little interlayer misalignment. To summarize the present invention, the present invention provides a method for producing a multilayer printed board by heating and pressurizing a component obtained by alternately stacking a substrate and an uncured adhesive sheet serving as a prepreg. , a method for manufacturing a multilayer printed board, characterized in that the component is heated under pressure using a pressure device incorporating a microwave oscillation device. That is, in the present invention, when pressing and heating a component made by laminating substrates and adhesive sheets alternately,
Instead of using a conventional electric heating or steam heating pressurizing device, a pressurizing device with a built-in microwave oscillation device is used. Along with this, in order to allow microwaves to penetrate into the component, the position of the microwave-impermeable substrate, such as the substrate on which the power supply layer or the ground layer is formed, should be devised, and the material of the jig plate etc. should be changed. This is the selected one. The wavelength of the microwave oscillation device used in the present invention is 300 MHz to 30000 MHz, preferably around 900 MHz. This configuration example will be explained below with reference to the drawings. FIG. 1 is a longitudinal cross-sectional view showing an example of how components made of a substrate and an adhesive sheet are stacked together in the present invention. In FIG. 1, 1 is a signal layer substrate, 2 is a power layer or earth layer substrate, and 3 is a prepreg. That is, FIG. 1 shows an example in which a microwave-impermeable substrate on which a power supply layer or a ground layer is formed is placed inside. In the present invention, the substrate may be located on the outside of one of the substrates instead of the inside, and in that case, there is no problem because the microwave will penetrate from the opposite side. That is, it is sufficient that the substrate does not occupy both outer sides. Next, FIG. 2 shows an example of the arrangement of this component in an apparatus for pressurizing and heating. FIG. 2 is a longitudinal sectional view showing an example of the arrangement of each member when the component is pressurized and heated according to the present invention. In FIG. 2, 4 is an upper bolster, 5 is a lower bolster, 6 is a microwave oscillator, 7 is a pressure plate, 8 is a component to be pressurized and heated, 9 is a jig plate,
10 indicates a tooth-shaped high frequency leakage prevention plate. In the present invention, what is used as the jig plate 9 needs to be a material that is transparent to microwaves. These materials may be well-known materials that have been used in conventional microwave oscillation devices. Examples of such substances include non-polar polymers such as polyethylene, polystyrene, polyisobutylene, polytetrafluoroethylene, and polypropylene;
There are materials with low dielectric loss, such as quartz, crystalline alumina, and boronitrate glass. The material of the pressure plate 7 that comes into contact with the pressurized object of the pressure device with a built-in microwave oscillator is also a microwave-transparent substance, such as the above-mentioned non-polar polymer,
Or made of a material with low dielectric loss. In this case, the jig plate 9 can also be omitted. The degree to which microwave energy is absorbed by an object and gradually attenuated is expressed by the distance at which the power is halved, that is, the power halving depth D, as shown in equation (1) below. In equation (1), ε 0 is the vacuum permittivity, μ 0 is the magnetic permeability, and ω
is the angular velocity and is expressed as ω=2π. tanδ
If ≪1, ε 0 = 1/4π×9×10 9 (F/m), μ 0
By substituting =4π×10 -7 (H/m) into equation (1), the following equation (2) can be approximately obtained. In equation (2), ε r is the relative dielectric constant. Since the power half-life depth D is inversely proportional to the product of √ and tanδ, that is, the constant related to dielectric loss, for polytetrafluoroethylene, polyethylene, quartz, etc., when the frequency is 400 MHz or more, D is 300 m or more,
In fact, it can be said that it is almost transparent to microwaves. Therefore, the jig plate 9 and/or the pressure plate 7
It doesn't matter how thick it is. In the present invention, a microwave-transparent material with small dielectric loss may be selected based on the above formula. After pressurizing and heating, the components are depressurized and cooled. The multilayer printed board is then completed by drilling through holes and forming patterns inside and outside the through holes by electroless plating or electroless plating + electrolytic plating. So,
The steps after the through-hole step are omitted, and the board before this step is referred to as a multilayer printed board. The present invention will be illustrated below based on Examples.
The present invention is not limited to these. Example 1 MCL-E608 (registered trademark) manufactured by Hitachi Chemical Co., Ltd. was used as an epoxy-glass cloth copper-clad laminate.
Then, a base material with a thickness of 0.2 mm and a copper foil on both sides with a thickness of 70 μm was processed using an etching method to form patterns for a power layer and a ground layer. Similarly,
A single-sided copper foil laminate MCL-E608 with a base material thickness of 0.2 mm and a copper foil thickness of 70 μm was processed by an etching method to form a signal layer pattern on one side. First, the two substrates 2 with the power layer and earth layer patterns are made of epoxy-glass cloth Bripreg GEA-608N3 (registered trademark) manufactured by Hitachi Chemical Co., Ltd. with a thickness of 0.1 mm.
After sandwiching two sheets of thick material through each other and fixing them with a 0.5 mm thick iron jig plate, they were laminated and bonded using a steam press. In addition, the resin of Buripreg used was 130
The minimum viscosity measured at a constant temperature of 250 poise was 250 poise. The bonding conditions were a pressure of 30 Kg/cm 2 and a temperature of 130° C. for 15 minutes, followed by 170° C. for 15 minutes. Then place this thing in the center and each
The substrate 1 with a signal layer pattern formed on one side was placed from both sides through three sheets of Bripreg GEA-608N (minimum viscosity 250 poise at 130°C) with a thickness of 0.1 mm, as shown in Fig. 1. Configure. Next, in accordance with the present invention, this component was fixed with a jig plate 9 made of polytetrafluoroethylene having a thickness of 5 mm, and inserted into a pressurizing device containing a microwave oscillator 6. After that, it was pressurized to 4Kg/cm 2 and 915M
Hz microwave was irradiated. After 2 minutes, reduce the pressure to 30
Kg/cm 2 , microwave irradiation continued, and irradiation was stopped after a total irradiation time of 15 minutes. At the same time, the pressure was released, and the laminated and bonded component 8 was cooled under pressure at 10 kg/cm 2 for 10 minutes together with the jig plate 9 in a water-cooled press. Results will be displayed together. Example 2 A multilayer printed board was manufactured using the same materials and procedures as in Example 1. However, the conditions in the pressurizing device are 4 Kg/cm 2 for 2 minutes + 20 Kg/cm 2 for 13 minutes. And microwave irradiation is 915MHz for 15 minutes. Example 3 A multilayer printed board was manufactured using the same materials and procedures as in Example 1. However, the conditions for the pressurizing device are 2.
Kg/cm 2 for 2 minutes + 10Kg/cm 2 for 13 minutes. Example 4 A multilayer printed board was produced using the same copper-clad laminate as in Example 1 and following the same procedure. However, the prepreg resin used when bonding the two substrates with the power layer and earth layer patterns formed using a steam press
The minimum viscosity at 130°C is 250 voids, and when this laminated adhesive product is laminated with a substrate on which a signal layer pattern is formed and pressurized in a pressurizing device by the method described in Example 1, it can be used. The minimum viscosity of the prepared prepreg resin at 130°C is 400 poise. The pressurizing conditions during the 915 MHz microwave irradiation were 2 Kg/cm 2 for 2 minutes + 10 Kg/cm 2 for 13 minutes. Example 5 The minimum viscosity at 130°C of the prepreg resin used when bonding the substrates on which the power layer and earth layer patterns were formed using a steam press was 250 poise. A multilayer printed board was manufactured under the same conditions as Example 4, except that the prepreg resin used had a minimum viscosity of 80 poise at 130°C when laminated with a substrate and pressurized in a pressurizing device. Example 6 A polyimide-glass cloth copper-clad laminate MCL-I67 (registered trademark) manufactured by Hitachi Chemical Co., Ltd. was used as the substrate material, and a polyimide-glass cloth prepreg GIA-67N manufactured by Hitachi Chemical Co., Ltd. was used as the prepreg material. A multilayer printed board was manufactured in exactly the same manner as in Example 3, except that (registered trademark) was used, except for the viscosity of the prepreg resin, the procedure, and other aspects. In addition,
GIA-67N is a polyimide resin prepreg that cures under the same curing conditions as epoxy resins. Comparative Example 1 A power layer and earth layer pattern board was made using the same materials and methods as in Example 1, and this was used as Example 1.
Laminated and bonded using a steam press using the same prepreg and method. Next, using the same materials and methods as in Example 1, a substrate with a signal layer pattern formed thereon was made, and the laminated adhesive of the power layer and earth layer patterns was bonded to it as in Example 1, as shown in FIG. They were arranged as shown in Figure 1, and unlike the examples of the present invention, they were fixed with a 5 mm thick iron jig plate and heated under pressure using a steam press to produce a multilayer printed board. Pressure conditions were 4 Kg/cm 2 for 6 minutes + 30 Kg/cm 2 for 85 minutes, and temperature conditions were 130°C for 15 minutes + 170°C for 60 minutes. Thereafter, it was cooled for 10 minutes in the same press. The results will be summarized and displayed later. Comparative Example 2 A multilayer printed board was manufactured using the same materials and the same procedure as Comparative Example 1. However, the pressurization conditions were 4 Kg/cm 2 for 6 minutes + 20 Kg/cm 2 for 85 minutes. Comparative Example 3 A multilayer printed board was manufactured using the same materials and the same procedure as Comparative Example 3. However, the pressurization conditions were 2 Kg/cm 2 for 6 minutes + 10 Kg/cm 2 for 85 minutes. Comparative Example 4 A multilayer printed board was manufactured using the same material with exactly the same characteristics as in Example 4, using the same procedure and under the same pressure conditions as in Comparative Example 3. Comparative Example 5 A multilayer printed board was manufactured using the same material with exactly the same characteristics as in Example 5, using the same procedure and under the same pressure conditions as in Comparative Example 3. Comparative Example 6 A multilayer printed board was manufactured using the same material with exactly the same characteristics as in Example 6, using the same procedure and under the same pressure conditions as in Comparative Example 3. The results of each example above are summarized in the table below.
【表】【table】
【表】
内層ボイドは、プリプレグ樹脂の溶融粘度と圧
力とによつて発生したり消えたりする。その意味
で、従来の製造方法に準じた比較例は、ボイドが
発生しない溶融粘度(130℃における最低粘度)
の範囲が狭く、20Kg/cm2以上の高圧力でなければ
ならないが、本発明の実施例では、高圧力はもち
ろんのこと、10Kg/cm2のような低圧力でもボイド
は発生せず、また、プリプレグ樹脂の溶融粘度も
広い範囲でボイドが発生しない。これはエポキシ
系材料のみならず、ポリイミド系材料を用いた場
合でも同じである。
スルーホールをあける際のドリル位置に対する
層間の最大ずれは、圧力が高い程大きい傾向にあ
り、ポリイミド系材料よりもエポキシ系材料の方
が大きい値を示している。しかし、その場合も、
本発明の実施例の方がずれの量は小さく、本発明
の方法が、内層基板に対して安定な方法であるこ
とが認められる。
本発明方法の最も大きな効果は、作業時間の短
縮である。比較例では、電源層及びアース層パタ
ーンを形成した基板の1次接着も含め、全積層接
着時間として、エポキシ系材料では105分、ポリ
イミド系材料では115分を要した。それに対して、
本発明の実施例において、エポキシ系材料では45
分、ポリイミド系材料では50分で終了した。これ
は、従来の半分以下の作業時間に短縮されたこと
を実証するものである。すなわち本発明が、多層
プリント板の製造方法として優れた方法であるこ
とが実証された。[Table] Inner layer voids occur or disappear depending on the melt viscosity and pressure of the prepreg resin. In that sense, the comparative example according to the conventional manufacturing method has a melt viscosity that does not generate voids (minimum viscosity at 130℃)
However, in the embodiments of the present invention, voids do not occur not only at high pressures but also at low pressures such as 10 kg/cm 2 . , the melt viscosity of the prepreg resin can be varied over a wide range without causing voids. This applies not only to epoxy materials but also to polyimide materials. The maximum deviation between layers relative to the drill position when drilling a through hole tends to be larger as the pressure is higher, and the epoxy material shows a larger value than the polyimide material. However, even in that case,
The amount of deviation is smaller in the example of the present invention, and it is recognized that the method of the present invention is a stable method for the inner layer substrate. The most significant effect of the method of the present invention is a reduction in working time. In the comparative example, the total lamination bonding time, including the primary bonding of the substrates on which the power layer and earth layer patterns were formed, was 105 minutes for the epoxy material and 115 minutes for the polyimide material. On the other hand,
In the embodiment of the present invention, 45
50 minutes for polyimide materials. This proves that the work time has been reduced to less than half of the conventional work time. That is, it was demonstrated that the present invention is an excellent method for producing a multilayer printed board.
第1図は、本発明における基板と接着シートか
らなる構成品の重ね合せ方の一例を示す縦断面図
である。第2図は、前記構成品を、本発明により
加圧加熱する場合における各部材の配置例を示す
縦断面図である。1:信号層基板、2:電源層又
はアース層基板、3:プリプレグ、4:上部ボル
スター、5:下部ボルスター、6:マイクロ波発
振装置、7:加圧板、8:加圧加熱すべき構成
品、9:治具板、10:歯型の高周波漏れ防止
板。
FIG. 1 is a longitudinal cross-sectional view showing an example of how components made of a substrate and an adhesive sheet are stacked together in the present invention. FIG. 2 is a longitudinal sectional view showing an example of the arrangement of each member when the component is pressurized and heated according to the present invention. 1: Signal layer board, 2: Power layer or earth layer board, 3: Prepreg, 4: Upper bolster, 5: Lower bolster, 6: Microwave oscillator, 7: Pressure plate, 8: Components to be pressurized and heated , 9: Jig plate, 10: Tooth-shaped high frequency leak prevention plate.
Claims (1)
ートとを交互に重ね合せて得られる構成品を、加
圧加熱して多層プリント板を製造する方法におい
て、該構成品の加圧加熱を、マイクロ波発振装置
を内蔵した加圧装置によつて行うことを特徴とす
る、多層プリント板の製造方法。 2 該構成品を、マイクロ波不透過性の基板が、
両外側を占めないように構成する、特許請求の範
囲第1項に記載の多層プリント板の製造方法。 3 該加圧装置における治具板及び/又は加圧板
が、マイクロ波透過性の物質である、特許請求の
範囲第1項又は第2項に記載の多層プリント板の
製造方法。[Claims] 1. A method for producing a multilayer printed board by pressurizing and heating a component obtained by alternately laminating a substrate and an uncured adhesive sheet called Buri Preg, in which the component is heated. A method for manufacturing a multilayer printed board, characterized in that pressure heating is performed using a pressure device having a built-in microwave oscillation device. 2. The component is made of a microwave-impermeable substrate,
The method for manufacturing a multilayer printed board according to claim 1, wherein the multilayer printed board is configured so as not to occupy both outer sides. 3. The method for manufacturing a multilayer printed board according to claim 1 or 2, wherein the jig plate and/or the pressure plate in the pressure device is made of a microwave-transparent material.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP56080750A JPS57196598A (en) | 1981-05-29 | 1981-05-29 | Method of producing multilayer printed board |
DE3220272A DE3220272C2 (en) | 1981-05-29 | 1982-05-28 | Method of forming a multilayer printed board |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP56080750A JPS57196598A (en) | 1981-05-29 | 1981-05-29 | Method of producing multilayer printed board |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS57196598A JPS57196598A (en) | 1982-12-02 |
JPH0361357B2 true JPH0361357B2 (en) | 1991-09-19 |
Family
ID=13727073
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP56080750A Granted JPS57196598A (en) | 1981-05-29 | 1981-05-29 | Method of producing multilayer printed board |
Country Status (2)
Country | Link |
---|---|
JP (1) | JPS57196598A (en) |
DE (1) | DE3220272C2 (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3423181A1 (en) * | 1984-06-22 | 1986-01-02 | Dielektra GmbH, 5000 Köln | METHOD FOR PRODUCING PRE-LAMINATES FOR MULTIPLE-LAYER PCB |
IL80277A0 (en) * | 1985-10-15 | 1987-01-30 | President Eng Corp | Process for the production of prepregs and metal-laminated base material for circuit boards,and apparatus for carrying out this process |
JPH0753420B2 (en) * | 1986-08-15 | 1995-06-07 | 松下電工株式会社 | Manufacturing method of multilayer printed wiring board |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS53145069A (en) * | 1977-05-24 | 1978-12-16 | Fujikura Ltd | Method of producing printed circuit board |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1188157B (en) * | 1961-04-21 | 1965-03-04 | Litton Industries Inc | Method of making a layered printed circuit board |
US3681171A (en) * | 1968-08-23 | 1972-08-01 | Hitachi Ltd | Apparatus for producing a multilayer printed circuit plate assembly |
US3720561A (en) * | 1970-01-20 | 1973-03-13 | Crain R Ltd | Process for producing manifolded forms |
NL166171C (en) * | 1971-06-07 | 1981-01-15 | Hollandse Signaalapparaten Bv | METHOD FOR MANUFACTURING MULTIPLE LAYER PRINTED CIRCUITS AND DEVICE FOR REALIZING THIS METHOD |
DE2717286C3 (en) * | 1977-04-19 | 1980-02-21 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Method of manufacturing a multilayer printed circuit board |
-
1981
- 1981-05-29 JP JP56080750A patent/JPS57196598A/en active Granted
-
1982
- 1982-05-28 DE DE3220272A patent/DE3220272C2/en not_active Expired
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS53145069A (en) * | 1977-05-24 | 1978-12-16 | Fujikura Ltd | Method of producing printed circuit board |
Also Published As
Publication number | Publication date |
---|---|
DE3220272A1 (en) | 1983-01-05 |
DE3220272C2 (en) | 1984-04-26 |
JPS57196598A (en) | 1982-12-02 |
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