PRINTED WIRING BOARD AND MANUFACTURING METHOD OF THE SAME

• Main Authors: ADACHI TAKEMA, FURUSAWA TAKESHI, NAKAMURA WATARU
• Format: Patent
• Language: English; Japanese
• Published: 30.05.2016
• Subjects: CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS; PRINTED CIRCUITS

PROBLEM TO BE SOLVED: To improve connection reliability between a pad and a solder bump and release strain based on a difference between thermal expansion coefficients of a semiconductor element and a printed wiring board.SOLUTION: A printed wiring board comprises: a resin insulation layer 11 having a first surface 11a and a second surface 11b; a first conductor layer 12 which is formed on the first surface 11a side of the resin insulation layer 11 and includes pads 12c for mounting an electronic component and a wiring pattern 12b; and a second conductor layer 14 formed on the second surface 11b of the resin insulation layer 11. The pad 12c is composed of a base part 12c1 embedded in the resin insulation layer 11 and a post part 12c2 projecting from the resin insulation layer 11, and a width d of the post part 12c2 is smaller than a width w of the base part 12c1 and a surface of the base part 12c1 on the post 12c2 side is flush with the first surface 11a of the resin insulation layer 11. The pad 12c is an electric plated film where the base part 12c1 and the post part 12c2 are integrally formed.SELECTED DRAWING: Figure 1 【課題】パッドとハンダバンプとの接続の信頼性の向上、および、半導体素子とプリント配線板との熱膨張係数の差に基づく応力の緩和。【解決手段】第１面１１ａ、および第２面１１ｂを有する樹脂絶縁層１１の第１面１１ａ側に電子部品を搭載するためのパッド１２ｃおよび配線パターン１２ｂを含む第１導体層１２が形成され、樹脂絶縁層１１の第２面１１ｂに第２導体層１４が形成されている。そして、パッド１２ｃは、樹脂絶縁層１１内に埋め込まれるベース部１２ｃ１と樹脂絶縁層１１から突出しているポスト部１２ｃ２とからなると共に、ポスト部１２ｃ２の幅ｄはベース部１２ｃ１の幅ｗより小さく、かつ、ベース部１２ｃ１のポスト１２ｃ２側の面が樹脂絶縁層１１の第１面１１ａと面一であり、パッド１２ｃは、ベース部１２ｃ１とポスト部１２ｃ２とが一体に形成された電気めっき膜である。【選択図】図１