MANUFACTURING METHOD OF PRINTED WIRING BOARD

• Main Author: MIZUTANI YOSHIO
• Format: Patent
• Language: English; Japanese
• Published: 24.10.2023
• Subjects: CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS; PRINTED CIRCUITS

To provide a manufacturing method of a printed wiring board that can form a uniform plating layer thickness when the through-hole arrangement density is uneven.SOLUTION: A manufacturing method of a printed wiring board includes forming a through hole 4 in a copper clad laminate 3 having a core substrate 1 and a copper foil 2 on the surface of the core substrate, forming a high-density region 5 and a low-density region 6 having different densities of through holes in a copper clad laminate, forming a plating layer 7 in the through hole and in high-density regions and low-density regions on the copper foil, performing blackening treatment on the plating layer, and irradiating only the low-density regions of the plating layer with the CO2 laser to reduce the thickness of the plating layer in the low-density regions. The thickness of the plating layer 7 in the high-density region 5 and the low-density region 6 is made uniform.SELECTED DRAWING: Figure 1E 【課題】スルーホール配置密度に偏りがある場合、めっき層の厚さを均一に形成することができるプリント配線板の製造方法を提案する。【解決手段】コア基板１とコア基板の表面の銅箔２とを有する銅張積層板３にスルーホール４を形成し、銅張積層板にスルーホールの存在密度の異なる高密度領域５と低密度領域６とを形成することと、スルーホール内および銅箔上の高密度領域と低密度領域にめっき層７を形成することと、めっき層に黒化処理を行うことと、めっき層の低密度領域のみにＣＯ２レーザを照射し、低密度領域のめっき層の厚さを薄くすることと、を含み、高密度領域５および低密度領域６のめっき層７の厚みを均一にする。【選択図】図１Ｅ