| 摘要 |
PURPOSE:To reduce the absolute value of the dimension changing rate of the title laminated board so as to reduce the dimensional fluctuation by forming the laminated board by using copper foil having a high percentage of extension, on which annealing and circuit working are performed, and a glass-cloth substrate which is specified in the difference between longitudinal and transversal launching strand numbers. CONSTITUTION:An internal-layer circuit board is produced by performing annealing and circuit-working on a copper-plated laminated layer board for internal-layer circuit obtained by using copper foil having a high percentage of extension of 13-25% at 25 deg.C, with the annealing process being performed for 2-5 hours at a temperature higher than the glass transition temperature (Tg) of the resin used for forming the laminated board, but lower than (Tg+50 deg.C). This laminated board is formed by performing forming under heat and pressure on a laminated body of such internal-layer circuit board and prepreg formed principally of glass-cloth having a nominal thickness of 0.05mm, total lunched number of 102-110 pieces/square inch, and difference of 17-23 pieces in launched number between the longitudinal and transversal directions. Therefore, the dimensional change of the laminated board during the processing process and dimensional anisotropy between the longitudinal and transversal are reduced. In addition, the accuracy and density can be improved. |
