PRODUCTION OF MULTILAYER WIRING BOARD

摘要

PURPOSE:To enhance the positional accuracy of pattern on an inner layer plate by controlling water absorbing capacity of the inner layer plate at a specific level or below at the time of registration. CONSTITUTION:An inner layer plate is prepared (A). Etching resist is then laminated on the inner layer plate (B) and it is subsequently printed and developed (C). Etching is then carried out to form a circuit pattern and a registration guide mark simultaneously (D). A guide mark is then drilled through the inner layer plate (E). Water absorbing capacity of the inner layer plate provided with the guide hole is then lowered below 0.10% by drying. Electric drying furnace is preferably employed in the drying because shortening of the drying time is especially desirable. A plurality of inner layer sheets thus dried are then registered through adhesive sheets using guide pins (F). They ate then hot-pressed and laminated (G) thus producing a multilayer wiring board (H).