| 摘要 |
PURPOSE:To obtain a viahole forming method of a thin film multilayered board by using a sputtering method. CONSTITUTION:In a first process, photosensitive resin is spread on a board 1 on which a lower wiring 2 is formed, and a photosensitive resin layer 3 is formed by baking. In a second process, exposure light is defocused at the time of photolithography process of a viahole 7 set part, defocusing amount is controlled, the light amount casted on the shoulder part of an photosensitive resin hole 5 is smoothly attenuated to zero toward the outside from the inside, exposure.development is performed, the unnecessary part of the photosensitive resin layer 3 is eliminated, the lower wiring 2 is exposed, and the photosensitive resin hole 5 wherein the peripheral shoulder part is smooth is formed. in a third process, a metal layer 6 for upper wiring is formed, and a viahole 7 is formed in the photosensitive resin hole 5 wherein peripheral shoulder part is smooth, thereby electrically connecting the metal layer 6 for upper wiring with the lower wiring 2. |
