Patent 8007629 was granted and assigned to Panasonic on August, 2011 by the United States Patent and Trademark Office.
A method of manufacturing a multi-layer circuit board including preparing a laminated member formed of (i) a core circuit board having a circuit pattern thereon and (ii) a prepreg sheet having a through-hole filled with conductive paste, forming a laminated structure such that the laminated member is sandwiched by lamination plates, and applying heat and pressure to the laminated structure. According to this method, selecting a lamination plate that has a thermal expansion coefficient that is equivalent to that of a core circuit board will protect the conductive paste from distortion, thereby offering a high-quality multi-layer circuit board having a reliable connection resistance.