| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a printed wiring board which is ultrathin, hardly warped, high in thermal resistance, kept high in electrical insulation properties after it absorbs moisture, and superior in electromigration resistance. SOLUTION: A circuit board is formed using a glass cloth base double-sided copper-plated laminate board of thickness 0.04 to 0.15 mm as substrate of a semiconductor plastic package, a prepreg of a glass cloth base thermosetting resin composition e of the same thickness is laminated on each side of the circuit board. Bonding pads f and ball pads g are removed through a sand blast method, and the circuit board is plated with precious metal to serve as a printed wiring board. Furthermore, polyfunctional cyanate resin composition is used as the resin for the copper-plated laminated board and the prepreg.</p> |
