| 摘要 |
<p>PURPOSE:To form a board, for semiconductor mounting use, which can be made small-sized and thin and whose connection reliability is high by a method wherein a spherical protrusion used as a connection pad is formed in a signal- line extraction part on the rear of the board. CONSTITUTION:Opening parts on the rear side of through holes 2 used as signal- line extraction parts on a board 1 are coated with a conductive adhesive 6 such as a conductive silver paste or a solder paste. Then, spherical conductive particles 5 whose particle diameter is uniform are placed on the opening parts on the rear side of the through holes 2 on the board 1 by using a particle-feed sheet or the like where holes have been made in alignment with positions of the through holes 2; the conductive adhesive 6 is hardened or a solder is melted and then solidified; the particles are fixed; spherical protrusions 4 are formed. It is preferable to set a height of the spherical protrusions 4 to be nearly equal to the particle diameter of the conductive particles and at a range of 0.005 to 3mm.</p> |
