| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem in a conventional circuit board that when resin is filled in a bump junction space between the component side and the surface of a board, the resin is not filled at an even permeation speed. <P>SOLUTION: A circuit board 11 has a solder resist 16 formed in shape of a window frame in a plan view on the board surface around lands 15. The solder resist 16 has an opening region 16a shaped like a rectangle in a plan view on the board surface including the lands 15, in which no solder resist material is applied. The solder resist 16 is set in such a way that a region D overlapping a board component side 13a of a chip component 12 has a length of 0 mm to 0.1 mm, both ends inclusive, in the direction toward the opening region 16a. This length is set equally on four sides around the opening region 16a, and the opening region 16a is approximately the same in size as the board component side 13a of the chip component 12. Therefore, the speeds at which resin permeates into a minute gap S and into a space K become almost equal, so that the resin is evenly filled in spaces beneath the chip component 12. <P>COPYRIGHT: (C)2013,JPO&INPIT |
