| 摘要 |
PURPOSE:To downsize a board while preventing trouble, e.g. defective connection, at interlayer connecting part when a large number of miniature electronic components are mounted on a multilayer board. CONSTITUTION:In a multilayer board having more than two conductor layers and miniature electronic components are mounted in internally provided holes, interlayer connection is carried out by means of solders 62, 90 having different melting points from high temperature to low temperature according to the production steps. |
