An electroplating method that is a conventional method has had a problem that it is difficult to manufacture fine pillars without being affected by an undercut. Furthermore, an electroless plating method has had a problem that it is difficult to manufacture pillars having the same shape without any void. The inventors have performed intensive investigations to solve the above problems and, as a result, have found that fine conductive pillars with a high aspect ratio can be readily manufactured on a substrate having an electrode section in such a manner that after a conductive paste containing metal micro-particles is applied in a reduced pressure state, the conductive paste is exposed to standard pressure. The present invention has a particular effect on the manufacture of a metal pillar that is a terminal for flip-chip mounting.

The known electrolytic plating method is disadvantageous in that it is difficult to form thin pillars without being influenced by undercuts. The electroless plating method is disadvantageous in that it is difficult to form pillars in the same shape without voids. As a solution to these, the electrically conductive paste according to the present invention for forming pillars is used to make pillars by filling. This helps prevent undercuts, and it is also intended to provide metal pillars in the same shape with good reproducibility. The inventors found that an electrically conductive paste that is very small fine metal particles and contains a particular percentage of fine metal particles is extraordinarily advantageous in forming pillars.