Circuit board and method of manufacturing the same

摘要

Through holes (104) formed in an electrical insulating substrate (102) having adhesive layers (101) on its both surfaces are filled with a conductor (105). Then, supporting bases (106) having wiring layers (107) with a predetermined pattern are laminated on both the surfaces of the electrical insulating substrate (102), which are then heated and pressurized. After that, the supporting bases (106) are removed, thus obtaining a circuit board in which the wiring layers (107) have been embedded in the adhesive layers (101). The conductor (105) within the through holes (104) are compressed sufficiently, thus forming minute via holes with high reliability. <IMAGE>