ELECTRONIC PART WITH IMPROVED THROUGH HOLE TO REDUCE SIZE OF PRODUCT AND IMPROVE CONNECTION RELIABILITY OF CONDUCTOR

摘要

PURPOSE: An electronic part is provided to reduce the size of a product and improve the connection reliability of a conductor by improving the structure of a through hole. CONSTITUTION: A through hole(40) is formed in a substrate(10). A conductor(31) for connecting electrically one side of the substrate with the other side of the substrate is filled in the through hole. The through hole includes a major axis diameter(D3) at one side of the substrate and a minor axis diameter(D4) at the other side of the substrate. The through hole is satisfied with l<(D3/D4) <=5.