Semiconductor device

Abstract

Abstract PURPOSE:To make the junction between an inner lead and an electrode highly reliable by a method wherein a metallic bump is fixed to one end of inner lead while small protrusions are formed on the junction of metallic bump. CONSTITUTION:A metallic bump 13 formed on a quadrangular cone provided with small protrusions 14 on the junction 19 is fixed on the edge lower surface of an inner leads 15 through the intermediary of a plated layer 16 by thermal pressure fixing process, etc. An aluminium electrode 18 is formed on a proper surface of a semiconductor element 17 while the peripheral part thereof is coated with a passivation film 20. In order to junction one end of inner lead 15 to the electrode 18, the metallic bump 13 is molten-formed into one body of the electrode 18 by providing the metallic bump 13 with thrust and heat using a pressurizing tool. Through these procedures, the thrust of pressurizing tool can be concentrated on the small protrusions 14 so that the surface oxide film of electrode 18 on the semiconductor element 17 may be easily broken to increase the junction strength making the junction highly reliable.

Inventors

• 👤 Yoshifumi Kitayama
• 👤 北山　喜文
• 👤 Yukio Maeda
• 👤 幸男 前田

Bibliographic Details