Method for manufacturing a plastic encapsulated semiconductor device and a lead frame therefor

Abstract

Abstract A method for manufacturing a plastic encapsulated semiconductor device is provided which comprises the steps of: clamping by upper and lower molds at least external leads and strips of a semiconductor device assembly formed using a lead frame which has a first connecting band connected to the external leads extending from one side of a substrate support further used as a heat sink, and a second connecting band connected to the strips having portions of small cross-sectional areas and of a predetermined length and extending from the other side of the substrate support, the cross sections being perpendicular to an extending direction of the strips, so that the substrate support may float in a cavity formed by the upper and lower molds and parts of the portions of small cross-sectional areas may be disposed in the cavity and the remaining parts thereof may be disposed between the upper and lower molds; injecting a plastic into the cavity; and cutting the portions of small cross-sectional areas of the strips which extend outside a plastic encapsulating housing along the end face of the plastic encapsulating housing and cutting a connecting portion between the external leads and the first connecting band. Also provided is a lead frame having the strips as decribed above. A plastic layer of desired thickness can be formed on the rear surface of the substrate support. Cutting of the strips from the plastic encapsulating housing is easy and reliable.

Inventors

• 👤 Kenichi Tateno
• 👤 Masami Yokozawa
• 👤 Hiroyuki Fujii
• 👤 Mikio Nishikawa
• 👤 Michio Katoh
• 👤 Fujio Wada

Bibliographic Details