US 6,673,655 B2 · Method of making semiconductor device having improved heat radiation plate arrangement

Abstract

In a semiconductor device having a heat radiation plate, the tips of inner leads connected to a semiconductor chip have a lead width w and a lead thickness t, the width being less than the thickness. The inner leads are secured to the heat radiation plate. Fastening the inner leads to the heat radiation plate supports the latter and eliminates the need for suspending leads. A lead pitch p, the lead width w and lead thickness t of the inner lead tips connected to the semiconductor chip have the relations of w<t and p≦1.2t, with the inner leads secured to the heat radiation plate. The heat radiation plate has slits made therein to form radially shaped heat propagation paths between a semiconductor chip mounting area and the inner leads. In a molding member-sealed semiconductor device wherein the semiconductor chip is fixed to the heat radiation plate, the tip thickness t′ of the inner leads is made less than the thickness t of the other portions of the inner leads secured to the heat radiation plate.

Claims7

Dependent claims

A method of manufacturing a semiconductor device comprising steps of:

(a) preparing a lead frame having a framework and a plurality of leads inside said framework, wherein tips of said leads are divided from each other;
(b) preparing a heat radiation plate including a main surface and a back surface opposite to said main surface, said heat radiation plate having a first portion of said main surface, a second portion of said main surface that is at the outer periphery of said first portion and slits penetrating from said main surface to said back surface between said first portion and said second portion;
(c) preparing a semiconductor chip having a semiconductor element and a plurality of electrodes formed on a principal plane;
(d) fastening said semiconductor chip on said first portion of said heat radiation plate;
(e) fixing said tips of leads on said second portion of said heat radiation plate;
(f) after the step (e), bonding wires on said tips of said leads and electrically connecting said leads to said electrodes of said semiconductor chip;
and
(g) after the step (f) sealing said tips of said leads, said heat radiation plates said semiconductor chip and said bonding wires with a molding member.

5 more elements

Dependencies are inferred from the claim text.

Method of making semiconductor device having improved heat radiation plate arrangement

Life of this patent

Method of making semiconductor device having improved heat radiation plate arrangement

Life of this patent

Abstract

Claims7