| 摘要 |
PURPOSE:To coat an external connecting lead excellently with solder by forming a recessed section opened in the width direction to both side edges of the external connecting lead, the surface thereof is coated with solder. CONSTITUTION:The depth of notch of a recessed section 11 is inhibited to one fifth or less of lead width in consideration of the flexural strength of a lead material, and molten solder is introduced into the recessed section on solder coating. When a semiconductor device, external connecting leads 2, 3 and 4 therein are positioned in a tub 7, is pulled up, solder coating films 8 in nose sections are not thickened as compared to sections in the vicinity of a molding section 5 as seen in conventional devices because solder under the state of semi- solidifying flowing in the direction of the noses of the external connecting leads is introduced into the recessed sections 11, and the solder coating films 8 in approximately the same thickness are formed on the surfaces of the external connecting leads 2, 3 and 4. |
