| 摘要 |
PURPOSE: To reduce stress concentration at the time of packaging a semiconductor device, and make the stress hard to be a start point of crack, by polishing and beveling an edge part worked along outline, by using electropolishing. CONSTITUTION: A lead frame 10 is a single layer lead frame for a QFP semiconductor device, composed of 42 alloy, and subjected to outline working by etching. The semiconductor element mounting sides of a die pad 11 and an inner lead 12 tip are plated with silver 17. After the outline working by etching, the whole part of the lead frame is polished by 0.3μm by electroplating, and the edge part is beveled to form a beveling part 18. Electrodeposition resist is formed on the whole surface of the lead frame and engraved in a specified form. Only the part where plating is necessary is plated with silver. In this case, the electrodeposition resist is not thinned in the beveling part 18, and abnormal deposition of silver is not generated. |
