Application of TAB outer lead bonding technique for high lead count flat package IC assembly

A technique for bonding outer leads for a TAB (tape automated bonding) part onto inner leads for a metal lead frame has been employed to achieve high-lead-count and high-lead-density FPIC (flat package integrated circuit) assembly. An automated bonding machine that bonds all the outer leads simultaneously with high alignment accuracy has been developed. Tin-plated (35- mu m-thick) copper TAB leads were connected to gold-plated nickel-alloy lead frames (0.15-mm thick) under 100 degrees C preheat, 400 gf/lead bonding compression, and 450 degrees C bonding heat for 1 s. Alignment accuracy +or-36 mu m was realized using 380000-pixel CCD cameras and original gray-scale image processing software. The authors present experimental results regarding the reliability of a quad flat package with 184-lead TAB.<>