Augmented Leadframe Design for Stable Multi-Wire Ground Bonding

Abstract

Technological change has brought the global market into broad industrialization and modernization. One major application in the semiconductor industry demands safety and high reliability with strict compliance requirement. This technical paper focuses on the package design solution of quad-flat no leads (QFN) to mitigate the leadframe bouncing and its consequent effect of lifted wire and/or non-stick on leads (NSOL) defects on multi-wire ground connection. Multi-wire on single lead ground (or simply Gnd) connection plays critical attribute in the test coverage risk assessment. Cases of missing wire and/or NSOL on the multi-wire Gnd connection cannot be detected at test resulting to Bin1 (good) instead of Bin5 (open) failure. To ease the failure modes mechanism, a new design of QFN leadframe package with lead-to-diepad bridge-type connection was conceptualized for device with extended leads and with multiple Gnd wires connection. The augmented design would provide better stability than the existing leadframe configurations during wirebonding. Ultimately, the design would help eliminate potential escapees at test of lifted Gnd wire not detected.

Research status and key technology analysis of integrated circuit lead frame

“…In the 1980s, China began to research and development and production of high strength and high conductivity copper calcium lead frame materials, but the lack of independent innovation awareness, only to introduce and copy, no in-depth systematic study of this kind of materials, resulting in a significant gap in technology and quality compared with foreign enterprises [3]. At present, the quality of high-strength and high-conductivity copper alloy materials developed and produced in China simply cannot meet the requirements of super-large integrated circuits, let alone meet the needs of the domestic market.…”