Title :
Design of 0.35-mm pitch QFP lead and its assembly technology
Author :
Totani, Makoto ; Teshima, Yasuhiro ; Ito, Nobutaka ; Nagatake, Mami ; Otaguro, Hiroyuki
Author_Institution :
Micro-Component & Module Technol. Dept., Fujitsu Labs. Ltd., Kawasaki, Japan
fDate :
8/1/1995 12:00:00 AM
Abstract :
The solder joint reliability of a 0.35-mm lead pitch, 42-mm wide×42-mm long×23-mm high, 396 pin, ceramic quad flat package (QFP) was studied in terms of: 1) finite element analysis simulation; and 2) temperature cycling tests between -65°C and +125°C. Using the study results, physical design of the QFP leads, in terms of thickness, standoff, and Au surface finish were optimized. If the von Mises stress of a QFP solder joint can be optimized to be no more 16.7 kilogram square millimeter, we can guarantee QFP solder joint reliability over requested design life. Also, we developed a thermocompression (T/C) soldering process for the QFP
Keywords :
fine-pitch technology; finite element analysis; integrated circuit packaging; integrated circuit reliability; lead bonding; soldering; surface mount technology; -65 to 125 C; 0.35 mm; Au; Au surface finish; FEM; QFP lead design; assembly technology; ceramic quad flat package; finite element analysis simulation; solder joint reliability; temperature cycling tests; thermocompression soldering process; von Mises stress optimisation; Analytical models; Assembly; Ceramics; Design optimization; Electronics packaging; Finite element methods; Lead; Soldering; Temperature; Testing;
Journal_Title :
Components, Packaging, and Manufacturing Technology, Part B: Advanced Packaging, IEEE Transactions on
