Title :
Finite element analysis of compliant coating
Author :
Shoraka, F. ; Gealer, C. ; Bettez, E.
Author_Institution :
Intel Corp., Chandler, AZ, USA
Abstract :
Finite-element analysis (FEA) was used to explore the effect of key materials and process parameters relating to die-coat chemistry and thickness on the die surface and internal-package stress. Lower stresses are achieved with silicone gel compared to silicone RTV, modified polyimide, and polyimide coatings, as predicted by internal-stress calculations based on the integral of Young´s modulus and thermal coefficient of expansion (TCE). The stress reduction mechanism is related to the decoupling of the die-surface/molding-compound interface. It is verified that thin-film cracking can be eliminated by using a thin film of silicone gel as shown by improved thermal cycle performance of a 68-lead plastic-leaded chip-carrier (PLCC) package.<>
Keywords :
encapsulation; finite element analysis; gels; internal stresses; packaging; plastics; silicones; stress analysis; PLCC; Young´s modulus integral; die-coat chemistry; die-surface/molding-compound interface; encapsulation; finite element analysis; internal-package stress; internal-stress calculations; plastic leaded chip carrier package; polyimide coatings; silicone RTV; silicone gel; stress reduction mechanism; surface mount technology; thermal coefficient of expansion; thermal cycle; thin-film cracking; Chemistry; Coatings; Finite element methods; Internal stresses; Plastic films; Plastic packaging; Polyimides; Semiconductor thin films; Thermal expansion; Thermal stresses;
Conference_Titel :
Electronics Components Conference, 1988., Proceedings of the 38th
Conference_Location :
Los Angeles, CA, USA
DOI :
10.1109/ECC.1988.12633
