Title :
The thermal-cycled adhesion of thick-film copper conductors
Author :
Needes, Christopher R S ; Knaak, Joachim F.
Author_Institution :
Du Pont Co., Wilmington, DE, USA
Abstract :
The thermal-cycled adhesion performance of a high-solder-acceptance, high-adhesion, mixed-bonded copper conductor is described. An empirical expression that relates the adhesion strength of the conductor to the number of thermal cycles and to their temperature extremes has been developed. Refinements to the expression include the shape and duration of the thermal cycles and the influence of conductor thickness. The qualitative effects of solder type and the presence of underlying dielectric are also discussed. The performance of the conductor is compared to that for two other thick-film copper conductors; one is a mixed-bonded, low-firing temperature material (600 degrees C), and the other is an earlier generation material used as the experimental control. Significant chemical and metallurgical changes occur during the thermal cycling of a solder joint. Observations from the present work have been used to develop a general picture of the joint-weakening processes.<>
Keywords :
adhesion; copper; hybrid integrated circuits; integrated circuit technology; microassembling; thick films; 600 C; Cu-Al/sub 2/O/sub 3/; adhesion strength; conductor thickness; empirical expression; hybrid microcircuit design; joint-weakening processes; solder joint; thermal-cycled adhesion; thick film conductor; Adhesives; Chemicals; Conducting materials; Conductors; Copper; Dielectric materials; Shape; Temperature control; Thermal conductivity; Thickness control;
Conference_Titel :
Electronics Components Conference, 1988., Proceedings of the 38th
Conference_Location :
Los Angeles, CA, USA
DOI :
10.1109/ECC.1988.12658
