Shape and Force Relationships for Molten Axisymmetric Solder Connections

Abstract

The analysis for equilibrium shapes of axial symmetric solder connections is presented, which includes the consideration of surface tension, external, and gravitation forces. Four methods of calculating the shapes are explained. The analysis and calculation methods are applied to molten solder drops in contact with wettable circular pads, and to controlled collapse interconnections. A discussion of planar arrays of nonidentical solder connections, and the control of connector shape and height by the use of such nonuniformity is included.