Creep damage study at powercycling of lead-free surface mount device
2009-04-30T13:07:56Z (GMT) by
Soldering is extensively used to assemble electronic components to printed circuit boards or chips to a substrate in microelectronic devices. These solder joints serve as mechanical, thermal and electrical interconnections, therefore, their integrity is a key reliability concern. However, newly introduced lead-free solders do not have a long history of applications in the industry and there is a lack of established material models of their behaviour over the wide temperature range experienced by electronics systems. Therefore, an extensive reliability study is required before introducing a new lead-free solder material in the electronic industries. Moreover, most of the solder materials have low melting temperatures, and are prone to creep in service. The cyclic temperature operating condition (powercycling) of the solder joint can result in the creep fatigue failure. Thus, a computational technique is used to investigate creep damage in solder joints. The present paper deals with creep damage of leadfree solder joints for powercycling using finite element analysis with the consideration of experimentally observed non-uniform temperature distributions in the 1206 surface mount chip resistor. In addition, a comparison is made for inelastic strain accumulation and fatigue life for creep damage study for spatially uniform and non-uniform temperature powercycling.