Patent ID: 7484190

Claim:
A method of computing quality metrics of an assembly, the assembly including a packaged integrated circuit (IC), a substrate, and a plurality of interconnects joining the IC and the substrate, each interconnect being characterized by a plurality of parameters, the method comprising: (a) pre-calculating restoring forces for each interconnect in a fluidic state as a function of the plurality of parameters; (b) generating an initial set of parameters for each interconnect from predetermined joint probability distributions; (c) generating an initial position of the IC; (d) computing restoring forces for each interconnect by interpolating pre-calculated restoring forces based on the position of the IC and on the set of parameters; (e) computing net forces and moments on the IC based on the restoring forces; (f) testing whether convergence has been reached by comparing the absolute value of each of the net forces and moments with a corresponding predetermined tolerance; (g) if convergence has not been reached, updating the position of the IC based on the net forces and moments, and repeating steps (d) through (g); and (h) computing quality metrics based on the position of the IC and the parameters of the plurality of interconnects.