Three-dimensional FEM simulations of thermomechanical stresses in 1.55 /spl mu/m laser modules

Deals with results achieved from nonlinear thermomechanical simulations using finite element method (FEM) of a direct modulation 1.55 /spl mu/m laser module for telecommunication applications. In this paper, two main parts will be developed: evaluation of stresses and strains in the critical zones based on both technological and thermomechanical analyses of the whole laser module (construction design, dissimilar materials, mismatched CTE) and relation between calculated strains and optical misalignment responsible for gradual power drift. Experimental failure analysis will be also conducted to validate thermomechanical simulations, focused in particular on laser weld joints. In this context, both thermal, electrical and thermomechanical simulations on the package must be realized using an original approach based on multiphysics computations of ANSYS software.