Finite element analysis of substrate warpage during die attach process

A parametric study of the impact of design parameters and material properties on high density interconnect (HDI) or substrate warpage during the die attach process is presented in this article. Finite element analysis (FEA) was used to study the sensitivity of substrate warpage to changes in the substrate material properties and to variations in design parameters. A total of six parameters have been investigated including material properties (coefficient of thermal expansion, and Young's Modulus), copper volume, copper distribution, plated through hole (PTH) number, PTH array and substrate thickness. The results obtained provide a better understanding on how the design parameters and material properties affect the substrate warpage. The shadow Moire technique was used to measure the thermally induced warpage of the substrate for model validation.