Determination of Thermal Induced Stresses in Semiconductor Chip Package by using Finite Element Analysis: A Brief Review Shantanu. P Patil Department of Mechanical Engineering Sinhgad Institute of Technology and Science Pune, India Govind Waghmare Department of Mechanical Engineering Sinhgad Institute of Technology and Science Pune, India Abstract— In todays advanced electrical technology, it becomes necessity to use compact semiconductor chips in variety of areas like computers, electrical appliances, automotive etc., clearly the need of more and more sophisticated packages is increasing. As the need of faster computer increases design of denser and more complicated packages becomes unavoidable, more complicated packages means that, the size of chip more or less remains same, but it has more electronic circuitry per unit surface area, this, of course increases the temperature of packages and causes thermal expansion due to change in coefficient of thermal expansion of the constituent materials. Thermal stresses ultimately cause the failure of the device. An IC package mainly consist of four parts, silicon die (chip), polymeric substrate, plastic molding compound and connectivity parts, lead frames and bond wires. The silicon chip is assembled on a polymeric substrate, plastic molding compound surrounding both parts, lead frames and bond wires provide electrical connectivity between the package and board on which assembly is made. The complicated geometrical structure and different material properties as well as the loading conditions made it almost impossible to study the mechanical behavior of semiconductor package analytically; therefore the finite element method has become a useful tool for evaluation of problems encountered in this area. Keywords— Semiconductor Chips, Thermal Analysis, FE Analysis, Temperature Of Package I. INTRODUCTION The objective of the review is to carry out a number of finite element (FE) analyses to predict thermal and mechanical stresses in the semiconductor package and optimize its shape. The interfacial integrity of an integrated circuit (IC) is a very significant reliability issue for service life performances. Any sort of interface degradation can cause failure of chip or if not, affects its efficiency resulting in substandard operations.in addition to delamination failure modes. Other structural failure includes, metal line deformation, passive cracking, dielectric cracking, wire bond shear and epoxy molding compound cracking. The thermal stresses in semiconductor packages are caused by thermal expansion (contraction), mismatch of dissimilar materials and/or non-uniform temperature distribution within the package and may result in failure of the package. The normal stresses in a bi-material assembly are an important aspect in studying the thermal stresses induced in the semiconductor die substrate assembly. Multicolored, multilayered structures are needed for IC’s, MCM and PCB system, due to important effect on the transmission of high speed signals. Also the transmission lines effects on the IC interconnects becomes extremely important for the transmission behavior of interconnects lines on silicon oxide-silicon semiconducting substrate. The conducting silicon substrate causes capacitive and inductive coupling effect in the structure. For advanced IC’s, the packaging technology mainly based on the area- array packages or the flip-chip solder interconnects. This type of package connects the active device side of the silicon die face via solder balls on a multilayered wiring substrate .A new design of Flip-Chip Ball grid array (FCBGA) package is shown in the Fig.1 shows the detailed construction of FCBGA. Fig. 1. Flip-Chip ball grade array construction II. INTRODUCTION TO FINITE ELEMENT METHOD The Finite element method (FEM) has devloped in to a key, indispnsable technology in the modelling and simulation of advanced engineering syatems in various fields like transportation, communication and building and so on [1]. This techinque has been applied over many years to solve problem of thermal analysis, structural analysis, fluid mechanics analysis ,electromagnetic analysis and many others. This strong and promising technique plays an important role in manufacturing processes of advanced engineering systems. Modelling and simulation of engineering system based on finite element method are two sophisticated processes which engineer go through the fabrication of final product. At the moment a large number of simulation software packages like Abaqus, Ansys, Adina, COMSOL etc. that implement finite element method are available. Engineers across the world use these simulation software packages to provide solution for many complicate design egineering problems that would otherwise be extremely difficult to obtain. The FEM is a numerical method seeking an approximate solution of distribution of field variables like the dispaclement in stress analysis or the International Journal of Engineering Research & Technology (IJERT) ISSN: 2278-0181 www.ijert.org IJERTV4IS040112 (This work is licensed under a Creative Commons Attribution 4.0 International License.) Vol. 4 Issue 04, April-2015 44