Comparison of Electrical, Thermal, and Mechanical Performances of a fcBGA with that of a Fan-Out SiPlet Package

This paper studied a package originally designed with a flip chip ball grid array package (fcBGA), and now is converted to a single-chiplet fan-out package (SiPlet™). The simulation or experimental data is used to compare the electrical, thermal, and mechanical performances of a fcBGA and a SiPlet™. The SiPlet™'s redistribution layers (RDL) are much thinner compared to the substrate layers on the fcBGA package. The thin RDL layers of SiPlet™ mean smaller distances in between the signal traces and the ground planes, and, as a result, the package has lower crosstalk. The thinner RDL layers on the SiPlet™ package also help reduce the transmission loss of electrical signals. The impedance, Insertion Loss (IL), Return Loss (RL), and far-end crosstalk of both fcBGA and SiPlet™ were simulated and compared. From the thermal aspect, the thermal conductivities of the dielectric layers are usually very low, such that the thin RDL of SiPlet™ introduces very low thermal resistance for the heat to be dissipated from silicon to the bottom components. [1] Finally, the mechanical behaviors and the cost of manufacturing are discussed to have a more thorough picture of the differences of two packages. [2]