The availability of the thermal resistance model in flip-chip packages

Thermal resistance model is very simple and good tool for thermal analysis of package system. In this study, thermal resistance model was compared with simulation tool and real measurement values of flip-chip package which was made by using DTSA (Diode Temperature Sensor Array). Especially, a micro thermocouple sensor array - DTSA - has been developed to investigate the temperature distributions of underfill in flip-chip package. Various fillers were used with underfill resin system, silica, diamond, and alumina. The temperature distribution of flip- chip package was changed with various underfill system. ICEPAK simulation tool predicted the change of temperature distribution of package well and using same physical dimension, we made a thermal resistance model circuit and calculated thermal resistance values with various underfill system's thermal conductivity values which were measured with the laser flash method. Finally, measured values with DTSA was compared with ICEPAK simulated values and thermal resistance model. All three different method's thermal resistance values of maximum temperature were lay 20degC/W ~ 25degC/W. Thermal resistance model predicted the thermal resistance of DTSA flip-chip package well.