Thermal characterization of MMIC by numerical analysis

Thermal resistances (R_th) of monolithic microwave integrated circuits (MMIC) for the Ka-band communications satellite´s transponder, which is being developed by ETRI, have been calculated by the finite element method (FEM). Through the analyses of finite element models with or without selective metal layers, additional MMIC´s thermal characteristics have been found and a reasonably simplified finite element modeling method for MMIC has been introduced. Parametric studies on the relations between the total gate width or the power dissipation and the thermal resistance were performed. With the parametric study results, an equation for calculating the thermal resistance of an MMIC showing error of 6% or less has been developed.