This paper addresses Qorvo’s integrated approach to thermal design that leverages modeling, empirical measurements (including micro-Raman thermography), and finite element analysis (FEA) for high performance microwave GaN HEMT devices and MMICs. This methodology is highly effective and has been empirically validated. By properly addressing FEA boundary condition assumptions and the limitations of infrared microscopy, resulting model calculations are more accurate at both the product and end application level than traditional methods based on lower power density technology.