Electro-thermal Modelling of Monolithic and Hybrid Microwave and Millimeter Wave IC's

The first completely physical electro-thermal model is presented that is capable ofdescribing the large signal performance of MESFET- and HEMT-based, high powermicrowave and millimeter wave monolithic and hybrid ICs, on timescales suitable forCAD. The model includes the effects of self-heating and mutual thermal interactionon active device performance with full treatment of all thermal non linearities. Theelectrical description is provided by the rapid quasi-2D Leeds Physical Model and thesteady-state global thermal description is provided by a highly accurate and computationallyinexpensive analytical thermal resistance matrix approach. The order ofthe global thermal resistance matrix describing 3-dimensional heat flow in complexsystems, is shown to be determined purely by the number of active device elements, notthe level of internal device structure. Thermal updates in the necessarily iterative, fullycoupled electro-thermal solution, therefore reduce to small matrix multiplicationsimplying orders of magnitude speed-up compared to the use of full numerical thermalsolutions capable of comparable levels of detail and accuracy