Christopher M. Snowden

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—An original, fully analytical, spectral domain decomposition approach is presented for the time-dependent thermal modeling of complex non linear three-dimensional (3-D) electronic systems, from metallized power FETs and MMICs, through MCMs, up to circuit board level. This solution method offers a powerful alternative to conventional numerical thermal(More)
—The history of RF and microwave computer-aided engineering is documented in the annals of the IEEE Microwave Theory and Techniques Society. The era began with elaborate analytically based models of microwave components and simple computer-aided techniques to cascade, cascode, and otherwise connect linear component models to obtain the responses of linear(More)
—A unique electromagnetic (EM)–electrothermal global simulation tool based on a universal error concept is presented. The advantages of this electrothermal model are illustrated by comparison with a commercial electrothermal circuit simulator. The first description of a fully physical, electrothermal, microwave circuit simulation, based on coupling of the(More)
A physics-based multi-cell electro-thermal equivalent circuit model is described which is applied to the large-signal microwave characterization of AlGaAs/GaAs HBTs. This highly efficient model, which incorporates a new multi-finger electro-thermal model, has been used to perform DC, small-signal and load-pull characterization and investigate(More)
—In this paper, we present a multi-physics approach for the simulation of high-power microwave transistors in which electromagnetic, thermal, and nonlinear transistor models are linked together within a harmonic-balance circuit simulator. This approach is used to analyze an LDMOS transistor operating at 2.14 GHz. The total gate width of the die is 102 mm,(More)
This paper addresses the state-of-the-art in microwave and millimetre-wave power transistor technology. The relative performance of microwave power transistor technology from 1 GHz to 60 GHz is reviewed. The fundamental technological drivers in the design of microwave compound semiconductor power transistors are discussed as the basis for developing optimum(More)
Our aim is to foster close working and understanding between business and higher education so that world-class learning and research can improve the international competitiveness of both sectors and the capabilities of graduates and those already in the workforce. The Council leads in developing an agreed agenda on the higher level learning issues that(More)
—In this paper, we present a multi-physics approach for the simulation of high-power RF and microwave transistors, in which electromagnetic, thermal, and nonlinear transistor models are linked together within a harmonic-balance circuit simulator. This approach is used to analyze a laterally diffused metal-oxide semiconductor (LDMOS) transistor that has a(More)
— A new quasi-two-dimensional (Q2D) model is described for microwave laterally diffused MOS (LDMOS) power transistors. A set of one-dimensional energy transport equations are solved across a two-dimensional cross-section in a "current-driven" form. This process-oriented nonlinear model accounts for thermal effects, avalanche breakdown and gate conduction.(More)