Christopher M. Snowden

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In this paper, we present a multiphysics 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 physics-based multicell electrothermal equivalent circuit model is described that is applied to the large-signal microwave characterization of AlGaAs/GaAs HBT’s. This highly efficient model, which incorporates a new multifinger electrothermal model, has been used to perform dc, small-signal and loadpull characterization, and investigate parameter-spreads(More)
The need for both linear and efficient pHEMTs for modern wireless handsets necessitates a thorough understanding of the origins of intermodulation distortion at the device level. For the first time, two-tone time domain simulations of a microwave pHEMT using a quasitwo-dimensional physical device model in a CAD environment are presented. The model fully(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)
A comprehensive modeling approach is applied to the study of pHEMT transistors for microwave power amplifier applications. This approach combines physical, electromagnetic and thermal simulations to model large power transistors used in these applications, allowing both the individual finger contribution and the global performance to be investigated in an(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)
The standard methods used for analysing the reliability of electronic systems are unsuited to VLSI systems because of their large-scale and software-driven nature. In this paper, a review of the problems is presented together with an analysis of the difficulties encountered in extrapolation of the present techniques. Some proposals are presented with the(More)
Two problems in the self-consistent, electrothermal co-simulation of nanoscale devices, are discussed. It is shown that the construction of dynamic compact thermal models for nanoscale devices, based on solution of the hyperbolic (wavelike) heat transport equation, can follow essentially the same approach as the authors’ analytical thermal impedance matrix(More)
The coupling between charge transport, heat and energy flow required to model high frequency power devices is developed in the context of a computationally efficient physicsbased model, which has been successfully applied to microwave laterally diffused MOS transistors. The accurate prediction of smalland large-signal microwave characteristics, and the(More)