الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
In the past few years, a new transistor has appeared on the scene, made of GaAs and AlGaAs, which now holds the record as the fastest logic switching device [1], switching at speeds of close to ten trillionths of a second (10 ps) [2]. The device evolved from the work on GaAs-AlGaAs superlattices pioneered by Esaki and Tsui at IBM in the late 1960’s [3]. Dingle et al., [4] were the first to demonstrate high mobilities obtained by modulation doping in a GaAs-AlGaAs superlattice. In 1980, the first such device with a reasonable microwave performance was fabricated by the University of Illinois and Rockwell [5], which they called a Modulation-Doped FET or MODFET. The same year Fujitsu reported the results obtained in a device with a 400-?m gate which they called the “High Electron Mobility Transistor” or HEMT, in the open literature [6]. Since then, the HEMT has been the focus of research on high-speed and high-frequency semiconductor devices. In order to fabricate large scale integrated (LSI) circuits using HEMT’s it is necessary to develop simple yet accurate device models for use in circuit simulation. This has prompted the development of various simulation analytical models to obtain the current-voltage (I-V) characteristics of HEMT’s. In the present work, we present a current-voltage and capacitance-voltage HEMT model, which uses a polynomial carrier concentration-gate voltage variation, does not use any fitting parameters, does not resort to iteration at any stage. The model takes into account the contribution from parasitic MESFET, which causes transconductance compression at high gate voltages. The model is able to cover the whole operation range of the HEMT including the subthreshold region. In order to check the validity of the model, it is applied to eight different devices and the results show excellent match with experimental data.