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The concepts of state variable modeling have been applied to obtain a general circuit like model for the power PIN diode. The main aim of this paper is to demonstrate the feasibility of the state variable modeling approach for the PIN diode. From simplified semiconductor device differential equations, the model is built with the corresponding variational equation using an internal approximation. With a special choice of the decomposition functional basis of such internal approximation, it was possible to get efficient and reliable models for the reverse recovery. A simple model of three state variables that has only six parameters, most of which are technological, represented a major improvement in describing circuit/device waveforms during reverse recovery.

A purely planar graphene/SiC field effect transistor is presented here. The horizontal current flow over one-dimensional tunneling barrier between planar graphene contact and coplanar two-dimensional SiC channel exhibits superior on/off ratio compared to conventional transistors employing vertical electron transport. Multilayer epitaxial graphene (MEG) grown on SiC(0001̅) was adopted as the transistor source and drain. The channel is formed by the accumulation layer at the interface of semi-insulating SiC and a surface silicate that forms after high vacuum high temperature annealing. Electronic bands between the graphene edge and SiC accumulation layer form a thin Schottky barrier, which is dominated by tunneling at low temperatures. A thermionic emission prevails over tunneling at high temperatures. We show that neglecting tunneling effectively causes the temperature dependence of the Schottky barrier height. The channel can support current densities up to 35 A/m.

Nano-composite films have been the subject of extensive work for developing the energy-storage efficiency of electrostatic capacitors. Factors such as polymer purity, nanoparticle size, and film morphology drastically affect the electrostatic efficiency of the dielectric material that forms the insulating film between the conductive electrodes of a capacitor. This in turn affects the energy storage performance of the capacitor. In the present work, we have studied the dielectric properties of four highly pure amorphous polymer films: polymethyl methacrylate (PMMA), polystyrene, polyimide and poly-4-vinylpyridine. Comparison between the dielectric properties of these polymers has revealed that the higher breakdown performance is a character of polyimide (PI) and PMMA. Also, our experimental data shows that adding colloidal silica to PMMA and PI leads to a net decrease in the dielectric properties compared to the pure polymer.

MOSFET-like CNTFETs suffer from band-to-band tunnelling, which in turn causes ambipolar conduction. A new structure based on the gate dielectric constant engineering is proposed. It is observed that the dielectric constant (k) plays an important role in modifying the energy band diagram. Therefore, by selecting suitable values of k over the source, channel and drain regions the tunnelling path at the source-channel interface could be eliminated. Consequently, the ambipolar conduction is suppressed.

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This paper presents a numerical study of quantization effects in gate-all-around nanowire transistors with circular cross section. The model is based on the self consistent solution of Schrödinger and Poisson equations. The eigenenergies and wavefunctions were first verified analytically whenever possible. Electron distribution profiles, body and surface potentials and capacitance characteristics are presented for specific examples.