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1 – 5 of 5I.C. KIZILYALLI, K. HESS, G.J. IAFRATE and D. SMITH
The dynamical characteristics of electron transfer between two channels are elucidated by using a many‐particle Monte Carlo model with self‐consistent electric fields. The study…
Abstract
The dynamical characteristics of electron transfer between two channels are elucidated by using a many‐particle Monte Carlo model with self‐consistent electric fields. The study has been performed to assess switching speeds associated with various novel devices such as velocity modulation transistors and dual channel high electron mobility transistors. Typical time constants for a one micrometer device (0.4 µm gate length) are 3.5 psec for the longitudinal (source‐to‐drain) and 0.2 psec for the transport perpendicular to the interfaces between the two channels.
A two‐dimensional numerical computer simulation based on the analysis of the first three moments of the Boltzmann equation, known as the energy‐transport model, has been used to…
Abstract
A two‐dimensional numerical computer simulation based on the analysis of the first three moments of the Boltzmann equation, known as the energy‐transport model, has been used to study various two‐dimensional effects on the performance of AlGaAs/GaAs heterostructure field‐effect transistor. The results are presented for half‐micron gate length. The calculation reveals significant electron current contribution coming from the AlGaAs region between the source and gate, contributing to the reduction of access resistance. As the electrons acquire large energies near the drain side edge of the gate, real‐space transfer to the AlGaAs region from the “two‐dimensional” electron gas channel occurs. However, at the drain end, the electron current is confined at the GaAs side of the heterointerface. The result shows insignificant current contribution from regions of depth greater than 0.048 µm into the undoped GaAs bulk. At room temperature, the results indicate transconductance, current gain cutoff frequency and power density about twice that which are calculated for “equivalent” GaAs MESFET, of identical structure and doping level as the heavily‐doped AlGaAs region. These results suggest that HEMT devices have the potential for providing significant sources of power at millimeter‐wave frequencies.
C. Moglestue, F. Buot and W.T. Anderson
The response of a MESFET and an inverted HEMT to the impact of an a particle has been calculated by means of the Monte Carlo Particle Model, a technique for solving Boltzmann's…
Abstract
The response of a MESFET and an inverted HEMT to the impact of an a particle has been calculated by means of the Monte Carlo Particle Model, a technique for solving Boltzmann's transport and Poisson's field equation self‐consistently in space and time. The calculations show that all the terminals of the MESFET react by generating an initial current pulse followed by another; the timing of the second pulse depends on the angle of incidence of the α particle. The lattice heating rate was found to be largest at the corners of the Ohmic contacts. The HEMT, on the other hand, hardly reacts electrically to the α particle but is more likely to burn out in an a particle radiation environment because of the larger lattice heat generation taking place in the interior of the transistor. The results also support the theory of the hot‐electron induced subsurface catastrophic failure mechanism.
Oscar Lucia, Hector Sarnago and José M. Burdio
Wide-bandgap (WBG) semiconductors have emerged as a disruptive technology in the power electronics sphere. This paper aims to analyse and discuss the importance for induction…
Abstract
Purpose
Wide-bandgap (WBG) semiconductors have emerged as a disruptive technology in the power electronics sphere. This paper aims to analyse and discuss the importance for induction heating systems and gives some examples and highlights some future design trends and perspectives.
Design/methodology/approach
The benefits of WBG semiconductors are reviewed with a special emphasis on induction heating applications.
Findings
WBG devices enable the design of higher-performance induction heating power supplies. A significant selection of the reported converters is discussed, highlighting the benefits of this technology.
Originality/value
This paper highlights the benefits of WBG semiconductors and their potential to change and improve induction heating technology in the next years.
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Keywords
Abstract
Purpose
This work aims to investigate the modifications in a transistor behavior after hot carrier injection processes from the integrated junction.
Design/methodology/approach
A high voltage is applied across the drain‐source contacts, so a reverse current is induced through the integrated junction and defects are then created.
Findings
The results point out to a dependence of the VDMOSFET reliability on the operating conditions which could induce parasitic effects on the structure. Induced defects alter the form of several MOSFET characteristics.
Originality/value
A new method of degradation is presented along with a series of characterization techniques‐based electrical parameters variations.
Details