Effects In MESFETs Research Articles

Physical-topology modeling of silicon/gallium arsenide Schottky transistor of submicron technology LSI

In this paper described researched essentials and physical mechanisms of MESFET on epitaxy layers of GaAs with monocrystalline silicon wafer. Conducted computer modeling of MESFET with p-channel: distributions of potential, volumetric charge, current in channel and its characteristics. Based on conducted modeling discovered new effect in MESFET, shielding of volumetric charge, which sufficiently influences on current distribution in channel.

Gate-Source Distance Scaling Effects in H-Terminated Diamond MESFETs

In this paper, an analysis of gate–source and gate–drain scaling effects in MESFETs fabricated on hydrogen-terminated single-crystal diamond films is reported. The experimental results show that a decrease in gate–source spacing can improve the device performance by increasing the device output current density and its transconductance. On the contrary, the gate–drain distance produces less pronounced effects on device performance. Breakdown voltage, knee voltage, and threshold voltage variations due to changes in gate–source and drain–source distances have also been investigated. The obtained results can be used as a design guideline for the layout optimization of H-terminated diamond-based MESFETs.

An analytical threshold voltage and subthreshold current model for short-channel MESFETs

Short-channel effects on the subthreshold behavior are modeled in self-aligned gate MESFETs with undoped substrates through an analytical solution of the two-dimensional Poisson equation in the subthreshold region. Based on the resultant potential solution, simple and accurate analytical expressions for short-channel threshold voltage, subthreshold swing, and subthreshold drain current are derived. These are then used to develop an expression for minimum acceptable channel length. A comparative study of the short-channel effects in MESFETs with doped and undoped substrates indicates that channel lengths will be limited to 0.15-0.2 mu m by subthreshold conduction. Besides offering insight into the device physics of the short-channel effects in MESFETs, the model provides a useful basis for accurate analysis and simulation of small-geometry GaAs MESFET digital circuits. >