Nanomeghyas

Nanomeghyas

Structural variations in MESFET for improving electrical characteristics

Document Type : Original Article

Abstract
In this paper, a new structure of the SiC metal-semiconductor field effect transistor (SiC-MESFET) is presented. In the proposed structure of the upper part of the channel under the gate, a semiconductor with very low impurity density is used and at the bottom of the channel, a semiconductor with a high impurity density is used. The most important electrical characteristics of the proposed transistor such as breakdown voltage, drain current, threshold voltage, electric field and gate capacitor are simulated and compared with these characteristics in conventional transistor. According to the simulation results, the proposed structure reduces the maximum electric field in the channel and thus increases the breakdown voltage from 127 V to 136.5 V compared to the conventional structure. The new structure also increases the saturation drain current by 30% compared to the conventional structure. The high density of impurities in the channel bottom causes a negative shift in the threshold voltage in the provided transistor. According to the obtained results and increasing the drain current and the breakdown voltage, the proposed transistor can be used in high power applications.
Keywords
Metal semiconductor field effect transistor (MESFET)
Drain current
Breakdown voltage
Threshold voltage
Gate capacitance
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  • Receive Date 06 July 2021
  • Revise Date 07 September 2021
  • Accept Date 29 August 2021