A proposal of trapezoid mesa trench MOS barrier Schottky rectifier

Abstract

We propose a new structure of Schottky rectifier, named trapezoid mesa trench MOS barrier Schottky rectifier (TM-TMBS). By 2D numerical simulations, both forward and especially better reverse I-V characteristics, including higher breakdown voltage and lower leakage current, were demonstrated and explained comparing to regular TMBS as well as conventional planar Schottky rectifier.

High-voltage 4H-SiC trench MOS barrier Schottky rectifier with low forward voltage drop using enhanced sidewall layer

“…Therefore, the 4H-SiC TMBS rectifier should be designed such that the trench corner electric field crowding phenomenon is minimized. [26][27][28][29] The ESL-TMBS rectifier has another peak electric field caused by the difference in doping concentration between the ESL layer and the n-drift region, which mitigates the trench corner electric field crowding phenomenon. These effects not only allow the ESL-TMBS rectifier to have a higher breakdown voltage and an oxide shielding effect, but also improve its reliability.…”

Trapezoid mesa trench metal-oxide semiconductor barrier Schottky rectifier: an improved Schottky rectifier with better reverse characteristics

“…It was mentioned that the breakdown of a TMBS occurs near the bottom of the trench. [9] However, as revealed in our previous work, [20] the field crowding near the trench corner of the TMBS causes the difficulty in achieving a more uniform electric field, thus a higher breakdown voltage. In this work, enlightened by the improved design of the UMOS power device, [21] we propose an improved TMBS structure-trapezoid mesa TMBS (TM-TMBS) to restrain the high electric field peak at the corner, thus to achieve better reverse characteristics.…”

Improved trench MOS barrier Schottky rectifier by dielectric engineering

“…Some improved TMBS rectifier structures have been proposed, such as 100 V TMBS rectifier using thick oxide TMBS layer [3], a low forward drop high-voltage TMBS rectifier with linearly graded doping TMBS profile [4], improvement of TMBS rectifier by using high-energy counter-doping trench-bottom implantation [5], a proposal of trapezoid mesa TMBS rectifier [6], improved TMBS rectifier which utilises the upper half of the trench sidewall as an active area [7]. The improved TMBS rectifier structures [3][4][5][6] are proposed for enhancing blocking voltage and the forward characteristics are not improved. The improved TMBS [7] structure improves forward voltage drop by 20% while the reverse leakage current is also increased several times.…”