Multiple P-Type SiC Micro-Island with Multi-Step as Termination for 4H-SiC Schottky Barrier Diode

This article proposes a termination design for 4H-SiC Schottky Barrier Diodes (SBDs) that integrates uniformly distributed multiple P-type micro-island with multi-step. This design eliminates the need for high-energy ion implantation, reducing process costs. By optimizing the length <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{L}_{\mathrm{P}})$</tex>, spacing <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{S}_{\mathrm{P}})$</tex>, and number <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{N}_{\mathrm{P}})$</tex> of the micro-island, along with the step lengths <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{L}_{\text{step}})$</tex> and numbers <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{n}_{\text{step}})$</tex> in the end relaxation region, the device reverse performance can be effectively improved. The study demonstrates that with an <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{L}_{\mathrm{P}} =12$</tex> μm, <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{S}_{\mathrm{P}} =3$</tex> μm, <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{N}_{P}=5, \mathrm{L}_{\text{step}}=8\mu \mathrm{m}$</tex>, and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{n}_{\text{step}}=3$</tex> the electric field distribution is more uniform under a reverse voltage of 1200 V, achieving a terminal efficiency exceeding 90%. Furthermore, this configuration reduces the terminal area by over 16% compared to a structure comprising solely uniformly distributed P -type micro-islands.