Experimental and numerical analyses of high voltage 4H-SiC junction barrier Schottky rectifiers with linearly graded field limiting ring

Abstract

This paper describes the successful fabrication of 4H-SiC junction barrier Schottky (JBS) rectifiers with a linearly graded field limiting ring (LG-FLR). Linearly variable ring spacings for the FLR termination are applied to improve the blocking voltage by reducing the peak surface electric field at the edge termination region, which acts like a variable lateral doping profile resulting in a gradual field distribution. The experimental results demonstrate a breakdown voltage of 5 kV at the reverse leakage current density of 2 mA/cm 2 (about 80% of the theoretical value). Detailed numerical simulations show that the proposed termination structure provides a uniform electric field profile compared to the conventional FLR termination, which is responsible for 45% improvement in the reverse blocking voltage despite a 3.7% longer total termination length.

Investigations on mesa width design for 4H–SiC trench super junction Schottky diodes

“…Silicon carbide (SiC) unipolar power devices, such as power MOSFETs, JFETs, and SBDs, have been widely approved for their significant advantages in power electronics applications where improved efficiency, power density and higher temperature operation are required. [1][2][3][4] It is understood that for the SiC technology, unipolar devices are the preferred choices for the voltage range below 10 kV, [5] while bipolar devices such as IGBTs may be advantageous for applications higher than 15 kV. In the medium-to-high voltage range (3 kV to 10 kV) applications, emerging silicon carbide unipolar devices, such as SiC-MOSFETs, need to compete with mature Si bipolar devices, such as Si-IGBT.…”

Electrical properties and microstructural characterization of Ni/Ta contacts to n-type 6H–SiC

“…[1][2][3] SiC has been used to fabricate many kinds of power devices, such as high-voltage Schottky barrier diodes (SBDs), metal-semiconductor field-effect transistors (MESFETs), and photoconductive semiconductor switches (PCSSs). [4][5][6] The electrical properties of metal/SiC have an important effect on the performance of a SiC power device. Industrial researchers have also explore the long-term use of SiC devices in radar, aircraft, and military communication systems in extreme environments.…”