4.5 kV SiC Junction Barrier Schottky Diodes with Low Leakage Current and High Forward Current Density

Abstract

High-voltage 4H-SiC Junction Barrier Schottky diodes with a reverse breakdown voltage of over 4.5 kV and a turn-on voltage below 1 V have been fabricated. They achieved a forward current of 5 A at a forward voltage drop of 1.8 V and 20 A at 4.2 V. A low reverse leakage current of 0.3 μA at 1.2 kV and 37 μA at 3.3 kV was measured. The chip size was 7.3 mm x 7.3 mm, the active area 0.25 cm2 and the diode was able to handle a repetitive pulse current density of over 300 A/cm2 without degradation. Floating field rings in combination with a field-stop ring were used as edge termination to reach 73 % of the theoretical breakdown voltage. The epitaxial layer was 32 μm thick, with a nitrogen doping concentration of 1 x 1015 cm-3. The JBS diodes have been manufactured in a 100 mm SiC prototyping line, using well established processing technology, to achieve cost-efficient devices.

Influence of Triangular Defects on the Electrical Characteristics of 4H-SiC Devices

“…Junction barrier Schottky (JBS) diodes and vertical diffused metal oxide semiconductor (VDMOS) transistors [2] were fabricated on PL-scanned wafers. Processing details of the JBS diodes were previously described [3]. Fabrication of the VDMOS devices was achieved with these modules: alignment marks, implantation (p well , p + , n + ), post implantation anneal, passivation oxide, gate oxidation, poly-Si gate, inter metal dielectric, metallization and passivation.…”

(Invited) Challenges the UWBG Semiconductors AlGaN, Diamond, and Ga2O3Must Master to Compete with SiC and GaN HPE Devices

“…Schottky junction and reduce the leakage current but this also makes them more resistive (26) are made possible by a mature implant and annealing procedure for the p-type dopant. Recently, it was demonstrated that they were able to reproducibly block 4.5 KV (28). In the past it was shown they could block up to 10 KV (29).…”

3.3 kV SiC JBS diode configurable rectifier module

“…the PiN part). Promising results, both in terms of on-state performance and ensuring repetitive characteristics among different manufacturing lots, were obtained with the deposition of 100 nm TiAl3 on the front-side and rapid thermal annealing the wafers for 2 min at 980°C [9][10][11].…”

“…This work looks at the development of an uncontrolled diode based rectifier, of common use, for instance, in wind power conversion systems, with the ability to handle repetitive current surges of up to some times the nominal on-state current level [8]. So, to make the most of Schottky and p-i-n junction diode features, high voltage 4H-SiC Junction Barrier Schottky (JBS) diodes were designed and fabricated, with a nominal breakdown voltage in excess of 3.3 kV [9]. The devices were packaged in a multi-chip rectifier module configurable as both full-bridge and half-bridge rectifier topology (single phase).…”