On the Suitability of 3C-Silicon Carbide as an Alternative to 4H-Silicon Carbide for Power Diodes

Abstract

Major recent developments in growth expertise related to the cubic polytype of Silicon Carbide, the 3C-SiC, coupled with its remarkable physical properties and the low fabrication cost, suggest that within the next years, 3C-SiC devices can become a commercial reality. Inevitably, a comparison to the most well developed polytype of SiC, the 4H-SiC, should exist. It is therefore important to develop Finite Element Method (FEM) techniques and models for accurate device design, analysis and comparison. It is also needed to perform an exhaustive investigation with scope to identify which family of devices, which voltage class and for which applications this polytype is best suited. In this work, we validate the recently developed Technology Computer Aided Design (TCAD) material models for 3C-SiC and those of 4H-SiC with measurements on power diodes. An excellent agreement between measurements and TCAD simulations was obtained. Thereafter, based on this validation, 3C-and 4H-SiC vertical power diodes are assessed, to create trade-off maps. Depending on the operation requirements imposed by the application, the developed trade-off maps set the boundary of the realm for those two polytypes and allows to predict which applications would benefit once electrically graded 3C-SiC becomes available.

3C-SiC-on-Si MOSFETs: Overcoming Material Technology Limitations

“…The unipolar limit for 3C-SiC is calculated with (7), as the trade-off relationship between the specific onresistance of a drift layer (forward operation mode) and the corresponding breakdown voltage (reverse operation mode) [32]. The expressions regarding the 𝑉 𝐵𝑅 3𝐶−𝑆𝑖𝐶 and 𝐸 𝐶𝑟 3𝐶−𝑆𝑖𝐶 derived from the Power formula for 3C-SiC [33] as a function of the doping concentration, have been deployed in (7). The Power formula for 3C-SiC and, hence, the derived expressions for the critical field and the breakdown voltage assume NPT structures for which all the drift is ideally depleted.…”

Status and Prospects of Cubic Silicon Carbide Power Electronics Device Technology

“…The resulting structure is a pure zinc-blende exhibiting an energy band gap of 2.3–2.4 eV [ 8 ], lower compared to other major SiC polytypes, but with a higher electron mobility and saturation velocity owing to its higher degree of symmetry. Although 3C-SiC has a smaller energy bandgap compared to its wide bandgap counterparts such as 4H-SiC and GaN, this material displays isotropy for many of the desired power device material characteristics such as avalanche coefficients and high electron mobility [ 9 , 10 ]. Another advantage of 3C-SiC is its relatively large thermodynamic stability meaning that bulk material can be grown at reduced thermal budgets (below 1500 °C).…”

Laser Power Converter Architectures Based on 3C‐SiC with Efficiencies >80%

“…[ 30 ] Efforts are being made to obtain high‐quality cubic 3C crystals because of the high electron mobility and isotropic properties, [ 31 ] and the fact that 3C can be grown on large commercially available Si wafers, notably reducing fabrication costs. [ 32 ] SiC has not been considered for solar PV applications due to its high energy gap and poor solar spectrum absorption. [ 33 ] However, this material becomes very interesting in the context of laser power converters due to the properties previously mentioned.…”