Power Electronics Based on Wide-Bandgap Semiconductors: Opportunities and Challenges

Abstract

The expansion of the electric vehicle market is driving the request for efficient and reliable power electronic systems for electric energy conversion and processing. The efficiency, size, and cost of a power system is strongly related to the performance of power semiconductor devices, where massive industrial investments and intense research efforts are being devoted to new wide bandgap (WBG) semiconductors, such as silicon carbide (SiC) and gallium nitride (GaN). The electrical and thermal properties of SiC and GaN enable the fabrication of semiconductor power devices with performance well beyond the limits of silicon. However, a massive migration of the power electronics industry towards WBG materials can be obtained only once the corresponding fabrication technology reaches a sufficient maturity and a competitive cost. In this paper, we present a perspective of power electronics based on WBG semiconductors, from fundamental material characteristics of SiC and GaN to their potential impacts on the power semiconductor device market. Some application cases are also presented, with specific benchmarks against a corresponding implementation realized with silicon devices, focusing on both achievable performance and system cost.

New FOM-Based Performance Evaluation of 600/650 V SiC and GaN Semiconductors for Next-Generation EV Drives

“…During the last decades, the development of Si semiconductor technology for power electronic applications has been rapidly approaching the theoretical performance limits of the material itself [14]- [18]. To overcome these limits, new wide-bandgap (WBG) semiconductor materials have been developed and are rapidly replacing Si in several applications, due to their superior performance in terms of blocking voltage, conduction characteristics, switching speed, operating temperature and overall footprint per conducted current [14]- [18]. At present, the most developed and established WBG materials in power electronics are silicon carbide (SiC) and gallium nitride (GaN).…”

“…In the near future, two key enabling technologies will play a significant role in addressing these challenging requirements: novel drive inverter topologies (i.e., different from the conventional two-level voltage-source inverter) [10]- [13] and modern wide bandgap (WBG) semiconductor devices [14]- [18]. Fig.…”

“…In this work, all considered drive inverter topologies only adopt semiconductor devices rated at 600/650 V. Both the multi-level approach in (b), (c) and the current-source approach in (d) allow to significantly reduce the high-frequency voltage/current stress on the supplied machine [10]- [13], thus limiting the PWM-induced losses [7]. To best exploit these new inverter architectures, modern 600/650 V silicon carbide (SiC) and gallium nitride (GaN) semiconductor devices are excellent candidates, as they significantly outperform traditional silicon (Si) devices of the same voltage class [14]- [18]. Even though WBG devices currently pose many practical challenges, including PCB layout, gate driving, increased EMI, cable reflections, machine bearing currents and motor insulation stress [3], they feature outstanding properties such as low specific onstate resistance, fast switching and high-temperature operation capability, which unlock unprecedented performance at the converter level [3].…”

Evaluation of the thermal stability of TiW/Cu heterojunctions using a combined SXPS and HAXPES approach

“…Power semiconductor device technologies are at the core of the power-train and battery-management systems in hybrid and electric vehicles. [1][2][3] With the continuing global efforts to popularize the electrification of the automotive industry, there is incentive toward developing devices with smaller feature sizes, improved reliability, and higher power capacity. These targets are being realized through the replacement of aluminum (Al) topside metallization connections in these devices with copper (Cu).…”

Medium Voltage Power Switch in Silicon Carbide—A Comparative Study

“…Silicon Carbide power devices have a substantial impact on power electronics [1][2][3] employed in energy conversion and management systems, as they offer lower on-state resistances and higher switching speeds in comparison to Silicon (Si) counterparts, and more efficient or/and more compact power converters can be designed [4]. This conclusion may be drawn from a number of research works and industrial applications in various fields where mostly low voltage (650 V to 1200 V) SiC diodes and transistors can be found.…”