SiC or V-element nitrides?

In addition to SiC, the V-element nitride sector is often cited for power electronics applications. In addition to gallium nitride (GaN), it includes the associated element nitrides (AlN and InN) and their alloys (AlGaN and InGaN). In this sector, GaN is a direct-gap semiconductor, and as such has long since supplanted SiC for all blue emission applications. Paradoxically, however, this is still a buoyant market for SiC, whose substrates are often used to enhance the performance of super-bright components.

For power electronics applications proper, however, GaN has three major drawbacks: i°) the absence of native oxide (which penalizes the manufacture of MOS devices); ii°) the absence of large-scale bulk GaN substrates (which limits the thickness of active layers to ~ 10 µm) and, lastly, iii°) a thermal conductivity well below that of SiC (1.3 W/cm.K, compared with...