The material's bandgap determines its thermal stability and breakdown voltage. While Silicon (Si) has been the workhorse with a 1.1 eV bandgap, Wide Bandgap (WBG) materials like Silicon Carbide (SiC, ~3.3 eV) and Gallium Nitride (GaN, ~3.4 eV) allow for much higher critical electric fields.

This section categorizes devices by their structural families and defines their static and dynamic performance metrics.