High temperature piezoresistance properties of 6H-SiC ceramics doped with trivalent elements

Piezoresistance coefficient was measured at room and elevated temperatures on 6H-SiC ceramics doped with different amounts of boron, aluminum or gallium. The piezoresistance coefficient increased with increasing the addition within their solid solution limits. The profile of carrier concentrations, lattice constant and piezoresistance coefficient against doping levels were closely related. In few samples piezoresistance coefficient slightly decreased with measurement temperature.