Theoretical study on the improvement of the doping efficiency of Al in 4H-SiC by co-doping group-IVB elements

The p-type doping efficiency of 4H silicon carbide (4H-SiC) is rather low due to the large ionization energies dopants. Such an issue impedes exploration full advantage 4H-SiC for semiconductor devices. In this letter, we show that co-doping group-IVB elements effectively decreases energy most widely used dopant, i. e., aluminum (Al), through Coulomb repulsion between levels and Al in 4H-SiC. Among Ti has prominent effectiveness. by nearly 50%, leading a value as ~ 0.13 eV. As result, rate with up 5 times larger than without at room temperature when concentration 1018 cm-3. This work may encourage experimental group-IB such significantly improve