Study by Imec, University of Antwerp, KULeuven, MathAM-OIL and Synopsys QuantumATK Team
Pourtois et al., ESC Trans. 80, 303 (2017)
Imec and collaborators used QuantumATK to investigate the doping-dependence of contact resistance and intrinsic processes that limit the resistance of the TiSi (amorphous)/Si contact. DFT+NEGF was used to calculate I-V curves, local density of states and contact resistance as a function of the doping concentration . This work demonstrates that the intrinsic contact resistivity saturates with the doping concentration. Furthermore, it is shown that as the doping concentration increases, the impact of interface composition decreases and the contact resistance starts to be dominated by intrinsic properties of the metal and the semiconductor, such as their effective masses and Fermi energies. Authors also suggest that metals with a high effective mass, such as, for example, Sc, could be used to maximize the transmission probability of electron injection and thus reduce the metal-semiconductor resistance.