Controlled improvement in specific contact resistivity for thermoelectric materials by ion implantation
To obtain reduced specific contact resistivity, iodine donors and silver acceptors were ion-implanted into n-type and p-type (Bi,Sb)2(Se,Te)3 materials, respectively, to achieve >10 times higher doping at the surface. Implantation into n-type materials caused the specific contact resistivity to decrease from 1.7?×?10?6???cm2 to 4.5?×?10?7???cm2. Implantation into p-type materials caused specific contact resistivity to decrease from 7.7?×?10?7???cm2 to 2.7?×?10?7???cm2. For implanted thin-film superlattices, the non-implanted values of 1.4?×?10?7???cm2 and 5.3?×?10?8???cm2 precipitously dropped below the detection limit after implantation, ?10?8???cm2. These reductions in specific contact resistivity are consistent with an increase in tunneling across the contact.
Taylor, PJ., Maddux, JR., Meissner, G., Venkatasubramanian, R., Bulman, G., Pierce, J., ... Ren, Z. (2013). Controlled improvement in specific contact resistivity for thermoelectric materials by ion implantation. Applied Physics Letters, 103(4), 043902. https://doi.org/10.1063/1.4816054