Controlled improvement in specific contact resistivity for thermoelectric materials by ion implantation Available to Purchase

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 Ω cm² to 4.5 × 10⁻⁷ Ω cm². Implantation into p-type materials caused specific contact resistivity to decrease from 7.7 × 10⁻⁷ Ω cm² to 2.7 × 10⁻⁷ Ω cm². For implanted thin-film superlattices, the non-implanted values of 1.4 × 10⁻⁷ Ω cm² and 5.3 × 10⁻⁸ Ω cm² precipitously dropped below the detection limit after implantation, ≤10⁻⁸ Ω cm². These reductions in specific contact resistivity are consistent with an increase in tunneling across the contact.