| Abstract Scope |
Control of carrier polarity and carrier concentration is crucial for realizing high-performance semiconductor devices such as thermoelectrics and solar cells. Substitution with aliovalent ions is the conventional approach for carrier doping; however, there are often cases where the doping does not work effectively. In this talk, I will introduce unusual ion substitution effects and new doping mechanism in layered Sn-based chalcogenides. Although isovalent ion substitution typically does not generate carriers, I will show that isovalent Te substitution at the Se site increases p-type conductivity in SnSe (Adv. Sci. 9, 2105958 (2022).), and that isovalent Pb substitution at the Sn site enables high-density n-type doping in SnS (ACS Appl. Electron. Mater. 6, 8339 (2024).). Additionally, I will present a carrier polarity switching phenomenon in SnSe achieved by switching the substitution sites of Sb (Adv. Funct. Mater. 31, 2008092 (2020).). |