Current Status in Fabrication, Structural and Transport Property Characterization, and Theoretical Understanding of Bi2Te3 / Sb2Te3 Superlattice Systems

Roughly a decade ago an outstanding thermoelectric Figure of merit ZT of 2.4 was published for nanostructured Bi2Te3/Sb2Te3-based thin film superlattice (SL) structures. The results strongly fueled and renewed the interest in the development of efficient novel nanostructured thermoelectric materials. Several attempts were made to reproduce and improve the properties by using different methods, for example by replacing the cost-intensive metal organic chemical vapor deposition (MOCVD) used to deposit the superlattices. This method-oriented article shall give a critical overview over the most recent advances concerning growth, structural and electrical characterization, and theoretical understanding of Bi2Te3/Sb2Te3 SL systems. Previously reported data as well as new results from our groups are presented. Selected additional results from closely related Bi2Te3- and Sb2Te3-based nanolayered systems are also presented to enhance the discussion.