Enhanced thermoelectric figure of merit of individual Si nanowires with ultralow contact resistances

• Published in: Nano energy 2020-01, Vol.67, p.104191, Article 104191
• Main Authors: Gadea Díez, Gerard, Sojo Gordillo, Jose Manuel, Pacios Pujadó, Mercè, Salleras, Marc, Fonseca, Luis, Morata, Alex, Tarancón Rubio, Albert
• Format: Article
• Language: English
• Subjects: Integration; Micro/nano generator; Nanowires; Silicon; Thermoelectric
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2019.104191

Low-dimensional silicon-based materials have shown a great potential for thermoelectric applications due to their enhanced figure of merit ZT and high technology compatibility. However, their implementation in real devices remains highly challenging due to the associated large contact resistances (thermal and electrical). Herein we demonstrate ultralow contact resistance silicon nanowires epitaxially grown on scalable devices with enhanced ZT. Temperature dependent figure of merit was fully determined for monolithically integrated individual silicon nanowires achieving a maximum value of ZT = 0.2 at 620 K. Sidewise, this work accounts for the first time nearly zero thermal and electrical contact resistances in monolithically integrated bottom-up nanowires. [Display omitted] •Silicon nanowires were grown between two platforms emulating micro-machined devices.•Full thermoelectric characterization was carried out in boron-doped silicon nanowires.•Thermal and electrical conductivities were simultaneously measured from the same nanowires.•Results obtained show virtually null electrical and thermal contact resistances.•Transparent interfaces are the key for the implementation of nanowires in devices.