SiGe nanowire arrays based thermoelectric microgenerator. (March 2019)

• Record Type: Journal Article
• Authors: Donmez Noyan, Inci; Gadea, Gerard; Salleras, Marc; Pacios, Merce; Calaza, Carlos; Stranz, Andrej; Dolcet, Marc; Morata, Alex; Tarancon, Albert; Fonseca, Luis
• Is Part Of: Nano energy. Volume 57(2019)
• Page Start: 492
• Page End: 499
• Publication Date: 2019-03
• Subjects: SiGe nanowires -- Thermoelectric micro/nanogenerator -- MEMS -- Energy harvesting -- VLS-CVD; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2018.12.050
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Thermoelectric micro/nanogenerators (µTEGs) are potential candidates as energy harvesters to power IoT sensors. This study reports on a thermoelectric micro/nanogenerator with a planar architecture built by silicon micromachining technologies that uses silicon-germanium (SiGe) nanowire (NW) arrays as thermoelectric material. The growth of bottom-up NW arrays by means of Chemical Vapour Deposition - Vapour Liquid Solid growth (CVD-VLS) and their monolithic integration into prefabricated microplatforms are presented. It is shown that SiGe NWs based µTEGs can harvest 7.1 μW/cm 2 without any additional heat exchanger, when there is a waste heat source available at a temperature of 200 °C. Since the required power density for many sensing applications is in the range of 10–100 μW/cm 2 the results obtained in this work are close to meet expectations. Graphical abstract: fx1 Highlights: Energy harvesting is in high demand for powering IoT devices. Proposed device is compatible with Si microtechnologies and enabling mass production. Proposed device smartly combines top-down and bottom-up technologies. SiGe nanowires are integrated into thermal generator device for the first time. Low k of SiGe enabled good thermal isolation and high power densities.