Selective Chemical Vapor Deposition Approach for Sb<sub>2</sub>Te<sub>3</sub> Thin Film Micro-thermoelectric Generators
Daniel W. Newbrook, Stephen P. Richards, Victoria K. Greenacre, Andrew L. Hector, William Levason, Gillian Reid, C.H. de Groot, Ruomeng Huang
Abstract
Micro-thermoelectric generators are attractive for autonomous sensor systems. This work reports an approach for fabricating thin film micro-thermoelectric generators via selective chemical vapor deposition. The approach utilizes our single-source precursors, which enable the production of high-quality thermoelectric materials, as exemplified by Sb2Te3 in this work. It also allows great control over the thermoelectric properties of the as-deposited Sb2Te3 by simply varying the deposition temperature. A competitive power factor of 16.5 μW/(cm·K2) can be obtained for a Sb2Te3 film deposited at 364 °C, with the highest estimated ZT value of 0.65. The selective deposition over the conductive TiN surface enables the fabrication of a prototype single-leg thermoelectric generator, which produces a maximum power of 0.27 nW, with a temperature gradient of only 0.11 K while reducing 87% of tellurium consumption.