New Fabrication Method of Silicon Sub-Micron Beams with Monolithic Contacts for Thermoelectric Transport Properties Analysis

Nanomaterials (Basel). 2022 Apr 12;12(8):1326. doi: 10.3390/nano12081326.

Abstract

Micromachined devices were developed and fabricated using complementary metal-oxide-semiconductor (CMOS)/micro-electro-mechanical systems (MEMS) technology allowing for the analysis of transport properties of silicon sub-micron beams having monolithic contacts. The beams were fabricated by a combination of deep reactive ion etching (RIE) and potassium hydroxide (KOH) etching techniques on standard p and n silicon bulk and silicon-on-insulator (SOI) wafers. Simultaneous fabrication of many devices on one wafer allows for the extraction of statistical information to properly compare the different layers and contacts. Fabricated devices are presented, underlining the feasibility of the proposed microdevice. The methods used to manipulate the geometry and the surface roughness of the single crystalline silicon beams are described. The presented measurement device offers the possibility to determine simultaneously all the main transport values, thermal, and electrical conductivities as well as the Seebeck coefficient.

Keywords: CMOS fabrication; microdevice; silicon; thermoelectric.

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