Design of SiC-Doped Piezoresistive Pressure Sensor for High-Temperature Applications.

Tomasz Wejrzanowski,Tomasz Plocinski,Janusz Józef Bucki,Emil Tymicki,Teck Leong Tan

doi:10.3390/s21186066

Abstract

Within these studies the piezoresistive effect was analyzed for 6H-SiC and 4H-SiC material doped with various elements: N, B, and Sc. Bulk SiC crystals with a specific concentration of dopants were fabricated by the Physical Vapor Transport (PVT) technique. For such materials, the structures and properties were analyzed using X-ray diffraction, SEM, and Hall measurements. The samples in the form of a beam were also prepared and strained (bent) to measure the resistance change (Gauge Factor). Based on the results obtained for bulk materials, piezoresistive thin films on 6H-SiC and 4H-SiC substrate were fabricated by Chemical Vapor Deposition (CVD). Such materials were shaped by Focus Ion Beam (FIB) into pressure sensors with a specific geometry. The characteristics of the sensors made from different materials under a range of pressures and temperatures were obtained and are presented herewith.

Highlights

The piezoresistive effect has been known since 1856 thanks to the discovery of LordKelvin (William Thomson) [1]
It describes the electrical resistivity change in a material in response to mechanical deformation. This property is frequently quantified by the so-called gauge factor (GF), which represents the fractional change in the resistance per unit strain: Accepted: 6 September 2021
The 4H- and 6H-silicon carbide (SiC) crystals with various dopant concentrations of nitrogen, boron, and scandium were fabricated by the Physical Vapor Transport (PVT)

Summary

Introduction

The piezoresistive effect has been known since 1856 thanks to the discovery of Lord. Kelvin (William Thomson) [1]. It describes the electrical resistivity change in a material in response to mechanical deformation. This property is frequently quantified by the so-called gauge factor (GF), which represents the fractional change in the resistance per unit strain: Accepted: 6 September 2021. Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Methods

Results

Conclusion