Decoupling of silicon carbide optical sensor response for temperature and pressure measurements

Abstract

Articles you may be interested inDesign optimization of high pressure and high temperature piezoresistive pressure sensor for high sensitivity Rev. Sci. Instrum. 85, 015001 (2014); 10.1063/1.4856455 Development of a simultaneous Hugoniot and temperature measurement for preheated-metal shock experiments: Melting temperatures of Ta at pressures of 100 GPa Rev. Sci. Instrum. 83, 053902 (2012); 10.1063/1.4716459High-pressure and high-temperature x-ray diffraction cell for combined pressure, composition, and temperature measurements of hydrides Rev. Sci. Instrum. 82, 065108 (2011); 10.1063/1.3600668Erratum: "Decoupling of silicon carbide optical sensor response for temperature and pressure measurements" [J.Single crystal silicon carbide is a chemically inert transparent material with superior oxidation-resistant properties at elevated temperatures compared to black polycrystalline silicon carbide substrates. These improved properties make crystalline silicon carbide a good optical sensor material for harsh environments such as combustion chambers and turbine systems. Interferometric optical sensors are orders of magnitude more sensitive than electrical sensors and are proposed for these applications. Silicon carbide itself behaves as a Fabry-Pérot etalon eliminating the need for an external interferometer for any measurement using this silicon carbide as a sensor. The principle of the optical sensor in this study is the temperature-and pressure-dependent refractive index of silicon carbide, which can be used to determine the temperatures and pressures of gases that are in contact with silicon carbide. Interference patterns produced by a silicon carbide ͑4H-SiC͒ wafer due to multiple reflections of a helium-neon laser beam of wavelength of 632.8 nm have been obtained at temperatures up to 500°C and pressures up to 600 psi. The pattern changes for the same gas at different temperatures and pressures and for different gases at the same temperature and pressure. The refractive index at the wafer-gas interface is calculated from the interference pattern and the refractive index gradients with respect to temperature and pressure, respectively, are also determined. Decoupling temperature and pressure using these gradients and the measured reflectivity data are discussed in this paper.

Research and Analysis of a Laser-Type High Temperature Pressure Sensor Based on SiC Diaphragm

“…However, piezoresistive sensors exhibit a strong temperature dependence and suffer from contact resistance variations at elevated temperatures, substantially degrading the sensor performance because the contact resistance variation is indistinguishable from the piezoresistance change caused by the pressure to be sensed [5]. Optical pressure sensors are attractive for high temperature applications due to their advantages of non-contact, high accuracy, high reliability, immunity to electromagnetic interference, and corrosion and oxidation resistance [6]. Among the high accuracy optical sensing technologies, compared with the laser interferometry and optical fiber grating of relatively complicated technology and relatively expensive cost [7], laser triangulation has advantages of simple principle and structure, and low cost.…”

Direct observation of three-dimensional transient temperature distribution in SiC Schottky barrier diode under operation by optical-interference contactless thermometry imaging

“…[20][21][22][23] This method can measure transient temperature change in the optical path on the basis of interference of the light and known thermo-optic coefficient (TOC) values. 24,25) However, a detected temperature by OICT is only from the laser irradiation position, and it is difficult to obtain three-dimensional temperature distribution. In this study, we improved conventional OICT by introducing a high-speed camera (HSC) as the detecting way and extending the simulation model to three dimensions.…”