Silicon carbide sensor

Svenningstorp, H.,Tobias, E, Lundstrom, L, Salomonsson, E, Martensson, R, Ekedahl, L. G. and Spetz, A. L. (1999) Influence of catalytic reactivity on the response of metal-oxide-silicon carbide sensor to exhaust gases . Sensors and Actuators B-Chemical, 57(1-3), 159-165. 

Temperature measurements, (a) Platinum wire sensor measurements and (b) silicon carbide filaments. 

We recently published a chapter in the book Silicon Carbide Recent Major Advances by Choyke et al. [19] that describes SiC gas sensor applications in detail. In this book, we emphasize device properties applications are only briefly reviewed at the end. The device and gas sensing properties of various field-effect chemical gas sensing devices based on SiC are described, and other wide bandgap material devices are reviewed. The detection principle and gas response is explained, and the buried channel SiC-FET device is described in detail. Some special phenomena related to the high-temperature influence of hydrogen at high temperature are also reported. 

The metal-insulator-silicon carbide MISiC sensors function over a large temperature range, 100-700°C. Their gas response can be divided into two different temperature regimes with the break-over point around 600°C. 

An experiment with a dilute ceramic suspension was made as follows A very small quantity of silicon carbide particles (d 6 /xm) was dissolved in silicon oil ( 350mPas). The suspension was pumped at high pressure through a glass capillary (d = 0.6 mm). The experimental setup is shown in Fig. 3. The velocities of the silicon carbide particles in the capillary are detected by an optical sensor. From these data, the statistics of the particles velocities is calculated. Due to the optical properties of the sensor, the particles are only detected in a wedge-like sector of the cross-section of the capillary. The measured velocity distribution of the particles (Fig. 4) depends on the shape of this sector and, additionally, on the measuring tolerances of the sensor. 

Silicon carbide-based sensors can operate at higher temperatures (above 600°C) because of a wide band gap and low intrinsic carrier concentration availability of SiC. Taking advantage of this trait, silicon carbide semiconductors have been used... 

In the best-case situation, both types of microcantilever sensors would be grouped in an array to provide a cross platform of sensitive and selective explosive detection system. Additional co-funded (TSA/ATF) work is eurrently on going in materials development for novel microeantilevers. This involves R D of silicon carbide (SiC) based cantilevers, for improvements in material properties (e.g., less fragile eompared to silicon) and to provide a platform for wide band gap type materials, like aluminum nitride (AIN). With an AlN/SiC based cantilever, the sensor can now work in the piezoeleetric resonator mode, providing enhance response and henee sensitivity to the analyte, along with a direct measurement by frequeney/resistance response, versus the more complex optieal deteetion... 

Recent trends in silicon carbide (SiC) and graphene-based gas sensors... 

Hwang, E. H., Adam, S. and Das Sarma, S. (2007),Transport in chemically doped graphene in the presence of adsorbed molecules. Physical Review B, 76,195421. Inone, H., Andersson, M., Ynasa, M., Kida, T, Lloyd Spetz, A. and Shimanoe, K. (2010), CO2 sensor combining a metal-insulator silicon carbide (MISiC) capacitor and a binary carbonate. Electrochemical and Solid-State Letters, 14(1), J4-7. Doi 10.1149/1.3512998... 

Nakagomi, S., Tobias, R, Baranzahi, A., Lundstrom, I., Martensson, P. and Lloyd Spetz, A. (1997), Influence of carbon monoxide, water and oxygen on high temperature catalytic metal-oxide silicon carbide structures. Sensors and Actuators 5,45,183-91. 

Spetz, A., Arbab, A. and Lundstrom, I. (1992), Gas sensors for high temperature operation based on metal oxide silicon carbide (MOSiC) devices, in Proceedings of Eurosensors VI, San Sebastian, Spain, 19-23. 

Silicon carbide Schottky diode hydrogen sensor... 

Connolly, E. J., O Halloran, G. M.,Pham, H.T. M.,Sarro, P. M. and French,P. J. (2002) Comparison of porous silicon, porous polysUicon and porous silicon carbide as materials for humidity sensing apphcations Sensors and Actuators a-Physical, 99(1-2), 25-30. 

Potentially useful single crystal HP-LCVD fibers include hafnium boride and tantalum carbide and have projected service temperatures ranging from 2170 to 2715 C. Presently envisioned applications include the potential use of these fibers as consumable sensors to monitor rocket exhaust temperatures. Other HP-LCVD sensor fibers, including Si, Ge and ZnSe, (Figure 15), promise to offer high value in premium automotive and medical sensor systems. Single crystal HP-LCVD germanium [20] and silicon carbide [21] fibers can now also become available for exploration. In summary, the HP-LCVD process is an ideally suited tool for the rapid fabrication and evaluation, without extensive process research, of test samples of potentially new fiber candidates for structural and sensor uses. 

Buriak JM, Stewart MP, Geders TW, Allen MJ, Choi HC, Smith J, Raftery D, Canham LT (1999) Lewis acid mediated hydrosilylation on porous silicon surfaces. J Am Chem Soc 121 11491-11502 Connolly EJ, O Halloran GM, Pham HTM, Sarro PM, French PJ (2002) Comparison of porous silicon, porous polysilicon and porous silicon carbide as materials for humidity sensing applications. Sens Actuators B 99 25-30 Ftirjes P, Kovdcs A, Cs D, Addm M, Muller B, Mescheder U (2003) Porous silicon-based humidity sensor with interdigital electrodes and internal heaters. Sens Actuators B 95 140-144 Hedrich F, BiUat S, Lang W (2000) Structuring of membrane sensors using sacrificial porous silicon. Sens Actuators A 84 315-323... 

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