@article{Akiyama:170303, title = {Piezoresistive n-Type 4H-SiC Pressure Sensor with Membrane Formed by Mechanical Milling}, author = {Akiyama, Terunobu and Briand, Danick and de Rooij, Nico}, publisher = {Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa}, journal = {Proceedings of IEEE Sensors}, volume = {1}, pages = {222-225}, year = {2011}, abstract = {A 4H-SiC pressure sensor with piezoresistive transducers, for harsh environment applications, e.g., high temperature (~650°C) and/or in corrosive chemicals is presented. The sensing membrane, 1 mm in diameter and 50 µm in thickness, was formed by milling (drilling) a bulk single crystal SiC wafer. Both transverse and longitudinal piezoresistors were formed on the membrane out of an n-type SiC epitaxial layer. Ohmic contacts were obtained with Ta/Ni/Pt metallization followed by annealing at 1000°C for 20 min. The sensor was assembled on a small board and characterized under hydrostatic pressures up to 60 bar at room temperature. The obtained pressure sensitivity was 268 µV/V/bar. The sensor chip was exposed in air at 600°C for 165 hours and changes in bridge resistance were measured.}, url = {http://infoscience.epfl.ch/record/170303}, }