The commercial piezoresistive pressure sensors are limited to operate up to a maximum temperature of 125 ℃ due to junction leakage. In addition, there are very limited studies present on the irradiation-induced degradation of piezoresistive pressure sensor performance. Keeping these limitation in view, this work focuses with parametric study of sensor performance using simulation, fabrication and characterization (under elevated temperature and radiation exposure) of the MEMS technology based piezoresistive pressure sensor. The design parameters are selected based on the simulation studies for the design and fabrication of mask followed by the fabrication of the MEMS technology based pressure sensor. The diffused and SOI piezoresistors technologies were adopted for fabrication of piezoresistive pressure sensor. The piezoresistive pressure sensor prototypes have been investigated under elevated temperature (up to 200 ℃). The degradation in pressure responses are 11 % at 100 ℃ and 19 % at 200 ℃ for diffused and SOI technologies based piezoresistive pressure sensors. The diffused piezoresistor based pressure sensor showed inconsistent response after 100 ℃ whereas SOI technology based pressure sensor performance did not degrade up to 200 ℃. A suitable compensation circuit has been recommended to correct the offset voltage and temperature sensitivity for these sensors. Furthermore, irradiation induced degradation of commercial piezoresistive pressure sensors for two cases have been carried out. Case I, a packaged piezoresistive pressure sensor with silicone oil has been selected for the performance investigation which showed significant degradation in sensitivity and offset voltage. Case II, a packaged piezoresistive pressure sensor without silicone oil has been selected for the performance investigation which showed no degradation in the sensitivity, however, a significant degradation in offset voltage was recorded.
Vinod Belwanshi is working in the field of MEMS technology based sensors and actuators since August 2013. He has designed and developed the pressure sensor using MEMS technology to understand the degradation in its performance under elevated temperature and irradiation. He has worked under the supervision of Dr. Anita Topkar, Scientific Officer, Bhabha Atomic Research Centre, Mumbai, India and completed the requirement for doctoral degree. He has carried out his fabrication of designed pressure sensor at CSIR-Central Electronics Engineering Research Institute, Pilani, India under the mentorship of Dr. Jamil Akhtar, Chief Scientist and Head, Flexible and Non-Silicon Electronics Group. Prior to joining the PhD program, he was working as a trainee engineer at Atos India Pvt. Ltd. Pune, India. He has a master degree in instrumentation from Indian Institute of Technology, Kharagpur, India under the supervision of Prof. S. Mukhopadhyay, Department of Electrical Engineering and Prof P.K. Das, Department of Mechanical Engineering. He has also served at CSIR-National Geophysical Research Institute, Hyderabad, India as a Project Assistant and worked in the field of seismic data acquisition and maintenance of geophysical instruments. He has completed his B.E. in Electronics and Instrumentation from Shri GS Institute of Technology and Science, Indore, India. His current research interests are analytical modelling, design optimization, simulation, fabrication and characterization of MEMS technology based sensors and actuators.