Optimized Analysis of Sensitivity and Non-Linearity for PDMS–Graphene MEMS Force Sensor

Abstract

The aim of this paper is to analyze and evaluate the sensitivity and non-linearity of graphene piezoresistive MEMS force sensor by optimizing its geometrical parameters. In this work, important factors affecting sensitivity and non-linearity were identified such as geometrical dimensions of microcantilever, modulus of elasticity of material, shape, placement, doping concentration, and dimensions of piezoresistors. Based on the selection of factors, Taguchi optimization method was employed for finding an optimal combination of microcantilever and piezoresistor dimensions. The optimized model of force sensor was designed with the aid of obtained dimensions of microcantilever and piezoresistors. For designing and simulation, COMSOL Multiphysics® 5.3a software is used. The major findings revealed that the designed sensor possess a high sensitivity of 3.93 mV/µN in an operating range from 0 to 106 µN with 0.0092% of non-linearity. An important feature of flexibility is introduced in the sensor by incorporating the novel combination of Polydimethylsiloxane (PDMS) as a flexible substrate and graphene as a flexible piezoresistor. The originality also lies in the area of the cumulative analysis of various input factors which are listed above altogether in one platform.

KEYWORDS:

• Flexibility
• Graphene
• MEMS force sensor
• Non-linearity
• Piezoresistors
• Sensitivity

Acknowledgements

Sincere gratitude is extended to the Multiscale Simulation Research Center (MSRC), Manipal University Jaipur for providing us access to the COMSOL Multiphysics^® 5.3a version software. The Dean FOE, Prof. Jagannath Korodi and Director SEEC, Prof. Jamil Akhtar are thanked for their constant support and encouragement. The first author (Monica Lamba) would like to thank MUJ administration for the financial support in the form of TAship. Mr Premraj Kashyap Managing Director, KYB Conmat Pvt. Ltd. is also thanked for his valuable inputs.

Additional information

Notes on contributors

Monica Lamba

Monica Lamba received her MTech degree in electronics and communication engineering from UCOE Punjabi University Patiala, Punjab, India in 2014. Currently, she is pursuing her PhD in electronics and communication engineering from Manipal University Jaipur, Rajasthan, India. Her current research interests include MEMS sensor designing and simulation for microbotic applications. Email: [email protected]

Himanshu Chaudhary

Himanshu Chaudhary is working as an associate professor, in the Department of Electronics and Communication Engineering, Manipal University Jaipur, Rajasthan. He received his PhD degree from the Department of Electrical Engineering from IIT Roorkee in 2015 in the area of robotics and received his ME degree in automatic controls & robotics in 2000 from Electrical Engineering Department of Maharaja Sayajirao University, Baroda, Gujarat, India. He has over 15 years of teaching and industry experience in the area of electronics and communication engineering, computer science engineering in various industries and universities including CONMAT engg. Baroda, Gujarat, India and BITS Pilani, Rajasthan, India. His current field of interests are robotics, embedded systems, MEMS, soft computing techniques, and machine learning.

Kulwant Singh

Kulwant Singh is working as an associate professor in the Department of Electronics and Communication Engineering, Manipal University Jaipur, Rajasthan. He received his PhD degree from National Institute of Technology Calicut (NITC), India in collaboration with Central Electronics Engineering Research Institute (CSIR-CEERI), Pilani, India in 2015 and MTech from School of Engineering, Tezpur University, India in 2008. He has 14 years of experience in academic/R&D sectors from different organizations. He has worked on various projects of microelectronics/MEMS device design and fabrication, and published various research articles in SCI indexed journals. His research areas of interest are semiconductor device technology, MEMS/NEMS sensors, energy and biosensors.Email: [email protected]