This document describes 6 potential M.Tech project topics related to MEMS and biomedical engineering. Topic 1 involves modeling and simulating strain-induced mobility in MOSFET sensors. Topic 2 is about modeling and simulating PZT actuation of MEMS resonators for force and mass sensing. Topic 3 focuses on optimizing piezoelectric energy harvester design using COMSOL and MATLAB. Topic 4 is developing a wireless body area network for patient monitoring. Topic 5 aims to create a passive, wirelessly interrogatable sensor network using SAW devices. Topic 6 analyzes recorded brain waves to detect mental disorders and proposes brain waves as a future communication mode.

1. M.Tech. Project Session (2012-13) : Topic #1
Project Title: “Modelling of MOSFET Embedded Sensor for MEMS applications.”
Supervisor: B.S. Panwar.
Objective: Modelling and simulation of strain-induced mobility of a MOSFET as
function of applied stress.
Summary:
Sensing mechanism is one of the most important issues in the field of sensors. Several
transduction mechanisms are available in literature which includes optical detection,
capacitive, piezoelectric and piezoresistive sensing. Recently, embedded transistor technique
[1] is reported in which there is a change in the carrier mobility and drain current of a metal
oxide semiconductor field effect transistor (MOSFET) when stress is applied. A novel
MOSFET pressure sensor was proposed based on the MOSFET stress sensitive phenomenon,
in which the source-drain current changes with the stress in channel region. The use of
piezoresistance model to describe the stress induced carrier mobility change has also been
reported [2-4]. Two MOSFET’s and two piezoresistors were employed to form a Wheatstone
bridge served as sensitive unit in the novel sensor [5]. The use of MOSFETs for strain
sensing will have the following advantages of high sensitivity, low cost, easy integration of
low power CMOS electronics with the MEMS sensors and less complicated signal
conditioning circuitry.
References:
[1] G. Shekhawat, S.H. Tark, and V.P. Dravid, “MOSFET embedded microcantilevers
for measuring deflection in biomolecular sensors,” Science, vol. 311, pp. 1592-95, 2006.
[2] S. Suthram, J.C. Ziegert, T. Nishida, and S.E. Thompson, “Piezoresistance
coefficients of (100) silicon nMOSFETs measured at low and high (~1.5 GPa) channel
stress,” IEEE Electron Device Letters, vol. 28, no. 1, 2007.
[3] Y.L. Tsang, A.G. O’Neill, B.J. Gallacher, and S.H. Olsen, “Using piezoresistance
model with C-R conversion for modelling of strain-induced mobility,” IEEE Electron Device
Letters, vol. 29, no. 9, 2008
[4] J.S. Wang, W.P. Chen, C. Shih, C. Lein, P. Su, Y. Sheu, D.Y. Chao, and K. Goto,
“Mobility modelling and its extraction technique for manufacturing strained-Si MOSFETs,”
IEEE Electron Device Letters, vol. 28, no. 11, 2007.
[5] Z.H. Zhang, Y.H. Zhang, L.Liu, T.L. Ren, “A Novel MEMS Pressure Sensor with
MOSFET on Chip,” IEEE SENSORS Conference, 2008.

2. M.Tech. Project Session (2012-13): Topic #2
Project Title: “Modeling of Piezoelectric (PZT) materials for actuation of various MEMS
structures.”
Supervisor: B. S. Panwar.
Objective:
(1) Modeling and simulation of PZT actuated catilevers and diaphragms for MEMS
based Resonators for force and mass sensing applications.
(2) Integration of these PZT MEMS structures with CMOS based differential amplifier.
Short description:
Microcantilevers, bridges and diaphragms are the most simplified and common MEMS
structures in the field of micromachined transducers. These MEMS structures are relatively
simple and inexpensive to fabricate and analytical solutions of their displacement profiles and
stress distributions under load are well developed. These structures are commonly used as
force and displacement sensors as well as mass sensors when excited in resonance. When
used in dynamic or resonance mode, these structures are mechanically deflected by different
actuation techniques, piezoelectric being most commonly used. Numerous microcantilever
devices have been implemented for ultra low mass sensing for biological and chemical
applications [1,2]. The motion of a cantilever beam can be sensitively monitored by means of
a variety of techniques, such as variations in piezoresistivity, piezoelectricity, capacitive
method, optical beam deflection and embedded transistor semiconductivity. This work will
also emphasize on the embedded MOSFET sensing technique. In order to reduce the number
of off-chip components required to operate a sensing system, more and more microelectronic
building blocks are integrated together with the microsensor on the same chip [3,4]. In this
project work we propose the integration of PZT actuated MEMS structures with a CMOS
based differential amplifer which will amplify only the difference signal of the sensing and
the reference sensors, and also minimizes systematic noise and environmental perturbations.
Use of embedded MOSFET sensing technique will further ease the integration of low power
CMOS electronics and MEMS structure.
References:
[1] Y. T. Yang, C. Callegari, X. L. Feng, K. L. Ekinci, and M. L. Roukes, “Zeptogram-Scale
Nanomechanical Mass Sensing,” Nano Lett., Vol. 6, No. 4, 2006.
[2] B. Ilic, and H. G. Craighead, “Attogram detection using nanoelectromechanical
oscillators,” J. Applied Physics Vol. 95, No. 7, 2004.
[3] G.K. Fedder, R.T. Howe, T.J.K. Liu, and E.P. Quevy, “Technologies for Cofabricating
MEMS and Electronics,” Proceedings of the IEEE, Vol. 96, No. 2, 2008.
[4] O. Brand, “Microsensor Integration Into Systems-on-Chip,” Proceedings of the IEEE,
Vol. 94, No. 6, June 2006.

3. M.Tech. Project Session (2012-13): Topic #3
Project Title: “Design Optimization of Piezoelectric Energy Harvester”
Supervisor: B. S. Panwar.
Objective: Virtualization of Piezoelectric Energy Harvester Design Using COMSOL,
MATLAB interface with Power Management Circuit
Project Summary
In the present work a comprehensive literature survey is to be completed and the issues
that need to be addressed to bring the MEMS based energy harvesting systems a viable
system for charging of wireless sensors nodes and cellular phones is to be examined. This
project will concentrate on the optimization of PZT micro-cantilever geometry to convert
the mechanical vibrations to electrical signal using Data Acquisition Toolbox for
connecting MATLAB to data acquisition hardware. This methodology requires interface
of PZT micro-cantilever design software with MATLAB which can be connected to the
power management circuit using the appropriate sampling rate data acquisition card. This
will facilitate conversion of simulated mechanical vibrations to an electrical signal, which
can be used to drive the power management circuit. There is large number of options for
ac/dc conversion architecture. The best architecture need to be identified analyzed and
interfaced with the virtual design philosophy using COMSOL and DATA acquisition
Tool Box of MATLAB. In this process a virtual design platform is to be formed which
interfaces the COMSOL design tools with the power management circuit using a data
acquisition card. A typical block diagram of such a configuration is shown below:
The definition and scope of work can be described as below:
1. Establishing the interface between the cantilever design tools COMSOL with
MATLAB using the Data Acquisition Tool box.
2. Identification and selection of proper sampling rate data acquisition card and
establishing its functionality with the personal computer or laptop.
3. Interface of the ac signal obtained from DAQ interfaced with Personal Computer and
analyzing the complete structure using the Simulink Design Tools.
4. Optimizing the geometry of the piezoelectric energy harvester to get the maxm. power
delivered to the battery for charging.

4. M.Tech. Project Session (2012-13): Topic #4
Project Title: “Design and Implementation of Wireless Body Area Network ”
Supervisor: B. S. Panwar.
Objective: Developing a patient monitoring system using body area network.
Project Summary
Design and implementation of a Wireless Body Area Network for health care
applications:
Patient monitoring in a hospital environment is becoming more and more complex with
multiple parameters (ECG, EEG, temperature, pressure, etc) to be measured and the need to
network the data gathered from many patients for observation at a central monitoring station.
The objective of present project is to design a wireless communication protocol for the
multiplexing of data gathered from multiple patients and to use a fiber optic link to collect the
multiplexed data streams and transmit them to the monitoring station for analysis and
interpretation
The work will involve selection and acquisition of biomedical sensors, development of
hardware for data processing and RF interface for wireless communications. Different
multiplexing approaches like TDMA, FDMA, CDMA, SDMA will be investigated and the
best one implemented. The multiplexed data streams will be collected together and fed to a
fiber optic communication link for data transmission to the sink node. MATLAB will be used
with an appropriate DAQ for data acquisition, display, monitoring and analysis.
This is hardware based project and efforts will be made to develop a prototype of the
proposed system and test it in a realistic environment.

5. M.Tech. Project Session (2012-13): Topic #5
Project Title: “SAW based wireless sensor Netwrok ”
Supervisor: B. S. Panwar.
Objective: Developing wirelessly interrogatable sensor network.
Project Summary
Development of a passive, wirelessly interrogable sensor network based on SAW
devices:
In harsh industrial environments like high temperature , pressure, radiation, moving machine
parts, etc, it is impossible to use conventional semiconductor based sensors with wired
connections. Sensors need to be embedded in structures like bridges and implanted in
patients for health care applications which requires battery less operation (for a long lifetime).
Surface Acoustic Wave technology provides us with a wide variety of passive, wirelessly
interrogable sensors, based on wide band delay lines and narrow band resonators, which are
able to operate satisfactorily in extremely harsh environments.
The objective of the present project will be to design and fabricate SAW sensors for detection
of temperature, pressure, gases, etc using delay lines and resonators. The reader electronics
will be developed to wirelessly interrogate the SAW sensors and extract information from
them. To increase the number of sensors in the network, multiple access schemes like TDMA,
FDMA, CDMA, SDMA will be studied and developed.
At the end of the project, we should have some SAW based sensors and electronics for
interrogating them. It should be possible to demonstrate the interrogation of multiple SAW
sensors using an appropriate multiple access scheme.

6. M.Tech. Project Session (2012-13): Topic #6
Project Title: “Evolving New Techniques of Recording Brain Waves and Telepathy a
Future Mode of Communication”
Supervisor: B. S. Panwar, and Dr. Puneet Agarwal- Senior Neurologist Max Hospital
Objective: Analysis of recorded brain waves for predicting mental disorder and proposing
brain waves a Future Mode of Communication”
Project Summary:
To record the brain waves with newer techniques in more comprehensive and sensitive
manner so that we can detect different neurological and even mental disorders (psychiatric) in
very early stage which will help in treatment as well as in prevention.
The project can be outlined as below:
1. A comprehensive survey on the tools and techniques of recording brain waves.
2. Analysis using standard signal processing tools for finding the deviations in the
recorded brain waves Delta, Theta, Alpha, Beta and Gamma for a normal and a
person having mental disorder.
3. Proposing new techniques of recording brain waves to record the electrode potential
in graded manner, recording ultrasounds accounting for movement of different parts
of the brain.
4. High speed digital recording of EEG signals for improved interpretation and
diagnostics.
5. Exploring telepathy as the future mode of communications.