I was selected as an exchange student in the final year of my degree to University of California, Davis, CA under Global Study Program. I completed my B.Tech final Thesis there. I enrolled for Fall’08 and Winter’09 and continued my research work along with course work with subjects from Physics, Material Science (Graduate level) and Electrical and Computer Engineering.
I worked in Northern California Nanotechnology Center for Fall’08 and gained experience in micro and nano fabrication techniques from the month of September to December. My research was mainly concentrated on creating high aspect structures using SU8. Later the fabricated structures are used as a stamp for soft-lithographic process for PDMS Embossing. The different parameters such as spread and spin time, post exposure bake (PEB) and hard bake time and temperature are varied for a more stable structure. The purpose of the work was to have a closer look of various process steps of micro fabrication and have an experience in handling different equipments such as Karl-Suss MA4, a mask aligner and different spinners for coating the photoresists and pattern generator for mask fabrication with the use of L-Edit.
In the Fall quarter of 2008, as a part of the course Electromagnetic Radiation and Antenna, I designed a Patch Antenna. Before implementing it in the hardware, the characteristics of the Antenna were simulated using CST Simulator. The details of the actual readings and the simulated reading can be found here.
Later in Winter’09 I was accepted in the research group of Prof. Charles E. Hunt and started my research in Vacuum Microelectronics. I got 4 credits for the research as it was an Undergraduate Research course named as “Independent Study for advance Undergraduate”. My research was based on the field emission activity of RVC. The name of the thesis was “Field Emission Characteristics of Ion Irradiated Reticulated Vitreous Carbon”. The research was done to find out the field emission enhancement of RVC due to surface modification by bombarding it with Ar ions with an application of a grid. The research work proved the surface treated RVC has a better field emission current and beam characteristics as compared to other field emission cathodes. This work was submitted in partial fulfillment of the requirements for the award of the degree of B.Tech in SRM University. The total duration of the work was from January 13 to March 26 in UC Davis and from April 1 to May 12, which was the date for thesis defense, in SRM University. My project guide in SRM University was Prof. P. Arunapriya.
My research work in the 2nd & 3rd year of B.tech was mainly concentrated in the area of embedded systems, designing and simulations. Mainly implementation of logic gates in FPGA’s. The certification course in Altera Quartus-II was mainly to promote the software package Quartus-II and the Nios processor. This is also a famous CPLD (Complex Programmable Logic Device). I completed the course work with an S grade (that is 10 out of 10) having a project work in parallel processing of unsigned bits. I did a small project on HCS 08 micro controller too.
I published a paper describing an architecture of an embedded system having different parallel authentication systems.
I concentrated in the field of molecular electronics in my 3rd year. The main research work was to study the electron transport in different molecules. The transport was studied by the method of non Self Consistent Field (non-SCF). The simulations were done in the Huckle-IV package. The research work was primarily for a thorough understanding of molecular electronics. For the stated research I used to work with Dr. P. Aruna Priya, Asst. Prof. , SRM University.
Molecular electronics is a bottom-up approach in the nanotechnology field. It can be defined as the use of single molecular device or a molecular wire to perform signal and information processing.
The research work is done to analyze the characteristics of several molecules by means of simulation. The Non-Equilibrium Green’s Function (NEGF) formalism and density function theory (DFT) are used as the basis. Huckel-IV and MATLAB simulation software are used for the simulation and analysis of transmission characteristics, I-V and G-V characteristics. These characteristics are studied and the conduction capabilities of the molecules are analyzed.
To perform the simulation correctly the coordinate file of the molecule has to be oriented in a specific manner. The molecule has to be oriented in such a way that the line connecting the two end atoms (to which the gold atoms will be connected) should lie parallel to Y-axis. The end atom for which the Y vale will be smaller will be called the left end atom and the other end atom will be called the right end atom. The following figure will explain it correctly.
The Thiol group (-SH) gets replaced by the Au atom when connected to the gold pads. Pad distance is the vertical distance between the end atom and the Au pads, which is 1.905 Angstrom by default (S-Au is 2.53 Angstrom). The Au-Au is 2.885 Angstrom and the end atom is equidistant from the three gold atoms. The pad is connected in such a way that all the Au atoms are in XY-Plane as shown in the figure.