Nano-Memristors as Bio-Detectors: Modeling and Validation

***Archived: This is a past project,  it is not on offer at the moment!***

Introduction and Description
Going down to the nano-scale, things change drastically.  With the realization of the first memristor by HP labs, a new era dawns upon man. The applications seem infinite. For even a fraction of the possibilities to be realized, it is of utmost importance to carefully understand and study the behavior of such devices.

Memristors are devices that maintain states and thus memory. However, they are passive devices and do not dissipate energy. The current-voltage characteristics are pinched hysteresis curves. With careful study of the characteristic curves of clean samples of Silicon Nanowires we realize that they demonstrate memristive behavior. However, it has been noticed that physical factors such as geometry, temperature and humidity have effects on the characteristic curves. These curves are asymmetric about the origin and unlike the perfectly symmetric Lissajous figures obtained in the HP Labs initial memristor.

An interesting observation, relevant to nanobiosensing is that Immunoglobulin-G functionalized nanowires show non-passive behavior. These samples show a separation in current minimas on a log-absolute current – voltage plot. More importantly, these samples show the remarkable ability to detect antigens. The antigen-antibody interactions reduce the minima gap based upon the concentration of antigen present in the close vicinity of the functionalized device.

The MASTER Project:
As part of this master project, we attempt to study the memristive effect in silicon nanowire devices with lengths ranging from 1 μm to 15 μm and diameters ranging from 50nm up to 190nm.

The goal is to understand the characteristic curves of functionalized Si-NW samples and their interaction with antibodies along with their dependence on physical parameters via modeling and simulation.

Tasks Involved:

Measurement of I-V Curves from various nanowire samples with different lengths and cross sectional areas

This project was supervised by David Sacchetto and Sandro Carrara.


***Archived: This is a past project,  it is not on offer at the moment!***