Welcome to 44X-2010-17 Senior Project - NanoWire Device Design
Mentor: Professor John F. Conley, Jr. -- Sponsor: ON Semiconductor
Thu May 23 22:16:09 2013
Left-to-right: Crystal Gupta, Dustin Austin, Akhila Nandgopal
Nanowire researchers are making a positive impact on the medical device industry. By creating very small sensors using nanowires, less invasive ways of testing can be developed. The development of a nanowire devices can be traced to two main processes; growing and harvesting the actual nanowires in such a manner that fits the application and then depositing the nanowires onto a semiconductor to create a basic electrical device, which can be done through the manipulation of several factors.
The project consists of two parts; initially the purpose of the project is to experimentally determine the best method for obtaining consistent nanowire lengths through filtration. Next, dielectrophoresis, which is the concept of force acting on a particle which is subjected to a non-uniform electric field , will be used to manipulate the orientation of the nanowires for ideal positioning and spacing. Zinc Oxide (ZnO) nanowires will potentially be grown using a seeding method. A ZnO seed will be placed into a growth chamber, and then ZnO powder will be used to grow the wire. Due to the inconsistent growth nature, it is vital to obtain wires that are consistent in size. If the lengths are different for each growth cycle, the properties of the device created by the wires will be different. Having inconsistent wire lengths will make the devices hard to classify and study. The plan is to improve on current methods by analyzing and modifying the methods currently used for wire length filtration. This involves running other processes in parallel to the newly developed process for filtration and determining which process allows for the best wire length distribution. The goal is to find an ideal distribution of wires that conform to one length within a given percentage of error.
For the second portion of the project, the plan is to use dielectrophoresis on the grown and filtered nanowires to find the best method for them to sit across a silicon channel. The silicon channel will have electrodes on either side and the nanowires will bridge the gap in an ideal position and spacing creating a field effect transistor (FET). Current methods of placement for nanowires result in the wires sitting in awkward directions and with inaccurate spacing along the silicon channel. These inaccuracies can lead to poor device functionality and poor electrical properties. The goal is to improve on the arrangement, quantity, and spacing of the nanowires by modulating the AC frequency, quantity of wires, substrate angle, and nanowire suspension solution.
- Gain background understanding of Research Topic
- Create and Share Notes on Background Articles
- Create a Trial of 3 Separate Wire Filtration Methods
- Implement Most Favorable Filtration Method
- Determine Capture Radius of Substrate
- Determine Optimum Frequency for Consistent Wire Spacing
- Determine Voltage at which Nanowires Release from Electrodes
- Manipulate Number of Wires in Suspension Solution
- Experiment with Various Suspension Fluids
5.1 Flow Chamber, Etch Channel, Deposit Channel Electrodes
5.2 Electrode Filtration Chamber
5.3 DEP Filtration Method
5.4 SEM for Filtration
5.5 Electrode Spacing Setup
5.6 DEP Spacing Method
5.7 SEM for Spacing
5.8 Device Characterization
No longer Available.
10 Group members
 H. A. Pohl, Dielectrophoresis: The Behavior of Neutral Matter in Nonuniform Electric Fields. Cambridge: Cambridge University Press, 1978.
The 44x-2010-17 Team - The Nano Naughts