This Small Business Innovation Research Phase I project involves the development of a cost effective, scaleable, and non-lithographic-based deposition system to deposit electrically conductive CNTs patterns on a wide range of substrates. The advantageous physical properties of carbon nanotubes (CNTs), including excellent electrical, thermal conductivity, good mechanical strength, semiconducting/metallic nature, and advanced field-emission behavior, have been utilized in various different devices. The area-selective synthesis or deposition of CNTs on pre-patterned growth templates using either catalytic or plasma-enhanced chemical vapor deposition methods opens up further fields for advanced future applications. However, these techniques require complex lithography processes and sophisticated deposition facilities or are limited to thermally durable growth substrates. Lynntech and their collaborators will develop an innovative digital optical chemistry processor (DOC-P) to create a reactive surface for the subsequent assembly of CNTs through electrostatic or covalent interactions. The DOC-P involves focusing UV-light onto surface-treated substrates by reflection from an independently controllable micron-sized polished micromirror array commercialized by Texas Instruments eliminating the need for photo-masks. The technology will allow more rapid deposition than inkjet-printing or DipPen approaches. In Phase I, electrical behavior, adhesion strength, and optical transparency of the printed patterns will be investigated and limitations of the process will be determined.
The proposed system provides a simple and rapid method to generate transparent conductive patterns using carbon nanotubes. Successful patterning of CNTs using DOC-P will lead to reduction in manufacturing costs. The technology can be used to make electronic circuits and field emission displays on highly transparent conductive films. According to Nanomarkets LC, a company specialized in analyzes nanotechnology market, while some of the circuits for flexible plastic displays can use CNTs, the biggest opportunity for CNTs in the display sector will come from field emission displays (FEDS) which may provide the first mass market for CNTs. Nanomarkets LC expects FEDS will generate more than $700 million in revenues by 2009. The properties and processing advantages of DOC-P technology will also find uses in commercial applications such as touch screens, larger areas displays, flexible display and solar photovoltaic collectors. The DOC-P setup allows the fabrication of different conductive patterns without the use of high cost photo-mask procedures, making it very useful for educational research laboratories. The process to make such patterns or circuits is also very environmental friendly as photoresists or toxic solvents are not needed for patterning or the immobilization of CNTs.
