MONOLAYER GRAFTING ON ELECTRONIC MATERIALS USING SUPERCRITICAL FLUID MEDIUM

Abstract

Organic monolayer functionalization is playing a key role in the development of many current and future technologies such as optoelectronic devices, highly-selective and sensitive sensors, studying biological and chemical interactions at the molecular level, and polymer synthesis. The deposition of highly stable and ordered monolayers has been identified as the basis of inorganic-organic hybrid devices which will ultimately pave the path for molecule-based devices and electronics. However, the currently prevailing organic solvent-based methods are incapable of depositing high- quality monolayers and thus pose a hindrance in realizing the full potential of monolayer functionalization.

In this thesis, supercritical CO2 (SCCO2) was used for deposition of highly stable and ordered monolayers. The advantageous gas-like transport properties, liquid-like solvation power and absence of surface tension of SCCO2, coupled with processing advantages of the herein developed reactor design were employed for two main objectives: 1) improve the monolayer quality of the molecules which cannot be reproducibly deposited by currently available organic solvent methods, 2) use the unique processing capabilities of SCCO2 to deposit novel monolayers. Furthermore, a completely new approach for monolayer deposition by SCCO2 was proposed toward the end of the thesis.