Date of Award
Bachelor of Science (BS)
Chemistry and Biochemistry
Dr. Alison Noble
The electrooptical properties of zinc selenide (ZnSe), a semiconductor transparent in the infrared region of the electromagnetic spectrum, have been exploited in the development of a variety of scientific technologies. Previous studies have demonstrated the facility of this substrate for the adsorption of alkanethiol self-assembled monolayers (SAMs) and the supporting of nematic liquid crystals (LCs), such as 4-cyano-4’- pentylbiphenyl (5CB). We have investigated the influence of the ZnSe surface morphology on the electrooptical dynamics of ultra-thin 5CB liquid crystalline films supported on both the bare substrate and a surface functionalized with hexadecanethiol (HDT) SAMs. Infrared spectra indicate that the introduction of an HDT monolayer between the ZnSe surface and the liquid crystalline film reorients the average director of the film with respect to those supported on bare ZnSe. Furthermore, the attenuation of the electronic effects of the ZnSe surface by the SAM led to a notable decrease in the 1 threshold voltage required to induce the Fréedericksz transition in the 5CB film. This feature of the HDT funcationalized ZnSe suggests the possibility of fine-tuning the dynamics of 5CB, allowing for additional applications of the substrate. In conjunction with this study, we report a new bi-layer positive resist methodology for the fabrication of a gold interdigitated electrode microarray on ZnSe—a methodology that can be readily generalized for the fabrication of other microscale structures on ZnSe.
Rossomme, Elliot C.; Tay, Nicholas; and Noble, Alison, "Electrooptical dynamics of ultra-thin nematic liquid crystalline films supported on ZnSe functionalized with alkanethiol self-assembled monolayers" (2017). Honors Projects and Presentations: Undergraduate. 21.