Unconventional Approaches to Structured Semiconductors

Citation

Thompson, Jonathan Ross (2019) Unconventional Approaches to Structured Semiconductors. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/YW6M-H367. https://resolver.caltech.edu/CaltechTHESIS:07272018-145200158

Abstract

The function of semiconductor devices is intrinsically tied to their structure. While there are already myriad techniques in use today to fabricate an extreme diversity of devices, new processes are regularly developed to make the production of previously unrealizable structures, and consequently devices, possible.

This dissertation deals with several unconventional approaches to generating ordered semiconductor structures. One chapter discusses a novel technique to measure the various forces that impede the alignment of randomly dispersed microstructures. The technique made it possible to both determine the magnitude of the interactions that the particles must overcome in order to be organized into a useful structure and assess the functional form of the forces that the microstructure is experiencing, thereby giving insight into the physical origin of said forces.

The following chapter deal with the spontaneous structure formation seen in photoelectrodeposited semiconductor films. One chapter investigates how the natural tendency of these films to form oriented, high aspect ratio structures can be coupled to the geometry of the substrate on which they are grown. This work demonstrates that extremely straight, high aspect ratio structures can be grown over macroscopic areas by making simple modifications of the substrate.

The final chapter characterizes the iridescence that these films exhibit. A simple physical explanation for the origin of the coloration is posited and verified. Then the information gleaned about the optical response of these films is used to generate vibrant, colorful patterns on electrode using consumer electronics.

Thesis Files