Tilte: "FABRICATION AND CHARACTERIZATION OF SUB-MICROMETRIC SILVER STRUCTURES BY SELF-ASSEMBLY AND LASER INTERFERENCE LITHOGRAPHY"
Author: NOEMÍ PÉREZ HERNÁNDEZ
Date: 2008-11-14
Director: Dr. Santiago Miguel Olaizola Izquierdo
Abstract:
The present work studies the fabrication of metallic photonic structures with potential photonic applications using cost-effective fabrication techniques.
Two techniques have been evaluated: self-assembly of colloidal spheres and laser interference lithography.
In this work, the self-assembly technique consists of three different steps which are studied and optimized in the present study. The first one is the optimization of the deposition conditions of transparent conductive indium tin oxide thin films which will be used as the working electrode in subsequent process steps. Both low resistance and high transmittance are obtained in sputtered indium tin oxide thin films. The second step is the assembly of colloidal spheres for the formation of artificial opals. A phenomenological study of the influence of different parameters such as temperature, relative humidity, concentration, deposition angle or solvent on the final order of the artificial opals is carried out. The third step is the infiltration of the opals with the desired material, silver in this case, which is performed by electrochemical means. The last step is the inversion of the opals, giving rise to ordered sub-micrometric silver structures.
The laser interference lithography technique is used for the fabrication of sub-micrometric silver structures using two different approaches: reactive ion etching and lift-off.
The silver structures fabricated by both techniques are structurally and optically characterized. It is demonstrated in this work that these structures present optical properties which make them feasible for future photonic applications.
