Improved Optical Fiber Probes for Scanning Near Field Optical Microscopy
Date
2004-12
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
New York State College of Ceramics at Alfred University. Kazuo Inamori School of Engineering.
Abstract
The motivation behind this work stems from a combination of my interest in atomic
force microscopy (AFM) and the need to apply AFM to several areas of glass research.
AFM was used as the main characterization tool in the study of near-field scanning
optical microscopy (NSOM) tip formation, evaluation of phase separation in glasses and
copper oxide semiconductor film formation.
The use of atomic force microscopy (AFM) to evaluate the evolving tip structure
of an optical fiber probe for NSOM was studied. This study demonstrates the feasibility
of predicting the final tip cone angle, without taking the etching process to completion.
Cone angles reported in this study ranged from 58 to 152 degrees, depending on the fiber
type and etch conditions. The ability to vary the probe cone angle, and utilize AFM to
evaluate the cone angle that results from a set of etch conditions, are valuable additions to
the development of NSOM fiber tips.
The chemical and spatial variation of phase separated morphologies in glasses can
range from a few angstroms to microns, often requiring very high magnification for
detection. Historically phase separated glasses have been characterized by transmission
electron microscopy (TEM), a time consuming and costly technique. Atomic force
microscopy (AFM) provides an inexpensive alternative to TEM and has proven to be a
powerful tool in the evaluation of type, degree and scale of phase separation in glasses
down to the nanometer level.
AFM was used to show that the thickness and uniformity of the CuO films grown
in-situ on the surface of copper containing alkali borosilicate glasses increased with time
and temperature, however an upper time limit was reached in which no further thickness
increases were realized. Tenorite, cuprite and copper metal films were produced
depending on the heat treatment environment. XPS was utilized to confirm that copper
oxide film formation during heat treatments of glasses near Tg results from the oxidation
of copper ions, in the near surface region of the glass, from the 1+ to the 2+ state.
Description
Advisory committee members: Thomas Seward, William Lacourse, Matthew Hall. Dissertation completed in partial fulfillment of the requirements for the degree of Doctorate of Philosophy in Glass Science at the Kazuo Inamori School of Engineering, New York State College of Ceramics at Alfred University
Type
Thesis