Location

Salt Lake Community College

Start Date

5-8-2006 10:30 AM

Description

The extreme ultraviolet (EUV) spectrum is becoming increasingly important. Its most promising applications include lithography for integrated circuits, space-based astronomy, and medical microscopes. Unfortunately, the optical constants of materials, particularly heavy metals, in this range are not well known. This work examines the molecular composition and oxidation rate and depth of thorium. Most of our data is collected through the use of X-ray Photoelectron Spectroscopy (XPS). XPS utilizes the photoelectric effect to obtain data about the exact composition of our material. X-rays are directed at the surface in question, colliding with and dispelling electrons from different energy levels of atoms. By measuring the number of electrons dispelled and their energies, the presence and quantities of elements can be determined. Depth profiling is done to examine the deeper layers of the sample, in which layers are etched off and new data is obtained. The results are then compared with existing literature. These methods are used to determine what chemical bonding occurs on the surface, whether or not it is diffused into lower layers, over what amount of time, and how the chemical composition varies with depth.

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May 8th, 10:30 AM

X-Ray Photoelectron Spectroscopy to Examine Molecular Composition

Salt Lake Community College

The extreme ultraviolet (EUV) spectrum is becoming increasingly important. Its most promising applications include lithography for integrated circuits, space-based astronomy, and medical microscopes. Unfortunately, the optical constants of materials, particularly heavy metals, in this range are not well known. This work examines the molecular composition and oxidation rate and depth of thorium. Most of our data is collected through the use of X-ray Photoelectron Spectroscopy (XPS). XPS utilizes the photoelectric effect to obtain data about the exact composition of our material. X-rays are directed at the surface in question, colliding with and dispelling electrons from different energy levels of atoms. By measuring the number of electrons dispelled and their energies, the presence and quantities of elements can be determined. Depth profiling is done to examine the deeper layers of the sample, in which layers are etched off and new data is obtained. The results are then compared with existing literature. These methods are used to determine what chemical bonding occurs on the surface, whether or not it is diffused into lower layers, over what amount of time, and how the chemical composition varies with depth.