RUI: Acquisition of an X-ray Photoelectron Spectroscopy System for Materials Science Research and Undergraduate Education

University Of Wisconsin-Eau Claire, Eau Claire WI

Investigators

Abstract

This award from the Major Research Instrumentation program and the Instrumentation for Materials Research Program to the University of Wisconsin-Eau Claire provides partial support for the acquisition of a x-ray photoelectron spectroscopy system for research and undergraduate education and training. The instrument will be used to investigate the physics and chemistry of semiconductors, thin films, and metallic alloys. Several different systems will be studied. These include: 1) the electronic, chemical, and structural properties of compound IV-IV semiconductors, including the passivation, oxidation, oxynitridation and metallization; 2) the chemistry of the molecular precursors typically used in gallium-nitride and indium-gallium-nitride film growth, as well as the chemistry of the molecular fragments from such precursors; 3) the growth mechanisms and structures of thin metal films on semiconductors; and 4) corrosion processes of metal alloys and thin films. Since undergraduate research is a critical component of the educational system at the University of Wisconsin-Eau Claire, students will perform research with the new instrument. It will be used in course work and will be used to educate and train students in materials research. This award from the Major Research Instrumentation program and the Instrumentation for Materials Research Program to the University of Wisconsin-Eau Claire provides partial support for the acquisition of an x-ray photoelectron spectroscopy (XPS) system for research and undergraduate education and training. Semiconductors, metals, and insulators are the materials that make microelectronic chips possible. Nearly all computer chips, for example, are fabricated from silicon. Similar materials and used in electro-optic devices, such as light-emitting diodes used in many consumer electronics and increasingly in the automotive industry and roadway signing, and diode lasers, which form the heart of laser printers and compact disc players. The successful fabrication of computer chip and electro-optic devices requires a detailed understanding of the physics and chemistry of the interface between two materials, as well as fundamental processes occurring on the surface of these materials. Surface properties and composition are therefore important to the fabrication of useful devices. X-ray photoelectron spectroscopy (XPS) is a technique that provides information about surface composition and is capable of providing information about the "chemical state" in which surface atoms exist. The instrument will be used to: 1) investigate semiconductor and metal surfaces, and how varying surface composition of either material influences the interface that forms between two dissimilar materials; 2) follow surface chemical reactions relevant to growing thin films of materials and how etching reactions proceed at semiconductor and metal surfaces; and 3) study how surface composition influences surface structure and morphology during film growth and etching. Undergraduate students, including students from physical sciences as well as life sciences, will be involved in all research projects and will operate and help to maintain the new instrument as part of their collaborative research projects with faculty research mentors.