High Resolution Core-Level Photoemission Spectroscopy of Semiconductor- Oxide and Metal-Metal Interfaces

摘要

The focus of this project is the characterization of two types of interfaces of technological importance: SiO2/Si interfaces relevant to ultra thin gate oxides used for next-generation semiconductor electronics, and bimetallic interfaces (ultra thin films of metals on other metals) that have potential catalytic applications. The main tool is high resolution soft x-ray photoemission spectroscopy (SXPS) using synchrotron radiation at the National Synchrotron Light Source (NSLS). Device-grade films of silicon dioxide and silicon nitride have been grown on Si substrates and new insights into the control of interface electronic state density are found. In addition, SXPS has provided new results on the stability of transition metal films on tungsten substrates: monolayers of Pt, Pd, Ir, Rh are thermally stable, but multilayer films of the same metals form surface alloys.