SIR Physics Investigation Abstract
CHARACTERIZATION OF THIN ALUMINUM OXIDE FILMS DEPOSITED USING ATOMIC LAYER CHEMICAL VAPOR DEPOSITION (ALCVD)
Presenter:
Hon Lung Chu, Illinois Mathematics and Science Academy
Advisors:
Mr. Manish Singh, University of Illinois at Chicago
Dr. Christos Takoudis, University of Illinois at Chicago
Abstract:
Current Complementary Metal-Oxide Semiconductors (CMOS) are experiencing excessive heat and high power consumption due to over-scaling of the SiO2 dielectric layer. In this research, the potential of aluminum oxide (Al2O3) as a replacement gate material was studied. The characteristics for the ideal material are - abrupt interface with silicon, amorphous structure, and thermal stability at high temperatures, so as to ensure its compatibility with the existing semiconductor device fabrication technology. Thin aluminum oxide films, deposited using Tri-Methyl Aluminum (TMA) and oxygen, have been characterized. The film composition and thermal stability were studied using Fourier Transform Infra-Red (FT-IR) spectroscopy, X-ray Photoelectron Spectroscopy (XPS) and ellipsometry. FT-IR and XPS analysis of the as-deposited film indicated presence of aluminum oxide without the interfacial silicon oxide layer. To study its thermal stability, the film was annealed in argon ambient in furnace at temperatures up to 1000°C. An increase in the film thickness due to formation of silicon oxide at interface was observed. To investigate the source of oxygen, clean silicon wafers were heated at the same conditions. Formation of silicon oxide was still observed which may suggest that the silicon oxide formation might have been the result of oxygen in the annealing atmosphere.