Production and characterization of nanometer diameter clusters and cluster-based thin films
Abstract
This research work is an effort to synthesize novel metal and metal oxide clusters in a multiple expansion cluster source (MECS) and to explore the unique properties of nanometer diameter clusters and cluster based thin films. The MECS is an aerosol reactor, which operates by quenching hot metal vapor by mixing it with cold inert gas. It was used to produce clusters of gold, silver, aluminum, aluminum oxide and iron with diameters in the nanometer size range. Optimum operating conditions for each system were established in terms of reactor configuration, oven temperature and inert gas flow. The cluster aerosol produced in the MECS is expanded through a capillary into a vacuum chamber to form a cluster beam, and the clusters are soft-landed on various substrates. TEM, SEM, STM, SFM and XRD were used to characterize individual supported clusters and study thin films produced by cluster beam deposition (CBD). Electrical resistivity measurements were also used to study electron transport in gold CBD films, and image analysis techniques are utilized to study the initial growth of gold and silver CBD films. Several applications of supported metal clusters and CBD films were explored. Thin film applications include formation of gold mirrors and metallization of semiconductor vias. Applications of supported clusters include standards for SFM tip calibration, cluster coating of commercial SFM tips, and AFM studies of the forces between clusters and substrates.
Degree
Ph.D.
Advisors
Andres, Purdue University.
Subject Area
Chemical engineering
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.