Chemical Vapor Etching of Copper Using Oxygen and Various Beta-Diketones

A vertical-flow warm walled reactor was constructed to investigate the reactions of oxygen and beta-diketones on copper metal. The etch rate was studied as a function of time, temperature, grain orientation, oxygen partial pressure, beta-diketone, and beta-diketone partial pressure. Studies were performed at total pressures ranging from 10 to 200 Torr and substrate temperatures of 250 to 400°C. Copper disks, 9 mm in diameter, as well as thin evaporated films were used as substrates. The production of the corresponding Cu(II) beta-diketone was confirmed by trapping the products down stream of the reactor and analyzing them using gas chromatography/mass spectroscopy. Etch rates over 1.5 mum/min were achieved at substrate temperature of 350°C using 200 Torr of O 2 and 50 Torr of hexafluoropentanedione. The degree of surface contamination was found to be a functions of the O2/hfacH ratio and temperature. At low O2/hfacH ratios the etching took place cleanly while high O2/hfacH ratios produced a thick oxide film The activation energy for etching at high O2/beta-diketone was found to decrease with decreasing sublimation temperature for the corresponding metal chelate. Finally, the decomposition of hfacH was found to be negligible when using a copper substrate while Ni, 316 SS, and Pt catalyst powder showed significant hfacH decomposition.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Steger, Richard Mero

Contributors dc:contributor

• Masel, R.I.

• Engineering, Chemical

Language dc:language

eng

Identifier

(MiAaPQ)AAI9912387

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/82462