Spectroscopic study of gas and surface phase chemistries of CF4 plasmas in an inductively coupled modified gaseous electronics conference reactor

Autor: Baosuo Zhou, Eric A. Joseph, Lawrence J. Overzet, Matthew Goeckner
Rok vydání: 2006
Předmět:
Zdroj: Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films. 24:114-125
ISSN: 1520-8559
0734-2101
Popis: Gas and surface phase chemistries of CF4 plasma were studied in an inductively coupled modified gaseous electronics conference reference cell, using in situ Fourier transform infrared spectroscopy enhanced by a multipass White cell and in situ spectroscopic ellipsometry. The self-bias dc voltage, densities of gaseous species, fluorocarbon film thickness on Si substrate, as well as etch rates of SiO2 and Si were measured during plasma processing as functions of the pressure, CF4 gas flow rate, rf source power, platen bias power, and source-platen gap. The gaseous molecules and radicals monitored included CF4, CF3, CF2, SiF4, and COF2, among which CF4 and SiF4 were found to be the two dominant species, combining for about 80% of the total concentration. The density ratio of SiF4 and COF2 was about 2:1 with no bias on the substrate and increased up to ∼8:1 when Si substrate etching took place. Specifically, as the Si etch rate increased, the COF2 density dropped, likely due to suppressed etching of the quart...
Databáze: OpenAIRE