Low-temperature plasma-enhanced chemical vapor deposition of silicon oxide films and fluorinated silicon oxide films using disilane as a silicon precursor

摘要

High-quality SiO.sub.2 films may be deposited at low temperatures by plasma-enhanced chemical vapor deposition using disilane (Si.sub.2 H.sub. 6) and nitrous oxide (N.sub.2 O) as silicon and oxygen precursors in an otherwise conventional reactor such as a parallel plate plasma reactor. The properties of the SiO.sub.2 films deposited at 120 C. using Si.sub.2 H.sub.6 and N.sub.2 O were not significantly different from those of conventional SiH.sub.4 -based SiO.sub.2 films deposited at the significantly higher temperature range 250-350 C. PECVD deposition of SiO.sub.2 films using Si.sub.2 H.sub.6 and N.sub.2 O provides a practical low temperature process for fabricating microdevices and circuits. This low temperature process can be used for deposition in the presence of polymers, semiconductors, and other components that would melt, decompose, or otherwise be sensitive to higher temperatures. Fluorinated silicon oxide may also be deposited at the relatively low temperature of 120 C. with plasma-enhanced chemical vapor deposition using CF.sub.4 as a fluorine source in the deposition process from Si.sub.2 H.sub.6 and N.sub.2 O. The incorporation of fluorine maintains the physical properties of the films, while improving their electrical properties, such as reducing failures due to early dielectric breakdowns, enhancing performance as an insulator, and reducing the presence of unwanted electrical charges.