Mj. Loboda et al., PLASMA-ENHANCED CHEMICAL-VAPOR-DEPOSITION OF A-SIC-H FILMS FROM ORGANOSILICON PRECURSORS, Journal of vacuum science & technology. A. Vacuum, surfaces, and films, 12(1), 1994, pp. 90-96
Citations number
27
Categorie Soggetti
Physics, Applied","Materials Science, Coatings & Films
A study of the growth of a-SiC:H films by plasma-enhanced chemical vap
or deposition (PECVD) from two organosilicon precursors, silacyclobuta
ne (H2CH2SiCH2CH2 or SCB) and methylsilane (CH3SiH3), is described. A
capacitively coupled, parallel plate PECVD system was used to grow fil
ms at 250 degrees C and deposition pressure of 2.0 Torr. Standard (13.
56 MHz) and low frequency (0.125 MHz) rf sources were used to generate
the deposition plasma. Depositions were performed with and without ar
gon dilution (neat) of the precursor. We report some of the first proc
ess/property relationships for organosilicon based a-SiC:H films grown
using st fixed, controlled set of de position conditions. included ar
e data on film composition, structure, dielectric constant and stress.
Films deposited from silacyclobutane had much higher carbon concentra
tions than those deposited from methylsilane, but in both cases the ca
rbon fraction in the film was lower than that in the precursor. It is
found that the plasma drive frequency has a stronger influence on film
composition than argon dilution of the precursor during deposition. T
he low frequency plasma significantly increases the film growth rate f
or the neat precursor process. Depending on the growth process, the re
lative dielectric constants of the a-SiC:H films ranged from 3.6 to 8.
7. The variation of the dielectric constant over the frequency range 0
.1-1000 kHz was negligible. Ah measured film stress was compressive an
d ranged from 0.1 to 1.0 GPa depending on precursor and plasma frequen
cy. Films deposited from a 10% organosilicon/90% argon mixture showed
higher dielectric constants, higher refractive indices and less bound
hydrogen when compared to neat organosilicon precursor depositions. Th
e films exhibited excellent oxidation resistance and could not be etch
ed in 6:1 buffered HF solutions. The properties of the a-SiC:H films a
re compared to PECVD hydrogenated silicon nitride and discussed in the
context of applications requiring low temperature deposited protectiv
e dielectric coatings.