Ion effects on CF{sub 2} surface interactions during C{sub 3}F{sub 8} and C{sub 4}F{sub 8} plasma processing of Si

Journal Article · Wed Sep 01 04:00:00 EDT 2004 · Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films

DOI:https://doi.org/10.1116/1.1781180· OSTI ID:20636581

Martin, Ina T; Fisher, Ellen R ^[1]

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1. Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872 (United States)

Surface interactions of difluorocarbene (CF{sub 2}) molecules were investigated using our LIF based imaging of radicals interacting with surfaces (IRIS) apparatus. LIF data of CF{sub 2} in C{sub 3}F{sub 8} and C{sub 4}F{sub 8} plasma molecular beams reveal that the relative densities of CF{sub 2} increase with increasing rf power and source pressure in both plasma systems. The surface reactivity of CF{sub 2} molecules during C{sub 3}F{sub 8} and C{sub 4}F{sub 8} plasma processing of room temperature Si substrates was also measured over a broad rf power range and at different pressures. A scatter coefficient (S) greater than one was measured for all unperturbed systems, indicating that CF{sub 2} molecules are produced at the substrate surface during film deposition. The same systems were also studied under ion-limited conditions, yielding S{approx}1, clear indication that ions are partially responsible for CF{sub 2} surface production. Plasma ions were identified using plasma-ion mass spectrometry. These data indicate that higher levels of C{sub x}F{sub y}{sup +} (x>1) are produced in the C{sub 4}F{sub 8} plasmas. X-ray photoelectron spectroscopy analyses of treated substrates showed that amorphous fluorocarbon films were deposited during plasma processing of the substrates. A positive correlation was found between S(CF{sub 2}) and film composition of FC materials deposited in both the IRIS apparatus and independent reactors.

• OSTI ID: 20636581
• Journal Information: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films, Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films Journal Issue: 5 Vol. 22; ISSN 0734-2101; ISSN JVTAD6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CARBON FLUORIDES
DEPOSITION
ION BEAMS
LITHIUM FLUORIDES
MASS SPECTROSCOPY
MOLECULAR BEAMS
PLASMA
SILICON
SURFACES
TEMPERATURE RANGE 0273-0400 K
THIN FILMS
X-RAY PHOTOELECTRON SPECTROSCOPY