Ion-bombardment-enhanced plasma etching of tungsten with NF/sub 3//O/sub 2/

Journal Article · Thu Sep 01 00:00:00 EDT 1988 · J. Vac. Sci. Technol., B; (United States)

DOI:https://doi.org/10.1116/1.584216· OSTI ID:6791137

Greene, W M; Hess, D W; Oldham, W G

Ions and neutrals sampled from a NF/sub 3//O/sub 2/ etching plasma were observed by a quadrupole mass spectrometer and cylindrical mirror ion energy analyzer to investigate ion-bombardment-enhanced etching of tungsten. Dc biasing of a 13.56 MHz, 2.7 Pa, 1.24 W/cm/sup 2/ , 3/1 NF/sub 3//O/sub 2/ glow discharge raised the average ion energy bombarding the grounded electrode from 35 to 172 eV concurrent with an increase in the ion current by a factor of 3. Total conversion of NF/sub 3/ to N/sub 2/ and F/sub 2/ occurred under these conditions yielding a typical etch rate of polycrystalline tungsten of 150 nm/min. The primary ion observed was WF/sup +//sub 5/. The WF/sub 6/ etch product concentration was independent of ion energy, but correlated strongly with ion current. The results support a damage-induced chemical reaction as the enhancement mechanism.

• Research Organization: Department of Chemical Engineering, University of California, Berkeley, California 94720
• OSTI ID: 6791137
• Journal Information: J. Vac. Sci. Technol., B; (United States), Vol. 6:5
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
36 MATERIALS SCIENCE
MOLECULAR IONS
COLLISIONS
TUNGSTEN
ETCHING
ION COLLISIONS
MOLECULE COLLISIONS
TUNGSTEN FLUORIDES
ELECTRODES
GLOW DISCHARGES
PHYSICAL RADIATION EFFECTS
CHARGED PARTICLES
ELECTRIC DISCHARGES
ELEMENTS
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
IONS
METALS
RADIATION EFFECTS
REFRACTORY METAL COMPOUNDS
SURFACE FINISHING
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TUNGSTEN COMPOUNDS
656003* - Condensed Matter Physics- Interactions between Beams & Condensed Matter- (1987-)
360101 - Metals & Alloys- Preparation & Fabrication