Recouping etch rates in pulsed inductively coupled plasmas

Journal Article · Sat Jan 15 04:00:00 EST 2011 · Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films

DOI:https://doi.org/10.1116/1.3521315· OSTI ID:22051165

Agarwal, Ankur; Stout, Phillip J; Banna, Samer; Rauf, Shahid; Collins, Ken ^[1]

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1. Applied Materials Inc., 974 E. Arques Avenue, M/S 81312, Sunnyvale, California 94085 (United States)

Pulsed rf plasmas are increasingly being employed for plasma etching at future technological nodes. Although the plasma uniformity usually improves with pulsing, the lower time-averaged power decreases the etch rate and the lower throughput is undesirable. It is therefore important to evaluate different strategies to restore higher etch rates while retaining the advantages of pulsed plasmas. In this work, the impact of varying pulsing modes in an inductively coupled plasma on plasma characteristics and feature profile evolution are discussed using the results from a two-dimensional reactor scale plasma model coupled to a Monte Carlo based feature profile model. Results are discussed for poly-Si etching in an Ar/Cl{sub 2} gas mixture. The consequences of source-only and bias-only pulsing modes on discharge characteristics, ion energy distributions (IEDs) to the wafer, and feature profile evolution are discussed. Although the etch depth rates were found to be higher for source-only pulsing compared to the synchronized (source and bias) pulsing mode, the higher ion energies in the afterglow period during source-only pulsing may also increase ion bombardment damage. Compensation of power may allow for increased etch depth rates while retaining the benefits of synchronized pulsing. Further, power compensation level can be varied to achieve fine tuning of the IEDs to the wafer.

• OSTI ID: 22051165
• Journal Information: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films, Journal Name: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films Journal Issue: 1 Vol. 29; ISSN 1553-1813
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AFTERGLOW
BEAM-PLASMA SYSTEMS
CHLORINE
DEPTH
ENERGY SPECTRA
ETCHING
ION BEAMS
MONTE CARLO METHOD
PLASMA
SPUTTERING
TWO-DIMENSIONAL CALCULATIONS