Effect of simultaneous source and bias pulsing in inductively coupled plasma etching

Journal Article · Sun Nov 15 04:00:00 EST 2009 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3262616· OSTI ID:21361921

Agarwal, Ankur; Stout, Phillip J; Banna, Samer; Rauf, Shahid; Collins, Ken ^[1]; Tokashiki, Ken; Lee, Jeong-Yun ^[2]

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1. Applied Materials Inc., 974 E. Arques Avenue, M/S 81517, Sunnyvale, California 94085 (United States)
2. Samsung Electronics, Hwasung City, Kyunggi-Do 445-701 (Korea, Republic of)

Pulsed rf plasmas show promise to overcome challenges for plasma etching at future technological nodes. In pulsed plasmas, it is important to characterize the transient phenomena to optimize plasma processing of materials. In particular, it is important to evaluate the effect of the ion energy and angular distribution (IEAD) functions during pulsing on etching of nanoscale features. In this work, the impact of simultaneous pulsing of both source and bias in an inductively coupled plasma on plasma characteristics and feature profile evolution is discussed using results from a two-dimensional reactor scale plasma model coupled to a Monte Carlo based feature profile model. Results are discussed for an Ar/Cl{sub 2} gas mixture which is typically used for poly-Si etching. The consequences of duty cycle, pulse shape, and the phase lag between source and bias power pulses on discharge characteristics, IEADs to the wafer, and feature profile evolution are discussed. The low plasma density during the initial period of the pulse was found to introduce a high energy tail component to the IEADs. This high energy tail component can be affected by modifying the pulse shape. The Si etching rate is found to increase with increasing duty cycle but is lower compared to continuous mode of operation due to lower time averaged power deposition. Pulsing the source and bias out of phase provides for increased ion energies and fluxes to the wafer for a given duty cycle.

• OSTI ID: 21361921
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 10 Vol. 106; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ANGULAR DISTRIBUTION
CALCULATION METHODS
CHLORINE
DEPOSITION
DISTRIBUTION
ELECTRONIC CIRCUITS
ELEMENTS
ETCHING
EVOLUTION
HALOGENS
MATERIALS
MONTE CARLO METHOD
NANOSTRUCTURES
NONMETALS
PLASMA
PLASMA DENSITY
PULSE CIRCUITS
PULSE SHAPERS
PULSES
SEMICONDUCTOR MATERIALS
SEMIMETALS
SIGNAL CONDITIONERS
SILICON
SPUTTERING
SURFACE FINISHING
TWO-DIMENSIONAL CALCULATIONS