450 mm dual frequency capacitively coupled plasma sources: Conventional, graded, and segmented electrodes

Journal Article · Wed Dec 01 00:00:00 EST 2010 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3517104· OSTI ID:21537956

Yang, Yang ^[1]; Kushner, Mark J ^[2]

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1. Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States)
2. Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, Michigan 48109-2122 (United States)

Wafer diameters for microelectronics fabrication will soon transition from 300 to 450 mm at a time when excitation frequencies for capacitively coupled plasmas (CCPs) are increasing to 200 MHz or higher. Already for 300 mm tools, there is evidence that wave behavior (i.e., propagation, constructive, and destructive interference) affects the uniformity of processing. The increase in diameter to 450 mm is likely to exacerbate these effects, perhaps requiring nontraditional tool designs. This is particularly important in dual frequency (DF) CCP tools in which there are potential interactions between frequencies. In this paper, results from a two-dimensional computational investigation of Ar plasma properties in a 450 mm DF-CCP reactor, incorporating a full-wave solution of Maxwell's equations, are discussed. As in 300 mm DF-CCP reactors, the electron density collapses toward the center of the reactor with increasing high frequency (HF), however, with more pronounced finite wavelength effects. Graded conductivity electrodes with multilayer of dielectrics are computationally demonstrated as a possible means to suppress wave effects thereby increasing plasma uniformity. Segmentation of the HF electrode also improves the plasma uniformity by making the electrical distance between the feeds and the sheath edges as uniform as possible.

• OSTI ID: 21537956
• Journal Information: Journal of Applied Physics, Vol. 108, Issue 11; Other Information: DOI: 10.1063/1.3517104; (c) 2010 American Institute of Physics; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ARGON
BOUNDARY LAYERS
DESIGN
DIELECTRIC MATERIALS
ELECTRODES
ELECTRON DENSITY
EXCITATION
EXPLORATION
INTERACTIONS
INTERFERENCE
MAXWELL EQUATIONS
MHZ RANGE
PLASMA
PLASMA DENSITY
REGULATIONS
RESOLUTION
SPUTTERING
WAVELENGTHS
DIFFERENTIAL EQUATIONS
ELEMENTS
ENERGY-LEVEL TRANSITIONS
EQUATIONS
FLUIDS
FREQUENCY RANGE
GASES
LAWS
LAYERS
MATERIALS
NONMETALS
PARTIAL DIFFERENTIAL EQUATIONS
RARE GASES