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Title: Spatial profile monitoring of etch products of silicon in HBr/Cl{sub 2}/O{sub 2}/Ar plasma

Abstract

The authors have developed a radical-distribution monitoring system for obtaining the spatial profiles of etching products. This system combines Abel inversion and actinometry to estimate the local densities of radicals. The profiles of Si, SiCl, and SiCl{sub 2} in HBr/Cl{sub 2}/O{sub 2}/Ar plasma are captured with this monitoring system. From the gradient analysis of silicon-containing etch products, they found that the source of SiCl{sub 2} is the wafer surface and Si and SiCl are produced in the plasma. In other words, SiCl{sub 2} is produced by the etching reactions on the wafer and diffuses into the plasma to be the source of Si or SiCl through dissociation. In the etcher used for this experiment, etching gases are supplied from a top plate inducing downward flows. At a pressure as low as 0.4 Pa, the effect of convection on etch products is also observed. Increasing total gas flow rate intensifies convection and changes the spatial profile of SiCl{sub 2}. However, on the wafer surface, the convective effect saturated at a total flow rate of 200 SCCM (SCCM denotes cubic centimeter per minute at STP). The ratio of the emission intensities of SiCl{sub 2} and supplied etching gases was found to bemore » a convenient index for visualizing the effect of gas flow. The shapes of the gas jet from both 170- and 50-mm-diameter gas inlets were drawn in contour plots. The jet from the narrow inlet swept away the etch products in the center of the wafer.« less

Authors:
;  [1]
  1. Central Research Laboratory, Hitachi, Ltd., 1-280 Higashi-koigakubo, Kokubunji, Tokyo 185-8601 (Japan)
Publication Date:
OSTI Identifier:
20979394
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films; Journal Volume: 25; Journal Issue: 2; Other Information: DOI: 10.1116/1.2539295; (c) 2007 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CHLORINE; ETCHING; FLOW RATE; GAS FLOW; HYDROBROMIC ACID; MONITORING; PLASMA; PLASMA DENSITY; PLASMA DIAGNOSTICS; PLASMA JETS; RADICALS; SEMICONDUCTOR MATERIALS; SILICON; SILICON CHLORIDES

Citation Formats

Tanaka, Junichi, and Miya, Go. Spatial profile monitoring of etch products of silicon in HBr/Cl{sub 2}/O{sub 2}/Ar plasma. United States: N. p., 2007. Web. doi:10.1116/1.2539295.
Tanaka, Junichi, & Miya, Go. Spatial profile monitoring of etch products of silicon in HBr/Cl{sub 2}/O{sub 2}/Ar plasma. United States. doi:10.1116/1.2539295.
Tanaka, Junichi, and Miya, Go. Thu . "Spatial profile monitoring of etch products of silicon in HBr/Cl{sub 2}/O{sub 2}/Ar plasma". United States. doi:10.1116/1.2539295.
@article{osti_20979394,
title = {Spatial profile monitoring of etch products of silicon in HBr/Cl{sub 2}/O{sub 2}/Ar plasma},
author = {Tanaka, Junichi and Miya, Go},
abstractNote = {The authors have developed a radical-distribution monitoring system for obtaining the spatial profiles of etching products. This system combines Abel inversion and actinometry to estimate the local densities of radicals. The profiles of Si, SiCl, and SiCl{sub 2} in HBr/Cl{sub 2}/O{sub 2}/Ar plasma are captured with this monitoring system. From the gradient analysis of silicon-containing etch products, they found that the source of SiCl{sub 2} is the wafer surface and Si and SiCl are produced in the plasma. In other words, SiCl{sub 2} is produced by the etching reactions on the wafer and diffuses into the plasma to be the source of Si or SiCl through dissociation. In the etcher used for this experiment, etching gases are supplied from a top plate inducing downward flows. At a pressure as low as 0.4 Pa, the effect of convection on etch products is also observed. Increasing total gas flow rate intensifies convection and changes the spatial profile of SiCl{sub 2}. However, on the wafer surface, the convective effect saturated at a total flow rate of 200 SCCM (SCCM denotes cubic centimeter per minute at STP). The ratio of the emission intensities of SiCl{sub 2} and supplied etching gases was found to be a convenient index for visualizing the effect of gas flow. The shapes of the gas jet from both 170- and 50-mm-diameter gas inlets were drawn in contour plots. The jet from the narrow inlet swept away the etch products in the center of the wafer.},
doi = {10.1116/1.2539295},
journal = {Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films},
number = 2,
volume = 25,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}