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Characteristics of Amorphous Silicon Gate Etching in Cl2/HBr/O2 High Density Plasma  

Lee, Won Gyu (Deptartment of Chemical Engineering, Kangwon National University)
Publication Information
Korean Chemical Engineering Research / v.47, no.1, 2009 , pp. 79-83 More about this Journal
Abstract
In this study, the characteristics of amorphous silicon etching for the formation of gate electrodes have been evaluated at the variation of several process parameters. When total flow rates composed of $Cl_2/HBr/O_2$ gas mixtures increased, the etch rate of amorphous silicon layer increased, but critical dimension (CD) bias was not notably changed regardless of total flow rate. As the amount of HBr in the mixture gas became larger, amorphous silicon etch rate was reduced by the low reactivity of Br species. In the case of increasing oxygen flow rate, etch selectivity was increased due to the reduction of oxide etch rate, enhancing the stability of silicon gate etching process. However, gate electrodes became more sloped according to the increase of oxygen flow rate. Higher source power induced the increase of amorphous silicon etch rate and CD bias, and higher bias power had a tendency to increase the etch rate of amorphous silicon and oxide.
Keywords
Amorphous Silicon; Gate Etch; High Density Plasma; Etch Rate; CD Bias; Selectivity;
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  • Reference
1 Tsou, L. Y., "High Selective Reactive Ion Etching of Polysilicon with Hydrogen Bromide," J. Electrochem. Soc., 136, 3003-3006 (1989)   DOI
2 Box, G., Hunter, W. G. and Hunter, J. S., Statistics for Experimenters, John Wiley & Sons, New York, USA(1975)
3 Bell, F. H. and Joubert, O., "Polysilicon Gate Etching in High Density Plasmas. V. Comparison between Quantitative Chemical Analysis of Photoresist and Oxide Masked Polysilicon Gates Etched in HBr/$CI_2/O_2$ Plasmas," J. Vac. Sci. Technol. B, 15, 88-97 (1997)   DOI   ScienceOn
4 Wolf, S., Silicon Processing for the VLSI Era Vol3- The Submicron MOSFET, Lattice Press, Sunset Beach, CA(1995)
5 Low, C. H., Chin, W. S., Zhou, M. S., Zhong, Q. H. and Chan, L. H., 'Characterization of Si(100) Surfaces after High Density Plasma HBr/$CI_2/O_2$ Etching by AFM and XPS,' 44th National Symposium of American Vacuum Society, San Jose(1997)
6 Joubert, O. and Bell, F. H., "Polysilicon Gate Etching in High- Density Plasmas: Comparison Between Oxide Hard mask and Resist Mask," J. Electrochem. Soc., 144, 1854-1861(1997)   DOI   ScienceOn
7 Zau, G. and Sawin, H., "Effect of $O_2$ Feed Gas Impurity on $CI_2$ Based Plasma Etching of Polysilicon," J. Electrochem. Soc., 139, 250-256(1992)   DOI
8 Tsou, L. Y., 'Effect of Photoresist on Plasma Etching,' J. Electrochem. Soc., 135, 2354-2356(1989)
9 Guinn, K. V., Cheng, C. C. and Donnelly, V. M., "Quantitative Chemical Topography of Polycrystalline Si Anisotropically Etched in $CI_2/O_2$ High Density Plasmas," J. Vac. Sci. Technol. B, 13, 214-226(1995)   DOI   ScienceOn
10 Nakamura, M., Iizuka, K. and Yano, H., "Very High Selectivity n+ poly-Si RIE with Carbon Elimination," Jpn. J. Appl. Phys., 28, 2142-2146(1989)   DOI