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Title: Effects of in situ N{sub 2} plasma treatment on etch of HfO{sub 2} in inductively coupled Cl{sub 2}/N{sub 2} plasmas

Abstract

The etch selectivity of HfO{sub 2} to Si reported to date is poor. To improve the selectivity, one needs to either increase the etch rate of HfO{sub 2} or decrease the etch rate of Si. In this work, the authors investigate the etch selectivity of HfO{sub 2} in Cl{sub 2}/N{sub 2} plasmas. In particular, the effects of in situ N{sub 2} plasma treatment of HfO{sub 2} and Si were investigated. The silicon substrate was exposed to nitrogen plasma and was nitrided, which was confirmed by x-ray photoelectron spectroscopy. The nitrided Si etching was suppressed in Cl{sub 2}/N{sub 2} plasmas. The effectiveness of nitridation was studied with varying the plasma power, bias power, pressure, and N{sub 2} plasma exposure time. The results show that the etch resistance increased with increased power and decreased pressure. A minimum exposure time was required to obtain etch resistant property. The applied bias power increased the etch rate of Si substrate, so it should not be used during N{sub 2} plasma treatment. Fortunately, the etch rate of HfO{sub 2} was increased by the nitridation process. Therefore, HfO{sub 2}/Si selectivity can be improved by nitridation and became higher than 5 under proper exposure condition.

Authors:
; ; ; ; ; ;  [1];  [2]
  1. Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30043, Taiwan (China)
  2. (China)
Publication Date:
OSTI Identifier:
20979374
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: 3; Other Information: DOI: 10.1116/1.2731361; (c) 2007 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CHLORINE; DIELECTRIC MATERIALS; ETCHING; HAFNIUM OXIDES; NITRIDATION; NITROGEN; PLASMA; SEMICONDUCTOR MATERIALS; SILICON; SUBSTRATES; THIN FILMS; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Lin Chaung, Leou, K.-C., Fan, Y.-C., Li, T.-C., Chang, K.-H., Lee, L.-S., Tzeng, P.-J., and Electronic Research and Service Organization, Industrial Technology Research Institute, Hsinchu 30043, Taiwan. Effects of in situ N{sub 2} plasma treatment on etch of HfO{sub 2} in inductively coupled Cl{sub 2}/N{sub 2} plasmas. United States: N. p., 2007. Web. doi:10.1116/1.2731361.
Lin Chaung, Leou, K.-C., Fan, Y.-C., Li, T.-C., Chang, K.-H., Lee, L.-S., Tzeng, P.-J., & Electronic Research and Service Organization, Industrial Technology Research Institute, Hsinchu 30043, Taiwan. Effects of in situ N{sub 2} plasma treatment on etch of HfO{sub 2} in inductively coupled Cl{sub 2}/N{sub 2} plasmas. United States. doi:10.1116/1.2731361.
Lin Chaung, Leou, K.-C., Fan, Y.-C., Li, T.-C., Chang, K.-H., Lee, L.-S., Tzeng, P.-J., and Electronic Research and Service Organization, Industrial Technology Research Institute, Hsinchu 30043, Taiwan. Tue . "Effects of in situ N{sub 2} plasma treatment on etch of HfO{sub 2} in inductively coupled Cl{sub 2}/N{sub 2} plasmas". United States. doi:10.1116/1.2731361.
@article{osti_20979374,
title = {Effects of in situ N{sub 2} plasma treatment on etch of HfO{sub 2} in inductively coupled Cl{sub 2}/N{sub 2} plasmas},
author = {Lin Chaung and Leou, K.-C. and Fan, Y.-C. and Li, T.-C. and Chang, K.-H. and Lee, L.-S. and Tzeng, P.-J. and Electronic Research and Service Organization, Industrial Technology Research Institute, Hsinchu 30043, Taiwan},
abstractNote = {The etch selectivity of HfO{sub 2} to Si reported to date is poor. To improve the selectivity, one needs to either increase the etch rate of HfO{sub 2} or decrease the etch rate of Si. In this work, the authors investigate the etch selectivity of HfO{sub 2} in Cl{sub 2}/N{sub 2} plasmas. In particular, the effects of in situ N{sub 2} plasma treatment of HfO{sub 2} and Si were investigated. The silicon substrate was exposed to nitrogen plasma and was nitrided, which was confirmed by x-ray photoelectron spectroscopy. The nitrided Si etching was suppressed in Cl{sub 2}/N{sub 2} plasmas. The effectiveness of nitridation was studied with varying the plasma power, bias power, pressure, and N{sub 2} plasma exposure time. The results show that the etch resistance increased with increased power and decreased pressure. A minimum exposure time was required to obtain etch resistant property. The applied bias power increased the etch rate of Si substrate, so it should not be used during N{sub 2} plasma treatment. Fortunately, the etch rate of HfO{sub 2} was increased by the nitridation process. Therefore, HfO{sub 2}/Si selectivity can be improved by nitridation and became higher than 5 under proper exposure condition.},
doi = {10.1116/1.2731361},
journal = {Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films},
number = 3,
volume = 25,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}