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Title: Comparison of tungsten films grown by CVD and hot-wire assisted atomic layer deposition in a cold-wall reactor

Abstract

In this work, the authors developed hot-wire assisted atomic layer deposition (HWALD) to deposit tungsten (W) with a tungsten filament heated up to 1700–2000 °C. Atomic hydrogen (at-H) was generated by dissociation of molecular hydrogen (H{sub 2}), which reacted with WF{sub 6} at the substrate to deposit W. The growth behavior was monitored in real time by an in situ spectroscopic ellipsometer. In this work, the authors compare samples with tungsten grown by either HWALD or chemical vapor deposition (CVD) in terms of growth kinetics and properties. For CVD, the samples were made in a mixture of WF{sub 6} and molecular or atomic hydrogen. Resistivity of the WF{sub 6}-H{sub 2} CVD layers was 20 μΩ·cm, whereas for the WF{sub 6}-at-H-CVD layers, it was 28 μΩ·cm. Interestingly, the resistivity was as high as 100 μΩ·cm for the HWALD films, although the tungsten films were 99% pure according to x-ray photoelectron spectroscopy. X-ray diffraction reveals that the HWALD W was crystallized as β-W, whereas both CVD films were in the α-W phase.

Authors:
; ; ; ; ;  [1]
  1. MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands)
Publication Date:
OSTI Identifier:
22489762
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 34; Journal Issue: 1; Other Information: (c) 2015 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 42 ENGINEERING; CHEMICAL VAPOR DEPOSITION; COMPARATIVE EVALUATIONS; ELLIPSOMETERS; FILAMENTS; FILMS; HYDROGEN; SUBSTRATES; TUNGSTEN; WIRES; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Yang, Mengdi, E-mail: M.Yang@utwente.nl, Aarnink, Antonius A. I., Kovalgin, Alexey Y., Gravesteijn, Dirk J., Wolters, Rob A. M., and Schmitz, Jurriaan. Comparison of tungsten films grown by CVD and hot-wire assisted atomic layer deposition in a cold-wall reactor. United States: N. p., 2016. Web. doi:10.1116/1.4936387.
Yang, Mengdi, E-mail: M.Yang@utwente.nl, Aarnink, Antonius A. I., Kovalgin, Alexey Y., Gravesteijn, Dirk J., Wolters, Rob A. M., & Schmitz, Jurriaan. Comparison of tungsten films grown by CVD and hot-wire assisted atomic layer deposition in a cold-wall reactor. United States. doi:10.1116/1.4936387.
Yang, Mengdi, E-mail: M.Yang@utwente.nl, Aarnink, Antonius A. I., Kovalgin, Alexey Y., Gravesteijn, Dirk J., Wolters, Rob A. M., and Schmitz, Jurriaan. 2016. "Comparison of tungsten films grown by CVD and hot-wire assisted atomic layer deposition in a cold-wall reactor". United States. doi:10.1116/1.4936387.
@article{osti_22489762,
title = {Comparison of tungsten films grown by CVD and hot-wire assisted atomic layer deposition in a cold-wall reactor},
author = {Yang, Mengdi, E-mail: M.Yang@utwente.nl and Aarnink, Antonius A. I. and Kovalgin, Alexey Y. and Gravesteijn, Dirk J. and Wolters, Rob A. M. and Schmitz, Jurriaan},
abstractNote = {In this work, the authors developed hot-wire assisted atomic layer deposition (HWALD) to deposit tungsten (W) with a tungsten filament heated up to 1700–2000 °C. Atomic hydrogen (at-H) was generated by dissociation of molecular hydrogen (H{sub 2}), which reacted with WF{sub 6} at the substrate to deposit W. The growth behavior was monitored in real time by an in situ spectroscopic ellipsometer. In this work, the authors compare samples with tungsten grown by either HWALD or chemical vapor deposition (CVD) in terms of growth kinetics and properties. For CVD, the samples were made in a mixture of WF{sub 6} and molecular or atomic hydrogen. Resistivity of the WF{sub 6}-H{sub 2} CVD layers was 20 μΩ·cm, whereas for the WF{sub 6}-at-H-CVD layers, it was 28 μΩ·cm. Interestingly, the resistivity was as high as 100 μΩ·cm for the HWALD films, although the tungsten films were 99% pure according to x-ray photoelectron spectroscopy. X-ray diffraction reveals that the HWALD W was crystallized as β-W, whereas both CVD films were in the α-W phase.},
doi = {10.1116/1.4936387},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 1,
volume = 34,
place = {United States},
year = 2016,
month = 1
}
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