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Title: Microstructure, mechanical and electrical properties of nanocrystalline W-Mo thin films

Authors:
 [1];  [1]
  1. Department of Mechanical Engineering, University of Texas at El Paso, El Paso, Texas 79968, USA
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1410857
Grant/Contract Number:
NA0000979
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
AIP Advances
Additional Journal Information:
Journal Volume: 7; Journal Issue: 12; Related Information: CHORUS Timestamp: 2017-12-01 08:39:19; Journal ID: ISSN 2158-3226
Publisher:
American Institute of Physics
Country of Publication:
United States
Language:
English

Citation Formats

Martinez, G., and Ramana, C. V. Microstructure, mechanical and electrical properties of nanocrystalline W-Mo thin films. United States: N. p., 2017. Web. doi:10.1063/1.5009008.
Martinez, G., & Ramana, C. V. Microstructure, mechanical and electrical properties of nanocrystalline W-Mo thin films. United States. doi:10.1063/1.5009008.
Martinez, G., and Ramana, C. V. 2017. "Microstructure, mechanical and electrical properties of nanocrystalline W-Mo thin films". United States. doi:10.1063/1.5009008.
@article{osti_1410857,
title = {Microstructure, mechanical and electrical properties of nanocrystalline W-Mo thin films},
author = {Martinez, G. and Ramana, C. V.},
abstractNote = {},
doi = {10.1063/1.5009008},
journal = {AIP Advances},
number = 12,
volume = 7,
place = {United States},
year = 2017,
month =
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1063/1.5009008

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  • Thin-film silicon allows the fabrication of MEMS devices at low processing temperatures, compatible with monolithic integration in advanced electronic circuits, on large-area, low-cost, and flexible substrates. The most relevant thin-film properties for applications as MEMS structural layers are the deposition rate, electrical conductivity, and mechanical stress. In this work, n{sup +}-type doped hydrogenated amorphous and nanocrystalline silicon thin-films were deposited by RF-PECVD, and the influence of the hydrogen dilution in the reactive mixture, the RF-power coupled to the plasma, the substrate temperature, and the deposition pressure on the structural, electrical, and mechanical properties of the films was studied. Three differentmore » types of silicon films were identified, corresponding to three internal structures: (i) porous amorphous silicon, deposited at high rates and presenting tensile mechanical stress and low electrical conductivity, (ii) dense amorphous silicon, deposited at intermediate rates and presenting compressive mechanical stress and higher values of electrical conductivity, and (iii) nanocrystalline silicon, deposited at very low rates and presenting the highest compressive mechanical stress and electrical conductivity. These results show the combinations of electromechanical material properties available in silicon thin-films and thus allow the optimized selection of a thin silicon film for a given MEMS application. Four representative silicon thin-films were chosen to be used as structural material of electrostatically actuated MEMS microresonators fabricated by surface micromachining. The effect of the mechanical stress of the structural layer was observed to have a great impact on the device resonance frequency, quality factor, and actuation force.« less
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