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Title: Forced convection and transport effects during hyperbaric laser chemical vapor deposition

Abstract

This work explores mass transport processes during HP-LCYD, including the transverse forced-flow of precursor gases through a nozzle to enhance fiber growth rates. The use of laser trapping and suspension of nano-scale particles in the precursor flow is also described, providing insights into the nature of the gas flow, including jetting from the fiber tip and thermodiffusion processes near the reaction zone. The effects of differing molecular-weight buffer gases is also explored in conjunction with the Soret effect, and it is found that nucleation at the deposit surface (and homogeneous nucleation in the gas phase) can be enhanced/ retarded, depending on the buffer gas molecular weight. To demonstrate that extensive microstructures can be grown simultaneously, three-dimensional fiber arrays are also grown in-parallel using diffractive optics--without delatory effects from neighboring reaction sites.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2]
  1. Los Alamos National Laboratory
  2. UPPSALA UNIV
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
956470
Report Number(s):
LA-UR-09-00055; LA-UR-09-55
TRN: US201013%%179
DOE Contract Number:
AC52-06NA25396
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics A
Country of Publication:
United States
Language:
English
Subject:
36; CHEMICAL VAPOR DEPOSITION; FORCED CONVECTION; GAS FLOW; LASERS; MOLECULAR WEIGHT; THERMAL DIFFUSION; TRANSPORT

Citation Formats

Maxwell, James L, Chavez, Craig A, Espinoza, Miguel, Black, Marcie, Maskaly, Karlene, and Boman, Mats. Forced convection and transport effects during hyperbaric laser chemical vapor deposition. United States: N. p., 2009. Web.
Maxwell, James L, Chavez, Craig A, Espinoza, Miguel, Black, Marcie, Maskaly, Karlene, & Boman, Mats. Forced convection and transport effects during hyperbaric laser chemical vapor deposition. United States.
Maxwell, James L, Chavez, Craig A, Espinoza, Miguel, Black, Marcie, Maskaly, Karlene, and Boman, Mats. 2009. "Forced convection and transport effects during hyperbaric laser chemical vapor deposition". United States. doi:. https://www.osti.gov/servlets/purl/956470.
@article{osti_956470,
title = {Forced convection and transport effects during hyperbaric laser chemical vapor deposition},
author = {Maxwell, James L and Chavez, Craig A and Espinoza, Miguel and Black, Marcie and Maskaly, Karlene and Boman, Mats},
abstractNote = {This work explores mass transport processes during HP-LCYD, including the transverse forced-flow of precursor gases through a nozzle to enhance fiber growth rates. The use of laser trapping and suspension of nano-scale particles in the precursor flow is also described, providing insights into the nature of the gas flow, including jetting from the fiber tip and thermodiffusion processes near the reaction zone. The effects of differing molecular-weight buffer gases is also explored in conjunction with the Soret effect, and it is found that nucleation at the deposit surface (and homogeneous nucleation in the gas phase) can be enhanced/ retarded, depending on the buffer gas molecular weight. To demonstrate that extensive microstructures can be grown simultaneously, three-dimensional fiber arrays are also grown in-parallel using diffractive optics--without delatory effects from neighboring reaction sites.},
doi = {},
journal = {Applied Physics A},
number = ,
volume = ,
place = {United States},
year = 2009,
month = 1
}
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