skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Numerical Simulation of High Density Infrared Processing of FePt Nanoparticle Films

Abstract

This papers deals with the high-density plasma-arc processing of FePt nanoparticle films. For short processing times, different materials, and multiple length scales of the system considered, the estimation of the optimum combination of process parameters is a difficult task. The process parameters can be obtained efficiently from a combined experimental and computational process analysis. The development of a computational methodology for plasma-arc processing is presented. Data on material properties are used to simplify the analytical model. An effective extinction coefficient was used to describe the absorption of the radiation into the nanofilm. Experimental data for the surface temperature of the FePt nanofilm were obtained by infrared measurements. Parameters needed for the energy transport model were identified based on measured temperature data. The model presented can be used to formulate process schedules for given time-temperature constraints.

Authors:
 [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
931632
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the Minerals Metals & Materials Society (JOM); Journal Volume: 58; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; IRON ALLOYS; PLATINUM ALLOYS; NANOSTRUCTURES; ABSORPTION; INFRARED RADIATION; FILMS; MATHEMATICAL MODELS

Citation Formats

Sabau, Adrian S, and Dinwiddie, Ralph Barton. Numerical Simulation of High Density Infrared Processing of FePt Nanoparticle Films. United States: N. p., 2006. Web.
Sabau, Adrian S, & Dinwiddie, Ralph Barton. Numerical Simulation of High Density Infrared Processing of FePt Nanoparticle Films. United States.
Sabau, Adrian S, and Dinwiddie, Ralph Barton. Sun . "Numerical Simulation of High Density Infrared Processing of FePt Nanoparticle Films". United States. doi:.
@article{osti_931632,
title = {Numerical Simulation of High Density Infrared Processing of FePt Nanoparticle Films},
author = {Sabau, Adrian S and Dinwiddie, Ralph Barton},
abstractNote = {This papers deals with the high-density plasma-arc processing of FePt nanoparticle films. For short processing times, different materials, and multiple length scales of the system considered, the estimation of the optimum combination of process parameters is a difficult task. The process parameters can be obtained efficiently from a combined experimental and computational process analysis. The development of a computational methodology for plasma-arc processing is presented. Data on material properties are used to simplify the analytical model. An effective extinction coefficient was used to describe the absorption of the radiation into the nanofilm. Experimental data for the surface temperature of the FePt nanofilm were obtained by infrared measurements. Parameters needed for the energy transport model were identified based on measured temperature data. The model presented can be used to formulate process schedules for given time-temperature constraints.},
doi = {},
journal = {Journal of the Minerals Metals & Materials Society (JOM)},
number = 6,
volume = 58,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
  • Pulse thermal processing (PTP) of FePt nanoparticle films was studied using a high density infrared (HDI) plasma arc lamp. FePt nanoparticle films on silicon substrates were processed using 0.25- second infrared (IR) pulses. The processing was aimed at reaching a peak target temperature for multiple pulses of 550 C. Numerical simulations of the heat transfer for the PTP were performed to determine the operating power levels for the plasma arc lamp. Infrared measurements were conducted to obtain experimental data for the surface temperature of the FePt nanofilm. Parameters needed for the heat-transfer model were identified based on the experimental temperaturemore » results. Following the model validation, several numerical simulations were performed to estimate the power levels. It was shown that the FePt nanoparticle films were successfully processed using the power levels provided by the heat-transfer analysis.« less
  • The effect of pulsed-thermal-processing with high-density plasma arc heating is discussed for 20 nm thick nanocrystalline FePt thin films. The dependence of the A1 {yields} L1{sub 0} phase transformation on pulsed time and radiant energy of the pulse is quantified through x-ray diffraction and alternating gradient magnetometry. For 100 ms and 250 ms pulse widths, the phase transformation was observed. Higher radiant energy densities resulted in a larger measured coercivity associated with the L1{sub 0} phase.
  • We investigated magnetic properties and L1{sub 0} phase formation of FePt films by rapid thermal annealing (RTA) and high current-density ion-beam irradiation. The sample prepared by RTA at 550 deg. C has (001) texture and strong magnetic perpendicular anisotropy with H{sub c} equal to 6 kOe. The sample irradiated at 5.04 {mu}A/cm{sup 2} has H{sub c} equal to 10 kOe but has isotropic magnetic properties due to the (111) texture. The magnetic correlation length of the ion-irradiated sample was about twice as large as that of the RTA sample. This may be due to the inhomogeneity of the L1{sub 0}more » phase formation in the ion-irradiated film.« less
  • FePt-X (X=C, TiO{sub 2}, Ta{sub 2}O{sub 5}) nanocomposite films were deposited on MgO/CrRu/glass substrates at 350 deg. C by magnetron cosputtering. The comparison investigations on the magnetic properties and microstructure of FePt-X films with various dopants were conducted. All FePt-X films showed (001) preferred orientation and oxide dopants promoted the formation of magnetically soft fcc FePt phase. With 15 vol % C doping, FePt-C film with columnar grains of 7.5 nm was obtained and the out-of-plane coercivity measured at room temperature was as high as 14.4 kOe. The increase in carbon volume fraction to 20% caused the formation of two-layermore » structure, whereas for the 20 vol % TiO{sub 2} and Ta{sub 2}O{sub 5} doping, the columnar structure of the FePt films remained and the corresponding grain sizes were 5 and 10 nm, respectively. Ta{sub 2}O{sub 5} doping showed better grain isolation than the others. The out-of-plane coercivities of FePt-TiO{sub 2} and FePt-Ta{sub 2}O{sub 5} films were 7.5 and 8.8 kOe, respectively.« less
  • No abstract prepared.