Supersonic jet deposition of silver nanoparticle aerosols: Correlations of impact conditions and film morphologies
- Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712 (United States)
We describe experiments and modeling for the deposition of silver lines and films via the impaction of a silver nanoparticle aerosol delivered through a supersonic jet. The aerosol gas dynamics of the jet flow field, nanoparticle acceleration in the jet, and deposition by impaction onto the substrate were modeled for both a flat-plate nozzle and for a conical nozzle designed to obtain higher impaction velocities. We modeled nanoparticle dynamics for He, Ar, and N{sub 2} gasses, all initially at room temperature and 1 atm pressure, flowing through a 250 {mu}m orifice into vacuum with a pressure ratio of {approx}5000. Experiments were conducted to deposit silver nanoparticle aerosols under the same conditions as were modeled. The silver nanoparticles were generated by laser ablation of a flowing microparticle aerosol entrained in either He or Ar that produced nanoparticles 5-10 and 15-20 nm in diameter, respectively. Deposition was made onto an unheated substrate in vacuum. The morphology of the deposited films was determined by scanning electron microscope cross-section images and crystallite size was determined by x-ray diffraction analysis. The morphological features and crystallite size were correlated with the nanoparticle impaction velocity and impaction energy derived from the model. We found that, for a given gas type, the size of the grains and morphological features within the impacted films were similar to the size of the nanoparticles from which the films were formed. The density and the degree of consolidation of the films were highly dependent on the nanoparticle impaction velocity/energy and were highest for helium. Control of film morphology, grain size, and film density during supersonic impaction of nanoparticle aerosols are discussed in light of these results.
- OSTI ID:
- 20982778
- Journal Information:
- Journal of Applied Physics, Vol. 101, Issue 6; Other Information: DOI: 10.1063/1.2710304; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effects of Al content on grain growth of solid solution (Ti,Al)N films
Mass, momentum, and energy transfer in supersonic aerosol deposition processes