Ultrathin, Conformal Coatings on Particles

Particles have many technological applications and are used to make a variety of composite materials. Coatings on particles can be used to change the surface properties while retaining the bulk properties. Coatings can also be used to functionalize, protect, strengthen or modify the properties of the particle. Despite the importance of coating particles, very few methods exist to deposit conformal thin films on particles.

Our previous work has developed ALD techniques to coat particles with ultrathin and conformal films. Recent investigations have studied Al2O3 [1] and SiO2 [2] deposition on BN particles, BN deposition on ZrO2 particles [3], and SiO2 on BaTiO3 particles. We have also demonstrated Al2O3 deposition on low-density polyethylene particles. Many of these studies are conducted using Fourier Transform Infrared (FTIR) spectroscopy because the particles have a very high surface area that facilitates these FTIR investigations. A transmission electron micrograph (TEM) of a Al2O3 ALD coating on a BN particle is shown in the accompanying figure.

 

References

  1. J.D. Ferguson, A.W. Weimer and S.M. George, "Atomic Layer Deposition of Ultrathin and Conformal Al2O3 Films on BN Particles", Thin Solid Films 371, 95-104 (2000).
  2. J.D. Ferguson, A.W. Weimer and S.M. George, "Atomic Layer Deposition of SiO2 Films on BN Particles Using Sequential Surface Reactions", Chem. Mater. 12, 3472-3480 (2000).
  3. J.D. Ferguson, A.W. Weimer and S.M. George, "Atomic Layer Deposition of Boron Nitride Using Sequential Exposures of BCl3 and NH3", Thin Solid Films 413, 16-24 (2002).

To download a PDF of this document, click here.

 

Back to Projects