1. ALD on particles MT-0.6067 Thin Film Technology Student talk by Teemu Perkkiö

2. Introduction  Modifying surface properties  Particle size ~1 nm – 50 µm  Typical film thickness 1 – 50 nm  Uniform coatings are required Surface area as a function of particle size (Rahman, Padavettan 2012)

3. How does this relate to ALD?

4. Fluidized bed reactor (FBR)  Concept of fluidization  How particles are perceived by gases  Principles of FBR Schematic of FBR (King et al. 2007) a) Dosing zone b) Particle bed c) Splash zone d) Mechanical stirrer e) Precursor bubbler f) Outlet

5. Rotary tube reactor  Concept of agitation  Principles of rotary reactor  Efficiency compared to FBR Simple schematic of rotary tube reactor (McCormick et al. 2007)

6. Applications  Drug delivery, thermal fillers, nanofillers etc.  Fastening to surface  Corrosion barrier  Controlling diffusion properties  Example: BN particles in microelectronics TEM image of Alumina coated BN (Weimer, 2004)

7. Key points  Requirement for high precision  Fluidization and agitation are important methods  Wide variety of applications

8. References 1.GEORGE, S., 2010. Atomic Layer Deposition: An Overview. Chem. Rev., 2010, 110 (1), pp 111– 131 2.KING, D.M., SPENCER II, J.A., LIANG, X., HAKIM, L.F. and WEIMER, A.W., 2007. Atomic layer deposition on particles using a fluidized bed reactor with in situ mass spectrometry. Surface and Coatings Technology, 201(22–23), pp. 9163-9171. 3.MCCORMICK, J., CLOUTIER, B., WEIMER, A. and GEORGE, S., 2007. Rotary reactor for atomic layer deposition on large quantities of nanoparticles. Journal of Vacuum Science & Technology A, 25(1), pp. 67-74. 4.MEESTERS, G., VALDESUEIRO, D. and RUUD VAN OMMEN, J., 2013. Coating Fine Particles With Ultra Thin Films Using Atomic Layer Deposition. 2013 AIChE Annual Meeting. 5.RAHMAN, I.A. and PADAVETTAN, V., 2012. Synthesis of silica nanoparticles by sol-gel: size- dependent properties, surface modification, and applications in silica-polymer nanocomposites—a review. Journal of Nanomaterials, 2012, pp. 8. 6.WEIMER, A.W., 2004. Particle Coating by Atomic Layer Deposition (ALD). Partec 2004.

9. Thank you for your attention!