原子层沉积——Atomic Layer Deposition.ppt

PPT DESIGN PPT DESIGN Atomic Layer Deposition (ALD) Synthetic Chemistry of Materials Outline Outline 1.Introduction to ALD 2.Classical models: ALD of Al2O3 3.ALD and CVD 4.Applications of ALD (1)Coatings on high aspect ratio structures (2)Coatings on Nanoparticles (3)Combination of CNT (4)Plasma ALD 5. Expectations and challenge in ALD 2. Classical models: ALD of Al2O3 The overall reaction for Al2O3 ALD 2Al(CH3)3+ 3H2O Al2O3+3CH4 ?H=376 kcal The surface chemistry during Al2O3 ALD (a) AlOH* + Al(CH3)3 AlOAl(CH3)2*+CH4 (b) AlCH3* + H2O AlOH*+CH4 Characters 5 High repeatability and expansibility 6 Substrate（Large and high aspect ratio） 4 Pinhole-free films 3 Conformal deposition 2 Self-limiting 1 Atomic level control 1. Introduction to ALD Atomic layer deposition （ALD） — atomic level control of film deposition 3. Comparison of ALD and CVD Schematic pressure profile during the ALD and CVD process Seung-Mo Lee et al., ChemPhysChem, 12, 791-798(2011) 3. Comparison of ALD and CVD Sequential introduction of precursors Synchronous introduction of precursors ALD CVD Better step coverage Existing shadowing effects Atomic level control I can’t 1 2 M. Knaut, et al. Microelectron Eng, 107, 80-83 (2013) 4.1 Coatings on high aspect ratio structures Coating on step-like sructures 1 Coating on multi-pore structures 2 4.2 Coatings on nanoparticles PS spheres self assembled ALD of TiCl4 and H2O Ion milling Etching?PS?hemispheres Annealing Xu Dong Wang et al., Nano letters Vol.4,No.11 (2004) 4.2 Coatings on nanoparticles ALD?Cycles → Bowl?Thickness PS Spheres → Bowl Size 4.3 Combination of CNT and super-black coatings Schematic illustration of the ALD and CVD process for the synthesis of CNT arrays Schematic representation of Al2O3 ALD coating on monodispersed NPs. 4.3 Combination of CNT and super-black coatings Kai Zhou, et al., Nanoscale Res Lett, 5:1