| 초록 |
Atomic layer deposition (ALD) is a thin film deposition method that employs surface self-saturated reactions. Due to the excellent conformality of ALD, ALD is expected to be one of the key tools for nanoscale device fabrication. Since ALD films are deposited by only surface reactions, ALD growth can be controlled by controlling surface properties. In this presentation, we will describe methods to prepare patterned metal ALD films and ALD nanoparticles (NPs), and will present a modeling result to illustrate nucleation in ALD. Octadecyltrichlorosilane (ODTS) self-assembled monolayer (SAM) was used as an agent for surface property control. The ODTS SAMs formed on original SiO2 surface change the surface property from active to inert surface toward ALD reaction. Co ALD films are easily formed on ODTS-free region but not on ODTS-coated region. By using patterned ODTS SAMs, 3 μm-width Co line patterns are obtained without etching process. Defects in the ODTS SAM resulting from incomplete formation time in solution serve as nucleation sites for ALD Pt. NPs are deposited on a defective SAM template, and the aerial density and mean diameter of the NPs can be controlled by changing the SAM dip time and the number of ALD cycles. An isothermal nucleation model is developed in which several nucleation behaviors are considered in comparison with experimental data. The results show that the model incorporating nucleation incubation provides the best fit to the experimental data. |
