IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Dielectrics Wednesday Sessions
       Session DI-WeM

Invited Paper DI-WeM9
Deposition of Ultra Thin Films by Atomic layer Deposition (ALD)

Wednesday, October 31, 2001, 11:00 am, Room 130

Session: Atomic Layer Deposition for Silicon Devices
Presenter: M.A. Leskela, University of Helsinki, Finland
Correspondent: Click to Email
In ALD the precursors are pulsed to the substrate alternately one at the time and between the reactant pulses the reactor is purged with an inert gas. With a proper adjustment of the conditions the process can proceed via saturative steps. The precursors chemisorb on the surface or react with the surface groups and form a tightly bound monolayer. Under such conditions the growth is stable and the thickness increase is constant in each deposition cycle. The layer-by-layer principle facilitates the growth of ultra thin films with accurate thickness and conformality on large areas. These advantages of the ALD method are just those required in microelectronics for the manufacturing of future generation integrated circuits. In microelectronics ALD has been studied for deposition of oxide films for dielectrics, nitride films for diffusion barriers for metallizations, and metal films. Examples of those processes will be given. The key issue in a successful ALD process is the precursor chemistry. The development of new precursors is a challenge for the further progress of ALD. ALD can also be used to modify interfaces of thin film structures and surfaces of powder samples. Examples from the use of ALD in preparation of heterogeneous catalysts will be highlighted.