AVS 49th International Symposium
    Thin Films Wednesday Sessions
       Session TF+VT-WeM

Invited Paper TF+VT-WeM1
The PE-ALD of Ta Based Metals/Nitrides: The Growth, Materials Properties, and Applications to Future Device Fabrications

Wednesday, November 6, 2002, 8:20 am, Room C-101

Session: Atomic Layer Deposition - Barriers & Nitrides
Presenter: H. Kim, IBM T.J. Watson Research Center
Authors: H. Kim, IBM T.J. Watson Research Center
S.M. Rossnagel, IBM T.J. Watson Research Center
Correspondent: Click to Email
Thin film deposition techniques producing high quality and highly conformal films with atomic level control are increasingly required as semiconductor device size shrinks into nanoscale regime. Atomic layer deposition (ALD) is expected to play an important role in depositing thin layers in nanoscale Si device manufacturing. Plasma enhancement of the process allows deposition at significantly lower temperatures than both conventional thermal ALD and chemical vapor deposition. Among the key materials used for today's semiconductor processing, thin films of inert, refractory materials will continue to be used in interconnect applications as diffusion barriers, seed and adhesion layers as well as potential front end applications such as contacts or gate metallization. In this presentation, the Ta-based ALD systems have been explored at low temperature for a variety of semiconductor devices applications. Ta-based metals/nitrides films were grown by plasma-enhanced atomic layer deposition (PE-ALD) at temperatures from room temperature up to 400 °C using an inorganic halide source and RF plasma-produced atomic H as metal precursor and the reducing agent, respectively. The growth mechanism, microstructure, and chemical composition were studied using various ex situ analyses techniques. Good quality films with low contamination levels were obtained at low growth temperatures. Additionally, thermal stability, diffusion barrier property, resistivity, and other electrical properties, which are the essential materials properties for semiconductor device fabrication, were investigated. These results indicate that the PE-ALD process scales to manufacturing dimensions and applications and will facilitate the extension of interconnect technology beyond 100 nm dimensions.