AVS 51st International Symposium
    Thin Films Thursday Sessions
       Session TF-ThM

Paper TF-ThM11
Integrated Modeling of Al@sub 2@O@sub 3@ Atomic Layer Deposition

Thursday, November 18, 2004, 11:40 am, Room 303C

Session: Modeling & Fundamentals in Thin Film Deposition
Presenter: H. Simka, Intel Corp.
Authors: H. Simka, Intel Corp.
D. Thakurta, Intel Corp.
S. Shankar, Intel Corp.
Correspondent: Click to Email
Atomic Layer Deposition (ALD) has become an increasingly attractive option for deposition of various crucial semiconductor material layers, including high-K dielectrics and barrier metal applications. ALD advantages, which include excellent film coverage, uniformity, composition and thickness targeting, can be realized by optimizing precursor reactivity and process conditions. Fundamental understanding of these factors is often limited, especially for surface reaction pathways involving new materials. One possible approach, based on first-principles quantum chemistry investigations of precursor reactions, is described in this work. The goal of this general approach is to reduce the amount of process characterizations needed, and to complement available surface science and growth data. As an example, Density-Functional Theory was used to determine molecular properties and reaction energy barriers for Al@sub 2@O@sub 3@ ALD with Trimethylaluminum (TMA) and H@sub 2@O precursors, building on results from a previous quantum chemical study (1). A reaction mechanism containing important surface reactions controlling ALD behavior was developed, and integrated with a reactor model. The approach was validated against Al@sub 2@O@sub 3@ ALD data in a well-characterized flow-tube reactor (2). Model predicted growth rates in excellent agreement with data, and explained effects of process conditions (temperature, pressure, precursor cycle-times) on ALD growth. Differences in species reactivity on both alumina (important for growth) and silica substrates (important for nucleation) will be discussed. Acknowledgements: Prof. Steven George (U. Colorado-Boulder), Prof. Charles Musgrave (Stanford U.). References: (1) Y. Widjaja and C.B. Musgrave, Applied Physics Letters, 80(18), 3304 (2002) (2) J.W. Elam, M.D. Groner, and S.M. George, Review of Scientific Instruments, 73(8), 2981 (2002).