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

Paper DI-WeM2
Quantum Chemical Study of Zirconium Oxide Atomic Layer Deposition

Wednesday, October 31, 2001, 8:40 am, Room 130

Session: Atomic Layer Deposition for Silicon Devices
Presenter: Y. Widjaja, Stanford University
Authors: Y. Widjaja, Stanford University
C.B. Musgrave, Stanford University
Correspondent: Click to Email
As gate oxide thickness in MOS device decreases, new high-@kappa@ materials are being investigated to substitute for silicon oxide. However, unlike silicon oxide, the oxide layers being investigated do not react readily on silicon surfaces. Here, we use density functional theory to examine the atomic layer deposition of zirconium oxide, one of the high-@kappa@ materials candidates, on the Si(100)-(2x1) surface. The reactants investigated in this study are ZrCl@sub 4@ and H@sub 2@O. The atomistic mechanisms of two different deposition cycles are investigated: 1) ZrCl@sub 4@ is first deposited on the clean Si(100)-(2x1) surface. Upon adsorption, ZrCl@sub 4@ is shown to dissociate into ZrCl@sub 3@(a) and Cl(a) with an activation barrier that is below the entry level. Water is deposited next and various surface reactions and configurations are investigated. We find that the most stable species consists of ZrCl@sub 3@(a) and OH(a) attached to the two silicon atoms of silicon dimers. Alternatively, 2) H@sub 2@O is first deposited on the Si(100)-(2x1) surface. As determined previously, we also find that H@sub 2@O dissociates into OH(a) and H(a) upon adsorption. Subsequent reactions with ZrCl@sub 4@ are then investigated. Upon investigation of the two different deposition cycles, the properties of the interfacial layer between silicon and zirconium oxide are then investigated. Subsequent half cycle reactions on the zirconia surface will also be presented.