AVS 49th International Symposium
    Plasma Science Thursday Sessions
       Session PS+TF-ThM

Paper PS+TF-ThM3
2-Dimensional Plasma Simulation of Reactive Physical Vapor Deposition of Metal Nitride

Thursday, November 7, 2002, 9:00 am, Room C-103

Session: Plasma Enhanced Deposition
Presenter: D. Zhang, Motorola Inc.
Authors: D. Zhang, Motorola Inc.
S. Samavedam, Motorola Inc.
J. Schaeffer, Motorola Inc.
R. Martin, Motorola Inc.
P.L.G. Ventzek, Motorola Inc.
P. Tobin, Motorola Inc.
Correspondent: Click to Email
Reactive physical vapor deposition (RPVD) of metal nitride has been used for interconnect barrier and metal gate deposition due to its relative simplicity in process implementation and lower contamination compared to other deposition techniques requiring chemical precursors. As the electrical properties (e.g. work function, resistivity) of deposited film are sensitive to film characteristics (e.g. composition), optimal process control based on in-depth mechanistic understanding is critical for reactive PVD to meet product requirements. This has motivated our development of a 2-dimensional plasma model for RPVD of metal nitride films. The RPVD model is based on the 2-dimensional Hybrid Plasma Equipment Model (HPEM) developed at the University of Illinois.@footnote 1@ Plasma is approximated as a fluid in HPEM. A target surface nitridation model (TSNM) has been developed to be self-consistently coupled with HPEM. The TSNM uses a site balance algorithm to address neutral adsorption, desorption by ion sputtering, and surface coverages. An effective sputtering yield for the target is used to account for the effect of target nitridation. The model has been applied to study reactive TiN and Ti@sub x@Al@sub y@N deposition using a parallel-plate PVD tool. It is found that athermal neutrals are the dominant source for deposition. Target nitridation impacts deposition rate by reducing sputtering yield. For Ar and N@sub 2@ source gases with a constant total flow, the model derived the dependency of deposition rate with N@sub 2@ flow that is in good agreement with experiments. Impact of various process parameters (gas mixture, power, pressure) on deposition characteristics will also be discussed in this work. @FootnoteText@ @footnote 1@ P. Subramonium and M. J. Kushner, J. Vac. Sci. Technol. A 20, 325 (2002).