IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Plasma Science Monday Sessions
       Session PS1-MoA

Paper PS1-MoA10
Arc Generation from Sputtering Plasma-Dielectric Inclusion Interactions

Monday, October 29, 2001, 5:00 pm, Room 103

Session: Plasma-Surface Interactions I
Presenter: C.E. Wickersham, Tosoh SMD, Inc.
Authors: C.E. Wickersham, Tosoh SMD, Inc.
J.E. Poole, Tosoh SMD, Inc.
A. Leybovich, Tosoh SMD, Inc.
J. Fan, Tosoh SMD, Inc.
L. Zhu, Tosoh SMD, Inc.
Correspondent: Click to Email
Arcing during sputtering and etching is a significant cause of particle defect generation during device fabrication. The size of the dielectric inclusion plays a major role in determining if arcing occurs and particle defects are generated. We studied the effect of inclusion size, material type and plasma conditions on the propensity for arcing during sputtering of aluminum targets. We have found that there is a critical inclusion size required for arcing to occur. The critical size for Al@sub 2@O@sub 3@ inclusions in an aluminum target under typical magnetron sputtering conditions is 440 ± 160 µm. Inclusions with sizes above this critical value readily induce arcing and macroparticle ejection during sputtering. Inclusions below this critical size do not cause arcing or macroparticle ejection. High-speed videos were used to study the arc initiation and behavior. The effect of inclusion aspect ratio and inclusion material type such as SiO@sub 2@, TiO@sub 2@, Al@sub 2@O@sub 3@, CaO, Ta@sub 2@O@sub 5@, AlN and BN on the arcing behavior of aluminum targets were also studied. When the inclusion size exceeds the critical value the sheath over the inclusion is deformed by the charge accumulating on the dielectric inclusion and the plasma positive column distorts toward the target leading to a bipolar arc. Inclusions below the critical size do not distort the sheath to an extent great enough to permit bipolar arc formation. Our proposed model predicts that the critical inclusion size depends upon the sheath thickness, which ranged between 300 and 600 µm for the experimental conditions used in this study.