About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Publication
ECS Transactions
Conference paper
X-ray characterization of PEALD versus PVD tantalum nitride barrier deposition and the impact on via contact resistance
Abstract
Plasma enhanced atomic layer deposition (PEALD) of TaN demonstrated the significant benefit of lowering via resistance in back-end-of-line (BEOL) dual damascene copper interconnects with a line width of 32 nm, although PEALD TaN possessed a much higher intrinsic resistivity, approximately 2000 μΩ-cm, compared to physical vapor deposition (PVD) of Ta-rich TaN with a value around 250 μΩ-cm. The mechanism of lowering via resistance was studied by X-ray characterization techniques such as X-ray fluorescence (XRF) and X-ray reflectivity (XRR). XRF analysis indicated the nucleation rate of PEALD TaN is higher on a metal surface compared to a dielectric surface. XRR analysis revealed a smoother and damage free surface between PEALD TaN and silicon oxide, while a rougher interface was formed between PVD TaN and silicon oxide. Via resistance reduction with PEALD TaN is suggested to be related to reduced physical damage at the via bottom. © The Electrochemical Society.