Modification of Ta/polymeric low-k interface by electron beam treatment
Mhaisalkar, Subodh Gautam
Date of Issue2006
School of Materials Science and Engineering
Polymeric dielectric, porous polyarylene ether (PAE), was introduced in the Cu damascene structures because of its low dielectric constant to reduce resistance-capacitance (RC) delay. One of the requirements of a low-k material includes its good adhesion to the other interconnect materials. In the present study, the adhesion energy (Gc) of the barrier layer Ta/PAE interface was quantitatively measured by a four-point bending technique. The obtained Gc value of the pristine Ta/PAE interface was 5.9 ± 1.1 J/m2. If the PAE was subjected to electron-beam (EB) treatment with low dose (20 μC/cm2) prior to Ta deposition, Gc value increased to 8.1 ± 0.5 J/m2. However, with high-dose (40 μC/cm2) EB treatment, Gc value reduced to 4.0 ± 0.6 J/m2. The adhesion improvement and degradation induced by low- and high-dose EB were correlated to the increase and reduction of the amount of C–Ta bonds at the Ta/PAE interface, respectively. The phenomena were further studied by X-ray photoelectron spectroscopy analysis.
Journal of the electrochemical society
© 2006 The Electrochemical Society. This paper was published in Journal of The Electrochemical Society and is made available as an electronic reprint (preprint) with permission of The Electrochemical Society. The paper can be found at the following DOI: http://dx.doi.org/10.1149/1.2129493. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.