Publisher : The Korean Microelectronics and Packaging Society
DOI : 10.6117/kmeps.2015.22.3.019
Title & Authors
Effects of Sputtering Conditions of TiW Under Bump Metallurgy on Adhesion Strength of Au Bump Formed on Al and SiN Films Jo, Yang-Geun; Lee, Sang-Hee; Kim, Ji-Mook; Kim, Hyun-Sik; Chang, Ho-Jung;
In this study, two types of Au/TiW bump samples were fabricated by the electroplating process onto Al/Si and SiN/Si wafers for the COG (Chip On Glass) packaging. TiW was used as the UBM (Under Bump Metallurgy) material of the Au bump and it was deposited by a sputtering method under the sputtering powers ranges from 500 to 5000 Watt. We investigated the delamination phenomenas for the prepared samples as a function of the input sputtering powers. The stable interfacial adhesion condition was found to be 1500 Watt in sputtering power. In addition, the SAICAS (Surface And Interfacial Cutting Analysis System) measurement was used to find the adhesion strength of Au bumps for the prepared samples. TiW UBM films were deposited at the 1500 Watt sputtering power. As a results, there was a similar adhesion strengths between TiW/Au interfacial films on Al/Si and SiN/Si wafers. However, the adhesion strength of TiW UBM sputtering films on Al and SiN under films were 2.2 times differences, indicating 0.475 kN/m for Al/Si wafer and 0.093 kN/m for SiN/Si wafer, respectively.
Au Bump;Chip on Glass (COG);Packaging;Under Bump Metallurgy (UBM);Adhesion Strength;SAICAS (Surface And Interfacial Cutting Analysis System);
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