Improved resistance to electromigration and acoustomigration of Al interdigital transducers by Ni underlayer  

作　　者：Qi Li Su-Lei Fu Cheng Song Guang-Yue Wang Fei Zeng Feng Pan 

机构地区：[1]Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China

出　　处：《Rare Metals》2018年第10期823-830,共8页稀有金属（英文版）

基　　金：financially supported by the National Key Research and Development Program of China(No. 2016YFB0402700);Beijing Science and Technology Project (No. D171100004617001).

摘　　要：The structure and morphology of A1 interdigital transducers as a function of Ni underlayer thickness were studied. The A1 （111） texture intensity increases first and then decreases as Ni underlayer thickness increases. 6-nm Ni underlayer results in the strongest A1 （111） texture with flattest surface, which exhibits almost 10 times longer life in electromigration measurement than those without Ni underlayer. 1.5 GHz surface acoustic wave filters fabri- cated with A1 film on 6-nm Ni underlayer also have improved power durability compared with those without Ni underlayer from 29.0 to 32.5 dBm. It is observed that those fine grains in the 6-nm Ni underlayer greatly enhance A1 （111） texture. Together with increased adhesion force, strong A1 （111） texture accounts for the improved resistance to electromigration and acoustomigration via the reduction of gains boundaries, resistivity, and fine grains at the interface, which is promising for high power surface acoustic wave filters.The structure and morphology of A1 interdigital transducers as a function of Ni underlayer thickness were studied. The A1 （111） texture intensity increases first and then decreases as Ni underlayer thickness increases. 6-nm Ni underlayer results in the strongest A1 （111） texture with flattest surface, which exhibits almost 10 times longer life in electromigration measurement than those without Ni underlayer. 1.5 GHz surface acoustic wave filters fabri- cated with A1 film on 6-nm Ni underlayer also have improved power durability compared with those without Ni underlayer from 29.0 to 32.5 dBm. It is observed that those fine grains in the 6-nm Ni underlayer greatly enhance A1 （111） texture. Together with increased adhesion force, strong A1 （111） texture accounts for the improved resistance to electromigration and acoustomigration via the reduction of gains boundaries, resistivity, and fine grains at the interface, which is promising for high power surface acoustic wave filters.

关 键 词：A1 （111） texture Ni underlayer ELECTROMIGRATION Power durability Surface acoustic wave filters 

分 类 号：TN713[电子电信—电路与系统]