Effect of Electroless Nickel Alloy Films as Intermediate layer on Au/Ni-P Films
Today is an information technology age, downsizing for printed circuit board has been strongly required. Usage of electroless plating method instead of electro-plating is one of the promising candidates for downsizing by eliminating lead wiring. An electroless Au film deposited on an electroless Ni-P film system has been commonly used. However, the electroless Au plating baths are displacement-type solution, a local corrosion of electroless Ni-P is occurred. The local corrosion deteriorates adhesion strength between Au and Ni-P films. To prevent local corrosion, a Pd intermediate layer was proposed and put it practical usage. Since the palladium is expensive and its price is not stable, other intermediate layer has been actively investigated from the view-point of cost reduction. In this paper, we propose electoroless Ni-W-P and Ni-Mo-P alloy films because codeposition of refractory metal improve properties of Ni-P films from our previous investigations. For the intermediate layer, high heat-resistance properties are necessary, the ternary alloy film showed high heat-resistance. New intermediate layers was evaluated by mainly wire-bonding strength,. The new intermediate layers show almost the same properties of the Pd intermediate layer and lamination, because the ternary Ni alloy films suppress local corrosion and Ni diffusion to the Au surface as same as the that of Pd intermediate layer.
Ichiro Koiwa Yohei Wakuta Takeshi Muramatsu Hideto Watanabe Hideo Honma
Kanto Gakuin University,Kojima Chemicals Co.Ltd.1-50-1,Mutsuurahigashi,Kanazawa-ku,Yokohama-shi,Kanagawa 236-8501,Japan;337-26 Kasiwabara,Sayama-shi,Saitama 350-1335,Japan
国际会议
上海
英文
2008-03-17（万方平台首次上网日期，不代表论文的发表时间）