생산기술특허연구회

in this work, a study for the ubm(under bump metallurgy) x-layer formation on the aluminium-based circuits focused on the zincation process has been performed. to make the oxidized surface of aluminium pads conductive, the zincation pretreatment process has extensively been used for ubm x-layers, which commonly consists of gold/nickel/zinc deposits. l)2) the procedure of ubm x-layer formation involves alkaline surface cleaning, surface activation by zincation, electroless nickel plating and immersion gold plating. the pb-free tin alloy deposition as like sn-cu, sn-ag or sn-bi has been applied to build a solder bump on ubm x-layers. a rough and thin zinc film was formed on the surface of aluminium substrates after the first zincating process. the second zincating process provides an improved surface morpology with fine zinc grains. for this application, zincating processes are significant steps for the following electroless deposition, which largely depends on the morpology of zincate treated aluminium surface. the atomic force microscopy(afm) and fleld emission scanning electron microscopy(fe-sem) were used to analysis the surface roughness and morpology of deposits at each deposition step. the elemental analysis using energy disperse x-ray(eds) and glow discharge optical emission spectrometer(gd-oes), and micro-crosssectional analysis using focus ion beam(fib) were also conducted. 더 자세한 내용은 첨부파일 참조