臺灣博碩士論文加值系統

本研究主要目的在探討以Al/Mo/Ni作為矽晶/焊錫隆點間金屬化層的可行
性。實驗以濺鍍法濺鍍Al，Mo，Ni或Pd金屬層，並於矽晶片上製作多層膜
Al/Mo/Ni或Al/Mo/Pd，以波焊法被覆鉛錫合金於此多層膜。內容包括Al/
Mo/Ni性質的探討及焊錫隆點之製作。並探討鍍層厚度對Al/Mo/Ni之附著
性及熱處理條件下材料相互作用之影響。焊錫隆點之製作主要改變波焊之
溫度與速度，以觀察鉛錫隆點表面之附著型態。實驗結果顯示，在Si/Al/
Mo上濺鍍不同厚度的鎳鍍層時，鎳鍍層愈厚，多層膜Si/Al/Mo/Ni之附著
性會呈下降的趨勢。濺鍍Al，Mo，Ni薄膜時，鎳靶材濺射速率非常慢約
為1.4*/sec。以Si/Al/Mo/Ni之試片被覆鉛錫合金，波焊之輸送帶速度愈
快，鉛錫合金表面附著情形愈差。將焊錫隆點被覆鉛錫合金時，在相同之
波焊條件下，只在局部區域有鉛錫合金鍍著，鉛錫合金無法完整的被覆在
隆點位置上。以Pd代替Ni潤濕層，多層膜Si/Al/Mo/Ni之試片以相同波焊
條件被覆焊錫，輸送帶速度0.5m/min，焊錫有可能被覆於Pd位置上。輸送
帶速度1.5m/min時鉛錫合金無法完整被覆於隆點，輸送帶速度比 1.5m/
min快或慢製作之焊錫隆點均可能會有曳尾及搭橋之情形發生。Al/
Mo(3000*)/Ni/Pb-Sn試片經150℃不同時間熱處理，鋁在600小時熱處理後
，部份的鋁元素往矽基材方向擴散，經過900小時之熱處理後，鋁元素則
穿過鉬層往鉛錫方向擴散。6000*之鉬在600小時熱處理能有效的阻止錫與
鋁的擴散，鎳在多層膜組合中當作潤濕層，並未發揮擴散障礙層的功效。

The Al/Mo/Ni thin film was investigated for the potential
application as the under bump metallurgy between silicon and
solder. The Al/Mo/Ni thin film were prepared by sputtering. It
was investigated for the effect of Al，Mo，Ni thin film
thickness on the adhesion of Si/Al/Mo/Ni and the effect of wave
soldering parameters on the solder bump morphology. The
experimental results showed that the increase in thickness of Ni
，degraded the adhesion of Si/Al/Mo/Ni. The sputtering rate of
Ni is as low as 1.4*/sec. The increase in conveyor speed during
wave soldering roughened the surface appearance of the solder
on Si/Al/Mo/Ni . It was uneasy to achieve a complete solder
coverage on the bump with Si/Al/Mo/Ni as the under bump
metallurgy. It was find to be able to achieve better bump
structure when Pd was applied replacing Ni. When the conveyor
speed of wave soldering of Si/Al/Mo/Pd is 0.5m/min，the solder
can complete wet on the Pd layer. A conveyor speed as high as
1.5m/min，resulted in incomplete solder coverage. Tailing and
bridging were observed in the solder bump at unsuitable
conveyor speed. Al diffused into the Si substrate when Si/Al/Mo/
Ni/Pb-Sn was heat treated at 150℃for 600 hours，while Al
penetrated through Mo to diffuse into the Pd-Sn deposits after
900 hours of heat treatment. A thickness of 6000* Mo were able
to prevent interdiffusion betwwen Al and Sn at 600 hours of
heat treatment. According to the experimental results，Ni was
not appropriate as a diffusion barrier，intead，it acts as a
wetting layer.