Area-Selective Electroless Deposition of Cu for Hybrid Bonding
Area-Selective Electroless Deposition of Cu for Hybrid Bonding
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用于混合键合的区域选择性化学镀铜
DOI：
10.1109/led.2021.3124960
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发表时间：
2021
影响因子：
4.9
通讯作者：
Beyne Eric
中科院分区：
文献类型：
--
作者：
Inoue Fumihiro;Iacovo Serena;El-Mekki Zaid;Kim Soon-Wook;Struyf Herbert;Beyne Eric
这封信介绍了使用区域选择性化学镀铜的Cu-SiCN混合焊盘的形貌控制。Cu的无电沉积允许在混合键合Cu焊盘上获得突起，而无需进一步的抛光优化。化学机械抛光后凹陷的Cu焊盘在无电沉积后变成突起。这表明化学镀Cu膜选择性地沉积在Cu上，而没有沉积在SiCN表面上。在350 °C下退火后观察到无空隙的Cu-Cu键合界面，在界面处具有无电镀Cu层。在1.4节距下获得100%电连接，其中沉积厚度在靶上。
This letter describes the use of area-selective electroless Cu deposition for topography control of Cu-SiCN hybrid bonding pads. The electroless deposition of Cu allows one to obtain protrusions on hybrid bonding Cu pads without further polishing optimization. A recessed Cu pad after chemical mechanical polishing becomes a protrusion after electroless deposition. This indicates that the electroless Cu film was selectively deposited on Cu, without deposition on the SiCN surface. A void-free Cu-Cu bonding interface was observed after annealing at 350 °C with an electroless Cu layer at the interface. 100% electrical connection was obtained at 1.4-pitch where the deposition thickness was on target.