3D电子封装侧壁布线的互连界面处理工艺研究  

Surface Treatment for 3D Packaging Sidewall Interconnect

作　　者：杨繁 吴蕴雯 高立明[1] 张文龙[1] 李明[1] YANG Fan;WU Yunwen;GAO Liming;ZHANG Wenlong;LI Ming(School of Material Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学材料科学与工程学院,上海200240

出　　处：《电镀与精饰》2022年第9期1-8,共8页Plating & Finishing

基　　金：国家自然科学基金(61774105)。

摘　　要：与传统封装形式相比,3D电子封装可实现更高密度集成,大幅缩小尺寸。以侧壁布线为互连方式的3D封装结构更加紧凑,与现有工艺兼容性好,具有广泛的应用前景。本研究针对该工艺缺乏合适的侧壁处理手段导致互连界面电阻偏高的问题,探讨了离子轰击等物理方法对侧壁互连界面处理的工艺,实现了低接触电阻侧壁互连。同时,借助高分辨透射电镜、小角度X射线衍射及纳米束电子衍射等分析手段对侧壁互连界面层进行了解析。结果表明,处理后界面氧化膜中氧原子含量大幅降低,并密集分布着被还原的金属铜晶粒,证明了即使氧离子轰击也可使氧化膜中的铜离子被还原为金属铜,从而揭示了离子轰击降低互连界面接触电阻的内在机制。Comparing to traditional packaging technology,3D packaging can achieve higher integration density and thus reduce device size.3D stacking with sidewall interconnect is a promising approach.It has compact structure and good integration with standard technologies.But it lacks a suitable cleaning process for sidewall surfaces,which leads to the problem of high interconnection interface resistance.To address this issue,this study develops an ion bombardment treatment for sidewall interconnects.The treatment resulted in minimal contact resistance.The contact interface was characterized through transmission microscope,glancing angle X-ray diffraction and nano-beam electron diffraction.The results showed that oxygen atomic fraction in the interface was reduced and metallic Cu grains densely distributed inside the oxide layer after the treatment.The results suggest that Cu oxides were reduced during the treatment and the reduction mechanism works even when the working gas being oxygen.This study reveals the key mechanism for ion bombardment lowering contact resistance.

关 键 词：3D电子封装 侧壁布线 互连界面 等离子体处理 

分 类 号：TN305.2[电子电信—物理电子学]