Cu互连Mo基新型扩散阻挡层的化学机械抛光  

Study on CMP of Copper Interconnect with Novel Mo-Based Diffusion Barriers

作　　者：王永伟[1] 王敬轩[1] 屈新萍[1] 

机构地区：[1]复旦大学微电子学系,上海200433

出　　处：《半导体技术》2012年第11期846-849,共4页Semiconductor Technology

基　　金：国家科技重大专项(2009ZXO2308-005)

摘　　要：亚16 nm以下的互连技术中需要采用电阻率低、阻挡性能好、与Cu粘附性好并同时具有较好抛光性能的新型扩散阻挡层。利用自制2英寸图形片,对Mo和CoMo新型扩散阻挡层Cu互连结构图形片的抛光性能进行了初步研究。使用扫描电子显微镜、原子力显微镜及白光干涉仪观察表面与截面微观形貌;用电阻测试研究抛光后各不同区域铜线深度变化。结果显示,经过相同的酸性抛光液(pH值为4)抛光后,相比于Mo样品,CoMo样品具有较小的Cu碟形缺陷和较小的表面粗糙度。抛光后CoMo样品具有良好的抛光表面均匀性。A novel diffusion barrier with low resistivity,good diffusion properties and polishing properties is urgently needed in the sub-16 nm interconnect technology.The chemical mechanical polishing（CMP）performance of copper interconnect structures with Mo and CoMo as novel barriers were discussed.Scanning electron microscopy（SEM）,atomic force microscopy（AFM）and white light interference profiler were used to observe the surface and cross-section morphology for the polished Cu patterns.The resistance tests were used to compare the copper depths after CMP among different regions.The results indicate that the sample with CoMo alloy as the barrier has less copper dishing defects and surface roughness compared to the other kind of sample with Mo as the barrier after CMP with the copper CMP slurry（pH value is 4）.The polished surface of CoMo sample has good uniformity.

关 键 词：化学机械抛光 铜互连 扩散阻挡层 钴钼合金 碟形缺陷 

分 类 号：TN305.2[电子电信—物理电子学]