退火气氛与扩散阻挡层对Cu膜表面完整性的影响  

Influence of Annealing Environment and Diffusion Barrier on Surface Topography of Copper Films

作　　者：宋忠孝[1] 徐可为[1] 陈华[1] 

机构地区：[1]西安交通大学金属材料强度国家重点实验室,西安710049

出　　处：《真空科学与技术》2003年第3期165-168,共4页Vacuum Science and Technology

基　　金：国家自然科学基金重点项目 (No 5 993 10 10 );教育部骨干教师计划项目

摘　　要：用反应磁控溅射和离子束辅助沉积 (IBAD)方法分别在 ( 111)单晶硅基体上沉积了Cu/ZrSiN与Cu/ZrN膜系 ,制得的试样在 80 0℃下分别在真空和N2 、H2 混合气体两种气氛中退火 1h ,结果表明 ,在真空中退火的Cu/ZrSiN膜由于ZrSiN膜裂纹导致Cu膜裂纹的产生 ;ZrSiN和ZrN扩散阻挡层上的Cu膜还有很多由晶界迁移导致的孔洞。在氮氢混合气体中退火时ZrSiN扩散阻挡层上的Cu膜由于具有高的应力而发生断裂 ,ZrN扩散阻挡层上的Cu膜则没有这一现象。在N2 、H2 混合气体中退火时Cu由于还原性气氛抑制了晶界迁移而使Cu膜的孔洞变小。Cu/ZrSiN and Cu/ZrN films were grown on Si (111) substrates by reactive magnetron sputtering and ion beam auxiliary deposition. respectively. After annealing at 800°C in low vacuum(2 ×10-3 Pa) or in a mixture of hydrogen (10%) and nitrogen (90%) for 1 h, the surface topography of the Cu films was studied with scanning electron microscopy. The results show that surface cracks of the ZrSiN diffusion barrier layers propagate through the Cu layers and a large number of irregularly shaped voids emerge on Cu layers grown both on ZrSiN and ZrN diffusion barrier layers because of the coalescence of Cu atoms. After annealing in a H2/N2 mixture. the number and size of the void decrease but the fairly high stresses in Cu/ZrSiN multilayers generate many small cracks on the Cu surface. As for the Cu layers grown on ZrN diffusion barrier layers, no crack was observed due to the lower stress in Cu/ZrN system. It was found that reduction of hydrogen would adversely affect the void formation.

关 键 词：ZrSiN ZRN 扩散阻挡层 CU膜 表面完整性 

分 类 号：TN305.93[电子电信—物理电子学]