生长初期Ta膜的表面动态演化行为  

Surface dynamic evolution of Ta film growth in the initial stage

作　　者：杨吉军[1] 徐可为[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：《物理学报》2007年第10期6023-6027,共5页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(973)项目(批准号:2004CB619302);国家自然科学基金(批准号:50471035)资助的课题~~

摘　　要：用磁控溅射方法在单晶Si衬底上沉积膜厚为15—250nm的Ta膜.基于原子力显微镜获得的薄膜表面形貌,用动力学标度理论量化表征薄膜表面动态演化行为.结果表明:当膜厚d<50nm时,薄膜生长指数β≈0.17,而d>50nm后β≈0.45;随着d增加,粗糙度指数α由0.24逐渐增加到0.69,且在d>50nm后趋于稳定.Ta膜的表面动态演化行为揭示了其由小岛聚合结构向连续膜演化的生长过程.与自阴影等非局域效应引起的非稳定行为不同的是,当d<50nm时,薄膜表面动态演化的非稳定行为来源于生长初期的小岛聚合,表面小岛沿膜面切向的生长优于沿法向的生长.随着d继续增加,薄膜以连续膜形式生长,表面动态演化趋于稳定.Tantalum thin films with thicknesses varying from 15 to 250 nm were grown on silicon substrates by magnetron sputtering. Surface morphology of the films was investigated by atomic force microscopy. Then the film surface dynamic evolution was analyzed within the framework of dynamic sealing theory. The results show that the growth exponent β is about 0. 17 for the films thinner than 50 nm and 0.45 for thicker films. With the increase of film thickness, the roughness exponent a increases from 0.24 to 0.69 and remains constant for the films thicker than 50 nm. The dynamic surface evolution reveals the growth transition from island coalescence to bulk film growth. Surface islands prefer lateral growth to vertical growth during island coalescence.

关 键 词：薄膜 表面形貌 生长 动力学标度 

分 类 号：O484.1[理学—固体物理]