扩散、合并和粗化:沉积在液体基底表面Ag原子团簇及薄膜的演变过程  

Diffusion,Coalescence and Coarsening:Evolution of Silver Clusters and Thin Films Deposited on a Liquid Surface

作　　者：杨波[1] 金进生[1] 焦正宽[1] 叶高翔[1] 

机构地区：[1]浙江大学物理系,杭州310028

出　　处：《真空科学与技术》2002年第3期193-197,共5页Vacuum Science and Technology

基　　金：国家自然科学基金资助项目 (No .198740 16);浙江省青年人才专项基金资助项目 (No .1997 RC960 3 )

摘　　要：研究了沉积在液体基底表面的Ag原子团簇的扩散、合并和粗化机制。对薄膜生长过程的原位观察结果表明 :沉积在硅油表面的Ag原子首先凝聚成具有网状结构的薄膜 ;然后薄膜破裂成分枝状的碎片 ,并逐渐凝聚成准圆形团簇 ;通过扩散和合并 ,准圆形团簇的尺寸随时间而增大 ,其数密度随时间而减小。研究发现 ,准圆形团簇对的扩散系数D和团簇对的总面积S0 满足指数关系D∝S-α0 ,其中指数α =0 5 4± 0 0 8。此外 ,还对Ag原子准圆形团簇的相对尺寸分布函数及凝聚速率做了详细研究。The diffusion, coalescence and coarsening characteristics of silver clusters grown on liquid substrates are systematically studied. Silver clusters and thin films are observed in situ. The results indicate that the silver atoms form a characteristic network-shaped silver film on the silicon oil surface first. Then the film breaks into ramified fragments, which finally form compact clusters. The compact clusters diffuse and coalescence on the silicon oil surface and their size increases where as their cluster density decreases with time. Our results show that the diffusion coefficient of the cluster pair, ie, D, depends on the size of the cluster pair, S0, as D ∝ S0-α, where α =0.54±0.08. The size distribution of the compact cluster and the aggregation rate are also studied.

关 键 词：演变过程 液体基底 薄膜 扩散 合并 粗化 表面沉积 银原子团簇 

分 类 号：O484[理学—固体物理]