离子注入的铝在Si(100)表面的偏析及其引起的纳米团簇和合金晶粒形成现象的实验研究  

Experimental investigation on formation of Al-Si clusters and nanocrystals in the segregation of ion-implanted Al on Si(100)

作　　者：高皓[1] 廖龙忠[1] 张朝晖[1] 

机构地区：[1]北京大学物理学院,人工微结构与介观物理国家重点实验室,北京100871

出　　处：《物理学报》2009年第1期427-431,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号90406007,10434010)资助的课题~~

摘　　要：通过高温退火注入了铝的Si(100)样品,探讨偏析出来的铝在硅表面的热力学行为.由900℃的退火实验发现,偏析出来的铝原子一方面形成Si(100)基底的外延铝膜和铝岛,另一方面与硅原子结合形成尺度约为2—3nm的铝硅团簇.而1200℃的退火实验显示,铝和硅的快速冷凝形成了立方晶系的Al4Si合金晶粒、尺度约为20—30nm.细小的铝硅团簇在结构上独立于样品基底并且趋于聚集成团,很可能是在高温退火和快速降温过程中形成铝硅合金晶粒的前驱.By high-temperature annealing of Si（100） samples containing ion-implanted Al atoms,thermodynamic behaviors of the segregated Al atoms on the surfaces have been investigated.Experiments of annealing the samples at 900℃ show that Al and Si atoms conbine to form Al-Si clusters with size of 2—3nm,while segregated Al atoms form epitaxial Al film and islands on Si（100） surfaces.Further annealing at 1200℃ indicates that rapid cooling of samples leads to formation of cubic Al_4Si grains of 20—30nm size.The Al-Si clusters seem to be independent of the substrate structure and tend to come together,which are probably the precursor of the Al-Si alloy formed in the process of the high-temperature annealing and rapid cooling.

关 键 词：硅表面 铝掺杂 团簇 Al4Si 

分 类 号：O482[理学—固体物理]