摘要
利用动力学晶格蒙特卡洛方法模拟了Cu薄膜在Cu(100)面上的三维生长过程。模型中考虑了四个动力学过程:原子沉积、增原子迁移、双原子迁移和台阶边缘原子迁移,各动力学过程发生的概率由多体势函数确定。讨论了基底温度、沉积速率及原子覆盖率对Cu原子迁移、成核和表面岛生长等微观生长机制的影响;获得了Cu薄膜的表面形貌图并计算了表面粗糙度。模拟结果表明,随基底温度升高或沉积速率下降,岛的平均尺寸增大,数目减少,形状更加规则。低温时,Cu薄膜表现为分形的离散生长,高温时,Cu原子迁移能力增强形成密集的岛。Cu薄膜表面粗糙度随着基底温度的升高而迅速减小;当基底温度低于某一临界温度时,表面粗糙度随原子覆盖率或沉积速率的增大而增大;当基底温度超过临界温度时,表面粗糙度随原子覆盖率或沉积速率的变化很小,基本趋于稳定。
The Cu thin film growth process on Cu （100） metal substrate is investigated using a threedimensional kinetic lattice Monte Carlo （KLMC） method. Four kinetic processes are included in the proposed model： deposition, adatom diffusion, dimer diffusion and ledge adatom diffusion. The activation energies for these three diffusion events are calculated using the embedded-atom method. The dependence of the Cu thin film growth on process parameters, including substrate temperature, deposition rate and coverage, is discussed using the KLMC model. The results show that, as the substrate temperature increases or the deposition rate decreases,the average size of the islands becomes bigger and the number of the islands decreases. As the temperature is low, the film shows fractal growth at higher temperature,the island becomes compact and more regular in shape. And the higher the temperature,the smaller the Cu thin film surface roughness. When the substrate temperature is lower than the transition temperature, thesurface roughness increases as the deposition rate and （or） the coverage increases. At higher temperature, the surface roughness is almost the same for different deposition rates or the coverage.
出处
《光子学报》
EI
CAS
CSCD
北大核心
2010年第1期62-66,共5页
Acta Photonica Sinica
基金
国家自然科学基金(10825521)资助
关键词
薄膜生长
原子迁移
KLMC模拟
沉积速率
基底温度
原子覆盖率
表面粗糙度
Thin film growth
Surface diffusion
KLMC simulation
Deposition rate
Substrate temperature
Atom coverage
Surface roughness
