论文部分内容阅读
采用脉冲激光沉积技术制备了钴纳米薄膜,分析和讨论了不同背景气压和脉冲频率对钴纳米薄膜表面形貌的影响及纳米微粒的形成机理。实验结果表明:在低背景气压下,等离子体羽辉自身粒子之间的碰撞占主导作用,容易形成液滴;在较高背景气压下,等离子体羽辉边缘粒子和背景气体粒子之间的碰撞占主导作用,容易形成小岛并凝聚成微颗粒;在4Hz的脉冲重复频率和5Pa背景气压下生长出单分散性良好的钴纳米颗粒。
The cobalt nanofilms were prepared by pulsed laser deposition technique. The influence of different background pressure and pulse frequency on the surface morphology of nanocrystalline cobalt nanofilms and the formation mechanism of nanoparticles were analyzed and discussed. The experimental results show that at low background pressure, the collisions between the plasma plume’s own particles play a leading role and the droplets are easy to form. Under the high background pressure, the collisions between the plasma plume’s edge particles and the background gas particles Dominated the formation of islets and coalesced into micro-particles. Cobalt nanoparticles with good monodispersion were grown at a pulse repetition frequency of 4 Hz and a background pressure of 5 Pa.