The laser ablation threshold of YBa2Cu3O6+x as revealed by using projection optics
The laser ablation threshold of YBa2Cu3O6+x as revealed by using projection optics
复制标题
使用投影光学显示 YBa2Cu3O6 x 的激光烧蚀阈值
DOI：
10.1016/0169-4332(94)00372-6
复制
发表时间：
1995
影响因子：
6.7
通讯作者：
R. Griessen
中科院分区：
文献类型：
--
作者：
B. Dam;J. Rector;M. Chang;S. Kars;D. G. Groot;R. Griessen
投影光学系统是一种减少激光烧蚀过程中目标上的空间能量密度变化的手段。利用投影光学系统研究了248 nm准分子激光与YBa_2Cu_3O_（6 + x）靶的相互作用，得到了1.0 J/cm ~ 2的阈值能量密度。低于该阈值，非化学计量烧蚀导致目标形态的显著变化和烧蚀速率的衰减。在该阈值以上，靶的化学计量是保守的。沉积膜的粗糙度随着靶的粗糙度的增加而沿着增加。因此，很明显，为了获得平坦的化学计量薄膜，应该使用刚好高于阈值的窄注量窗口。
Projection optics is a means to reduce the spatial energy density variations on the target during laser ablation. Using projection optics to study the interaction between a spatially uniform 248 nm excimer laser beam and a YBa2Cu3O6+xtarget we observe a well-defined threshold fluence of 1.0 J/cm2. Below this threshold non-stoichiometric ablation results in an dramatic change in target morphology and in a decay of the ablation rate. Above this threshold the stoichiometry of the target is conserved. The roughness of the deposited films increases along with the increase in roughness of the target above the threshold. Thus it is clear that in order to obtain flat stoichiometric films one should use a narrow fluence window just above the threshold.