Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
ACS Nano. 2011 Sep 27;5(9):7010-9. doi: 10.1021/nn201588p. Epub 2011 Aug 8.
We investigated how pulsed laser annealing can be applied to process thin films of colloidal nanocrystals (NCs) into interconnected nanostructures. We illustrate the relationship between incident laser fluence and changes in morphology of PbSe NC films relative to bulk-like PbSe films. We found that laser pulse fluences in the range of 30 to 200 mJ/cm(2) create a processing window of opportunity where the NC film morphology goes through interesting transformations without large-scale coalescence of the NCs. NC coalescence can be mitigated by depositing a thin film of amorphous silicon (a-Si) on the NC film. Remarkably, pulsed laser annealing of the a-Si/PbSe NC films crystallized the silicon while NC morphology and translational order of the NC film are preserved.
我们研究了如何将脉冲激光退火应用于胶体纳米晶体（NCs）薄膜，将其加工成互联的纳米结构。我们说明了入射激光能量与 PbSe NC 薄膜相对于块状 PbSe 薄膜的形态变化之间的关系。我们发现，激光脉冲能量在 30 至 200 mJ/cm(2) 的范围内产生了一个加工窗口，在这个窗口中，NC 薄膜的形态会发生有趣的变化，而 NC 不会发生大规模的聚集。通过在 NC 薄膜上沉积一层非晶硅（a-Si），可以减轻 NC 聚集。值得注意的是，对 a-Si/PbSe NC 薄膜进行脉冲激光退火，使硅结晶，同时保持 NC 形态和 NC 薄膜的平移有序。
