Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO, 65211, USA.
Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA.
Small. 2017 May;13(18). doi: 10.1002/smll.201604197. Epub 2017 Mar 15.
A continuing trend of miniaturized and flexible electronics/optoelectronic calls for novel device architectures made by compatible fabrication techniques. However, traditional layer-to-layer structures cannot satisfy such a need. Herein, a novel monolithic optoelectronic device fabricated by a mask-free laser direct writing method is demonstrated in which in situ laser induced graphene-like materials are employed as lateral electrodes for flexible ZnS/SnO ultraviolet photodetectors. Specifically, a ZnS/SnO thin film comprised of heterogeneous ZnS/SnO nanoparticles is first coated on polyimide (PI) sheets by a solution process. Then, CO laser irradiation ablates designed areas of the ZnS/SnO thin film and converts the underneath PI into highly conductive graphene as the lateral electrodes for the monolithic photodetectors. This in situ growth method provides good interfaces between the graphene electrodes and the semiconducting ZnS/SnO resulting in high optoelectronic performance. The lateral electrode structure reduces total thickness of the devices, thus minimizing the strain and improving flexibility of the photodetectors. The demonstrated lithography-free monolithic fabrication is a simple and cost-effective method, showing a great potential for developement into roll-to-roll manufacturing of flexible electronics.
不断发展的小型化和柔性电子/光电技术需要采用兼容的制造技术来实现新型器件结构。然而，传统的层层结构无法满足这一需求。在此，我们展示了一种通过无掩模激光直写方法制造的新型单片光电设备，其中原位激光诱导类石墨烯材料被用作柔性 ZnS/SnO 紫外光探测器的横向电极。具体来说，首先通过溶液工艺在聚酰亚胺（PI）片上涂覆包含异质 ZnS/SnO 纳米颗粒的 ZnS/SnO 薄膜。然后，CO 激光辐照烧蚀 ZnS/SnO 薄膜的设计区域，并将下方的 PI 转化为高导电性的石墨烯，作为单片光电探测器的横向电极。这种原位生长方法在石墨烯电极和半导体 ZnS/SnO 之间提供了良好的界面，从而实现了高性能的光电性能。横向电极结构减少了器件的总厚度，从而最小化了应变并提高了探测器的灵活性。所展示的无光刻单片制造是一种简单且具有成本效益的方法，为柔性电子产品的卷对卷制造开辟了广阔的前景。
