Mistrik Jan, Krbal Milos, Prokop Vit, Prikryl Jan
Center of Materials and Nanotechnologies, Faculty of Chemical-technology, University of Pardubice Studentska 95 53210 Pardubice Czech Republic
Institute of Applied Physics and Mathematics, Faculty of Chemical-technology, University of Pardubice Studentska 95 53210 Pardubice Czech Republic.
Nanoscale Adv. 2023 Apr 18;5(11):2911-2920. doi: 10.1039/d3na00111c. eCollection 2023 May 30.
This work deals with an ellipsometric study of magnetron sputtered thin MoS films. The evolution of the UV-VIS-NIR optical properties of as-deposited and subsequently annealed films is thoughtfully investigated, covering amorphous, amorphous relaxed, partially crystallized, and polycrystallized MoS films. The transition from the mixed 1T'@2H local order in the amorphous phase toward the long-range 2H order in the polycrystalline phase is systematically correlated with film optical properties. The early stage of a few-layer 2H ordering toward the 2H bulk-like polycrystalline structure during annealing is evidenced through the energy shift of MoS prominent excitonic peaks. A considerable change in optical response between metallic (amorphous) and semiconducting (polycrystalline) MoS phases is reported and presented in terms of dielectric permittivity and normal reflectance NIR-VIS-UV spectra. Results of light-heat conversion in the NIR therapeutic window show so far uncovered potential of amorphous MoS as an agent for photothermal therapy. Spectroscopic ellipsometry provided sensitive characterization disclosing essential results complementary to other characterization tools. The benefit of these results is expected to be employed in fundamental and application-motivated research, for example, in the field of phase change materials, photothermal cancer therapy, and magneto-optical study of magnetic ordering in metal transition dichalcogenides, among others.
这项工作涉及对磁控溅射MoS薄膜的椭偏研究。深入研究了沉积态及随后退火薄膜的紫外-可见-近红外光学性质的演变，涵盖非晶、非晶弛豫、部分结晶和多晶的MoS薄膜。从非晶相中混合的1T'@2H局部有序向多晶相中长程2H有序的转变与薄膜光学性质系统相关。通过MoS显著激子峰的能量位移证明了退火过程中从几层2H有序向类2H体相多晶结构转变的早期阶段。报道并根据介电常数和近红外-可见-紫外光谱的正常反射率呈现了金属（非晶）和半导体（多晶）MoS相之间光学响应的显著变化。近红外治疗窗口中的光热转换结果显示了非晶MoS作为光热治疗剂迄今未被发现的潜力。椭偏光谱法提供了灵敏的表征，揭示了与其他表征工具互补的重要结果。预计这些结果的益处将应用于基础研究和应用驱动的研究，例如在相变材料、光热癌症治疗以及金属过渡二硫属化物中磁有序的磁光研究等领域。
