title: Site-selective assembly of quantum dots on patterned self-assembled monolayers fabricated by laser direct-writing.
abstract: A simple and efficient route for quantum dot (QDs) patterning using self-assembled monolayers (SAMs) as templates is described. By means of a laser direct-writing (LDW) technique, SAMs of octadecylphosphonic acid formed by adsorption on native oxide layer of titanium film were patterned through laser-induced ablation of the SAM molecules. This technique allows the creation of chemical-specific patterns accompanied by slight change in the topography. Using atomic force microscopy and friction force microscopy, the dependence of feature size and characteristics on the irradiation dose was demonstrated. Upon immersion of a substrate with patterned SAMs bearing thiol as the terminal group into a dispersion of QDs resulted in the assembly of QDs on the specific thiol-terminated areas. Patterns of QDs with different photoluminescent wavelength were generated. The LDW technique, which is convenient and flexible due to its path-directed and maskless fabrication process, provided a new powerful approach for patterning materials on surfaces for various applications.
authors.affiliation: National Center for Nanoscience and Technology, Graduate School of Chinese Academy of Sciences, 11 Beiyitiao, Zhongguancun, Beijing, People's Republic of China.
authors.forename: Chong
authors.initials: C
authors.lastname: Wu
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Wang
authors.forename: Xuemingyue
authors.initials: X
authors.lastname: Han
authors.forename: Xinming
authors.initials: X
authors.lastname: Hu
authors.forename: Qianyi
authors.initials: Q
authors.lastname: Cheng
authors.forename: Baohang
authors.initials: B
authors.lastname: Han
authors.forename: Qian
authors.initials: Q
authors.lastname: Liu
authors.forename: Tianling
authors.initials: T
authors.lastname: Ren
authors.forename: Yonghong
authors.initials: Y
authors.lastname: He
authors.forename: Shuqing
authors.initials: S
authors.lastname: Sun
authors.forename: Hui
authors.initials: H
authors.lastname: Ma
mesh_terms: D003460:Crystallization / Q000379:methods*; D007834:Lasers; D046911:Macromolecular Substances / Q000737:chemistry / Q000528:radiation effects; D008422:Materials Testing; D008968:Molecular Conformation / Q000528:radiation effects; D054802:Molecular Imprinting / Q000379:methods*; D045663:Quantum Dots; D013499:Surface Properties / Q000528:radiation effects
chemical_list: D046911:Macromolecular Substances