Fabrication of Photonic Crystal Heterostructures Free of Interface Imperfection Based on Plasma Assisted Versatile Deposition Zahra Sadat Azizi 1(&) , Mohammad Mehdi Tehranchi 2 , and Saeed Pourmahdian 1,3 1 Laser and Plasma Research Institute, G. C., Tehran, Iran Zahra.s.azizi@gmail.com 2 Department of Physics, Shahid Beheshti University, Tehran, Iran 3 Polymer Engineering Department, Amirkabir University of Technology, Tehran, Iran Abstract. In this study, we proposed a facile one-step thermal self-assemble method for depositing a photonic crystal heterostructure (PCH) on a flexible polymer substrate which can filter a determined wavelength band from a broad spectrum illumination and provide transmission of an adjustable wavelength. Method includes improving surface hydrophilicity property of the polymer sub- strates using the application of cold plasma treatment and using one-step thermal treatment for deposition of PCH. The plasma treatment successfully increased the hydrophilicity of the surface of the heat-sensitive polymer substrates. The device resulting from the method has defect-free junction structure that contains at least two photonic crystals with different photonic crystal lattice constants. The PCHs led to a broadband reflection as well as creating low-loss waveguides, high- performance filters, frequency selectors, and chemo/biosensors. Keywords: Colloidal deposition Á Flexible substrate Á Interface imperfection Á Photonic crystal Á Plasma treatment 1 Introduction Over the past several decades, a number of methods have been used to fabricate photonic crystals (PCs) composed of monodisperse spheres [1, 2]. However, these PCs are in limited use because of the only one transmission peak for the PCs. In order to resolve this problem, complex PCs such as formed PC heterostructures and embedded artificial defects are designed for modulation of light [3]. Currently, most of these crystal films have been prepared by an evaporation process, which results in increased manufacturing time [4]. The crystals may be rapidly prepared, but it is dif ficult to manipulating thick crystal with high reflectance and there is not any way to adjust lattice constant to have various reflection colors using one size particles. © Springer Nature Switzerland AG 2020 H. Mirzadeh and A. A. Katbab (Eds.): ISPST 2018, Eco-friendly and Smart Polymer Systems, pp. 602–605, 2020. https://doi.org/10.1007/978-3-030-45085-4_145