An innovative approach to photolithography for optical recording of high-resolution two-dimensional structures in a negative SU8 photoresist by activation of up-conversion luminescence in Yb3+ and Tm

Synthesis of NaYF4:Yb3+, Tm3+ Nanocrystals Via the Thermal Decomposition Method Using Refined Sunflower Oil

“…This means that there are fewer nanoparticles which can emit UC luminesce. (2) In this study, the mean size of synthesized nanoparticles is 17.2 ± 3.0 nm, while in [27] the mean size of nanoparticles is 33.9 ± 4.6 nm. Smaller nanoparticle size means that energy transfer steps from Yb 3+ to Tm 3+ are less likely to occur.…”

“…For comparison, Fig. 3 also shows UC luminescence spectra (red line) for NaYF 4 core / shell nanoparticles doped with Yb 3+ , Tm 3+ which are synthesized with typical synthesis method [27]. It is possible to observe differences in the ratios of the different UC luminescence bands and in the overall UC luminescence intensity.…”

Thermal Effects in Up-Conversion Luminescence NaYF4: Tm3+, Yb3+ Core-Shell Nanoparticles in the Temperature Range of 18–312 K

“…This study has shown how these hexagonal NaYF 4 core-shell structured nanoparticles are used for the photolithography process. 11 Morphology of β-NaYF 4 core-shell structured nanoparticles (Figure 1) was analyzed using the scanning electron microscope Helios UX 5 (Thermo Scientific) in scanning transmission electron microscope (STEM) mode. Hexagonally shaped structures are observed in the STEM images as expected, since NaYF 4 belongs to P 6 false¯ space group (hexagonal system).…”

“…[8][9][10] Such material could be used for various applications, e.g., photolithography. 11 UC luminescence closely depends on the temperature. Therefore, in order to understand the potential use of UC luminescence in materials under different conditions, including different temperatures, it is necessary to study the nature of these temperature dependencies experimentally.…”