Microelements with High Aspect Ratio Prepared by Self-Focusing of Light at UV-Curing

Regularities in the Formation of Microstructural Elements in a Light-Curable Nanocomposite

“…The observed reduction in the transverse dimensions of the microstructural elements when the distance between the elements increases can be related with inhibition of the photopolymerization process by oxygen in air [6,10]. When the distance between the exposure areas increases as a result of an increase in oxygen content in the adjacent areas of the material and its diffusion into the exposure area, the photopolymerization process slows down, and the element is narrowed.…”

“…On the basis of the available perceptions it can be assumed that the degree of photopolymerization in the interstices between the elements can be determined as a superposition of three processes: oxygen inhibition [6,10], shrinkage of light-curable composition [7], and also diffusion of photoradicals that is supposed in the work [12]. In the result of these processes when the distance between the elements reduces, it is probable that more favorable conditions are formed for photopolymerization in the interstices between them -a reduction in oxygen amounts, a reduction in the layer thickness due to shrinkage and, probably, an increase in the concentration of free radicals.…”

“…A large positive changing of the refractive index in the material during photopolymerization process lead to light self-focusing effects and as result to compensation of initial spreading of optical radiation. The regularities of photopolymerization during self-focusing were in most detail studied as applied to the problem of the microelements formation at the optical fiber edge [9,10]. The works [10,11] show that in the result of self-focusing it is possible to obtain structures with a high aspect ratio by using long-wave radiation with high spreading.…”

Subwavelength Microstructures Fabrication by Self‐Organization Processes in Photopolymerizable Nanocomposite

“…Selfwriting and self-focusing effects discussed above are applicable for diminishing polymerized area initially corresponding to light distribution in objective spot as well as to overcome geometric distribution of the light in focus. The main effect is light self-focusing that can be reinforced by oxygen inhibition [14,15] and nanoparticles redistribution at photopolymerization. Figure 5 shows proposed application of self-writing processes in projection photolithography: using nanocomposite with self-writing effects overcoated on photoresist to improve light distribution in the spot on the photoresist surface.…”

Optical Nanocomposites Based on High Nanoparticles Concentration and Its Holographic Application

“…The main effect is light selff o c u s i n g t h a t c a n b e r e i n f o r c e d b y o x y g e n inhibition [22,23] and nanoparticles redistribution at photopolymerization. Figure 16 shows proposed application of selfwriting processes in projection photolithography: using nanocomposite with self-writing effects overcoated on photoresist to improve light distribution in the spot on the photoresist surface.…”