ИСТИНА

Pyrolysis of microstructures made by two-photon lithography (TPP) allows to increase the printing resolution and modify their chemical composition at the same time. In this work, we compare the effect of pyrolysis on TPP-made solid objects sized by tenths of micrometers produced from three photoresists: IP-Dip, OrmoComp®, and SZ2080TM. We analyzed the structures' size reduction, modification of chemical composition, and adhesion to the silicon wafer substrate for the pyrolysis temperatures of 450°C and 690°C [1]. Fig. 1 shows SEM images of microcube structure with 34×40.2×50 μm3 dimensions made of IP-Dip before and after pyrolysis at 450◦C. As a result of pyrolysis, the microcube shrinks and deforms. However, with adjusted printing parameters and pyrolysis procedure, it is possible to achieve uniform shrinkage and apply pyrolysis as a repeatable post-processing step for TPP-made structures made of IP-Dip, OrmoComp®, and SZ2080TM. Using thermogravimetric analysis, scanning electron microscopy, and X-ray energy dispersive analysis, we have detected pyrolysis-induced changes in microstructures' size, chemical composition, survival rate, and adhesion. In conclusion, we have analyzed the effect of pyrolysis on microstructures made of three photoresists for the temperatures of 450◦C and 690◦C. All photoresists have their advantages: pyrolyzed IP-Dip structures have the highest shrinkage ratio of 2.1 at the temperature of 450◦C, OrmoComp® structures demonstrate best adhesion and survival rate after pyrolysis, while SZ2080TM structures are good at decoupling from the substrate's surface and uniform shrinking. The results of the current work can be useful for overcoming the regular TPP restrictions. This work was supported by Russian Science Foundation (20-12-00371), the Ministry of Science and Higher Education of the Russian Federation (14.W03.31.0008), and MSU Quantum Technology Center.