The polymer (FSI) composed of 1H,1H,2H,2H-perfluorooctyl methacrylate (FOMA), spiropyranyl methacrylate (SPMA) and isobornyl methacrylate (IBMA) shows solubility in compliance with HFE-7500, a fluorous solvent, and photo-patterning of organic semiconductors. Highly fluorinated photoresist applicable to the process. However, it was found that the lower organic thin film was damaged during the dry etching process for transferring the photoresist pattern of FSI to the lower organic thin film. This was expected to be due to the relatively low remaining thickness and etch resistance of the photoresist. Therefore, as a first attempt to solve this problem, BMOMA, which can enhance dissolution contrast, was introduced as a comonomer in FSI (FSIB). As a result, the sensitivity to 365 nm UV light was improved, but there was no significant effect on the remaining thickness improvement. As another approach, we tried to introduce silicon atoms in highly fluorinated photoresist. Silicon atoms in photoresist can improve etch resistance by forming SiO2 under O2 plasma conditions. For this approach, FSIBT copolymer was synthesized by adding TRIS comonomer containing silicon atoms into FSIB. FSIBT still maintain solubility in fluorous solvent and excellent photo-patterning properties. Evaluating etch resistance, it was greatly improved under O2 plasma conditions. Besides, FSIBT also showed effective improvement of etch resistance in O2/CF4 plasma which is another etching condition. To check the usefulness of the developed material, the photo-patterning process of OLED pixel was performed with FSIBT on the upper layer of the electron-transport layer (ETL) thin film composed of organic semiconductors. The OLED device that went through the patterning process did not show any significant damage compared to the reference device manufactured from the chemically untreated ETL, and a clear OLED emission image could be secured. Therefore, the imaging materials improved etch resistance are expected to be usefully applied to realizing micro/nano-patterning of various organic materials in the future.