A novel acrylic prepolymer/methacrylate modified nano-SiO2 composite used for negative photoresist

• We synthesized a new type of nano-SiO2 modified with methacrylate.
• A series of organic–inorganic photoresists were prepared with the nano-SiO2.
• The photosensitivity was greatly enhanced with the addition of nano-SiO2.
• The nanocomposites photoresists had good dimensional stability.

A novel nanocomposite consisting of methacrylate modified nano-SiO2 (SiO2MA) and acrylic prepolymer (G-ACP) was found a potential candidate as a negative photoresist. The SiO2MA was synthesized from glycidyl methacrylate (GMA), 3-aminpropyltriethoxysilane (KH550) and a pre-synthesized nano-SiO2 through the sol–gel process. G-ACP was synthesized through radical polymerization of five monomers, followed by grafting with carboxyl and methacrylate group. The molecular structures of monomers and polymers were characterized by FT-IR and 1H NMR spectroscopy. Finally, SiO2MA was added into G-ACP in different contents and treated with a standard thermal and UV-exposure process to obtain a series of cured organic–inorganic nanocomposite photoresists. The formed nanocomposite photoresists exhibited improved photosensitivity and had a low Dn0.5 of 26.8 mJ cm−2 with 13.7 wt% SiO2MA. Moreover, the thermal and mechanical properties also showed great enhancement while all of the photoresists had a nice line pattern of less than 25 μm.

Figure optionsDownload as PowerPoint slide