Study of the synthesis and characterization of methacrylate photoresists

Abstract

Polymethacrylate copolymers used as single-layer resists (SLR) were investigated in this study. A photoacid generator (PAG) in the chemically amplified resist (CAR) can generate a Brönsted proton after light stimulation, which can catalyze the deprotection reaction of t-butyl methacrylate during the postexposure baking (PEB) process. Excimer lasers (KrF and ArF) were used as light source to evaluate the lithographic performance of resists. The hydrophobic property of the resist changed to hydrophilic property after the deprotection reaction by light exposure, which made the exposed resist soluble in the base developer. The deprotection reaction was analyzed by using FTIR and the reaction kinetics of the resist is discussed. The effects of the t-butyl methacrylate and the isobornyl methacrylate in the resists on the light sensitivity, contrast, reactive ion etching (RIE) resistance, and lithographic performance were systematically investigated.

Atom Transfer Radical Polymerization of 1-Ethoxyethyl (Meth)acrylate: Facile Route toward Near-Monodisperse Poly((meth)acrylic acid)

“…Note that the deprotection step can alternatively be carried out at lower temperatures under acid-catalyzed conditions, e.g., using a photo acid generator . This simple deprotection step without the need for further purification adds new prospects for the use of these polymers in thermoresponsive systems and in applications where a change from hydrophobic to hydrophilic properties is needed, for instance in photoresist technology . Even reversible systems are possible …”

Preparation and characterization of molecular photoresists: Crosslinkable positive and water developable negative tones

“…For these technologies, new photolithography resist materials are required to have high transparency at the exposure wavelength and high stability under dry etching conditions. The chemical amplification resist system is a potential future photolithographic technology using a new irradiation method 9–12. In this system, a generating acid is produced in a photo‐acid generator when light is present, which promotes deprotection of the protecting groups, such as t ‐butyl ester, acetal, trimethylsilyl, and tetrahydropyranyl groups to achieve higher resolution resist materials 13–16.…”