Microstructure and resolution of etched patterns of Photoresist (AZP4620) layers spin-coated under artificially elevated gravity accelerations by two-axis spin coating technology

The resolution of miniaturized photoresist patterns plays a vital role in the microelectronic industries. This study investigates the quality of photoresist (AZP4620) etched patterns spin-coated under gravity conditions. The elevation of gravity acceleration is artificially exerted within a two-axis spin coater. The evaporation rate of photoresist solvents under natural and elevated gravity accelerations is measured and discussed. An FTIR characterizes the microstructure of films synthesized under various gravity conditions (1, 100, 200, and 300 g). A designed mask’s patterns are directly exposed to the fabricated films by UV light within a photolithography method. The exposed patterns are finally etched in a developer. The surface and cross-section of miniaturized etched patterns are imaged by an SEM, which shows enhancements in the resolution of the etched patterns spin-coated under a higher gravity field. The evaporation rate of the photoresist increased while elevating the gravity acceleration. The elevation of gravity can be a dominant force in changing the crystalline structure of photoresists. FTIR shows a decrease in the lighter chemical bonds, such as gases, where the coated films synthesize under higher gravity acceleration.