Elucidating the patterning mechanism of zirconium-based hybrid photoresists

We report a series of studies aimed at shedding more light on the development mechanism of zirconium (Zr)-based extreme-UV hybrid photoresists. In earlier works, our group demonstrated that Zr-based hybrid resists are capable of resolving 30-nm half-pitch features with a very high sensitivity in the range of 1 to 20 mJ/cm2, which renders these materials potential candidates in the area of nonchemically amplified inorganic resists. While attractive because of its high sensitivity, Zr-methacrylic acid suffers from scumming problems. In an effort to better understand what controls sensitivity and scumming phenomena, we employed a combination of analytical techniques (electrospray ionization mass spectrometry, x-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy) to study the patterning mechanism in detail, to be able to optimize the development process and develop systems with optimal features.