Organic dry development rinse (O-DDR) process for spin-on MOR to prevent pattern collapse

Pattern collapse emerges as a key factor leading to the failure of photoresist patterns in high-resolution EUV lithography. Its significance escalates as feature sizes decrease and pitches become smaller transitioning to high-NA EUV, potentially leading to challenges with regards to resolution. Collapse arises from capillary forces acting on the resist surface during wafer drying. Consequently, the optimal strategy to mitigate pattern collapse involves eliminating any drying steps post-lithography processing. In this study, we introduce the O-DDR process for spin-on MOR, effectively eliminating capillarity and eradicating the pattern collapse issue without tone inversion. Figure 1 illustrates the O-DDR process, which involves dispensing O-DDR material instead of employing a spin-drying developer, without introducing any extra processing steps. After the dry etching process, we observe that the resist pattern remains intact without any collapse. Furthermore, we conduct an analysis of the O-DDR process, with the goal of expanding the window for a failure-free process with pitch 32nm pillars and pitch 28nm line and space in EUV lithography.