Cryogenic single-component micro-nano solid nitrogen particle production using laval nozzle for physical resist removal-cleaning process

The innovative characteristics of the cryogenic single-component micro-nano solid nitrogen (SN₂) particle production using super adiabatic Laval nozzle and its application to the physical resist removal-cleaning process are investigated by a new type of integrated measurement coupled computational technique. The originality to be noted in the present study is that the continuous production of micro-nano SN₂ particle is achieved by using single component gas-liquid two-phase flow of subcooled nitrogen through a Laval nozzle (converging-diverging nozzle). As a result of present computation, it is found that high-speed ultra-fine SN₂ particle is continuously generated due to the freezing of liquid nitrogen (LN₂) droplet induced by rapid adiabatic expansion of subsonic subcooled two-phase subcooled nitrogen flow passing through the Laval nozzle. Furthermore, the effect of SN₂ particle diameter, injection velocity, and attack angle to the wafer substrate on resist removal-cleaning performance is investigated in detail by integrated measurement coupled computational technique.