Gas jet reduction of iso-dense field thickness bias for gapfill process

摘要

A system and method affecting mass transport to reduce or eliminate iso-dense bias in spin-on-dielectric (SOD) or spin-on-glass (SOG) processes use a nozzle to dispense the liquid dielectric and a separate nozzle for jetting N₂ or other gas onto a semiconductor wafer. The gas is jetted onto the wafer shortly after spin-on-dielectric liquid is dispensed. The jetting of the gas in the spin-coating process increases the volumetric flow of the liquid coating material in the radial direction, which in turn reduces the field thickness above isolated or no patterned areas to that at the more densely patterned areas, thereby improving the uniformity of the spun-on dielectric thickness on the wafer.