Method of reducing spiral defects by adding an isopropyl alcohol rinse step before depositing sog

摘要

A method of forming an interlevel dielectric slayer of spin-on-glass is described which avoids spiral defects from occurring in the layer of spin-on-glass. Before the spin-on-glass is deposited and with the wafer spinning at a low angular velocity a first volume of isopropyl alcohol is deposited on the wafer. The wafer continues to spin at the low angular velocity for a short time. With the wafer continuing to spin at the low angular velocity a second volume, less than the first volume, of spin-on-glass is deposited on the wafer. The wafer continues to spin at the low angular velocity for a short time and then is spun at a high angular velocity for a longer time. The wafer is then removed from the apparatus used to deposit the spin-on-glass and processing of the wafer continues. Spiral defects in the layer of spin-on-glass are avoided.