Method for reducing precipitate defects using a plasma treatment post BPSG etchback

摘要

The present invention provides a method of manufacturing an interlevel dielectric layer (ILD) which has reduced precipitates after an etch back of the borophosphosilicate glass (BPSG) ILD layer. A dielectric layer containing boron and phosphorous is deposited on the substrate. A reflow process is performed on the dielectric layer at a temperature in a range of between about 800 DEG and 950 DEG C. The dielectric layer is etched back using a reactive ion etch. In an important step, a surface treatment is performed on the dielectric layer thorough a plasma treatment. A plasma source gas for the surface treatment is of a gas selected from the group consisting of Ar, NO2, N2, and O2, at a temperature in a range of between about 250 DEG and 400 DEG C. at a pressure in a range of between about 1 mtorr and 5 torr, at a RF power in a range of between about 300 and 400 watts, and for a time in a range of between about 15 and 80 seconds.