A SPIN-ON DIELECTRIC MATERIAL FOR HIGH ASPECT RATIO GAP FILL

摘要

This communication describes the results of a potential spin-on glass (SOG) solution for narrow and high aspect ratio trench fill in both shallow trench isolation (STI) and pre-metal dielectric (PMD) applications. We have focused our development work on a hydrogen silsesquioxane (HSQ, (HSiO_(3/2))_n) material, which offers the advantage of a carbon free gap fill solution. The main challenge for carbon-free SOG materials is to achieve material densification in the nano-scale gaps during thermal processing that of the gap filled material during the wet cleaning steps. This paper reports some approaches and findings on material densification in the nano-scale gaps and the results of subsequent wet etch tests.