Advanced CMOS isolation utilizing enhanced oxidation by light ion implantation

摘要

A method for forming field isolation regions in multilayer semiconductor devices comprises the steps of masking active regions of the substrate, forming porous silicon in the exposed field isolation regions, removing the mask and oxidizing the substrate. A light ion impurity implant is used to create pores in the substrate. Substrate oxidation proceeds by rapid thermal annealing because the increased surface area of the pores and the high reactivity of unsaturated bonds on these surfaces provides for enhanced oxidation.