Planar selective field oxide isolation process using SEG/ELO

摘要

An isolation method for separating active regions on a semiconductor substrate is disclosed. Portions of the substrate not corresponding to the active regions are etched to a predetermined depth. After some oxide, nitride and dielectric deposition steps, a photoresist is patterned on the dielectric material such that the photoresist completely covers the active regions of the substrate and overlaps into the portions of the substrate that are eventually to represent field oxide regions. Any portion of the dielectric, nitride oxide layers that are not covered by the photoresist are removed and a combined step of selective epitaxial growth (SEG) and epitaxial lateral overgrowth (ELO) is performed. The exposed silicon is then oxidizing and the dielectric, nitride and oxide layers are removed from the active regions of the substrate. The semiconductor device is then ready for subsequent processing.