Sub-atmospheric pressure thermal chemical vapor deposition (SACVD) trench isolation method with attenuated surface sensitivity

摘要

A method for filling a trench within a silicon substrate. There is first provided a silicon substrate having a trench formed therein. There is then formed upon the substrate and within the trench a gap filling silicon oxide trench fill layer employing an ozone assisted thermal chemical vapor deposition (SACVD) method. There is then carried out a densification of the gap filling silicon oxide trench fill layer by annealing in an oxidizing atmosphere at an elevated temperature. Finally, the gap filling silicon oxide trench fill layer is planarized by chemical mechanical polish (CMP) planarization to form the silicon oxide trench filling layer with attenuated surface sensitivity and with an enhanced bulk quality and reduced trench recess at corners.