Isolation trench fill process

Abstract

A method for filling an isolation trench structure during a semiconductor fabrication process is disclosed. The method includes a two-step deposition process that includes depositing a silicon-rich liner on the trench surface, and thereafter, filling the isolation trenches with an oxide utilizing a biased high density plasma deposition process. In a preferred embodiment, the silicon-rich liner is an in-situ HDP liner having a thickness of between 100 and 400 Angstroms, and preferably 200 Angstroms. Depositing a silicon-rich liner on the trench surface prior to depositing the high density plasma oxide eliminates the formation of defects at the surface of the isolation trench structure. Thus, the quality of the oxide fill is improved, as is yield and device performance.

Dependencies are inferred from the claim text.