Patent ID: 7727906

Claim:
A method for filling gaps in a semiconductor substrate comprising: providing a high density plasma chemical vapor deposition reaction chamber; introducing one or more of a reducing gas and one or more of an oxidizing gas into the reaction chamber; forming a first plasma and maintaining the first plasma for a sufficient time to treat the chamber; heating the treated chamber for a sufficient time to pre-heat the treated chamber; introducing a dielectric process gas into the treated and heated chamber; depositing a dielectric precoat in the treated and heated chamber using a HDP CVD process; introducing additional of the one or more reducing gas and the one or more oxidizing gas into the reaction chamber prior to processing a substrate in the chamber; forming a second plasma and maintaining the second plasma for a sufficient time to treat the chamber having the dielectric precoat; providing a semiconductor substrate having a gap to be filled in the treated and precoated high density plasma chemical vapor deposition (HDP CVD) reaction chamber; heating the substrate; introducing a dielectric process gas into the chamber; depositing a dielectric in the gap using a HDP CVD process; introducing an etchant into the reaction chamber if an etch is required and forming an etchant plasma to etch the gap; repeating the above deposition and etch steps until the gap is filled; determining completion of the deposition and etch steps of the semiconductor substrate; once the deposition and etch steps are complete, introducing one or more of a reducing gas and one or more of an oxidizing gas into the reaction chamber; forming a plasma and maintaining the plasma for a sufficient time to treat the chamber; removing the gap filled semiconductor substrate from the reaction chamber; and repeating the above steps except for the dielectric precoat deposition step until all the substrates for a predetermined number of substrates (batch) have been processed whereby fluorine loading effects in the chamber on the dielectric deposition uniformity is reduced and the substrates have decreased deposition thickness variations.