Gap fill integration

摘要

Novel gap fill schemes involving depositing both flowable oxide films and high density plasma chemical vapor deposition oxide (HDP oxide) films are provided. According to various embodiments, the flowable oxide films may be used as a sacrificial layer and/or as a material for bottom up gap fill. In certain embodiments, the top surface of the filled gap is an HDP oxide film. The resulting filled gap may be filled only with HDP oxide film or a combination of HDP oxide and flowable oxide films. The methods provide improved top hat reduction and avoid clipping of the structures defining the gaps.