Method of solving contact oblique problems of an ILD layer using a rapid thermal anneal

摘要

A method of annealing an interlevel dielectric (IDL) layer 24 composed of PE-TEOS oxide before contact openings are formed in the ILD layer. The anneal prevents the contact openings 30 in IDL layer 24 from shifting and causing contact problems (contact oblique 33). The method begins by forming a first insulating layer 16 20 over a semiconductor structure 12. An ILD layer 24 composed of silicon oxide formed by a PECVD process using TEOS overlying the structure 12. In a key step, first rapid thermal anneal (RTA) is performed on the interlevel dielectric layer 24. The first RTA is preferably performed at a temperature in a range of between about 940 and 1100 DEG C. for a time in a range of between about 10 and 120 seconds. A contact hole 30 is then formed through the first insulating layer and the interlevel dielectric layer 24. The invention's first rapid thermal anneal prevents the ILD layer 24 from shrinking and shifting that distorts the contact hole 30.