| 摘要 |
PURPOSE:To flatten the surface of filled contact hole by performing a CVD (chemica vapor deposition) method, to eliminate the generation of cavities and to enable to accomplish the three dimenshional constitution of an LSI (large scale integrated circuit) by a methold wherein a contact hole is formed in such a manner that it has an inverted taper-shaped cross section, and an epitaxial growing method is performed. CONSTITUTION:A PSG insulating layer is formed by introducing mixed gas consisting of silane, phosphine and oxygen, by heating up an Si substrate to approximately 500 deg.C and by performing a CVD method. At this time, the corrosion-resisting property can be increased as going to the upper part of the PSG insulating film from the lower part by gradually reducing the content of P from 15% to 5%. Then, a resist is coated on the PSG film 13, and an inverted taper-shaped contact hole 14 can be formed by performing a selective etching on the contact hole formed position using the hydrofluoric acid of approximately 5%. Subsequently, when an epitaxial growing method is perfomed on the contact hole 14, the generation of cavities can be prevented, and a relatively flat surface condition can also be obtained. |
