Buried contact structure in semiconductor device and method of making the same

摘要

A first interlayer insulating layer is formed over a semiconductor substrate having a semiconductor element. A first line is formed on the first interlayer insulating layer and is connected to the semiconductor element via a contact hole. A second interlayer insulating layer is formed over the first line and the first interlayer insulating layer. An etch barrier layer is formed on the second interlayer insulating layer. A buried contract hole extends through the etch barrier layer and the first and second interlayer insulating layers. An insulating spacer is formed on the side walls of the buried contact hole. A second line is formed on the etch barrier layer and connected to the semiconductor element via the buried contact hole. The buried contact hole has a substantially vertical profile at a top end thereof to provide a sufficient misalignment margin between the buried contact hole and the second line.