Bit line landing pad and borderless contact on bit line stud with etch stop layer and manufacturing method thereof

摘要

An etch-stop layer is selectively provided between layers of a multiple-layered circuit so as to allow for outgassing of impurities during subsequent fabrication processes. The etch-stop layer is formed over an underlying stud so as to serve as an alignment target during formation of an overlying stud formed in an upper layer to be coupled to the underlying stud. In this manner multiple-layered circuits, for example memory devices, can be fabricated in relatively dense configurations.