Methods for fabricating memory devices using sacrificial layers

摘要

A protection layer is formed on a semiconductor substrate having a cell array region and an alignment key region. A plurality of data storage elements are formed on the protection layer in the cell array region. An insulating layer is formed on the data storage elements, a barrier layer is formed on the insulating layer, and a sacrificial layer is formed on the barrier layer. The sacrificial layer, the barrier layer and the insulating layer are patterned to form contact holes that expose the data storage elements, and conductive plugs are formed in the contact holes. The sacrificial layer is etched to leave portions of the conductive plugs protruding from the barrier layer. The protruding portions of the conductive plugs are removed by polishing.