Data storage devices and methods for manufacturing the same

A method for manufacturing a data storage device, the method comprising:

• providing a substrate including a cell region and a peripheral circuit region;
• forming a plurality of data storage structures on the cell region of the substrate;
• forming a mold layer that covers the data storage structures and extends onto the peripheral circuit region on the substrate;
• forming a mask layer that covers the cell region and the peripheral circuit region on the mold layer;
• forming a first opening in the mask layer, the first opening exposing the mold layer formed on the peripheral circuit region;
• etching the mold layer using the mask layer having the first opening as an etch mask to form a preliminary trench in the mold layer formed on the peripheral circuit region;
• forming a second opening in the mask layer, the second opening exposing the mold layer formed on the cell region;
• and
• etching the mold layer using the mask layer having the first and second openings as an etch mask to form a first trench extending from the preliminary trench toward the substrate and a second trench exposing the data storage structures.

A data storage device, comprising:

• a substrate comprising a cell region and a peripheral circuit region;
• a mold layer on the cell region and the peripheral circuit region;
• a first conductive line on the mold layer in the cell region, a bottom surface of the first conductive line being at a first height above the substrate;
• a plurality of data storage structures in contact with the first conductive line, the plurality of data storage structures being disposed between the substrate and the first conductive line;
• a second conductive line on the mold layer in the peripheral circuit region, a bottom surface of the second conductive line being at a second height above the substrate, the second height being less that the first height;
• and
• a peripheral contact plug in contact with the second conductive line and being disposed between the substrate and the second conductive line.