Protective liner layers in 3d memory structure

A memory device comprising:

• a stack of gate electrode layers alternating with interconnect dielectric layers that are arranged over a substrate;
• a first source/drain conductive line and a second source/drain conductive line extending vertically through the stack of gate electrode layers;
• a channel layer and a memory layer extending between the first and second source/drain conductive lines;
• a first barrier structure extending vertically through the stack of gate electrode layers and arranged directly between the first and second source/drain conductive lines;
• a first protective liner layer arranged between the first barrier structure and the first source/drain conductive line, wherein the first protective liner layer is arranged on outer sidewalls and a lower surface of the first source/drain conductive line;
• and
• a second protective liner layer arranged on an upper surface of the first source/drain conductive line.

A method comprising:

• forming a stack of dummy gate electrode layers arranged between interconnect dielectric layers over a substrate;
• forming a first trench within the stack of dummy gate electrode layers;
• replacing the dummy gate electrode layer with gate electrode layers;
• forming a memory layer, a channel layer, and a first dielectric layer within the first trench;
• filling remaining portions of the first trench with a dielectric material;
• forming first openings within the dielectric material to form first barrier structures within the first trench;
• forming a first protective liner material within the first openings;
• forming sacrificial structures within the first openings;
• removing portions of the first protective liner material and portions of the sacrificial structures to respectively form a first protective liner layer and second openings within the sacrificial structures;
• forming a second protective liner layer within the second openings of the sacrificial structures;
• forming second barrier structures within remaining portions of the second openings;
• and
• removing the sacrificial structures and replacing the sacrificial structures with a conductive material to form source/drain conductive lines surrounded by the first and second protective liner layers.