3D non-volatile semiconductor device and manufacturing method of the device

A semiconductor device, comprising:

• a source structure formed over a base;
• an etch prevention layer formed over the source structure;
• bit lines;
• a stack structure located between the etch prevention layer and the bit lines and including conductive layers and insulating layers that are alternately stacked on each other;
• a channel structure extending in a vertical direction in the stack structure and the etch prevention layer;
• a slit extending in the vertical direction in the stack structure and the etch prevention layer;
• a spacer formed along an inner wall of the slit;
• and
• a source contact structure formed along an inner wall of the spacer,
• wherein a lower portion of the channel structure is located in the source structure and a sidewall of the lower portion of the channel structure is in direct contact with the source structure,
• the source contact structure and the etch prevention layer are physically separated from each other by the spacer, and
• the conductive layers correspond to at least one source select line and a plurality of word lines.