A semiconductor device may include a source layer, a stack structure, a channel layer, a slit, and a source pick-up line. The source layer may include at least one groove in an upper surface thereof. The stack structure may be formed over the source layer. The channel layer may pass through the stack structure. The channel layer may be in contact with the source layer. The slit may pass through the stack structure. The slit may expose the groove of the source layer therethrough. The source pick-up line may be formed in the slit and the groove. The source pick-up line may be contacted with the source layer.