US Patent 9716099 Semiconductor device and manufacturing method thereof

A semiconductor device includes a first source seed layer, a second source seed layer disposed over the first source seed layer while being spaced apart from the first source seed layer, a stacked structure formed on the second source seed layer, channel layers extending inside the first source seed layer by penetrating the stacked structure, and an interlayer source layer extending into a space between the first source seed layer and the second source seed layer while contacting each of the channel layers, the first source seed layer, and the second source seed layer.