Semiconductor device and manufacturing method of the same
A semiconductor device includes a substrate including a cell region and a peripheral region, a cell stacked structure stacked on the substrate in the cell region, a channel layer in one structure penetrating the cell stacked structure, a driving transistor formed in the peripheral region, and a plug structure coupled to the driving transistor and including a stacking structure of at least two contact plugs shorter than the channel layer, wherein each of the contact plugs is arranged at a same height as a part of the cell stacked structure.
1. A method of manufacturing a semiconductor device, the method comprising:
alternately stacking first and second material layers on a substrate in which a driving transistor is arranged;
forming first and second lower buried layers penetrating the first and second material layers and spaced apart from each other, wherein the first and second lower buried layers are formed at the same time;
alternately stacking third and fourth material layers on the first and second material layers penetrated by the first and second lower buried layers;
forming a first upper through hole and a second upper through hole penetrating the third and fourth material layers and exposing the first and second lower buried layers, respectively, wherein the first and second upper through holes are formed at the same time; and
forming an upper buried layer in the first upper through hole while leaving the second lower buried layer exposed through the second upper through hole.
2. The method of claim 1 , further comprising, after the forming of the upper buried layer:
removing the second lower buried layer through the second upper through hole; and
forming a channel layer in a region from which the second lower buried layer is removed and in the second upper through hole.
3. The method of claim 2 , further comprising, after the forming of the channel layer:
forming an insulating layer on the third and fourth material layers including the channel layer and the upper buried layer;
forming first and second contact holes penetrating the insulating layer and exposing the upper buried layer and the channel layer, respectively;
removing the upper buried layer through the first contact hole to open the first upper through hole; and
forming a contact plug filling the first contact hole and the first upper through hole and a channel contact plug filling the second contact hole by filling the first contact hole, the second contact hole, and the first upper through hole with a conductive material.
4. The method of claim 3 , wherein the contact plug is coupled to the first lower buried layer.
5. The method of claim 3 , further comprising, after the forming of the contact plug and the channel contact plug:
separating the first to fourth material layers into a cell stacked structure surrounding the channel layer and a peripheral stacked structure surrounding the first lower buried layer and the contact plug.
6. The method of claim 5 , further comprising, after the separating of the cell stacked structure from the peripheral stacked structure:
replacing the second and fourth material layers of the cell stacked structure with fifth material patterns.
7. The method of claim 6 , wherein the first lower buried layer is extended to directly contact the driving transistor when the peripheral stacked structure overlaps with the driving transistor.
8. The method of claim 6 , further comprising before alternately stacking the first and second material layers:
forming a lower plug structure coupled to the driving transistor; and
forming a connection wire coupled to an upper surface of the lower plug structure and extended toward a bottom surface of the first lower buried layer.
9. The method of claim 2 , further comprising, after the forming of the channel layer:
forming a slit penetrating the first to fourth material layers; and
replacing the second and fourth material layers with fifth material patterns through the slit so that the channel layer is surrounded by the fifth material patterns.
10. The method of claim 1 , wherein the first and second lower buried layers are formed of a conductive material having an etch selectivity against the first to fourth material layers.
11. The method of claim 1 , wherein the first and second lower buried layers are formed with a conductive material including at least one of Silicon Germanium (SiGe) and Carbon (C).
12. The method of claim 1 , wherein the upper buried layer is formed of a material having an etch selectivity against the first lower buried layer, the first material layer, the second material layer, the third material layer and the fourth material layer.
13. A method of manufacturing a semiconductor device, the method comprising:
alternately stacking first and second material layers on a substrate in which a driving transistor is arranged;
forming first and second lower buried layers penetrating the first and second material layers and spaced apart from each other, wherein the first lower buried layer is coupled to the driving transistor, wherein the first and second lower buried layers are formed at the same time;
alternately stacking third and fourth material layers on the first and second material layers penetrated by the first and second lower buried layers;
forming a first upper through hole and a second upper through hole penetrating the third and fourth material layers and exposing the first and second lower buried layers, respectively, wherein the first and second upper through holes are formed at the same time; and
forming an upper buried layer in the first upper through hole while leaving the second lower buried layer exposed through the second upper through hole.