Method of manufacturing a double-source semiconductor device

1. A method of manufacturing a semiconductor device, the method comprising:

forming a first sacrificial layer over a first source layer;

forming a first stacked structure over the first sacrificial layer;

forming first holes passing through the first stacked structure and the first sacrificial layer;

forming a first channel layer in each of the first holes and a first memory layer surrounding the first channel layer;

forming a first slit passing through the first stacked structure and the first sacrificial layer;

forming a first opening by removing the first sacrificial layer through the first slit;

partially removing the first memory layer exposed through the first opening to expose the first channel layer; and

forming a second source layer on the first channel layer exposed through the first opening.

2. The method of claim 1 , further comprising forming an isolation insulating layer passing through at least the first sacrificial layer and located at a boundary between a cell region and a contact region and at a boundary between neighboring memory blocks.

3. The method of claim 1 , further comprising forming a second sacrificial layer over the first source layer before the forming of the first sacrificial layer, wherein the second sacrificial layer is removed during the partially removing of the first memory layer.

4. The method of claim 1 , further comprising forming an insulating layer in the first slit and the first opening after the second source layer is formed.

5. The method of claim 1 , wherein the forming of the first stacked structure comprises:

forming a lower portion of the first stacked structure over the first sacrificial layer;

forming a first slit insulating layer passing through the lower portion of the first stacked structure and extending in substantially one direction; and

forming an upper portion of the first stacked structure over the lower portion of the first stacked structure.

6. The method of claim 5 , further comprising forming a second slit insulating layer in the first slit, passing through the first stacked structure, and coupled to the first slit insulating layer to extend in substantially the one direction.

7. The method of claim 1 , wherein the forming of the second source layer comprises growing the second source layer by using the first channel layer, exposed through the first opening, as a seed.

8. The method of claim 1 , wherein the forming of the second source layer comprises:

doping the first channel layer and the first source layer exposed through the first opening with impurities; and

forming the second source layer by siliciding the first channel layer and the first source layer doped with the impurities.

9. The method of claim 1 , further comprising:

forming a third sacrificial layer on the first stacked structure, after forming the first memory layer;

forming a second stacked structure over the third sacrificial layer;

forming second holes passing through the second stacked structure and the third sacrificial layer and exposing the first channel layers; and

forming second channel layers in the second holes and second memory layers surrounding the second channel layers.

10. The method of claim 9 , further comprising:

forming a second slit through the second stacked structure and the third sacrificial layer;

forming a second opening by removing the third sacrificial layer through the second slit;

partially removing the second memory layer exposed through the second opening to expose the second channel layer; and

forming a coupling pattern over the second channel layer exposed through the second opening.

11. The method of claim 10 , wherein the forming of the coupling pattern comprises growing the coupling pattern by using the second channel layer, exposed through the second opening, as a seed.

12. The method of claim 10 , wherein the coupling pattern is formed including selective growth to reduce the contact resistance between the second channel layer and the first channel layer.

13. The method of claim 10 , wherein the coupling pattern formed over the second channel layer, exposed through the second opening, is formed at substantially the same time as the formation of the second source layer on the first channel layer exposed through the first opening.