Electronic device and method for manufacturing the same

1. A method of manufacturing an electronic device, the method comprising:

forming a first source layer including a trench;

forming a first sacrificial layer in the trench;

forming a first structure over the first source layer, wherein the first structure includes first material layers and second material layers which are alternately stacked over each other;

forming first openings passing through the first structure and extending to the first sacrificial layer;

forming first channel layers in the first openings;

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

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

forming a second source layer in the second opening,

wherein the second source layer is coupled to the first channel layers.

2. The method of claim 1 , further comprising:

forming a second sacrificial layer over an inner surface of the trench before the forming of the first sacrificial layer; and

forming first memory layers over surfaces of the first openings, respectively, before the forming of the first channel layers.

3. The method of claim 2 , further comprising:

removing the first memory layers and the second sacrificial layer exposed through the second opening before the forming of the second source layer.

4. The method of claim 2 , wherein the second sacrificial layer includes oxide, nitride, titanium, titanium nitride, metal, or a combination thereof.

5. The method of claim 2 , wherein each of the first openings passes through the first structure and the first sacrificial layer and extends to the second sacrificial layer.

6. The method of claim 2 , wherein each of the first memory layers comprises:

a first dielectric layer formed between the sidewall of the first structure and each of the first channel layers;

a second dielectric layer formed between the first dielectric layer and each of the first channel layers, wherein the second dielectric layer has an etch selectivity with respect to the first dielectric layer; and

a third dielectric layer formed between the second dielectric layer and each of the first channel layers, wherein the third dielectric layer has an etch selectivity with respect to the second dielectric layer.

7. The method of claim 6 , further comprising:

removing the first dielectric layer exposed through the second opening to expose the second dielectric layer;

removing the second dielectric layer to expose the third dielectric layer, wherein a lower portion of the second dielectric layer has a level higher than a lower portion of the first dielectric layer; and

removing the first and third dielectric layers exposed by removing the second dielectric layer.

8. The method of claim 7 ,

wherein a portion of the second sacrificial layer is removed during the removing of the first dielectric layer, and

wherein the remaining portion of the second sacrificial layer is removed during the removing of the first and third dielectric layers.

9. The method of claim 7 , wherein, upon completion of the removing of the first and third dielectric layers, the lower portion of the first dielectric and a lower portion of the third dielectric layer have substantially the same level as the lower portion of the second dielectric layer.

10. The method of claim 7 , further comprising:

removing the first material layers through the slit to form third openings during the removing of the second dielectric layer, and

forming conductive layers in the third openings.

11. The method of claim 1 , wherein the forming of the second source layer includes selectively growing a doped polysilicon layer from each of the first channel layers.

12. The method of claim 1 , wherein the forming of the second source layer includes depositing doped polysilicon contacting each of the first channel layers.

13. The method of claim 1 , wherein the forming of the second source layer comprises forming a silicide layer on each of the first channel layers exposed by the second opening.

14. The method of claim 1 , further comprising:

forming a third sacrificial layer over the first structure after the forming of the first channel layers;

forming a fourth sacrificial layer over the third sacrificial layer, wherein the fourth sacrificial layer overlaps at least one of the first channel layers;

forming a second structure over the third and fourth sacrificial layers; and

second channel layers passing through the second structure.

15. The method of claim 14 , wherein the slit passes through the first and second structures, and

wherein the method further comprising:

removing the first, the third, and the fourth sacrificial layers through the slit to form fourth openings exposing the second channel layers, respectively, and

forming coupling patterns in the fourth openings, respectively,

wherein the coupling patterns are in contact with the first channel layers and the second channel layers, respectively.