Method for manufacturing a capacitor of a semiconductor device
A method for manufacturing a semiconductor device is disclosed. A method for manufacturing a semiconductor device includes forming a device isolation structure for defining an active region, forming a buried word line traversing the active region, forming one or more insulation film patterns over the buried word line, forming a line pattern including a first conductive material at a position between the insulation film patterns, and forming a plurality of storage node contacts (SNCs) by isolating the line pattern. As a result, when forming a bit line contact and a storage node contact, a fabrication margin is increased.
1. A method for manufacturing a semiconductor device, the method comprising:
forming a device isolation structure defining an active region;
forming first and second buried word lines crossing the active region;
forming first and second insulation film patterns over the first and the second buried word lines;
forming a line pattern including a first conductive material between the first and second insulation film patterns;
depositing a hard mask film over the line pattern;
patterning the hard mask film in a direction orthogonal to the first and the second buried word lines;
forming a trench by patterning the line pattern using the patterned hard mask film as an etch mask, thus forming a plurality of storage node contacts;
forming a third insulation film over an inner sidewall of the trench; and
filling the trench with a fourth insulating film over the third insulation film.
2. The method according to claim 1 , wherein the active region has a size and a shape corresponding to those of a 6F2-sized unit cell.
3. The method according to claim 1 , wherein the word line is formed orthogonal to a major-axis direction of the active region.
4. The method according to claim 1 , wherein the forming of the first and second insulation film patterns includes:
forming first and second insulation films over the active region and the first and the second buried word lines; and
removing a portion of the first and the second insulation films provided in regions where the line pattern is to be formed.
5. The method according to claim 1 , wherein the first and second insulation film patterns include a plurality of insulation layers, and the plurality of insulation layers includes two oxide films and a nitride film located between the two oxide films.
6. The method according to claim 1 , wherein the hard mask film is patterned in a direction orthogonal to the buried first and second word lines to isolate the line pattern and to form storage node contacts in an island pattern.
7. The method according to claim 1 , the method further comprising:
forming a bit line contact hole over the active region;
forming spacers at sidewalls of the bit line contact hole;
forming a bit line contact by burying a second conductive material between the spacers; and
forming a bit line over the bit line contact.
8. The method according to claim 7 , wherein the storage node contacts are partially etched and exposed when the bit line contact is formed.
9. The method according to claim 8 , wherein the storage node contact is disposed in a cell region and has substantially the same height as that of a gate pattern disposed in a peripheral region.
10. The method according to claim 8 , wherein the bit line contact is disposed in a cell region, and the top of the bit line contact is formed to be higher than the storage node contact in the cell region.
11. The method according to claim 7 , wherein the spacers each include a nitride film.
12. The method according to claim 7 , wherein each of the first and second conductive materials include polysilicon.
13. The method of claim 1 , wherein the step of forming the trench includes:
patterning the line pattern to form a plurality of island patterns isolated from each other by the trench,
wherein the plurality of island patterns are configured to serve as the storage node contacts.