Semiconductor device and a method for manufacturing the same
View Patent ↗Disclosed are embodiments relating to a semiconductor device and a method of manufacturing a semiconductor device that may prevent an increase of a dielectric effective constant of the IMD. In embodiments, a semiconductor device may include a substrate having a source/drain area, a gate electrode formed on the semiconductor substrate, a first inter-metal dielectric layer formed on the semiconductor substrate and having a first damascene pattern, a first barrier layer formed on the damascene pattern, a first metal line formed on the first barrier layer, and a first metal capping layer formed in the first damascene pattern.
1. A method comprising:
forming a first inter-metal dielectric layer above a semiconductor substrate;
forming a first damascene pattern in the first inter-metal dielectric layer;
forming a first barrier layer and a first metal layer in the first damascene pattern;
forming a first metal line in the first damascene pattern by polishing the first metal layer and the first barrier layer to expose the surface of the first inter-metal dielectric layer;
etching the first metal line such that the uppermost surface thereof is on a plane lower than a plane of the uppermost surface of the first inter-metal dielectric layer by performing a wet etching process on the first metal line using a mask pattern after forming the first metal line;
forming a first metal capping layer above the first metal line; and
forming a second inter-metal dielectric layer above the first metal capping layer.
2. The method of claim 1 , wherein slurry used for the polishing process comprises a material having a higher etching selectivity to the first metal layer than to the first barrier layer.
3. The method of claim 1 , wherein the first damascene pattern comprises a first via hole and a first trench, and the first metal capping layer is formed in the first trench.
4. The method of claim 1 , wherein the first metal capping layer is formed by depositing at least one of Ti, SiN, SiCN, TiN, and Ru in the first damascene pattern.
5. The method of claim 1 , wherein, in forming the first metal capping layer, a prescribed dielectric material is deposited on the first metal line.
6. The method of claim 1 , wherein forming the second inter-metal dielectric layer comprises:
forming a second damascene pattern including a second via hole and a second trench in the second inter-metal dielectric layer; and
forming a second barrier layer, a second metal line, and a second metal capping layer in the second damascene pattern after forming the second damascene pattern.
7. The method of claim 6 , wherein the second metal capping layer is formed above the second metal line in the second damascene pattern.