Capacitor in semiconductor device and manufacturing method
View Patent ↗The capacitor in a semiconductor device includes a substrate, a lower electrode formed over the substrate, a diffusion barrier formed over the lower electrode, a plurality of agglomerates formed over the diffusion barrier, a dielectric layer formed over the surface of the agglomerates to form an uneven surface, and an upper electrode formed over the dielectric layer.
1. A method of manufacturing a capacitor in a semiconductor device, comprising:
forming a first metal film over a substrate;
forming a second metal film over the first metal film;
forming a low-melting-point metal film over the second metal film;
thermally treating the low-melting-point metal film to form spherical agglomerates;
forming a dielectric film over the agglomerates;
forming a third metal film over the dielectric film; and
etching the third metal film, the dielectric film, the agglomerates, the second metal film and the first metal film.
2. The method of claim 1 , wherein the second metal layer is in an oxidized state, and wherein said etching said second metal layer comprises etching an oxidized metal layer.
3. The method of claim 1 , wherein the second metal film is formed of Ru.
4. The method of claim 3 , further comprising oxidizing the second metal film, after forming the second metal film, in which the oxidizing is performed by thermally treating the second metal film at 300˜400° C. in an atmosphere of N 2 O or O 2 gas.
5. The method of claim 1 , wherein the low-melting-point metal film is formed of Zn or Sn.
6. The method of claim 1 , wherein the low-melting-point metal film is formed through atomic layer deposition.
7. The method of claim 1 , wherein said thermally treating is performed at a temperature equal to or less than 200° C. in an inert gas atmosphere.
8. The method of claim 7 , wherein the inert gas comprises at least one of Ar, He, Ne, Kr, Xe, and Rn.
9. The method of claim 1 , wherein the dielectric film is formed with a thickness of about 100 Å.