Capacitor of semiconductor device and method for fabricating the same
A method for fabricating a semiconductor device includes forming an interlayer insulating film over a semiconductor substrate. The interlayer insulating film is selectively etched to form a hole defining a storage node region. A lower electrode is formed in the hole. A support layer is formed over the lower electrode. The support layer fills an upper part of the hole and exposes the interlayer insulating film. A dip-out process is performed to remove the interlayer insulating film. The supporting layer is removed to expose the lower electrode. A dielectric film is formed over the semiconductor substrate including the lower electrode. A plate electrode is formed over the semiconductor substrate to fill the dielectric film and the lower electrode.
1. A method for fabricating a semiconductor device, the method comprising:
forming an interlayer insulating film over a semiconductor substrate;
selectively etching the interlayer insulating film to form a hole defining a storage node region;
forming a lower electrode in the hole;
forming a support layer over the lower electrode, the support layer filling an upper part of the hole and exposing the interlayer insulating film, wherein the support layer comprises an amorphous carbon film;
performing a dip-out process to remove the interlayer insulating film;
removing the support layer to expose the lower electrode;
forming a dielectric film over the semiconductor substrate including the lower electrode; and
forming a plate electrode over the dielectric film.
2. The method of claim 1 , further comprising forming an etch stop layer between the interlayer insulating layer and the semiconductor substrate.
3. The method of claim 1 , wherein forming the lower electrode comprises:
forming a conductive layer over the semiconductor substrate including the hole; and
blanket-etching the conductive layer until the interlayer insulating film is exposed.
4. The method of claim 1 , wherein a thickness of the support layer is in a range of about 50 nm to 1,000 nm.
5. The method of claim 1 , wherein forming the support layer comprises:
forming a supporting layer over the semiconductor substrate including the lower electrode;
forming a photoresist film over the supporting layer;
exposing and developing the photoresist film by using an exposure mask to form a photoresist pattern defining the interlayer insulating film disposed between the lower electrodes;
etching the supporting layer by using the photoresist pattern as an etching mask to expose the interlayer insulating film; and
removing the photoresist pattern.
6. The method of claim 1 , wherein the lower electrode comprises a titanium nitride (“TiN”) film.
7. The method of claim 3 , wherein blanket-etching the conductive layer comprises performing a Chemical Mechanical polishing (“CMP”) method or an etch-back method.
8. The method of claim 5 , further comprising forming a bottom anti-reflective coating between the photoresist film and the supporting layer.
9. The method of claim 5 , wherein a thickness of the photoresist film is in a range of about 100 nm to 400 nm.
10. The method of claim 5 , wherein the exposure mask is a storage node mask or a mask exposing a portion of the interlayer insulating film between the lower electrodes.
11. The method of claim 5 , wherein a light source of the exposing process is selected from the group consisting of ArF, EUV, E-beam, x-ray, and ion-beam.
12. The method of claim 8 , wherein a thickness of the bottom anti-reflective coating is in a range of about 20 nm to 50 nm.