Method of manufacturing semiconductor device
View Patent ↗A method of manufacturing a semiconductor device includes forming a trench in an interlayer dielectric film on the semiconductor substrate, the trench reaching a semiconductor substrate and having a sidewall made of silicon nitride film; depositing a gate insulation film made of a HfSiO film at a temperature within a range of 200 degrees centigrade to 260 degrees centigrade, so that the HfSiO film is deposited on the semiconductor substrate which is exposed at a bottom surface of the trench without depositing the HfSiO film on the silicon nitride film; and filling the trench with a gate electrode made of metal.
1. A method of manufacturing a semiconductor device comprising:
forming a trench in an interlayer dielectric film on a semiconductor substrate, and forming a silicon dioxide film as a part of a gate dielectric film on the semiconductor substrate, the trench reaching the semiconductor substrate and having a sidewall made of silicon nitride film;
depositing a gate dielectric film made of a HfSiO film as another part of the gate dielectric film, so that the HfSiO film is selectively deposited on the silicon dioxide film which is exposed at a bottom surface of the trench rather than on the silicon nitride film; and
filling the trench with a gate electrode made of metal.
2. The method of manufacturing a semiconductor device according to claim 1 , wherein:
after depositing the silicon dioxide film as a part of the gate dielectric film, either one of or both nitriding and heat treating are performed to the HfSiO film.
3. The method of manufacturing a semiconductor device according to claim 1 , further including:
setting a temperature condition of depositing the HfSiO film so that a deposition delay time attributable to a material of the silicon nitride film and a deposition delay time attributable to a material of the silicon dioxide film are mutually different.
4. The method of manufacturing a semiconductor device according to claim 1 , wherein:
the HfSiO film is deposited on the silicon dioxide film according to a MOCVD method.
5. The method of manufacturing a semiconductor device according to claim 1 , wherein:
the silicon dioxide film as a part of the gate dielectric film is formed by oxidizing the semiconductor substrate using thermal oxidation, radical oxidation, plasma oxidation, or chemical oxidation.
6. The method of manufacturing a semiconductor device according to claim 1 , wherein:
the HfSiO film is formed according to a chemical vapor deposition which uses at least tetrakis-dimethyl-amino-silicon and tetrakis-diethyl-amino-hafnium.
7. The method of manufacturing a semiconductor device according to claim 1 , the method further comprising:
before forming the trench,
forming a dummy gate in a region of the semiconductor substrate in which the gate electrode is formed;
introducing impurity into the semiconductor substrate by using the dummy gate as a mask to form an extension layer;
depositing a material of a sidewall protection film made of the silicon nitride film on the semiconductor substrate so as to cover the dummy gate;
anisotropically etching the material of the sidewall protection film to form the sidewall protection film on the side surface of the dummy gate;
depositing the material of the interlayer dielectric film on the semiconductor substrate so as to cover the dummy gate and the sidewall protection film; and
flattening the interlayer dielectric film to expose the upper surface of the dummy gate, wherein:
the trench is formed by removing the dummy gate.
8. The method of manufacturing a semiconductor device according to claim 1 , wherein:
a temperature of the depositing process of the gate dielectric film is within a range of 200 degrees centigrade to 260 degrees centigrade.