Method of manufacturing a semiconductor device to prevent occurrence of short-channel characteristics and parasitic capacitance
Occurrence of short-channel characteristics and parasitic capacitance of a MOSFET on a SOI substrate is prevented. A sidewall having a stacked structure obtained by sequentially stacking a silicon oxide film and a nitride film is formed on a side wall of a gate electrode on the SOI substrate. Subsequently, after an epitaxial layer is formed beside the gate electrode, and then, the nitride film is removed. Then, an impurity is implanted into an upper surface of the semiconductor substrate with using the gate electrode and the epitaxial layer as a mask, so that a halo region is formed in only a region of the upper surface of the semiconductor substrate which is right below a vicinity of both ends of the gate electrode.
1. A method of manufacturing a semiconductor device including a semiconductor substrate, a first insulating film formed over the semiconductor substrate and a first semiconductor layer formed over the first insulating film, comprising steps:
(a) forming a gate insulating film of an n-type MISFET over the first semiconductor layer;
(b) forming a gate electrode of the n-type MISFET over the gate insulating film;
(c) forming a first side wall over the first semiconductor layer and a side surface of the gate electrode;
(d) after the step (c), forming an epitaxial layer over the first semiconductor layer which is exposed from the first side wall;
(e) after the step (d), removing the first side wall;
(f) after the step (e), forming a first impurity region of the n-type in the first semiconductor layer by an ion implantation method;
(g) after the step (f), forming a second side wall over the first impurity region and the side surface of the gate electrode;
(h) after the step (g), forming a second impurity region of the n-type in the epitaxial layer and the first semiconductor layer by an ion implantation method, the second impurity region having larger impurity concentration than the first impurity region; and
(i) after the step (h), forming silicide layers over the gate electrode and the epitaxial layer.
2. A method of manufacturing a semiconductor device according to claim 1 , further comprising a step of:
(j) between the steps (e) and (g), forming a third impurity region of a p-type in the semiconductor substrate by an ion implantation method.
3. A method of manufacturing a semiconductor device according to claim 1 ,
wherein the first side wall is formed of a silicon nitride film.
4. A method of manufacturing a semiconductor device according to claim 1 ,
wherein the second side wall is formed of a silicon nitride film.