Semiconductor device and method of manufacturing the same

1. A method of manufacturing a semiconductor device comprising a Fin field effect transistor, the method comprising:

(1) preparing a semiconductor substrate;

(2) forming an oxide film on a surface of the semiconductor substrate;

(3) forming an isolation region in the semiconductor substrate;

(4) forming a mask pattern on the entire semiconductor substrate expect for the isolation region;

(5) etching the oxide film away through the mask pattern as a mask to expose the semiconductor substrate;

(6) forming a sacrifice oxide film on a part of the semiconductor substrate exposed in step (5);

(7) removing the sacrifice oxide film to expose the semiconductor substrate;

(8) forming a gate insulating film on the semiconductor substrate exposed in step (7);

(9) forming a polysilicon film all over the semiconductor substrate;

(10) executing a CMP process on the polysilicon film through the mask pattern as a stopper;

(11) forming a metal film all over the polysilicon film;

(12) forming a gate electrode by allowing at least a part of the polysilicon film to react with at least a part of the metal film to silicidize the metal;

(13) forming a mask A on the gate electrode;

(14) removing the metal film through the mask A as a mask;

(15) removing the mask pattern; and

(16) implanting impurity into the semiconductor substrate through the mask A as a mask to form a source/drain region.

2. The method of manufacturing a semiconductor device according to claim 1 , wherein step (15) comprises:

forming a protect film all over the semiconductor substrate; and

performing an etch back process to remove the mask pattern and the protect film on the mask pattern so as to leave the mask A on the gate electrode.

3. The method of manufacturing a semiconductor device according to claim 1 , wherein the metal is W, and in step (12), a part of the polysilicon film and a part of the metal film are allowed to react with each other to silicidize the metal to form the gate electrode of a laminate structure with the W, WSi, and polysilicon film laminated in this order from above.

4. The method of manufacturing a semiconductor device according to claim 1 , wherein the mask pattern and the mask A comprise silicon nitride.

5. The method of manufacturing a semiconductor device compositing a plurality of the Fin field effect transistors according to claim 1 , wherein in step (12), a plurality of the gate electrodes are formed, and in step (16), a plurality of the source/drain regions are formed.

6. A method of manufacturing a semiconductor device comprising a Fin field effect transistor, the method comprising:

(1) forming a structure comprising a projecting region on a predetermined plane of a semiconductor substrate, and a mask pattern and a gate insulating film between masks of the mask pattern on a top surface of the projecting region;

(2) forming a polysilicon film all over the structure;

(3) executing a CMP process on the polysilicon film through the mask pattern as a stopper;

(4) forming a metal film all over the polysilicon film;

(5) forming a gate electrode comprising a metal silicide layer formed by reacting the polysilicon film with the metal film;

(6) forming a mask A on the gate electrode;

(7) removing the metal film through the mask A as a mask;

(8) removing the mask pattern; and

(9) implanting impurity into the semiconductor substrate through the mask A as a mask to form a source/drain region,

wherein step (8) comprises:

forming a protect film all over the structure; and

performing an etch back process to remove the mask pattern and the protect film on the mask pattern so as to leave the mask A on the gate electrode.

7. The method of manufacturing a semiconductor device according to claim 6 , wherein the metal is W, and in step (5), a part of the polysilicon film and a part of the metal film are allowed to react with each other to silicidize the metal to form the gate electrode of a laminate structure with the W, WSi, and polysilicon film laminated in this order from above.

8. A method of manufacturing a semiconductor device comprising a Fin field effect transistor, the method comprising:

(1) forming a structure comprising a projecting region on a predetermined plane of a semiconductor substrate, and a mask pattern and a gate insulating film between masks of the mask pattern on a top surface of the projecting region;

(2) forming a polysilicon film all over the structure;

(3) executing a CMP process on the polysilicon film through the mask pattern as a stopper;

(4) forming a metal film all over the polysilicon film;

(5) forming a gate electrode comprising a metal silicide layer formed by reacting the polysilicon film with the metal film;

(6) forming a mask A on the gate electrode;

(7) removing the metal film through the mask A as a mask;

(8) removing the mask pattern; and

(9) implanting impurity into the semiconductor substrate through the mask A as a mask to form a source/drain region,

wherein the mask pattern and the mask A comprise silicon nitride.

9. The method of manufacturing a semiconductor device compositing a plurality of the Fin field effect transistors according to claim 8 , wherein in step (5), a plurality of the gate electrodes are formed, and in step (9), a plurality of the source/drain regions are formed.