Method of manufacturing semiconductor device

1. A method of manufacturing a semiconductor device, comprising:

forming a first gate electrode in a first region of a semiconductor substrate and forming a second gate electrode in a second region of the semiconductor substrate;

forming a first sidewall spacer along a lateral wall of the first gate electrode and forming a second sidewall spacer along a lateral wall of the second gate electrode;

forming an oxide film so as to cover the semiconductor substrate, the first gate electrode, the second gate electrode, the first sidewall spacer and the second sidewall spacer;

forming a resist above the oxide film so as to cover the first region of the semiconductor substrate;

removing the oxide film in the second region of the semiconductor substrate by etching the oxide film with the resist serving as a mask;

removing the resist; and

executing a plasma process by using a gas containing chlorine with respect to the semiconductor substrate and the oxide film in the first region of the semiconductor substrate to increase etch resistance of the oxide film against hydrofluoric acid.

2. The method of manufacturing the semiconductor device according to claim 1 , further comprising removing the oxide film remaining in the second region of the semiconductor substrate by rinsing the semiconductor substrate.

3. The method of manufacturing the semiconductor device according to claim 2 , further comprising:

forming a recess in a surface of the semiconductor substrate in the second region of the semiconductor substrate; and

forming a silicon germanium within the recess.

4. The method of manufacturing the semiconductor device according to claim 1 , wherein the oxide film is formed by using a raw gas containing TEOS, BTBAS or TDMA.

5. A method of manufacturing a semiconductor device, comprising:

forming a first gate electrode in a first region of a semiconductor substrate and a second gate electrode in a second region of the semiconductor substrate;

forming a first sidewall spacer on a sidewall of the first gate electrode and a second sidewall spacer on a sidewall of the second gate electrode;

forming a source region and a drain region in the first region of the semiconductor substrate;

forming a silicon oxide film above the semiconductor substrate, the first gate electrode, the second gate electrode, the first sidewall spacer and the second sidewall spacer;

removing the silicon oxide film in the second region; and

executing a plasma process using a gas containing chlorine to the semiconductor substrate and the silicon oxide film in the first region to increase etch resistance of the silicon oxide film against hydrofluoric acid.

6. The method of manufacturing the semiconductor device according to claim 5 , further comprising:

rinsing the semiconductor substrate after the plasma process.

7. The method of manufacturing the semiconductor device according to claim 6 , wherein the rinsing uses a fluid containing a hydrofluoric acid.

8. The method of manufacturing the semiconductor device according to claim 5 , further comprising:

forming a recess in the second region of the semiconductor substrate after the plasma process; and

forming a silicon germanium in the recess.

9. The method of manufacturing the semiconductor device according to claim 5 , wherein the oxide film is formed by using a raw gas containing TEOS, BTBAS or TDMA.

10. The method of manufacturing the semiconductor device according to claim 8 , further comprising:

removing the oxide film in the first region after forming the silicon germanium;

forming a silicide layer on the first gate electrode, the second gate electrode, the silicon germanium, the source region and the drain region;

forming an insulating film above the silicide layer;

forming a hole in the insulating film;

forming a conductive layer in the hole.