Method of manufacturing a semiconductor device having a laminated structure comprising a boron-doped silicon germanium film and a metal film

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

forming a sacrificial interlayer insulating film over a substrate;

forming a plurality of cylinder holes in the sacrificial interlayer insulating film positioned in each of a memory cell forming region and a compensation capacitance forming region having different planar surface areas;

forming a plurality of lower electrodes in the cylinder holes, respectively;

removing the sacrificial interlayer insulating film so that each of the lower electrodes includes an inner surface and an outer surface;

forming a capacitance insulating film on the inner and outer surfaces of each of the lower electrodes;

forming an upper electrode on the capacitance insulating film, thereby a memory cell capacitor is formed in the memory cell forming region and a compensation capacitance is formed in the compensation capacitance forming region, respectively;

forming at least a metal film as a plate electrode to cover the upper electrode; and

performing a selective etching on the plate electrode to remove respective portions of the plate electrode which are formed over a region other than the memory cell forming region and the compensation capacitance forming region;

wherein the memory cell capacitor and the compensation capacitance have a same structure, and are simultaneously formed by a same process.

2. The method according to claim 1 , wherein the metal film is a tungsten film.

3. The method according to claim 1 , wherein a total thickness of the boron-doped silicon germanium film and the metal film is in a range of 120 to 350 nm.

4. The method according to claim 3 , wherein a thickness of the metal film is in a range of 20 to 250 nm.

5. The method according to claim 1 , further comprising forming a mask film over the metal film, the selective etching being performed by use of the mask film, and the forming the mask film comprising:

forming a photoresist film by spin coating over the metal film; and

patterning the photoresist film by lithography to form the mask film.

6. The method according to claim 5 , wherein the performing the selective etching comprises:

partially etching the metal film using the mask film as a mask; and

etching the boron-doped silicon germanium film using a remaining portion of the metal film as a mask.

7. The method according to claim 1 , further comprising forming a boron-doped silicon germanium film before forming the metal film.

8. The method according to claim 7 , further comprising forming an adhesive layer on the boron-doped silicon germanium film before forming the metal film.

9. The method according to claim 8 , wherein the adhesive layer is a boron-doped silicon film that is substantially free from germanium.

10. The method according to claim 9 , further comprising forming a mask film over the metal film, the selective etching being performed by use of the mask film, and the forming the mask film comprising:

forming a photoresist film by spin coating; and

patterning the photoresist film by lithography to form the mask film.

11. The method according to claim 10 , wherein the performing the selective etching, comprises:

partially etching the metal film using the mask film as a mask; and

etching the boron-doped silicon film and the boron-doped silicon germanium film using a remaining portion of the metal film as a mask.