Semiconductor device and fabrication method therefor, capacitive element and fabrication method therefor, and MIS type semiconductor device and fabrication method therefor

A capacitive element comprising:

• a first metal layer;
• a silicon nitride film formed on the first metal layer with the use of a mixed gas that includes mono-silane gas, hydrogen gas, and nitrogen gas, by a plasma CVD apparatus, under a condition that a flow rate of the hydrogen gas is 0.2 percent to 5 percent to an overall flow rate;
• and
• a second metal layer formed on the silicon nitride film.

A MIS type semiconductor device comprising:

• an operating layer made of a semiconductor;
• a gate insulating film made of a silicon nitride film formed on the operating layer with the use of a mixed gas that includes mono-silane gas, hydrogen gas, and nitrogen gas, by a plasma CVD apparatus, under a condition that a flow rate of the hydrogen gas is 0.2 percent to 5 percent to an overall flow rate;
• a gate electrode formed on the gate insulating film;
• and
• a source electrode and a drain electrode formed on the operating layer to interpose the gate electrode therebetween.

A fabrication method of a semiconductor device comprising:

• forming a silicon nitride film on a layer to be selectively processed with the use of a mixed gas that includes mono-silane gas, hydrogen gas, and nitrogen gas, in a plasma CVD apparatus, under a condition that a flow rate of the hydrogen gas is 0.2 percent to 5 percent to an overall flow rate;
• forming a predetermined mask pattern on the silicon nitride film;
• and
• selectively processing the layer with the predetermined mask pattern.