Semiconductor device and method of manufacture thereof

A method for manufacturing a semiconductor device comprising:

• forming a semiconductor region;
• forming a gate insulation film over the semiconductor region;
• forming a gate electrode over the gate insulation film, wherein the gate electrode comprises metal material;
• forming an oxide layer over and in contact with the gate electrode;
• first doping an impurity element into the semiconductor region to form a low-concentration impurity region in contact with a channel-forming region;
• after first doping, second doping an impurity element into the semiconductor region to form a high-concentration impurity region in contact with the low-concentration impurity region;
• after second doping, removing a portion of the gate insulation film so as to expose at least a side surface of the semiconductor region;
• forming a metal film so as to cover at least the side surface of the semiconductor region and a top surface of the gate electrode, wherein the metal film is provided over the gate electrode with the oxide layer interposed therebetween;
• and
• forming a metal silicide layer over the semiconductor region.

A method for manufacturing a semiconductor device comprising:

• forming a semiconductor region;
• forming a gate insulation film over the semiconductor region;
• forming a gate electrode over the gate insulation film, wherein the gate electrode comprises metal material;
• forming an oxide layer over and in contact with the gate electrode, the oxide layer being in contact with a side surface of the gate electrode;
• doping an impurity element into the semiconductor region to form a low-concentration impurity region in contact with a channel-forming region;
• after doping, removing a portion of the gate insulation film so as to expose at least a side surface of the semiconductor region;
• after doping, activating the impurity element by heating;
• forming a metal film so as to cover at least the side surface of the semiconductor region and a top surface of the gate electrode, wherein the metal film is provided over the gate electrode with the oxide layer interposed therebetween;
• and
• forming a metal silicide layer over the semiconductor region,
• wherein a part of the low-concentration impurity region overlaps with the gate electrode.

A method for manufacturing a semiconductor device comprising:

• forming a semiconductor region;
• forming a gate insulation film over the semiconductor region;
• forming a gate electrode over the gate insulation film, wherein the gate electrode comprises metal material;
• forming an oxide layer over and in contact with the gate electrode, the oxide layer being in contact with a side surface of the gate electrode;
• first doping an impurity element into the semiconductor region to form a low-concentration impurity region in contact with a channel-forming region;
• after first doping, second doping an impurity element into the semiconductor region to form a high-concentration impurity region in contact with the low-concentration impurity region;
• after second doping, removing a portion of the gate insulation film so as to expose at least a side surface of the semiconductor region;
• forming a metal film so as to cover at least the side surface of the semiconductor region and a top surface of the gate electrode, wherein the metal film is provided over the gate electrode with the oxide layer interposed therebetween;
• and
• forming a metal silicide layer over the semiconductor region.