Method for manufacturing semiconductor device

A method for manufacturing a semiconductor device, comprising:

• a first step of forming a gate insulating film on a semiconductor substrate;
• a second step of forming a semiconductor layer made of amorphous silicon or polycrystalline silicon on the gate insulating film;
• a third step of implanting a group III or V impurity ion into a gate electrode forming region of the semiconductor layer so as to form an amorphized ion implantation region in the gate electrode forming region;
• a fourth step of, after the third step, forming an insulating film on the semiconductor layer at a temperature at which the ion implantation region is not crystallized;
• after the fourth step in which the insulating film is being formed, a fifth step of annealing the semiconductor layer in a non-oxidizing atmosphere so as to activate the impurity ion;
• and
• a sixth step of, after the fifth step, patterning the gate electrode forming region of the semiconductor layer so as to form a gate electrode from the semiconductor layer.

A method for manufacturing a semiconductor device, comprising:

• a first step of sequentially forming a gate insulating film and a gate electrode on a semiconductor substrate made of silicon;
• a second step of implanting a group III or V impurity ion onto the semiconductor substrate using the gate electrode as a mask so as to form an ion implantation region in the semiconductor substrate;
• a third step of forming an insulating film across an entire upper surface of the semiconductor substrate including the gate electrode at a temperature at which the ion implantation region is not crystallized;
• and
• after the third step in which the insulating film is being formed, a fourth step of annealing the semiconductor substrate in a non-oxidizing atmosphere so as to activate the impurity ion, thereby forming an impurity diffusion layer in a region of the semiconductor substrate beside the gate electrode.

A method for manufacturing a semiconductor device, comprising:

• a first step of sequentially forming a gate insulating film and a gate electrode containing silicon on a semiconductor substrate made of silicon and having a first region and a second region;
• a second step of implanting a group III or V impurity ion onto the semiconductor substrate using the gate electrode as a mask so as to form an amorphized ion implantation region in the semiconductor substrate;
• a third step of forming an insulating film across an entire upper surface of the semiconductor substrate including the gate electrode at a temperature at which the ion implantation region is not crystallized;
• after the third step in which the insulating film is being formed, a fourth step of annealing the semiconductor substrate in a non-oxidizing atmosphere so as to activate the impurity ion, thereby forming an impurity diffusion layer in a region of the semiconductor substrate beside the gate electrode;
• a fifth step of, after the fourth step, removing a portion of the insulating film that is included in the first region and that is above the gate electrode or the impurity diffusion layer;
• and
• a sixth step of, after the fifth step, depositing a metal film across an entire upper surface in the first region and the second region and subjecting the deposited metal film to a heat treatment so as to form a metal silicide film along an interface between the metal film and the gate electrode and an interface between the metal film and the impurity diffusion layer in the first region.