Simulating method of ion implantaion and method for manufacturing semiconductor device

A method for manufacturing a semiconductor device, comprising:

• forming a gate electrode over a semiconductor substrate with a gate insulating film therebetween;
• forming an amorphous layer in a surface layer of the semiconductor substrate by ion-implanting a first impurity into the semiconductor substrate on both sides of the gate electrode under a first condition;
• forming an impurity diffusion region by ion-implanting a second impurity into the semiconductor substrate on both sides of the gate electrode under a second condition that a peak depth of the impurity is within the thickness of the amorphous layer;
• and
• activating the second impurity by heating the semiconductor substrate,
• wherein, ion-implanting the first impurity further comprising:
• calculating an integral value Φa/c by integrating a concentration distribution of the first impurity from a thickness d0 of an amorphous layer to infinite, where the amorphous layer being formed in a test crystalline substrate by ion-implanting the first impurity into the test crystalline substrate under a test condition;
• acquiring a form parameter of a concentration distribution of the first impurity that is to be obtained by the first condition, by referring to a database in which the form parameter of the concentration distribution of the first impurity is stored so as to correspond to a condition of ion implantation;
• creating a distribution function that approximates the concentration distribution of the first impurity by using the acquired form parameter, and
• obtaining such a depth da that an integral value obtained by integrating the distribution function from the depth da to infinite is equal to the integral value Φa/c, and specifying that a thickness of the amorphous layer formed in the semiconductor substrate is the depth da.

A method for manufacturing a semiconductor device, comprising:

• forming a gate electrode over a semiconductor substrate with a gate insulating film interposed therebetween;
• forming an impurity diffusion region by ion-implanting an impurity into the semiconductor substrate on both sides of the gate electrode;
• and
• activating the impurity by heating the semiconductor substrate,
• wherein, ion-implanting the impurity further comprising:
• calculating an integral value Φa/c by integrating a concentration distribution of the impurity from a thickness d0 of an amorphous layer to infinite, where the amorphous layer being formed in a test crystalline substrate by ion-implanting the impurity into the test crystalline substrate under a test condition;
• acquiring a form parameter of an impurity concentration distribution that is to be obtained by a condition of the ion-implantation of forming the impurity diffusion region, by referring to a database in which the form parameter of the impurity concentration distribution is stored so as to correspond to a condition of ion implantation;
• creating a distribution function that approximates the impurity concentration distribution by using the acquired form parameter, and
• obtaining such a depth da that an integral value obtained by integrating the distribution function from the depth da to infinite is equal to the integral value Φa/c, and specifying that a thickness of an amorphous layer formed in the semiconductor substrate at the time of forming the impurity diffusion region is the depth da.