ABSTRACT
Doped impurity atoms diffuse during doping thermal treatment and the post thermal treatments such as thermal oxidation and annealing. To realize the small size transistor in ultra large scale integrated circuits, control or suppression of the dopant impurity diffusion is necessary. The ion implantation is accompanied by high temperature annealing, which repairs the physical damage. This high temperature process enlarges the impurity profile. To form a uniform diffused layer at the silicon surface of a three-dimensional structure such as a trench capacitor, not the ion implantation but a doped silicate glasses such as arsenic silicate glass or phospho-silicate glass is effective. The impurity atom kicks out the neighboring atom in the lattice site to the next interstitial position. The lattice vibrations may be represented as a statistical distribution of thermal energy among the atoms of the crystal. In a sample structure the surface of silicon crystal may have an effect on generation or annihilation of point defect.
