| 摘要 |
PURPOSE:To improve a patterning performance by providing a heat treatment for a polycrystalline or amorphous silicon annealed with laser or electric charge particle rays. CONSTITUTION:A polycrystal line silicon 4 is stacked on the whole surface of a substrate 1 having a field oxide film 2 and gate oxide film 3 mounted thereon. The impurity of phosphorus or arsenic and others is doped to the polysilicon 4 at the stacking process. After the polysilicon crystal 4 is annealed and is converted into a large silicon film of grain size, a heat treatment is provided in the nitrogen atomosphere at 1,000 deg.C and for 20min, for example. Thereafter, an etching is provided for the polycrystal silicon to establish a patterning. Therefore, stress increased by the annealing on the boundary surface is released through the heat treatment, as a result, an abnormally accelerated etching along the grain boundary surface can be prevented. |
