| 摘要 |
PURPOSE:To diffuse a sheet resistor between lots of a wafer with less irregularity by exposing and using fresh surface at every predetermined number of times of a solid diffusion source. CONSTITUTION:As the number of uses of a solid diffusion source increases, the volatile amount of impurity decreases. Accordingly, the sheet resistance rhos of the wafer will decreases. When the surface of the solid diffusion source is polished when it is lowered to the prescribed degree to expose new surface and reuse it, it is so diffused as to approximately maintain the sheet resistance rhos of the wafer always constantly. |
