| 摘要 |
PURPOSE:To enable the removal of sticking ammonia ions without staining the surface of a semiconductor wafer, by exposing the semiconductor wafer to the vapor of a saturated fluorine acid after it is rinsed by ammonia hydrogen peroxide, and by washing the same by water thereafter. CONSTITUTION:An oxide film 2, which is an insulation layer, is formed on the surface of a semiconductor wafer 1, and the oxide film 2 in a part 3 of diffusion is removed selectively. Then, a rinsing pretreatment is performed by using a rinsing solution of ammonia hydrogen peroxide. Thereby a sticking layer 4 of ammonia ions is formed on the surface of the wafer. Next, the solution of a fluorine acid is put in the bottom portion of a vessel which can be closed up, the vapor of the fluorine acid is saturated in the vessel, and the semiconductor wafer is put in this vessel, in which the vapor 5 of the fluorine acid neutralizes the sticking layer 4 of ammonia ions. This layer 4 is removed by washing the same with water thereafter. |
