PLASMA DOPING METHOD AND PLASMA DOPING APPARATUS

摘要

This invention provides a method for plasma doping that, even when plasma treatment is repeated, can realize an identical dose from a film to a silicon substrate for each time. In the method for plasma doping, a sample is mounted on a sample electrode within a vacuum vessel, and plasma is generated in a vacuum vessel to allow impurity ions in the plasma to collide against the surface of the sample and thus to form an impurity introduction layer on the surface of the sample. The method for plasma doping comprises a maintenance step of providing a vacuum vessel having an inner wall provided with a film, containing the above impurities, which functions so that the amount of the impurity introduced into the surface of the sample by sputtering by hitting the impurity-containing film, fixed onto the inner wall of the vacuum vessel, by ions in the plasma remains unchanged even when the impurity ion-containing plasma is repeatedly generated within the vacuum vessel, a step of mounting a sample on the sample electrode, and a step of applying the impurity ion-containing plasma to implant the impurity ion on into the sample and, at the same time, to introduce the impurity into the sample by sputtering from the impurity-containing film fixed onto the inner wall of the vacuum vessel.