PURPOSE: To realize stable sputtering which is free from abnormal discharge, by forming a mass of material in such a way that the mass is made symmetrical about the axis of rotation and its meridian is formed by a curve higher than quadratic having no inflection point, and then, its base is made perpendicular to the axis of rotation.
CONSTITUTION: The mass of material 4 of a sputtering target is symmetrical about the axis of rotation and its meridian is formed by a curve higher than quadratic having no inflection point, and then, its base is perpendicular to the axis of rotation. In this case, the upper part of the mass 4 is subjected to sputtering, but the lower part has no relation with sputtering. That is to say, when the sputtering target are densely packed at the cylindrical part, sneaking of an electric field 3 hardly occurs and sputtering from a copper plate can be avoided, since the hollow part becomes extremely long. The upper part of the mass 4 has a semispherical dome like shape and the lower part has a cylindrical shape. Since no abnormal discharge takes place because no inflection point exists when such a shape is used, stable sputtering can be performed.
KODERA KOUICHI
OOTA TAKEO
