MANUFACTURING METHOD OF SEMICONDUCTOR APPARATUS AND SEMICONDUCTOR APPARATUS

摘要

A screen oxide film is formed on an n- drift layer (2) that is disposed on an anterior side of an n-type low-resistance layer (1), and a nitride film is formed on the screen oxide film. The nitride film is photo-etched using a first mask and thereby, a nitride shielding film (61) is formed. N-type impurity ions at a concentration higher than that of the n- drift layer are implanted through the nitride shielding film (61) from an anterior side of a semiconductor substrate and are thermally diffused and thereby, an n counter layer (7) is formed. The screen oxide film is removed. A gate oxide film (3a) is formed. A gate electrode (9) is formed on the gate oxide film (3a). P-type impurity ions are implanted from the anterior side of the semiconductor substrate using the gate electrode (9) and the nitride shielding film (61) as a mask and thereby, p- well regions (10) are formed. N-type impurity ions are implanted from the anterior side of the semiconductor substrate using the gate electrode (9) and the nitride shielding film (61) as a mask and thereby, n source regions (11) are formed.