TRENCH SIDE-WALL DOPING METHOD USING OXIDATION AND MITRATE WALL AND ITS ELEMENT

摘要

A dopping method of a trench side-wall is characterized by forming the first trench on the silicon wafer and depositing the oxide wall on the trench wall, depositing the nitride wall on the oxide wall and the mask layer, etching and removing the nitride layer and the oxide layer, forming the second trench on the inner side of the first trench, and forming the dopping region of P+ or N+ impurities on the second trench wall. The method is useful for the mfr. of the semiconductor element comprising the dopping structure of the trench side-wall.