Patent ID: 6482701
Filing Date: 2002-11-19
Classification: H01L

Abstract:
A method of manufacturing a semiconductor device comprising:forming a trench at a surface of a semiconductor substrate by conducting an anisotropic etching, the trench having a bottom; processing a bottom of the trench including a corner portion into a concave shape having a slant surface by conducting a concave etching after forming the trench, wherein the concave etching etches the semiconductor substrate so that a diameter of the trench is gradually reduced as the concave etching advances; and rounding off the corner portion of the bottom of the trench by conducting an isotropic etching, after processing the corner portion, wherein a ratio of a horizontal etching rate with respect to a vertical etching rate of the concave etching is smaller than a ratio of the horizontal etching rate with respect to the vertical etching rate of the isotropic etching.