| 摘要 |
PURPOSE:To obtain a uniform and narrow trench by a method wherein a semiconductor film is formed on side walls of pillar-shaped parts which have been left after a selective etching operation of an impurity-containing insulating layer on a substrate, a semiconductor layer is grown between the pillar-shaped parts, and an impurity is diffused to a semiconductor growth layer from the pillar-shaped parts so that the pillar-shaped parts can be removed. CONSTITUTION:An insulating layer 11 containing an impurity is formed on a substrate 1; this insulating layer is etched selectively to leave pillar-shaped parts 11; a semiconductor film 12 covering the pillar-shaped parts is formed. This semiconductor film 12 is etched anisotropically to leave the semiconductor films 12 on side walls of the pillar-shaped parts 11; a semiconductor layer 13 is grown between the pillar-shaped parts; an impurity 14 is diffused to the semiconductor growth layer 13 from the pillar-shaped parts; after that, the pillar-shaped parts 11 are removed, In this manner, trenches are not dug in the substrate, but the insulating films to become the trenches are left to be pillar-shaped; accordingly, it is easy to control a depth of the trenches. By this setup, the uniformly shaped and narrow trenches can be formed. |
