Method for forming impurity region of vertical transistor and method for fabricating vertical transistor using the same

摘要

A method for forming an impurity region of a vertical transistor includes forming an impurity ion junction region within a semiconductor substrate, and forming a trench by etching the semiconductor substrate in which the impurity ion junction region is formed. The etching process is performed to remove a portion of the impurity ion junction region, so that a remaining portion of the impurity ion junction region is exposed to a lower side wall of the trench to serve as a buried bit line junction region.

主权项

1. A method for forming an impurity region of a vertical transistor, comprising:
forming a preliminary trench by etching the semiconductor substrate; forming an impurity ion junction region in the semiconductor substrate by performing an ion implantation process on the semiconductor substrate exposed by the preliminary trench; forming a material layer and filling the material layer in the preliminary trench by using a material which is substantially equal to a material of the semiconductor substrate; and forming a trench by etching the semiconductor substrate in which the impurity ion junction region is formed, wherein the etching for forming the trench is performed to remove a portion of the impurity ion junction region, so that a remaining portion of the impurity ion junction region is exposed to a lower side wall of the trench to serve as a buried bit line junction region, and wherein the forming of the material layer is performed by an epitaxial growth process.