SILICON EPITAXIAL WAFER MANUFACTURING METHOD AND SILICON EPITAXIAL WAFER

摘要

The angular section for aligning the normal vector alpha of a major surface (MP) of a substrate with the normal vector beta of the inner side along the length of a trench (11) filled with a filling epitaxial layer (3) by moving the normal vector alpha by a minimum rotational angle is defined as a transition surface normal angle region theta. An area where an opening edge of the trench along the length is formed is assumed as a transition surface area where the normal vector continuously changes through the transition surface normal angle region theta. The Miller index (h1k1l1) of the substrate major surface (2) and the Miller index (h2k2l2) of the inner side (WP) of the trench (11) along the length are so specified that the normal vectors of all the {111} surfaces of the silicon monocrystalline substrate (2) are out of the transition normal angle region theta. Thus, a silicon epitaxial wafer manufacturing method can be provided in which constriction of the opening of the trench due to the overgrowth of the filling epitaxial layer hardly occurs and the residues such as voids in the filling epitaxial layer in the trench can be effectively suppressed even if the aspect ratio of the trench is large.