An insulated gate bipolar transistor (IGBT) manufacturing method comprises the following steps: providing a semiconductor substrate of a first conducting type, the semiconductor substrate having a first major surface and a second major surface (100); forming a field-stop layer of a second conducting type on the first major surface of the semiconductor substrate (200); growing an oxide layer on the field-stop layer (300); removing the oxide layer from the field-stop layer (400); forming an epitaxial layer on the field-stop layer from which the oxide layer has been removed; and then manufacturing an IGBT on the epitaxial layer (600). Before regular manufacturing of an IGBT, the surface defects of a substrate material are eliminated as many as possible before epitaxy is formed, and the quality of an epitaxial layer is improved, thereby improving the quality of the whole IGBT.