Method for manufacturing IGBT

The invention provides a method for manufacturing an insulated gate bipolar transistor (IGBT). The IGBT with an improved latching effect is obtained by using a polycrystalline silicon layer as a mask for two times; when the polycrystalline silicon layer is used as the mask for the first time, first conductive impurity ions are injected to form a heavily doped well region; when the polycrystalline silicon layer is used as the mask for the second time, the mask is acted with a source region photo-mask together, and second conductive impurity ions are injected to form a source region; and the polycrystalline silicon layer serving as the mask for the second time is obtained by wet etching of the polycrystalline silicon layer serving as the mask for the first time. Therefore, the concentration of the well region under the source region is kept high and distributed uniformly, the problems that an inversion layer cannot be formed and the threshold value is over high because of over high concentration of a channel region are overcome, meanwhile, the mask of a P+ well layer process in the traditional process is omitted, and the method is favorable for reducing the size of unit cells and avoids the alignment problem of process mask.