MANUFACTURING METHOD FOR SEMICONDUCTOR DEVICE

摘要

A p + collector layer is provided in a surface layer of the rear surface of a semiconductor substrate which will be an n- drift layer and an n + field stop layer including a plurality of n + layers is provided in a region which is deeper than the p + collector layer formed on the rear surface side. A front surface element structure is formed on the front surface of the semiconductor substrate and then protons are radiated to the rear surface of the semiconductor substrate at an acceleration voltage corresponding to the depth at which the n + field stop layer is formed (Step S5). Then, a first annealing process is performed at an annealing temperature corresponding to the proton irradiation to change the protons into donors, thereby forming a field stop layer (Step S6). Then, annealing is performed using annealing conditions suitable for the conditions of a plurality of proton irradiation processes to recover each crystal defect formed by each proton irradiation process. Therefore, it is possible to form a plurality of regions with high carrier concentration. In addition, it is possible to improve poor electrical characteristics, such as an increase in leakage current.