A method for producing a semiconductor device includes implanting protons from a rear surface of a semiconductor substrate of a first conductivity type, and after the implanting protons, forming a first semiconductor region of the first conductivity type having a impurity concentration higher than that of the semiconductor substrate by performing an annealing process for the semiconductor substrate in an annealing furnace. The forming a first semiconductor region includes substituting oxygen gas for nitrogen gas in a normal pressure atmosphere, thereby reducing a partial pressure of the oxygen in the annealing furnace, and after the subtracting oxygen gas, performing the annealing process in the annealing furnace with a hydrogen gas atmosphere in a range of 300° C. to 450° C. The hydrogen gas atmosphere includes a volume concentration of hydrogen in a range of 6% to 30%.