SUBSTRATE TREATMENT METHOD

When it is intended to remove a resist film relying only on the decomposition activity of ozone, there is a problem that the time of period required for the treatment is prolonged or a problem that, although the detachment of the resist film is promoted by swelling the resist film, the degree of progression of the swelling still has much room for improvement. The purpose of the present invention is to solve these problems and provide a substrate treatment method whereby it becomes possible to remove a resist film from a substrate within a short time while reducing the burden of the treatment of liquid waste. The substrate treatment method comprises the steps: bringing a resist film on a substrate (901) into contact with an ozone-containing aqueous solution (920); and bringing a part (P1) of the resist film which has been already in contact with the ozone-containing aqueous solution (920) into contact with an ammonia-containing aqueous solution (930) that contains ammonia at a higher concentration compared wit