METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE, SUBSTRATE PROCESSING METHOD AND SUBSTRATE PROCESSING DEVICE

PROBLEM TO BE SOLVED: To provide a method for manufacturing a semiconductor device, a substrate processing method and a substrate processing device, capable of suppressing a leakage current of an insulating film formed.SOLUTION: A method for manufacturing a semiconductor device includes: supplying a first processing gas containing a first element to be independently a solid to a processing chamber storing a substrate under a temperature condition generating a CVD reaction, to form a first layer containing the first element on the substrate (first layer forming step); supplying a second processing gas containing a second element not to be independently a solid to the processing chamber to allow the second processing gas to react with the first layer, to form a second layer containing the first element and the second element (second layer forming step); and one or more times repeating one cycle including one time of the first layer forming step and one time of the second layer forming step, to form a thin film containing the first element and the second element each having a predetermined film thickness.