Abstract: Disclosed is a method for making a MIS transistor that a gate electrode and gate insulating film are formed on a semiconductor substrate with a channel region formed implanting an impurity of one conductivity type thereinto, which has the steps of: implanting hydrogen ions through said gate electrode and gate insulating film into said channel region under said gate electrode; ion-implanting an impurity of a conductivity type reverse to said one conductivity type self-aligned to said gate electrode to form a source/drain region; and conducting thermal treatment in an inert atmosphere or nitrogen atmosphere.