PURPOSE: To provide the recording medium having high sensitivity, good recording sensitivity and long life by adding NH3 to gases in the case of executing sputtering with a metal, metalloid or semiconductor as a cathode in a gaseous hydrocarbon or atmosphere mixture composed of the gaseous hydrocarbon and rare gas.

CONSTITUTION: The NH3 is added to the gases in the method of forming the information recording medium 3 by executing the sputtering with the metal, metalloid or semiconductor as the cathode in the gaseous hydrocarbon or the atmosphere mixture composed of the gaseous hydrocarbon and the rare gas. The gradient of the optical recording sensitivity curve of the recording film 2 such as metal is then less steepened by the nitrogen generated by cracking of the gaseous NH3 and the metal, etc., are hydrogenated by hydrogen and are thereby stabilized. In addition, the resultant product of the cracking (C-H fragment) formed by cracking of the gaseous CH4 during sputtering discharge exists in the recording film and, therefore, the recording film has the excellent resistance to moisture and oxidation. The long-life information recording medium having the high density, the high sensitivity and the long life is thereby obtd.