Patent ID: 8821990

Claim:
A method for forming, inside a treatment chamber, a DLC film that covers at least a portion of a surface of a substrate, the DLC film-forming method comprising: a pretreatment process that is executed in a reduced pressure state of a predetermined treatment pressure generated by a low-vacuum pump, and that supplies Ar ions and H ions to the surface of the substrate by applying direct-current pulse voltage to the substrate, and generating plasma in an atmosphere that contains argon gas and hydrogen-based gas inside the treatment chamber; and a DLC deposition process that is executed after the pretreatment process in the reduced pressure state, and that forms a deposition layer of DLC on the surface of the substrate after the pretreatment process is executed, by applying direct-current pulse voltage to the substrate, and generating plasma in an atmosphere inside the treatment chamber, wherein: in the pretreatment process and the DLC deposition process, a treatment time of both of the processes, the predetermined treatment pressure in both of the processes, or a frequency, duty ratio, or voltage value of the direct-current pulse voltage applied to the substrate in both of the processes, is set such that a temperature of the substrate becomes equal to or less than 300° C.; the atmosphere inside the treatment chamber in the pretreatment process contains carbon-based gas and nitrogen-based gas; and the pretreatment process includes a first process in which the argon gas and the hydrogen-based gas contained in the atmosphere are at higher concentrations than the carbon-based gas and the nitrogen-based gas, and a second process that is executed following the first process, and in which the carbon-based gas and the nitrogen-based gas contained in the atmosphere are at higher concentrations than the argon gas and the hydrogen-based gas.