Method for reforming amorphous carbon polymer film

1. A method for reforming an amorphous carbon film as part of a deposition process thereof, comprising processes of:

(i) depositing an amorphous carbon film using a silicon- and metal-free precursor on a substrate in a reaction space until a thickness of the amorphous carbon film reaches a predetermined thickness, and then stopping the deposition process; and

(ii) annealing the amorphous carbon film by exposing the amorphous carbon film to an Ar and/or He plasma in an atmosphere substantially devoid of hydrogen, oxygen, and nitrogen,

wherein process (ii) comprises feeding Ar and/or He to the atmosphere without feeding hydrogen, oxygen, and nitrogen; and applying RF power to the atmosphere in a manner generating the Ar and/or He plasma, and

wherein process (i) is conducted by plasma-enhanced atomic layer deposition (PEALD).

2. The method according to claim 1 , wherein processes (i) and (ii) are repeated multiple times until a thickness of the amorphous carbon film reaches a desired final thickness.

3. The method according to claim 1 , wherein the predetermined thickness in process (i) is a monolayer thickness or more but 10 nm or less.

4. The method according to claim 1 , wherein the atmosphere in process (ii) is in the reaction space used in process (i).

5. The method according to claim 1 , wherein the atmosphere in process (ii) is in another reaction space different from the reaction space used in process (i).

6. The method according to claim 1 , wherein RF power is in a range of 0.06 W/cm 2 to 0.96 W/cm 2 per unit area of the substrate, and a duration of process (ii) is in a range of 2 seconds to 300 seconds.

7. The method according to claim 1 , wherein the substrate has a patterned recess or step on its surface on which the amorphous carbon film is deposited.