AMORPHOUS CARBON FILM FOR DRILLING TOOL AND DRILLING TOOL

PROBLEM TO BE SOLVED: To provide an amorphous carbon film for a drilling tool having extremely excellent practicality capable of improving breaking resistance and coating the drilling tool at a moderate price. SOLUTION: The amorphous carbon film for the drilling tool is formed on a base material. When Raman scattering spectroscopic analysis is performed thereon using a laser beam of 532 nm wave length, a value of ratio ID/IGof peak strength IDin the vicinity of Raman shifting 1,330-1,360 cm-1to peak strength IGin the vicinity of Raman shifting 1,530-1,560 cm-1differs depending on a position in the circumferential direction on the outer peripheral part of the tool. When the maximum value of the ID/IGin the circumferential direction is set as (ID/IG)maxand the minimum value is set as (ID/IG)min, the relationship of (ID/IG)min