Abstract: A film formation method is provided with a step for disposing a non-electroconductive long thin tube 102 in a chamber 101 in which the internal pressure thereof is adjustable, generating a plasma inside the long thin tube 102 in a state in which a starting material gas including a hydrocarbon is supplied, and forming a diamond-like carbon film on an inner wall surface of the long thin tube 102. The long thin tube 102 is disposed in the chamber 101 in a state in which a discharge electrode 125 is disposed in one end part of the long thin tube 102 and the other end part is open. An alternating-current bias is intermittently applied between the discharge electrode 125 and a counter electrode 126 provided so as to be separated from the long thin tube 102.

Abstract: A film formation method is provided with a step for disposing a non-electroconductive long thin tube 102 in a chamber 101 in which the internal pressure thereof is adjustable, generating a plasma inside the long thin tube 102 in a state in which a starting material gas including a hydrocarbon is supplied, and forming a diamond-like carbon film on an inner wall surface of the long thin tube 102. The long thin tube 102 is disposed in the chamber 101 in a state in which a discharge electrode 125 is disposed in one end part of the long thin tube 102 and the other end part is open. An alternating-current bias is intermittently applied between the discharge electrode 125 and a counter electrode 126 provided so as to be separated from the long thin tube 102.