Patent ID: 8163140

Claim:
A method for reactive sputtering using a reactive sputtering apparatus including a sputtering vaporization source provided with a metal target disposed in a vacuum chamber, a sputtering power source to drive the sputtering vaporization source, and an introduction mechanism to introduce an inert gas for sputtering and a reaction gas for forming a compound with sputtered metal into the vacuum chamber, comprising the steps of: performing reactive sputtering film formation on a substrate disposed in the vacuum chamber, wherein a plasma emission is generated forward of the sputtering vaporization source; performing target voltage control to set a target voltage Vs for the sputtering vaporization source based on the spectrum of the plasma emission generated forward of the sputtering vaporization source; and performing constant-voltage control to control the voltage of the sputtering power source to be the target voltage Vs by comparing an actual output voltage of the sputtering power source to the target voltage Vs, and issuing an output voltage control command based on a difference between the actual output voltage of the sputtering power source and the target voltage Vs, wherein a control speed of the constant voltage control is higher than a control speed of the target voltage control, wherein the control response time Tv of the constant-voltage control is within the range of 0.1 milliseconds to 0.1 seconds and the control response time To of the target voltage control is within the range of 0.1 seconds to 60 seconds.