The evolution of target “race track” erosion was evaluated experimentally during the conventional DC magnetron sputtering of metal targets with different Ar gas pressure environments. At gas pressures of 0.38, 0.5, and 1.0 Pa, an aluminum or copper target was sputtered at a DC discharge power of 100 W. At time intervals of several hours, the target was taken out of the chamber and its erosion profile was measured with a height gauge. As the sputtering erosion of the target proceeded, the erosion track diameter was almost the same in all sputtering conditions, whereas the track width (full width at half maximum: FWHM) showed quite different behaviors depending on the gas pressure. At 0.38 Pa, the FWMH increased slightly with increasing sputtering time. On the other hand, at 1.0 Pa, the FWMH decreased with increasing sputtering time.
2015 The Vacuum Society of Japan