Discharge and Deposition Characteristics of High-Power Impulse Magnetron Sputtering Using Various Target Materials

The discharge and deposition characteristics of high-power impulse magnetron sputtering using various target materials with different sputtering yields (Cu, Cr, Ti, and C) were analyzed by a plasma global model. The experimental discharge voltages and currents of various target materials were used as the input parameters of the model. The analysis reveals that the ionization fraction of the sputtered species decreases as increasing the sputtering yield, due to the electron temperature was reduced through the cooling effect of sputtered species. However, as the sputtering yield increases, the plasma density under a given discharge power density is increased and the self-sputtering runaway can be fully developed, resulting in a higher fraction of ion density in the form of metal ions in the ion deposition flux. For some high-sputtering yield materials, such as Cu and Cr, this fraction can be up to 95%.