Reactive etching of platinum-manganese using a pulse-time-modulated chlorine plasma and a H₂ plasma post-etch corrosion treatment

The highly anisotropic and corrosion-less etching of a PtMn thin film using a pulse-time-modulated (TM) chlorine electron-cyclotron-resonance plasma was discussed. The PtMn etching rate was found to considerably increase using TM plasma, when compared with conventional continuous-wave plasma. It was also observed that the formation of etching residues and post-etch corrosion products was reduced by increasing the pulse-off time of the TM plasma. It was thus concluded that the combination of TM chlorine plasma etching and the hydrogen-plasma post-exposure treatment can successfully pattern highly anisotropic vertical etched profiles with sub-micron width and no critical-dimension loss.