Planar plasma etching of Mo and MoSi2using NF3gas mixtures is reported for the first time. The etch rates of Mo, MoSi2, and SiO2were determined as a function of RF current and gas pressure. The etch rate selectivities of Mo:SiO2and MoSi2:SiO2was found to be relatively constant at respectively 2-3:1 and 4-6:1 over a broad range of parameters. Diluting the NF3to 10% in Argon lowered the etch rate by a factor of 5-6. Improved line edge profile obtained with NF3etching is shown.