Etching characteristics of fine Ta patterns with electron cyclotron resonance chlorine plasma

Next generation lithography requires masks with new structures fabricated by silicon process. We have studied etching characteristics of Ta, which is a strong candidate for absorber or scatterer patterns in NGL masks. Many groups reported Ta etching with mixture gases, but we performed Ta etching with pure chlorine chemistry and obtained a clear 0.2 /spl mu/m line and space patterns through the step etching process.