The Georgia Tech Xactix Xenon Difluoride Etcher uses xenon difluoride gas sent through a showerhead to isotropically dry etch silicon, germanium, and molybdenum. It can process pieces up to 4" wafers and generates relatively rough isotropically etched features.

Vendor-specified system features

• Excellent selectivity SiO2 :Si (1000:1), good selectivity to PR
• Potential to etch very small devices (30nm)
• Etch does not attack Bosch passivation layer – can switch between tools and still protect trench walls

Materials etched

• Si, poly-Si

Acceptable masks

• PR, SiO2 , Si3N4

Gases

• XeF2

Substrate

• 1 die - 150mm wafer (specialized chuck)