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NanoFab Tool: Unaxis 790 Reactive Ion Etcher 1

Photograph of the Unaxis 790 reactive ion etcher.

The Unaxis 790 reactive ion etcher (RIE) is a general purpose parallel plate plasma etching system which uses ionized fluorocarbon gases and oxygen to etch polymer and dielectric materials. The large chamber can accommodate substrates ranging from 200 mm diameter wafers down to small pieces.


  • Radio frequency (RF) power source: up to 500 W at 13.56 MHz.
  • Electrode temperature range: 0 °C to 70 °C.
  • Unique process gases: trifluormethane (CHF3), tetrafluoromethane (CF4), sulfur hexafluoride, nitrous oxide (N2O), and oxygen.
  • Reactive ion etching of silicon, silicon oxide and silicon nitride.

Usage Information

Supported Sample Sizes

  • Maximum wafer diameter: 200 mm (8 in).
  • Small pieces supported: Yes.

Typical Applications

  • Anisotropic thin film etching.
  • Photoresist descum.
  • Silicon nitride membrane fabrication.
Created June 22, 2014, Updated December 4, 2019