Oxford Instruments: PlasmaPro 100 ICP 180 System 100 Reactive Ion Etcher (RIE)

Reactive Ion Etching is a fabrication technique used to remove material from a substrate or device by generating a plasma containing ions and other reactive species. The substrate is usually protected by a mask to remove material only in exposed areas and pattern the sample. Once prepared, the sample is placed in a vacuum chamber, into which the gas mixture is introduced. When power is applied from an RF generator, this produces a plasma that reacts with the surface to remove material.

In traditional RIE techniques, a single DC power source applied to the sample is used to generate the plasma and provide directionality, giving rise to an anisotropic etch profile. The addition of a second ICP (Inductively Coupled Plasma) RF generator can be used to significantly increase the plasma density, although using this alone results in a more isotropic etch profile.

Further control and process customisability is afforded by the inclusion of a low frequency RF generator, gas flow rate control using MFCs, automatic process pressure control, and a temperature controlled lower electrode/sample platen with helium backing to enhance thermal contact with the wafer at vacuum.

Used in combination, these options allow us to tailor a wide range of parameters to achieve the desired results including the etch rate, chemical selectivity and etch profile, while mitigating issues such as surface damage and increased roughness.

This ICP RIE is our general use tool, with the broadest range of etch recipes supported. These include (but are not limited to) Al₂O₃, Au, graphene, graphite, h-BN, mica, MoS₂, NbTiN, polyimide, Si (both Bosch and continuous etches), SiN_x, SiO₂, and WTe₂.