Hello

If you need an isotropic efficicient etch yo need to increase the O2 flow in your recipe. Are you using a bias voltage in your recipe? Because you must not add any bias in order to avoid any anisotropic effect.

Regards

Loraine

Hi Nick,

I can't recall a specific paper at the moment, but, plasma etching is often a combination of chemical and mechanical processes, getting a desired profile might require some 'optimisation' of the process. As Laurène Youssef points out, plasma voltage is important, and there might be some scope to adjust your etching profile with your vacuum level, a higher pressure could reduce the energy in the system and get you closer to the profile you want - this might however reduce your etch rate even further which could be partially mitigated with an increase in O2.

Good luck.

Martin