OPT application lab:
anisotropic etch of 1 µm SiN (PR mask not removed)

Plasmalab 80 Plus

RIE technology

OPT application lab:
anisotropic RIE etch of 2.2 µm SiN (PR mask not removed)

SiN can be etched isotropic at high rate
(RIE up to 500 nm/ min, ICP > 1 µm/ min) or
anisotropic by RIE as well as ICP-RIE by sidewall polymerisation.

• anisotropic etch: RIE 50 - 150 nm/ min*,  ICP ca 0.5 µm/ min
• maximum etch rates dependent on mask and temperature limitations
• uniformity   ± 2 - 4  % for the anisotropic etch

*High rates require Helium cooling, if a PR mask is used.
Even higher rates are possible with hard masks.