OPT application lab:
anisotropic AlGaN/ GaN etch
stopping in the saphire substrate

OPT application lab:
anisotropic Ga etch
structure see schematic

ICP schematic

dual chamber cluster: ICP / RIE

Reactive Ion Etching
with ICP Source (13.56 MHz)
Inductive Coupled Plasma
13.56 MHz Plasma Excitation
Process chemistry: Cl based
RF driven substrate electrode

Rate : 0.15 - 0.7 µm/ min
Selectivity to SiO2 mask 8 - 10 : 1
Selectivity to Ni mask 30 : 1
Selectivity to PR mask 0.7 - 0.9 : 1
good uniformity: +/- 2% (2“)
anisotropic profile
smooth etched sidewalls suitable for
laser facet formation