With High Density Plasma Sources (HDP)
it is possible to use higher plasma
densities (current densities) at lower
energies. The above SEM shows a 20 µm
deep etch in InSb. This work has been
performed at the OPT application lab
using an ICP (Inductive Coupled Plasma)
Source.

ICP layout

OPT Application lab:
sloped InSb etch at 0.4 µm/ min
with contollable profile
selectivity to SiO2 > 5 : 1

20 µm deep CMT etch

CH4/H2 /(Cl2) based chemistry for
excellent mask selectivity

Typical results
Etch rate InSb 50-100 nm/min (without Cl2)
Selectivity to PR: > 500:1
Etch rate InSbAs > 800 nm/min (with Cl2)
Selectivity to SiO2: > 8:1
Uniformity: < + 2% (2” wafer)
Smooth etched surfaces

Plasmalab System 100
with loadlock and ICP180 source