Varying O2 plasma exposure
shifts between Pt and PtO2 .

Purely thermal Pt ALD growth is hard to achieve
as no Pt-O bonds will form. Remote plasma ALD
can be used to create a seed layer.
Once the Pt ALD process started, it can be continued
with either plasma or thermal ALD at similar rates.

"Flex AL" for
Atomic Layer Deposition

Metal precursor: MeCpPtMe3
Delivery Method: bubbled with argon
Non-metal precursor: O2 thermal or plasma

Results:
The O2 plasma significantly reduces
the nucleation delay.

The initial thermal Pt nucleation process
is pressure dependent.
Radical assisted ALD results in a
much shorter nucleation delay.

H2 plasma can reduce PtO2 to Pt and
lowers temperature range of Pt deposition.

- 0.45 Å/cycle
- 7-8 sec cycle time
- Deposition rate ~ 0.3 - 0.4 nm /min
                             ~ 18 - 24 nm /h
- Resistivity ~13 µOhm cm

with kind permission of TU Eindhoven

DOWNLOAD white paper on Pt ALD (2011)

"OpAL" for
Atomic Layer Deposition

Why remote plasma ALD ?

A "remote plasma" makes sure, the substrates
are NOT in contact with the plasma !

The remote plasma just cracks molecules,
so that very reactive species can be used for
the growth process.

Such reactive species often enable a very
efficient plasma preclean of the substrates,
lead to cleaner films and lower the deposition
temperature.

ALD schematic
valve between remote ICP source
and chamber,
spectroscopic ellipsometry optional