Aluminium Oxide Deposition (Al2O3)

OpAL (ALD)
Ionfab300 (Ion Beam)
Optofab3000 (Ion Beam)

Al2O3 plasma and thermal ALD using OpALTM

Process Benefits:

Low temperature ALD down to 25 ºC is enabled by the use of O2 plasma; this is not practical using thermal H2O processes.
True self-limiting ALD behaviour

Growth rate per cycle (GPC) measured by spectroscopic ellipsometry and plotted against TMA dosage time.
Highly repeatable process
Highly conformal deposition

Applications:

Medium-k dielectric
Wear resistant coating
Barrier layer

Process Details:

	Plasma	Thermal
Precursors	TMA	TMA, H2O
Plasma gases	O2
Purge gases	N2 or Ar	N2 or Ar
Bubbler gas	N/A	N/A
Delivery method	Vapour draw	Vapour draw
Precursor dose control	Fast-pulse ALD valve	Fast-pulse ALD valve
Deposition temp.	25ºC - 400ºC	125ºC - 400ºC
Cycle time	< 4 seconds	< 2 seconds
Thickness per cycle	~ 1.05 Å/cycle (saturated dose)	~ 0.8 Å/cycle (saturated dose)
Thickness uniformity1 100 mm 150 mm 200 mm	< ±1.0% (5mm excl zone) < ±1.5% (7mm excl zone) < ±2.0% (10mm excl zone)	< ±1.0% (5mm excl zone) < ± 2.0% (7mm excl zone) < ±2.5% (10mm excl zone)
Repeatability1	< ±1%	< ±1%
Carbon impurity		< 3 at% @ > 200ºC
Refractive Index	1.63	1.62 Al:O 2:3 (by RBS and AES)

Notes:

1. Uniformity and repeatability defined as ±[(max‑min)/(2*mean)]*100%
2. Post forming gas anneal at 425°C
3. All specifications are based on silicon substrate

Aluminium oxide (Al2O3) Ion Beam deposition/Reactive Ion beam Deposition IBD/RIBD

Ionfab 300Plus

Al2O3 IBD/RIBD in the Ionfab300Plus (LC)

Process Specification:

Pre-clean: 35cm source can pre-clean up to 200mm substrates
Deposition Gases: Ar, O2
Up to 200mm wafers
Summary performance data:

Chamber base pressurea	<3e-7 Torr
Load lock base pressureb	<1e-5 Torr

a. After 12 hours bake out at 80˚C.
b. Load lock pumps down to 6E-5Torr in less than three minutes. It takes less than five minutes from sample loading i.e. from the load lock to process platen with load lock pump down sequence.

Process specification

1. Al2O3 deposition with rotation and adjustable tilt.

Parameter/Process	Al2O3 dep	Al2O3dep
Target (size=200mm)	Al	Al2O3
Gas chemistry	Ar+O2	Ar+O2
Deposition rate [nm/min]	1.5 to 8nm/min	1.5 to 6nm/min
Uniformity over 8” [±%]1, 2	<±2%	<±2%
Reproducibility [±%]	<±3	<±3
Stress (compressive)2	<500MPa	<500MPa

Notes:

1. With 5mm edge exclusion
2. Stress and uniformity value are guaranteed for deposition rates up to 50% of maximum rate

Optofab 3000

Al2O3 Reactive Ion Beam Deposition in the Optofab3000

Process Specification

Deposition Gases: Ar, O2
Up to 200mm wafers
Summary performance data:

Chamber base pressurea	<3e-7 Torr
Load lock base pressureb	<1e-5 Torr

Al203 Uniformity - Click for larger image

Al2O3 Uniformity

Process specification

1. Al2O3 deposition with rotation and adjustable tilt.

Parameter/Process	Al2O3 dep	Al2O3dep
Target (size=200mm)	Al	Al2O3
Gas chemistry	Ar+O2	Ar+O2
Deposition rate [nm/min]	0.5 to 22nm/min	0.5 to 16nm/min
Refractive Index @ 632.8nm	1.6781	1.6709
Uniformity over 75mm thick annulus [±%]	< ± 0.5%	< ± 0.5%
Uniformity over 30mm thick annulus centred at 75mm substrate radius [±%]	< ± 0.3%	< ± 0.3%
Uniformity over 200mm (no shield)1,2	< ± 3%	< ± 3%
Reproducibility [±%]	< 3	< ± 3
Stress (compressive)2	< 500MPa	< 500MPa