Cambridge ALD: Difference between revisions

Cambridge ALD
Essentials
Full name	Savannah S100 (gen. 1)
Manufacturer	Cambridge NanoTech (Veeco)
Description	Atomic layer deposition system
Location	Cleanrooms 1 & 2
Responsibility
Primary	Martin
Secondary	Karolis

Revision as of 15:52, 19 February 2021

Deposited material	Precursor	ALD1	ALD2	Ref.
Hafnium oxide (HfOx, HfO₂)	TDMAH tetrakis(dimethylamino)hafnium [(CH₃)₂N]₄Hf	Yes	Yes	[1]
Aluminum oxide (AlOx, Al₂O₃)	TMA trimethylaluminum (CH₃)₃Al	Yes	Yes	[2]

Open valve on top of the nitrogen bottle.
Check nitrogen bottle pressure. Main bottle pressure should be at least 5 bar, line pressure 3 bar (AJA1) 1-2 bar (AJA2).
If line pressure is outside of range, carefully adjust the regulator valve with the flow set to 20 sccm.
Make sure the valves of all precursors inside the ALD machine are closed.
ALD1 only: run recipe Default_cleaning to pump out any residual gas in the gas lines.
With flow set to 0 the actual flow can be between 0-1 sccm.
Press the big round VENT or VENT REACTOR button.
Open the metal lid.
Put your sample inside, roughly in the center, away from the gas inlet and outlet.
Check whether the rubber O-ring is properly seated.
Close the metal lid. Check that the lid is aligned to sit directly on top of the reactor chamber.
Press the big round PUMP or PUMP REACTOR button.
Pressure with flow set to 0: ~5e-2 Torr or lower.
Place the metal cage on top of the tool.
Open relevant precursor valves.
Run your recipe.
Pressure with 20 sccm N₂ flow present: low e-1 Torr.

ALD1 pulse lengths: H₂O ~0.5 s, HfOx TDMAH 0.2 s, AlOx TMA 0.02 s.

ALD2 pulse lengths: H₂O ~0.02 s, HfOx TDMAH 0.2-0.5 s.
Close precursor valves.
Press the big round VENT or VENT REACTOR button.
Place the metal cage on the side of the tool.
Take out your sample. Check the rubber o-ring.
Press the big round PUMP or PUMP REACTOR button.
Close the nitrogen bottle valve on top of the bottle.
Run recipe Default_heater_set.

Recipe file location
ALD1: C:\Savannah\Users\Standard\

ALD2: C:\Cambridge Nanotech\Recipes\
Log file location
ALD1: C:\ALD data. Includes pressure data, screenshot at termination.

ALD2: C:\Cambridge Nanotech\Log\. Includes pressure and heater temperature data, screenshot at termination, software event logs.

Pressure reading obviously wrong (above 1e3 Torr or below 1e-4 Torr):
- Pressure gauge failure. Unplug the network cable from the small square pressure gauge beneath the chamber and plug it back in. The pressure reading should return to expected values.
No peak visible during precursor pulse:
- Precursor valves closed. Make sure the relevant precursor valves are open. Consult the labels on the inside of the door.
- Pulse time too short. Select the lowest plotting interval and check whether you can spot a small peak when the automatic valve opens. Increase pulse time as needed.
Cannot open lid upon venting:
- Chamber pressure still below atmosphere. Confirm pressure reading in software. If pressure is below 5e2 Torr, check whether the nitrogen bottle valve is open.
- Rubber O-ring can get stuck to the lid. Gently but firmly lift the lid. Reseat the O-ring if needed.

@@ Line 25: / Line 25: @@
 | Hafnium oxide (HfOx, HfO<sub>2</sub>)|| <div class="toccolours mw-collapsible mw-collapsed width:400px" style="width:300px"> TDMAH <div class="mw-collapsible-content">tetrakis(dimethylamino)hafnium <br/> [(CH<sub>3</sub>)<sub>2</sub>N]<sub>4</sub>Hf <br/> [[File:TDMAH.png|246px]]</div></div> || style="background-color: #c6e0b4" | Yes || style="background-color: #c6e0b4" | Yes || [https://doi.org/10.1016/j.tsf.2005.05.050]
 |-
-| Aluminum oxide (AlOx, Al<sub>2</sub>O<sub>3</sub>) || <div class="toccolours mw-collapsible mw-collapsed" style="width:300px> TMA <div class="mw-collapsible-content">trimethylaluminum <br/> (CH<sub>3</sub>)<sub>3</sub>Al <br/> [[File:TMA.png|290px]]</div></div> || style="background-color: #c6e0b4" | Yes || style="background-color: #ff9f9f" | No || [https://doi.org/10.1134/1.1626763]
+| Aluminum oxide (AlOx, Al<sub>2</sub>O<sub>3</sub>) || <div class="toccolours mw-collapsible mw-collapsed" style="width:300px> TMA <div class="mw-collapsible-content">trimethylaluminum <br/> (CH<sub>3</sub>)<sub>3</sub>Al <br/> [[File:TMA.png|290px]]</div></div> || style="background-color: #c6e0b4" | Yes || style="background-color: #ff9f9f" | Yes || [https://doi.org/10.1134/1.1626763]
 |}