Specific Process Knowledge/Thin film deposition/Deposition of Tungsten
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Tungsten deposition
Tungsten (W) can be deposited by e-beam evaporation and sputtering. However, in case of evaporation the precess generates a lot of heat (despite water cooling), and this means the pressure rises as the chamber is baking out. It is therefore not easy to deposit films much thicker than 50-60 nm. In the Temescal we stopped the deposition every 20 nm to let the pressure drop. Also, the rate needs to be low, to avoid overheating. Talk to staff when you want to deposit W (write to thinfilm@nanolab.dtu.dk). Sputtering can be used without any sufficient issues. In the chart below you can compare the deposition equipment.
Evaporation of W
Sputtering of W
- Sputtering of Tungsten in the Sputter Coater 3
- DC Sputtering of Tungsten in the Sputter-System (Lesker)
- DC Sputtering of Tungsten in the Sputter-system Metal-Nitride (PC3)
- HiPIMS Sputtering of Tungsten in the Sputter-system Metal-Nitride (PC3)
E-beam evaporation (Temescal) | Sputter-system (Lesker) | Sputter deposition ((Sputter-system Metal-Oxide (PC1) and Sputter-system Metal-Nitride (PC3)) ) | Sputter coater (Sputter coater 03) | |
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General description | E-beam evaporation of W | DC Sputtering of W | DC and HiPIMS Sputtering of W | DC Sputtering of W |
Pre-clean | Ar ion beam | None | RF bias on a substrate | None |
Layer thickness | 10Å to 20nm* | 10Å to 600nm | 10Å to 600nm | 10Å to 250nm |
Deposition rate | 0.5 Å/s to 1 Å/s | about 1 Å/s | about 1 Å/s | configuration dependent |
Batch size |
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Allowed materials |
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Comments | Substrate gets hot during deposition
(for a 60 nm film it rose above 123 C) Wait for low base pressure before start (3-5 10-7 Torr) |
Deposition rate is 0.107 nm/s for 150W and 3mTorr (Src3, DC) | Deposition rate is 0.124 nm/s for 140W and 3mTorr (PC3, Src3 DC),
(0.04 nm/s using HiPIMS - PC3, Src3) |
Note! Bad uniformity.
Deposition rate is 0.03 nm/s using big glass chamber. Deposition rate is 0.2-0.9 nm/s (current dependent) using small glass chamber. |
* For thicknesses above 20 nm talk to staff (write to thinfilm@nanolab.dtu.dk), as the heat and subsequent pressure rise means the deposition needs to be carried out in steps.