Specific Process Knowledge/Thin film deposition/Deposition of Niobium

Deposition of Niobium

Niobium can be deposited by e-beam evaporation or sputtering. In the chart below you can compare the deposition equipment.

	E-beam evaporation (Temescal)	Sputter deposition (Lesker)	Sputter deposition (Sputter-system Metal-Oxide (PC1) and Sputter-system Metal-Nitride (PC3))
General description	E-beam deposition of Nb (line-of-sight deposition)	Sputter deposition of Nb (not line-of-sight deposition)	Sputter deposition of Nb (not line-of-sight deposition)
Pre-clean	Ar ion bombardment	none	RF Ar clean
Layer thickness	10Å to 200 nm*	10Å to 600 nm**	ask staff, probably similar to old Lesker sputter system
Deposition rate	0.5Å/s to 5Å/s	~1Å/s	? Probably similar to old Lesker sputter system
Batch size	Up to 4x6" wafers Up to 3x8" wafers (ask for holder) smaller pieces	smaller pieces Up to 1x6" wafers	Up to 10x4" or 6" wafers Many smaller pieces
Allowed materials	Silicon Silicon oxide Silicon (oxy)nitride Photoresist PMMA Mylar Metals See also the cross-contamination sheet	Silicon Silicon oxide Silicon (oxy)nitride Photoresist PMMA Mylar SU-8 Metals	Almost any that do not outgas.
Comment	Substrates get heated during the deposition. For 100 nm Nb at 2 Å/s, the substrate reached about 105 °C.

* To deposit layers thicker than 200 nm permission is required to ensure that there is enough metal (contact metal@nanolab.dtu.dk)

** To deposit layers thicker than 600 nm permission is required to ensure that there is enough metal (contact metal@nanolab.dtu.dk)