Specific Process Knowledge/Lithography/ZEP520A

This is a standard positive resist from ZEON. The resist is very expensive; DTU Nanolab has thus stopped buying this resist. Use CSAR instead.

Contact lithography@nanolab.dtu.dk if you wish to use this resist.

Spin Curves

The thickness is measured on VASE Ellipsometer using a simple Cauchy model for a transparent polymer on a Si wafer with native oxide. The measurements are performed at one incidence angle (70 degrees) only. 9 points on each 4" wafer has been measured; the standard deviation thus represents the homogeinity of the film on the 4" wafers.

ZEON ZEP520A1:1 in anisole spinning on Spin Coater: Manual LabSpin A-5, TIGRE, 23-04-2014. Resist was mixed 13-01-2014, i.e. approximately 3 months old.
Spin Speed [rpm]	Acceleration [1/s2]	Thickness [nm]	St Dev
3000	4000	111.29	0.65
4000	4000	95.17	2.16
5000	4000	87.23	0.81

ZEON ZEP520A1:1 in anisole spinning on Spin Coater: Manual LabSpin A-5, TIGRE, 21-05-2014. Resist was mixed 15-05-2014, i.e. approximately 6 days old.
Spin Speed [rpm]	Acceleration [1/s2]	Thickness [nm]	St Dev
2000	4000	141.03	1.02
3000	4000	115.96	0.98
4000	4000	100.56	0.80
5000	4000	91.01	0.38
6000	4000	84.85	0.37

ZEON ZEP520A1:2 in anisole spinning on Spin Coater: Manual LabSpin A-5, TIGRE, 21-05-2014. Resist was mixed 15-05-2014, i.e. approximately 6 days old.
Spin Speed [rpm]	Acceleration [1/s2]	Thickness [nm]	St Dev
2000	4000	79.12	1.74
3000	4000	64.30	0.34
4000	4000	55.50	0.48
5000	4000	50.53	0.62
6000	4000	46.34	1.01