Summary: Factors affecting surface roughness and coercivity of Ni80Fe20 thin films
V. Nga)
Information Storage Materials Laboratory, Department of Electrical and Computer Engineering, National
University of Singapore, 117576, Singapore
J. F. Hu
Information Storage Materials Laboratory, Department of Electrical and Computer Engineering, National
University of Singapore, 117576, Singapore and Data Storage Institute, 117608, Singapore
A. O. Adeyeye
Information Storage Materials Laboratory, Department of Electrical and Computer Engineering, National
University of Singapore, 117576, Singapore
J. P. Wang and T. C. Chong
Data Storage Institute, 117608, Singapore
This article reports the effects of dc sputter power, film thickness and rf substrate bias on surface
roughness and magnetic properties of Ni80Fe20 thin films sputtered on Si 100 substrates for their
application in magnetic tunneling junctions. The surface roughness of Ni80Fe20 thin films varied
from 0.197 nm to 0.376 nm when dc sputter power was changed from 50 to 250 W. The optimum
value was achieved with 200 W dc sputter power. Film thickness dependence study shows that the
surface roughness of Ni80Fe20 thin films changes from 0.164 nm to 0.264 nm, with a minimum at
film thickness of 8 nm. The small magnitude of change was attributed to a 20 W rf substrate bias
that was applied during the thickness studies. We varied the substrate rf bias from 0­20 W, with

Source: Adeyeye, Adekunle - Department of Electrical and Computer Engineering, National University of Singapore

Collections: Physics; Materials Science