P1.5 - Structuring of Spintronic Sensors by Ion Beam Milling with in situ Insulator Deposition
- AMA Conferences 2017
2017-05-30 - 2017-06-01
- Proceedings Sensor 2017
- P1 - Materials and Technology
- M. Nestler, S. Rumbke, E. Loos - scia Systems GmbH, Chemnitz (Germany), A. Böhnke, N. Dohmeier - Bielefeld University (Germany)
- 570 - 573
We demonstrate that high quality CoFeB/MgO/CoFeB magnetic tunnel junctions (MTJs) can be produced by combining magnetron sputtering, UV lithography, and ion beam milling (IBM). Particularly, we study the effect of different milling angles on the tunneling magnetoresistance (TMR). Furthermore, we investigate the quality of devices manufactured by depositing the insulator in situ subsequent to milling. Using a secondary ion mass spectrometer (SIMS), all layers can be detected while milling, enabling us to precisely define the mill stops. We found TMR values of up to 140% for a milling angle of 30° and 90% for a two angles milling process at 20° and 65°, proving that no critical sidewall redeposition of conductive material takes place.