Realization of TMR devices in an industrial environment

Magnetoresistive sensors are widely used in sensor applications for magnetic field measurements. Currently these sensors mostly use the Anisotropic Magnetoresistive Effect (AMR) or the Giant Magnetoresistive Effect (GMR). Due to their unique properties sensors based on the TMR effect could be advantageous: They offer a higher MR-ratio, smaller lateral dimensions and a higher resistance which reduces the power consumption. The work presented here is a purely industrial work, i.e. all experiments were performed directly on production tools at Sensitec GmbH in Mainz. In contrast to university research the focus was shifted to reproducibility and wafer uniformity instead of creating single perfect samples. In this thesis a TMR layer stack consisting of sputtered CoFeB electrodes, one of them being exchange-coupled with IrMn, and an ion beam deposited MgO barrier is presented. This system was studied by many research groups and is now transferred to an industrial environment. In contrast to most publications, the MgO barrier is being prepared by ion beam deposition, a novel preparation method for TMR stacks. Additionally Co2MnSi films for the use as potential electrodes were prepared by ion beam deposition and characterized structurally and magnetically.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Universität Bielefeld

Year

2010

Author dc:creator

• Gerken, Anna

Repository record source_url

https://pub.uni-bielefeld.de/record/2306435

OAI identifier oai:identifier

oai:pub.uni-bielefeld.de:2306435