Gerken, Anna: Realization of TMR devices in an industrial environment. 2010
Inhalt
- Eidesstattliche Erklärung
- 1 Introduction
- 2 Motivation
- 3 Theory
- 3.1 Tunneling Magnetoresistance
- 3.2 Half-metallic Ferromagnets - Heusler Alloys
- 3.2.1 Crystallographic Structure of Heusler Alloys
- 3.2.2 Half-Metallicity of Heusler Alloys
- 3.2.3 Slater-Pauling Behaviour of Heusler Alloys
- 3.2.4 Magnetic Tunneling Junctions with Heusler Electrodes
- 3.3 TMR with MgO Barriers
- 3.4 The System CoFeB-MgO-CoFeB
- 4 Sample Preparation
- 4.1 The Sputtering Tool
- 4.2 TMR Layer Stack
- 4.3 MgO Barrier Deposition
- 4.4 Annealing the Samples
- 4.5 Structuring the Samples
- 4.6 Quadrants-Wafer
- 4.7 TMR Tester
- 5 MgO Barrier Optimization
- 5.1 Seed-Layer Optimization
- 5.2 Ion Beam Standard Process
- 5.3 Ion Beam Assisted Process (IBAD)
- 5.4 Low Rate Process
- 5.5 Deposition with additional Oxygen
- 5.6 TMR as a Function of the Annealing Temperature
- 6 MgO Process Stability
- 6.1 Homogeneity over one Wafer
- 6.2 Reproducibility of TMR Standard Stacks
- 6.3 MgO Process Stability after Co2MnSi Deposition
- 7 Co2MnSi Thin Films
- 7.1 X-Ray Diffraction Analysis
- 7.1.1 Seed Layer Optimization
- 7.1.2 Co2MnSi deposited by IBAD
- 7.1.3 Co2MnSi Thin Films on MgO Substrates
- 7.1.4 Co2MnSi Thin Films in (110) Orientation
- 7.2 X-Ray Reflectometry
- 7.3 Magnetic Characterization
- 7.4 Transport Measurements
- 8 Summary and Outlook
- A Mask Drawing
- B Generic Process Flow
- C EDX-Analysis of the Co2MnSi Target
- D List of X-Ray Diffraction Peak Positions
- E Publications & Talks
- Danksagung