Magnetoresistance Element ZnO Interface Layer Heat Treatment Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in developing a thin film magnetic head is to maintain a high magnetoresistance ratio while minimizing magnetic layer characteristic degradation due to heat treatment processes, such as annealing, which often occurs in the manufacturing of high-sensitivity and high-output recording heads.
Innovation Solution
Incorporating a non-magnetic intermediate layer made of ZnO sandwiched between two magnetic layers, with intermediate interface layers containing Ag and Zn or Au and Zn, which prevent atom diffusion and maintain spin polarizability, thereby reducing the adverse effects of heat treatment on the magnetic layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a non-magnetic intermediate layer made of ZnO is used to achieve a large magnetoresistance ratio, then the MR ratio is improved, but the magnetic layer characteristics are degraded due to Zn and O atom diffusion during heat treatment
Solution Approach 1:
An intermediate interface layer containing Ag and Zn or Au and Zn is introduced between the magnetic layer and the ZnO non-magnetic intermediate layer. This intermediate layer acts as a mediator that prevents Zn and O atoms from diffusing into the magnetic layer during heat treatment, while still allowing the system to achieve a large magnetoresistance ratio through the ZnO layer.
Solution Approach 2:
The interface structure uses a composite material approach by combining Ag-Zn or Au-Zn alloy in the intermediate interface layer. This composite structure provides both the diffusion barrier function needed to protect the magnetic layer and maintains the electrical properties necessary for achieving high magnetoresistance ratio.
2Reliability
If an intermediate interface layer made of Zn is used to reduce magnetic characteristic degradation, then the spin polarizability is maintained, but Zn atoms diffuse into the magnetic layer during heat treatment causing MR ratio decrease
Solution Approach 1:
The Ag-Zn or Au-Zn intermediate interface layer serves as an improved intermediary compared to pure Zn. It maintains the spin polarizability function while the Ag or Au component provides enhanced resistance to Zn atom diffusion into the magnetic layer during heat treatment.
Solution Approach 2:
The composition of the intermediate interface layer is changed from pure Zn to Ag-Zn or Au-Zn alloy. This parameter change in material composition provides both the spin polarizability maintenance function and the diffusion barrier function simultaneously.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration achieves a high magnetoresistance ratio while minimizing magnetic layer degradation during heat treatment, ensuring the thin film magnetic head maintains sensitivity and output performance.
Implementation Method 1
it is important that oxidation of a magnetic layer is prevented
Implementation Method 2
Zn and O atoms are diffused from a non-magnetic intermediate layer to a magnetic layer even though through an intermediate interface layer
Implementation Method 3
when a giant magnetoresistance (GMR) effect is utilized by using a semiconductor material as a non-magnetic intermediate layer sandwiched by magnetic layers
Implementation Method 4
the magnetization direction of the ferromagnetic layer is fixed in one direction by means of exchange coupling with the antiferromagnetic layer
Data Source
AI summary
A thin film magnetic head includes a magnetoresistive effect (MR) laminated body that has the following structure: first and second magnetic layers in which the magnetization direction of at least one of the magnetic layers changes according to an external magnetic field; the first magnetic layer is provided at a lower side of a laminated direction; the second magnetic layer is provided at an upper side of the laminated direction; a non-magnetic intermediate layer made of ZnO sandwiched between the first and the second magnetic layers; a first intermediate interface layer is provided at the interface between the first magnetic layer and the non-magnetic intermediate layer; and a second intermediate interface layer is provided at the interface between the non-magnetic intermediate layer and the second magnetic layer. At least the first intermediate interface layer contains Ag and Zn, or Au and Zn.