Ultra-high thermal stability of perpendicular magnetic anisotropy in the W buffered CoFeB/MgO stacks with Zr dusting layers
3
Citation
45
Reference
10
Related Paper
Citation Trend
Abstract:
Practical device applications of magnetic multilayers with perpendicular magnetic anisotropy (PMA) usually need to match the mature complementary metal-oxide-semiconductor (CMOS) integrated techniques, which require high temperature annealing during the back-end-of-line process. Here, we report the realization of PMA in the W buffered CoFeB/MgO stack by inserting a thin Zr dusting layer between CoFeB and MgO layers. An ultra-high thermal stability of PMA in the W/CoFeB/Zr/MgO stack is observed, which is robust upon annealing at 600 °C. The establishment of PMA in W/CoFeB/Zr/MgO is due to the formation of an interface layer between CoFeB and MgO doped with oxidized Zr. After annealing at 540 °C, the magnetic interfacial anisotropy density reaches 3.08 erg/cm2, which is much higher than those in previous reports. The results suggest that the W/CoFeB/Zr/MgO stack with extra high annealing stability is a potential candidate to achieving the practical application of spin-logic device that is compatible with the mature CMOS integrated techniques.Keywords:
Thermal Stability
The objective of this study was to fabricate a self-humidifying fuel cell stack humidified with water recovered at the cathodes, composed of 10 cells with 104 cm2 cell areas, measure and simulate the performance of the stack. The model for the simulation is a three-dimensional model of the heat and mass transfer of water and gaseous reactants in fuel cell components with water cooling. The results of the stack experiments showed a maximum power of 250 W at the current density of 0.5 A/ cm2. The simulation model showed good agreement with the actual performance of the stack. A self-humidifying stack with a vapor permeating membrane showed a performance comparable to conventional stacks and it is very effective in simplifying stack systems. The numerical analysis showed that the stack performance is affected by the anode and cathode gas flows, co-flow is superior to cross-flow and that one cooing cell is necessary for two or three generating cells to maintain a fuel cell temperature below 100°C.
Cite
Citations (0)
In this paper, a self-breathing 10-cell microdirect methanol fuel cell (μ-DMFC) stack with double-planar structure is designed, fabricated, and tested. With the help of microstamping technology, the current collectors are microfabricated on the 300 μm-thick stainless steel plate. First, the steady-state performance of the stack is tested. Fed with 2 mL min−1 of 1 M methanol solution, the maximum power output of the stack can reach 141.0 mW at room temperature with a density of 22.03 mW cm−2. The dynamic performance of this stack is also investigated under several loading modes in consideration of practical conditions. The stack performance represents good responding and reproducible ability in most cases, but deteriorates to varying degrees with the increment of loading cycles. Finally, the μ-DMFC stack proves its good performance in powering two electronic devices five times in 120 days successfully while performance deterioration behavior is also detected.
Power density
Cite
Citations (5)
Phosphoric acid
Cite
Citations (24)
Cite
Citations (30)
In this study, we investigated a stack of direct dimethyl ether fuel cell (DDFC). A small passive DDFC stack had been developed, and a good uniformity could be observed from all single cells. The open-circuit voltage (OCV) of the stack was around 4 V, and its maximum power was 300 mW. No matter which means was adopted, only the values of current and voltage can be changed. The total output power of the stack remains the same. Therefore, based on the different requirements of electrical appliances on discharge, different ways of electric connection can be adopted for the stack.
Dimethyl ether
Open-circuit voltage
Cite
Citations (1)
The first compound capable of forming a bundled-stack discotic columnar liquid crystalline (BSDCLC) phase was designed and synthesized. The unique perylene anhydride inter-stack interaction was found to be the key to the formation of the BSDCLC structure and inter-stack electronic coupling (ISEC).
Discotic liquid crystal
Columnar phase
Cite
Citations (10)
Constant current
Cite
Citations (5)
A lightweight 200W direct methanol fuel cell (DMFC) stack is designed and fabricated to power a small scale Unmanned Aerial Vehicle (UAV). The DMFC stack consists of 33-cells in which membrane-electrode assemblies (MEAs) having an active area of 88 $cm^2$ are sandwiched with lightweight composite bipolar plates. The total stack weight is around 3.485 kg and stack performance is tested under various methanol feed concentrations. The DMFC stack delivers a maximum power of 248 W at 13.2 V and $71.3^{\circ}C$ under methanol feed concentration of 1.2 M. In addition, the voltage of individual cell in the 33-cell stack is measured at various current levels to ensure the stability of DMFC stack operations. The cell voltage distribution data exhibit the maximum cell voltage deviation of 28 mV at 15 A and hence the uniformity of cell voltages is acceptable. These results clearly demonstrate that DMFC technology becomes a potential candidate for small-scale UAV applications.
Maximum power principle
Cell voltage
Cite
Citations (2)
The temperature of the proton exchange membrane fuel cell(PEMFC)stack is a key factor to influence the performance of the cell.It is necessary to build a model of PEMFC stack in order to control the temperature exactly.A approach using the method of BP neural networks to model the PEMFC stack was put forward and used to fit the experimental dates,the results was satisfying.
Cite
Citations (0)