The Certain Researches Of Spintronics

Spintronics is a rising and attended research field presently.As well known,the basis of information technology is the charge of electron.Most of microelectronic device and processing unit in integrate circuit is based on the manipulation of charge in electronic circuit.And the magnetic property based on the spin of electron also possesses important role in passing economic life.For instance:information storage, identification and communication.The research purpose of spintronics is to combine this two properties of electron together.That means spin devices research and spin materials research.In this work,this two research objects all were studied and discussed.The main research contents just like follow:(1) The preparation of Co-doped ZnO diluted magnetic semiconductor in nano scale. Firstly,we prepared a series of porous anodic oxide aluminum template(diameter is from 10nm to 60nm) by DC constant voltage oxide technique in H2SO4 and C₂H₂O₄ electrolyte.Then Zn_99.35Co_0.65O nanowires were deposited in templates. The VSM testing proved the prepared Co-doped ZnO have distinct ferromagnetic property,and the EDS testing proved the proportion of element in Zn_xCo₍1-x_O is matched with the mol proportion of the reactants in solution.(2) The synthesis of Fe[001]/MgO[001]/Fe[001]magnetic tunnel junctions(MTJs) multilayer films.A series of Fe/MgO/Fe magnetic tunnel junctions were synthesized by low speed alternate sputtering,the testing results proved the different thickness of pre-sputtering layer has effect on the crystallographic properties of Fe/MgO/Fe tunnel junction.Meanwhile,the samples we fabricated were annealed in deferent temperature.The right annealing temperature can improve the crystallographic properties of tunnel junction.After XRD testing,we found the fabricated MTJs gained mutual[001]orientation of Fe and MgO after deposition of proper thickness pre-sputtering layer.At last,we found the optimal condition of the thickness of pre-sputtering layer and annealing temperature.The candidate of high spin-polarization electrodes was gained. (3) The characterization of long-distance transportation of spin current.The flat electrodes were deposited by alternate sputtering.The horizontal Kerr effect testing results demonstated the reversal of magnetization orientation.Then carbon nanotubes(CNTs) were connected between electrodes by dye electrophoresis method successfully.And the numbers of the connected CNT could be controlled also.In the MR testing,the 15%MR testing signal appeared when the external magnetic field reached 25 Oe.