CN101224904A - Method for preparing Fe doped ZnO room-temperature diluted magnetic semiconductor material - Google Patents

Abstract

The invention provides a method for preparing a Fe-doped ZnO room temperature diluted magnetic semiconductor material, which adopts a coprecipitation method and includes: A. prepare a mixed solution of Fe<3+> and Zn<2+> and a NaOH solution; B. mix the mixed solution of Fe<3+> and Zn<2+> and the NaOH solution to form a precipitate, then filter, separate and wash the precipitate; C. dry, pre-sinter, grind, tablet and sinter the precipitate to obtain the Fe-doped ZnO room temperature diluted magnetic semiconductor material. The invention provides a completely new method for preparing the Fe-doped ZnO room temperature diluted magnetic semiconductor material and the Fe-doped ZnO room temperature diluted magnetic semiconductor material prepared by the method has room temperature ferromagnetism.

Description

A kind of preparation method of Fe doped ZnO room-temperature diluted magnetic semiconductor material

Technical field

The invention belongs to novel semi-conductor spintronics material field, be specifically related to a kind of preparation method of transition metal doping zinc oxide room-temperature diluted magnetic semiconductor material.

Technical background

Eighties of last century has started the third technical revolution based on the semi-conductor industry of the utilization of elementary charge on human history, greatly promoted social progress.The another one degree of freedom of electronics, promptly spin has been left in the basket in the past fully.Nowadays, the travelling speed of traditional devices and storage density are more and more near its theoretical limit, and people just are being devoted to explore new information processing mechanism.Exploitation utilizes the spin electric device of the electric charge of electronics and the attribute that spins to begin to become the research focus in this field simultaneously.Dilute magnetic semiconductor is as a kind of novel semiconductor material, it will spin and two degree of freedom of electric charge combine in same matrix, possess excellent magnetic, magneto-optic and magnetic electricity performance simultaneously, can be used for developing the spinning electron and the nano electron device of a new generation, expand the development space of microelectronic, for the microminiaturization and the multifunction of microelectronic device provides solution, shown boundless application prospect at spintronics and optoelectronic areas, such as Spin Valve, spin diode, stable storer, logical device and high speed photoswitch or the like.

From application point of view, the dilute magnetic semiconductor material that the preparation Curie temperature is higher than room temperature is very important.More extensive based on the research of the dilute magnetic semiconductor of II-VI family and III-V compound semiconductor, as (Zn, Mn) Se and (Ga, Mn) As etc., but the Curie temperature of these materials is lower than 120K more, has limited their practical application.From Ueda etc. first at " Applied Physics Letters " (calendar year 2001 the 79th volume, P988-990) reported since the ZnO thin film doped room-temperature ferromagnetic of Co, in transient metal doped oxide semiconductor, found to be higher than the ferromagnetic semiconductor of room temperature successively, thereby caused that people are to oxide lanthanon magnetic semiconductor extensive studies interest.Wherein, dilute magnetic semiconductor material to the Fe doping ZnO but rarely has report in the world, and existing report result also is not quite similar, wherein only there is people such as Potzger in the single crystal samples of Fe doping ZnO, to observe room-temperature ferromagnetic [" AppliedPhysics Letters " (2006 the 88th volumes, and other report all fails to obtain room-temperature ferromagnetic in this material P052508)].

Summary of the invention

The present invention is directed to the method that does not prepare the Fe doped ZnO room-temperature diluted magnetic semiconductor material in the prior art, a kind of preparation method of Fe doped ZnO room-temperature diluted magnetic semiconductor material is provided, and this method can be prepared the Fe mixed ZnO semiconductor material that possesses room-temperature ferromagnetic.

A kind of preparation method of Fe doped ZnO room-temperature diluted magnetic semiconductor material may further comprise the steps:

A. with analytically pure Zn (NO ₃) ₂6H ₂O and Fe (NO ₃) ₃9H ₂After the O powder is fully mixed, adds deionized water it is dissolved fully, form Fe ³⁺And Zn ²⁺Mixed solution, wherein Fe and Zn mol ratio are 0: 100～2: 98; With NO ₃ ^-Ion mole number and OH ^-The ion mole number is 1: 1 an analytical pure NaOH powder, joins deionized water, is mixed with NaOH solution;

B. pour the NaOH solution for preparing into Fe ³⁺And Zn ²⁺Mixed solution in, constantly stir, dropping ammonia simultaneously, the pH value of control solution is 8≤pH value≤9, makes Fe ³⁺And Zn ²⁺Precipitation forms Fe (OH) fully ₃And Zn (OH) ₂Mixed precipitation; Throw out is filtered, separate, and use the deionized water repetitive scrubbing, remove the possible residual ion in throw out surface;

C. the throw out after will washing places 100 ℃ of-150 ℃ of baking ovens to dry, and with its grinding; Then carry out presintering in inert atmosphere, calcined temperature is 300 ℃-500 ℃, and the presintering time is 6-10 hour; With the powder process grinding again that obtains, compressing tablet, sintering under inert atmosphere, sintering temperature is 500 ℃-700 ℃, sintering time is 12-24 hour, promptly obtains the Fe doped ZnO room-temperature diluted magnetic semiconductor material.

The invention has the advantages that: this method technology is simple, easy handling, and good reproducibility is convenient to promote, and can be used for the preparation of the dilute magnetic semiconductor material of other transient metal doped ZnO; The Fe doping ZnO dilute magnetic semiconductor material of preparing has room-temperature ferromagnetic.

Description of drawings

Fig. 1 is sample S1, S2, the XRD figure spectrum of S3 and pure ZnO;

Fig. 2 is the XRD figure spectrum of agglomerating doping content x=3% sample under 600 ℃ of argon atmosphers;

Fig. 3 is agglomerating Zn under 600 ℃ of argon gas atmosphere _1-xFe _x(T=300K) magnetic hysteresis loop behavior under O (x=0.5%, 1%, 2%) the material room temperature.

Embodiment

Embodiment 1

Utilize the present invention to prepare 0.03mol room-temperature diluted magnetic semiconductor Zn _1-xFe _xO (x=0.005) material.The first step is with the analytically pure Zn (NO of electronic balance weighing ₃) ₂6H ₂O powder 8.92g and Fe (NO ₃) ₃9H ₂O powder 0.0606g, wherein Fe ³⁺Doping content be 0.1%, place beaker, add the 200ml deionized water it dissolved fully, form Fe ³⁺And Zn ²⁺Mixed solution; According to NO ₃ ^-Ion mole number (0.06042mol) and OH ^-The ion mole number is 1: 1, and the analytically pure NaOH powder of weighing 2.4168g adds the 100ml deionized water, is mixed with NaOH solution.In second step, pour the NaOH solution for preparing into Fe ³⁺And Zn ²⁺Mixed solution in, constantly stir, dropping ammonia simultaneously, the PH=8 of control solution makes Fe ³⁺And Zn ²⁺Precipitation forms Fe (OH) fully ₃And Zn (OH) ₂Mixed precipitation; Throw out is filtered, use deionized water wash 5 times, again throw out is separated.The 3rd step, with mixed sediment place baking oven under 100 ℃ with its oven dry, and with its grinding; Then presintering 8 hours in 400 ℃ of argon atmosphers; The powder again that will obtain at last ground 8 hours, compressing tablet then, and sintering is 12 hours in 600 ℃ of argon atmosphers, makes sample S1.Sample S1 is wurtzite structure completely, and its XRD figure spectrum as shown in Figure 1.

Embodiment 2

Utilize the present invention to prepare 0.01mol room-temperature diluted magnetic semiconductor Zn _1-xFe _xO (x=0.01) material.The first step is with the analytically pure Zn (NO of electronic balance weighing ₃) ₂6H ₂O powder 2.945g and Fe (NO ₃) ₃9H ₂O powder 0.0404g, wherein Fe ³⁺Doping content be 1%, place beaker, add the 200ml deionized water it dissolved fully, form Fe ³⁺And Zn ²⁺Mixed solution; According to NO ₃ ^-Ion mole number (0.101mol) and OH ^-The ion mole number is 1: 1, and the analytically pure NaOH powder of weighing 0.804g adds the 100ml deionized water, is mixed with NaOH solution.In second step, pour the NaOH solution for preparing into Fe ³⁺And Zn ²⁺Mixed solution in, constantly stir, dropping ammonia simultaneously, the PH=8 of control solution makes Fe ³⁺And Zn ²⁺Precipitation forms Fe (OH) fully ₃And Zn (OH) ₂Mixed precipitation; Throw out is filtered, use deionized water wash 5 times, again throw out is separated.The 3rd step, with mixed sediment place baking oven under 150 ℃ with its oven dry, and with its grinding; Then presintering 6 hours in 500 ℃ of argon atmosphers; The powder again that will obtain at last ground 8 hours, compressing tablet then, and sintering is 12 hours in 700 ℃ of argon atmosphers, makes sample S2.Sample S2 is wurtzite structure completely, and its XRD figure spectrum as shown in Figure 1.

Embodiment 3

Utilize the present invention to prepare 0.05mol room-temperature diluted magnetic semiconductor Zn _1-xFe _xO (x=0.02) material.The first step is with the analytically pure Zn (NO of electronic balance weighing ₃) ₂6H ₂O powder 14.5765g and Fe (NO ₃) ₃9H ₂O powder 0.404g, wherein Fe ³⁺Doping content be 2%, place beaker, add the 300ml deionized water it dissolved fully, form Fe ³⁺And Zn ²⁺Mixed solution; According to NO ₃ ^-Ion mole number (0.101mol) and OH ^-The ion mole number is 1: 1, and the analytically pure NaOH powder of weighing 4.04g adds the 100ml deionized water, is mixed with NaOH solution.In second step, pour the NaOH solution for preparing into Fe ³⁺And Zn ²⁺Mixed solution in, constantly stir, dropping ammonia simultaneously, the PH=9 of control solution makes Fe ³⁺And Zn ²⁺Precipitation forms Fe (OH) fully ₃And Zn (OH) ₂Mixed precipitation; Throw out is filtered, use deionized water wash 5 times, again throw out is separated.The 3rd step, with mixed sediment place baking oven under 120 ℃ with its oven dry, and with its grinding; Then presintering 10 hours in 300 ℃ of argon atmosphers; The powder again that will obtain at last ground 8 hours, compressing tablet then, and sintering is 18 hours in 500 ℃ of argon atmosphers, makes sample S3.Sample S3 is wurtzite structure completely, and its XRD figure spectrum as shown in Figure 1.

Adopt the Zn of above method preparation _1-xFe _xThe O material has room-temperature ferromagnetic, is a kind of dilute magnetic semiconductor with application prospect, can be used for preparing used target of diluted semi-conductor thin-film and spintronics field, opens the light or the like as spin light emitting diode, spin polarization(SP) solar cell, magneto-optic.Wherein adopt X-ray diffractometer (XRD) to the characterizing of sample structure, adopt comprehensive property tester (PPMS) that magnetic sample character is measured.

Structural analysis shows: doping content is lower than 2%, i.e. Zn _1-xFe _xThe concentration x scope of Fe is 0＜x≤0.02 o'clock in the O material, and (be S1, S2 S3) is phase structure to sample, and all diffraction peaks all can be according to pure ZnO wurtzite structure indexing, as shown in Figure 1; When being doped to 3%, in the XRD figure spectrum the second phase ZnFe appears ₂O ₄Assorted peak, as shown in Figure 2, these results show that the solid solubility of Fe ion in the ZnO lattice is very low, therefore when utilizing the present invention to prepare iron doping zinc-oxide room-temperature diluted magnetic semiconductor material, Fe doping content x scope is 0＜x≤0.02, and sintering temperature is unsuitable too high, and too high sintering temperature causes second to occur mutually easily.Magnetic measurement shows: all samples all show room-temperature ferromagnetic, and with the increase of doping component, ferromegnetism strengthens gradually, as shown in Figure 3.Adopt the present invention can make different Fe doping contents have a room-temperature ferromagnetic mix iron zinc oxide dilute magnetic semiconductor material.

Above-mentioned is that most preferred embodiment processing step of the present invention ground is described in detail; but obviously; the researchist in the technology of the present invention field can make the change of the unsubstantiality on form and the content and not depart from the scope that institute of the present invention essence is protected according to above-mentioned step; therefore, the present invention is not limited to above-mentioned concrete form and details.

Claims (2)

1. the preparation method of a Fe doped ZnO room-temperature diluted magnetic semiconductor material is characterized in that may further comprise the steps:

A. with analytically pure Zn (NO ₃) ₂6H ₂O and Fe (NO ₃) ₃9H ₂After the O powder is fully mixed, adds deionized water it is dissolved fully, form Fe ³⁺And Zn ²⁺Mixed solution, wherein Fe ³⁺Doping content be 0＜Fe ³⁺≤ 2%; With NO ₃ ^-Ion mole number and OH ^-The ion mole number is 1: 1 an analytical pure NaOH powder, joins deionized water, is mixed with NaOH solution;

B. pour the NaOH solution for preparing into Fe ³⁺And Zn ²⁺Mixed solution in, constantly stir, dropping ammonia simultaneously, the pH value of control solution is 8≤pH value≤9, makes Fe ³⁺And Zn ²⁺Precipitation forms Fe (OH) fully ₃And Zn (OH) ₂Mixed precipitation; Throw out is filtered, separate, and use the deionized water repetitive scrubbing, remove the possible residual ion in throw out surface;

C. the throw out after will washing places 100 ℃ of-150 ℃ of baking ovens to dry, and with its grinding; Then carry out presintering in inert atmosphere, calcined temperature is 300 ℃-500 ℃, and the presintering time is 6-10 hour; With the powder process grinding again that obtains, compressing tablet, sintering under inert atmosphere, sintering temperature is 500 ℃-700 ℃, sintering time is 12-24 hour, promptly obtains the Fe doped ZnO room-temperature diluted magnetic semiconductor material.

2. the preparation method of a kind of Fe doped ZnO room-temperature diluted magnetic semiconductor material according to claim 1 is characterized in that described inert atmosphere is an argon gas atmosphere.

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