CN107056271B - GaFeO3Ceramic target material and preparation method of nano film - Google Patents

Abstract

The invention discloses a preparation method of a GaFeO ₃ ceramic target material and a nano film. SPS spark plasma hot-pressing sintering GaFeO ₃ , sintering at high temperature and high pressure, cooling to room temperature, nanocrystals grow into dense targets under high pressure, and the sintered blank ceramic target is placed in a tube furnace for the next process ; High temperature sintering in a tube furnace, oxygen atmosphere, oxygen is introduced to prevent defects caused by oxygen deficiency during the sintering process, and then affect the density; the obtained nanocrystalline ceramic target is placed in the PLD sample holder, vacuumed, and the substrate Heating, feeding O ₂ during deposition to maintain a certain pressure, preventing the formation of oxygen vacancies and related defects, and obtaining a nano-magnetic thin film GaFeO ₃ . The target material prepared by the invention has the advantages of no impurity phase, flat and dense, and high density, and the high-quality film deposited by PLD on the obtained target material has the characteristics of small coercive field and strong saturation magnetization.

Description

A kind of GaFeO3 ceramic target material and preparation method of nano film

technical field

The invention relates to a preparation method of a GaFeO ₃ ceramic target material and a nanometer film, and belongs to the technical field of the preparation of a ceramic target material and a nanometer magnetic film.

Background technique

Nano-magnetic films have the advantages of both nano and magnetic films, and have unique properties in the fields of light, magnetism, and electricity, especially at low temperatures. High-density magnetic recording and magnetic recording materials; flexible, high-sensitivity, low-energy-consumption power equipment and electronic devices; broadband absorbing materials have a wide and important role in the development of today's society, and have become a current research focus. The nano-magnetic films prepared by the simple sol-gel method by spray deposition technology show relatively weak performance due to internal defects and pollution, which cannot meet the needs of precise experiments and industrial production. In recent years, the rapidly developed and relatively mature pulsed laser deposition (PLD) and molecular beam epitaxy (MBE) techniques can assemble high-quality nanomagnetic films at the atomic scale. The first step for obtaining a high-quality nano-magnetic film is to obtain a flat, dense, and single-component magnetic target. _GaFeO3 is a multiferroic material that exhibits both spontaneous electric polarization and magnetization at low temperature, especially strong ferromagnetism.

Existing _GaFeO3 usually has two different preparation methods: (1) using sol-gel method; (2) using traditional solid-phase sintering.

The first process is easy to produce impurity phases, especially for the preparation of pure GaFeO ₃ , which has good phase formation, the resulting film has poor density, and is easy to break during the sintering process; the second process can also effectively eliminate impurity phases, but because of the rapid temperature rise During the sintering process, the target shrinks violently, and is easily deformed and fractured during sintering. This effect is especially obvious when preparing a target with a larger area.

SUMMARY OF THE INVENTION

In view of the above problems, the present invention provides a preparation method of a nanocrystalline GaFeO ₃ low-temperature strong magnetic ceramic target and a thin film. The prepared target has the advantages of no impurity phase, flat and dense, and high density. High-quality films have the characteristics of small coercive field and high saturation magnetization.

The technical scheme adopted by the present invention to solve its technical problems is:

A method for preparing a GaFeO ₃ ceramic target material and a nano-film, comprising the following steps:

1) Mixing ball mill, mix the analytically pure Fe ₂ O ₃ and Ga ₂ O ₃ in a molar ratio of 1:1, and grind for 20-40 minutes. The mixed powder is uniform without color and layered, and the mixed powder is placed in a stainless steel volume. Add anhydrous ethanol into the ball mill jar, put in stainless steel grinding beads, seal the ball mill tube and use a ball mill at room temperature for ball milling at room temperature, first at a slow speed of 80 r/min for 4-6 hours, and at a fast speed of 300 r/min for 10-14 hours , use a sieve with an aperture of 50-100 mesh to separate the balls, and dry them at 60-80°C for 2-4 hours;

2) Sintering, put the dried powder into the graphite mold, and sintering with discharge plasma rapidly. The pressure during the sintering process is 28-32Mpa, the heating rate is 70-90°C/min, and the temperature is 800-1000°C for 4-6 minutes. , and then quickly cool to room temperature within 10 minutes, and push the sintered material out of the mold;

3) The metastable phase GaFeO ₃ rough ceramic target obtained after pushing out the mold is annealed at high temperature in a tube furnace, sintered at 1100-1300 ℃ for 6-8 hours, and sintered in an oxygen atmosphere to form high-density nanocrystals with a stable structure GaFeO ₃ ceramic target, thus obtaining a nanocrystalline low-temperature strong ferromagnetic GaFeO ₃ ceramic target;

4) Put the GaFeO ₃ ceramic target obtained in step 3 on the PLD target tray, use single crystal Si (111) as the substrate, evacuate to 3 × 10 ^-5 Pa, and heat the substrate to 700 ° C for preparation. For deposition, fine-tune the leak valve to introduce O ₂ to keep the vacuum at 4×10 ^-2 Pa, open the target autobiography control software to control the autobiography rate of the target at 2-4°/s, turn on the KrF excimer laser, Adjust the laser energy to 300-400mJ, frequency 2-4Hz, turn the substrate rotary handle so that the deposition surface faces the sputtering plume, and keep the deposition in a relatively stable state for 6-8 hours;

5) After the deposition is completed, the substrate is cooled slowly, and the cooling rate is ≤3°C/hour to prevent the nano-magnetic GaFeO ₃ from breaking due to quenching shrinkage. When it cools to room temperature, turn off the vacuum equipment and cooling equipment, and open the flange to obtain the nano-magnetic GaFeO ₃ thin films.

In step (1), the molar ratio of Fe ₂ O ₃ , Ga ₂ O ₃ and absolute ethanol is 1:1:3-5, and the mass ratio of the total mass of Fe ₂ O ₃ and Ga ₂ O ₃ to the stainless steel grinding beads is 1 : 3-5, the diameter distribution of stainless steel grinding beads is: the number of stainless steel grinding beads with diameter > 1mm is 20-30%, and the number of stainless steel grinding beads with diameter ≤ 1mm is 70-80%.

In the step (4), the GaFeO ₃ ceramic target placed in the PLD target tray is selected to have a diameter of less than 28 mm, and the use area of single crystal Si (111) is 10 mm×10 mm.

The invention proposes a new method for preparing a nanocrystalline GaFeO ₃ ceramic target material assembled by high pressure of nanocrystalline grains. The obtained target material has strong ferromagnetism at low temperature. , the coercive field is abnormally small, and the coercive field has almost no increase or decrease at low temperature, but the saturation magnetization is sharply enhanced, and there is strong ferromagnetism at low temperature. This low-temperature strong magnetic and small coercive field can be used as a piezomagnetic phase in the magnetoelectric coupling weak magnetic detection technology, and has the characteristics of high sensitivity and high resolution.

The invention uses SPS discharge plasma hot pressing sintering combined with high temperature tube furnace to prepare nanometer low temperature strong ferromagnetic GaFeO ₃ ceramic target material.

The preparation of nanocrystalline low temperature strong ferromagnetic GaFeO ₃ ceramic target and film is carried out in three steps:

SPS spark plasma hot-pressing sintering GaFeO ₃ , sintering under high temperature and high pressure, cooling to room temperature, and rapidly increasing the temperature during the sintering process, which inhibits the growth of crystal grains and forms nanocrystals. Many fine nanocrystals grow into dense under high pressure. For the target material, the mold removal and mass production factors are considered in the actual process, and the rough ceramic target formed after sintering is put into the tube furnace for the next process;

High temperature sintering in the tube furnace, oxygen atmosphere, oxygen is introduced to prevent defects caused by oxygen deficiency during the sintering process, thereby affecting the density.

The obtained nanocrystalline ceramic target is placed in the PLD sample holder, vacuumed, the substrate is heated, the laser energy is 300-400mJ, the frequency is 2-4Hz, and O ₂ is introduced to maintain a certain pressure during deposition to prevent the formation of oxygen vacancies. , to obtain the nano-magnetic thin film GaFeO ₃ .

The SPS rapid sintering furnace used produced nanocrystalline metastable phase GaFeO ₃ rough ceramic targets. Due to the pressure sintering process of SPS, the growth of grains was inhibited, forming nanocrystals, which self-assembled under high pressure. For the nanocrystalline target, the oxygen vacancies and defects in the crystal grains are repaired by annealing in an oxygen atmosphere in a tube furnace, so the nanometer target is obtained. Nanomagnetic films are prepared by PLD deposition technology. Due to the dimensional effect of nanofilms, the magnetic properties of nanomagnetic films are very different from those of bulk targets. The most direct manifestation is in the coercive field, the coercion of bulk targets The coercive field increases rapidly with the decrease of temperature and can reach 1T at 10K, while the coercive field of the film hardly changes with the decrease of temperature and remains at 20Oe.

The beneficial effects of the present invention are reflected in: the single-phase metastable structure GaFeO ₃ nanocrystalline blank ceramic target is prepared by SPS discharge plasma hot pressing, and the dense nanocrystalline low temperature strong magnetic GaFeO ₃ target is formed after high temperature thermal annealing in a tube furnace The obtained target is deposited by PLD to obtain a nano-magnetic film, which has a unique dimensional effect. The coercive field temperature of the film is fixed at 20Oe and does not change with the decrease of temperature, and the saturation magnetic moment increases sharply with the decrease of temperature. The obtained nano-magnetic thin film can be used in magnetoelectric coupling weak magnetic detection of piezoelectric phase in micro-devices, which has great practical value and scientific research significance.

The prepared target has the advantages of no impurity phase and high flatness and density, and the size of the prepared target can be made according to requirements, and can be used for various sputtering coatings. The dimensional effect of the thin films obtained by PLD is outstanding, and has great prospects for industrial application and scientific research.

Description of drawings

The present invention will be further described below with reference to the accompanying drawings and embodiments.

Fig. 1 is the XRD diffractogram of the pure phase GaFeO ₃ ceramic target prepared by the present invention.

FIG. 2 is a low-temperature magnetic diagram of the pure-phase GaFeO ₃ ceramic target prepared by the present invention.

FIG. 3 is a low-temperature magnetic diagram of the PLD-deposited nano-magnetic film of the ceramic target prepared by the present invention.

Detailed ways

The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are all simplified schematic diagrams, and only illustrate the basic structure of the present invention in a schematic manner, so they only show the structures related to the present invention. As shown in Figures 1, 2 and 3.

A preparation method of a GaFeO ₃ ceramic target material and a nano film, which is prepared by a spark plasma hot pressing sintering method, comprising the following steps:

1) Mixing ball mill, mix the analytically pure Fe ₂ O ₃ and Ga ₂ O ₃ in a molar ratio of 1:1, and grind for 20-40 minutes. The mixed powder is uniform without color and layered, and the mixed powder is placed in a stainless steel volume. Add anhydrous ethanol into the ball mill jar, put in stainless steel grinding beads, seal the ball mill tube and use a ball mill at room temperature for ball milling at room temperature, first at a slow speed of 80 r/min for 4-6 hours, and at a fast speed of 300 r/min for 10-14 hours , use a sieve with an aperture of 50-100 mesh to separate the balls, and dry them at 60-80°C for 2-4 hours;

2) Sintering, put the dried powder into the graphite mold, and sintering with discharge plasma rapidly. The pressure during the sintering process is 28-32Mpa, the heating rate is 70-90°C/min, and the temperature is 800-1000°C for 4-6 minutes. , and then quickly cool to room temperature within 10 minutes, and push the sintered material out of the mold;

3) The metastable phase GaFeO ₃ rough ceramic target obtained after pushing out the mold is annealed at high temperature in a tube furnace, sintered at 1100-1300 ℃ for 6-8 hours, and sintered in an oxygen atmosphere to form high-density nanocrystals with a stable structure GaFeO ₃ ceramic target, thus obtaining a nanocrystalline low-temperature strong ferromagnetic GaFeO ₃ ceramic target;

4) Put the GaFeO ₃ ceramic target obtained in step 3 on the PLD target tray, use single crystal Si (111) as the substrate, evacuate to 3 × 10 ^-5 Pa, and heat the substrate to 700 ° C for preparation. For deposition, fine-tune the leak valve to introduce O ₂ to keep the vacuum at 4×10 ^-2 Pa, open the target autobiography control software to control the autobiography rate of the target at 2-4°/s, turn on the KrF excimer laser, Adjust the laser energy to 300-400mJ, frequency 2-4Hz, turn the substrate rotary handle so that the deposition surface faces the sputtering plume, and keep the deposition in a relatively stable state for 6-8 hours;

5) After the deposition is completed, the substrate is slowly cooled down, and the cooling rate is ≤3°C/h to prevent the nano-magnetic GaFeO ₃ from breaking due to quenching shrinkage. When it cools to room temperature, turn off the vacuum equipment and cooling equipment, and open the flange to obtain the nano-magnetism. GaFeO ₃ thin films.

In step (1), the molar ratio of Fe ₂ O ₃ , Ga ₂ O ₃ and absolute ethanol is 1:1:3-5, and the mass ratio of the total mass of Fe ₂ O ₃ and Ga ₂ O ₃ to the stainless steel grinding beads is 1 : 3-5, the diameter distribution of stainless steel grinding beads is: the number of stainless steel grinding beads with diameter > 1mm is 20-30%, and the number of stainless steel grinding beads with diameter ≤ 1mm is 70-80%.

In the step (4), the GaFeO ₃ ceramic target placed in the PLD target tray is selected to have a diameter of less than 28 mm, and the use area of single crystal Si (111) is 10 mm×10 mm.

Example 1

Preparation of Single-Phase Nanometer Low-Temperature Strong Ferromagnetic _GaFeO3 Ceramic Target and Nanomagnetic Thin Film

Using the following raw materials (all of which are analytically pure, with a purity of more than 99.9%), the nano-assembled GaFeO ₃ ceramic target was prepared by using SPS hot pressing sintering furnace combined with high temperature tube furnace; PLD deposition technology was used for the prepared target. Deposition is carried out to obtain a nano-magnetic thin film.

The following are specific methods for preparing single-phase nanocrystalline GaFeO ₃ low-temperature ferromagnetic ceramic targets and nano-magnetic films

1.1) Mix the analytically pure Fe ₂ O ₃ and Ga ₂ O ₃ into raw materials according to the general formula GaFeO ₃ and grind them in an agate mortar for 30 minutes. The powder to be mixed is uniform and colorless.

1.2) Put the mixed powder into a stainless steel ball mill with a volume of 2L, add 80ml of pentahydrate ethanol, and put in an appropriate amount of stainless steel balls with different diameters. The slow speed is 80 rpm for 5 hours, and the fast speed is 300 rpm for 12 hours.

1.3) Use an iron sieve with a diameter of 80 meshes to separate the balls, and at the same time, if the fine powder obtained at the same time does not pass completely at one time, the filter residue can be reciprocated several times until all the sieve holes pass through, and the fine mixed powder after filtration is dried at 70 ℃. Dry for 3 hours.

1.4) Put the solution obtained above into an oven, set a temperature of 80°C and dry the solution for 24 hours.

1.5) Put the obtained dried powder into a mortar and grind it for 20 to 30 minutes and put it into a graphite mold with a diameter of 28 mm, and use SPS to quickly hot press and sinter it; 5 minutes, then 10 minutes to cool quickly to room temperature.

1.6) The GaFeO ₃ rough ceramic target in the metastable phase obtained after exiting the mold was annealed at high temperature in a tube furnace, sintered at 1200 ° C for 7 hours, and the beam flow was 0.3 ml/min in an oxygen atmosphere; sintered into a high temperature stable structure Density nanocrystalline GaFeO ₃ ceramic target. So far, a nanocrystalline low-temperature strong ferromagnetic GaFeO ₃ ceramic target has been obtained.

1.7) Put the GaFeO ₃ ceramic target with a diameter of slightly less than 28 mm obtained in step 6 on the target tray of the PLD deposition chamber, use single crystal Si (111) with an area of 10 mm × 10 mm as the substrate, and evacuate to 3 × 10 ^{- 5} , while heating the substrate to 700°C for deposition.

1.8) A small amount of O ₂ was introduced into the fine-tuning leak valve to keep the vacuum at a dynamic balance of 4×10 ^-2 Pa. Open the target autobiography control software to control the target autobiography rate at 3°/s; open the KrF excimer laser , adjust the laser energy to 350mJ, the frequency is 3Hz, turn the substrate rotary handle so that the deposition surface is facing the sputtering plume, and keep the deposition in a relatively stable state for 7 hours. After the deposition is completed, the substrate is slowly cooled to room temperature, the vacuum system and cooling system are closed, and the nanomagnetic film obtained by opening the flange can be used for further research or testing.

As shown in Figure 1, the X-ray diffraction pattern shows that the prepared ceramic target is a single-phase composition of GaFeO ₃ with a perovskite structure with good crystallinity. The XRD diffraction patterns of the PLD-deposited films are very close to those of the target, so they are not given here.

Example 2

A preparation method of a GaFeO ₃ ceramic target material and a nano film, which is prepared by a spark plasma hot pressing sintering method, comprising the following steps:

1) Mixing ball mill, mix analytically pure Fe ₂ O ₃ and Ga ₂ O ₃ in a molar ratio of 1:1, and grind for 30 minutes. The powder to be mixed is uniform without color and layering, and the mixed powder is placed in a stainless steel ball mill. Add anhydrous ethanol, put in stainless steel grinding beads, seal the ball mill tube and use a ball mill at room temperature for ball milling at room temperature, first at a slow speed of 80 rpm for 5 hours, and at a fast speed of 300 rpm for 12 hours, using a 75-mesh aperture. The sieve separates the ball material, and it is dried at 72°C for 3 hours;

2) Sintering, put the dried powder into a graphite mold, and sinter it by rapid hot pressing with discharge plasma. The pressure during the sintering process is 29Mpa, the heating rate is 85°C/min, and the temperature reaches 950°C for 4.5 minutes, and then rapidly cooled to 10 minutes. At room temperature, push the sintered material out of the mold;

3) The metastable phase GaFeO ₃ rough ceramic target obtained after pushing out the mold is annealed at high temperature in a tube furnace, sintered at 1200 ° C for 7 hours, and sintered in an oxygen atmosphere to form a high-density nanocrystalline GaFeO ₃ ceramic target with a stable structure material, so as to obtain a nanocrystalline low-temperature strong ferromagnetic GaFeO ₃ ceramic target;

4) Put the GaFeO ₃ ceramic target obtained in step 3 on the PLD target tray, use single crystal Si (111) as the substrate, evacuate to 3×10 ^-5 , and heat the substrate to 700°C for deposition Use, fine-tune the leak valve to introduce O ₂ to keep the vacuum at 4×10 ^-2 Pa, open the target autobiography control software to control the autobiography rate of the target at 2.5°/s, turn on the KrF excimer laser, and adjust the laser energy To 400mJ, frequency 3Hz, turn the substrate rotary handle so that the deposition surface is facing the sputtering plume, and maintain a relatively stable state for 7.5 hours of deposition;

5) After the deposition is completed, the substrate is cooled slowly, and the cooling rate is ≤3°C/hour to prevent the nano-magnetic GaFeO ₃ from breaking due to quenching shrinkage. When it cools to room temperature, turn off the vacuum equipment and cooling equipment, and open the flange to obtain the nano-magnetic GaFeO ₃ thin films.

In step (1), the molar ratio of Fe ₂ O ₃ , Ga ₂ O ₃ and absolute ethanol is 1:1:3.5, and the mass ratio of the total mass of Fe ₂ O ₃ and Ga ₂ O ₃ to the stainless steel grinding bead is 1:4.5 , The diameter distribution of stainless steel grinding beads is: the number of stainless steel grinding beads with diameter > 1 mm is 75%, and the number of stainless steel grinding beads with diameter ≤ 1 mm is 75%.

In the step (4), the GaFeO ₃ ceramic target placed in the PLD target tray is selected to have a diameter of less than 28 mm, and the use area of single crystal Si (111) is 10 mm×10 mm.

Example 3

A preparation method of a GaFeO ₃ ceramic target material and a nano film, which is prepared by a spark plasma hot pressing sintering method, comprising the following steps:

1) Mixing ball mill, mix analytically pure Fe ₂ O ₃ and Ga ₂ O ₃ in a molar ratio of 1:1, and grind for 35 minutes. The mixed powder is uniform and no color stratification. Put the mixed powder into a stainless steel ball mill. , add anhydrous ethanol, put in stainless steel grinding beads, seal the ball mill tube and use a ball mill at room temperature for 5.2 hours at a slow speed of 80 rpm and 12.5 hours at a fast speed of 300 rpm, with an aperture of 80 mesh. The sieve separates the ball material, and it is dried at 75°C for 2.4 hours;

2) Sintering, put the dried powder into a graphite mold, and sintering with spark plasma rapidly. The pressure during the sintering process is 31Mpa, the heating rate is 85°C/min, the temperature reaches 920°C and the temperature is kept for 5.2 minutes. At room temperature, push the sintered material out of the mold;

3) The metastable phase GaFeO ₃ blank ceramic target obtained after pushing out the mold is annealed at high temperature in a tube furnace, sintered at 1200 ° C for 7.5 hours, and sintered in an oxygen atmosphere to form a high-density nanocrystalline GaFeO ₃ ceramic target with a stable structure material, so as to obtain a nanocrystalline low-temperature strong ferromagnetic GaFeO ₃ ceramic target;

4) Put the GaFeO ₃ ceramic target obtained in step 3 on the PLD target tray, use single crystal Si (111) as the substrate, evacuate to 3×10 ^-5 , and heat the substrate to 700°C for deposition Use, fine-tune the leak valve to introduce O ₂ to keep the vacuum at 4×10 ^-2 Pa, open the target autobiography control software to control the autobiography rate of the target at 3.5°/s, turn on the KrF excimer laser, and adjust the laser energy To 350mJ, frequency 3.5Hz, turn the substrate rotary handle so that the deposition surface is facing the sputtering plume, and maintain a relatively stable state for 7.2 hours of deposition;

5) After the deposition is completed, the substrate is cooled slowly, and the cooling rate is ≤3°C/hour to prevent the nano-magnetic GaFeO ₃ from breaking due to quenching shrinkage. When it cools to room temperature, turn off the vacuum equipment and cooling equipment, and open the flange to obtain the nano-magnetic GaFeO ₃ thin films.

In step (1), the molar ratio of Fe ₂ O ₃ , Ga ₂ O ₃ and absolute ethanol is 1:1:4.2, and the mass ratio of the total mass of Fe ₂ O ₃ and Ga ₂ O ₃ to the stainless steel grinding bead is 1:4.2 , The diameter distribution of stainless steel grinding beads is: the number of stainless steel grinding beads with diameter > 1mm is 28%, and the number of stainless steel grinding beads with diameter ≤ 1mm is 72%.

In the step (4), the GaFeO ₃ ceramic target placed in the PLD target tray is selected to have a diameter of less than 28 mm, and the use area of single crystal Si (111) is 10 mm×10 mm.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be Modifications or equivalent substitutions without departing from the spirit and scope of the technical solutions of the present invention should be included in the scope of the claims of the present invention.

Claims (3)

1. GaFeO₃The preparation method of the ceramic target material and the nano film is characterized in thatThe preparation method adopts a spark plasma hot-pressing sintering method and comprises the following steps:

1) mixing the materials and ball milling, and analyzing pure Fe₂O₃、Ga₂O₃Mixing according to the molar ratio of 1:1, grinding for 20-40 minutes, putting the mixed powder into a stainless steel ball-milling tank with the volume of 2L after the mixed powder is uniform and has no color layering, adding absolute ethyl alcohol, putting stainless steel grinding beads, sealing a ball-milling tube, then ball-milling at room temperature by using a ball mill, firstly ball-milling at a slow rotating speed of 80 r/min for 4-6 hours and ball-milling at a fast rotating speed of 300 r/min for 10-14 hours, separating the ball materials by using a sieve with the aperture of 50-100 meshes, and then 60-80^oC, drying for 2-4 hours;

2) sintering, placing the dried powder into a graphite die, and performing rapid hot-pressing sintering by using discharge plasma, wherein the pressure of the sintering process is 28-32MPa, and the temperature rise speed is 70-90^oC/min, keeping the temperature at 800-;

3) metastable-phase GaFeO obtained after being pushed out of a die₃A blank ceramic target material is annealed at high temperature in a tube furnace, 1100-^oC is sintered for 6 to 8 hours in an oxygen atmosphere to form high-density nanocrystalline GaFeO with a stable structure₃Ceramic target material, thereby obtaining nanocrystalline low-temperature strong ferromagnetic GaFeO₃A ceramic target material;

4) the GaFeO obtained in the step 3)₃Placing the ceramic target on a PLD target tray, using single crystal Si (111) as a substrate, and vacuumizing to 3X 10^-5Pa while heating the substrate to 700 deg.C^oC for deposition, fine-tuning leak valve and introducing O₂Maintaining the degree of vacuum at 4X 10^-2Pa, opening target self-transmission control software to control the self-transmission rate of the target to be 2-4^oTurning on a KrF excimer laser, adjusting the laser energy to 300-400mJ at the frequency of 2-4Hz, rotating a substrate rotating handle to enable the deposition surface to face the sputtering plume, and depositing for 6-8 hours in a relatively stable state;

5) after the deposition is finished, the substrate is slowly cooled, and the cooling rate is less than or equal to 3^oC/h, preventing quenching shrinkage to make nano magnetic GaFeO₃Broken and allowed to cool to roomThe vacuum equipment and the cooling equipment are closed at the temperature, and the flange is opened to obtain the nano magnetic GaFeO₃A film.

2. A GaFeO according to claim 1₃The preparation method of the ceramic target and the nano film is characterized by comprising the following steps: fe in step 1)₂O₃、Ga₂O₃The mol ratio of the Fe-B to the absolute ethyl alcohol is 1:1:3-5₂O₃、Ga₂O₃The mass ratio of the total mass to the stainless steel grinding beads is 1:3-5, the diameter distribution of the stainless steel grinding beads is as follows: the number of the stainless steel grinding beads with the diameter larger than 1mm is 20-30%, and the number of the stainless steel grinding beads with the diameter less than or equal to 1mm is 70-80%.

3. A GaFeO according to claim 1₃The preparation method of the ceramic target and the nano film is characterized by comprising the following steps: GaFeO put into the PLD target tray in the step 4)₃The ceramic target material is selected to have a diameter less than 28mm, and the using area of the single crystal Si (111) is 10mm multiplied by 10 mm.

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