Y-doped HfO2 diluted magnetic semiconductor film preparation method and spintronic device

Abstract

The present invention provides a Y-doped HfO2 diluted magnetic semiconductor film preparation method and a spintronic device, the method comprising: placing a Y-doped HfO2 target material at a radio frequency target position corresponding to a radio frequency device; fixing a yttrium-stabilized zirconia substrate on a substrate fixing platform; pre-sputtering the Y-doped HfO2 target material for a specified time by a radio frequency device; determining the glow condition of the Y-doped HfO2 target material, and when the glow condition indicates that the glow is stable, formally sputtering the Y-doped HfO2 target material by a radio frequency device, sputtering for a preset sputtering time at room temperature, sputtering the material on the Y-doped HfO2 target material onto the yttrium-stabilized zirconia substrate, and obtaining a Y-doped HfO2 diluted magnetic semiconductor film. The method can solve the problem of poor performance and stability of electronic devices prepared using traditional diluted magnetic semiconductor films; and improve the performance and stability of spintronic devices prepared using diluted magnetic semiconductor films.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor materials, and in particular to a method for preparing a Y-doped HfO2 diluted magnetic semiconductor film and a spintronic device. Background Art

[0002] As a key material in spin electronics, rare earth magnetic semiconductor thin films have always attracted much attention. Rare earth magnetic semiconductor thin films refer to a new type of semiconductor material formed by partially replacing non-magnetic cations with magnetic transition metal ions or rare earth metal ions in compounds such as II-VI or III-V. They have broad application prospects in the preparation of spin electronic devices such as magnetic random access memory, magnetic tunnel junction, magnetic sensor, and spin light emitting diode.

[0003] HfO2 thin films have attracted much attention as a rare earth magnetic semiconductor film. At present, HfO2-based rare earth magnetic semiconductor films include: HfO2 thin films of different thicknesses prepared on PPA substrates by DC magnetron sputtering, amorphous HfO2 nanohelical arrays prepared on Si substrates by electron beam evaporation, Co-doped HfO2 thin films of different thicknesses prepared by sol-gel method, Ni-doped HfO2 thin films prepared by low-energy Ni ion implantation HfO2 thin films, and Fe-doped HfO2 thin films.

[0004] However, the current HfO2-based diluted magnetic semiconductor films have a low saturation magnetization intensity, which leads to poor performance and stability of electronic devices made using traditional diluted magnetic semiconductor films. Summary of the invention

[0005] In view of this, an embodiment of the present invention provides a method for preparing a Y-doped HfO2 diluted magnetic semiconductor film and a spintronic device to eliminate or improve one or more defects existing in the prior art.

[0006] One aspect of the present invention provides a method for preparing a Y-doped HfO2 diluted magnetic semiconductor film, the method comprising the following steps:

[0007] Placing the Y-doped HfO2 target material at the RF target position corresponding to the RF device;

[0008] fixing the yttrium-stabilized zirconia substrate on a substrate fixing platform;

[0009] Pre-sputtering the Y-doped HfO2 target for a specified period of time by means of a radio frequency device;

[0010] Determine the glow condition of the Y-doped HfO2 target material. When the glow condition indicates that the glow is stable, formally sputter the Y-doped HfO2 target material through a radio frequency device. Sputter at room temperature for a preset sputtering time, and sputter the material on the Y-doped HfO2 target material onto a yttrium-stabilized zirconia substrate to obtain a Y-doped HfO2 diluted magnetic semiconductor film. The molecular formula of the Y-doped HfO2 diluted magnetic semiconductor film is Hf 0.93 Y 0.07 O2.

[0011] In some embodiments of the present invention, after obtaining the Y-doped HfO2 diluted magnetic semiconductor film, the method further comprises:

[0012] The Y-doped HfO2 diluted magnetic semiconductor film is annealed at a preset annealing temperature; the annealing treatment is used to enhance the magnetic anisotropy and room temperature ferromagnetism of the Y-doped HfO2 diluted magnetic semiconductor film.

[0013] In some embodiments of the present invention, the Y-doped HfO2 diluted magnetic semiconductor film is annealed at a preset annealing temperature, including:

[0014] The Y-doped HfO2 diluted magnetic semiconductor film is placed in a muffle furnace and heated to a preset annealing temperature for 200 minutes;

[0015] The Y-doped HfO2 diluted magnetic semiconductor film was annealed in air for 1200 minutes.

[0016] In some embodiments of the present invention, the preset annealing temperature includes 500°C, 600°C, 700°C, 800°C, 900°C or 1000°C.

[0017] In some embodiments of the present invention, the radio frequency device and the substrate fixing platform are arranged in a sputtering chamber; the gas pressure in the sputtering chamber is 1.3 Pascals; the power of the radio frequency device is adjusted to a preset power, the rotation speed of the substrate fixing platform is set to a preset rotation speed, and before the Y-doped HfO2 target is pre-sputtered by the radio frequency device, the method further includes:

[0018] The sputtering chamber was evacuated to a vacuum degree less than or equal to 2×10 -4 Pascal;

[0019] Argon gas was introduced into the sputtering chamber at a rate of 30 cubic centimeters per minute, and the gas pressure in the sputtering chamber was adjusted to 1.3 Pascals.

[0020] In some embodiments of the present invention, pre-sputtering a Y-doped HfO2 target material for a specified time by a radio frequency device includes:

[0021] The power of the RF device was set to 60 watts, and the Y-doped HfO2 target was pre-sputtered for 10 minutes.

[0022] In some embodiments of the present invention, the preset sputtering time is positively correlated with the thickness of the Y-doped HfO2 diluted magnetic semiconductor film, including:

[0023] The preset sputtering time is 5 minutes, and the thickness of the Y-doped HfO2 diluted magnetic semiconductor film is 5.4 nanometers; or,

[0024] The preset sputtering time is 10 minutes, and the thickness of the Y-doped HfO2 diluted magnetic semiconductor film is 27 nanometers; or,

[0025] The preset sputtering time is 20 minutes, and the thickness of the Y-doped HfO2 diluted magnetic semiconductor film is 56 nanometers; or,

[0026] The preset sputtering time is 30 minutes, and the thickness of the Y-doped HfO2 diluted magnetic semiconductor film is 98 nanometers.

[0027] In some embodiments of the present invention, the distance between the Y-doped HfO2 target and the yttrium-stabilized zirconia substrate is 90 mm; and the orientation of the yttrium-stabilized zirconia substrate is 111 crystal orientation.

[0028] In some embodiments of the present invention, the Y-doped HfO2 target is a 2-inch diameter 7% Y-doped HfO2 ceramic target with a molecular formula of Hf 0.93 Y 0.07 O2.

[0029] Another aspect of the present invention provides a spin electronic device, which is a spin electronic device prepared using the above-mentioned Y-doped HfO2 diluted magnetic semiconductor film.

[0030] The Y-doped HfO2 diluted magnetic semiconductor film preparation method and spin electronic device of the present invention are as follows: placing a Y-doped HfO2 target material at a radio frequency target position corresponding to a radio frequency device; fixing a yttrium-stabilized zirconia substrate on a substrate fixing platform; pre-sputtering the Y-doped HfO2 target material for a specified time by using a radio frequency device; determining the glow condition of the Y-doped HfO2 target material, and when the glow condition indicates that the glow is stable, formally sputtering the Y-doped HfO2 target material by using a radio frequency device, sputtering for a preset sputtering time at room temperature, and sputtering the material on the Y-doped HfO2 target material onto the yttrium-stabilized zirconia substrate to obtain a Y-doped HfO2 diluted magnetic semiconductor film. The invention can solve the problem of poor performance and stability of electronic devices prepared by traditional dilute magnetic semiconductor films; by using yttrium as a doping element, the magnetic properties of the dilute magnetic semiconductor film are effectively regulated, the magnetic moment in the film is increased, the magnetic properties are improved, and then the saturation magnetization is enhanced, thereby improving the performance and stability of electronic devices prepared by the dilute magnetic semiconductor film; at the same time, by applying radio frequency energy through a radio frequency device, the sputtering energy of the Y-doped HfO2 target is higher, the deposition rate of the material on the substrate is increased, thereby enhancing the magnetic properties of the film, and further improving the performance and stability of electronic devices prepared by the dilute magnetic semiconductor film.

[0031] In addition, annealing the Y-doped HfO2 diluted magnetic semiconductor film can significantly improve the magnetic anisotropy and room-temperature ferromagnetism compared to the saturation magnetization intensity of the film before annealing, thereby further improving the performance and stability of electronic devices prepared from Y-doped HfO2 diluted magnetic semiconductor films.

[0032] In addition, by controlling the duration of formal sputtering and adjusting the thickness of the Y-doped HfO2 diluted magnetic semiconductor film, as the thickness of the Y-doped HfO2 diluted magnetic semiconductor film decreases, the out-of-plane saturation magnetization intensity of the Y-doped HfO2 diluted magnetic semiconductor film will increase significantly. By flexibly adjusting the film thickness, customized preparation of material properties can be achieved, which can better meet the needs of different application scenarios and improve the applicability and flexibility of electronic devices prepared from Y-doped HfO2 diluted magnetic semiconductor films.

[0033] Additional advantages, purposes, and features of the present invention will be described in part in the following description, and will become apparent to those skilled in the art after studying the following, or may be learned from the practice of the present invention. The purposes and other advantages of the present invention may be achieved and obtained by the structures specifically indicated in the specification and the accompanying drawings.

[0034] Those skilled in the art will appreciate that the objectives and advantages that can be achieved with the present invention are not limited to the above specific description, and the above and other objectives that can be achieved by the present invention will be more clearly understood from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings described herein are used to provide a further understanding of the present invention, constitute a part of the present application, and do not constitute a limitation of the present invention. In the drawings:

[0036] Figure 1 A flow chart of a method for preparing a Y-doped HfO2 diluted magnetic semiconductor thin film provided in one embodiment of the present invention;

[0037] Figure 2 Schematic diagram of out-of-plane hysteresis loops of 5.4 nm and 98 nm thick Y-doped HfO2 diluted magnetic semiconductor films provided in one embodiment of the present invention;

[0038] Figure 3 X-ray diffraction patterns of 5.4 nm and 98 nm thick Y-doped HfO2 diluted magnetic semiconductor films provided in one embodiment of the present invention;

[0039] Figure 4 A schematic diagram of an out-of-plane hysteresis loop of a 27 nm thick Y-doped HfO2 diluted magnetic semiconductor film provided in one embodiment of the present invention;

[0040] Figure 5 An X-ray diffraction pattern of a 27 nm thick Y-doped HfO2 diluted magnetic semiconductor film provided in one embodiment of the present invention;

[0041] Figure 6 A schematic diagram of the in-plane hysteresis loop of a 27 nm thick Y-doped HfO2 diluted magnetic semiconductor film provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0043] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solutions according to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0044] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, elements, steps or components, but does not exclude the presence or addition of one or more other features, elements, steps or components.

[0045] It should also be noted that, unless otherwise specified, the term “connection” herein may refer not only to a direct connection but also to an indirect connection involving an intermediate.

[0046] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

[0047] The present invention provides a method for preparing an yttrium (Y)-doped HfO2 diluted magnetic semiconductor film. The diluted magnetic semiconductor film obtained by doping HfO2 with yttrium as a doping element increases the magnetic moment in the film, improves the magnetic properties, and further enhances the saturation magnetization. The prepared Y-doped HfO2 diluted magnetic semiconductor film is applied to spin electronic devices such as magnetic random access memory, magnetic tunnel junction, magnetic sensor, spin light emitting diode, etc., which can greatly improve the performance and stability of the electronic devices.

[0048] Figure 1 FIG. 1 is a schematic flow chart of a method for preparing a Y-doped HfO2 diluted magnetic semiconductor thin film according to an embodiment of the present invention. Figure 1 As shown, the method for preparing a Y-doped HfO2 diluted magnetic semiconductor film may include the following steps S101 to S104:

[0049] Step S101, placing a Y-doped HfO2 target material at a radio frequency target position corresponding to a radio frequency device.

[0050] Y-doped HfO2 refers to the process of doping yttrium into hafnium oxide. Y-doped HfO2 target refers to hafnium oxide prepared as a target, which contains a certain proportion of yttrium doping. Yttrium doping can introduce additional unpaired electrons or vacancies, thereby changing the electronic structure and magnetic properties of the material, resulting in a higher saturation magnetization.

[0051] In some embodiments of the present invention, the Y-doped HfO2 target is a 7% Y-doped HfO2 ceramic target with a diameter of 2 inches and a molecular formula of Hf 0.93 Y 0.07 In actual implementation, the Y-doping ratio and the diameter of the Y-doped HfO2 target can be adjusted according to the actual requirements of thin film preparation. This embodiment does not limit the Y-doping ratio and the diameter of the Y-doped HfO2 target.

[0052] The target material is usually used as part of the electrode, and the RF voltage is applied by the RF device to sputter or excite the gas. The RF device refers to a device used to generate a radio frequency (RF) electric field during the thin film deposition process, such as an RF power supply; the RF device excites the gas or target material by applying RF voltage to generate charged particles such as ions and electrons, which interact with the target material to sputter the material on the target material.

[0053] The RF target position refers to the position where the target material is placed in the RF device. The RF target position depends on the design of the RF device. It is usually placed inside the RF device, maintaining a certain distance from the substrate and aligned with the position of the substrate.

[0054] In some embodiments of the present invention, a radio frequency device is used to apply radio frequency energy to a Y-doped HfO2 target material, thereby sputtering out a substance in the Y-doped HfO2 target material and depositing it on a surface of a Yttria-Stabilized Zirconia (YSZ) substrate to form a thin film. The orientation of the Yttria-Stabilized Zirconia substrate is a 111 crystal orientation.

[0055] Step S102, fixing the yttrium-stabilized zirconia substrate on a substrate fixing platform.

[0056] In some embodiments of the present invention, the yttrium-stabilized zirconia substrate is fixed to the center of the substrate fixing platform by heat-resistant glue, and keeps a certain distance from the Y-doped HfO2 target. The center of the substrate fixing platform can be a dial-shaped platform; in actual implementation, the yttrium-stabilized zirconia substrate can be fixed to the substrate fixing platform in other forms, such as by a clamping fixture, a mechanical bayonet or a clamping spring, etc. Correspondingly, the substrate fixing platform can also be a corresponding different mechanical fixing frame, etc.

[0057] In some embodiments of the present invention, the distance between the Y-doped HfO2 target and the yttrium-stabilized zirconia substrate is 90 mm. In actual implementation, the distance between the yttrium-stabilized zirconia substrate and the Y-doped HfO2 target can be adjusted according to the actual requirements of thin film preparation. This embodiment does not limit the distance between the yttrium-stabilized zirconia substrate and the Y-doped HfO2 target.

[0058] In addition, the dial was polished clean with sandpaper, and the (111)-oriented YSZ substrate was fixed to the center of the dial using heat-resistant glue.

[0059] In some embodiments of the present invention, in order to ensure that the sputtered material from the Y-doped HfO2 target can be evenly deposited on the surface of the yttrium-stabilized zirconia substrate, and at the same time enable the sputtered material to cover the entire substrate surface more quickly and improve the preparation efficiency of the thin film, the substrate fixing platform can be controlled to rotate according to specific preparation requirements to achieve a more uniform, efficient and stable quality effect.

[0060] Step S103, pre-sputtering the Y-doped HfO2 target material for a specified time by using a radio frequency device.

[0061] In some embodiments of the present invention, a radio frequency device and a substrate fixing platform are arranged in a sputtering chamber; when pre-sputtering starts, the power of the radio frequency device is 60 watts, and the rotation speed of the substrate fixing platform is 10 revolutions per minute.

[0062] Specifically, the Y-doped HfO2 target is pre-sputtered for a specified time by a radio frequency device, including: setting the power of the radio frequency device to 60 watts, and pre-sputtering the Y-doped HfO2 target for 10 minutes.

[0063] In actual implementation, the power of the RF device and the specified time of pre-sputtering can be adjusted according to the specific characteristics of the Y-doped HfO2 target and the required pre-sputtering effect, for example, the RF power value can be reduced by 45 watts or the pre-sputtering time can be extended to 15 minutes. This embodiment does not limit the value of the power of the RF device and the specified time of pre-sputtering.

[0064] At the same time, when the pre-sputtering starts, the gas pressure in the sputtering chamber is 1.3 Pascal. Based on this, before the pre-sputtering starts, the gas pressure in the sputtering chamber needs to be adjusted to 1.3 Pascal.

[0065] In one example, the gas pressure in the sputtering chamber is adjusted to 1.3 Pa by gas irrigation and exhaust cycle. First, the gas is exhausted by a vacuum pump, and then an inert gas (such as argon) is filled into the sputtering chamber to adjust the gas pressure in the sputtering chamber.

[0066] Specifically, the power of the radio frequency device is adjusted to a preset power, the rotation speed of the substrate fixing platform is set to a preset rotation speed, and before the Y-doped HfO2 target is pre-sputtered by the radio frequency device, the sputtering chamber is evacuated to a vacuum degree less than or equal to 2×10 -4 Pascal; 30 cubic centimeters of argon gas per minute was introduced into the sputtering chamber, and the gas pressure in the sputtering chamber was adjusted to 1.3 Pascal.

[0067] In another example, the gas in the sputtering chamber is pumped out by a vacuum pump to adjust the gas pressure in the sputtering chamber. The types of vacuum pumps include but are not limited to mechanical pumps, diffusion pumps, molecular pumps, centrifugal pumps, etc. The pumping rate and power of the vacuum pump can be adjusted as needed to adjust the gas pressure in the sputtering chamber to 1.3 Pascals.

[0068] In yet another example, the gas pressure in the sputtering chamber can be controlled by adjusting the gas regulating valve. By gradually adjusting the opening or closing degree of the gas regulating valve, the gas pressure in the sputtering chamber can be adjusted to 1.3 Pascal.

[0069] Step S104, determine the glow condition of the Y-doped HfO2 target material, and when the glow condition indicates that the glow is stable, formally sputter the Y-doped HfO2 target material through a radio frequency device, sputter for a preset sputtering time at room temperature, and sputter the material on the Y-doped HfO2 target material onto a yttrium-stabilized zirconia substrate to obtain a Y-doped HfO2 diluted magnetic semiconductor film.

[0070] Wherein, determining the glow condition of the Y-doped HfO2 target material includes at least one of the following conditions:

[0071] The first method is to perform spectral analysis on the Y-doped HfO2 target material by using a spectral instrument, wherein the spectral instrument includes a spectrophotometer or a Raman spectrometer.

[0072] In the sputtering chamber, irradiate the Y-doped HfO2 target after pre-sputtering for a specified time and observe the glow spectrum it emits. By analyzing the spectrum with a spectrometer, the glow conditions of the Y-doped HfO2 target can be determined, including the intensity, frequency, and possible energy level transitions of the glow.

[0073] The second method is to detect the intensity and frequency changes of the glow in real time during the pre-sputtering process. If the glow shows a continuous intensity and frequency, it is determined that the glow of the Y-doped HfO2 target is stable.

[0074] The third method is to control the temperature of the Y-doped HfO2 target in the sputtering chamber and observe the glow performance. In the case that the Y-doped HfO2 target shows similar characteristics at different temperatures, it is determined that the Y-doped HfO2 target glow is stable.

[0075] When the glow condition indicates that the glow is stable, at room temperature, the Y-doped HfO2 target is formally sputtered for a preset time by a radio frequency device to sputter the material on the Y-doped HfO2 target onto the yttrium-stabilized zirconia substrate to obtain a Y-doped HfO2 diluted magnetic semiconductor film.

[0076] Among them, the preset duration is the duration of formal sputtering that is preset according to the desired thickness of the Y-doped HfO2 rare-magnetic semiconductor film. In some embodiments of the present invention, the preset sputtering duration is positively correlated with the thickness of the Y-doped HfO2 rare-magnetic semiconductor film, including: the preset sputtering duration is 5 minutes, and the thickness of the Y-doped HfO2 rare-magnetic semiconductor film is 5.4 nanometers; or, the preset sputtering duration is 10 minutes, and the thickness of the Y-doped HfO2 rare-magnetic semiconductor film is 27 nanometers; or, the preset sputtering duration is 20 minutes, and the thickness of the Y-doped HfO2 rare-magnetic semiconductor film is 56 nanometers; or, the preset sputtering duration is 30 minutes, and the thickness of the Y-doped HfO2 rare-magnetic semiconductor film is 98 nanometers.

[0077] The thickness of the Y-doped HfO2 diluted magnetic semiconductor film is regulated by the length of the formal sputtering. In some embodiments of the present invention, the thickness of the Y-doped HfO2 diluted magnetic semiconductor film is negatively correlated with the out-of-plane saturation magnetization of the Y-doped HfO2 diluted magnetic semiconductor film. In other words, as the thickness of the Y-doped HfO2 diluted magnetic semiconductor film decreases, the out-of-plane saturation magnetization of the Y-doped HfO2 diluted magnetic semiconductor film will increase significantly.

[0078] refer to Figure 2 and Figure 3 , Figure 2 The room temperature ferromagnetism of the prepared 98nm thick and 5.4nm thick Y-doped HfO2 diluted magnetic semiconductor films was measured by a vibrating sample magnetometer (VSM). The out-of-plane saturation magnetization of the 98nm thick film was 10emu / cm 3 The out-of-plane saturation magnetization of a 5.4 nm thick film is 400 emu / cm 3 , showing significant ferromagnetism at room temperature. Figure 3 These are the X-ray diffraction (XRD) patterns of 5.4nm and 98nm thick Y-doped HfO2 diluted magnetic semiconductor films.

[0079] Room temperature ferromagnetism is an important performance indicator for semiconductor films, which can affect the availability, stability and energy efficiency of materials in various applications. For example, materials with higher room temperature ferromagnetism can reduce the energy consumption of equipment, simplify the design and operation of equipment, and improve the reliability and stability of equipment. Based on this, in order to improve the room temperature ferromagnetism of Y-doped HfO2 diluted magnetic semiconductor films, it is also necessary to anneal the Y-doped HfO2 diluted magnetic semiconductor films to improve the room temperature ferromagnetism of Y-doped HfO2 diluted magnetic semiconductor films.

[0080] like Figure 4 As shown in the figure, the out-of-plane saturation magnetization of the unannealed 27nm thick Y-doped HfO2 diluted magnetic semiconductor film is 27emu / cm 3 After annealing at 900℃, the out-of-plane saturation magnetization increases to 518emu / cm 3 . Figure 5 These are the X-ray diffraction patterns of 27nm thick Y-doped HfO2 diluted magnetic semiconductor films without annealing and after annealing at 900℃.

[0081] Specifically, after obtaining the Y-doped HfO2 diluted magnetic semiconductor film, the method further includes: annealing the Y-doped HfO2 diluted magnetic semiconductor film at a preset annealing temperature; the annealing treatment is used to enhance the magnetic anisotropy and room temperature ferromagnetism of the Y-doped HfO2 diluted magnetic semiconductor film.

[0082] Among them, the preset annealing temperature is a pre-set temperature used for annealing the Y-doped HfO2 rare-earth magnetic semiconductor film. The value of the preset annealing temperature can be adjusted according to the actual room temperature ferromagnetism requirements of the Y-doped HfO2 rare-earth magnetic semiconductor film, for example, 500°C, 600°C, 700°C, 800°C, 900°C or 1000°C, etc. This embodiment does not limit the value of the preset annealing temperature.

[0083] Optionally, a muffle furnace is used to implement the annealing treatment of the Y-doped HfO2 diluted magnetic semiconductor film.

[0084] Specifically, the Y-doped HfO2 diluted magnetic semiconductor film is annealed at a preset annealing temperature, including: placing the Y-doped HfO2 diluted magnetic semiconductor film in a muffle furnace and heating it to the preset annealing temperature for 200 minutes; and annealing the Y-doped HfO2 diluted magnetic semiconductor film in air for 1200 minutes.

[0085] In actual implementation, an atmosphere controlled furnace (Atmosphere Controlled Furnace) can also be used to implement the annealing treatment of the Y-doped HfO2 diluted magnetic semiconductor film, or a rapid thermal annealing (RTA) method can be used to implement the annealing treatment of the Y-doped HfO2 diluted magnetic semiconductor film. This embodiment does not limit the implementation method of the annealing treatment of the Y-doped HfO2 diluted magnetic semiconductor film.

[0086] In some embodiments of the present invention, the Y-doped HfO2 rare-earth magnetic semiconductor film has significant magnetic anisotropy, and the percentage value of the magnetic anisotropy is defined as: (out-of-plane saturation magnetization - in-plane saturation magnetization) / out-of-plane saturation magnetization. The strength of the magnetic anisotropy is determined by the percentage value of the magnetic anisotropy. The higher the percentage value, the stronger the magnetic anisotropy. The magnetic anisotropy of the Y-doped HfO2 rare-earth magnetic semiconductor film can be significantly improved by annealing.

[0087] For example, the in-plane saturation magnetization of a 27nm thick Y-doped HfO2 diluted magnetic semiconductor film is 9.82emu / cm 3 , out-of-plane saturation magnetization is 27emu / cm 3 For example, the magnetic anisotropy percentage value is 63.63%; after annealing at a preset annealing temperature of 900°C, Figure 4 and Figure 6 As shown, the out-of-plane saturation magnetization increases to 518emu / cm 3 , the in-plane saturation magnetization is 54emu / cm 3 At this time, the magnetic anisotropy percentage value is 89.58%.

[0088] In summary, the method for preparing a Y-doped HfO2 diluted magnetic semiconductor film provided in the present embodiment comprises the following steps: placing a Y-doped HfO2 target material at a radio frequency target position corresponding to a radio frequency device; fixing a yttrium-stabilized zirconia substrate on a substrate fixing platform; pre-sputtering the Y-doped HfO2 target material for a specified time by means of a radio frequency device; determining the glow condition of the Y-doped HfO2 target material, and when the glow condition indicates that the glow is stable, formally sputtering the Y-doped HfO2 target material by means of a radio frequency device, sputtering the material on the Y-doped HfO2 target material for a preset sputtering time at room temperature, and sputtering the material on the Y-doped HfO2 target material onto the yttrium-stabilized zirconia substrate to obtain a Y-doped HfO2 diluted magnetic semiconductor film. The invention can solve the problem of poor performance and stability of electronic devices prepared by traditional dilute magnetic semiconductor films; by using yttrium as a doping element, the magnetic properties of the dilute magnetic semiconductor film are effectively regulated, the magnetic moment in the film is increased, the magnetic properties are improved, and then the saturation magnetization is enhanced, thereby improving the performance and stability of electronic devices prepared by the dilute magnetic semiconductor film; at the same time, by applying radio frequency energy through a radio frequency device, the sputtering energy of the Y-doped HfO2 target is higher, the deposition rate of the material on the substrate is increased, thereby enhancing the magnetic properties of the film, and further improving the performance and stability of electronic devices prepared by the dilute magnetic semiconductor film.

[0089] In addition, annealing the Y-doped HfO2 diluted magnetic semiconductor film can significantly improve the magnetic anisotropy and room-temperature ferromagnetism compared to the saturation magnetization intensity of the film before annealing, thereby further improving the performance and stability of electronic devices prepared from Y-doped HfO2 diluted magnetic semiconductor films.

[0090] In addition, by controlling the duration of formal sputtering and adjusting the thickness of the Y-doped HfO2 diluted magnetic semiconductor film, as the thickness of the Y-doped HfO2 diluted magnetic semiconductor film decreases, the out-of-plane saturation magnetization intensity of the Y-doped HfO2 diluted magnetic semiconductor film will increase significantly. By flexibly adjusting the film thickness, customized preparation of material properties can be achieved, which can better meet the needs of different application scenarios and improve the applicability and flexibility of electronic devices prepared from Y-doped HfO2 diluted magnetic semiconductor films.

[0091] An embodiment of the present invention further provides a spintronic device prepared using the aforementioned Y-doped HfO2 diluted magnetic semiconductor film.

[0092] It should be clear that the present invention is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present invention.

[0093] In the present invention, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with features of other embodiments or replace features of other embodiments.

[0094] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the embodiments of the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a Y-doped HfO2 diluted magnetic semiconductor film, characterized in that: The method comprises the following steps: Place the Y-doped HfO2 target at the RF target position corresponding to the RF device; the Y-doped HfO2 target is a 2-inch diameter 7% Y-doped HfO2 ceramic target with a molecular formula of Hf 0.93 Y 0.07 O2; fixing the yttrium-stabilized zirconia substrate on a substrate fixing platform; Pre-sputtering the Y-doped HfO2 target material for a specified period of time by the radio frequency device; Determine the glow condition of the Y-doped HfO2 target material, and when the glow condition indicates that the glow is stable, formally sputter the Y-doped HfO2 target material by the radio frequency device, sputter at room temperature for a preset sputtering time, and sputter the material on the Y-doped HfO2 target material onto the yttrium-stabilized zirconia substrate to obtain a Y-doped HfO2 diluted magnetic semiconductor film; After obtaining the Y-doped HfO2 diluted magnetic semiconductor film, the method further comprises: Annealing the Y-doped HfO2 diluted magnetic semiconductor film at a preset annealing temperature; the annealing treatment is used to enhance the magnetic anisotropy and room temperature ferromagnetism of the Y-doped HfO2 diluted magnetic semiconductor film; the preset annealing temperature is 900° C. or 1000° C.; The annealing treatment of the Y-doped HfO2 diluted magnetic semiconductor film according to a preset annealing temperature comprises: Placing the Y-doped HfO2 diluted magnetic semiconductor film in a muffle furnace and heating it to the preset annealing temperature for 200 minutes; The Y-doped HfO2 diluted magnetic semiconductor film is annealed in air for 1200 minutes.

2. The method according to claim 1, characterized in that: The radio frequency device and the substrate fixing platform are arranged in a sputtering chamber; the gas pressure of the sputtering chamber is 1.3 Pascals; the power of the radio frequency device is adjusted to a preset power, the rotation speed of the substrate fixing platform is set to a preset rotation speed, and before the Y-doped HfO2 target is pre-sputtered by the radio frequency device, the method further includes: The sputtering chamber is evacuated to a vacuum degree less than or equal to 2×10 -4 Pascal; Argon gas was introduced into the sputtering chamber at a flow rate of 30 cubic centimeters per minute, and the gas pressure in the sputtering chamber was adjusted to 1.3 Pascals.

3. The method according to claim 1, characterized in that The pre-sputtering of the Y-doped HfO2 target material by the radio frequency device for a specified time period includes: The power of the RF device was set to 60 watts, and the Y-doped HfO2 target was pre-sputtered for 10 minutes.

4. The method according to claim 1, characterized in that: The preset sputtering time is positively correlated with the thickness of the Y-doped HfO2 diluted magnetic semiconductor film, including: The preset sputtering time is 5 minutes, and the thickness of the Y-doped HfO2 diluted magnetic semiconductor film is 5.4 nanometers; or, The preset sputtering time is 10 minutes, and the thickness of the Y-doped HfO2 diluted magnetic semiconductor film is 27 nanometers; or, The preset sputtering time is 20 minutes, and the thickness of the Y-doped HfO2 diluted magnetic semiconductor film is 56 nanometers; or, The preset sputtering time is 30 minutes, and the thickness of the Y-doped HfO2 diluted magnetic semiconductor film is 98 nanometers.

5. The method according to claim 1, characterized in that The distance between the Y-doped HfO2 target and the yttrium-stabilized zirconia substrate is 90 mm; the orientation of the yttrium-stabilized zirconia substrate is (111).

6. A spin electronic device, characterized in that: The spin electronic device is a spin electronic device prepared by using the Y-doped HfO2 diluted magnetic semiconductor thin film preparation method described in any one of claims 1 to 5.

Images