A rare earth doped nanostructured silicon-based electroluminescent device and a method of making the same

Abstract

The application discloses a rare earth doped nano-structure silicon-based electroluminescent device and a preparation method thereof. The device is prepared by atomic layer deposition technology to prepare a nano-layer structure electroluminescent film doped with 0.5-5 nm interval rare earth monatomic layer. A nano-scale ultrathin rare earth ion doped area serves as a light emitting layer, and an undoped pure matrix interval layer area serves as an overheated electron acceleration layer, so that the conduction band electrons collide with the light emitting layer after being fully accelerated to obtain higher energy in the undoped acceleration area. The service life of the electroluminescent device adopting the nano-layer material is increased by more than 100 times, the quantum efficiency of the rare earth ion light emission can be more than 40%, and the excitation cross section of the electroluminescence reaches the level of a III-V semiconductor LED with the same emission wavelength. The rare earth doped silicon-based electroluminescent device can be used for developing a micro optical amplifier and a laser directly electrically pumped in a photonic integrated chip, and is a new scheme for solving the problem that a silicon photonic chip lacks an integrable light source.

Description

Technical Field

[0001] This invention belongs to the field of electroluminescence, specifically relating to a rare-earth-doped nanostructured silicon-based electroluminescent device and its fabrication method. Background Technology

[0002] Because silicon, the material used in integrated circuit manufacturing, has an indirect bandgap electronic structure, its luminous efficiency is very low. The lack of high-efficiency silicon-based light-emitting materials has long been a bottleneck problem in the development of integrated optoelectronics. The rapidly developing fields of optoelectronics, quantum mechanics, and optical communication urgently need high-efficiency, low-power lasers and optical amplifiers that can be massively integrated within a chip. Currently, these miniaturized silicon-based light sources are mainly lasers and amplifiers that integrate III-V semiconductors with silicon waveguides. However, silicon-based III-V hybrid light sources have complex processes, are incompatible with silicon CMOS technology, have high power consumption, and can only be integrated on a small scale. Rare-earth luminescent materials are abundant, have a wide emission wavelength range, long excited-state lifetimes, and are easy to achieve low-threshold population inversion. Rare-earth-doped optical waveguide amplifiers and lasers have low power consumption, low loss, low noise, high bandwidth, good thermal stability, polarization insensitivity, and low cost, and are compatible with silicon integrated photonics and CMOS technologies. Compact rare-earth-doped optical waveguide amplifiers operating in small-signal and unsaturated states have already been commercially produced. However, rare-earth-doped silicon-based light sources still cannot operate independently of the pumping of III-V semiconductor lasers, and there has been no breakthrough in electric pumping.

[0003] In recent years, research on rare-earth-doped silicon-based electroluminescent devices has mainly focused on two directions: The first is silicon-based carrier-injection recombination MIS junction devices, using rare-earth-doped nanocrystalline silicon, ZnO, GaN, TiO2, etc. as luminescent materials. These devices have low operating voltages and good luminous stability, but low luminous efficiency. The second is MOS LEDs based on the field-luminescence principle, using rare-earth-doped dielectric materials such as ZnS, SiO2, Al2O3, GaN, and Ga2O3. Compared to III-V semiconductor LEDs, they have similar external quantum efficiencies, but operating voltages are 20-50 times higher, and operating current density and power consumption per unit area are three to four orders of magnitude lower. Rare-earth-doped thin-film electroluminescent devices are more suitable for low-power integrated photonic systems and display devices.

[0004] Current thin-film electroluminescent devices typically use a single luminescent material with uniform doping. This results in the overlap of overheated electron acceleration transport and collisional luminescence processes in time and space. The electrical transport and collisional luminescence processes compete and restrict each other, leading to low electroluminescence efficiency, easy device breakdown, and difficulty in synergistically improving the efficiency and stability of electroluminescence. Summary of the Invention

[0005] In view of the above shortcomings, this invention provides a rare-earth-doped silicon-based thin-film electroluminescent device and its fabrication method. Atomic layer deposition (ALD) is used to fabricate a 0.5-5 nm spacing rare-earth single-atom-layer doped nanolayer electroluminescent thin film. The ultrathin rare-earth ion-doped region at the single-atom-layer scale serves as the luminescent layer, while an undoped pure matrix spacer layer serves as an overheated electron accelerating layer. Conduction band electrons are first fully accelerated in the undoped accelerating region to obtain higher energy before colliding with the luminescent layer. By independently optimizing the performance of the luminescent layer and the overheated electron accelerating layer, the disadvantage of mutual constraint between electron acceleration and collisional luminescence processes in traditional uniformly doped luminescent materials can be overcome, synergistically improving the efficiency and electrical injection stability of electroluminescence. Simultaneously, based on the layered dielectric electrostatic field theory, a breakdown-resistant nano-dielectric protective layer composed of materials with complementary dielectric properties is designed. Using the aforementioned rare-earth single-atom-layer doped nano-luminescent material and nanocomposite dielectric material can effectively overcome the concentration quenching effect of rare-earth luminescence in traditional thin-film electroluminescent devices, increase the average energy of overheated electrons, actively suppress local avalanche breakdown effects, and thus improve the efficiency, stability, and uniformity of electroluminescence. Compared to electroluminescent devices fabricated from traditional single materials, those using nanolayered materials exhibit a lifetime increase of over 100 times, a quantum efficiency of over 40% for rare-earth ion luminescence, and an excitation cross-section comparable to that of III-V group semiconductor LEDs with the same emission wavelength. These rare-earth-doped silicon-based electroluminescent devices can be applied to the development of directly electrically pumped micro-optical amplifiers and lasers in photonic integrated chips, representing a novel solution to the lack of integrable light sources for silicon photonic chips.

[0006] To achieve the above-mentioned technical effects, the present invention employs the following technical means:

[0007] This invention first discloses a method for fabricating a rare-earth-doped nanostructured silicon-based electroluminescent device, comprising:

[0008] (1) Select a silicon substrate, wherein the silicon substrate material is selected from any one of the following: (100) orientation n-type silicon substrate, high temperature resistant indium tin oxide (ITO) glass, or quartz glass coated with a transparent conductive layer;

[0009] (2) Using the atomic layer deposition method, a rare earth monoatom layer periodically doped oxide light-emitting layer is deposited on the surface of the silicon substrate described in step (1);

[0010] (3) The rare earth monolayer periodically doped oxide light-emitting layer deposited in step (2) is subjected to high-temperature annealing to activate the rare earth light-emitting ions therein.

[0011] (4) A nanocomposite dielectric protective layer is deposited on the oxide light-emitting layer after high-temperature annealing in step (3) using atomic layer deposition method;

[0012] (5) On the side of the nanocomposite dielectric protective layer away from the substrate in step (4), a surface transparent electrode is prepared;

[0013] (6) Photolithography is performed on the transparent surface electrode described in step (5) to prepare surface electrodes of different sizes and shapes;

[0014] (7) On the back side of the silicon substrate described in step (1), a back aluminum electrode is prepared;

[0015] (8) Alloy anneal the back aluminum electrode described in step (7) to form an ohmic contact between the aluminum electrode and the silicon substrate.

[0016] (9) Through the above eight steps, a silicon-based electroluminescent device is obtained from bottom to top as follows: a transparent surface electrode (1), a nanocomposite dielectric protective layer (2), a rare earth single-atom layer periodically doped oxide light-emitting layer (3), a silicon substrate (4), and a back aluminum electrode (5). The transparent surface electrode (1), the nanocomposite dielectric protective layer (2), and the rare earth single-atom layer periodically doped oxide light-emitting layer (3) are all prepared by atomic layer deposition. The back aluminum electrode and the silicon substrate form an ohmic contact.

[0017] Further, the material used in the nanocomposite dielectric protective layer in step (2) is selected from any one of the following: nano Al2O3 / TiO2, ZrO2 / TiO2, HfO2 / TiO2, Al2O3 / Ta2O5, Al2O3 / Ta2O5, and Ga2O3 / TiO2 composite dielectric materials, and the thickness of the two dielectric materials is between 2-8 nm respectively;

[0018] The nanocomposite protective layer was prepared by periodic deposition using atomic layer deposition (ALD) technology.

[0019] (2.1) In each deposition cycle, the thickness of the low dielectric constant material is controlled to be 2-3 nm and the thickness of the high dielectric constant material is controlled to be 6-8 nm;

[0020] (2.2) By adjusting the deposition cycle ratio of low dielectric constant material and high dielectric constant material, the thickness ratio of the two is controlled at 1:4 to 1:3;

[0021] (2.3) The final nanocomposite dielectric protective layer has a total stack thickness of 50-300 nm, and the breakdown electric displacement vector of the nanocomposite dielectric protective layer is more than 1.5 times larger than the breakdown electric displacement vector of the oxide light-emitting layer with periodic doping of rare earth single atom layer.

[0022] Further, the matrix material of the rare earth single-atom layer periodically doped oxide light-emitting layer in step (2) includes: Ge2O3, Sc2O3, Lu2O3, ZnO, Al2O3, Ga2O3, Y2O3, SiO2, TiO2, SnO2, ZrO2, GeO2, and Gd2O3; the doping adopts an atomic layer spacing doping mode with a doping spacing of 0.3-5 nm and an average doping concentration of 0.1-5%;

[0023] The rare earth oxides in the periodically doped oxide light-emitting layer of the rare earth single-atom layer in step (2) include: CeO2, Er2O3, Yb2O3, Sm2O3, Eu2O3, Dy2O3, Ho2O3, Tm2O3, Gd2O3, and Tb2O3. The total thickness of the periodically doped oxide thin film light-emitting layer of the rare earth single-atom layer is 30-150 nm, and the doping period interval is 0.5-5 nm.

[0024] The thermal annealing temperature of the periodically doped oxide luminescent layer of the deposited rare earth monolayer in step (2) is 700-900℃, using a N2 protective atmosphere, for 1-2 hours.

[0025] Furthermore, the precursor source of the rare earth organic complex in the periodically doped rare earth monolayer light-emitting layer is Re(2,2,6,6-tetramethyl-3,5-heptadecane)3; wherein:

[0026] Re includes: Er, Yb, Eu, Dy, Tb, Ho, Tm, Ce, Gd, the reaction gas is ozone (O3) or H2O, and the deposition temperature is 300-400℃.

[0027] Furthermore, the periodically doped oxide light-emitting layer with rare-earth single-atom layer distribution is prepared by the following method:

[0028] Nanocomposite luminescent films were grown using atomic layer deposition (ALD) technology, with a rare-earth-doped single-atom layer as the luminescent layer and an undoped pure matrix material spacer layer as the electron accelerator layer. The average doping concentration of rare earth elements was controlled through two deposition modes.

[0029] (1) The thickness of the electron acceleration layer is fixed at 3 nm, and the rare earth oxide doping amount is adjusted within the range of 1-4 atomic layer deposition cycles to determine the thickness of the light-emitting layer.

[0030] (2) Fixed deposition mode (1) The thickness of rare earth doped layer is determined, and the spacing thickness of the doped layer is precisely changed in the range of 0.5-5nm to determine the thickness of electron acceleration layer.

[0031] Furthermore, in the periodically doped oxide light-emitting layer with rare earth single-atom layers, 1-3 molecular layers of luminescent sensitizing material are inserted on both sides of the rare earth single-atom doped layer to improve the local environment and effective doping concentration of rare earth ions, thereby increasing the stability and luminescence efficiency of electroluminescence.

[0032] Furthermore, the surface transparent electrode described in step (5) is prepared using the following method:

[0033] (5.1) Using a zinc-containing compound as the zinc source and an aluminum-containing compound as the aluminum source, or using an indium-tin compound as the indium-tin source, or using a gallium-containing compound as the gallium source and performing n-type doping, prepare a precursor for the corresponding transparent conductive layer material;

[0034] (5.2) Using water vapor as the reactant gas, the precursor described in step (1) is deposited on the substrate surface using atomic layer deposition.

[0035] (5.3) When preparing an aluminum-doped zinc oxide (ZnO:Al) transparent conductive layer, the deposition cycle ratio of the zinc source to the aluminum source is controlled to be 23:1;

[0036] (5.4) Through the above deposition process, a nanoscale, highly uniform transparent conductive layer is formed on the substrate surface. The transparent conductive layer material is selected from at least one of aluminum-doped zinc oxide (ZnO:Al), indium tin oxide (ITO), or n-type doped gallium oxide (Ga2O3).

[0037] Further, the zinc-containing compound in step (5.1) is diethylzinc, and the aluminum-containing compound is trimethylaluminum; the thickness of the aluminum-doped zinc oxide transparent conductive layer in step (5.5) is 120-200 nm.

[0038] Further, the formation of an ohmic contact between the back aluminum electrode and the silicon substrate in step (8) specifically includes: performing aluminum-silicon alloying treatment using a vacuum thermal annealing method, with an annealing temperature of 400°C, a vacuum degree of less than 1E-3 Torr, and a time of 20-60 minutes.

[0039] The present invention also discloses a rare earth-doped nanostructured silicon-based electroluminescent device prepared according to any of the above-described preparation methods.

[0040] The device technology route of the present invention

[0041] The process involves: standard RCA cleaning of an N-type semiconductor silicon wafer → ALD growth of a light-emitting layer → high-temperature heat treatment in an atmosphere → ALD growth of a dielectric protective layer → ALD growth of a transparent electrode layer → front-side photolithography of the transparent electrode layer → back-side vacuum thermal evaporation of the Al electrode → vacuum heat treatment to form an ohmic contact.

[0042] This invention uses a unified ALD (Alternating Discharge) system to grow rare-earth-doped nanolayered light-emitting films, High-k composite dielectric layers, and transparent electrode layers in light-emitting devices, ensuring growth precision and simplifying the device fabrication process. To reduce cross-contamination, the composite light-emitting layer and dielectric protective layer are grown using separate ALD systems, while the low-resistivity transparent electrode layer requires deposition using a separate ALD system.

[0043] The beneficial effects of this invention are as follows:

[0044] This invention provides a method for fabricating rare-earth single-atom-layer distributed doped nanolayered composite luminescent materials and devices. It employs organometallic compounds as precursor sources and utilizes two or more oxides with complementary photoelectric properties to construct nanocomposite electroluminescent materials and high-dielectric-constant dielectric materials. Electrons are pre-accelerated in a pure, undoped spacer region to obtain sufficiently high energy before collisionally exciting the rare-earth-doped ultrathin luminescent layer. This allows for independent layer-by-layer optimization and control of the accelerated transport and luminescence performance of overheated electrons, while simultaneously increasing the average energy of overheated electrons, increasing the concentration and collision excitation cross-section of effective rare-earth luminescent centers, and suppressing cross-relaxation and local avalanche breakdown effects. This significantly improves the quantum efficiency and stability of the rare-earth-doped silicon substrate electroluminescent device. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the process flow for the device obtained by the present invention, wherein: 1 is the standard RCA cleaning process for silicon substrate; 2 is the atomic layer deposition growth of the light-emitting layer; 3 is the high-temperature annealing of the light-emitting layer in a nitrogen atmosphere; 4 is the atomic layer deposition growth of the nanocomposite dielectric protective layer; 5 is the atomic layer deposition growth of the transparent conductive film; 6 is the photolithographic transparent electrode; 7 is the deposition of the back aluminum metal electrode; and 8 is the alloying annealing of the back electrode.

[0046] Figure 2 The diagram shows the structure of the device, where: 1 is a transparent electrode, 2 is a nanocomposite dielectric protective layer grown by atomic layer deposition, 3 is a periodically doped oxide thin film light-emitting layer with rare earth single-atom layer distribution, 4 is a silicon substrate, and 5 is a back aluminum electrode.

[0047] Figure 3 The image shows a cross-sectional transmission electron microscope (TEM) image of the device, where: 1 is the nanocomposite dielectric protective layer, and 2 is the light-emitting layer with periodic doping of rare earth single-atom layers.

[0048] Figure 4 The images show color electroluminescent devices doped with different rare earth ions, where: 1 is Al2O3:Eu; 2 is Al2O3:Tb; and 3 is Al2O3:Tm.

[0049] Figure 5This is a high-efficiency and stable rare-earth erbium ion-doped Ga2O3 electroluminescent device, wherein: 1 is a cross-sectional image of transmission electron microscopy, 2 is the infrared emission spectrum of the device and an image of the device during emission, 3 is the relationship between the infrared electroluminescence power density of the device and the injection current, 4 is a schematic diagram of the current transport and emission excitation process of the electroluminescent device, 5 is the relationship between the external quantum efficiency of the device and the injection current, and 6 is the relationship between the luminescence intensity and aging time under a constant current aging condition of 100 μA. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Example 1

[0052] Rare-earth single-atom-layer doped nanolayered silicon-based color electroluminescent devices

[0053] All thin films in the silicon composite gate MOSLED were fabricated using atomic layer deposition (ALD) technology. The substrate used was a 4-inch n-type substrate. <100> A single-crystal silicon wafer with a resistivity of 2-5 Ω·cm was used. The nanolayered Al₂O₃ / Er₂O₃ luminescent layer was obtained by alternating growth of x periods of Al₂O₃ and y periods of Er₂O₃. The aluminum and erbium precursor sources were trimethylaluminum (TMA) and europium 2,2,6,6-tetramethyl-3,5-heptadecylene diketone acid [Eu(THD)₃], terbium 2,2,6,6-tetramethyl-3,5-heptadecylene diketone acid [Tb(THD)₃], respectively. The purity of thulium 2,2,6,6-tetramethyl-3,5-heptadecylene diketone acid [Tm(THD)₃] was 99.99%, respectively. Ozone was used as the oxygen source. At a substrate temperature of 350℃, the growth rates of Al₂O₃ and Tb₂O₃ were respectively... and The thickness and average doping concentration of each thin film can be precisely controlled by varying the number of atomic layer periods and their ratio. The total thickness of the Al₂O₃ / Er₂O₃ emitting layer in the electroluminescent device is 40-200 nm. All the aforementioned Al₂O₃ / Er₂O₃ emitting films were heat-treated at 850°C for 1 hour under a N₂ atmosphere. Then, a 100-200 nm TiO₂ / Al₂O₃ high-k nanocomposite dielectric protective layer and a 100-200 nm ZnO:Al transparent conductive film were alternately grown on the emitting layer using the ALD method. Finally, a transparent conductive electrode was formed by photolithography, and an Al back electrode was deposited by vapor deposition, thus fabricating a complete silicon-based composite thin film MOS structure color LED device. Figure 2This is a schematic cross-sectional view of the device. Figure 3 This is a transmission electron microscope (TEM) image of the cross-section of the device. Figure 4 Photograph of a color electroluminescent device under a microcurrent of 10 microamps.

[0054] Example 2

[0055] Rare-earth single-atom-layer doped Ga2O3:Er nanolayer structure silicon-based infrared and green electroluminescent devices

[0056] The substrate is a 4-inch n-type <100> A single-crystal silicon wafer with a resistivity of 2-5 Ω·cm was used. The nanolayered Ga₂O₃ / Er₂O₃ light-emitting layer was obtained by alternating growth of x periods of Ga₂O₃ and y periods of Er₂O₃. The gallium and erbium precursor sources were triethylgallium (TMA) and terbium 2,2,6,6-tetramethyl-3,5-heptadecyl diketone [Er(THD)₃], respectively, both with a purity of 99.99%, and ozone was used as the oxygen source. At a substrate temperature of 350℃, the growth rates of Al₂O₃ and Er₂O₃ were respectively... and The thickness and average doping concentration of each thin film layer are precisely controlled by adjusting the number of atomic layer periods and their ratio. The total thickness of the Ga2O3 / Er2O3 emitting layer in the electroluminescent device is 40-200 nm. All the above Ga2O3 / Er2O3 emitting films are heat-treated at 850℃ for 1 hour in a N2 atmosphere to activate rare earth ion luminescence. Then, a 100-200 nm TiO2 / Al2O3 high-k nanocomposite dielectric protective layer and a 100-200 nm ZnO:Al transparent conductive film are alternately grown on the emitting layer using the ALD method. Finally, a transparent conductive electrode is formed by photolithography, and an Al back electrode is deposited by vapor deposition to fabricate a complete silicon-based composite thin film MOS structure LED device. Figure 5 The main electroluminescence performance of the device is as follows: The peak emission spectrum of the device is in the 1.53-micron fiber optic communication band, the maximum external quantum efficiency of emission is 36%, and after 100 hours of constant current aging, the emission intensity only decays to 90% of the initial value.

[0057] The above description of the embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for fabricating a rare-earth-doped nanostructured silicon-based electroluminescent device, comprising: (1) Select a silicon substrate, wherein the silicon substrate material is selected from either (100) oriented n-type silicon substrate or quartz glass coated with a transparent conductive layer; (2) Using atomic layer deposition, a rare earth monolayer periodically doped oxide light-emitting layer is deposited on the surface of the silicon substrate described in step (1). The matrix material of the rare earth monolayer periodically doped oxide light-emitting layer includes: Ge2O3, Sc2O3, Lu2O3, ZnO, Al2O3, Ga2O3, Y2O3, SiO2, TiO2, SnO2, ZrO2, GeO2, and Gd2O3. The doping adopts an atomic layer spacing doping mode with a doping spacing of 0.3-5 nm and an average doping concentration of 0.1-5%. The rare earth oxides in the periodically doped oxide light-emitting layer with rare earth single-atom layer distribution include: CeO2, Er2O3, Yb2O3, Sm2O3, Eu2O3, Dy2O3, Ho2O3, Tm2O3, Gd2O3, and Tb2O3; the total thickness of the periodically doped oxide thin film light-emitting layer with rare earth single-atom layer distribution is 30-150 nm, and the doping period interval is 0.5-5 nm; (3) The rare earth single-atom layer periodically doped oxide light-emitting layer deposited in step (2) is subjected to high-temperature annealing to activate the rare earth light-emitting ions therein; the heat annealing temperature of the deposited rare earth single-atom layer periodically doped oxide light-emitting layer is 700-900℃, with N2 protective atmosphere, for 1-2 hours. (4) A nanocomposite dielectric protective layer is deposited on the oxide luminescent layer after high-temperature annealing in step (3) using atomic layer deposition method; (5) On the side of the nanocomposite dielectric protective layer away from the substrate in step (4), a surface transparent electrode is prepared; (6) Perform photolithography on the surface transparent electrode described in step (5) to prepare surface transparent electrodes of different sizes and shapes; (7) On the back side of the silicon substrate described in step (1), a back aluminum electrode is prepared; (8) Alloy anneal the back aluminum electrode described in step (7) to form an ohmic contact between the aluminum electrode and the silicon substrate; Through the above eight steps, a silicon-based electroluminescent device is obtained from top to bottom as follows: a transparent surface electrode (1), a nanocomposite dielectric protective layer (2), a rare earth single-atom layer periodically doped oxide light-emitting layer (3), a silicon substrate (4), and a back aluminum electrode (5). The transparent surface electrode (1), the nanocomposite dielectric protective layer (2), and the rare earth single-atom layer periodically doped oxide light-emitting layer (3) are all prepared by atomic layer deposition. The back aluminum electrode forms an ohmic contact with the silicon substrate.

2. The preparation method according to claim 1, wherein: The material used in the nanocomposite dielectric protective layer in step (4) is selected from any one of the following: nano Al2O3 / TiO2, ZrO2 / TiO2, HfO2 / TiO2, Al2O3 / Ta2O5, and Ga2O3 / TiO2 composite dielectric materials, and the thickness of the two dielectric materials is between 2-8 nm respectively; The nanocomposite protective layer was prepared by periodic deposition using atomic layer deposition (ALD) technology. (2.1) In each deposition cycle, the thickness of the low dielectric constant material is controlled to be 2-3 nm and the thickness of the high dielectric constant material is controlled to be 6-8 nm; (2.2) By adjusting the deposition cycle ratio of low dielectric constant material and high dielectric constant material, the thickness ratio of the two is controlled at 1:4~1:3; (2.3) The final nanocomposite dielectric protective layer has a total stack thickness of 50-300 nm, and the breakdown electric displacement vector of the nanocomposite dielectric protective layer is more than 1.5 times larger than the breakdown electric displacement vector of the oxide light-emitting layer with periodic doping of rare earth single atom layer.

3. The preparation method according to claim 1, wherein: In step (2), the precursor source of the rare earth organic complex in the periodically doped oxide luminescent layer with rare earth monolayer distribution is Re(2,2,6,6-tetramethyl-3,5-heptadecane)3; wherein: Re includes: Er, Yb, Eu, Dy, Tb, Ho, Tm, Ce, Gd, the reaction gas is ozone (O3) or H2O, and the deposition temperature is 300-400℃.

4. The preparation method according to claim 1, wherein: Step (2) The periodically doped oxide light-emitting layer with rare earth single-atom layer distribution is prepared by the following method: Nanocomposite luminescent films were grown using atomic layer deposition (ALD) technology, with a rare-earth-doped single-atom layer as the luminescent layer and an undoped pure matrix material spacer layer as the electron accelerator layer. The average doping concentration of rare earth elements was controlled through two deposition modes. (1) The thickness of the electron acceleration layer is fixed at 3 nm, and the rare earth oxide doping amount is adjusted within the range of 1-4 atomic layer deposition cycles to determine the thickness of the light-emitting layer. (2) Fixed deposition mode (1) The thickness of rare earth doped layer is determined, and the spacing thickness of the doped layer is precisely changed in the range of 0.5-5nm to determine the thickness of electron acceleration layer.

5. The preparation method according to claim 4, wherein: In the periodically doped oxide light-emitting layer with rare earth single-atom layers, 1-3 molecular layers of luminescent sensitizing material are inserted on both sides of the rare earth single-atom doped layer to improve the local environment and effective doping concentration of rare earth ions, thereby increasing the stability and luminescence efficiency of electroluminescence.

6. The preparation method according to claim 1, wherein: The transparent electrode mentioned in step (5) is prepared by the following method: (5.1) Using a zinc-containing compound as the zinc source and an aluminum-containing compound as the aluminum source, or using an indium-tin compound as the indium-tin source, or using a gallium-containing compound as the gallium source and performing n-type doping, prepare a precursor for the corresponding transparent conductive layer material; (5.2) Using water vapor as the reactant gas, the precursor described in step (5.1) is deposited on the substrate surface using atomic layer deposition. (5.3) When preparing an aluminum-doped zinc oxide (ZnO:Al) transparent conductive layer, the deposition cycle ratio of the zinc source to the aluminum source is controlled to be 23:1; Through the above deposition process, a nanoscale, highly uniform transparent conductive layer is formed on the substrate surface. The transparent conductive layer material is selected from at least one of aluminum-doped zinc oxide (ZnO:Al), indium tin oxide (ITO), or n-type doped gallium oxide (Ga2O3).

7. The preparation method according to claim 6, wherein: The zinc-containing compound in step (5.1) is diethylzinc, and the aluminum-containing compound is trimethylaluminum; The thickness of the aluminum-doped zinc oxide (ZnO:Al) transparent conductive layer in step (5.3) is 120-200 nm.

8. The preparation method according to claim 1, wherein: Step (8) involves forming an ohmic contact between the back aluminum electrode and the silicon substrate, specifically by performing aluminum-silicon alloying treatment using a vacuum thermal annealing method. The annealing temperature is 400°C, the vacuum degree is less than 1E-3 Torr, and the time is 20-60 minutes.

9. A rare-earth-doped nanostructured silicon-based electroluminescent device prepared by the preparation method according to any one of claims 1 to 8.

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