Method for inducing ferroelectric properties of hafnium oxide thin films
By using Al ion implantation gradient doping and optimized annealing processes, the performance trade-off problem of hafnium oxide thin films in uniform doping was solved, resulting in hafnium oxide thin film capacitors with high polarization, low leakage current, and high reliability, suitable for high-temperature integration and low leakage current applications.
Patent Information
- Application Number
- CN202610458778.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-09
- Publication Date
- 2026-07-10
AI Technical Summary
In the prior art, Al-doped hafnium oxide thin films face a performance trade-off when uniformly doped, making it difficult to achieve precise gradient doping in the film thickness direction, which leads to a decrease in leakage current and polarization value, and ion implantation damage affects ferroelectricity.
By employing Al ion implantation combined with optimized annealing, gradient doping is constructed in the thickness direction of hafnium oxide films. By controlling the ion implantation parameters and annealing treatment, damage is transformed into a favorable stress field, achieving high polarization, low leakage current, and high reliability.
Multi-dimensional synergistic optimization of hafnium oxide thin films was achieved, including interface pinning of oxygen vacancies, surface suppression of leakage current, and stabilization of the ferroelectric phase in the intermediate layer, which improved polarization characteristics and fatigue performance, making them suitable for high-temperature integration and low-leakage applications.
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Figure CN122373376A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of microelectronic materials and devices technology, specifically relating to an Al ion implantation gradient doped hafnium oxide thin film capacitor and its preparation method. Background Technology
[0002] Hafnium oxide ferroelectric materials have become a research hotspot for next-generation non-volatile ferroelectric RAMs (FeRAMs) due to their excellent CMOS process compatibility and nanoscale ferroelectricity. Inducing the formation of metastable ferroelectric orthorhombic phases through elemental doping (such as zirconium, aluminum, silicon, lanthanum, etc.) is key to obtaining good ferroelectric performance.
[0003] Among them, Al-doped hafnium oxide (HAO) exhibits unique advantages in high-temperature integration and low-leakage applications due to its high thermal stability and wide bandgap characteristics. Currently, the mainstream doping method for HAO thin films is in-situ homogeneous doping via atomic layer deposition (ALD). However, homogeneous doping has the following limitations: a performance trade-off dilemma—while higher homogeneous Al doping can suppress leakage, it often leads to a decrease in remanent polarization, and while lower doping can maintain high polarization, it results in insufficient leakage control and fatigue resistance; and a single control dimension—homogeneous doping can only control the average concentration, and cannot perform spatially precise design of composition, stress, and band structure in the film thickness direction, thus limiting further optimization of ferroelectric properties.
[0004] Ion implantation technology has been attempted for hafnium oxide doping. However, existing techniques mainly focus on achieving doping itself to induce a phase transition, without addressing the precise gradient engineering design of the concentration distribution of the dopant element along the thickness direction. Particularly for Al, with its larger atomic radius than oxygen, how to utilize ion implantation to achieve controllable gradient doping and overcome the negative impact of implantation damage on ferroelectricity remains a technical problem to be solved in this field. Summary of the Invention
[0005] (a) Purpose of the invention
[0006] This invention aims to overcome the shortcomings of existing technologies and provide an Al ion-implanted gradient-doped hafnium oxide thin-film capacitor and its fabrication method. This method constructs a specific Al concentration gradient along the film thickness direction by precisely controlling ion implantation parameters, and, in conjunction with an optimized annealing process, transforms implantation damage into a favorable stress field, thereby achieving comprehensive performance optimization of high polarization, low leakage current, and high reliability.
[0007] (II) Technical Solution
[0008] This invention provides a method for fabricating an Al ion implanted gradient-doped hafnium oxide thin film capacitor, comprising, from bottom to top, a substrate, a bottom electrode, a ferroelectric layer, and a top electrode; wherein the ferroelectric layer is an Al ion implanted gradient-doped hafnium oxide thin film, and the Al dopant elements are distributed in a gradient along the thickness direction of the ferroelectric layer.
[0009] Preferably, the substrate layer comprises silicon, germanium, gallium arsenide, gallium nitride, gallium oxide, zinc oxide, silicon carbide, silicon oxide, aluminum oxide, silicon nitride, and strontium titanate.
[0010] Preferably, the top and bottom electrode layers include titanium nitride, tantalum nitride, hafnium nitride, tungsten, platinum, aluminum, and ruthenium oxide.
[0011] Preferably, the hafnium oxide film is a pure HfO2 film.
[0012] Preferably, the thickness of the hafnium oxide thin film is 8–50 nm.
[0013] Preferably, the thickness of the top and bottom electrode layers is 30~100nm.
[0014] Preferably, the ion implantation energy is 1–200 keV, and the implantation dose is 1 × 10⁻⁶. 12 ~1×10 16 ions / cm², injection angle is 0°~60°.
[0015] Secondly, embodiments of the present invention also provide a method for fabricating a hafnium oxide thin film capacitor, characterized in that the method includes: growing a bottom electrode, a ferroelectric layer, and a top electrode sequentially from bottom to top on a substrate, and finally performing an annealing treatment to obtain an Al ion implanted gradient-doped hafnium oxide thin film capacitor; wherein the bottom electrode and the top electrode are prepared by magnetron sputtering, and the ferroelectric layer is prepared by atomic layer deposition combined with ion implantation.
[0016] Preferably, the method specifically includes:
[0017] Step 1: Place the substrate material into the magnetron sputtering chamber. The substrate is selected as n-type heavily doped silicon; evacuate to a vacuum level of 1×10⁻⁶. -9 ~1×10 -7 Torr, then deposit the bottom electrode; after completion, pressurize to atmospheric pressure, open the chamber, and remove the first sample;
[0018] Step 2: Place the first sample into the atomic layer deposition chamber, evacuate to a vacuum level between 0.05 and 0.6 Torr, set the tray temperature to 200–300°C, the chamber temperature to 100–180°C, the precursor source bottle temperature to 100–120°C, and the pipeline temperature to 100–150°C, and wait for all temperature parameters to reach their preset values; set the atomic layer deposition formula and grow a hafnium oxide thin film; after completion, purge to atmospheric pressure, open the chamber, and remove the second sample;
[0019] Step 3: Perform Al ion implantation on the second sample. The implantation energy is 1–200 keV, and the implantation dose is 1 × 10⁻⁶. 12 ~1×10 16 The injection angle was 0° to 60°, resulting in a gradient distribution of Al dopant elements along the thickness direction of the hafnium oxide film. After completion, the third sample was removed.
[0020] Step 4: Place the third sample into the magnetron sputtering chamber and evacuate to a vacuum level of 1×10⁻⁶. -9 ~1×10 -7 Torr, then deposit the top electrode; after completion, pressurize to atmospheric pressure, open the chamber, and remove the fourth sample.
[0021] Step 5: Place the fourth sample into a rapid annealing furnace for rapid thermal annealing. The annealing temperature is 300℃~900℃, the annealing time is 30~180s, and the annealing atmosphere is N2. The purpose of the annealing treatment is to repair ion implantation damage, activate doping elements, induce the formation of ferroelectric orthorhombic phase, and convert residual lattice damage into a local stress field to stabilize the ferroelectric phase. After completion, an Al ion implantation gradient doped hafnium oxide thin film capacitor is obtained.
[0022] (III) Beneficial Effects
[0023] Compared with the prior art, the present invention has the following beneficial effects:
[0024] (1) This invention is the first to combine Al element with ion implantation process for gradient doping of hafnium oxide thin film, making full use of Al’s material advantages of high thermal stability and wide bandgap.
[0025] (2) This invention achieves multi-dimensional synergistic optimization of ferroelectric thin films by constructing a gradient distribution of Al elements in the thickness direction of hafnium oxide thin films through ion implantation: Al enriched at the interface can pin oxygen vacancies, suppress interface reactions, and reduce charge injection; Al enriched on the surface can form a wide bandgap barrier layer to suppress leakage current injected from the top electrode; and an appropriate Al concentration in the intermediate layer can ensure the stability of the ferroelectric orthorhombic phase and polarization reversal characteristics. This functional partitioning cannot be achieved by traditional uniform doping.
[0026] (3) This invention breaks through the traditional concept of regarding ion implantation damage as an unfavorable factor. Through gradient doping design and optimized annealing process, controllable lattice damage is transformed into a local stress field, which in turn helps to stabilize the ferroelectric orthorhombic phase and achieves the technical effect of "turning disadvantages into advantages".
[0027] (4) The preparation method of the present invention is flexible and controllable. By adjusting the injection energy and dosage, different gradient distributions can be achieved in different regions of the same wafer to meet the differentiated needs of different functional units in the on-chip system.
[0028] (5) The preparation method of the present invention is fully compatible with existing CMOS processes, requires no additional special equipment, is easy to industrialize and promote, and can be applied to fields such as high-density ferroelectric memory, embedded memory, and neuromorphic computing chips. Attached Figure Description
[0029] Figure 1 This is a schematic diagram of the experimental process of the present invention.
[0030] Figure 2 This is a schematic diagram of the structure of an Al ion implantation gradient doped hafnium oxide thin film capacitor provided in an embodiment of the present invention.
[0031] Figure 3 is a schematic diagram of Al ion implantation gradient doping provided in the embodiment of the present invention, wherein (a) is a Gaussian gradient formed by a single implantation and (b) is a bimodal gradient formed by two implantations. Detailed Implementation
[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.
[0033] Please see Figure 2 This invention provides an Al-ion implanted gradient-doped hafnium oxide thin-film capacitor, comprising, from bottom to top: a substrate, a bottom electrode, a ferroelectric layer, and a top electrode. The ferroelectric layer 300 is an Al-ion implanted gradient-doped hafnium oxide thin film, with the Al dopant elements distributed in a gradient along the thickness direction of the ferroelectric layer 300. Thus, through the Al-ion gradient doping design, compositional gradients, band gradients, and stress gradients can be constructed along the film thickness direction, achieving multi-dimensional synergistic optimization of interface oxygen vacancies pinning, surface leakage current suppression, and intermediate layer stabilization of the ferroelectric phase, thereby improving the polarization characteristics, leakage current characteristics, and fatigue performance of the hafnium oxide thin film. As shown in Figure 3, the single-implantation Gaussian gradient distribution and the double-implantation bimodal gradient distribution are suitable for different performance optimization objectives.
[0034] In one embodiment, the substrate layer includes silicon, germanium, gallium arsenide, gallium nitride, gallium oxide, zinc oxide, silicon carbide, silicon oxide, aluminum oxide, silicon nitride, and strontium titanate.
[0035] In one embodiment, the top and bottom electrode layers include titanium nitride, tantalum nitride, hafnium nitride, tungsten, platinum, aluminum, and ruthenium oxide.
[0036] In one embodiment, the hafnium oxide film is a pure HfO2 film.
[0037] In one embodiment, the thickness of the hafnium oxide thin film is 8–50 nm.
[0038] In one embodiment, the thickness of the top and bottom electrode layers is preferably 30~100nm.
[0039] In one embodiment, the gradient distribution is a continuous or abrupt change in Al doping concentration along the film thickness direction, including surface enrichment, interface enrichment, intermediate layer enrichment, or combinations thereof. Surface enrichment refers to a higher Al concentration near the top electrode, interface enrichment refers to a higher Al concentration near the bottom electrode, and intermediate layer enrichment refers to a higher Al concentration in the middle of the film.
[0040] In one embodiment, the gradient distribution is achieved through an ion implantation process. Referring to Figure 3, different gradient distribution morphologies can be achieved by adjusting the implantation energy and the number of implantations. As shown in Figure 3(a), a single-energy implantation is used, leveraging the Gaussian distribution characteristics of Al ions in the thin film to form a Gaussian gradient enriched in the intermediate layer. As shown in Figure 3(b), two implantations with different energies are used, and the superposition of these energies forms a bimodal gradient distribution in both near-surface and near-interface enriched regions.
[0041] In one embodiment, the ion implantation energy is 1–200 keV, and the implantation dose is 1 × 10⁻⁶. 12 ~1×10 16 ions / cm², injection angle is 0°~60°.
[0042] A second aspect of the present invention provides a method for fabricating an Al ion implantation gradient-doped hafnium oxide thin film capacitor, the method comprising: growing a bottom electrode, a ferroelectric layer, and a top electrode sequentially from bottom to top on a substrate, and finally performing an annealing treatment to obtain an Al ion implantation gradient-doped hafnium oxide thin film capacitor; wherein the bottom electrode and the top electrode are prepared by magnetron sputtering, and the ferroelectric layer is prepared by atomic layer deposition combined with ion implantation.
[0043] Specifically, the method includes the following steps:
[0044] Step 1: Place the substrate material into the magnetron sputtering chamber. The substrate is selected as n-type heavily doped silicon; evacuate to a vacuum level of ×10⁻⁶. -9 ~1×10 -7 The magnetron sputtering process begins, followed by the deposition of a TiN bottom electrode with a thickness of 30–100 nm. The deposition time is adjusted according to the thickness of the bottom electrode. After magnetron sputtering deposition is complete, the chamber is filled to atmospheric pressure, opened, and the first sample is removed.
[0045] Step 2: Set the temperature parameters for atomic layer deposition: tray temperature 200–300℃, chamber temperature 100–180℃, precursor source bottle temperature 100–120℃, and pipeline temperature 100–150℃. Open the chamber and place the first sample into the atomic layer deposition chamber, waiting for deposition. Close the chamber and evacuate to a vacuum level between 0.05 and 0.6 Torr, waiting for the temperature parameters to reach the preset values; set the atomic layer deposition formulation and grow a hafnium oxide film with a thickness of 8–50 nm; after completion, purge to atmospheric pressure, open the chamber, and remove the second sample.
[0046] Specifically, the atomic layer deposition formulation includes: using tetraethylmethylaminohafnium (TEMA-Hf) as the hafnium source and H2O or O3 as the oxygen source. For the hafnium source, the pulse time is 0.1–0.5 s and the purge time is 20–60 s; for the oxygen source, the pulse time is 0.1–0.5 s and the purge time is 20–60 s, and the number of cycles is determined according to the required film thickness.
[0047] Step 3: Perform Al ion implantation on the second sample. The implantation energy is 1–200 keV, and the implantation dose is 1 × 10⁻⁶. 12 ~1×10 16 The injection angle is 0° to 60°, which allows the Al dopant elements to form a gradient distribution along the thickness direction of the hafnium oxide film. After completion, the third sample is taken out.
[0048] Specifically, the gradient distribution refers to a continuous or abrupt change in Al doping concentration along the film thickness direction, including surface enrichment, interface enrichment, intermediate layer enrichment, or combinations thereof. Different gradient distribution morphologies can be achieved by controlling the implantation energy and the number of implantations. When using a single energy implantation, the Gaussian distribution characteristics of Al ions are utilized to form an intermediate layer enrichment gradient distribution; when using multiple implantations at different energies, surface enrichment, interface enrichment, or bimodal gradient distributions are formed through energy superposition.
[0049] Step 4: Place the third sample into the magnetron sputtering chamber and evacuate to a vacuum level of 1×10⁻⁶. -9 ~1×10 -7The magnetron sputtering process is followed by the deposition of a top electrode made of TiN with a thickness of 30–100 nm. The deposition time is adjusted according to the thickness of the top electrode. After the magnetron sputtering deposition is completed, the chamber is filled to atmospheric pressure, opened, and the fourth sample is removed.
[0050] Step 5: Place the fourth sample into a rapid annealing furnace for rapid thermal annealing at a temperature of 300℃ to 900℃ for 30 to 180 seconds. The annealing atmosphere is N2, O2, Ar, or a mixture thereof, which allows the thin film to crystallize rapidly, resulting in an Al ion implanted gradient-doped hafnium oxide thin film capacitor.
[0051] Specifically, the annealing atmosphere can be selected according to different thin films, and can be N2, O2, Ar, or a mixture thereof. The purpose of annealing is to repair ion implantation damage, activate dopant elements, induce the formation of ferroelectric orthorhombic phases, and transform residual lattice damage into a localized stress field to stabilize the ferroelectric phase. Since annealing is performed after top electrode deposition, the top electrode can act as a capping layer, which helps to apply mechanical stress to the ferroelectric layer during annealing, further promoting the formation of the ferroelectric orthorhombic phase.
[0052] The present invention will be further described below through specific embodiments.
[0053] Example 1: Single-injection Gaussian gradient distribution
[0054] This embodiment provides a method for fabricating a hafnium oxide thin-film capacitor by Al ion implantation gradient doping, specifically including the following steps:
[0055] Step 1: Place the heavily doped n-type silicon substrate into the magnetron sputtering chamber and evacuate to 1×10⁻⁶. -8 Torr was used to sputter and deposit a 50 nm thick TiN bottom electrode; after completion, the pressure was increased to atmospheric pressure, and the first sample was removed.
[0056] Step 2: Set the atomic layer deposition parameters: tray temperature 250℃, chamber temperature 150℃, precursor source bottle temperature 110℃, and pipe temperature 130℃. Place the first sample into the ALD chamber, evacuate to 0.3 Torr, and set the atomic layer deposition formula: TEMA-Hf pulse 0.4s, purge 50s, H2O pulse 0.4s, purge 60s, cycle 100 times, depositing a 10 nm thick HfO2 film; after completion, remove the second sample.
[0057] Step 3: Perform Al ion implantation on the second sample at an implantation energy of 30 keV and an implantation dose of 5 × 10⁻⁶. 14 ions / cm², implantation angle 7°, forming a Gaussian gradient doping enrichment in the intermediate layer; after completion, the third sample is removed.
[0058] Step 4: Place the third sample into the magnetron sputtering chamber and evacuate to 1×10⁻⁶. -8 Torr, sputter deposit of a 60 nm thick TiN top electrode; after completion, the fourth sample was removed.
[0059] Step 5: Place the fourth sample in a rapid annealing furnace, evacuate to 0.1 hPa, introduce N2 atmosphere, raise the temperature to 600℃ at a heating rate of 25℃ / s, hold for 60s, and then allow it to cool naturally to room temperature to obtain an Al ion implanted gradient doped hafnium oxide thin film capacitor.
[0060] Example 2: Two-stage injection of bimodal gradient distribution
[0061] This embodiment is basically the same as Embodiment 1, except that two different energies are used in step three: first, 10 keV and 2×10 keV are injected. 14 Injection of ions / cm², followed by 50 keV, 3×10 14 The implantation of ions / cm² creates a bimodal gradient doping distribution in near-surface and near-interface enrichment regions.
[0062] Comparative Example 1: Undoped HfO2 capacitor
[0063] This comparative example is basically the same as Example 1, except that step three, ion implantation, is not performed, thus obtaining an undoped HfO2 thin film capacitor.
[0064] This invention provides an Al ion implantation gradient doped hafnium oxide thin film capacitor and its preparation method, such as... Figure 1 As shown in Figure 3, the structure comprises, from bottom to top, a substrate, a bottom electrode, a ferroelectric layer, and a top electrode. The ferroelectric layer is a hafnium oxide thin film with Al ion implantation and gradient doping, where the Al dopant elements are distributed in a gradient along the thickness direction of the ferroelectric layer. Thus, as shown in Figure 3, through the gradient doping design of Al ions, compositional gradients, band gradients, and stress gradients can be constructed along the film thickness direction. This achieves multi-dimensional synergistic optimization, including Al enrichment at the interface to pin oxygen vacancies, Al enrichment on the surface to form a wide bandgap barrier layer, and appropriate Al concentration in the intermediate layer to stabilize the ferroelectric phase. This suppresses leakage current channels caused by oxygen vacancies and improves the polarization characteristics and fatigue performance of the hafnium oxide thin film. The process of this invention is simple, compatible with CMOS processes, and conducive to commercial applications. It should be understood that the above specific embodiments of this invention are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of this invention should be included within the protection scope of this invention. Furthermore, the appended claims are intended to cover all variations and modifications that fall within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.
Claims
1. A method for inducing ferroelectric properties of hafnium oxide thin films, characterized in that, It includes, from bottom to top, a substrate, a bottom electrode, a ferroelectric layer, and a top electrode; wherein, the ferroelectric layer is a hafnium oxide thin film with Al ion implantation gradient doping, and the Al dopant elements are distributed in a gradient along the thickness direction of the ferroelectric layer.
2. The hafnium oxide thin-film capacitor as described in claim 1, characterized in that, The substrate layer includes silicon, germanium, gallium arsenide, gallium nitride, gallium oxide, zinc oxide, silicon carbide, silicon oxide, aluminum oxide, silicon nitride, and strontium titanate.
3. The hafnium oxide thin-film capacitor as described in claim 1, characterized in that, The materials of the bottom electrode and the top electrode are independently selected from titanium nitride, tantalum nitride, hafnium nitride, tungsten, platinum, aluminum, and ruthenium oxide.
4. The hafnium oxide thin-film capacitor as described in claim 1, characterized in that, The hafnium oxide film is a pure HfO2 film.
5. The hafnium oxide thin-film capacitor as described in claim 1, characterized in that, The thickness of the bottom electrode and the top electrode is independently 30–100 nm.
6. The hafnium oxide thin-film capacitor as described in claim 1, characterized in that, The thickness of the ferroelectric layer is 8–50 nm.
7. The hafnium oxide thin-film capacitor as described in claim 1, characterized in that, The gradient distribution refers to the continuous or stepwise change of Al doping concentration in the direction of film thickness, including surface enrichment, interface enrichment, intermediate layer enrichment, or combinations thereof.
8. The hafnium oxide thin-film capacitor as claimed in claim 1, characterized in that, The gradient distribution is achieved through ion implantation. The ion implantation uses a single energy implantation to form an intermediate layer enriched gradient distribution by utilizing the Gaussian distribution characteristics of Al ions; or it uses multiple implantations with different energies to form a surface-enriched, interface-enriched, or bimodal gradient distribution by superimposing the energies.
9. The hafnium oxide thin-film capacitor as described in claim 8, characterized in that, The ion implantation energy is 1–200 keV, and the implantation dose is 1 × 10⁻⁶. 12 ~1×10 16 ions / cm², injection angle is 0°~60°.
10. A method for fabricating a hafnium oxide thin-film capacitor by Al ion implantation gradient doping, characterized in that, The method includes: growing a bottom electrode, a ferroelectric layer, and a top electrode sequentially from bottom to top on a substrate, and finally performing an annealing treatment to obtain an Al ion-implanted gradient-doped hafnium oxide thin film capacitor; wherein the bottom electrode and the top electrode are prepared by magnetron sputtering, and the ferroelectric layer is prepared by atomic layer deposition combined with ion implantation.
11. The manufacturing method as described in claim 10, characterized in that, The method specifically includes: Step 1: Place the substrate material into the magnetron sputtering chamber. The substrate is selected as n-type heavily doped silicon; evacuate to a vacuum level of 1×10⁻⁶. -9 ~1×10 -7 Torr, then deposit the bottom electrode; after completion, pressurize to atmospheric pressure, open the chamber, and remove the first sample; Step 2: Place the first sample into the atomic layer deposition chamber, evacuate to a vacuum level between 0.05 and 0.6 Torr, set the tray temperature to 200–300°C, the chamber temperature to 100–180°C, the precursor source bottle temperature to 100–120°C, and the pipeline temperature to 100–150°C, and wait for all temperature parameters to reach their preset values; set the atomic layer deposition formula and grow a hafnium oxide thin film; after completion, purge to atmospheric pressure, open the chamber, and remove the second sample; Step 3: Perform Al ion implantation on the second sample. The implantation energy is 1–200 keV, and the implantation dose is 1 × 10⁻⁶. 12 ~1×10 16 The injection angle was 0° to 60°, resulting in a gradient distribution of Al dopant elements along the thickness direction of the hafnium oxide film. After completion, the third sample was removed. Step 4: Place the third sample into the magnetron sputtering chamber and evacuate to a vacuum level of 1×10⁻⁶. -9 ~1×10 -7 Torr, then deposit the top electrode; after completion, pressurize to atmospheric pressure, open the chamber, and remove the fourth sample; Step 5: Place the fourth sample into a rapid annealing furnace for rapid thermal annealing at a temperature of 300℃ to 900℃ for 30 to 180 seconds in an annealing atmosphere of N2 to rapidly crystallize the thin film and obtain a ferroelectric layer. After completion, take out the fifth sample to obtain an Al ion implanted gradient doped hafnium oxide thin film capacitor.
12. The manufacturing method as described in claim 11, characterized in that, The atomic layer deposition formulation described in step two includes: using tetraethylmethylaminohafnium as the hafnium source and H2O or O3 as the oxygen source; the hafnium source pulse time is 0.1–0.5 s and the purge time is 20–60 s; the oxygen source pulse time is 0.1–0.5 s and the purge time is 20–60 s; the number of cycles is determined according to the required film thickness.
13. The manufacturing method as described in claim 11, characterized in that, The gradient distribution mentioned in step three refers to the continuous or stepwise change of Al doping concentration in the direction of film thickness, including surface enrichment, interface enrichment, intermediate layer enrichment, or a combination thereof.
14. The manufacturing method as described in claim 11, characterized in that, In step three, ion implantation can be performed using a single energy injection to form an intermediate layer enriched gradient distribution by utilizing the Gaussian distribution characteristics of Al ions; or multiple different energy injections can be performed to form a surface-enriched, interface-enriched, or bimodal gradient distribution through energy superposition.