Method for improving capacitor performance through nitrogen-containing plasma treatment and high-density capacitor
By treating the interface between the electrode layer and the dielectric layer of the high-density capacitor with nitrogen-containing plasma, the problems of interface reaction and oxygen vacancy are solved, the stability and dielectric properties of the capacitor are improved, and it is suitable for large-scale manufacturing.
Patent Information
- Application Number
- CN202511051949.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-29
- Publication Date
- 2025-10-10
AI Technical Summary
Existing high-density capacitors have dielectric degradation problems caused by interfacial reactions and oxygen vacancies at the interface, resulting in unstable performance and decreased dielectric properties. Existing improvement solutions have process complexity and compatibility issues.
The interface between the electrode layer and the dielectric layer is treated by nitrogen-containing plasma treatment, including using nitrogen-containing gas for plasma treatment before and after deposition growth to inhibit interface reaction and reduce oxygen vacancy concentration.
It effectively improves the interface stability and dielectric properties of the capacitor, reduces the impact of the "dead layer", improves the crystal quality and frequency response characteristics of the dielectric layer, and is suitable for large-scale manufacturing.
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Figure CN120769508A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of high-density capacitor manufacturing, and more specifically, to: 1. a method for improving capacitor performance by nitrogen-containing plasma treatment; 2. a high-density capacitor obtained by using the method for improving capacitor performance by nitrogen-containing plasma treatment. Background Art
[0002] As a key component in electronic devices, high-density capacitors have been widely used in mobile communication equipment, high-performance computing platforms and other advanced electronic systems due to their excellent performance such as small size, large capacitance and fast response speed.
[0003] However, in practical applications, existing high-density capacitors still face key technical bottlenecks in terms of performance. The first is the problem of interface reaction and "dead layer": In traditional capacitor structures, there is often obvious chemical reaction or physical diffusion behavior between the electrode and the dielectric film, which easily forms a "dead layer" or interface layer with a low dielectric constant at the interface. These non-ideal interface structures not only weaken the overall capacitance density, but also cause problems such as increased leakage current and decreased voltage linearity, severely limiting the stability and consistency of device performance. The second is the dielectric degradation effect caused by oxygen vacancies: Oxide dielectric films can contain a large number of oxygen vacancy defects. On the one hand, oxygen vacancies interfere with the crystallization quality of the film, resulting in a decrease in the dielectric constant of the dielectric layer; on the other hand, they also induce oxygen vacancy-related dielectric relaxation behavior, causing the dielectric performance to drop sharply under high-frequency conditions. This frequency dependence not only impairs the filtering and decoupling capabilities of the capacitor, but also affects its reliability in high-frequency applications.
[0004] There are currently some improvement solutions for the above-mentioned problems of high-density capacitors, such as intercalation design, replacement of electrode materials, and regulation of oxygen flux and annealing processes. However, there are still many shortcomings: intercalation design may introduce additional interface complexity and may lead to an increase in film thickness; electrode material replacement faces process compatibility issues; oxygen flux control and annealing processes often have narrow process windows and complex operations, making it difficult to meet the requirements of advanced manufacturing nodes for ultra-thin films and high performance.
[0005] Therefore, there is an urgent need for a processing method that can take into account multiple requirements (1. Simple process; 2. Good compatibility; 3. Simultaneous solution to interface stability and oxygen vacancy defect problems) to achieve performance breakthroughs for the next generation of high-density capacitors. Summary of the Invention
[0006] Based on this, it is necessary to address the problem of the lack of existing processing methods that can take into account multiple requirements, and provide a method for improving capacitor performance through nitrogen-containing plasma treatment and a high-density capacitor.
[0007] The present invention is achieved by adopting the following technical solutions:
[0008] In a first aspect, the present invention discloses a method for improving capacitor performance by nitrogen-containing plasma treatment, comprising the following steps:
[0009] S1, performing plasma treatment on the interface between the bottom electrode layer and the dielectric layer of the high-density capacitor using nitrogen-containing gas.
[0010] This method of improving capacitor performance through nitrogen-containing plasma treatment implements the method or process according to an embodiment of the present disclosure.
[0011] In a second aspect, the present invention discloses a high-density capacitor, which is obtained by using the method for improving capacitor performance by nitrogen-containing plasma treatment as disclosed in the first aspect.
[0012] The nitride intercalation-based oxidation-resistant capacitor implements a method or process according to an embodiment of the present disclosure.
[0013] Compared with the prior art, the present invention has the following beneficial effects:
[0014] 1. The present invention proposes a method of using nitrogen-containing gas to perform plasma treatment on the interface between the electrode layer and the dielectric layer of a high-density capacitor. This method has the advantages of being simple, efficient, compatible, and process-controllable. It effectively improves the electrical performance and stability of high-density capacitors, and solves the performance degradation problems caused by poor interface stability and oxygen vacancy defects that are common in existing high-density capacitors. It is suitable for large-scale manufacturing and can meet the growing demand for capacitor performance in the new generation of electronic devices.
[0015] 2. The present invention uses nitrogen-containing gas to perform plasma treatment on the interface between the electrode layer and the dielectric layer of the high-density capacitor, thereby effectively suppressing the interface reaction, reducing the impact of the "dead layer", effectively reducing the oxygen vacancy concentration, improving the crystal quality and frequency response characteristics of the dielectric layer, and effectively improving the comprehensive performance indicators of the device. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0017] Figure 1 A schematic diagram of a method for improving capacitor performance through nitrogen-containing plasma treatment provided by the present invention;
[0018] Figure 2A schematic diagram of another method provided by the present invention for improving capacitor performance through nitrogen-containing plasma treatment;
[0019] Figure 3 The experimental comparison results provided by the present invention Figure 1 ;
[0020] Figure 4 The experimental comparison results provided by the present invention Figure 2 ;
[0021] Figure 5 The experimental comparison results provided by the present invention Figure 3 ;
[0022] Figure 6 The experimental comparison results provided by the present invention Figure 4 ;
[0023] Figure 7 The experimental comparison results provided by the present invention Figure 5 . DETAILED DESCRIPTION
[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0025] It should be noted that when a component is referred to as being "mounted on" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be a central component. When a component is considered to be "fixed to" another component, it may be directly fixed to the other component or there may be a central component.
[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.
[0027] As described in the background technology, as long as there is an interface between the electrode layer and the dielectric layer in a high-density capacitor (which can be planar, three-dimensional pillar-type, or trench-type), if it is not treated, interface reactions and "dead layer" problems as well as dielectric degradation effects caused by oxygen vacancies are likely to occur.
[0028] Embodiment
[0029] First of all, it should be noted that the high-density capacitor structure is generally designed as follows: it includes, from bottom to top, a bottom electrode layer, a dielectric layer, and a top electrode layer. The bottom electrode layer and the top electrode layer are made of electrode materials, such as any one of TiN, TaN, Ru, W, Pt, etc. The dielectric layer is made of oxide materials, such as any one of HfO2, ZrO2, HZO, Al2O3, TiO2, BaTiO3, SrTiO3, etc.
[0030] That is, there are actually two interfaces in the high-density capacitor: the interface between the bottom electrode layer and the dielectric layer, and the interface between the dielectric layer and the top electrode layer. Then, the oxidation reaction at the interface between the bottom electrode layer and the dielectric layer should be avoided first of all - because the influence of the oxidation reaction at this position on the performance of the capacitor is the most obvious. If necessary, the oxidation reaction at the interface between the top electrode layer and the dielectric layer can also be avoided further - because the oxidation reaction at this position also has more or less influence on the performance of the capacitor.
[0031] Then, the present application provides two methods for improving the performance of the capacitor by using nitrogen-containing plasma treatment.
[0032] Referring to Figure 1 , the first method includes the following steps:
[0033] S1, using a nitrogen-containing gas to perform plasma treatment on the interface between the bottom electrode layer and the dielectric layer of the high-density capacitor.
[0034] Referring to Figure 2 , the second method includes the following steps:
[0035] S1, using a nitrogen-containing gas to perform plasma treatment on the interface between the bottom electrode layer and the dielectric layer of the high-density capacitor;
[0036] S2, using a nitrogen-containing gas to perform plasma treatment on the interface between the dielectric layer and the top electrode layer of the high-density capacitor.
[0037] Considering that the current processing method of the high-density capacitor is to process layer by layer from bottom to top, the above-mentioned S1 and S2 can also be compatible with it. Then, S1 and S2 can be designed as follows:
[0038] I. S1 includes: before depositing and growing the dielectric layer, using a nitrogen-containing gas to perform plasma treatment on the surface of the bottom electrode layer.
[0039] After the S1 treatment, a nitrogen-rich environment is formed on the surface of the bottom electrode layer, which significantly reduces the reaction activity between the electrode and the dielectric, inhibits the reaction between the bottom electrode layer and the dielectric layer, and thus inhibits the formation of a "dead layer" or interface layer with a low dielectric constant, which helps to improve the interface dielectric consistency, stabilize the capacitance value, improve the slope of the KV (i.e., the relationship between dielectric constant and voltage) curve, reduce the secondary voltage coefficient of the device, and improve the voltage linearity.
[0040] II. Combination Figure 2 S2 includes: after the dielectric layer is deposited and grown and before the top electrode layer is deposited and grown, using a nitrogen-containing gas to perform plasma treatment on the surface of the dielectric layer.
[0041] After S2 treatment, N elements are doped into the surface of the dielectric layer and fill oxygen vacancies, effectively reducing the oxygen vacancy concentration, inhibiting the dielectric relaxation phenomenon introduced by oxygen vacancies, maintaining a higher dielectric constant at the operating frequency, and improving the dielectric crystal quality, electrical properties and uniformity, thereby improving high-frequency performance and energy storage capacity, and enhancing the filtering and decoupling capabilities of the device.
[0042] It should be noted that since plasma treatment is based on nitrogen-containing gas, it is necessary not only to ensure the treatment effect, but also to ensure the feasibility and safety of the treatment process.
[0043] Therefore, the nitrogen-containing gas mentioned above can be any one of nitrogen, a gas containing amino functional groups (commonly ammonia), or a mixture of nitrogen and a gas containing amino functional groups. These nitrogen-containing gases have a high safety factor and are easily available. The plasma treatment temperature is 200-400°C, the power is 50-2000W, and the treatment time is 1-30 minutes. The plasma excitation method used in the plasma treatment is any one of radio frequency excitation, microwave excitation, and DC glow discharge excitation.
[0044] The following is a detailed description of the process flow for high-density capacitors obtained by combining method 2:
[0045] A) Obtain a layer of electrode material and use it as the bottom electrode layer.
[0046] It should be noted that existing electrodes (TiN is recommended) can be used as the bottom electrode layer. Alternatively, the bottom electrode layer can be obtained by deposition growth on a substrate: first clean the silicon wafer substrate, then deposit and grow a layer of electrode material (TiN is recommended, with a thickness of generally 6nm to 10nm) on the silicon wafer substrate (PEALD process is recommended, with the temperature controlled at 200°C) to serve as the bottom electrode layer.
[0047] B) Use nitrogen-containing gas (nitrogen or ammonia is recommended) to perform plasma treatment on the surface of the bottom electrode layer (radio frequency excitation is recommended, the treatment temperature is recommended to be 400°C, the treatment power is recommended to be 2000W, and the treatment time is recommended to be 5 minutes).
[0048] C) A layer of oxide material (HZO is recommended, with a thickness of generally 6nm to 10nm) is deposited and grown (ALD process is recommended, and the temperature is controlled at 250°C) on the bottom electrode layer treated in B) as a dielectric layer, and is subjected to rapid thermal annealing treatment in a protective gas atmosphere (annealing temperature is controlled at 300-700°C).
[0049] It should be noted that in this embodiment, the dielectric layer growth rate is controlled at about The annealing temperature is controlled at about 400°C and the annealing time is controlled at about 1 minute.
[0050] D) Use nitrogen-containing gas (nitrogen or ammonia is recommended) to perform plasma treatment on the surface of the dielectric layer (RF excitation is recommended, the treatment temperature is recommended to be 400°C, the treatment power is recommended to be 2000W, and the treatment time is recommended to be 5 minutes).
[0051] E) A layer of electrode material (TiN is recommended, with a thickness of 6nm to 10nm) is deposited and grown (PEALD process is recommended, with the temperature controlled at 200°C) on the dielectric layer treated in D) and serves as the top electrode layer; thus, a high-density capacitor with improved performance is obtained.
[0052] Of course, the deposition growth process involved in this method can be selected from ALD process, PEALD process, PVD process, MOCVD process, ebeam process, PECVD process, and sputter process according to actual conditions, but it is necessary to ensure that the deposition growth effect meets the requirements.
[0053] As can be seen from the above examples, the method of the present invention is well compatible with the existing high-density capacitor manufacturing process, does not introduce additional complex structures or high-cost steps, supports implementation on conventional semiconductor equipment platforms, has a good process window and controllability, and is highly adaptable.
[0054] Experimental verification
[0055] In order to prove the effect of the present invention, this embodiment 2 conducts an experimental comparison between a high-density capacitor that has not been treated by the above method and a high-density capacitor that has been treated by the above method, and examines the relevant performance indicators. The results are as follows: Figures 3 to 7As shown: the curve corresponding to w / o treatment in the figure is the result of the high-density capacitor without the above method treatment; the curve corresponding to NH3 plasma in the figure is the result of the high-density capacitor treated by the above method.
[0056] Referring to Figure 3 , which is the dielectric constant ratio of the two; referring to Figure 4 , which is the leakage current ratio of the two. It can be seen that although only S1 treatment is performed, the capacitor still achieves a significant increase in dielectric constant, while the leakage current does not increase.
[0057] Referring to Figure 5 , which is the K-V curve comparison of the two; referring to Figure 6 , which is the K-f (i.e. dielectric constant and frequency response) curve comparison of the two; referring to Figure 7 , which is the K0-f (i.e. dielectric constant normalized value and frequency response) curve comparison of the two. It can be seen that after S1 and S2 treatment, the K-V curve of the capacitor is more symmetrical, and the degree of inclination is significantly improved; the dielectric constant and frequency response of the capacitor are improved, and a more stable dielectric constant can be achieved in a higher frequency range.
[0058] In combination with Figures 3 to 7 It can be seen that the method can improve the performance of the capacitor and is feasible and effective.
[0059] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as limiting the scope of the patent. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of the present application. Therefore, the protection scope of the present application patent should be subject to the appended claims.
Claims
1. A method for improving capacitor performance by nitrogen-containing plasma treatment, characterized in that: It includes the following steps: S1, performing plasma treatment on the interface between the bottom electrode layer and the dielectric layer of the high-density capacitor using nitrogen-containing gas.
2. The method for improving capacitor performance by nitrogen-containing plasma treatment according to claim 1, wherein: S1 includes: Before depositing the growing dielectric layer, the surface of the bottom electrode layer is plasma treated using a nitrogen-containing gas.
3. The method for improving capacitor performance by nitrogen-containing plasma treatment according to claim 1, wherein: The following steps are also included: S2, performing plasma treatment on the interface between the dielectric layer and the top electrode layer of the high-density capacitor using a nitrogen-containing gas.
4. The method for improving capacitor performance by nitrogen-containing plasma treatment according to claim 3, wherein S2 include: After the dielectric layer is deposited and grown and before the top electrode layer is deposited and grown, a nitrogen-containing gas is used to perform plasma treatment on the surface of the dielectric layer.
5. The method for improving capacitor performance by nitrogen-containing plasma treatment according to any one of claims 1 to 4, characterized in that: The nitrogen-containing gas is any one of nitrogen, a gas containing an amino functional group, and a mixed gas of nitrogen and a gas containing an amino functional group.
6. The method for improving capacitor performance by nitrogen-containing plasma treatment according to claim 3, wherein: Gases containing amino functional groups include: ammonia.
7. The method for improving capacitor performance by nitrogen-containing plasma treatment according to any one of claims 1 to 4, characterized in that: The temperature of the plasma treatment is 200-400° C., the power is 50-3000 W, and the treatment time is 1-30 minutes.
8. The method for improving capacitor performance by nitrogen-containing plasma treatment according to any one of claims 1 to 4, characterized in that: The plasma excitation method used in the plasma treatment is any one of radio frequency excitation, microwave excitation, and direct current glow discharge excitation.
9. A high-density capacitor, characterized in that: The capacitor is obtained by treating the capacitor using a method for improving capacitor performance by treating the capacitor with nitrogen-containing plasma as described in any one of claims 1 to 8.
10. The high-density capacitor according to claim 9, characterized in that It includes from top to bottom: bottom electrode layer, dielectric layer, top electrode layer; Wherein, the material of the bottom electrode layer is any one of TiN, TaN, Ru, W, and Pt; The materials of the dielectric layer are HfO2, ZrO2, Hf x Zr 1-x Any one of O2, Al2O3, TiO2, BaTiO3, SrTiO3; The material of the top electrode layer is any one of TiN, TaN, Ru, W, and Pt.