Cylindrical capacitor and forming method thereof
By designing a cylindrical capacitor, using a hard layer with a harderness higher than other layers and an oxidized surface portion treated with ozone, the challenges of high capacitance and low leakage of capacitors in semiconductor devices are solved, and the structural stability and capacitance value are improved.
Patent Information
- Application Number
- CN202411324461.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-03-27
- Filing Date
- 2024-09-23
- Publication Date
- 2025-09-30
AI Technical Summary
As semiconductor device sizes shrink, capacitors face challenges in maintaining high capacitance and reducing leakage.
A cylindrical capacitor is designed, comprising a first electrode having a hollow cylindrical shape, a surface portion of the electrode being oxidized, a dielectric layer, and a second electrode. A hard layer having a higher hardness than other layers is formed on the surface of the electrode to enhance structural stability, and an oxidized surface portion is formed by ozone treatment to reduce leakage.
The hardness of the capacitor is improved, leakage is reduced, structural collapse is avoided, and the capacitance value is increased.
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Figure CN120731005A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a cylindrical capacitor and a method for forming the same. Background Art
[0002] Capacitors are widely used in semiconductor devices, such as dynamic random access memory (DRAM). However, as semiconductor devices become smaller, achieving higher capacitance and reducing leakage in capacitors becomes increasingly challenging. Therefore, there is a need to develop a capacitor and its fabrication method that satisfies these requirements. Summary of the Invention
[0003] The present disclosure provides a cylindrical capacitor. The cylindrical capacitor includes a first electrode, a dielectric layer, and a second electrode. The first electrode has a hollow cylindrical shape, wherein the first electrode includes multiple oxidized surface portions, multiple first metal-containing layers, and a first hard layer. The oxidized surface portions are located on multiple cylindrical surfaces of the hollow cylinder of the first electrode. The first metal-containing layer is located between the oxidized surface portions. The first hard layer is disposed between the first metal-containing layers, and the hardness of the first hard layer is greater than the combined hardness of the oxidized surface portions and the first metal-containing layers. The dielectric layer is disposed on the first electrode. The second electrode is disposed on the dielectric layer.
[0004] In some embodiments, the first hard layer includes a silicon layer, a carbon layer, an aluminum layer, or a combination thereof.
[0005] In some embodiments, the first metal-containing layer includes titanium nitride, titanium silicon nitride, or a combination thereof, and the oxidized surface portion includes titanium oxynitride, titanium oxide, titanium silicon oxynitride, or a combination thereof.
[0006] In some embodiments, the first hard layer is located at a plurality of distances from the cylindrical surfaces of the hollow cylinder of the first electrode that are 0.4 to 0.6 times the thickness of the first electrode.
[0007] In some embodiments, the thickness of the first electrode is to
[0008] In some embodiments, the ratio of the thickness of the first hard layer to the total thickness of the oxidized surface portions to the first metal-containing layers is 0.02 to 0.3.
[0009] In some embodiments, the first hard layer is separated from the oxidized surface portion by a first metal-containing layer.
[0010] In some embodiments, the oxidized surface portion is in direct contact with the dielectric layer, and the first metal-containing layer and the first hard layer are separated from the dielectric layer by the oxidized surface portion.
[0011] In some embodiments, the thickness of each of these oxidized surface portions is to
[0012] In some embodiments, the second electrode includes a plurality of second metal-containing layers and a second hard layer between the second metal-containing layers, and a hardness of the second hard layer is greater than a plurality of hardnesses of the second metal-containing layers.
[0013] The present disclosure also provides a method for forming a cylindrical capacitor. The method includes the following operations: forming a first electrode. Forming the first electrode includes forming a plurality of first electrode material layers and a first hard layer stacked one upon another in the form of a plurality of hollow cylinders, wherein the first hard layer is disposed between the first electrode material layers; and performing an ozone treatment on the exposed cylindrical surface portions of the first electrode material layers to convert the exposed cylindrical surface portions into a plurality of oxidized surface portions, wherein the hardness of the first hard layer is greater than the hardness of the first electrode material layers and the oxidized surface portions. Forming a dielectric layer on the oxidized surface portions. Forming a second electrode on the dielectric layer.
[0014] In some embodiments, forming the first electrode material layer and the first hard layer stacked on each other in a hollow cylindrical shape includes forming the first electrode material layer and the first hard layer on a cylindrical substrate, and the method further includes removing the cylindrical substrate before performing the ozone treatment.
[0015] In some embodiments, before the ozone treatment, a ratio of the thickness of the first hard layer to the total thickness of the first electrode material layers is 0.02 to 0.3.
[0016] In some embodiments, the ozone treatment is performed at a temperature of 220°C to 270°C.
[0017] In some embodiments, the ozone treatment is performed at a temperature of 220°C to 245°C.
[0018] In some embodiments, the ozone treatment is performed by using ozone, and the density of the ozone is 200 g / m 3 Up to 300g / m 3 .
[0019] In some embodiments, after performing the ozone treatment, the thickness of each of these oxidized surface portions is to
[0020] In some embodiments, after forming the first electrode, the first electrode has a hollow cylindrical shape, and multiple distances between the first hard layer and multiple cylindrical surfaces of the hollow cylinder of the first electrode are 0.4 to 0.6 times the thickness of the first electrode.
[0021] In some embodiments, forming the second electrode includes forming multiple second electrode material layers and a second hard layer stacked on the dielectric layer, wherein the second hard layer is arranged between these second electrode material layers, and the hardness of the second hard layer is greater than the hardness of multiple second electrode material layers.
[0022] In some embodiments, the method further includes oxidizing the exposed portion of the second electrode material layer after forming the second electrode material layer and the second hard layer. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The present disclosure can be more fully understood by reading the following detailed description of the embodiments and by referring to the following drawings.
[0024] Figure 1A is an isometric view of a cylindrical capacitor according to some embodiments of the present disclosure.
[0025] Figure 1B is a cross-sectional view of a cylindrical capacitor according to some embodiments of the present disclosure.
[0026] Figure 2 is a flow chart of a method of forming a cylindrical capacitor according to some embodiments of the present disclosure.
[0027] Figures 3 to 9 is a cross-sectional view of a structure during formation of a cylindrical capacitor by the method of the present disclosure according to some embodiments of the present disclosure. DETAILED DESCRIPTION
[0028] To provide a detailed and complete description of the present disclosure, various aspects of the embodiments are described below. This does not limit the embodiments of the present disclosure to a single form. The embodiments of the present disclosure may be combined or substituted with each other where beneficial, and other embodiments may be added without further description.
[0029] In addition, spatially relative terms, such as above and below, may be used to describe the relationship of one element (or feature) to another element (or feature) in the figures. Spatially relative terms are intended to encompass different orientations of the device when in use or operation, in addition to the orientation depicted in the figures. For example, the device may be oriented in other ways (e.g., rotated 90 degrees), and spatially relative terms may be interpreted accordingly. In this disclosure, unless otherwise indicated, the same element numbers in different figures refer to the same or similar elements formed from the same or similar materials by the same or similar methods.
[0030] The terms "approximately," "about," "substantially," "substantially," and the like used in this disclosure include values (or features) and deviations of the values (or features) as understood by those skilled in the art. For example, these terms may indicate values within one or more standard deviations (e.g., values within ±30%, ±20%, ±15%, ±10%, or ±5%), or may indicate deviations that include practical operations (e.g., "substantially parallel" may mean close to parallel in practice rather than perfectly parallel in ideal). In addition, an acceptable range of deviations may be selected based on the nature of the measurement or other properties, rather than applying one range of deviations to all values (or features).
[0031] The present disclosure provides a cylindrical capacitor 100, such as Figure 1A and Figure 1B As shown, Figure 1B yes Figure 1A Cross-sectional view taken along line AA. Cylindrical capacitor 100 includes a first electrode 101, a dielectric layer 102, and a second electrode 103. First electrode 101 has a hollow cylindrical shape and includes multiple oxidized surface portions 104, multiple first metal-containing layers 105, and a first hard layer 106. Oxidized surface portions 104 are located on multiple cylindrical surfaces 107 of the hollow cylinder of first electrode 101. First metal-containing layers 105 are located between oxidized surface portions 104. First hard layer 106 is located between first metal-containing layers 105, and the hardness of first hard layer 106 is greater than the hardness of oxidized surface portions 104 and first metal-containing layers 105. Dielectric layer 102 is disposed on first electrode 101. Second electrode 103 is disposed on dielectric layer 102. Next, cylindrical capacitor 100 will be described in detail using the following embodiments.
[0032] First electrode 101 has a hollow cylindrical shape and can be referred to as the lower electrode of cylindrical capacitor 100. First electrode 101 includes an oxidized surface portion 104 having a hollow cylindrical shape, a first metal-containing layer 105, and a first hard layer 106. Oxidized surface portion 104 reduces leakage of cylindrical capacitor 100. First metal-containing layer 105 is the primary conductive portion of first electrode 101 and comprises the remaining portion of first electrode 101 excluding oxidized surface portion 104 and first hard layer 106. First hard layer 106 increases the hardness of cylindrical capacitor 100, thereby compensating for the hardness loss of cylindrical capacitor 100 due to the inclusion of oxidized surface portion 104. By including first hard layer 106, the thickness T1 of each oxidized surface portion 104 can be within a desired range, so that the thickness is neither too small to cause leakage in cylindrical capacitor 100 nor too large to cause structural collapse of cylindrical capacitor 100. Specifically, when the hardness mismatch between the oxidized surface portion 104 and the first metal-containing layer 105 is too great, structural collapse may occur. In addition to reducing leakage and increasing the hardness of the structure, the inclusion of the first hard layer 106 allows the oxidized surface portion 104 to have a greater thickness T1, allowing it to be formed at a higher temperature during the subsequent ozone treatment. When the thickness T1 of each of the oxidized surface portions 104 is formed at a higher temperature, the capacitance value of the cylindrical capacitor 100 can also be increased. Next, the oxidized surface portion 104, the first metal-containing layer 105, and the first hard layer 106 will be described in detail through the following embodiments.
[0033] The oxidized surface portions 104 are multiple oxidized portions of the first electrode 101 at the cylindrical surface 107 of the hollow cylinder of the first electrode 101. The oxidized surface portions 104 prevent oxygen atoms of the dielectric layer 102 from migrating from the dielectric layer 102 to the first metal-containing layer 105. Once the oxygen atoms leave the vacancies originally occupied in the dielectric layer 102, the cylindrical capacitor 100 will leak. In some embodiments, the oxidized surface portions 104 are in direct contact with the dielectric layer 102, and the first metal-containing layer 105 and the first hard layer 106 are separated from the dielectric layer 102 by the oxidized surface portions 104. In some embodiments, the oxidized surface portions 104 include an inner oxidized surface portion 104A located at the cylindrical surface 107A on the inner side of the cylindrical surface 107 and an outer oxidized surface portion 104B located at the cylindrical surface 107B on the outer side of the cylindrical surface 107. In some embodiments, the thickness T1 of each of the oxidized surface portions 104 is preferably about 10 ... to (ie, the thickness T1 of the inner oxidized surface portion 104A and the thickness T1 of the outer oxidized surface portion 104B are preferably to ),For example or In some embodiments, the oxidized surface portion 104 preferably includes titanium oxynitride, titanium oxide, titanium silicon oxynitride, or a combination thereof.
[0034] The first metal-containing layer 105 is located between the oxidized surface portions 104 and is covered by the oxidized surface portions 104. In some embodiments, the first metal-containing layer 105 includes an inner first metal-containing layer 105A in direct contact with the inner oxidized surface portion 104A and an outer first metal-containing layer 105B in direct contact with the outer oxidized surface portion 104B. In embodiments where the first hard layer 106 includes multiple sublayers, the first metal-containing layer 105 may further include a middle first metal-containing layer 105C located between the sublayers, such that the sublayers are separated from each other by the middle first metal-containing layer 105C. For example, in Figure 1B In the embodiment, the first hard layer 106 comprises three sublayers, including a first sublayer 106a, a second sublayer 106b, and a third sublayer 106c, separated by two intermediate first metal-containing layers. In some embodiments, the first metal-containing layer 105 preferably comprises titanium nitride, titanium silicon nitride, or a combination thereof.
[0035] The first hard layer 106 is disposed between and covered by the first metal-containing layers 105. The first hard layer 106 is a doped region of the first electrode 101, and the material of the first hard layer 106 is different from the material of the first metal-containing layer 105. In other words, a physical interface exists between the first hard layer 106 and the first metal-containing layer 105. The material of the first hard layer 106 increases the hardness of the cylindrical capacitor 100. In some embodiments, the hardness of the first hard layer 106 is greater than the hardness of the first metal-containing layers 105 and the oxidized surface portions 104. In some embodiments, the hardness of the first hard layer 106 is 9 GPa to 13 GPa, the hardness of each of the first metal-containing layers 105 is 8.5 GPa to 12.5 GPa, and the hardness of each of the oxidized surface portions is 0.35 GPa to 0.75 GPa. In some embodiments, the first hard layer 106 preferably comprises a silicon layer, a carbon layer, an aluminum layer, or a combination thereof. In some embodiments, the first hard layer 106 is electrically conductive.
[0036] In some embodiments, first hard layer 106 may include multiple sub-layers, and the description of first hard layer 106 provided above (e.g., hardness range, material, etc.) applies to each sub-layer. In some embodiments, the number of sub-layers is any integer in the range of 1 to 12 to finely control the hardness of cylindrical capacitor 100. In some embodiments, the number of sub-layers is any integer in the range of 1 to 6 to more efficiently control the hardness of cylindrical capacitor 100. In some embodiments, the sub-layers are separated from each other.
[0037] In some embodiments, the thickness T2 of each sub-layer of the first hard layer 106 is preferably to For example or In some embodiments, the ratio of the thickness of the first hard layer 106 (or the total thickness of the sub-layers) to the total thickness of the oxidized surface portion 104 and the first metal-containing layer 105 is preferably 0.02 to 0.3, for example, 0.02, 0.04, 0.06, 0.08, 0.1, 0.15, 0.2, 0.25 or 0.3, so as to provide the cylindrical capacitor 100 with sufficient hardness and prevent the first hard layer 106 from occupying too much of the first electrode 101 and affecting the functions of the oxidized surface portion 104 and the first metal-containing layer 105.
[0038] In some embodiments, the first hard layer 106 is separated from the oxidized surface portion 104 by the first metal-containing layer 105 to prevent the first hard layer 106 from being oxidized and losing its hardness. In some embodiments, the distance D1 between the first hard layer 106 (or each sub-layer) and the cylindrical surface 107 of the hollow cylinder of the first electrode 101 is preferably 0.4 to 0.6 times, for example, 0.4 times, 0.45 times, 0.5 times, 0.55 times, or 0.6 times, the thickness T3 of the first electrode 101. For example, in Figure 1B In the embodiment, the distance D1 between the first sublayer 106a and the inner cylindrical surface 107A is 0.4 times the thickness T3 of the first electrode 101, and the distance D1 between the first sublayer 106a and the outer cylindrical surface 107B is 0.55 times the thickness T3 of the first electrode 101. In some embodiments, the thickness T3 of the first electrode 101 is preferably to For example or
[0039] Dielectric layer 102 is disposed on first electrode 101. Dielectric layer 102 is disposed between first electrode 101 and second electrode 103 to store charge and increase the capacitance of cylindrical capacitor 100. In some embodiments, dielectric layer 102 includes inner dielectric layer 102A disposed in a hollow cylindrical shape on inner oxidized surface portion 104A and outer dielectric layer 102B disposed in a hollow cylindrical shape on outer oxidized surface portion 104B. In some embodiments, dielectric layer 102 includes, but is not limited to, hafnium zirconium oxide, zirconium oxide, hafnium oxide, aluminum oxide, rhodium oxide, ruthenium oxide, or combinations thereof.
[0040] The second electrode 103 is disposed on the dielectric layer 102 and can be referred to as the top electrode of the cylindrical capacitor 100. In some embodiments, the second electrode 103 includes an inner second electrode 103A having a cylindrical shape disposed on the inner dielectric layer 102A and an outer second electrode 103B having a hollow cylindrical shape disposed on the outer dielectric layer 102B. In some embodiments, the second electrode 103 includes a plurality of second metal-containing layers 108. In some embodiments, the second metal-containing layers 108 include a plurality of inner second metal-containing layers 108A in the inner second electrode 103A and a plurality of outer second metal-containing layers 108B in the outer second electrode 103B. In some embodiments, the second metal-containing layers 108 preferably include titanium nitride, titanium silicon nitride, or a combination thereof. In some embodiments, the second electrode 103 may further include a second hard layer 109 disposed between the second metal-containing layers 108 to increase the hardness of the cylindrical capacitor 100. In some embodiments, the second hard layer 109 includes an inner second hard layer 109A disposed in a hollow cylindrical shape between the inner second metal-containing layers 108A, and an outer second hard layer 109B disposed in a hollow cylindrical shape between the outer second metal-containing layers 108B. The second hard layer 109 serves as a doped region of the second electrode 103, and the material of the second hard layer 109 is different from that of the second metal-containing layer 108. In other words, a physical interface exists between the second hard layer 109 and the second metal-containing layer 108. In some embodiments, the hardness of the second hard layer 109 is greater than that of the second metal-containing layer 108. In some embodiments, the hardness of the second hard layer 109 is between 9 GPa and 13 GPa, and the hardness of each of the second metal-containing layers 108 is between 8.5 GPa and 12.5 GPa. In some embodiments, the second hard layer 109 preferably comprises a silicon layer, a carbon layer, an aluminum layer, or a combination thereof. In some embodiments, the second hard layer 109 is electrically conductive. In some embodiments, the second electrode 103 may further include an outer oxidized surface portion 110 having a hollow cylindrical shape at the outer cylindrical surface 111B of the hollow cylinder of the outer second electrode 103B, thereby improving the quality of the cylindrical capacitor 100. In some embodiments, the outer oxidized surface portion 110 preferably includes titanium oxynitride, titanium oxide, titanium silicon oxynitride, or a combination thereof.
[0041] In some embodiments, although not shown in the figures, the inner second hard layer 109A may include multiple sub-layers, the outer second hard layer 109B may include multiple sub-layers, and the description of the second hard layer 109 provided above (e.g., hardness range, material, etc.) applies to each sub-layer in the inner second hard layer 109A and the outer second hard layer 109B. In some embodiments, the number of sub-layers in the inner second hard layer 109A (or the number of sub-layers in the outer second hard layer 109B) is any integer in the range of 1 to 12, so that the hardness of the cylindrical capacitor 100 can be finely controlled. In some embodiments, the number of sub-layers in the inner second hard layer 109A (or the number of sub-layers in the outer second hard layer 109B) is any integer in the range of 1 to 6, so that the hardness of the cylindrical capacitor 100 can be more efficiently controlled. In some embodiments, although not shown in the figures, these sub-layers are separated from each other. On the contrary, Figure 1B The embodiment only illustrates the inner second hard layer 109A as a sub-layer and the outer second hard layer 109B as a sub-layer. In some embodiments, the thickness T4 of each sub-layer in the inner second hard layer 109A is preferably to For example or In some embodiments, the thickness T5 of each sub-layer in the outer second hard layer 109B is preferably to For example or
[0042] In some embodiments, the ratio of the thickness of the outer second hard layer 109B (or the total thickness of the sublayers of the outer second hard layer 109B) to the total thickness of the outer oxidized surface portion 110 and the outer second metal-containing layer 108B is preferably 0.02 to 0.3, for example, 0.02, 0.04, 0.06, 0.08, 0.1, 0.15, 0.2, 0.25 or 0.3, so as to provide a cylindrical capacitor 100 with sufficient hardness and prevent the outer second hard layer 109B from occupying too much of the outer second electrode 103B and affecting the functions of the outer oxidized surface portion 110 and the outer second metal-containing layer 108B.
[0043] In some embodiments, the outer second hard layer 109B is separated from the outer oxidized surface portion 110 by the outer second metal-containing layer 108B to prevent the outer second hard layer 109B from being oxidized and losing hardness. In some embodiments, the distance D2 between the outer second hard layer 109B (or each sublayer in the outer second hard layer 109B) and the multiple cylindrical surfaces 111 (including the inner cylindrical surface 111A and the outer cylindrical surface 111B) of the hollow cylinder of the outer second electrode 103B is 0.4 to 0.6 times, for example, 0.4 times, 0.45 times, 0.5 times, 0.55 times, or 0.6 times the thickness T6 of the outer second electrode 103B. In some embodiments, the thickness T6 of the outer second electrode 103B is preferably to For example or
[0044] The present disclosure also provides a method 200 for forming the cylindrical capacitor 100. The method 200 includes: Figure 2 The operation shown is as follows. The first electrode 101 is formed, and the formation of the first electrode 101 includes forming a plurality of first electrode material layers 113 and a first hard layer 106 stacked in a hollow cylindrical shape, wherein the first hard layer 106 is disposed between the first electrode material layers 113; and performing an ozone treatment on the plurality of exposed cylindrical surface portions 114 of the first electrode material layers 113 to convert the exposed cylindrical surface portions 114 into oxidized surface portions 104, wherein the hardness of the first hard layer 106 is greater than the hardness of the first electrode material layers 113 and the oxidized surface portions 104. A dielectric layer 102 is formed on the oxidized surface portions 104. A second electrode 103 is formed on the dielectric layer 102. Next, the method 200 is described in detail through the following embodiments.
[0045] In operation 201 (see Figures 3 to 6), forming the first electrode 101. Forming the first electrode 101 includes alternately forming first electrode material layers 113 and first hard layers 106, such that the first electrode material layers 113 and the first hard layers 106 are stacked on each other. The first electrode material layer 113 is substantially the same as the first metal-containing layer 105 described above, except that multiple portions of the first electrode material layer 113 (e.g., the exposed cylindrical surface portion 114 described below) will be converted into oxidized surface portions 104 in the following operations. In some embodiments, forming the first electrode material layer 113 and the first hard layer 106 includes forming the first electrode material layer 113 and the first hard layer 106 on a cylindrical substrate 115, such that the first electrode material layer 113 and the first hard layer 106 can be formed into a hollow cylindrical shape. In some embodiments, each of the first electrode material layer 113 and the first hard layer 106 is conformally formed on the cylindrical substrate 115. In some embodiments, forming the first electrode material layer 113 and the first hard layer 106 includes any suitable deposition method, such as atomic layer deposition (ALD). In some embodiments, before performing the ozone treatment described below, the ratio of the thickness of the first hard layer 106 (or the total thickness of each sub-layer of the first hard layer 106 described above) to the total thickness of the first electrode material layer 113 is 0.02 to 0.3, such as 0.02, 0.04, 0.06, 0.08, 0.1, 0.15, 0.2, 0.25, or 0.3. In some embodiments, the method 200 further includes removing the cylindrical substrate 115 before performing the ozone treatment. In some embodiments, removing the cylindrical substrate 115 includes any suitable etching method, such as wet etching or dry etching.
[0046] Next, in some embodiments, ozone treatment is performed on the exposed cylindrical surface portion 114 of the first electrode material layer 113 (at Figure 5 ) in the region indicated by the dashed line in FIG, to convert the exposed cylindrical surface portion 114 into an oxidized surface portion 104. After performing the ozone treatment, the first electrode 101 described above is formed, for example Figure 1B The first electrode 101 is formed in the embodiment described above. The detailed embodiment of the first electrode 101 can be referred to above. In some embodiments, the ozone treatment is performed by using ozone, and the density of ozone is preferably 200g / m 3 Up to 300g / m 3 , for example 200g / m 3 , 250g / m 3 or 300g / m 3, so as to effectively form the desired thickness T1 of the oxidized surface portion 104. In some embodiments, the ozone treatment is preferably performed at a temperature of 220°C to 270°C, such as 220°C, 230°C, 240°C, 250°C, 260°C, or 270°C, so as to effectively form the desired thickness T1 of the oxidized surface portion 104. The aforementioned temperature range can also improve the crystallinity of the dielectric layer 102 formed in the following operation, so that the capacitance value of the cylindrical capacitor 100 can be increased. In some embodiments, the ozone treatment is more preferably performed at a temperature of 220°C to 245°C, such as 220°C, 225°C, 230°C, 235°C, 240°C, or 245°C, so that the capacitance value of the cylindrical capacitor 100 is sufficiently satisfactory and the thickness T1 of the oxidized surface portion 104 is not too thick to reduce the hardness of the cylindrical capacitor 100.
[0047] In operation 202 (see Figure 7 ), forming the dielectric layer 102 on the oxidized surface portion 104 of the first electrode 101. In some embodiments, the dielectric layer 102 is conformally formed on a plurality of cylindrical surfaces of the hollow cylinder of the first electrode 101. In some embodiments, forming the dielectric layer 102 comprises any suitable deposition method, such as atomic layer deposition (ALD). After operation 202, the dielectric layer 102 described above is formed, for example Figure 1B The dielectric layer 102 described in the embodiment is formed. The detailed embodiment of the dielectric layer 102 can be referred to above.
[0048] In operation 203 (see Figures 8 and 9 ), forming the second electrode 103 on the dielectric layer 102. In some embodiments, forming the second electrode 103 includes alternately forming a second electrode material layer 116 and a second hard layer 109 on the dielectric layer 102. The second electrode material layer 116 is substantially the same as the second metal-containing layer 108 described above, except that a portion of the second electrode material layer 116 (e.g., the exposed cylindrical surface portion 117 described below) will be converted into an outer oxidized surface portion 110 in the following operation. In some embodiments, the second electrode material layer 116 and the second hard layer 109 are conformally formed on the dielectric layer 102. In some embodiments, forming the second electrode material layer 116 and the second hard layer 109 includes any suitable deposition method, such as atomic layer deposition (ALD). In some embodiments, forming the second electrode 103 may also include oxidizing the exposed cylindrical surface portion 117 of the second electrode material layer 116 (at the end of the exposed cylindrical surface portion 117) after forming the second electrode material layer 116 and the second hard layer 109. Figure 9) to convert the exposed cylindrical surface portion 117 into the outer oxidized surface portion 110. Thus, after the above-mentioned operation, the cylindrical capacitor 100 including the second electrode 103 described above is formed, for example Figure 1B The cylindrical capacitor 100 described in the embodiment is formed. The detailed embodiment of the second electrode 103 can be referred to above.
[0049] Some detailed examples are provided below, including Example 1, Example 2 and Example 3. It should be noted that the detailed examples are provided for a better understanding of the present disclosure and are not intended to limit the present disclosure. The first electrode 101, the dielectric layer 102 and the second electrode 103 of the cylindrical capacitor 100 formed in Example 1, Example 2 and Example 3 are substantially the same, except that the thickness T1 of the oxidized surface portion 104 in the first electrode 101 and the temperature used in the ozone treatment are different, so the performance (e.g., capacitance value) of the resulting cylindrical capacitor 100 may be different. The results are summarized in Table 1 below. Table 1 provides the temperature used in the ozone treatment and the thickness T1 formed by the oxidized surface portion 104 in the first electrode 101. The capacitance value of each cylindrical capacitor 100 measured in Example 1, Example 2 and Example 3 is satisfactory, as shown in Table 1. However, the error rate of the cylindrical capacitor 100 increases with the increase of the thickness T1. The error rate is obtained by measuring the probability of the cylindrical capacitor 100 collapsing due to weak hardness. To better understand the comparison of Example 1, Example 2, and Example 3, the error rates are shown in Table 1 as relative error rates relative to the error rates found in Example 3.
[0050] Table 1
[0051]
[0052] The cylindrical capacitor and the method for forming the same provided by the present disclosure reduce leakage of the cylindrical capacitor, avoid structural collapse of the cylindrical capacitor, and increase the capacitance value of the cylindrical capacitor by improving the hardness of the cylindrical capacitor.
[0053] This disclosure describes some embodiments in considerable detail, but other embodiments are also possible. Therefore, the description of the embodiments in this disclosure is not intended to limit the scope and spirit of the appended claims. Those skilled in the art may make modifications and variations to this disclosure without departing from the scope and spirit of this disclosure. This disclosure is intended to cover such modifications and variations as long as they fall within the scope and spirit of the appended claims.
[0054]
Explanation of symbols
[0055] AA: Line
[0056] 100: Cylindrical capacitor
[0057] 101: First electrode
[0058] 102: Dielectric layer
[0059] 102A: Inner dielectric layer
[0060] 102B: External dielectric layer
[0061] 103: Second electrode
[0062] 103A: Internal second electrode
[0063] 103B: External second electrode
[0064] 104: Oxidized surface part
[0065] 104A: Internal oxidized surface
[0066] 104B: External oxidized surface
[0067] 105: First metal-containing layer
[0068] 105A: The first inner metal-containing layer
[0069] 105B: Outer first metal-containing layer
[0070] 105C: The first metal-containing layer in the middle
[0071] 106: First hard layer
[0072] 106a: First sublayer
[0073] 106b: Second sublayer
[0074] 106c: Third sublayer
[0075] 107: Cylindrical surface
[0076] 107A: Internal cylindrical surface
[0077] 107B: External cylindrical surface
[0078] 108: Second metal-containing layer
[0079] 108A: The second inner metal-containing layer
[0080] 108B: Outer second metal-containing layer
[0081] 109: Second hard layer
[0082] 109A: The second hard layer inside
[0083] 109B: Second hard layer on the outside
[0084] 110: External oxidized surface
[0085] 111: Cylindrical surface
[0086] 111A: Internal cylindrical surface
[0087] 111B: External cylindrical surface
[0088] 113: First electrode material layer
[0089] 114: Exposed cylindrical surface portion
[0090] 115: Cylindrical substrate
[0091] 116: Second electrode material layer
[0092] 117: Exposed cylindrical surface portion
[0093] 200: Method
[0094] 201: Operation
[0095] 202: Operation
[0096] 203: Operation
[0097] D1: Distance
[0098] D2: Distance
[0099] T1: thickness
[0100] T2: Thickness
[0101] T3: Thickness
[0102] T4: Thickness
[0103] T5: Thickness
[0104] T6: Thickness.
Claims
1. A cylindrical capacitor, characterized in that: include: The first electrode has a hollow cylindrical shape, wherein the first electrode comprises: a plurality of oxidized surface portions at a plurality of cylindrical surfaces of the hollow cylinder of the first electrode; a plurality of first metal-containing layers between the plurality of oxidized surface portions; and a first hard layer disposed between the plurality of first metal-containing layers, and a hardness of the first hard layer being greater than a plurality of hardnesses of the plurality of oxidized surface portions and the plurality of first metal-containing layers; A dielectric layer is disposed on the first electrode; and The second electrode is disposed on the dielectric layer. 2 . The cylindrical capacitor of claim 1 , wherein the first hard layer comprises a silicon layer, a carbon layer, an aluminum layer, or a combination thereof.
3. The cylindrical capacitor of claim 1, wherein the plurality of first metal-containing layers comprises titanium nitride, titanium silicon nitride, or a combination thereof, and the plurality of oxidized surface portions comprises titanium oxynitride, titanium oxide, titanium silicon oxynitride, or a combination thereof. 4 . The cylindrical capacitor according to claim 1 , wherein a plurality of distances between the first hard layer and the plurality of cylindrical surfaces of the hollow cylinder of the first electrode are 0.4 to 0.6 times the thickness of the first electrode.
5. The cylindrical capacitor according to claim 4, wherein the thickness of the first electrode is to 6 . The cylindrical capacitor of claim 1 , wherein a ratio of a thickness of the first hard layer to a total thickness of the plurality of oxidized surface portions to the plurality of first metal-containing layers is in a range of 0.02 to 0.
3.
7. The cylindrical capacitor of claim 1 wherein the first hard layer is separated from the plurality of oxidized surface portions by the plurality of first metal-containing layers.
8. The cylindrical capacitor of claim 1, wherein the plurality of oxidized surface portions are in direct contact with the dielectric layer, and the plurality of first metal-containing layers and the first hard layer are separated from the dielectric layer by the plurality of oxidized surface portions.
9. The cylindrical capacitor of claim 1 , wherein the thickness of each of the plurality of oxidized surface portions is to 10. The cylindrical capacitor of claim 1, wherein the second electrode comprises a plurality of second metal-containing layers and a second hard layer between the plurality of second metal-containing layers, and a hardness of the second hard layer is greater than hardnesses of the plurality of second metal-containing layers.
11. A method for forming a cylindrical capacitor, characterized in that: include: forming a first electrode, comprising: forming a plurality of first electrode material layers and a first hard layer stacked one on another in the shape of a plurality of hollow cylinders, wherein the first hard layer is disposed between the plurality of first electrode material layers; and performing an ozone treatment on the plurality of exposed cylindrical surface portions of the plurality of first electrode material layers to convert the plurality of exposed cylindrical surface portions into a plurality of oxidized surface portions, wherein a hardness of the first hard layer is greater than a plurality of hardnesses of the plurality of first electrode material layers and the plurality of oxidized surface portions; forming a dielectric layer on the plurality of oxidized surface portions; and A second electrode is formed on the dielectric layer.
12. The method according to claim 11, wherein forming the plurality of first electrode material layers and the first hard layer stacked on each other in the shape of the plurality of hollow cylinders includes forming the plurality of first electrode material layers and the first hard layer on a cylindrical substrate, and the method further includes removing the cylindrical substrate before performing the ozone treatment. 13 . The method according to claim 11 , wherein before the ozone treatment is performed, a ratio of a thickness of the first hard layer to a total thickness of the plurality of first electrode material layers is 0.02 to 0.
3. The method according to claim 11 , wherein the ozone treatment is performed at a temperature of 220° C. to 270° C.
15. The method according to claim 14, wherein the ozone treatment is performed at the temperature of 220°C to 245°C.
16. The method according to claim 11, wherein the ozone treatment is performed by using ozone, and the density of the ozone is 200 g / m 3 Up to 300g / m 3 .
17. The method of claim 11, wherein after performing the ozone treatment, the thickness of each of the plurality of oxidized surface portions is to 18. The method according to claim 11, wherein after forming the first electrode, the first electrode has a shape of a hollow cylinder, and multiple distances between the first hard layer and multiple cylindrical surfaces of the hollow cylinder of the first electrode are 0.4 times to 0.6 times the thickness of the first electrode.
19. The method according to claim 11, wherein forming the second electrode includes forming a plurality of second electrode material layers and a second hard layer stacked on the dielectric layer, wherein the second hard layer is arranged between the plurality of second electrode material layers, and the hardness of the second hard layer is greater than the plurality of hardnesses of the plurality of second electrode material layers. 20 . The method according to claim 19 , further comprising oxidizing exposed portions of the plurality of second electrode material layers after forming the plurality of second electrode material layers and the second hard layer.