This application claims the priority of Chinese Patent Application No. 202111514833.6 submitted to the Chinese Intellectual Property Office on Dec. 13, 2021, the disclosure of which is incorporated herein in its entirety by reference.
The present disclosure relates to the technical field of semiconductors, and in particular to a method of manufacturing a semiconductor structure and a semiconductor structure.
With the increase in integration degree of semiconductor structures, capacitor structures are developed toward high aspect ratios and high densities. During manufacture of the capacitor structures, there are different etching rates for regions of different densities. In case of a high aspect ratio of the capacitor structure, manufacturing progresses may be varied for regions of different densities, and some regions are etched insufficiently, while other regions are etched excessively, thus affecting the product yield.
An overview of the subject matter detailed in the present disclosure is provided below, which is not intended to limit the protection scope of the claims.
The present disclosure provides a method of manufacturing a semiconductor structure and a semiconductor structure.
An aspect of the present disclosure provides a method of manufacturing a semiconductor structure, including: forming a first stacked structure, and forming a first target structure in the first stacked structure; and forming a second stacked structure on the first stacked structure, and forming a second target structure in contact with the first target structure in the second stacked structure.
Another aspect of the present disclosure provides a semiconductor structure, including:
a bottom electrode, including a first target structure and a second target structure stacked on the first target structure; and
a support structure, including an intermediate support layer covering a part of a seam of a connecting surface of the first target structure and the second target structure.
Other aspects of the present disclosure are understandable upon reading and understanding of the drawings and detailed description.
The drawings incorporated into the specification and constituting part of the specification illustrate the embodiments of the present disclosure, and are used together with the description to explain the principles of the embodiments of the present disclosure. In these drawings, similar reference numerals are used to represent similar elements. The drawings in the following description are part rather than all of the embodiments of the present disclosure. Those skilled in the art may derive other drawings based on these drawings without creative efforts.
01. dense region, 02. non-dense region, 10. first stacked structure, 11. first sacrificial layer, 12. first support layer, 100. bottom electrode, 101. first target pattern hole, 110. first target structure, 111. first conductive layer, 120. second target structure, 121. second conductive layer, 20. second stacked structure, 21. second support layer, 22. dielectric layer, 200. support structure, 201. second target pattern hole, 210. support unit, 221. second sacrificial layer, 222. third sacrificial layer, 30. substrate, 300. upper support layer, 31. isolation layer, 40. capacitor contact portion, 400. dielectric layer, 50. first buffer layer, 51. first target pattern, 500. top electrode layer, 60. patterned layer, 70. second buffer layer, 71. second target pattern, 80. first mask layer, and 81. first pattern.
To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the following clearly and completely describes the technical solutions in the embodiments of the present disclosure with reference to the accompanying drawings in the embodiments of the present disclosure. Apparently, the described embodiments are some but not all of the embodiments of the present disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without creative efforts should fall within the protection scope of the present disclosure. It should be noted that the embodiments in the present disclosure and features in the embodiments may be combined with each other in a non-conflicting manner.
An exemplary embodiment of the present disclosure provides a method of manufacturing a semiconductor structure.
There are no limits made on the semiconductor structure in the embodiment. The semiconductor structure is described below by taking a dynamic random access memory (DRAM) as an example, but the embodiment is not limited thereto. The semiconductor structure in the embodiment may also be other structures.
As shown in
Step S110: Form a first stacked structure, and form a first target structure in the first stacked structure.
In the embodiment, as shown in
As shown in
Step S120: Form a second stacked structure on the first stacked structure, and form a second target structure in contact with the first target structure in the second stacked structure.
As shown in
The manufacturing method in the embodiment separates the manufacture of the target structure into the manufacture of the first target structure and the manufacture of the second target structure, thereby reducing the depth in each manufacture and minimizing the influence of a high aspect ratio on the manufacture.
Descriptions will be made to the implementation of Step S110 in an exemplary embodiment. During implementation, as shown in
Step S111: Sequentially form a first sacrificial layer and a first support layer.
As shown in
The first sacrificial layer 11 is made of a material including silicon oxide or boro-phospho-silicate glass (BPSG). The material of the first sacrificial layer 11 may be doped with boron or phosphorus. The first support layer 12 is made of a material including any one or a combination of silicon nitride, silicon oxynitride, or silicon carbonitride.
Step S112: Pattern the first sacrificial layer and the first support layer, and form a first target pattern hole in the first stacked structure.
As shown in
In the embodiment, the first target pattern 51 is formed according to a distribution density of the capacitor contact portion 40 in the substrate 30. The first target pattern 51 is distributed in a dense region 01 and a non-dense region 02. As shown in
In the embodiment, as shown in
Step S113: Form the first target structure in the first target pattern hole.
As shown in
As shown in
By shortening the time for forming the first target pattern hole, the top surface of the first stacked structure is still protected by the first buffer layer after the first target pattern hole is formed. The method in the embodiment prevents the etching damage to the top of the first target pattern hole in the dense region due to the greater etching rate of the dense region than that of the non-dense region, and ensures the highly accurate size of the first target structure.
Descriptions will be made to the implementation of Step S120 in an exemplary embodiment. During implementation, as shown in
Step S121: Sequentially form a second support layer and a dielectric layer on the first stacked structure.
As shown in
The second support layer 21 is made of a material including any one or a combination of silicon nitride, silicon oxynitride, or silicon carbonitride.
In the embodiment, as shown in
Both the third sacrificial layer 222 and the second sacrificial layer 221 are made of a material with an etch selectivity. Exemplarily, the second sacrificial layer 221 may be made of a material including silicon oxide or BPSG. The material of the second sacrificial layer 222 may be doped with boron or phosphorus. The third sacrificial layer may be made of a material including any one or a combination of silicon nitride, silicon oxynitride, or silicon carbonitride.
Step S122: Pattern the second support layer and the dielectric layer, and form a second target pattern hole in the second stacked structure, the second target pattern hole at least exposing a part of the first target structure.
As shown in
In the embodiment, the second target pattern holes 201 are arranged in a same manner as the first target pattern holes 101. The second target pattern holes 201 are partially formed in the dense region 01, and partially formed in the non-dense region 02.
Likewise, referring to
Step S123: Form the second target structure in the second target pattern hole.
As shown in
As shown in
The embodiment reduces the depth in each manufacture to ensure the yield of the first target structure and the second target structure, thereby improving the yield of the final semiconductor structure.
As shown in
Step S210: Form a first stacked structure, and form a first target structure in the first stacked structure.
Step S220: Form a second stacked structure on the first stacked structure, and form a second target structure in contact with the first target structure in the second stacked structure.
Step S230: Remove a part of the second stacked structure and a part of the first stacked structure, a remaining part of the second stacked structure and a remaining part of the first stacked structure forming a support structure.
Steps S210-S220 in the embodiment are implemented in a same manner as Steps S110-S220 of the foregoing embodiment, and will not be repeated herein.
In the embodiment, as shown in
Step S231: Form a first mask layer, the first mask layer covering a part of a top surface of the second stacked structure and a part of a top surface of the second target structure.
As shown in
Step S232: Sequentially remove a part of the third sacrificial layer, the second sacrificial layer and a part of the second support layer of the second stacked structure based on the first mask layer.
As shown in
Step S233: Sequentially remove a part of the first support layer and the first sacrificial layer of the first stacked structure based on the first mask layer.
As shown in
As shown in
In the embodiment, a remaining part of the third sacrificial layer 222 forms an upper support layer 300. The upper support layer 300 is provided on a top of the second target structure 120 and covers a part of a sidewall of the second target structure 120. The upper support layer 300 keeps the same shape as the support structure 200. The upper support layer 300 and the support structure 200 jointly support the target structure formed by the first target structure 110 and the second target structure 120. When the target structure is high, the upper support layer 300 can better support the target structure, thus ensuring the stability and the anti-tipping performance of the semiconductor structure.
According to the semiconductor structure in the embodiment, the support structure is provided at a junction of the first target structure and the second target structure to implement stable connection between the first target structure and the second target structure.
According to an exemplary embodiment, as shown in
According to the semiconductor structure in the embodiment, the first target structure and the second target structure are stacked to form the target structure. A plurality of the target structures serve as one group, and the plurality of the target structures in each group are connected into a whole through the support structure, such that the anti-tipping performance of the semiconductor structure and the stability of the semiconductor structure are improved.
In an embodiment, as shown in
The support structure formed based on the first mask layer in the embodiment includes three independent target structures. The three target structures in each group are connected into a whole through the support structure. Any two of the three target structures in each group are connected by a support unit. Therefore, the space occupied by the support structure in the semiconductor structure is reduced and the available space in the semiconductor is increased.
In the embodiment, the first mask layer exposes a larger area of the third sacrificial layer and the window for removing the third sacrificial layer exposed by the first mask layer is larger, such that the third sacrificial layer is removed more easily. Likewise, other parts of the second stacked structure and the first stacked structure are also removed more easily.
In other embodiments, as shown in
Step S234: Remove the remaining part of the third sacrificial layer.
In the embodiment, as shown in
As shown in
Step S310: Form a first stacked structure, and form a first target structure in the first stacked structure.
Step S320: Form a second stacked structure on the first stacked structure, and form a second target structure in contact with the first target structure in the second stacked structure.
Step S330: Remove a part of the second stacked structure and a part of the first stacked structure, a remaining part of the second stacked structure and a remaining part of the first stacked structure forming a support structure.
Steps S310-S330 of the embodiment are implemented in the same manner as Steps S210-S230 of the foregoing embodiment, and will not be repeated herein.
Step S340: Form a dielectric layer, the dielectric layer at least covering an exposed part of a sidewall of the first target structure, an exposed part of a sidewall of the second target structure and a top surface of the second target structure.
The dielectric layer 400 may be deposited with ALD. The dielectric layer 400 is made of a high-k material, which has a dielectric constant greater than that of silicon dioxide.
As shown in
In the embodiment, the high-k material may include a compound containing one or more of rare earth elements, Hf, Rh, Ba or Al. The high-k material can be hafnium (IV) oxide, titanium nitride, aluminium oxide, lanthanum oxide, etc.
Step S350: Form a top electrode layer, the top electrode layer covering the dielectric layer.
As shown in
In the embodiment, as shown in
The capacitor structure formed in the embodiment takes the superposed first target structure and second target structure as the bottom electrode. The bottom electrode is formed in two manufacturing steps, such that the first target structure and second target structure of the bottom electrode have the highly accurate sizes and the bottom electrode has the highly accurate size. Even if the capacitor structure having a high aspect ratio is formed, the capacitor structure can still keep the highly accurate size to achieve the better performance and higher yield of the semiconductor structure.
An exemplary embodiment of the present disclosure provides a semiconductor structure. As shown in
According to the semiconductor structure in the embodiment, along a stacked direction, the first target structure 110 may be a structure having a same size from the bottom up, the first target structure 110 may be a structure having a size gradually increased from the bottom up.
The second target structure 120 may be a structure having a same size from the bottom up, a structure having a size gradually increased from the bottom up.
As shown in
According to an exemplary embodiment, most contents are substantially the same as the foregoing embodiment. The difference between the embodiment and the foregoing embodiment lies in: A projection pattern of each of the support structures 200 on the substrate includes a plurality of arc-shaped structures with a same radian.
As shown in
In the embodiment, the support structures 200 each are connected to three bottom electrodes 100. The support structures 200 each include three support units 210 with a same radian. Through the three support units 210, the three bottom electrodes 100 are sequentially connected into a whole. Connecting lines between central points of the three bottom electrodes 100 form an inscribed triangle of a circle where projection of the support units 210 on the substrate 30 is located. The semiconductor structure in the embodiment achieves the best anti-tipping performance and highest overall stability.
According to an exemplary embodiment, as shown in
In the embodiment, the upper support layer 300 is provided on the top of the semiconductor structure. When the semiconductor structure has a high aspect ratio, the upper support layer 300 better supports the top of the semiconductor structure, thereby achieving the better stability and anti-tipping performance of the semiconductor structure.
According to an exemplary embodiment, as shown in
According to an exemplary embodiment, as shown in
According to the semiconductor structure in the embodiment, the bottom electrode 100 includes the first target structure 110 and the second target structure 120, such that the bottom electrode is formed more easily. The support structure 200 is provided at a junction of the first target structure 110 and the second target structure 120 to implement stable connection between the first target structure 110 and the second target structure 120.
The embodiments or implementations of this specification are described in a progressive manner, and each embodiment focuses on differences from other embodiments. The same or similar parts between the embodiments may refer to each other.
In the description of the specification, the description with reference to terms such as “an embodiment”, “an illustrative embodiment”, “some implementations”, “an illustrative implementation” and “an example” means that the specific feature, structure, material or feature described in combination with the implementation(s) or example(s) is included in at least one implementation or example of the present disclosure.
In this specification, the schematic expression of the above terms does not necessarily refer to the same embodiment or example. Moreover, the described specific feature, structure, material or characteristic may be combined in an appropriate manner in any one or more embodiments or examples.
It should be noted that in the description of the present disclosure, the terms such as “center”, “top”, “bottom”, “left”, “right”, “vertical”, “horizontal”, “inner” and “outer” indicate the orientation or position relationships based on the drawings. These terms are merely intended to facilitate description of the present disclosure and simplify the description, rather than to indicate or imply that the mentioned device or element must have a specific orientation and must be constructed and operated in a specific orientation. Therefore, these terms should not be construed as a limitation to the present disclosure.
It can be understood that the terms such as “first” and “second” used in the present disclosure can be used to describe various structures, but these structures are not limited by these terms. Instead, these terms are merely intended to distinguish one element from another.
The same elements in one or more drawings are denoted by similar reference numerals. For the sake of clarity, various parts in the drawings are not drawn to scale. In addition, some well-known parts may not be shown. For the sake of brevity, the structure obtained by implementing a plurality of steps may be shown in one figure. In order to make the understanding of the present disclosure more clearly, many specific details of the present disclosure, such as the structure, material, size, processing process and technology of the device, are described below. However, as those skilled in the art can understand, the present disclosure may not be implemented according to these specific details.
Finally, it should be noted that the above embodiments are merely intended to explain the technical solutions of the present disclosure, rather than to limit the present disclosure. Although the present disclosure is described in detail with reference to the above embodiments, those skilled in the art should understand that they may still modify the technical solutions described in the above embodiments, or make equivalent substitutions of some or all of the technical features recorded therein, without deviating the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present disclosure.
Number | Date | Country | Kind |
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202111514833.6 | Dec 2021 | CN | national |