The present application claims priority to Chinese Patent Application No. 202011173548.8, entitled “MANUFACTURING METHOD FOR SEMICONDUCTOR STRUCTURE AND SEMICONDUCTOR STRUCTURE”, filed on Oct. 28, 2020, which is incorporated herein by reference in its entirety.
The present disclosure relates to, but is not limited to, a manufacturing method for semiconductor structure and a semiconductor structure.
In a semiconductor structure, a memory is a memory component for storing programs and various data information. A random access memory (RAM) is divided into static random access memory (SRAM) and dynamic random access memory (DRAM). The manufacture and design of the DRAM often involve resistor structures, such as a dropping or current-limiting resistor used in the circuit, a sampling resistor used in the voltage stabilizing circuit or a timing resistor used in the delay circuit.
In order to obtain the resistor structures required by the circuit, a doped polysilicon layer is usually formed on the surface of the substrate of the semiconductor structure. However, this method is complicated, and the manufactured resistor structures occupies a large space, which increases the production cost of the semiconductor structure.
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.
Embodiments of the present disclosure provide a manufacturing method for semiconductor structure and a semiconductor structure, which solve the problems of the resistor structures, such as a complicated manufacturing process, a large space occupied and a high production cost.
A first aspect of the present disclosure provides a manufacturing method for semiconductor structure. The manufacturing method includes: providing a substrate, wherein the substrate includes an array area and a peripheral area; the array area is provided with active area and first isolation structures; the peripheral area is provided with second isolation structures; and forming gate structures in the array area, and simultaneously forming resistor structures in the second isolation structures of the peripheral area by the step of forming the gate structures.
A second aspect of the present disclosure provides a semiconductor structure. The semiconductor structure includes: a substrate, the substrate including an array area and a peripheral area; first isolation structures and active area, the first isolation structures and the active area both being located in the array area; second isolation structures located in the peripheral area; gate structures located in the array area; and resistor structures located in the second isolation structures of the peripheral area.
The embodiments of the present disclosure form resistor structures in the second isolation structures of the peripheral area by the step of forming the gate structures. The embodiments of the present disclosure form the resistor structures by the original step of forming the gate structures, which simplifies the manufacturing step and reduces the manufacturing difficulty. In addition, compared to the resistor structures located on the surface of the substrate, the resistor structures in the present disclosure is located in the space of the original second isolation structures, which saves more space and reduces the production cost.
Other aspects of the present disclosure are understandable upon reading and understanding 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 a 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.
100. substrate; 110. array area; 120. peripheral area; 200. resistor structure; 300. oxide layer; 400. gate structure; 410. barrier layer; 420. conductive layer; 500. first isolation structure; 600. second isolation structure; 700. insulating layer; 800. active area;
10. substrate; 11. array area; 12. peripheral area; 21. first isolation structure; 22. second isolation structure; 31. gate structure; 32. resistor structure; 41. first trench; 42. second trench; 51a. mask layer; 51. patterned mask layer; 52. patterned lithography layer; 61a. initial oxide layer; 61. oxide layer; 62a. initial barrier layer; 62. barrier layer; 621. first barrier layer; 622. second barrier layer; 63a. initial conductive layer; 63. conductive layer; 631. first conductive layer; 632. second conductive layer; 71. insulating layer; 80. active area.
The technical solutions in embodiments of the present disclosure are described below clearly and completely with reference to the drawings in the embodiments of the present disclosure. Apparently, the described embodiments are merely part rather than 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.
As mentioned in the background, the resistor structures in the related art have problems such as a complicated manufacturing process, a large space occupied and a high production cost.
The resistor structures 200 can only be manufactured after the gate structures 400 and the oxide layer 300 in the array area 110 are manufactured. The whole manufacturing process involves many steps and is complicated. In addition, the resistor structures 200 are usually formed on the surface of the substrate 100, which occupy a large space, and the space in the second isolation structures 600 is not fully utilized, which leads to a high production cost.
An embodiment of the present disclosure provides a manufacturing method for semiconductor structure. The manufacturing method includes: simultaneously form resistor structures in second isolation structures of a peripheral area by the step of forming gate structures. The embodiment of the present disclosure forms the resistor structures by the original step of forming the gate structures, which simplifies the manufacturing step and reduces the manufacturing difficulty. In addition, since the resistor structures are formed in the second isolation structures, the space in the second isolation structures is fully utilized, which reduces the space occupied by the resistor and reduces the production cost.
A first embodiment of the present disclosure provides a manufacturing method for semiconductor structure.
Referring to
In this embodiment, the surface of the substrate 10 may also be used to form resistor structures, other logic control device or array device used in a circuit. The surface and internal space of the substrate 10 can be utilized, which improves the space utilization of the semiconductor structure.
The substrate 10 has multiple active areas 80, and the first isolation structures 21 are configured to isolate adjacent active areas 80 in the array area 11.
In this embodiment, the first isolation structures 21 and the second isolation structures 22 are shallow trench isolation (STI) structures.
Referring to
The resistor structures 32 are formed in the second isolation structures 22 by the manufacturing step and a photomask required for forming the gate structures 31, which simplifies the production process and reduces the production difficulty and cost. In addition, the resistor structures 32 utilize the space of the original second isolation structures 22, which improves the space utilization, thereby reducing the size of the semiconductor structure and reducing the production cost.
The gate structures 31 are located in the active area 80 and the first isolation structures 21 of the array area 11.
The gate structures 31 and the resistor structures 32 are formed as follows:
Referring to
The first trenches 41 serve as filling space to form the gate structures later, and the second trenches 42 serve as filling space to form the resistor structures later.
The first trenches 41 are located in the active area 80 and the first isolation structures 21 of the array area 11. The cross-sectional shape of the first trenches 41 or the second trenches 42 includes a square shape or a U shape.
In this embodiment, there are two second trenches 42 located in the same second isolation structure 22. In other embodiments, there may be one, three or more than three second trenches in the same second isolation structure, and the number of the second trenches may be designed according to actual needs.
In order to form resistor structures of different volumes, the opening widths and depths of the multiple second trenches 42 located in the same second isolation structure 22 may be different, and the opening widths and depths of the multiple second trenches 42 located in different second isolation structures 22 may also be different.
The depth of each of the second trenches 42 is smaller than that of the second isolation structures 22. In this way, the second isolation structures 22 can cover the bottom of the resistor structures formed subsequently, so as to avoid problems such as leakage and interference of the resistor structures, thereby improving the stability of the resistor structures and other structures in the circuit.
It is understandable that the depth of the first trenches 41 located in the first isolation structures 21 is smaller than that of the first isolation structures 21.
The first trenches 41 and the second trenches 42 are formed as follows:
Referring to
In this embodiment, the material of the mask layer 51a includes silicon nitride, silicon oxynitride or silicon carbide, etc. In this embodiment, the mask layer 51a has a single-layer structure. In other embodiments, the mask layer may also have a multi-layer structure.
Referring to
In this embodiment, after the patterned mask layer 51 is formed, the patterned lithography layer 52 is removed.
Referring to
In this embodiment, after the first trenches 41 and the second trenches 42 are formed, the patterned mask layer 51 is removed.
In this embodiment, only one patterned mask layer 51 is configured to form the first trenches 41 and the second trenches 42. In other embodiments, a double patterning process may also be used to form the first trenches and the second trenches. Alternatively, in other embodiments, there may be no need to form a patterned mask layer. Instead, a patterned lithography layer is directly formed on the surface of the substrate, and the patterned lithography layer is used as a mask to etch the substrate to form the first trenches and the second trenches.
Referring to
In this embodiment, the initial oxide layer 61a is made of silicon oxide. In other embodiments, the material of the initial oxide layer may also have a high dielectric constant. Generally, a chemical vapor deposition (CVD) process or an atomic layer deposition (ALD) process is used to form the initial oxide layer 61a.
In this embodiment, the initial barrier layer 62a is made of titanium nitride. In other embodiments, the material of the initial barrier layer may also include tantalum nitride, etc. The initial barrier layer 62a may be formed by a CVD process or an ALD process.
Referring to
Referring to
Referring to
In this embodiment, part of the initial conductive layer 63a, part of the initial barrier layer 62a and part of the initial oxide layer 61a that are higher than the substrate 10 are removed by a chemical mechanical polishing (CMP) process. Part of the initial conductive layer 63a, part of the initial barrier layer 62a and part of the initial oxide layer 61a which are located in the substrate 10 are etched back to form the conductive layer 63, the barrier layer 62 and the oxide layer 61. The conductive layer 63 is located on the barrier layer 62, and the barrier layer 62 is located on the oxide layer 61.
In some embodiments, referring to
The conductive layer 63 (shown in
In this embodiment, since the first conductive layer 631 and the second conductive layer 632 are formed in the same manufacturing step, the second conductive layer 632 and the first conductive layer 631 may be made of the same material, which may be tungsten or titanium.
In other embodiments, the material of the first conductive layer and the second conductive layer may also be polysilicon or doped polysilicon.
A first barrier layer 621 and a first conductive layer 631 constitute a gate structure 31. The first barrier layer 621 can prevent the material of the first conductive layer 631 from diffusing into the oxide layer 61, thereby ensuring the stability of the semiconductor device.
A second barrier layer 622 and a second conductive layer 632 constitute a resistor structure 32. The second barrier layer 622 can prevent the material of the second conductive layer 632 from diffusing into the second isolation structure 22, thereby improving the stability of the resistor structure 32.
The manufacturing method further includes: form an insulating layer 71 on surfaces of the gate structures 31, surfaces of the resistor structures 32 and the surface of the substrate 10, so as to prevent the gate structures 31 from being oxidized in a subsequent process.
The insulating layer 71 may be subsequently etched to form through holes exposing the resistor structures 32. A conductive material is filled in the through holes to realize the electrical connection between the resistor structure 32 and other structure or circuit.
It is understandable that the insulating layer 71 may be etched subsequently to form recesses in the insulating layer 71. A conductive material is filled in the recesses to form surface resistor structures located on the surface of the substrate 10. In addition, other logic control device or array device may also be formed in the recesses. The surface and internal space of the substrate 10 can be utilized, which improves the space utilization of the semiconductor structure and reduces the size of the semiconductor structure.
In summary, in this embodiment, the resistor structures 32 and the gate structures 31 are formed in the same manufacturing step, which simplifies the production process and reduces the production cost. In addition, the resistor structures 32 are located in the second isolation structures 22, which saves the space, reduces the size of the semiconductor structure, and reduces the production cost.
A second embodiment of the present disclosure provides a semiconductor structure. The semiconductor structure may be manufactured by the manufacturing method for semiconductor structure provided in the first embodiment.
Referring to
The gate structures 31 are located in the active area 80 and the first isolation structures 21 of the array area 11.
At least one resistor structures 32 is provided in the same second isolation structure 22. Multiple resistor structures 32 may have different volumes, widths c and thicknesses b. It is understandable that multiple resistor structures 32 in different second isolation structures 22 may also have different volumes, different widths c and different thicknesses b. In this way, the requirements of the circuit for different resistor structures 32 can be met.
The gate structures 31 each includes a first barrier layer 621 and a first conductive layer 631, and the first conductive layer 631 covers a surface of the first barrier layer 621. The resistor structures 32 each includes a second conductive layer 632 and a second barrier layer 622, and the second conductive layer 632 covers a surface of the second barrier layer 622. That is, in the gate structure 31, the first conductive layer 631 is located on the first barrier layer 621, and in the resistor structure 32, the second conductive layer 632 is located on the second barrier layer 622.
The resistor structures 32 and the gate structures 31 are made of the same material. For example, the first conductive layer 631 and the second conductive layer 632 are made of tungsten or titanium, and the first barrier layer 621 and the second barrier layer 622 are made of titanium nitride or tantalum nitride.
The semiconductor structure provided in this embodiment further includes an insulating layer 71. The insulating layer 71 covers surfaces of resistor structures 32, surfaces of the gate structures 31 and surfaces of the substrate 10. The insulating layer 71 can protect the resistor structures 32 and the gate structures 31 from being oxidized.
The semiconductor structure provided in this embodiment further includes oxide layer 61. The oxide layer 61 is located in the substrate 10. The gate structures 31 and the resistor structures 32 cover the surface of the oxide layer 61, that is, the gate structures 31 and the resistor structures 32 are located on the oxide layer 61.
In summary, the resistor structures 32 are located in the second isolation structures 22, which saves the space and reduces the size of the semiconductor structure. In addition, the volumes of resistor structures 32 located in the same second isolation structure 22 may be different to meet the requirements of the circuit for different resistor structures 32.
Each embodiment in the specification of the present disclosure is described in a progressive manner. Each embodiment focuses on the difference from other embodiments, and the same and 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 implementation or example. Moreover, the described specific feature, structure, material or feature may be combined in an appropriate manner in any one or more implementations 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 should be understood that the terms such as “first” and “second” used herein may 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 multiple 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.
The present disclosure provides a manufacturing method for semiconductor structure and a semiconductor structure. The present disclosure simultaneously forms resistor structures in the second isolation structures of the peripheral area by the step of forming gate structures, which simplifies the manufacturing step and reduces the manufacturing difficulty. In addition, since the resistor structures are formed in the second isolation structures, the space in the second isolation structures is fully utilized, which reduces the space occupied by the resistor and reduces the production cost.
Number | Date | Country | Kind |
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202011173548.8 | Oct 2020 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2021/103852 | 6/30/2021 | WO |