CN213026108U - Contact plug structure - Google Patents
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- CN213026108U CN213026108U CN202021410397.9U CN202021410397U CN213026108U CN 213026108 U CN213026108 U CN 213026108U CN 202021410397 U CN202021410397 U CN 202021410397U CN 213026108 U CN213026108 U CN 213026108U
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Abstract
The utility model provides a contact plug structure. The contact plug structure comprises a substrate and a dielectric layer arranged on the substrate, and further comprises: the first contact hole is positioned in the dielectric layer and penetrates into the substrate, the first contact hole is provided with a first through hole section positioned in the dielectric layer and a first groove positioned in the substrate, the first through hole section is communicated with the first groove, and in the direction parallel to the surface of the substrate, the maximum area of the section of the first groove is larger than the maximum area of the section of the first through hole section; the barrier layer at least partially covers the side wall of the first groove; the conductive cushion layer is positioned on the bottom surface of the first groove; and the conductive core layer is arranged on the conductive cushion layer in a contact manner, and the barrier layer wraps the conductive core layer and the conductive core layer. Due to the existence of the barrier layer, in the process of forming the conductive cushion layer, metal ions cannot be transversely diffused into the grid electrode and/or the source and drain electrodes, and the performance of the device is improved.
Description
Technical Field
The utility model relates to a semiconductor device technical field particularly, relates to a contact plug structure.
Background
In a conventional MOS transistor fabrication process, a contact plug (contact plug) is usually formed to conduct a transistor in order to electrically connect a gate and a source/drain of the transistor to a circuit. The contact plug is usually made of a metal conductor such as tungsten, aluminum, copper, etc., but it is not desirable to directly connect to a polycrystalline or single crystalline silicon material such as a gate structure, a source/drain region, etc.
In order to improve the ohm-meter contact (Ohmi contact) between the contact plug and the gate structure, source/drain, an improvement in the prior art is to form a metal silicide (silicide) at the bottom of the contact plug and the gate structure and/or the source/drain contact. However, the metal silicide is usually formed by depositing a layer of Co on the bottom of the contact hole by a sputtering process before forming the contact plug, and forming a thin layer of metal silicide by a thermal treatment, which may cause Co to laterally diffuse into the gate structure and/or the source/drain, thereby affecting the device performance.
SUMMERY OF THE UTILITY MODEL
A primary object of the present invention is to provide a contact plug structure to solve the problem that the preparation process of the contact plug in the prior art easily leads to the reduction of the device performance.
In order to achieve the above object, according to an aspect of the present invention, there is provided a contact plug structure including a substrate and a dielectric layer disposed on the substrate, the contact plug structure further including: the first contact hole is positioned in the dielectric layer and penetrates into the substrate, the first contact hole is provided with a first through hole section positioned in the dielectric layer and a first groove positioned in the substrate, the first through hole section is communicated with the first groove, and in the direction parallel to the surface of the substrate, the maximum area of the section of the first groove is larger than the maximum area of the section of the first through hole section; the barrier layer at least partially covers the side wall of the first groove; the conductive cushion layer is positioned on the bottom surface of the first groove; and the conductive core layer is arranged on the conductive cushion layer in a contact manner, and the barrier layer wraps the conductive core layer and the conductive core layer.
According to another aspect of the present invention, there is provided a contact plug structure, including a substrate and a dielectric layer disposed on the substrate, the contact plug structure further includes: the first contact hole is positioned in the dielectric layer and penetrates into the substrate, the first contact hole is provided with a first through hole section positioned in the dielectric layer and a first groove positioned in the substrate, the first through hole section is communicated with the first groove, and in the direction parallel to the surface of the substrate, the maximum width of the first groove is greater than that of the first through hole section; the barrier layer at least partially covers the side wall of the first groove; the conductive cushion layer is positioned on the bottom surface of the first groove; and the conductive core layer is arranged on the conductive cushion layer in a contact manner, and the barrier layer wraps the conductive core layer and the conductive core layer.
Further, the maximum width of the first groove is greater than the maximum width of the first via section.
Furthermore, in the direction vertical to the surface of the substrate, the arbitrary section of the first groove is a polygon with n sides, the polygon has a group of opposite sides parallel to the surface of the substrate, and n is larger than or equal to 6.
Furthermore, in the direction perpendicular to the surface of the substrate, any section of the first groove is a graph formed by alternately connecting two straight line segments and two arc line segments, and the straight line segments are parallel to the surface of the substrate.
Further, the blocking layer has a first blocking region covering the sidewall of the first groove and a second blocking region covering the sidewall of the first via section.
Further, the thickness of the first barrier region is greater than the thickness of the second barrier region.
According to another aspect of the present invention, there is provided a method for manufacturing the contact plug structure, comprising the steps of: forming a dielectric layer on a substrate, and forming a first contact hole penetrating into the substrate in the dielectric layer, wherein the first contact hole is provided with a first through hole section positioned in the dielectric layer and a first groove positioned in the substrate; forming a barrier layer in the first contact hole so that the barrier layer at least partially covers the side wall of the first groove; and sequentially forming a conductive cushion layer and a conductive core layer in the first contact hole so that the conductive cushion layer is positioned on the bottom surface of the first groove, the conductive core layer is in contact with the conductive cushion layer, and the barrier layer wraps the conductive core layer and the conductive core layer.
Further, the step of forming the barrier layer includes: filling a dielectric material in the first contact hole; the dielectric material is etched to form a second contact hole penetrating to the bottom surface of the first contact hole, and the remaining dielectric material constitutes a barrier layer.
Further, the step of forming the conductive pad layer includes: covering the bottom surface of the second contact hole with a first conductive material by adopting a sputtering process; and carrying out heat treatment on the first conductive material to form a conductive cushion layer.
Further, the step of forming the first contact hole includes: sequentially carrying out dry etching on the dielectric layer and the substrate to form a first through hole penetrating into the substrate; and performing wet etching on the substrate corresponding to the first through hole to transversely expand the part of the first through hole in the substrate to form a first groove, wherein preferably, the etching solution adopted by the wet etching is TMAH.
Further, the method comprises a step of forming a contact plug structure by using the above-mentioned manufacturing method, and the manufacturing method further comprises, before the step of forming the contact plug structure: and after the step of forming the contact plug structure, the dielectric layer covers the grid and the source and drain, and the contact plug structure is in contact with the source and drain.
Use the technical scheme of the utility model, a contact plug structure is provided, include the substrate and set up the dielectric layer on the substrate, this contact plug structure is including being arranged in the dielectric layer and running through to the first contact hole in the substrate, first contact hole has the first through-hole section that is arranged in the dielectric layer and is arranged in the first recess of substrate, first through-hole section and first recess intercommunication, and on the direction that is on a parallel with the substrate surface, the biggest area of first recess cross-section is greater than the biggest area of first through-hole section cross-section, and this contact plug structure still includes the barrier layer, electrically conductive bed course and electrically conductive sandwich layer, the barrier layer is at least partly covered on the lateral wall of first recess, and barrier layer parcel electrically conductive bed course and electrically conductive sandwich layer. Due to the existence of the barrier layer, metal ions cannot be transversely diffused into the substrate in the process of forming the conductive cushion layer, so that when a contact plug in contact with the grid electrode and/or the source drain electrode is formed, the metal ions can be prevented from being transversely diffused into the grid electrode and/or the source drain electrode, and the performance of the device is improved.
Drawings
The accompanying drawings, which form a part of the specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without unduly limiting the scope of the invention. In the drawings:
fig. 1 is a schematic diagram illustrating a cross-sectional structure of a substrate of a contact plug structure according to an embodiment of the present invention;
fig. 2 is a schematic cross-sectional view of a substrate of another contact plug structure provided in an embodiment of the present invention;
fig. 3 is a schematic cross-sectional view of a first groove in a contact plug structure in a direction parallel to a substrate according to the present invention;
fig. 4 is a schematic cross-sectional view of a first groove in a contact plug structure in a direction parallel to a substrate according to another embodiment of the present invention;
fig. 5 is a schematic diagram illustrating a cross-sectional structure of a substrate after a dielectric layer is formed on a substrate and a first contact hole penetrating into the substrate is formed in the dielectric layer in a method for manufacturing a magnetic tunnel junction according to an embodiment of the present invention;
FIG. 6 is a schematic cross-sectional view of the substrate after the first via in FIG. 5 is laterally extended to form a first recess;
FIG. 7 is a schematic cross-sectional view of the substrate after forming a barrier layer in the first contact hole of FIG. 6;
fig. 8 is a schematic cross-sectional view illustrating the substrate after sequentially forming a conductive pad layer and a conductive core layer in the first contact hole shown in fig. 7.
Wherein the figures include the following reference numerals:
10. a substrate; 20. a dielectric layer; 310. a first contact hole; 311. a first via section; 312. a first groove; 320. a first through hole; 330. a second contact hole; 40. a barrier layer; 50. a conductive pad layer; 60. a conductive core layer.
Detailed Description
It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
In order to make the technical solution of the present invention better understood, the technical solution of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall belong to the protection scope of the present invention.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged under appropriate circumstances for purposes of describing the embodiments of the invention herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
As described in the background section, the prior art has been to form a metal silicide at the bottom of the contact plug and the gate structure and/or the source/drain contact to improve the ohmic contact, but the metal silicide is usually formed by a sputtering process and a thermal treatment, which causes the sputtered material to laterally diffuse into the gate structure and/or the source/drain, thereby affecting the device performance.
In order to solve the above technical problem, according to an aspect of the present invention, there is provided a contact plug structure, as shown in fig. 1, including a substrate 10 and a dielectric layer 20 disposed on the substrate 10, the contact plug structure further includes a first contact hole 310, a barrier layer 40, a conductive pad layer 50 and a conductive core layer 60, the first contact hole 310 is located in the dielectric layer 20 and penetrates into the substrate 10, the first contact hole 310 further has a first through hole section 311 located in the dielectric layer 20 and a first groove 312 located in the substrate, the first through hole section 311 is communicated with the first groove 312, and in a direction parallel to the surface of the substrate 10, a maximum area of a cross section of the first groove 312 is greater than a maximum area of a cross section of the first through hole section 311; a barrier layer 40 at least partially covering the sidewalls of the first recess 312; a conductive pad layer 50 on a bottom surface of the first groove 312; the conductive core layer 60 is disposed on the conductive pad layer 50 in contact with the barrier layer 40, and the conductive core layer 60 are wrapped by the barrier layer 40.
Due to the existence of the barrier layer, metal ions cannot be transversely diffused into the substrate in the process of forming the conductive cushion layer, so that when a contact plug in contact with the grid electrode and/or the source drain electrode is formed, the metal ions can be prevented from being transversely diffused into the grid electrode and/or the source drain electrode, and the performance of the device is improved.
According to another aspect of the present invention, there is also provided a contact plug structure, as shown in fig. 1, including a substrate 10 and a dielectric layer 20 disposed on the substrate 10, the contact plug structure further includes a first contact hole 310, a barrier layer 40, a conductive pad layer 50 and a conductive core layer 60, the first contact hole 310 is located in the dielectric layer 20 and penetrates into the substrate 10, the first contact hole 310 further has a first through hole section 311 located in the dielectric layer 20 and a first groove 312 located in the substrate, the first through hole section 311 is communicated with the first groove 312, and in a direction parallel to the surface of the substrate 10, a maximum width of the first groove 312 is greater than a maximum width of the first through hole section 311; a barrier layer 40 at least partially covering the sidewalls of the first recess 312; a conductive pad layer 50 on a bottom surface of the first groove 312; the conductive core layer 60 is disposed on the conductive pad layer 50 in contact with the barrier layer 40, and the conductive core layer 60 are wrapped by the barrier layer 40.
As shown in FIG. 1, the width H of the first groove 3121Is greater than the width H of the first via section 3112。
Similarly, due to the existence of the barrier layer, in the process of forming the conductive cushion layer, metal ions cannot be transversely diffused into the substrate, so that when a contact plug in contact with the grid and/or the source and drain is formed, the metal ions can be prevented from being transversely diffused into the grid and/or the source and drain, and the performance of the device is further improved.
In the above contact plug structure of the present invention, in the direction parallel to the surface of the substrate 10, the maximum area of the cross section of the first groove 312 is greater than the maximum area of the cross section of the first through hole section 311, or the maximum width of the first groove 312 is greater than the maximum width of the first through hole section 311, and the above structure enables the barrier layer 40 located in the first groove 312 to have a larger thickness to prevent the lateral diffusion of the metal ions.
In an alternative embodiment of the present invention, the arbitrary cross-section of the first recess 312 in the first contact hole 310 in the direction perpendicular to the surface of the substrate 10 can be a polygon having n sides, the polygon having a set of opposite sides parallel to the surface of the substrate 10, n ≧ 6.
In the above embodiment, it is preferable that any cross section of the first groove 312 in a direction perpendicular to the surface of the substrate 10 is a hexagon, and any opposite sides of the hexagon are parallel, as shown in fig. 1.
In another alternative embodiment of the present invention, the arbitrary cross section of the first groove 312 is a pattern formed by alternately connecting two straight line segments and two arc segments in a direction perpendicular to the surface of the substrate 10, and the straight line segments are parallel to the surface of the substrate 10, as shown in fig. 2.
In an alternative embodiment of the present invention, the arbitrary cross section of the first groove 312 in the first contact hole 310 in the direction parallel to the surface of the substrate 10 can also be a polygon with n sides, n ≧ 6.
In the above embodiment, it is preferable that an arbitrary cross section of the first groove 312 is hexagonal in a direction parallel to the surface of the substrate 10, as shown in fig. 3.
In another alternative embodiment of the present invention, the arbitrary cross section of the first groove 312 in the direction parallel to the surface of the substrate 10 may also be a pattern formed by two straight line segments and two arc segments alternately connected, as shown in fig. 4.
In the above contact plug structure of the present invention, the blocking layer 40 may have a first blocking region covering on the sidewall of the first groove 312 and a second blocking region covering on the sidewall of the first through hole 311, and in order to improve the blocking effect of the blocking layer 40 on the expanded metal ions, preferably, the thickness of the first blocking region is greater than the thickness of the second blocking region.
The barrier layer 40 may be formed of a dielectric material, and the dielectric material may be selected from one or more of titanium, titanium nitride, tantalum, and tantalum oxide in order to improve the barrier effect of the barrier layer 40 against the expanded metal ions.
In the above contact plug structure of the present invention, the conductive pad layer 50 and the conductive core layer 60 are disposed in the first contact hole 310, and the barrier layer 40 covers the conductive core layer 60 and the conductive core layer 60. The conductive pad layer 50 is used to improve contact resistance, and since the conductive pad layer 50 is usually a metal silicide and is formed by sputtering a metal material such as cobalt and then performing a heat treatment, lateral diffusion of metal ions during sputtering and heat treatment of the metal material can be prevented by the barrier layer 40, thereby improving device performance.
Those skilled in the art can reasonably select the first-generation conductive material forming the conductive pad layer 50 and the second conductive material forming the conductive core layer 60 according to the prior art, the first-generation conductive material can be any one or more of silicided metals such as cobalt, titanium and nickel, the second conductive material can be any one or more of tungsten, aluminum and copper, but the selection is not limited to the above optional types, and those skilled in the art can reasonably select the materials of the conductive pad layer 50 and the conductive core layer 60 according to the prior art.
According to another aspect of the present invention, there is also provided a method for manufacturing the contact plug structure, as shown in fig. 5 to 8, including the following steps: forming a dielectric layer 20 on a substrate 10, and forming a first contact hole 310 penetrating into the substrate 10 in the dielectric layer 20, wherein the first contact hole 310 is provided with a first through hole section 311 positioned in the dielectric layer 20 and a first groove 312 positioned in the substrate 10; forming a barrier layer 40 in the first contact hole 310, so that the barrier layer 40 at least partially covers the sidewall of the first groove 312; the conductive pad layer 50 and the conductive core layer 60 are sequentially formed in the first contact hole 310, such that the conductive pad layer 50 is located on the bottom surface of the first groove 312, the conductive core layer 60 is disposed on the conductive pad layer 50 in a contact manner, and the barrier layer 40 wraps the conductive core layer 60 and the conductive core layer 60.
After the first contact hole is formed, the barrier layer only covering the side wall of the first contact hole is formed, and then the conductive cushion layer and the conductive core layer are sequentially formed, so that the conductive core layer is located on the bottom surface of the first contact hole, the conductive core layer is arranged on the conductive cushion layer in a contact mode, and the barrier layer wraps the conductive core layer and the conductive core layer. Due to the existence of the barrier layer, metal ions cannot be diffused into the substrate transversely in the subsequent process of forming the conductive cushion layer, so that when a contact plug in contact with the grid electrode and/or the source and drain electrodes is formed, the process can prevent the metal ions from being diffused into the grid electrode and/or the source and drain electrodes transversely, and the performance of the device is improved.
A method for manufacturing a contact plug structure according to the present invention will be described in more detail below. These exemplary embodiments may, however, be embodied in many different forms and should not be construed as limited to only the embodiments set forth herein. It is to be understood that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art.
First, a dielectric layer 20 is formed on a substrate 10, and a first contact hole 310 penetrating into the substrate 10 is formed in the dielectric layer 20, the first contact hole 310 having a first via section 311 located in the dielectric layer 20 and a first recess 312 located in the substrate 10, as shown in fig. 5 and 6.
The material of the substrate 10 may be single crystal silicon (Si), single crystal germanium (Ge), silicon germanium (GeSi), or silicon carbide (SiC); or silicon-on-insulator (SOI), germanium-on-insulator (GOI); or may be other materials such as group III-V compounds such as gallium silicide.
In a preferred embodiment, the step of forming the first contact hole 310 includes: sequentially performing dry etching on the dielectric layer 20 and the substrate 10 to form a first through hole 320 penetrating into the substrate 10, as shown in fig. 5; the substrate 10 corresponding to the first via 320 is wet etched to laterally expand the portion of the first via 320 in the substrate 10 to form a first recess 312, as shown in fig. 6.
In an alternative embodiment, the etching solution used in the wet etching is tetramethylammonium hydroxide (TMAH). It should be noted that the process for forming the first contact hole 310 is not limited to the above process combining dry etching and wet etching, and may be implemented by multiple dry etching or multiple wet etching.
Any cross section of the first contact hole 310 parallel to the substrate 10 may be circular, oval, rectangular or irregular; the dielectric layer 20 may be formed by Chemical Vapor Deposition (CVD) or Physical Vapor Deposition (PVD), and the material of the dielectric layer 20 may be nitride or oxide, such as silicon dioxide (SiO)2) Or silicon nitride (SiN).
After the step of forming the first contact hole 310, a barrier layer 40 is formed in the first contact hole 310, such that the barrier layer 40 at least partially covers the sidewalls of the first recess 312 in the substrate 10, as shown in fig. 7.
In a preferred embodiment, the step of forming the barrier layer 40 includes: filling the first contact hole 310 with a dielectric material; the dielectric material is etched to form a second contact hole 330 that penetrates to the bottom surface of the first contact hole 310, and the remaining dielectric material constitutes a barrier layer 40, which barrier layer 40 can have a first barrier region overlying the sidewalls of the first recess 312 and a second barrier region overlying the sidewalls of the first via segment 311.
In the preferred embodiment, the barrier layer 40 can be formed by a conventional etching process in the prior art, such as plasma etching; in order to enhance the barrier effect of the barrier layer 40 against the expanded metal ions, the dielectric material is selected from any one or more of titanium, titanium nitride, tantalum, and tantalum oxide.
After the step of forming the barrier layer 40, the conductive pad layer 50 and the conductive core layer 60 are sequentially formed in the first contact hole 310, such that the conductive pad layer 50 is located on the bottom surface of the first groove 312, the conductive core layer 60 is disposed on the conductive pad layer 50 in a contact manner, and the barrier layer 40 wraps the conductive core layer 60 and the conductive core layer 60, as shown in fig. 8.
In a preferred embodiment, the step of forming the conductive pad layer 50 includes: covering the bottom surface of the second contact hole 330 with a first conductive material by using a sputtering process; the first conductive material is heat-treated to form a conductive pad layer 50.
In the preferred embodiment, the conductive pad layer 50 is typically a metal silicide formed by sputtering a metal material such as cobalt and then performing a heat treatment, and the barrier layer 40 can prevent lateral diffusion of metal ions during sputtering and heat treatment of the metal material, thereby improving device performance. After the step of forming the conductive pad layer 50 by the above-described heat treatment, the unreacted first conductive material in the second contact hole 330 is optionally removed.
According to another aspect of the present invention, there is provided a method for manufacturing a semiconductor device, including the step of forming a contact plug structure by using the above manufacturing method, the manufacturing method further includes, before the step of forming the contact plug structure: forming a grid on the substrate 10, and forming a source drain in the substrate 10 at two sides of the grid, wherein after the step of forming the contact plug structure, the dielectric layer 20 covers the grid and the source drain, and the contact plug structure is in contact with the source drain.
In an optional embodiment, the semiconductor device is a MOS transistor, and the manufacturing method includes: forming a gate on a substrate 10, forming a source drain in the substrate 10 at two sides of the gate, forming a dielectric layer 20 covering the gate and the source drain on the substrate 10, and forming a first contact hole 310 penetrating into the substrate 10 in the dielectric layer 20, wherein the first contact hole 310 has a first through hole section 311 located in the dielectric layer 20 and a first groove 312 located in the substrate 10; forming a barrier layer 40 in the first contact hole 310, so that the barrier layer 40 at least partially covers the sidewall of the first groove 312; a conductive pad layer 50 and a conductive core layer 60 are sequentially formed in the first contact hole 310, so that the conductive pad layer 50 is located on the bottom surface of the first groove 312, the conductive core layer 60 is disposed on the conductive pad layer 50 in a contact manner, the barrier layer 40 wraps the conductive core layer 60 and the conductive core layer 60, and the conductive core layer 60 form a conductive plug and are in contact with the source and drain electrodes.
Because the conventional conductive plug in the prior art is formed only by metal materials such as tungsten, the conduction between the conductive plug and the source/drain electrode made of polysilicon or monocrystalline silicon is not ideal, and the conductive pad layer 50 can improve the contact resistance between the conductive plug and the source/drain electrode.
Between the step of forming the gate and the step of forming the source/drain, the manufacturing method may further include: LDD structures are formed in the substrate 10 at both sides of the gate electrode.
From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects:
due to the existence of the barrier layer, metal ions cannot be transversely diffused into the substrate in the process of forming the conductive cushion layer, so that when a contact plug in contact with the grid electrode and/or the source drain electrode is formed, the process can prevent the metal ions from being transversely diffused into the grid electrode and/or the source drain electrode, and the performance of the device is improved.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (6)
1. A contact plug structure comprising a substrate (10) and a dielectric layer (20) disposed on the substrate (10), characterized in that the contact plug structure further comprises:
a first contact hole (310) located in the dielectric layer (20) and penetrating into the substrate (10), the first contact hole (310) having a first via section (311) located in the dielectric layer (20) and a first groove (312) located in the substrate (10), the first via section (311) being in communication with the first groove (312), and a maximum area of a cross section of the first groove (312) being larger than a maximum area of a cross section of the first via section (311) in a direction parallel to a surface of the substrate (10);
a barrier layer (40) at least partially covering the sidewalls of the first recess (312);
a conductive pad layer (50) on a bottom surface of the first groove (312);
the conductive core layer (60) is arranged on the conductive cushion layer (50) in a contact mode, and the barrier layer (40) wraps the conductive core layer (60) and the conductive core layer (60).
2. A contact plug structure comprising a substrate (10) and a dielectric layer (20) disposed on the substrate (10), characterized in that the contact plug structure further comprises:
a first contact hole (310) located in the dielectric layer (20) and penetrating into the substrate (10), the first contact hole (310) having a first via section (311) located in the dielectric layer (20) and a first groove (312) located in the substrate (10), the first via section (311) being in communication with the first groove (312), and a maximum width of the first groove (312) being greater than a maximum width of the first via section (311) in a direction parallel to a surface of the substrate (10);
a barrier layer (40) at least partially covering the sidewalls of the first recess (312);
a conductive pad layer (50) on a bottom surface of the first groove (312);
the conductive core layer (60) is arranged on the conductive cushion layer (50) in a contact mode, and the barrier layer (40) wraps the conductive core layer (60) and the conductive core layer (60).
3. The contact plug structure according to claim 1 or 2, wherein an arbitrary cross section of the first groove (312) in a direction perpendicular to the surface of the substrate (10) is a polygon having n sides with a set of opposite sides parallel to the surface of the substrate (10), n ≧ 6.
4. The contact plug structure according to claim 1 or 2, wherein an arbitrary cross section of the first groove (312) in a direction perpendicular to the surface of the substrate (10) is a pattern formed by alternately connecting two straight line segments and two arc line segments, the straight line segments being parallel to the surface of the substrate (10).
5. The contact plug structure according to claim 1 or 2, wherein the barrier layer (40) has a first barrier region overlying sidewalls of the first recess (312) and a second barrier region overlying sidewalls of the first via section (311).
6. The contact plug structure according to claim 5, wherein a thickness of the first blocking region is greater than a thickness of the second blocking region.
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| CN202021410397.9U CN213026108U (en) | 2020-07-16 | 2020-07-16 | Contact plug structure |
| US17/235,904 US11551971B2 (en) | 2020-07-16 | 2021-04-20 | Contact plug structure and manufacturing method thereof |
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| CN202021410397.9U CN213026108U (en) | 2020-07-16 | 2020-07-16 | Contact plug structure |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111755403A (en) * | 2020-07-16 | 2020-10-09 | 福建省晋华集成电路有限公司 | Contact plug structure, manufacturing method thereof and manufacturing method of semiconductor device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111755403A (en) * | 2020-07-16 | 2020-10-09 | 福建省晋华集成电路有限公司 | Contact plug structure, manufacturing method thereof and manufacturing method of semiconductor device |
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