Semiconductor device and method for forming the same

Abstract

The present invention provides a semiconductor device and a method for forming the same, comprising the following steps: providing a substrate, forming a metal gate groove on one side of the substrate; cutting the metal gate groove along the width extension direction of the metal gate groove to form a cutting groove; depositing an isolation material in the projection area of ​​the overlapping part of the metal gate groove and the cutting groove in the metal gate groove, and depositing an isolation material in the remaining area of ​​the cutting groove; depositing a metal gate material in the remaining area of ​​the metal gate groove to form a metal gate structure. The semiconductor device and the method for forming the same provided by the present invention effectively avoid the problem in the prior art that a metal gate is first formed on a substrate, and then the metal gate is etched to form a cutting groove, while the metal gate has a large hardness and is difficult to etch, and is not easy to form an isolation structure; or, the isolation structure is first formed, and then the metal gate is formed, and there will be substrate residues on both sides of the metal gate, resulting in poor performance of the semiconductor device.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a semiconductor device and a method for forming the same. Background Art

[0002] As the semiconductor industry has developed into nanotechnology process nodes that pursue higher device density, higher performance and lower cost, the manufacturing of semiconductor devices has encountered unprecedented challenges.

[0003] In the prior art, the following two methods are usually used to form the metal gate and cutting groove of the semiconductor device. In the first method, a metal gate is first formed on a substrate, and then the metal gate is etched to form a cutting groove, and an isolation material is filled in the cutting groove to form an isolation structure to isolate the metal gate. However, the hardness of the material of the metal gate is usually relatively large, so it is relatively difficult to etch, and it is not easy to form the required cutting groove, which affects the performance of the metal gate. In another method, a cutting groove is first formed, and then a metal gate groove and a metal gate are formed. At this time, there will be substrate material (amorphous silicon) residues formed by etching the substrate on both sides of the metal gate filled in the metal gate groove, and the photoresist when the metal gate is formed is also easy to form residues, resulting in poor performance of the semiconductor device. In addition, this method is also relatively easy to form a metal gate that is high on one side and low on the other side, so that the height of the effective fin is affected, thereby reducing the saturation current.

[0004] Therefore, the present invention aims to provide a semiconductor device and a method for forming the same, so as to form a semiconductor device with better performance. Summary of the invention

[0005] The purpose of the present invention is to solve the problem of poor performance of semiconductor devices in the prior art.

[0006] The present invention provides a method for forming a semiconductor device, comprising the following steps: providing a substrate, forming a metal gate groove on one side of the substrate; cutting the metal gate groove along the width extension direction of the metal gate groove to form a cutting groove; depositing an isolation material in a projection area of ​​an overlapping portion of the metal gate groove and the cutting groove in the metal gate groove to form an isolation structure; and depositing a metal gate material in the remaining area of ​​the metal gate groove to form a metal gate structure.

[0007] By adopting the above technical scheme, the present invention provides a method for forming a semiconductor device, comprising the following steps: providing a substrate, forming a metal gate groove on one side of the substrate; cutting the metal gate groove along the width extension direction of the metal gate groove to form a cutting groove; depositing an isolation material in the projection area of ​​the overlapping part of the metal gate groove and the cutting groove in the metal gate groove to form an isolation structure; and depositing a metal gate material in the remaining area of ​​the metal gate groove to form a metal gate structure.

[0008] The method for forming a semiconductor device provided by the present invention first forms a metal gate groove on a substrate, then forms a cutting groove, and after filling the cutting groove with an isolation material to form an isolation structure, fills the metal gate groove with a metal gate material to form a metal gate structure, effectively avoiding the problem in the prior art that a metal gate is first formed on a substrate and then the metal gate is etched to form a cutting groove, but the metal gate has a large hardness and is difficult to etch, making it difficult to form a required isolation structure; or, first forms an isolation structure and then forms a metal gate, and there will be substrate material residues on both sides of the metal gate, which affects the performance of the metal gate, thereby causing poor performance of the semiconductor device.

[0009] According to another specific embodiment of the present invention, forming a metal gate trench on one side of a substrate includes the following steps:

[0010] A gate fin is formed on one side of the substrate, a dummy gate is formed across the gate fin, and a first gate oxide film layer is deposited at the position where the gate fin contacts the dummy gate; an interlayer dielectric layer is deposited around the dummy gate; the dummy gate is removed to form a metal gate trench.

[0011] By adopting the above technical scheme, the present invention first forms a metal gate groove on a substrate, then forms a cutting groove, fills the cutting groove with an isolation material to form an isolation structure, and then fills the metal gate groove with a metal gate material to form a metal gate structure.

[0012] Furthermore, when forming a metal gate trench, a gate fin is first formed on one side of the substrate, and each gate fin provides an active area corresponding to one or more devices. When forming the gate fin, a mask layer can be formed on the substrate, a photoresist layer is formed on the mask layer, the photoresist layer is exposed to the photoresist pattern, baked after exposure, and the photoresist layer is developed to pattern the photoresist layer to form a gate fin. The gate fin spans the gate fin to form a dummy gate, and the dummy gate serves as a reserved position for the actual gate formed thereon later; and a first gate oxide film layer is deposited at the position where the gate fin contacts the dummy gate; an interlayer dielectric layer is deposited around the dummy gate; and finally, the dummy gate is removed, and the space on the substrate after the dummy gate is removed forms a metal gate trench.

[0013] According to another specific embodiment of the present invention, after the metal gate trench is formed, it also includes: depositing a second gate oxide film layer and a work function metal layer in sequence on the inner side of the metal gate trench, wherein a gate dielectric layer is also deposited on the inner wall of the metal gate trench, and the second gate oxide film layer is in contact with the gate dielectric layer and the work function metal layer respectively; and a work function metal layer is also deposited on the side of the interlayer dielectric layer away from the substrate.

[0014] By adopting the above technical solution, after forming the metal gate trench, the second gate oxide film layer and the work function metal layer can be sequentially deposited on the inner side of the metal gate trench, wherein a gate dielectric layer is also deposited on the inner wall of the metal gate trench, and the second gate oxide film layer is in contact with the gate dielectric layer and the work function metal layer respectively. That is to say, the metal gate to be formed finally includes the gate dielectric layer, the second gate oxide film layer and the work function metal layer sequentially deposited on the inner side of the metal gate trench.

[0015] According to another specific embodiment of the present invention, it also includes: depositing a spin-coated carbon material on a side of the work function metal layer away from the substrate; etching the spin-coated carbon material along the width extension direction of the metal gate groove according to the cutting groove pattern, removing the spin-coated carbon material corresponding to the cutting groove pattern in the metal gate groove, removing the spin-coated carbon material corresponding to the cutting groove pattern deposited on the side of the interlayer dielectric layer away from the substrate, and removing part of the interlayer dielectric layer corresponding to the cutting groove pattern to form a cutting groove.

[0016] The above technical solution is adopted to deposit a spin-coated carbon material on the side of the work function metal layer away from the substrate. The spin-coated carbon material is used as an etching stop layer to block the subsequent etching of the spin-coated carbon material corresponding to the cutting groove pattern in the metal gate groove according to the cutting groove pattern along the width extension direction of the metal gate groove. The spin-coated carbon material is etched according to the cutting groove pattern along the width extension direction of the metal gate groove, and the spin-coated carbon material corresponding to the cutting groove pattern in the metal gate groove is removed, and the spin-coated carbon material corresponding to the cutting groove pattern deposited on the side of the interlayer dielectric layer away from the substrate is removed, and part of the interlayer dielectric layer corresponding to the cutting groove pattern is removed to form a cutting groove.

[0017] According to another specific embodiment of the present invention, when removing the spin-coated carbon material, it also includes: removing the second gate oxide film layer and the work function metal layer on the side of the metal gate trench close to the substrate.

[0018] According to another specific embodiment of the present invention, before depositing the metal gate material, the method further includes: removing the remaining area of ​​the metal gate groove and the spin-coated carbon material deposited on the side of the work function metal layer deposited on the side of the interlayer dielectric layer away from the substrate.

[0019] By adopting the above technical solution, before depositing the metal gate material, the spin-coated carbon material deposited on the remaining area of ​​the metal gate groove and the work function metal layer deposited on the side of the interlayer dielectric layer away from the substrate and the side away from the substrate can be removed to facilitate the subsequent filling of the metal gate material to form a metal gate structure.

[0020] According to another specific embodiment of the present invention, the isolation material includes: at least one of silicon oxide, silicon nitride, silicon oxynitride, and silicate glass; the spin-coated carbon material includes: at least one of silicon oxide, silicon nitride, and silicon oxynitride; the metal gate material includes: at least one of chromium oxide, thallium chloride, titanium chloride, and titanium nitride.

[0021] According to another specific embodiment of the present invention, when depositing the isolation material in the projection area of ​​the overlapping part of the metal gate groove and the cutting groove in the metal gate groove, it also includes: depositing the isolation material in the remaining area of ​​the cutting groove; before depositing the metal gate material, it also includes: etching and removing part of the isolation material filled in the cutting groove to form a cutting groove opening.

[0022] By adopting the above technical solution, when the isolation material is deposited in the projection area of ​​the overlapping part of the metal gate groove and the cutting groove in the metal gate groove, it also includes: depositing the isolation material in the remaining area of ​​the cutting groove; before depositing the metal gate material, it also includes the following steps: etching and removing part of the isolation material filled in the cutting groove to form a cutting groove opening to interrupt the longitudinal extension of the metal gate, and later using the isolation material to cut the groove opening to form an isolation area to isolate the metal gate.

[0023] According to another specific embodiment of the present invention, the shape of the cutting groove opening is shuttle-shaped, and S1≥S2, wherein S1 is the distance from the edge area of ​​the end face of the cutting groove opening to the substrate, and S2 is the distance from the middle area of ​​the end face of the cutting groove opening to the substrate.

[0024] By adopting the above technical solution, in order to achieve a better effect when the cutting groove opening interrupts the longitudinal extension of the metal gate, the shape of the cutting groove opening can be a shuttle shape, and S1≥S2, where S1 is the distance from the edge area of ​​the end surface of the cutting groove opening to the substrate, and S2 is the distance from the middle area of ​​the end surface of the cutting groove opening to the substrate. In other words, the cutting groove opening is a structure that protrudes toward one side of the substrate.

[0025] According to another specific embodiment of the present invention, a semiconductor device is manufactured based on the above-mentioned method for forming a semiconductor device.

[0026] By adopting the above technical scheme, the semiconductor device of the present invention is manufactured based on the above semiconductor device formation method. The semiconductor device first forms a metal gate groove on the substrate, then forms a cutting groove, and after the isolation material is filled in the cutting groove to form an isolation structure, the metal gate material is filled in the metal gate groove to form a metal gate structure. The problem of the prior art that a metal gate is first formed on the substrate, and then the metal gate is etched to form a cutting groove, but the hardness of the metal gate is relatively large, it is difficult to etch, and it is not easy to form the required isolation structure; or the substrate is first etched to form an isolation structure, and then the metal gate is formed, and there will be substrate material residues on both sides of the metal gate, which affects the performance of the metal gate, and thus causes the problem of poor performance of the semiconductor device.

[0027] The beneficial effects of the present invention are:

[0028] The present invention provides a method for forming a semiconductor device, comprising the following steps: providing a substrate, forming a metal gate groove on one side of the substrate; cutting the metal gate groove along the width extension direction of the metal gate groove to form a cutting groove; depositing an isolation material in the projection area of ​​the overlapping part of the metal gate groove and the cutting groove in the metal gate groove to form an isolation structure; depositing a metal gate material in the remaining area of ​​the metal gate groove to form a metal gate structure. The method for forming a semiconductor device provided by the present invention effectively avoids the problem in the prior art that a metal gate is first formed on a substrate, and then the metal gate is etched to form a cutting groove, while the metal gate has a large hardness and is difficult to etch, and it is not easy to form an isolation structure; or, first the substrate is etched to form an isolation structure, and then the metal gate is formed, and there will be substrate residues on both sides of the metal gate, resulting in poor performance of the metal gate of the semiconductor device. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A flow chart of a method for forming a semiconductor device provided by an embodiment of the present invention;

[0030] Figure 2a-10a A process flow chart of forming a semiconductor device provided by an embodiment of the present invention, wherein the section direction of the semiconductor device is parallel to the length direction of the metal gate trench;

[0031] Figure 2b-10b The embodiment of the present invention provides Figure 2a-10a A corresponding process flow chart for forming a semiconductor device, wherein the section direction of the semiconductor device is parallel to the width direction of the metal gate trench.

[0032] Reference numerals:

[0033] 100: substrate; 110: gate fin; 120: dummy gate; 130: first gate oxide film layer; 140: interlayer dielectric layer;

[0034] 200: metal gate trench; 210: second gate oxide film layer; 220: work function metal layer; 230: gate dielectric layer; 240: spin-coated carbon material;

[0035] 300: cutting groove; 310: isolation material; 320: cutting groove opening;

[0036] 400: metal gate structure; 410: metal gate material. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is described clearly and completely below through the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present invention.

[0039] Furthermore, the terms “first”, “second” and “third” are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or a connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the meanings of the above terms in the present invention can be understood in specific circumstances.

[0041] The invention aims to solve the problem of poor performance of semiconductor devices in the prior art.

[0042] like Figure 1 As shown, this embodiment provides a method for forming a semiconductor device, comprising the following steps:

[0043] S11: providing a substrate, and forming a metal gate trench on one side of the substrate.

[0044] like Figure 3bAs shown, a substrate 100 is provided, and a metal gate trench 200 is formed on one side of the substrate 100 .

[0045] like Figure 2a , Figure 2b As shown, specifically, forming a metal gate trench 200 on one side of a substrate 100 includes the following steps: forming a gate fin 110 on one side of the substrate 100, forming a dummy gate 120 across the gate fin 110, and depositing a first gate oxide film layer 130 at a position where the gate fin 110 contacts the dummy gate 120. In addition, after forming the dummy gate 120 across the gate fin 110, a side of the dummy gate 120 away from the substrate 100 is subjected to mechanical chemical polishing (CMP, Chemical Mechanical Polishing).

[0046] like Figure 3a , Figure 3b As shown, an interlayer dielectric layer 140 is deposited around the dummy gate 120 ; the dummy gate 120 is removed to form a metal gate trench 200 .

[0047] Specifically, in this embodiment, a metal gate trench 200 is first formed on the substrate 100. When forming the metal gate trench 200, a gate fin 110 is first formed on one side of the substrate 100. Each gate fin 110 provides multiple active areas corresponding to one or more devices. When forming the gate fin 110, a mask layer can be formed on the substrate 100, a photoresist layer is formed on the mask layer, the photoresist layer is exposed to the photoresist pattern, and baking is performed after exposure. The photoresist layer is developed to pattern the photoresist layer to form the gate fin 110. A dummy gate 120 is formed across the gate fin 110, and the dummy gate 120 serves as a reserved position for the actual gate thereon later; and a first gate oxide film layer 130 is deposited at the position where the gate fin 110 contacts the dummy gate 120; an interlayer dielectric layer 140 is deposited around the dummy gate 120; and finally, the dummy gate 120 is removed, and the space on the substrate 100 after the dummy gate 120 is removed forms the metal gate trench 200. At this time, a gate dielectric layer 230 and a second gate oxide film layer 210 are sequentially deposited on the inner wall of the metal gate trench 200 , and the gate dielectric layer 230 is located between the inner wall of the metal gate trench 200 and the second gate oxide film layer 210 .

[0048] More specifically, the material of the substrate 100 can be selected from at least one of crystalline silicon, silicon oxide, strained silicon, silicon germanium, doped or undoped polysilicon, doped or undoped silicon wafer and patterned or unpatterned silicon on insulator wafer (SOI), carbon-doped silicon oxide, silicon nitride, doped silicon, germanium, gallium arsenide, glass and sapphire.

[0049] In the present embodiment, the substrate 100 is a silicon-containing material such as a crystalline silicon substrate. In addition, the substrate 100 is not limited to any specific size, shape or material. The substrate 100 can be a circular or annular substrate with a diameter of 200 mm, a diameter of 300 mm or other diameters such as 450 mm. The substrate 100 can also be any polygon, such as a square, a rectangle, a curved or other non-circular workpiece. This embodiment does not specifically limit this.

[0050] In addition, the gate fin 110 has a width of about 10 nanometers (nm) and a height between about 10 nm and 60 nm (such as about 50 nm high). However, it should be understood that other sizes may also be used for the gate fin 110. The gate fin 110 includes a silicon material or another element semiconductor such as germanium, a compound semiconductor including silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, indium arsenide and / or indium antimonide. The gate fin 110 may be doped with an n-type dopant and / or a p-type dopant as needed. In some embodiments, the gate fin 110 may be formed by any suitable process including various deposition, photolithography and / or etching processes. In this example, the gate fin 110 is formed by patterning and etching a portion of the substrate 100. The specific manufacturing process and size material of the gate fin 110 may be selected according to actual needs, and this embodiment is not specifically limited to this.

[0051] like Figure 4a , Figure 4b As shown, after the metal gate trench 200 is formed, the method further includes: depositing a second gate oxide film layer 210 and a work function metal layer 220 in sequence on the inner side of the metal gate trench 200. A gate dielectric layer 230 is deposited on the inner wall of the metal gate trench 200, and the second gate oxide film layer 210 is in contact with the gate dielectric layer 230 and the work function metal layer 220 respectively; and the work function metal layer 220 is also deposited on the side of the interlayer dielectric layer 140 away from the substrate 100.

[0052] Specifically, after forming the metal gate trench 200, the method further includes: depositing a second gate oxide film layer 210 and a work function metal layer 220 in sequence on the inner side of the metal gate trench 200. A gate dielectric layer 230 is deposited on the inner wall of the metal gate trench 200, and the second gate oxide film layer 210 is in contact with the gate dielectric layer 230 and the work function metal layer 220 respectively; and the work function metal layer 220 is also deposited on the side of the interlayer dielectric layer 140 away from the substrate 100. In other words, the metal gate to be formed finally includes the gate dielectric layer 230, the second gate oxide film layer 210 and the work function metal layer 220 deposited in sequence on the inner side of the metal gate trench 200.

[0053] It should be understood that the material of the second gate oxide film layer 210 can be one of silicon oxide and silicon oxynitride, which can be selected according to actual needs and is not specifically limited in this embodiment.

[0054] The material of the gate dielectric layer 230 may be HK high-k materials, such as silicon nitride, aluminum nitride, titanium oxide, etc., which may be selected according to actual needs and is not specifically limited in this embodiment.

[0055] The material of the work function metal layer 220 may be at least one of chromium oxide, thallium chloride, titanium chloride, and titanium nitride, and the material may be selected according to actual needs, and this embodiment does not specifically limit this.

[0056] like Figure 5a , Figure 5b As shown, the method further includes: depositing a spin-on carbon material 240 in the metal gate trench 200 and on the side of the work function metal layer 220 deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 away from the substrate 100. The spin-on carbon material 240 is used to protect the work function metal layer 220 deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 from being affected in subsequent etching.

[0057] S12: cutting the metal gate trench along a width extension direction of the metal gate trench to form a cut trench.

[0058] like Figure 6a , Figure 6b As shown, the spin-coated carbon material 240 is etched according to the cutting groove pattern along the width extension direction of the metal gate groove 200, the spin-coated carbon material 240 corresponding to the cutting groove pattern in the metal gate groove 200 is removed, the spin-coated carbon material 240 corresponding to the cutting groove pattern deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 is removed, and part of the interlayer dielectric layer 140 corresponding to the cutting groove pattern is removed to form a cutting groove 300.

[0059] Specifically, a spin-on carbon material 240 is deposited in the metal gate trench 200 and on the side of the work function metal layer 220 deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 away from the substrate 100. The spin-on carbon material 240 is used as an etching stop layer to block the subsequent etching of the spin-on carbon material 240 corresponding to the cutting groove pattern in the metal gate trench 200 according to the cutting groove pattern along the width extension direction of the metal gate trench 200. When the spin-on carbon material 240 corresponding to the cutting groove pattern deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 and the part of the interlayer dielectric layer 140 corresponding to the cutting groove pattern are removed to form the cutting groove 300, the remaining area of ​​the metal gate trench 200 and the work function metal layer 220 deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 will be etched. In addition, the spin-on carbon material 240 is deposited on the side of the work function metal layer 220 away from the substrate 100.

[0060] In addition, the spin-coated carbon material 240 (SOC material:) may include at least one of silicon oxide, silicon nitride, and silicon oxynitride, and may not be limited to the specific material of the spin-coated carbon material 240 given in this embodiment. The specific material can be selected according to actual needs, and this embodiment does not make any specific limitations on this.

[0061] like Figure 6a , Figure 6b As shown, when removing the spin-on carbon material 240 , the process also includes: removing the second gate oxide film layer 210 and the work function metal layer 220 on the side of the metal gate trench 200 close to the substrate 100 .

[0062] like Figure 7a , 7b As shown, when the spin-on carbon material 240 is removed, the work function metal layer 220 is also included in the projected area of ​​the overlapping portion of the metal gate trench 200 and the cutting trench 300 .

[0063] S13: Depositing an isolation material in a projection area of ​​an overlapping portion of the metal gate trench and the cutting trench in the metal gate trench to form an isolation structure.

[0064] like Figure 8a , Figure 8bAs shown, an isolation material 310 is deposited in the projection area of ​​the overlapping portion of the metal gate groove 200 and the cutting groove 300 in the metal gate groove 200 to form an isolation structure. The method for forming a semiconductor device provided in this embodiment first forms a metal gate groove 200 on a substrate 100, then forms a cutting groove 300, and fills the cutting groove 300 with an isolation material 310 to form an isolation structure to interrupt the longitudinal extension of the metal gate. In addition, the isolation material 310 includes: at least one of silicon oxide, silicon nitride, silicon oxynitride, and silicate glass, which can be selected according to actual needs, and this embodiment does not specifically limit this.

[0065] like Figure 9a , Figure 9b As shown, when the isolation material 310 is deposited in the projection area of ​​the metal gate trench 200 where the metal gate trench 200 overlaps with the cutting trench 300, the method further includes: depositing the isolation material 310 in the remaining area of ​​the cutting trench 300. Before depositing the metal gate material, the method further includes: etching the isolation material 310 filled in the cutting trench 300 to form a cutting trench opening 320.

[0066] Specifically, when the isolation material 310 is deposited in the projection area of ​​the overlapping portion of the metal gate trench 200 and the cutting trench 300 in the metal gate trench 200, the isolation material 310 is deposited in the remaining area of ​​the cutting trench 300. Before depositing the metal gate material, the isolation material 310 filled in the cutting trench 300 is etched to form a cutting trench opening 320 to interrupt the longitudinal extension of the metal gate, and the trench opening 320 is cut with the isolation material 310 to form an isolation region to isolate the metal gate.

[0067] like Figure 9a , Figure 9b As shown, the shape of the cutting groove opening 320 is shuttle-shaped, and S1 ≥ S2, wherein S1 is the distance from the edge area of ​​the end surface of the cutting groove opening 320 to the substrate 100, and S2 is the distance from the middle area of ​​the end surface of the cutting groove opening 320 to the substrate 100.

[0068] Specifically, in order to achieve a better effect when the cutting groove opening 320 interrupts the longitudinal extension of the metal gate, the shape of the cutting groove opening 320 can be designed to be a shuttle shape, and S1 ≥ S2, where S1 is the distance from the edge area of ​​the end surface of the cutting groove opening 320 to the substrate 100, and S2 is the distance from the middle area of ​​the end surface of the cutting groove opening 320 to the substrate 100. In other words, the cutting groove opening 320 can be a structure that protrudes toward one side of the substrate 100.

[0069] like Figure 9a , Figure 9bAs shown, before depositing the metal gate material, the process also includes: removing the remaining area of ​​the metal gate trench 200 , and removing the spin-on carbon material 240 deposited on the side of the work function metal layer 220 deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 .

[0070] Specifically, before depositing the metal gate material, the remaining area of ​​the metal gate groove 200, as well as the work function metal layer 220 deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 and the spin-coated carbon material 240 deposited on the side of the substrate 100 away from the substrate 100 can be removed to facilitate the subsequent filling of the metal gate material to form a metal gate structure.

[0071] According to another specific embodiment of the present invention, the isolation material (Silicon On Glass, SOG) includes: at least one of silicon oxide, silicon nitride, and silicon oxynitride; or lithium titanate (LTO) material, such as silicate glass; the spin-coated carbon material includes: at least one of silicon oxide, silicon nitride, and silicon oxynitride.

[0072] The metal gate material includes at least one of chromium oxide, thallium chloride, titanium chloride and titanium nitride.

[0073] S14: depositing a metal gate material in the remaining area of ​​the metal gate trench to form a metal gate structure.

[0074] like Fig.10a , Fig.10b As shown, a metal gate material 410 is deposited in the remaining area of ​​the metal gate trench 200 to form a metal gate structure 400 .

[0075] The metal gate structure 400 manufactured by the method for forming a semiconductor device provided in this embodiment first forms a metal gate groove 200 on a substrate 100, then forms a cutting groove 300, and fills the cutting groove 300 with an isolation material 310 to form an isolation structure, and finally fills the metal gate groove 200 with a metal gate material 410 to form a metal gate structure 400.

[0076] This method effectively avoids the problem in the prior art that a metal gate structure 400 is first formed on a substrate 100 and then the metal gate structure 400 is etched to form a cutting groove 300, but the metal gate structure 400 is relatively hard and difficult to etch, making it difficult to form the required isolation structure; or, the substrate 100 is first etched to form an isolation structure and then the metal gate structure 400 is formed, but there will be residues of the substrate 100 material on both sides of the metal gate structure 400, which affects the performance of the metal gate structure 400 and further causes the problem of poor performance of the semiconductor device.

[0077] In addition, the metal gate material 410 may include at least one of chromium oxide, thallium chloride, titanium chloride, and titanium nitride, and may not be limited to the materials given in this embodiment. The specific selection can be based on actual needs, and this embodiment does not make any specific limitations on this.

[0078] The method for forming a semiconductor device provided in this embodiment includes the following steps: providing a substrate and forming a metal gate groove on one side of the substrate; cutting the metal gate groove along the width extension direction of the metal gate groove to form a cutting groove; depositing an isolation material in the projection area of ​​the overlapping part of the metal gate groove and the cutting groove in the metal gate groove to form an isolation structure; and depositing a metal gate material in the remaining area of ​​the metal gate groove to form a metal gate structure.

[0079] The method for forming a semiconductor device provided by the present invention effectively avoids the problem in the prior art that a metal gate is first formed on a substrate and then the metal gate is etched to form a cutting groove, but the metal gate is relatively hard and difficult to etch, making it difficult to form an isolation structure; or, the substrate is first etched to form an isolation structure and then the metal gate is formed, and there will be substrate residues on both sides of the metal gate, resulting in poor performance of the metal gate of the semiconductor device.

[0080] This embodiment also provides a semiconductor device, which is manufactured based on the semiconductor device method described above. The specific manufacturing method process is briefly described as follows:

[0081] like Figure 2a , Figure 2b As shown, a gate fin 110 is formed on one side of the substrate 100 , a dummy gate 120 is formed across the gate fin 110 , and a first gate oxide film layer 130 is deposited at the position where the gate fin 110 contacts the dummy gate 120 ; an interlayer dielectric layer 140 is deposited around the dummy gate 120 .

[0082] like Figure 3a , Figure 3b As shown, the dummy gate 120 is removed to form a metal gate trench 200. At this time, a gate dielectric layer 230 and a second gate oxide film layer 210 are deposited on the inner wall of the metal gate trench 200.

[0083] like Figure 4a , Figure 4b As shown, a second gate oxide film layer 210 and a work function metal layer 220 are sequentially deposited on the inner side of the metal gate trench 200, wherein a gate dielectric layer 230 is deposited on the inner wall of the metal gate trench 200, and the second gate oxide film layer 210 is in contact with the gate dielectric layer 230 and the work function metal layer 220 respectively; and the work function metal layer 220 is also deposited on the side of the interlayer dielectric layer 140 away from the substrate 100.

[0084] like Figure 5a , Figure 5b As shown, a spin-on carbon material 240 is deposited in the metal gate trench 200 and on a side of the work function metal layer 220 deposited on a side of the interlayer dielectric layer 140 away from the substrate 100 away from the substrate 100 .

[0085] like Figure 6a , Figure 6b As shown, the spin-coated carbon material 240 is etched according to the cutting groove pattern along the width extension direction of the metal gate groove 200, the spin-coated carbon material 240 corresponding to the cutting groove pattern in the metal gate groove 200 is removed, the spin-coated carbon material 240 corresponding to the cutting groove pattern deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 is removed, and part of the interlayer dielectric layer 140 corresponding to the cutting groove pattern is removed to form a cutting groove 300.

[0086] Furthermore, the second gate oxide film layer 210 and the work function metal layer 220 on the side of the metal gate trench 200 close to the substrate 100 are removed.

[0087] like Figure 7a , Figure 7b As shown, when the spin-on carbon material 240 is removed, the work function metal layer 220 deposited on the inner wall and sidewall of the metal gate trench 200 in the projection area where the metal gate trench 200 overlaps the cutting trench 300 is also included. .

[0088] like Figure 8a , Figure 8b As shown, an isolation material 310 is deposited in the projection area of ​​the metal gate trench 200 where the metal gate trench 200 overlaps with the cutting trench 300 , and an isolation material 310 is deposited in the remaining area of ​​the cutting trench 300 .

[0089] like Figure 9a , Figure 9b As shown, the isolation material 310 filled in the cutting trench 300 is etched to form a cutting trench opening 320. The remaining area of ​​the metal gate trench 200 and the spin-on carbon material 240 deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 are removed.

[0090] like Figure 9a , Figure 9b As shown, before depositing the metal gate material, the process also includes: removing the remaining area of ​​the metal gate trench 200 , and removing the spin-on carbon material 240 deposited on the side of the work function metal layer 220 deposited on the side of the interlayer dielectric layer 140 away from the substrate 100 .

[0091] like Fig.10a , Fig.10bAs shown, a metal gate material 410 is deposited in the remaining area of ​​the metal gate trench 200 to form a metal gate structure 400 .

[0092] The semiconductor device provided in this embodiment effectively avoids the problem in the prior art that, in the manufacturing process of the semiconductor device, a metal gate is first formed on a substrate and then the metal gate is etched to form a cutting groove, while the metal gate is relatively hard and difficult to etch, making it difficult to form an isolation structure; or, the substrate is first etched to form an isolation structure and then the metal gate is formed, and there will be substrate residues on both sides of the metal gate, resulting in poor performance of the metal gate of the semiconductor device.

[0093] The above contents are further detailed descriptions of the present invention in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the scope of protection of the present invention. And it can reduce costs.

Claims

1. A method for forming a semiconductor device, characterized in that: The following steps are involved: Providing a substrate, and forming a metal gate trench on one side of the substrate; Cutting the metal gate trench along a width extension direction of the metal gate trench to form a cutting trench; Depositing an isolation material in a projection area of ​​an overlapping portion of the metal gate trench and the cutting trench in the metal gate trench to form an isolation structure, and depositing an isolation material in the remaining area of ​​the cutting trench; Etching and removing a portion of the isolation material filled in the cutting groove to form a cutting groove opening, wherein the shape of the cutting groove opening is a shuttle shape, and S1 ≥ S2, wherein S1 is the distance from the edge area of ​​the end surface of the cutting groove opening to the substrate, and S2 is the distance from the middle area of ​​the end surface of the cutting groove opening to the substrate; A metal gate material is deposited in the remaining area of ​​the metal gate trench to form a metal gate structure.

2. The method for forming a semiconductor device according to claim 1, wherein: Forming a metal gate trench on one side of the substrate comprises the following steps: forming a gate fin on the one side of the substrate, forming a dummy gate across the gate fin, and depositing a first gate oxide film layer at a position where the gate fin contacts the dummy gate; Depositing an interlayer dielectric layer around the dummy gate; The dummy gate is removed to form the metal gate trench.

3. The method for forming a semiconductor device according to claim 2, wherein: After forming the metal gate trench, the method further includes: depositing a second gate oxide film layer and a work function metal layer in sequence on the inner side of the metal gate trench, wherein a gate dielectric layer is also deposited on the inner wall of the metal gate trench, and the second gate oxide film layer is in contact with the gate dielectric layer and the work function metal layer respectively; and The work function metal layer is also deposited on a side of the interlayer dielectric layer away from the substrate.

4. The method for forming a semiconductor device according to claim 3, wherein: Also includes: Depositing a spin-on carbon material on a side of the work function metal layer away from the substrate; The spin-coated carbon material is etched according to the cutting groove pattern along the width extension direction of the metal gate groove, the spin-coated carbon material corresponding to the cutting groove pattern in the metal gate groove is removed, the spin-coated carbon material corresponding to the cutting groove pattern deposited on the side of the interlayer dielectric layer away from the substrate is removed, and a portion of the interlayer dielectric layer corresponding to the cutting groove pattern is removed to form the cutting groove.

5. The method for forming a semiconductor device according to claim 4, wherein: When removing the spin-on carbon material, the method further includes: removing the second gate oxide film layer and the work function metal layer in the metal gate trench close to the substrate.

6. The method for forming a semiconductor device according to claim 4, wherein: Before depositing the metal gate material, the method further includes: The remaining area of ​​the metal gate trench and the spin-on carbon material deposited on the side of the work function metal layer deposited on the side of the interlayer dielectric layer away from the substrate are removed.

7. The method for forming a semiconductor device according to claim 4, wherein: The isolation material includes at least one of silicon oxide, silicon nitride, silicon oxynitride, and silicate glass.

8. A semiconductor device, characterized in that: The semiconductor device is manufactured based on the method for forming a semiconductor device according to any one of claims 1 to 7.

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