Patterning method and semiconductor device formed therefrom

Abstract

A patterning method and a semiconductor device formed by the same, the method comprising: providing a layer to be etched; forming a first mask layer on the layer to be etched; forming a plurality of first grooves that are mutually discrete and arranged in parallel along a first direction in the first mask layer; forming a filling layer in the first groove, the filling layer filling the first groove; etching and removing part of the first mask layer and part of the filling layer, forming a plurality of second grooves that are mutually discrete and arranged in parallel along the first direction between adjacent first grooves, the second grooves exposing the sidewalls of the filling layer; forming an isolation sidewall on the sidewalls of the second grooves, so that the second grooves are formed into second grooves; removing the filling layer, and forming the first grooves in the first mask layer. The reliability of the patterning method is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing, and in particular to a patterning method and a semiconductor device formed therefrom. Background Art

[0002] In the process of manufacturing semiconductor devices, the pattern on the mask is usually transferred to the substrate by using a photolithography process. The photolithography process includes: providing a substrate; forming a pattern on the substrate; exposing and developing the pattern to form a patterned pattern so that the pattern on the mask is transferred to the pattern; etching the substrate using the patterned pattern as a mask so that the pattern on the pattern is transferred to the substrate; removing the pattern.

[0003] As the size of semiconductor devices continues to shrink, the critical dimensions of lithography are gradually approaching or even exceeding the physical limits of lithography, which poses a more severe challenge to lithography technology. The basic idea of ​​double patterning technology is to form the final target pattern through two patternings to overcome the lithography limit that cannot be achieved by single patterning.

[0004] However, the reliability of existing patterning processes is poor. Summary of the invention

[0005] The problem solved by the present invention is to provide a patterning method and a semiconductor device formed therefrom, so as to improve the reliability of the patterning method.

[0006] To solve the above problems, the present invention provides a graphical method, including: providing a layer to be etched; forming a first mask layer on the layer to be etched; forming a plurality of first grooves that are separate from each other and arranged in parallel along a first direction in the first mask layer; forming a filling layer in the first groove, wherein the filling layer fills the first groove; etching and removing part of the first mask layer and part of the filling layer, forming a plurality of second grooves that are separate from each other and arranged in parallel along the first direction between adjacent first grooves, wherein the second grooves expose the side walls of the filling layer; forming isolation sidewalls on the side walls of the second grooves, so that the second grooves are formed into second grooves; removing the filling layer, and forming the first grooves in the first mask layer.

[0007] Optionally, the material of the isolation sidewall includes: silicon oxide, silicon nitride, titanium oxide, titanium nitride, aluminum nitride or aluminum oxide.

[0008] Optionally, the thickness of the isolation sidewall is 5nm to 30nm.

[0009] Optionally, the material of the filling layer includes carbon-containing organic material.

[0010] Optionally, the method for forming the filling layer includes: forming an initial filling layer in the first groove and on the first mask layer, wherein the initial filling layer fills the first groove; and etching back the initial filling layer until the surface of the first mask layer is exposed to form the filling layer.

[0011] Optionally, the method for forming the first groove includes: forming a first patterned layer on a first mask layer, the first patterned layer having a plurality of discrete first photolithography openings arranged along a first direction, the first photolithography openings exposing a portion of the surface of the first mask layer; using the first patterned layer as a mask, etching the first mask layer to form a first groove in the first mask layer.

[0012] Optionally, the method for forming the second groove includes: forming a first barrier layer on the first mask layer and the filling layer, the first barrier layer having a plurality of discrete first openings arranged along a first direction, the first openings exposing a portion of the filling layer and a portion of the surface of the first mask layer; after forming the first barrier layer, using the first barrier layer as a mask, etching away the first mask layer and the filling layer exposed by the first openings, and forming a plurality of second grooves that are discrete from each other and arranged parallel to the first direction between adjacent first grooves; after etching away a portion of the first mask layer and a portion of the filling layer, removing the first barrier layer.

[0013] Optionally, the method for forming the first barrier layer includes: forming an initial first barrier layer on a first mask layer and a filling layer; forming a second patterned layer on the initial first barrier layer, the second patterned layer having a plurality of discrete second photolithography openings arranged along a first direction, the second photolithography openings exposing a portion of the surface of the initial first barrier layer; etching the initial first barrier layer using the second patterned layer as a mask until a portion of the filling layer and a portion of the surface of the first mask layer are exposed, so that the initial first barrier layer forms a first barrier layer; after etching the initial first barrier layer using the first patterned layer as a mask, removing the second patterned layer.

[0014] Optionally, the material of the first barrier layer includes: one or more of a bottom anti-reflective coating material, an organic planarization layer material or a spin-coated carbon material.

[0015] Optionally, after forming the filling layer and before forming the first barrier layer, a first stop layer is formed on the first mask layer and the filling layer; the first opening exposes a portion of the filling layer and a portion of the surface of the first stop layer on the first mask layer.

[0016] Optionally, a material of the first stop layer includes silicon oxide, silicon nitride, titanium oxide, titanium nitride, aluminum nitride or aluminum oxide.

[0017] Optionally, the method for forming the isolation sidewall includes: forming an initial isolation sidewall material layer on the bottom and sidewall of the second groove, on the filling layer and on the first mask layer; and etching back the initial isolation sidewall material layer until the surface of the first mask layer and the filling layer are exposed to form the isolation sidewall.

[0018] Optionally, the process of forming the initial isolation spacer material layer includes: one or more of a chemical vapor deposition process, a physical vapor deposition process or an atomic layer deposition process.

[0019] Optionally, the process of etching and removing the filling layer has a first etching rate for the isolation sidewalls and a second etching rate for the filling layer, and a ratio of the first etching rate to the second etching rate is 1:50 to 1:100.

[0020] Optionally, it also includes: after forming the first groove and the second groove, etching the layer to be etched at the bottom of the first groove to form a first target groove in the layer to be etched; etching the layer to be etched at the bottom of the second groove to form a second target groove in the layer to be etched; forming a first interconnection layer in the first target groove; and forming a second interconnection layer in the second target groove.

[0021] Optionally, the filling layer covers the surface of the first mask layer.

[0022] The present invention also provides a semiconductor device formed by adopting any one of the above methods.

[0023] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0024] In the patterning method provided by the technical solution of the present invention, after the isolation side wall is formed, no patterning process is required during the formation of the first groove. The shape of the isolation side wall is regular, and the layer to be etched is subsequently etched to form the first target groove and the second target groove. The distance between the first target groove and the second target groove is stable, thereby improving the reliability of the patterning method. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figures 1 to 4 It is a schematic diagram of the structure during the process of a graphical method;

[0026] Figures 5 to 23 It is a structural schematic diagram of the process of performing a graphical method in one embodiment of the present invention. DETAILED DESCRIPTION

[0027] As described in the background art, existing graphical methods have poor reliability.

[0028] Figures 1 to 4 It is a structural schematic diagram of the process of forming a semiconductor device.

[0029] refer to Figure 1, providing a substrate 100, wherein the substrate 100 includes a plurality of discrete first areas A01 and a plurality of discrete second areas A02, wherein the first areas A01 and the second areas A02 are alternately arranged along a first direction X, and adjacent first areas A01 and second areas A02 are adjacent to each other.

[0030] refer to Figure 2 , forming a first initial mask layer 110 on the first area A01 and the second area A02 of the substrate 100 ; removing a portion of the first initial mask layer 110 in the first area A01 , and providing a plurality of discrete first grooves 120 in the first initial mask layer 110 .

[0031] refer to Figure 3 After the first trench 120 is formed, a mask spacer 130 is formed on the sidewall of the first trench 120 , so that the first trench 120 is formed into a first groove 140 .

[0032] refer to Figure 4 After the mask spacer 130 is formed, a discrete second groove 150 is formed in the first initial mask layer 110 in the second area A02 , and the sidewall of the second groove 150 exposes the mask spacer 130 .

[0033] In the above embodiment, the second groove 150 is formed by forming a patterned layer in the first groove 140, on the mask sidewall 130 and on the first initial mask layer 110, wherein the patterned layer exposes a portion of the surface of the first initial mask layer 110 in the second area A02; and removing a portion of the first initial mask layer 110 by etching using the patterned layer as a mask to form the second groove 150. To ensure that the sidewall of the second groove 150 exposes the mask sidewall 130, the patterned layer also exposes the top surface of the mask sidewall 130, and thus, during the etching process of the first initial mask layer 110, the mask sidewall 130 is damaged, resulting in poor reliability of the patterning process.

[0034] On this basis, the present invention provides a patterning method, providing a layer to be etched, forming a first mask layer on the layer to be etched; forming a first groove in the first mask layer; forming a filling layer in the first groove; etching and removing part of the first mask layer and part of the filling layer to form a second groove; forming an isolation sidewall on the sidewall of the second groove; removing the filling layer to form a first groove in the first mask layer. The material of the filling layer is reasonably selected, and when removing the filling layer, the selection ratio of etching the filling layer is relatively large relative to the selection ratio of the isolation sidewall and the first mask layer, the damage to the isolation sidewall is small, the shape of the isolation sidewall is regular, and the layer to be etched is subsequently etched to form a first target groove and a second target groove. The distance between the first target groove and the second target groove is stable, which improves the reliability of the patterning method.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0036] Figures 5 to 23 It is a structural schematic diagram of the process of performing a graphical method in one embodiment of the present invention.

[0037] refer to Figure 5 , providing a layer 200 to be etched.

[0038] The layer to be etched 200 may be a single material layer or a multi-layer stacked material layer, and may specifically include a dielectric material, a metal material, or a hard mask material.

[0039] The material of the layer to be etched 200 includes silicon oxide or a low-K dielectric layer (K ​​is less than or equal to 3.9).

[0040] In this embodiment, the layer to be etched 200 is a multi-layer stacked material layer, including: a first material layer (not shown in the figure) and a second material layer (not shown in the figure) located on the surface of the first material layer.

[0041] The material of the first material layer includes: low-K dielectric material (K is less than or equal to 3.9); the material of the second material layer includes: silicon oxide, silicon nitride or silicon oxynitride.

[0042] The functions of the second material layer include: the second material layer serves as an etching stop layer; the material of the second material layer is a hard mask material, so in the subsequent etching process, the second material layer is subjected to less etching loss, and in the process of transferring the pattern in the second material layer to the layer to be etched, the stability of the pattern transfer is higher.

[0043] refer to Figure 6 and Figure 7 , Figure 6 for Figure 5 Based on the schematic diagram, Figure 7 for Figure 6 A cross-sectional view of the middle cutting line MN; a first mask layer 210 is formed on the layer to be etched 200.

[0044] The first mask layer 210 provides a mask layer for subsequently forming a first target groove and a second target groove.

[0045] In this embodiment, the method further includes: before forming the first mask layer 210 , forming an underlying hard mask layer on the layer to be etched 200 ; after forming the underlying hard mask layer, forming the first mask layer 210 on the underlying hard mask layer.

[0046] In this embodiment, the bottom hard mask layer contacts the layer to be etched 200 , and the first mask layer 210 contacts the bottom hard mask layer.

[0047] The material of the bottom hard mask layer includes titanium nitride.

[0048] The material of the first mask layer 210 includes polysilicon, silicon dioxide, silicon nitride, titanium oxide or titanium nitride.

[0049] In this embodiment, the materials used for the first mask layer 210 are all hard mask materials.

[0050] In this embodiment, the material of the first mask layer 210 is polysilicon.

[0051] The functions of the bottom hard mask layer include: the bottom hard mask layer serves as an etching stop layer; the bottom hard mask layer serves as a stop layer for the subsequent planarization of the interconnect film; the bottom mask layer is made of a hard mask material, so when the first mask layer 210 is subsequently etched to form the first groove and the second groove, the etching loss of the bottom mask layer is small, and in the process of transferring the pattern in the bottom mask layer to the layer to be etched 200, the stability of the pattern transfer is high.

[0052] In this embodiment, the materials of the bottom hard mask layer and the first mask layer 210 are different from each other.

[0053] Next, a plurality of discrete first grooves arranged along the first direction X are formed in the first mask layer 210 .

[0054] A first patterned layer 220 is formed on the surface of the first mask layer 210 . The first patterned layer 220 has a plurality of first photolithography openings 201 which are separated from each other and arranged in parallel along the first direction X. The first photolithography openings 201 expose a portion of the surface of the first mask layer 210 .

[0055] The first patterned layer 220 provides a mask layer for subsequently forming a first groove.

[0056] The material of the first patterned layer 220 is photoresist.

[0057] refer to Figure 8 and Fig. 9 , Figure 8 for Figure 6 Based on the schematic diagram, Fig. 9 for Figure 8 The first patterned layer 220 is used as a mask to etch the first mask layer 210, and a plurality of first grooves 211 which are separated from each other and arranged in parallel along the first direction X are formed in the first mask layer 210.

[0058] The first groove 211 penetrates the first mask layer 210 .

[0059] The first groove 211 provides space for subsequently forming a first groove.

[0060] The process of etching the first mask layer 210 includes: an anisotropic dry etching process or an anisotropic wet etching process.

[0061] In this embodiment, the process of etching the first mask layer 210 is an anisotropic dry etching process.

[0062] In this embodiment, the first patterned layer 220 is removed after etching the first mask layer 210 .

[0063] The process of removing the first patterned layer 220 is a dry etching process.

[0064] In one embodiment, the method for forming the first groove includes: forming a second barrier layer on the first mask layer, the second barrier layer having a second opening, the second opening exposing a portion of the surface of the first mask layer; after forming the second barrier layer, using the second barrier layer as a mask, etching away a portion of the first mask layer to form the first groove in the first mask layer; after etching away a portion of the first mask layer, removing the second barrier layer.

[0065] The method for forming the second barrier layer includes: forming an initial second barrier layer on a first mask layer; forming a photoresist layer on the initial second barrier layer, wherein the photoresist layer exposes a portion of the surface of the initial second barrier layer; etching the initial second barrier layer using the photoresist layer as a mask until a portion of the surface of the first mask layer is reached, so that the initial second barrier layer forms a second barrier layer; after etching the initial second barrier layer using the photoresist layer as a mask, removing the photoresist layer.

[0066] The material of the second barrier layer includes: one or more of a bottom anti-reflection coating material, an organic planarization layer material or a spin-coated carbon material.

[0067] refer to Fig.10 and Fig.11 , Fig.10 for Figure 8 Based on the schematic diagram, Fig.11 for Fig.10 A filling layer 230 is formed in the first groove 211, and the filling layer 230 fills the first groove 211.

[0068] In this embodiment, the top surface of the filling layer 230 is flush with the top surface of the first mask layer 210 .

[0069] The method for forming the filling layer 230 includes: forming an initial filling layer (not shown) in the first groove 211 and on the first mask layer 210, wherein the initial filling layer fills the first groove 211; and etching back the initial filling layer until the surface of the first mask layer 210 is exposed to form the filling layer 230.

[0070] The process of forming the initial filling layer includes: a chemical vapor deposition process or a spin coating process.

[0071] The material of the filling layer 230 includes carbon-containing organic material.

[0072] In this embodiment, the initial filling layer is formed by a spin coating process.

[0073] In one embodiment, reference Fig.12 , Fig.12 for Fig. 9 Based on the schematic diagram, a filling layer 230 is formed in the first groove 211, and the filling layer 230 fills the first groove 211. The filling layer 230 covers the surface of the first mask layer 210, and the top surface of the filling layer 230 is higher than the top surface of the first mask layer 210.

[0074] Next, a portion of the first mask layer and a portion of the filling layer are removed by etching to form a plurality of discrete second grooves arranged along the first direction.

[0075] The method for forming the second groove comprises: forming a first barrier layer on the first mask layer and the filling layer, wherein the first barrier layer has a plurality of discrete first openings arranged along a first direction X, wherein the first openings expose a portion of the filling layer and a portion of the surface of the first mask layer; after forming the first barrier layer, using the first barrier layer as a mask, etching away a portion of the first mask layer and a portion of the filling layer, and forming the second groove in the first mask layer. For the method for forming the second groove, please refer to Figures 13 to 18 .

[0076] refer to Fig.13 and Fig.14 , Fig.13 for Fig.10 Based on the schematic diagram, Fig.14 for Fig.13 A cross-sectional view of the middle cutting line MN; an initial first barrier layer 240 is formed on the first mask layer 210 and the filling layer 230; a second patterned layer 204 is formed on the initial first barrier layer 240, and the second patterned layer 204 has a plurality of second photolithography openings 203 that are separate from each other and arranged in parallel along the first direction X, and the second photolithography openings 203 expose a portion of the surface of the initial first barrier layer 240.

[0077] The second patterned layer 204 provides a mask layer for forming the first barrier layer.

[0078] The material of the second patterned layer 204 is photoresist.

[0079] In this embodiment, after forming the filling layer 230 and before forming the initial first barrier layer 240 , a first stop layer 202 is formed on the first mask layer 210 and the filling layer 230 .

[0080] The first stop layer 202 is a stop layer for subsequently etching the initial first barrier layer.

[0081] The material of the first stop layer 202 includes silicon oxide, silicon nitride, titanium oxide, titanium nitride, aluminum nitride or aluminum oxide.

[0082] In this embodiment, the material of the first stop layer 202 is titanium oxide.

[0083] The material of the first stop layer 202 is different from the material of the initial first barrier layer.

[0084] The process of forming the initial first barrier layer 240 includes: a chemical vapor deposition process or a spin coating process.

[0085] In this embodiment, the process of forming the initial first barrier layer 240 is a spin coating process.

[0086] The initial first barrier layer 240 may be a single-layer structure or a multi-layer structure.

[0087] The second photolithography opening 203 exposes a portion of the filling layer 230 and a portion of the surface of the initial first barrier layer 240 on the first mask layer 210 .

[0088] In this embodiment, the second photolithography opening 203 exposes a portion of the filling layer 230 and a surface of the initial first barrier layer 240 on the first mask layer 210 located between adjacent filling layers 230 .

[0089] In one embodiment, the filling layer covers the first mask layer, and the first stop layer covers the surface of the filling layer.

[0090] refer to Fig.15 and Fig.16 , Fig.15 for Fig.13 Based on the schematic diagram, Fig.16 for Fig.15 A cross-sectional view of the middle cutting line MN; the initial first barrier layer 240 is etched using the second patterned layer 204 as a mask until a portion of the filling layer 230 and a portion of the surface of the first mask layer 210 are exposed, so that the initial first barrier layer 240 forms a first barrier layer 241, and the first barrier layer 241 has a plurality of first openings 212 that are separate from each other and arranged in parallel along the first direction X.

[0091] The first barrier layer 241 provides a mask layer for subsequently forming a second trench.

[0092] The material of the first barrier layer 241 includes: one or more of a bottom anti-reflection coating material, an organic planarization layer material, or a spin-on carbon material.

[0093] In this embodiment, the material of the first barrier layer 241 is a bottom anti-reflection coating material.

[0094] The first barrier layer 241 may be a single-layer structure or a multi-layer structure. When the first barrier layer 241 is a multi-layer structure, the materials of each layer are different.

[0095] The material of the first barrier layer 241 is different from the materials of the first mask layer 210 and the filling layer 230, which can ensure that when a portion of the first mask layer 210 and the filling layer 230 are etched away, the etching loss of the first barrier layer 230 is small and the stability of the pattern transfer is high.

[0096] In this embodiment, the first opening 212 exposes a portion of the surface of the first stop layer 212 on the filling layer and a portion of the first mask layer.

[0097] In this embodiment, the method further includes removing the second patterned layer 204 after etching the initial first barrier layer 240 using the second patterned layer as a mask.

[0098] The process of removing the second patterned layer 204 is a dry etching process.

[0099] refer to Fig.17 and Fig.18 , Fig.17 for Fig.15 Based on the schematic diagram, Fig.18 for Fig.17 A cross-sectional view of the middle cutting line MN; after forming the first barrier layer 241, the first barrier layer 241 is used as a mask to etch away the first mask layer 210 and the filling layer 230 exposed by the first opening 212, and a plurality of second grooves 205 separated from each other and arranged in parallel along the first direction X are formed between adjacent first grooves.

[0100] The second groove 205 penetrates the first mask layer 210 .

[0101] The second groove 205 provides space for subsequently forming a second recess, and the second groove 205 defines the position and shape of the subsequently formed isolation sidewall.

[0102] In this embodiment, before etching away a portion of the first mask layer 210 and a portion of the filling layer 230 , the process further includes: removing the first stop layer 202 exposed at the bottom of the first opening 212 .

[0103] In one embodiment, after forming the first barrier layer, the first barrier layer is used as a mask to etch away the first stop layer exposed by the first opening and the filling layer and the first mask layer at the bottom of the first stop layer to form a second groove.

[0104] The process of etching and removing a portion of the first mask layer 210 and a portion of the filling layer 230 includes an anisotropic dry etching process.

[0105] The material of the first barrier layer 241 is different from that of the first mask layer 210, and the material of the first barrier layer 241 is also different from that of the filling layer 230. Selecting etching parameters with a faster etching speed for the first mask layer 210 and the filling layer 230 and a slower etching speed for the first barrier layer 241 can ensure that on the basis of etching away a portion of the first mask layer 210 and a portion of the filling layer 230, the first barrier layer 241 is less damaged and the pattern transfer is more stable.

[0106] In this embodiment, the first barrier layer 241 is removed after a portion of the first mask layer 210 and a portion of the filling layer 230 are removed by etching.

[0107] The process of removing the first barrier layer 241 is a dry etching process.

[0108] Next, an isolation sidewall is formed on the sidewall of the second trench 205. The method for forming the isolation sidewall can be found in Figures 19 to 21 .

[0109] refer to Fig.19 , Fig.19 for Fig.18 Based on the schematic diagram of FIG. 1 , an initial isolation spacer material layer 206 is formed on the bottom and sidewall of the second trench 205 , on the filling layer 230 and on the first mask layer 210 .

[0110] The initial isolation spacer material layer 206 provides a material layer for subsequently forming an isolation spacer.

[0111] In this embodiment, an initial isolation spacer material layer 206 is formed on the bottom and sidewall of the second groove 205 and on the first stop layer 202 .

[0112] The process of forming the initial isolation spacer material layer 206 includes: one or more of a chemical vapor deposition process, a physical vapor deposition process or an atomic layer deposition process.

[0113] The material of the initial isolation spacer material layer 206 includes silicon oxide, silicon nitride, titanium oxide, titanium nitride, aluminum nitride or aluminum oxide.

[0114] refer to Fig. 20 and Fig.21 , Fig. 20 for Fig.17 Based on the schematic diagram, Fig.21 for Fig. 20The initial isolation spacer material layer 206 is etched back until the surface of the first mask layer 210 and the filling layer 230 are exposed to form the isolation spacer 250, and the second groove 205 is formed into a second groove 215.

[0115] In this embodiment, the initial isolation spacer material layer and the first stop layer 202 are etched back until the surfaces of the first mask layer 210 and the filling layer 230 are exposed to form the isolation spacer 250 .

[0116] In one embodiment, the initial isolation spacer material layer and the first stop layer are etched back until the surface of the filling layer is exposed to form the isolation spacer.

[0117] The isolation spacer 250 is formed by etching back the initial isolation spacer material layer 206 , so the material of the isolation spacer 250 includes: silicon oxide, silicon nitride, titanium oxide, titanium nitride, aluminum nitride or aluminum oxide.

[0118] In this embodiment, the material of the isolation sidewall 250 is titanium oxide.

[0119] The thickness of the isolation sidewall 250 is 5 nm to 30 nm.

[0120] If the thickness of the isolation sidewall 250 is greater than 30nm, the area of ​​the second groove 215 is small, the resistance of the second interconnection layer formed subsequently is large, and the performance of the semiconductor device is poor. If the thickness of the isolation sidewall 250 is less than 5nm, the isolation effect between the first interconnection layer and the second interconnection layer formed subsequently is poor.

[0121] refer to Fig. 22 and Fig.23 , Fig. 22 for Fig. 20 Based on the schematic diagram, Fig.23 for Fig. 22 The filling layer 230 is removed, and a first groove 221 is formed in the first mask layer 210.

[0122] The process of removing the filling layer 230 includes: a dry etching process or a wet etching process.

[0123] In this embodiment, the process for removing the filling layer 230 is an ashing process. The ashing process is used to remove the filling layer 230, which is simple and easy to implement.

[0124] The process of etching and removing the filling layer 230 has a first etching rate for the isolation sidewall 250 and a second etching rate for the filling layer 230 , and the ratio of the first etching rate to the second etching rate is 1:50 to 1:100.

[0125] After forming the isolation sidewall 250, the patterning process is not required in the process of forming the first groove 221. The material of the filling layer 230 is reasonably selected. When removing the filling layer 230, the selection ratio of etching the filling layer 230 is relatively large compared with the selection of the isolation sidewall 250 and the first mask layer 210, and the damage to the isolation sidewall 250 is small. The shape of the isolation sidewall 250 is regular, and the etched layer 200 is subsequently etched to form the first target groove and the second target groove. The distance between the first target groove and the second target groove is stable, which improves the reliability of the patterning method. At the same time, the selection range of the filling layer 230 material is relatively large, and the selection range of the first mask layer 210 and the isolation sidewall 250 material is also relatively large. The process parameter can be adjusted in a wide range, which is conducive to the improvement of the process capability.

[0126] The patterning method also includes: after forming the first groove and the second groove, etching the layer to be etched 200 at the bottom of the first groove to form a first target groove in the layer to be etched 200; etching the layer to be etched 200 at the bottom of the second groove to form a second target groove in the layer to be etched 200; forming a first interconnection layer in the first target groove; and forming a second interconnection layer in the second target groove.

[0127] Correspondingly, this embodiment also provides a semiconductor device formed by adopting the above method.

[0128] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A graphical method, characterized in that: include: Providing a layer to be etched; forming a first mask layer on the layer to be etched; forming a plurality of first grooves separated from each other and arranged in parallel along a first direction in the first mask layer; forming a filling layer in the first groove, wherein the filling layer completely fills the first groove; Etching and removing a portion of the first mask layer and a portion of the filling layer to form a plurality of second grooves separated from each other and arranged in parallel along the first direction between adjacent first grooves, wherein the second grooves expose side walls of the filling layer; forming an isolation sidewall on a sidewall of the second groove so that the second groove is formed into a second recess; The filling layer is removed to form a first groove in the first mask layer. When removing the filling layer, the selectivity of etching the filling layer is greater than the selectivity of etching the isolation sidewall and the first mask layer.

2. The graphical method according to claim 1, characterized in that: The material of the isolation sidewalls includes silicon oxide, silicon nitride, titanium oxide, titanium nitride, aluminum nitride or aluminum oxide.

3. The graphical method according to claim 1, characterized in that: The thickness of the isolation sidewall is 5nm~30nm.

4. The graphical method according to claim 1, characterized in that: The material of the filling layer includes carbon-containing organic material.

5. The graphical method according to claim 1, characterized in that: The method for forming the filling layer comprises: forming an initial filling layer in the first groove and on the first mask layer, wherein the initial filling layer fills the first groove; and etching back the initial filling layer until the surface of the first mask layer is exposed to form the filling layer.

6. The graphical method according to claim 1, characterized in that: The method for forming the first groove includes: forming a first patterned layer on a first mask layer, the first patterned layer having a plurality of discrete first photolithography openings arranged along a first direction, the first photolithography openings exposing a portion of the surface of the first mask layer; using the first patterned layer as a mask, etching the first mask layer to form a first groove in the first mask layer.

7. The graphical method according to claim 1, characterized in that: The method for forming the second groove includes: forming a first barrier layer on the first mask layer and the filling layer, the first barrier layer having a plurality of discrete first openings arranged along a first direction, the first openings exposing a portion of the filling layer and a portion of the surface of the first mask layer; after forming the first barrier layer, using the first barrier layer as a mask, etching away the first mask layer and the filling layer exposed by the first openings, and forming a plurality of second grooves that are discrete from each other and arranged parallel to the first direction between adjacent first grooves; after etching away a portion of the first mask layer and a portion of the filling layer, removing the first barrier layer.

8. The graphical method according to claim 7, characterized in that: The method for forming the first barrier layer includes: forming an initial first barrier layer on a first mask layer and a filling layer; forming a second patterned layer on the initial first barrier layer, wherein the second patterned layer has a plurality of discrete second photolithography openings arranged along a first direction, and the second photolithography openings expose a portion of the surface of the initial first barrier layer; etching the initial first barrier layer using the second patterned layer as a mask until a portion of the filling layer and a portion of the surface of the first mask layer are exposed, so that the initial first barrier layer forms a first barrier layer; after etching the initial first barrier layer using the first patterned layer as a mask, removing the second patterned layer.

9. The graphical method according to claim 7, characterized in that: The material of the first barrier layer includes: one or more of a bottom anti-reflection coating material, an organic planarization layer material or a spin-coated carbon material.

10. The graphical method according to claim 8, characterized in that: After forming the filling layer and before forming the first barrier layer, a first stop layer is formed on the first mask layer and the filling layer; the first opening exposes a portion of the filling layer and a portion of the surface of the first stop layer on the first mask layer.

11. The graphical method according to claim 10, characterized in that: The material of the first stop layer includes silicon oxide, silicon nitride, titanium oxide, titanium nitride, aluminum nitride or aluminum oxide.

12. The graphical method according to claim 1, characterized in that: The method for forming the isolation sidewall comprises: forming an initial isolation sidewall material layer on the bottom and sidewall of the second groove, on the filling layer and on the first mask layer; etching back the initial isolation sidewall material layer until the surface of the first mask layer and the filling layer are exposed to form the isolation sidewall.

13. The graphical method according to claim 12, characterized in that: The process of forming the initial isolation spacer material layer includes: one or more of a chemical vapor deposition process, a physical vapor deposition process or an atomic layer deposition process.

14. The graphical method according to claim 1, characterized in that: The process of etching and removing the filling layer has a first etching rate for the isolation sidewall and a second etching rate for the filling layer, and the ratio of the first etching rate to the second etching rate is 1:50-1:

100.

15. The graphical method according to claim 1, characterized in that: Also includes: After forming the first groove and the second groove, etching the layer to be etched at the bottom of the first groove to form a first target groove in the layer to be etched; Etching the layer to be etched at the bottom of the second groove to form a second target groove in the layer to be etched; A first interconnect layer is formed in the first target groove; and a second interconnect layer is formed in the second target groove.

16. The graphical method according to claim 1, characterized in that: The filling layer covers the surface of the first mask layer.

17. A semiconductor device, characterized in that: include: A layer to be etched; A first mask layer, wherein the first mask layer is located on the layer to be etched; A first groove, wherein the first groove is located in the first mask layer, and a plurality of the first grooves are separated from each other and arranged in parallel along a first direction; a filling layer, wherein the filling layer is located in the first groove and completely fills the first groove; a second groove, wherein the second groove is located between adjacent first grooves, a plurality of the second grooves are separated from each other and arranged in parallel along a first direction, and the second grooves expose the side wall of the filling layer; An isolation sidewall is located on the sidewall of the second groove, so that the second groove is formed into a second groove. When removing the filling layer, the selectivity of etching the filling layer is greater than the selectivity of etching the isolation sidewall and the first mask layer. The tops of the isolation sidewall, the filling layer and the first mask layer are flush.

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