Patterning method

Abstract

A method of patterning includes the following steps. A material layer is provided. A first patterned mask layer is formed on the material layer. The first patterned mask layer includes openings. A second patterned mask layer is formed in the openings. The material of the second patterned mask layer includes a negative thermal expansion material. The second patterned mask layer is subjected to a heating process that shrinks the second patterned mask layer and forms a gap between the first patterned mask layer and the second patterned mask layer. Portions of the material layer are removed using the first patterned mask layer and the second patterned mask layer as masks to pattern the material layer.

Description

Technical Field

[0001] This invention relates to a semiconductor manufacturing process, and more particularly to a patterning method. Background Technology

[0002] Currently, reducing the size of semiconductor devices, decreasing linewidth, reducing line spacing, and improving pattern transfer accuracy are essential challenges. Self-aligned double patterning (SADP) is one approach to addressing these challenges. However, due to the high process complexity of current SADP processes, developing a patterning method with lower process complexity remains a continuous goal. Summary of the Invention

[0003] This invention provides a patterning method that can effectively reduce process complexity.

[0004] This invention proposes a patterning method comprising the following steps: A material layer is provided. A first patterned mask layer is formed on the material layer. The first patterned mask layer includes an opening. A second patterned mask layer is formed in the opening. The material of the second patterned mask layer includes a negative thermal expansion material. The second patterned mask layer is subjected to a heating process to shrink the second patterned mask layer and form a gap between the first and second patterned mask layers. Using the first and second patterned mask layers as a mask, a portion of the material layer is removed to pattern the material layer.

[0005] According to an embodiment of the present invention, in the above-described patterning method, the method for forming a first patterned mask layer may include the following steps: forming a mask layer on a material layer; and patterning the mask layer to form a first patterned mask layer.

[0006] According to an embodiment of the present invention, in the above-described patterning method, the negative thermal expansion material may include ZrV. 1.6 W 0.4 O 7.2 Zr(WO4)2, ZrV2O, ZrMo2O8, ZrW2O8, HfMo2O8, HfW2O8, Zr2(MoO4)3, Zr2(WO4)3, Hf2(MoO4)3, Hf2(WO4)3 or combinations thereof.

[0007] According to an embodiment of the present invention, in the above-described patterning method, the method for forming a second patterned mask layer may include the following steps: forming a mask layer on a first patterned mask layer and within an opening; removing the mask layer located outside the opening to form a second patterned mask layer.

[0008] According to an embodiment of the present invention, in the above patterning method, the method for forming the mask layer is, for example, a spin coating method.

[0009] According to an embodiment of the present invention, in the above-described patterning method, the method for removing the cover layer located outside the opening is, for example, dry etching or chemical mechanical polishing.

[0010] According to one embodiment of the present invention, in the above patterning method, the temperature of the heating process is, for example, 100°C to 500°C.

[0011] According to an embodiment of the present invention, in the above-described patterning method, the top view pattern of the opening is, for example, a rectangle or a circle.

[0012] According to an embodiment of the present invention, in the above patterning method, the top view pattern of the second patterned mask layer is, for example, rectangular or circular.

[0013] According to an embodiment of the present invention, in the above-described patterning method, the upper view pattern of the gap is, for example, annular.

[0014] Based on the above, in the patterning method proposed in this invention, since the material of the second patterned mask layer includes a material with negative thermal expansion, the second patterned mask layer can have a negative coefficient of thermal expansion. In this way, the second patterned mask layer can be reduced in size by a heating process, forming a gap between the first and second patterned mask layers, thereby effectively reducing process complexity. Furthermore, the size of the second patterned mask layer and the size of the gap can be flexibly adjusted by adjusting the temperature of the heating process.

[0015] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings. Attached Figure Description

[0016] Figures 1A to 1F This is a cross-sectional view of a patterning process according to some embodiments of the present invention.

[0017] Figures 2A to 2C According to some embodiments of the present invention Figure 1B , Figure 1D and Figure 1E The top view.

[0018] Figures 3A to 3C According to other embodiments of the present invention Figure 1B , Figure 1D and Figure 1E The top view.

[0019] Symbol Explanation

[0020] 100: Base

[0021] 102: Material layer

[0022] 102a: Patterned material layer

[0023] 104, 106: Covering layer

[0024] 104a, 106a: Patterned masking layers

[0025] G1: Gap

[0026] OP1: Opening Detailed Implementation

[0027] The following description provides detailed examples and accompanying drawings, but these examples are not intended to limit the scope of the invention. For ease of understanding, the same components will be designated with the same symbols in the following description. Furthermore, the drawings are for illustrative purposes only and are not drawn to their original dimensions. In fact, the dimensions of various features may be increased or decreased arbitrarily for clarity of explanation.

[0028] Figures 1A to 1F This is a cross-sectional view of a patterning process according to some embodiments of the present invention. Figures 2A to 2C According to some embodiments of the present invention Figure 1B , Figure 1D and Figure 1E The top view. Figures 1A to 1F For along Figures 2A to 2C A cross-sectional view of the I-I' section line in the diagram. Figures 3A to 3C According to other embodiments of the present invention Figure 1B , Figure 1D and Figure 1E The top view. Furthermore, the patterning process in some embodiments of the present invention may be a self-aligned dual patterning process.

[0029] Please refer to Figure 1AA material layer 102 is provided. For example, the material layer 102 may be provided on a substrate 100. The substrate 100 may be a semiconductor substrate, such as a silicon substrate. The material layer 102 may be a pre-patterned film layer. In some embodiments, the material of the material layer 102 may be a dielectric material, a conductive material, or a semiconductor material. In some embodiments, the dielectric material is, for example, silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon carbonitride, or a combination thereof. In some embodiments, the conductive material is, for example, a metal. In some embodiments, the semiconductor material is, for example, silicon. In this embodiment, the material of the material layer 102 is silicon oxide, but the invention is not limited thereto. In some embodiments, the method of forming the material layer 102 is, for example, chemical vapor deposition or physical vapor deposition. In other embodiments, the substrate 100 may be a pre-patterned material layer, and the material layer 102 may be omitted as needed.

[0030] Next, a mask layer 104 may be formed on the material layer 102. In some embodiments, the material of the mask layer 104 may be a dielectric material, a semiconductor material, or a conductive material. In some embodiments, the dielectric material is, for example, silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon carbonitride, or a combination thereof. In some embodiments, the semiconductor material is, for example, polycrystalline silicon. In some embodiments, the conductive material is, for example, a metal. In this embodiment, polycrystalline silicon is used as an example of the material of the mask layer 104, but the present invention is not limited thereto. In some embodiments, the method for forming the mask layer 104 is, for example, chemical vapor deposition or physical vapor deposition.

[0031] Please refer to Figure 1B and Figure 2A The mask layer 104 can be patterned to form a patterned mask layer 104a. This allows the patterned mask layer 104a to be formed on the material layer 102. The patterned mask layer 104a includes an opening OP1. In some embodiments, the opening OP1 may expose the material layer 102. In this embodiment, as... Figure 2A As shown, the top view pattern of opening OP1 is, for example, rectangular, but the invention is not limited thereto. In other embodiments, such as... Figure 3A As shown, the top view pattern of the opening OP1 is, for example, circular. In some embodiments, the mask layer 104 may be patterned by lithography and etching processes.

[0032] Please refer to Figure 1C A mask layer 106 can be formed on the patterned mask layer 104a and in the opening OP1. In some embodiments, the material of the mask layer 106 may include a negative thermal expansion material. In some embodiments, the negative thermal expansion material may include ZrV. 1.6 W 0.4 O 7.2Zr(WO4)2, ZrV2O, ZrMo2O8, ZrW2O8, HfMo2O8, HfW2O8, Zr2(MoO4)3, Zr2(WO4)3, Hf2(MoO4)3, Hf2(WO4)3, or combinations thereof. In some embodiments, the method for forming the mask layer 106 is, for example, spin coating.

[0033] Please refer to Figure 1D and Figure 2B The masking layer 106 located outside the opening OP1 can be removed to form a patterned masking layer 106a. This allows the patterned masking layer 106a to be formed within the opening OP1. In some embodiments, the patterned masking layer 106a may directly contact the material layer 102 and the patterned masking layer 104a. The material of the patterned masking layer 106a includes a negative thermal expansion material. In some embodiments, the negative thermal expansion material may include ZrV. 1.6 W 0.4 O 7.2 Zr(WO4)2, ZrV2O, ZrMo2O8, ZrW2O8, HfMo2O8, HfW2O8, Zr2(MoO4)3, Zr2(WO4)3, Hf2(MoO4)3, Hf2(WO4)3, or combinations thereof. In this embodiment, as... Figure 2B As shown, the top view pattern of the patterned mask layer 106a is, for example, rectangular, but the invention is not limited thereto. In other embodiments, such as Figure 3B As shown, the top view pattern of the patterned mask layer 106a is, for example, circular. In some embodiments, the mask layer 106 located outside the opening OP1 is removed by, for example, dry etching or chemical mechanical polishing.

[0034] Please refer to Figure 1E and Figure 2C A heating process is performed on the patterned mask layer 106a to shrink it, and a gap G1 is formed between the patterned mask layer 104a and the patterned mask layer 106a. In some embodiments, the top view pattern of the gap G1 is, for example, annular. In this embodiment, as... Figure 2C As shown, the top view pattern of gap G1 is, for example, a square ring, but the invention is not limited thereto. In other embodiments, such as Figure 3C As shown, the top view pattern of gap G1 is, for example, an annular shape. In some embodiments, the temperature of the heating process is, for example, 100°C to 500°C.

[0035] Please refer to Figure 1FUsing patterned mask layers 104a and 106a as masks, a portion of the material layer 102 is removed, thereby patterning the material layer 102. This allows the patterns of the patterned mask layers 104a and 106a to be transferred to the material layer 102, forming a patterned material layer 102a. In some embodiments, the method for removing a portion of the material layer 102 is, for example, dry etching. Furthermore, the patterned mask layers 104a and 106a can be consumed during the above process or removed subsequently.

[0036] As can be seen from the above embodiments, in the patterning method described above, since the material of the patterned mask layer 106a includes a material with negative thermal expansion, the patterned mask layer 106a can have a negative coefficient of thermal expansion. In this way, the patterned mask layer 106a can be reduced in size by the heating process, forming a gap G1 between the patterned mask layer 104a and the patterned mask layer 106a, thereby effectively reducing process complexity. Furthermore, the size of the patterned mask layer 106a and the size of the gap G1 can be flexibly adjusted by adjusting the temperature of the heating process.

[0037] In summary, the patterning method of the above embodiments includes the following steps: A material layer is provided. A first patterned mask layer is formed on the material layer. The first patterned mask layer includes an opening. A second patterned mask layer is formed in the opening. The material of the second patterned mask layer includes a material with negative thermal expansion. A heating process is performed on the second patterned mask layer to shrink the second patterned mask layer and form a gap between the first patterned mask layer and the second patterned mask layer. Using the first and second patterned mask layers as a mask, a portion of the material layer is removed to pattern the material layer. Since the material of the second patterned mask layer includes a material with negative thermal expansion, the second patterned mask layer can have a negative coefficient of thermal expansion. In this way, the second patterned mask layer can be shrunk by the heating process, and a gap can be formed between the first and second patterned mask layers, thereby effectively reducing process complexity. Furthermore, the size of the second patterned mask layer and the size of the gap can be flexibly adjusted by adjusting the temperature of the heating process.

[0038] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A patterning method, comprising: Provide material layers; A first patterned mask layer is formed on the material layer, wherein the first patterned mask layer includes an opening; A second patterned dome layer is formed in the opening, wherein the material of the second patterned dome layer includes a material with negative thermal expansion; A heating process is performed on the second patterned mask layer to shrink the second patterned mask layer and to form a gap between the first patterned mask layer and the second patterned mask layer. as well as Using the first patterned mask layer and the second patterned mask layer as a mask, a portion of the material layer is removed, and the material layer is patterned.

2. The patterning method of claim 1, wherein the method for forming the first patterned mask layer comprises: A cover layer is formed on the material layer; as well as The mask layer is patterned to form the first patterned mask layer.

3. The patterning method of claim 1, wherein the negative thermal expansion material comprises ZrV. 1.6 W 0.4 O 7.2 Zr(WO4)2, ZrV2O, ZrMo2O8, ZrW2O8, HfMo2O8, HfW2O8, Zr2(MoO4)3, Zr2(WO4)3, Hf2(MoO4)3, Hf2(WO4)3 or combinations thereof.

4. The patterning method of claim 1, wherein the method for forming the second patterned mask layer comprises: A mask layer is formed on the first patterned mask layer and in the opening; as well as The cover layer located outside the opening is removed to form the second patterned cover layer.

5. The patterning method of claim 4, wherein the method for forming the mask layer includes a spin coating method.

6. The patterning method of claim 4, wherein the method for removing the cover layer located outside the opening comprises dry etching or chemical mechanical polishing.

7. The patterning method of claim 1, wherein the temperature of the heating process is from 100°C to 500°C.

8. The patterning method of claim 1, wherein the top view pattern of the opening comprises a rectangle or a circle.

9. The patterning method of claim 1, wherein the top view pattern of the second patterned mask layer includes a rectangle or a circle.

10. The patterning method of claim 1, wherein the upper view pattern of the gap comprises an annular shape.

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