This application claims the priority benefit of Taiwan patent application serial no. 112108031, filed on Mar. 6, 2023. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
The disclosure relates to a photomask structure and a patterning method; more particularly, the disclosure relates to a photomask structure and a patterning method which may effectively reduce defects.
At present, in order to reduce a dimension of a semiconductor device, reducing a line width, reducing line spacing, and improving pattern transfer accuracy are issues that should be solved. A self-aligned double patterning (SADP) process is a means to solve the above issues. However, in the SADP process, after patterns of a spacer acting as a mask are transferred to a material layer to form a target structure, there are often spacer residues which may lead to defects.
The disclosure provides a photomask structure and a patterning method capable of effectively reducing defects.
According to an embodiment of the disclosure, a photomask structure that includes a plurality of first layout patterns, a plurality of second layout patterns, and a ring-shaped layout pattern is provided. The first layout patterns and the second layout patterns are alternately arranged. Each of the first layout patterns has a first end and a second end. Each of the second layout patterns has a third end and a fourth end. The first end is adjacent to the third end, and the second end is adjacent to the fourth end. The ring-shaped layout pattern surrounds the first layout patterns and the second layout patterns. The first end is connected to the ring-shaped layout pattern, the second end is not connected to the ring-shaped layout pattern, the third end is not connected to the ring-shaped layout pattern, and the fourth end is connected to the ring-shaped layout pattern.
According to an embodiment of the disclosure, a patterning method includes following steps is provided. A substrate is provided. A material layer is formed on the substrate. A patterned photoresist layer is formed on the material layer by applying the aforesaid photomask structure, and the patterned photoresist layer has an opening. A spacer material layer is conformally formed on the patterned photoresist layer and in the opening. An etch-back process is performed on the spacer material layer, and a spacer is formed on a sidewall of the patterned photoresist layer. The patterned photoresist layer is removed. Patterns of the spacer are transferred to the material layer to form a target structure.
In view of the above, in the photomask structure and the patterning method provided in one or more embodiments of the disclosure, after the patterns of the spacer are transferred to the material layer in the patterning process carried out by applying the photomask structure having said layout design, spacer residues be prevented, and the defects may be effectively reduced. In addition, since the photomask structure and the patterning method provided in one or more embodiments of the disclosure may prevent the spacer residues, it is not necessary to perform any etching process to remove the spacer residues, thereby reducing the manufacturing costs and preventing a height of film layers from being reduced. Besides, the photomask structure and the patterning method provided in one or more embodiments of the disclosure may effectively improve a process window.
To make the above more comprehensible, several embodiments accompanied with drawings are described in detail as follows.
The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.
The embodiments are described in detail below with reference to the accompanying drawings but are not intended to limit the scope provided in the disclosure. For the sake of easy understanding, the same components in the following description will be denoted by the same reference numbers and signs.
With reference to
The layout patterns P1 and the layout patterns P2 are alternately arranged. Each of the layout patterns P1 has an end E1 and an end E2. Each of the layout patterns P2 has an end E3 and an end E4. The end E1 is adjacent to the end E3. The end E2 is adjacent to the end E4. The layout patterns P1 may be separated. The layout patterns P2 may be separated. The layout patterns P1 and the layout patterns P2 may be separated. An extension direction D1 of the layout patterns P1 may be parallel to an extension direction D2 of the layout patterns P2. In some embodiments, a shape of the layout patterns P1 and a shape of the layout patterns P2 may include a bar shape.
The ring-shaped layout pattern P3 surrounds the layout patterns P1 and the layout patterns P2. The end E1 is connected to the ring-shaped layout pattern P3. The end E2 is not connected to the ring-shaped layout pattern P3. The end E3 is not connected to the ring-shaped layout pattern P3. The end E4 is connected to the ring-shaped layout pattern P3.
Hereinafter, a patterning method performed by applying the above-mentioned photomask structure 10 is described with reference to
With reference to
Next, a material layer 102 is formed on the substrate 100. In this embodiment, the material layer 102 may be a film layer to be patterned. In some embodiments, a material of the material layer 102 is, for instance, a dielectric material, a conductive material, or a semiconductor material. In this embodiment, the material of the material layer 10 is, for instance, nitride (e.g., silicon nitride), which should however not be construed as a limitation in the disclosure. In some embodiments, a method of forming the material layer 102 includes, for instance, a chemical vapor deposition (CVD) method or a physical vapor deposition (PVD) method.
A patterned photoresist layer 104 is formed on the material layer 102 by applying the aforesaid photomask structure 10. In some embodiments, the patterned photoresist layer 104 may serve as a core pattern in a SADP process. The patterned photoresist layer 104 has an opening OP1. In some embodiments, the opening OP1 may expose a portion of the material layer 102. The opening OP1 may include a plurality of opening patterns OP11, a plurality of opening patterns OP12, and a ring-shaped opening pattern OP13. The opening patterns OP11 and the opening patterns OP12 may be arranged alternately. Each of the opening patterns OP11 may have an end E5 and an end E6. Each of the opening patterns OP12 may have an end E7 and an end E8. The end E5 is adjacent to the end E7. The end E6 is adjacent to the end E8. The opening patterns OP11 are separated. The opening patterns OP12 are separated. The opening patterns OP11 and the opening patterns OP12 are separated. An extension direction D3 of the opening patterns OP11 may be parallel to an extension direction D4 of the opening patterns OP12. In some embodiments, a shape of the opening patterns OP11 and a shape of the opening patterns OP12 may include a bar shape.
The ring-shaped opening pattern OP13 may surround the opening patterns OP11 and the opening patterns OP12. The end E5 is connected to the ring-shaped opening pattern OP13. The end E6 is not connected to the ring-shaped opening pattern OP13. The end E7 is not connected to the ring-shaped opening pattern OP13. The end E8 is connected to the ring-shaped opening pattern OP13.
The patterned photoresist layer 104 may include a bent portion 104a and a ring-shaped portion 104b. The ring-shaped portion 104b may surround the bent portion 104a. The ring-shaped portion 104b may surround the opening OP1. The ring-shaped opening pattern OP13 may be located between the ring-shaped portion 104b and the bent portion 104a. The ring-shaped opening pattern OP13 may surround the bent portion 104a.
With reference to
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To sum up, in the photomask structure 10 and the patterning method provided in one or more embodiments of the disclosure, after the patterns of the spacer 106a are transferred to the material layer 102 in the patterning process carried out by applying the photomask structure 10 having the above layout design, residues of the spacer 106a may be prevented, thereby effectively reducing defects. In addition, since the above photomask structure 10 and the above patterning method may prevent the residues of the spacer 106a, it is not necessary to perform any etching process to remove the residues of the spacer 106a, thereby reducing the manufacturing costs and preventing the height of the film layers from being reduced. Besides, the above photomask structure 10 and the above patterning method may effectively improve the process window.
It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the disclosure covers modifications and variations provided that they fall within the scope of the following claims and their equivalents.
Number | Date | Country | Kind |
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112108031 | Mar 2023 | TW | national |