TWI893871B - Method of manufacturing mark - Google Patents

Abstract

A method of manufacturing marks including following steps is provided. A substrate is provided. A mark layer is formed on the substrate. A patterned hard mask layer is formed on the mark layer. The patterned hard mask has protrusion portions. The protrusion portions extend in a first direction. A patterned photoresist layer is formed on the patterned hard mask layer. The patterned photoresist layer has first openings exposing a portion of the protrusion portions. The first openings extend in a second direction. The first direction intersects the second direction. The mark layer is patterned to form a mark by using the patterned photoresist layer and the patterned hard mask layer as a mask.

Description

Marking manufacturing method

The present invention relates to a method for manufacturing a semiconductor structure, and in particular to a method for manufacturing a mark.

In semiconductor manufacturing, various marks (such as overlay marks) are used to facilitate smooth process execution. Generally, overlay marks are used to check the alignment between the previous layer and the current layer. However, poor mark structure (e.g., pattern peeling or poor pattern uniformity) can render the mark ineffective. Therefore, creating well-structured marks is an ongoing effort.

The present invention provides a method for manufacturing a mark, which can effectively produce a mark with a good structure to assist the smooth progress of the manufacturing process.

The present invention provides a method for manufacturing a mark, comprising the following steps: providing a substrate; forming a marking layer on the substrate; forming a patterned hard mask layer on the marking layer; the patterned hard mask layer having a plurality of protrusions; the plurality of protrusions extending in a first direction; forming a patterned photoresist layer on the patterned hard mask layer; the patterned photoresist layer having a plurality of first openings exposing a portion of the plurality of protrusions; the plurality of first openings extending in a second direction; the first direction intersecting the second direction; and patterning the marking layer using the patterned photoresist layer and the patterned hard mask layer as masks to form a mark.

According to one embodiment of the present invention, in the aforementioned marking manufacturing method, a method for forming a patterned hard mask layer may include the following steps: forming a hard mask layer on the marking layer; performing a patterning process on the hard mask layer to form a patterned hard mask layer. The patterning process may include a self-aligned multiple patterning (SAMP) process.

According to an embodiment of the present invention, in the method for manufacturing a mark, the plurality of first openings of the patterned photoresist layer can expose a portion of all the protrusions in the second direction.

According to an embodiment of the present invention, in the method for manufacturing the mark, the pattern of the plurality of protrusions may include a plurality of stripe patterns.

According to an embodiment of the present invention, in the method for manufacturing a mark, the number of the first openings may be less than the number of the protrusions.

According to an embodiment of the present invention, in the method for manufacturing the mark, the ends of two adjacent protrusions can be connected to each other to form a ring structure.

According to one embodiment of the present invention, in the above-mentioned method for manufacturing a mark, the patterned photoresist layer can cover the end of the ring-shaped structure.

According to one embodiment of the present invention, in the above-mentioned method for manufacturing a mark, the mark layer may include a multi-layer structure.

According to one embodiment of the present invention, in the above-mentioned method for manufacturing a mark, the mark layer may include a single-layer structure.

According to one embodiment of the present invention, in the marking manufacturing method, the patterned photoresist layer may further include a second opening that exposes another portion of the plurality of protrusions. The second opening may extend in the first direction. The width of the second opening in the second direction may be smaller than the length of the first opening in the second direction.

According to an embodiment of the present invention, in the marking manufacturing method, the second opening can be connected to the first opening.

According to an embodiment of the present invention, the marking manufacturing method may further include the following steps: removing the patterned hard mask layer and the patterned photoresist layer.

According to an embodiment of the present invention, in the method for manufacturing a mark, the plurality of first openings may have the same width.

According to an embodiment of the present invention, in the method for manufacturing a mark, the plurality of first openings may have different widths.

According to an embodiment of the present invention, in the marking manufacturing method, the distances between the plurality of first openings may be the same.

According to an embodiment of the present invention, in the marking manufacturing method, the distances between the plurality of first openings may be different.

According to one embodiment of the present invention, in the above-mentioned method for manufacturing a mark, the patterned photoresist layer can directly contact the patterned hard mask layer.

According to one embodiment of the present invention, the method for manufacturing the mark may further include the following steps: After forming the patterned hard mask layer, forming a hard mask layer on the patterned hard mask layer. The patterned photoresist layer may be formed on the hard mask layer.

According to one embodiment of the present invention, in the method for manufacturing a mark, the substrate may include a scribe line region, and the mark may be located in the scribe line region.

According to one embodiment of the present invention, in the method for manufacturing a mark, the mark may include multiple patterns. Each pattern may include multiple discontinuous strip patterns extending in a first direction. The multiple patterns may be arranged in a second direction.

Based on the above, in the method for manufacturing a mark proposed by the present invention, a patterned hard mask layer is formed on the mark layer. The patterned hard mask layer has a plurality of protrusions. The protrusions extend in a first direction. A patterned photoresist layer is formed on the patterned hard mask layer. The patterned photoresist layer has a plurality of first openings that expose a portion of the protrusions. The plurality of first openings extend in a second direction. The first direction intersects the second direction. The patterned photoresist layer and the patterned hard mask layer serve as masks to pattern the mark layer to form the mark. Thus, a well-structured mark can be effectively produced to facilitate smooth manufacturing processes.

In order to make the above features and advantages of the present invention more clearly understood, embodiments are given below and described in detail with reference to the accompanying drawings.

The following examples are illustrated in detail with accompanying figures. However, these examples are not intended to limit the scope of the present invention. For ease of understanding, identical components will be designated with the same reference numerals throughout the following description. Furthermore, the accompanying figures are for illustrative purposes only and are not drawn to scale. Furthermore, features in the top views are not drawn to the same scale as those in the perspective views. In fact, the dimensions of various features may be arbitrarily increased or decreased for clarity.

Figures 1A to 1D are perspective views of the manufacturing process of a marker according to some embodiments of the present invention. Figure 2A is a top view of Figure 1C. Figures 2B and 2C are top views of Figure 1C according to other embodiments of the present invention. Figure 2D is a top view of still other embodiments of the present invention. Figure 2E is a top view of Figure 1D.

Referring to FIG. 1A , a substrate 100 is provided. In some embodiments, substrate 100 may include a scribe line region SL. Furthermore, substrate 100 may include a device region (not shown) (e.g., a logic device region, a memory device region, or a combination thereof), the description of which is omitted herein. In some embodiments, substrate 100 may be a semiconductor substrate, such as a silicon substrate. Furthermore, substrate 100 may have other desired components (not shown), the description of which is omitted herein.

Next, a marking layer 102 is formed on the substrate 100. The marking layer 102 may be a single-layer structure or a multi-layer structure. The material of the marking layer 102 is, for example, a dielectric material (e.g., oxide or nitride). The marking layer 102 may be formed by, for example, physical vapor deposition (PVD) or chemical vapor deposition (CVD).

Then, a hard mask layer 104 may be formed on the marking layer 102. The material of the hard mask layer 104 may be, for example, a photoresist material, a dielectric material (such as oxide or nitride), or carbon. The hard mask layer 104 may be formed by, for example, physical vapor deposition (PVD) or chemical vapor deposition (CVD).

Referring to FIG. 1B , the hard mask layer 104 may be patterned to form a patterned hard mask layer 106 . This process allows the patterned hard mask layer 106 to be formed on the marking layer 102 . The patterned hard mask layer 106 has a plurality of protrusions P1 . The protrusions P1 extend in a direction D1 . Furthermore, the patterned hard mask layer 106 may have a plurality of openings OP1 . The protrusions P1 may be located between the openings OP1 . In this embodiment, as shown in FIG. 1B , the openings OP1 do not penetrate the patterned hard mask layer 106 , but the present invention is not limited thereto. In other embodiments, although not shown, multiple openings OP1 may penetrate the patterned hard mask layer 106 to expose a portion of the marking layer 102. In some embodiments, the pattern of the multiple protrusions P1 includes multiple stripe patterns LP1. The ends of two adjacent protrusions P1 may be connected to form a ring structure R. In some embodiments, the patterning process may include a self-aligned multiple patterning (SAMP) process, such as a self-aligned double patterning (SADP) process, a self-aligned triple patterning (SATP) process, or a self-aligned quadruple patterning (SAQP) process.

Referring to FIG. 1C and FIG. 2A , a patterned photoresist layer 108 is formed on the patterned hard mask layer 106. The patterned photoresist layer 108 has a plurality of openings OP2 that expose portions of the plurality of protrusions P1. The plurality of openings OP2 extend in a direction D2. Direction D1 intersects direction D2. In this embodiment, the patterned photoresist layer 108 may directly contact the patterned hard mask layer 106. In some embodiments, the plurality of openings OP2 in the patterned photoresist layer 108 expose portions of all of the protrusions P1 in direction D2. In some embodiments, the patterned photoresist layer 108 covers the ends of the ring-shaped structures R. In some embodiments, the patterned photoresist layer 108 may be formed by a lithography process.

In this embodiment, as shown in FIG2A , the plurality of openings OP2 may have the same width W1, but the present invention is not limited thereto. In other embodiments, as shown in FIG2B , the plurality of openings OP2 may have different widths W1 (e.g., width W11 and width W12). Furthermore, openings OP2 having width W11 and openings OP2 having width W12 may be arranged alternately. Because the plurality of openings OP2 may have the same or different widths W1, the pattern of the patterned photoresist layer 108 can be flexibly adjusted.

In this embodiment, as shown in FIG2A , the distance d1 between the plurality of openings OP2 may be the same, but the present invention is not limited thereto. In other embodiments, as shown in FIG2C , the distance d1 between the plurality of openings OP2 (e.g., distance d11 and distance d12) may be different. For example, the distance d11 between the plurality of openings OP2 and the distance d12 between the plurality of openings OP2 may be arranged alternately. Because the distance d1 between the plurality of openings OP2 can be the same or different, the pattern of the patterned photoresist layer 108 can be flexibly adjusted.

In some embodiments, the number of openings OP2 may be less than the number of protrusions P1, but the present invention is not limited thereto. In other embodiments, the number of openings OP2 may be greater than or equal to the number of protrusions P1. Furthermore, the number of openings OP2 is not limited to the number shown in the figure. Any configuration comprising a plurality of openings OP2 falls within the scope of the present invention.

In some embodiments, the scribe line region SL includes a first region R1 in FIG. 2A and a second region R2 in FIG. 2D . In some embodiments, the first region R1 in FIG. 2A and the second region R2 in FIG. 2D may be separate regions. Furthermore, a patterned hard mask layer 106 and a patterned photoresist layer 108 may be formed in the second region R2. The patterned photoresist layer 108 may include the photoresist pattern of FIG. 2A and the photoresist pattern of FIG. 2D . That is, the patterned photoresist layer 108 may include an opening OP2 that exposes a portion of the plurality of protrusions P1, and the patterned photoresist layer 108 may further include an opening OP3 that exposes another portion of the plurality of protrusions P1. The opening OP3 extends in a direction D1. The width W2 of the opening OP3 in the direction D2 is less than the length L1 of the opening OP2 in the direction D2. In some embodiments, since the opening OP3 exposes a portion of the protrusion P1, the relative position of the edge of the opening OP3 and the protrusion P1 can be used to determine whether the photoresist pattern of the patterned photoresist layer 108 has shifted. This can thereby monitor whether the photoresist pattern of the patterned photoresist layer 108 in the device region (e.g., the memory array region) (not shown) has shifted.

In some embodiments, opening OP3 may be connected to opening OP2, and at least one corner C1 is formed at the connection between opening OP3 and opening OP2. In some embodiments, the relative position of corner C1 and protrusion P1 can be used to determine whether the photoresist pattern of patterned photoresist layer 108 has shifted, thereby monitoring whether the photoresist pattern of patterned photoresist layer 108 in a device region (e.g., a memory array region) (not shown) has shifted.

In FIG. 2A to FIG. 2D , the same or similar components are denoted by the same symbols, and their descriptions are omitted.

Referring to FIG. 1D and FIG. 2E , the mark layer 102 is patterned using the patterned photoresist layer 108 and the patterned hard mask layer 106 as masks to form a mark 110. In this embodiment, the mark 110 may be located within the scribe line region SL. Furthermore, the mark 110 may be used as an overlay mark or an alignment mark, but the present invention is not limited thereto.

Furthermore, the patterned hard mask layer 106 and the patterned photoresist layer 108 can be removed. In some embodiments, the patterned photoresist layer 108 and the patterned hard mask layer 106 can be consumed and removed during the patterning of the marking layer 102. In other embodiments, after the marking layer 102 is patterned, if the patterned photoresist layer 108 and/or the patterned hard mask layer 106 are not removed, the patterned photoresist layer 108 and/or the patterned hard mask layer 106 can be removed through an additional process (e.g., an etching process).

In some embodiments, the marking 110 may include multiple patterns P2. Each pattern P2 may include multiple discontinuous stripe patterns LP2 extending in direction D1. The multiple discontinuous stripe patterns LP2 may be aligned with one another in direction D1. The multiple patterns P2 may be arranged in direction D2. Multiple stripe patterns LP2 within the multiple patterns P2 may be aligned with one another in direction D2. In some embodiments, the pattern P2 may be an opening in the marking 110.

In some embodiments, the mark 110 may include multiple patterns P3. The multiple patterns P3 may be located on both sides of the multiple patterns P2. Each pattern P2 may include multiple discontinuous strip patterns LP3 extending in direction D1. The multiple discontinuous strip patterns LP3 may be aligned with each other in direction D1. The multiple patterns P3 and the multiple patterns P2 may be arranged in direction D2. The multiple strip patterns LP3 in the multiple patterns P3 and the multiple strip patterns LP2 in the multiple patterns P2 may be aligned with each other in direction D2. In some embodiments, the width W3 of the strip pattern LP2 in direction D1 may be equal to the width W4 of the strip pattern LP3 in direction D1. In some embodiments, the length L2 of the strip pattern LP2 in direction D2 may be less than the length L3 of the strip pattern LP3 in direction D2. In some embodiments, pattern P3 may be an opening in mark 110 .

As can be seen from the above-described embodiment, in the method for manufacturing the mark 100, a patterned hard mask layer 106 is formed on the mark layer 102. The patterned hard mask layer 106 has a plurality of protrusions P1. The plurality of protrusions P1 extend in a direction D1. A patterned photoresist layer 108 is formed on the patterned hard mask layer 106. The patterned photoresist layer 108 has a plurality of openings OP2 that expose a portion of the plurality of protrusions P1. The plurality of openings OP2 extend in a direction D2. Direction D1 intersects with direction D2. Using the patterned photoresist layer 108 and the patterned hard mask layer 106 as masks, the mark layer 102 is patterned to form the mark 110. As a result, a well-structured mark 110 can be effectively manufactured to facilitate smooth manufacturing processes.

3A to 3B are three-dimensional views of the manufacturing process according to some other embodiments of the present invention. In some embodiments, FIG3A is a three-dimensional view of the manufacturing process following FIG1B.

Referring to Figures 3A and 3B , the manufacturing process of Figures 1C to 1D differs from the manufacturing process of Figures 3A and 3B as follows. The patterned photoresist layer 108 of Figure 1C may directly contact the patterned hard mask layer 106, while the patterned photoresist layer 108 of Figure 3A does not directly contact the patterned hard mask layer 106. For example, in Figure 3A , after forming the patterned hard mask layer 106, a hard mask layer 112 may be formed on the patterned hard mask layer 106. The patterned photoresist layer 108 may be formed on the hard mask layer 112. The hard mask layer 112 may be a single-layer structure or a multi-layer structure. The material of the hard mask layer 112 may be, for example, a dielectric material (e.g., an oxide or a nitride). The hard mask layer 112 is formed by, for example, physical vapor deposition (PVD) or chemical vapor deposition (CVD).

3B, the marking layer 102 is patterned using the patterned photoresist layer 108 and the patterned hard mask layer 106 as masks to form a mark 110. In FIG1C to FIG1D and FIG3A to FIG3B, the same or similar components are represented by the same symbols and their descriptions are omitted.

In summary, in the marking manufacturing method of the above-described embodiment, a patterned hard mask layer is formed on the marking layer. The patterned hard mask layer has a plurality of protrusions. The protrusions extend in a first direction. A patterned photoresist layer is formed on the patterned hard mask layer. The patterned photoresist layer has a plurality of first openings that expose a portion of the protrusions. The plurality of first openings extend in a second direction. The first direction intersects the second direction. The patterned photoresist layer and the patterned hard mask layer serve as masks to pattern the marking layer to form the marking. Thus, a well-structured mark can be effectively manufactured to facilitate smooth manufacturing processes.

Although the present invention has been disclosed above by way of embodiments, they are not intended to limit the present invention. Any person having ordinary skill in the art may make slight modifications and improvements 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 scope of the attached patent application.

100: Substrate 102: Marking layer 104, 112: Hard mask layer 106: Patterned hard mask layer 108: Patterned photoresist layer 110: Mark C1: Corner d1, d11, d12: Distance D1, D2: Direction L1, L2, L3: Length LP1, LP2, LP3: Stripe pattern OP1, OP2, OP3: Opening P1: Protrusion P2, P3: Pattern R: Ring structure R1: First region R2: Second region SL: Slice street area W1, W2, W3, W4, W11, W12: Width

Figures 1A to 1D are perspective views of the manufacturing process for markings according to some embodiments of the present invention. Figure 2A is a top view of Figure 1C. Figures 2B and 2C are top views of Figure 1C according to other embodiments of the present invention. Figure 2D is a top view of other embodiments of the present invention. Figure 2E is a top view of Figure 1D. Figures 3A and 3B are perspective views of the manufacturing process for markings according to other embodiments of the present invention.

100: Base

102: Marker layer

106: Patterned hard mask layer

108: Patterned photoresist layer

D1, D2: Direction

LP1: Stripe pattern

OP1, OP2: Opening

P1: Protrusion

R: Ring structure

R1: Zone 1

SL: Cutting area

Claims (20)

A method for manufacturing a mark includes: providing a substrate; forming a mark layer on the substrate; forming a patterned hard mask layer on the mark layer, wherein the patterned hard mask layer has a plurality of protrusions extending in a first direction; forming a patterned photoresist layer on the patterned hard mask layer, wherein the patterned photoresist layer has a plurality of first openings exposing a portion of the plurality of protrusions, the plurality of first openings extending in a second direction, and the first direction intersecting the second direction; and patterning the mark layer using the patterned photoresist layer and the patterned hard mask layer as masks to form a mark. The method for manufacturing a mark as described in claim 1, wherein the method for forming the patterned hard mask layer includes: forming a hard mask layer on the mark layer; and performing a patterning process on the hard mask layer to form the patterned hard mask layer, wherein the patterning process includes a self-aligned multi-patterning process. The method for manufacturing a mark as described in claim 1, wherein the plurality of first openings of the patterned photoresist layer expose a portion of all the protrusions in the second direction. A method for manufacturing a mark as described in claim 1, wherein the patterns of the plurality of protrusions include a plurality of stripe patterns. A method for manufacturing a mark as described in claim 1, wherein the number of the first openings is less than the number of the protrusions. A method for manufacturing a mark as described in claim 1, wherein the ends of two adjacent protrusions are connected to each other to form a ring structure. The method for manufacturing a mark as described in claim 6, wherein the patterned photoresist layer covers the end of the ring structure. A method for manufacturing a mark as described in claim 1, wherein the mark layer includes a multi-layer structure. A method for manufacturing a mark as described in claim 1, wherein the mark layer includes a single-layer structure. A method for manufacturing a mark as described in claim 1, wherein the patterned photoresist layer further includes a second opening exposing another portion of the plurality of protrusions, the second opening extends in the first direction, and the width of the second opening in the second direction is less than the length of the first opening in the second direction. A method for manufacturing a mark as described in claim 10, wherein the second opening is connected to the first opening. The method for manufacturing a mark as claimed in claim 1 further comprises: removing the patterned hard mask layer and the patterned photoresist layer. A method for manufacturing a mark as described in claim 1, wherein multiple first openings have the same width. A method for manufacturing a mark as described in claim 1, wherein multiple first openings have different widths. A method for manufacturing a mark as described in claim 1, wherein the distances between multiple first openings are the same. A method for manufacturing a mark as described in claim 1, wherein the distances between multiple first openings are different. The method for manufacturing a mark as claimed in claim 1, wherein the patterned photoresist layer directly contacts the patterned hard mask layer. The method for manufacturing a mark according to claim 1 further comprises: after forming the patterned hard mask layer, forming a hard mask layer on the patterned hard mask layer, wherein the patterned photoresist layer is formed on the hard mask layer. A method for manufacturing a mark as described in claim 1, wherein the substrate includes a cutting street area, and the mark is located in the cutting street area. A method for manufacturing a mark as described in claim 1, wherein the mark includes a plurality of patterns, each of the patterns includes a plurality of discontinuous strip patterns extending in the first direction, and a plurality of the patterns are arranged in the second direction.