CN115548042A - Method for manufacturing semiconductor element - Google Patents

Abstract

The invention discloses a semiconductor element, which comprises a substrate, a first dielectric layer structure, a second dielectric layer structure, a first light blocking structure, a second light blocking structure, a dielectric layer and a bonding pad layer. The substrate is provided with a first surface, a second surface opposite to the first surface and a first opening. The first dielectric layer structure is arranged on the first surface and is provided with a conductor layer and a second opening. The second opening exposes the conductor layer and is connected with the first opening. The second dielectric layer structure is arranged on the second surface and is provided with a third opening. The third opening exposes a portion of the substrate and connects to the first opening. The first light blocking structure is arranged on the second dielectric layer structure. The second light blocking structure is arranged on the side wall of the third opening. The dielectric layer is arranged on the light blocking structure and in the third opening, and is provided with a fourth opening connected with the first opening. The pad layer is disposed on the dielectric layer and in the fourth opening, and is electrically connected to the conductive layer. The semiconductor element can prevent the damage of the cushion layer caused by the manufacturing process for forming the light blocking structure.

Description

Manufacturing method of semiconductor element

This application is a divisional application of the invention patent application with the application number 201810449833.4 and the invention name "Method for Manufacturing Semiconductor Element" filed on May 11, 2018.

technical field

The present invention relates to a semiconductor, and in particular to a semiconductor element.

Background technique

At present, in the fabrication process of light-related semiconductor elements, light-shielding structures are fabricated. For example, in the manufacturing process of the image sensor, the pads are fabricated first, and then the light-shielding structure (eg, metal grid) is fabricated. As a result, the manufacturing process (eg, etching process) used to form the light-shielding structure is likely to cause damage to the pads.

Contents of the invention

The invention provides a semiconductor element, which can prevent the damage to the pad layer caused by the manufacturing process used to form the light-shielding structure.

The invention provides a semiconductor element, which includes a substrate, a first dielectric layer structure, a second dielectric layer structure, a first light-shielding structure, a second light-shielding structure, a dielectric layer and a pad layer. The base has a first surface, a second surface opposite to the first surface, and a first opening. The first dielectric layer structure is disposed on the first surface and has a conductive layer and a second opening. The second opening exposes the conductor layer and is connected to the first opening. The second dielectric layer structure is disposed on the second surface and has a third opening. The third opening exposes a portion of the base and is connected to the first opening. The first light blocking structure is disposed on the second dielectric layer structure. The second light blocking structure is disposed on the sidewall of the third opening. The dielectric layer is disposed on the light-shielding structure and in the third opening, and has a fourth opening connected to the first opening. The pad layer is disposed on the dielectric layer and in the fourth opening, and is electrically connected to the conductor layer.

According to an embodiment of the present invention, in the above semiconductor device, the first light blocking structure is not connected to the second light blocking structure.

According to an embodiment of the present invention, in the above semiconductor device, the first light blocking structure and the second light blocking structure are metal grids.

According to an embodiment of the present invention, in the above semiconductor device, the second light blocking structure and the pad layer are separated from each other.

According to an embodiment of the present invention, in the above semiconductor device, the second light-shielding structure and the dielectric layer are disposed on a part of the substrate.

According to an embodiment of the present invention, in the above semiconductor device, the dielectric layer in the third opening covers the second light blocking structure.

According to an embodiment of the present invention, in the above semiconductor device, the pad layer is further disposed in the first opening and the second opening.

According to an embodiment of the present invention, in the above semiconductor device, the second dielectric layer structure further has a fifth opening. The fifth opening exposes a portion of the base. The semiconductor component also includes a third light blocking structure. The third light blocking structure is disposed in the fifth opening.

According to an embodiment of the present invention, in the above semiconductor element, the first light blocking structure is connected to the third light blocking structure.

Based on the above, in the semiconductor device of the present invention, since the pad layer is formed after the light-shielding structure is formed, damage to the pad layer due to the fabrication process for forming the light-shielding structure can be prevented. In addition, the photomask can reduce the number of photomasks used in the manufacturing process of the semiconductor element by the method for manufacturing the semiconductor element of the present invention, thereby reducing the production cost.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

Description of drawings

1A to 1E are cross-sectional views of the manufacturing process of a semiconductor device according to an embodiment of the present invention;

2A to 2G are cross-sectional views of a manufacturing process of a semiconductor device according to another embodiment of the present invention.

Symbol Description

100, 200: base

102, 104, 202, 204: dielectric layer structure

106, 206: conductor layer

108, 110, 116, 208, 212, 218: opening

112, 214: light blocking structure

114, 216: dielectric layer

118, 220: pad layer

210: Patterned photoresist layer

S1, S3: the first side

S2, S4: the first side

W1, W2: Width

detailed description

1A to 1E are cross-sectional views of a manufacturing process of a semiconductor device according to an embodiment of the present invention.

Referring to FIG. 1A , a substrate 100 is provided. The substrate 100 is, for example, a semiconductor substrate, such as a silicon substrate. The substrate 100 may have a photosensitive element (not shown), such as a photodiode. A dielectric layer structure 102 is provided on the first side S1 of the substrate 100, a dielectric layer structure 104 is provided on the second side S2 of the substrate 100 opposite to the first side S1, and a conductor layer is provided in the dielectric layer structure 102 106. In this embodiment, the first surface S1 is an example of the front of the substrate 100 , and the second surface S2 is an example of the back of the substrate 100 , but the invention is not limited thereto.

The dielectric layer structure 102, 104 can be a multi-layer structure or a single-layer structure. The material of the dielectric layer structures 102 , 104 is, for example, silicon oxide, silicon nitride, high dielectric constant material (eg, hafnium oxide (HfO) or tantalum oxide (TaO)) or a combination thereof. Those skilled in the art can select the number of layers and materials of the dielectric layer structure according to product requirements.

In addition, although only the conductor layer 106 in the dielectric layer structure 102 is shown, the dielectric layer structure 102 may still include other interconnect structures. The conductive layer 106 may be the interconnection structure closest to the substrate 100 among the interconnection structures. The material of the conductor layer 106 is, for example, metal, such as aluminum, tungsten or copper.

An opening 108 exposing the substrate 100 and above the conductive layer 106 is formed in the dielectric layer structure 104 . The opening 108 is, for example, a photomask formed by using a photolithographic etching process. In addition, an opening 110 exposing the substrate 100 may be formed in the dielectric layer structure 104 . The opening 110 and the opening 108 can be formed by the same photolithography process.

Referring to FIG. 1B , a light blocking structure 112 is formed on the dielectric layer structure 104 . The light blocking structure 112 is, for example, a metal grid. In addition, the light blocking structure 112 can also be formed on the sidewall of the opening 108 and in the opening 110 . The material of the light blocking structure 112 is, for example, metal, such as tungsten or aluminum. The method for forming the light-shielding structure 112 is, for example, first to form a light-shielding material layer (not shown) on the dielectric layer structure 104 through a deposition process with a photomask, and then to form a light-shielding material layer (not shown) on the light-shielding material layer through a photolithographic etching process. for patterning.

Referring to FIG. 1C , a dielectric layer 114 covering the light blocking structure 112 and filling the opening 108 is formed. The material of the dielectric layer 114 is, for example, silicon oxide. The dielectric layer 114 is formed by, for example, chemical vapor deposition. In addition, a planarization process, such as a chemical mechanical polishing process, may be performed on the dielectric layer 114 .

Referring to FIG. 1D , an opening 116 exposing the conductor layer 106 is formed in the dielectric layer 114 and the substrate 100 . In addition, the opening 116 can also extend into the dielectric layer structure 102 . The opening 108 is formed by, for example, a photomask through a photolithography process. Opening 116 and opening 108 (FIG. 1A) may be formed by the same or different photomasks. In this embodiment, the opening 116 and the opening 108 are formed by different photomasks as an example, but the invention is not limited thereto.

In another embodiment, in the case that the opening 116 and the opening 108 are formed by the same photomask, during the etching process for forming the opening 116 , etching is performed at the position of the opening 110 at the same time. At this time, the material of the light-shielding structure 112 is preferably selected from a material (eg, aluminum) with high etching resistance in this etching process, so as to prevent the light-shielding structure 112 from being damaged during the etching process.

Referring to FIG. 1E , a pad layer 118 electrically connected to the conductor layer 106 is formed in the opening 116 . The material of the pad layer 118 is, for example, metal, such as aluminum, tungsten or copper. The formation method of the pad layer 118 is, for example, first to form a pad material layer (not shown) filling the opening 116 on the dielectric layer 114 through a deposition process through a photomask, and then to butt the photomask through a photolithography etching process. The pad material layer is patterned.

Based on the foregoing embodiments, it can be known that, in the above-mentioned manufacturing method of the semiconductor element, since the pad layer 118 is formed after the light-shielding structure 112 is formed, it is possible to prevent the manufacturing process (such as etching process) for forming the light-shielding structure 112 from being formed. process) damages the pad layer 118 . In addition, the photomask can reduce the number of photomasks required for the manufacturing process of the semiconductor element by using the method for manufacturing the semiconductor element in the above embodiment, thereby reducing the production cost.

2A to 2G are cross-sectional views of a manufacturing process of a semiconductor device according to another embodiment of the present invention.

Referring to FIG. 2A , a substrate 200 is provided. On the first surface S3 of the substrate 200, there is a dielectric layer structure 202, on the second surface S4 of the substrate 200 opposite to the first surface S3, there is a dielectric layer structure 204, and in the dielectric layer structure 202 there is a conductor layer 206. Regarding the relevant content of the substrate 200, the dielectric layer structure 202, the dielectric layer structure 204, and the conductive layer 206, please refer to the description of the substrate 100, the dielectric layer structure 102, the dielectric layer structure 104, and the conductive layer 106 in FIG. 1A. This will not be repeated.

A patterned photoresist layer 210 having openings 208 is formed on the dielectric layer structure 204 . Opening 208 may have a width W1. The patterned photoresist layer 210 is, for example, a photomask formed by a photolithography process.

Referring to FIG. 2B , the patterned photoresist layer 210 can be trimmed to expand the width W1 of the opening 208 to a width W2, which helps to expand the critical dimension of the subsequently formed pad layer. dimension, CD). The trimming process is, for example, a chemical trim process and a plasma trim process.

2C, using the patterned photoresist layer 210 as a mask, part of the dielectric layer structure 204 is removed, and an opening 212 that exposes the substrate 200 and is located above the conductor layer 206 is formed in the dielectric layer structure 204. . In this embodiment, in the forming method of the opening 212, the opening 110 as in FIG. 1A is not formed at the same time.

Next, the patterned photoresist layer 210 is removed. The removal method of the patterned photoresist layer 210 is, for example, a dry photoresist stripping method or a wet photoresist stripping method.

Referring to FIG. 2D , a light blocking structure 214 is formed on the dielectric layer structure 204 . The light blocking structure 214 is, for example, a metal grid. In addition, the light blocking structure 214 can also be formed on the sidewall of the opening 212 . The material of the light blocking structure 214 is, for example, metal, such as tungsten or aluminum. The method for forming the light-shielding structure 214 is, for example, first to form a light-shielding material layer (not shown) on the dielectric layer structure 204 through a deposition process with a photomask, and then to form a light-shielding material layer (not shown) on the light-shielding material layer through a photolithographic etching process. for patterning.

Referring to FIG. 2E , a dielectric layer 216 covering the light blocking structure 214 and filling the opening 212 is formed. The material of the dielectric layer 216 is, for example, silicon oxide. The dielectric layer 216 is formed by, for example, chemical vapor deposition. In addition, a planarization process, such as a chemical mechanical polishing process, may be performed on the dielectric layer 216 .

Referring to FIG. 2F , an opening 218 exposing the conductor layer 206 is formed in the dielectric layer 216 and the substrate 200 . In addition, the opening 218 can also extend into the dielectric layer structure 202 . The opening 212 is formed by, for example, a photomask through a photolithography process. Opening 218 and opening 212 (FIG. 2C) may be formed by the same or different photomasks. In this embodiment, the opening 218 and the opening 212 are formed by the same photomask as an example, but the invention is not limited thereto.

Referring to FIG. 2G , a pad layer 220 electrically connected to the conductor layer 206 is formed in the opening 218 . The material of the pad layer 220 is, for example, metal, such as aluminum, tungsten or copper. The formation method of the pad layer 220 is, for example, first to form a pad material layer (not shown) filling the opening 218 on the dielectric layer 216 through a deposition process through a photomask, and then to butt the photomask through a photolithographic etching process. The pad material layer is patterned.

Based on the above-mentioned embodiment, it can be seen that in the above-mentioned manufacturing method of the semiconductor element, since the pad layer 220 is formed after the light-shielding structure 214 is formed, it is possible to prevent the manufacturing process (such as etching process) for forming the light-shielding structure 214 from being formed. process) damages the pad layer 220 . In addition, the photomask can reduce the number of photomasks required for the manufacturing process of the semiconductor element by using the method for manufacturing the semiconductor element in the above embodiment, thereby reducing the production cost.

In addition, the semiconductor device in the above embodiments is described by taking a back side illumination image sensing device as an example, but the present invention is not limited thereto. The above-mentioned method for manufacturing a semiconductor device can also be applied to making a front side illumination image sensor device. The differences between the front-illuminated image sensor and the back-illuminated image sensor are as follows. In the front-illuminated image sensor device, the conductor layer connected to the pad layer may be the uppermost conductor layer on the front surface of the substrate.

For example, in an embodiment where the semiconductor device is a front-side illuminated image sensor device, the manufacturing method of the semiconductor device includes the following steps. Provide the base. There is a dielectric layer structure on the substrate, and a conductive layer (eg, an uppermost conductive layer) in the dielectric layer structure. A first opening exposing the conductor layer is formed in the dielectric layer structure. A light blocking structure is formed on the dielectric layer structure. A dielectric layer covering the light-shielding structure and filling the first opening is formed. A second opening exposing the conductor layer is formed in the dielectric layer. A pad layer electrically connected to the conductor layer is formed in the second opening.

To sum up, in the manufacturing method of the semiconductor element in the above embodiment, since the pad layer is formed after the light blocking structure is formed, damage to the pad layer due to the fabrication process for forming the light blocking structure can be prevented. In addition, the photomask can reduce the number of photomasks required for the manufacturing process of the semiconductor element by using the method for manufacturing the semiconductor element in the above embodiment, thereby reducing the production cost.

Although the present invention has been disclosed in conjunction with the above embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention should be defined by the appended claims.

Claims (9)

1. A semiconductor assembly, characterized in that, comprising: a base having a first face, a second face opposite the first face, and a first opening; a first dielectric layer structure disposed on the first surface and having a conductor layer and a second opening, wherein the second opening exposes the conductor layer and is connected to the first opening; a second dielectric layer structure disposed on the second surface and having a third opening, wherein the third opening exposes a portion of the substrate and is connected to the first opening; a first light blocking structure disposed on the second dielectric layer structure; the second light blocking structure is arranged on the side wall of the third opening; a dielectric layer disposed on the light blocking structure and in the third opening, and having a fourth opening connected to the first opening; and The pad layer is disposed on the dielectric layer and in the fourth opening, and is electrically connected to the conductor layer. 2. The semiconductor component according to claim 1, wherein the first light blocking structure is not connected to the second light blocking structure. 3. The semiconductor device according to claim 1, wherein the first light blocking structure and the second light blocking structure are metal grids. 4. The semiconductor device according to claim 1, wherein the second light-shielding structure and the pad layer are separated from each other. 5. The semiconductor device as claimed in claim 1, wherein the second light blocking structure and the dielectric layer are disposed on the portion of the substrate. 6. The semiconductor device according to claim 1, wherein the dielectric layer in the third opening covers the second light blocking structure. 7. The semiconductor device as claimed in claim 1, wherein the pad layer is further disposed in the first opening and the second opening. 8. The semiconductor component according to claim 1, wherein the second dielectric layer structure further has a fifth opening, the fifth opening exposes part of the substrate, and the semiconductor component further comprises : The third light blocking structure is arranged in the fifth opening. 9. The semiconductor component according to claim 8, wherein the first light blocking structure is connected to the third light blocking structure.

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