Semiconductor structure, redistribution layer structure and manufacturing method thereof

Abstract

The present disclosure relates to a redistribution layer structure, a method for manufacturing the redistribution layer structure, and a semiconductor structure. The redistribution layer structure includes: a redistribution layer, which is arranged on a substrate, and the redistribution layer includes a pad portion and a wire portion connected to the pad portion; wherein the thickness of the pad portion is greater than the thickness of the wire portion. The redistribution layer structure provided by the present disclosure has a pad portion that is thicker than the wire portion. The thicker pad portion can provide more impact buffer zones when packaging gold or copper wire bonding to avoid the substrate from being broken by force, and also avoids the problem of increasing the parasitic capacitance between wires when increasing the thickness of the pad portion.

Description

Technical Field

[0001] The present disclosure relates to the field of semiconductor technology, and in particular to a redistribution layer structure, a method for manufacturing the redistribution layer structure, and a semiconductor structure. Background Art

[0002] Re-distribution Layer (RDL) is to change the contact position (I / O pad) of the original integrated circuit (IC) through the wafer-level metal wiring process and bump process, so that the IC can be suitable for different packaging forms. The wafer-level metal wiring process is to coat an insulating protective layer on the IC, and then define the new wire pattern by exposure and development, and then use electroplating technology to make new metal circuits to connect the original aluminum pads and new bumps or copper pads to achieve the purpose of circuit redistribution.

[0003] In the related art, when the redistribution layer of the aluminum pad is processed by the gold / copper solder ball process of wire bonding, the aluminum pad of the redistribution layer that is not thick enough will often be squeezed outward from the center of the pad by the gold or copper solder ball. The solder ball may directly hit the substrate, causing the substrate to crack or deform, resulting in IC short circuit failure.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The object of the present disclosure is to provide a redistribution structure capable of providing more bump buffer areas when packaging copper wires.

[0006] According to one aspect of the present disclosure, a redistribution layer structure is provided. The redistribution layer structure comprises:

[0007] A redistribution layer is disposed on a substrate, wherein the redistribution layer includes a pad portion and a wire portion connected to the pad portion;

[0008] Wherein, the thickness of the pad portion is greater than the thickness of the wire portion.

[0009] In an exemplary embodiment of the present disclosure, the pad portion includes a pad body portion and a welding portion disposed on a side of the pad body portion away from the substrate.

[0010] In an exemplary embodiment of the present disclosure, the pad portion formed by the pad body portion and the welding portion is in a boss shape, and the length and width of the orthographic projection of the pad body portion are greater than the length and width of the orthographic projection of the welding portion.

[0011] In an exemplary embodiment of the present disclosure, a side edge of the welding portion and a side edge of the pad body portion have a preset distance, and the preset distance is between 0.5 μm and 3 μm.

[0012] In an exemplary embodiment of the present disclosure, the pad body portion and the welding portion are an integral structure.

[0013] In an exemplary embodiment of the present disclosure, the thickness of the wire portion is the same as the thickness of the pad body portion.

[0014] In an exemplary embodiment of the present disclosure, the thickness of the welding portion is between 1 μm and 2.5 μm.

[0015] In an exemplary embodiment of the present disclosure, the shape of the orthographic projection of the welding portion is a rectangle, a hexagon, an octagon, a circle or an ellipse, the shape of the orthographic projection of the welding pad body is a rectangle, a hexagon, an octagon, a circle or an ellipse, and the shape of the orthographic projection of the welding pad body is the same as or different from the shape of the orthographic projection of the welding portion.

[0016] In an exemplary embodiment of the present disclosure, the side cross-sectional shape of the welding portion and the pad body portion is rectangular or trapezoidal.

[0017] In an exemplary embodiment of the present disclosure, the side cross-sectional shape of the welding portion is trapezoidal, including a top surface, a bottom surface and a side surface, the top surface is a side surface away from the substrate, the area of ​​the top surface is smaller than the area of ​​the bottom surface, the side cross-sectional shape of the welding pad body is rectangular, and the bottom surface of the welding portion is connected to the welding pad body.

[0018] In an exemplary embodiment of the present disclosure, the side cross-sectional shape of the pad body is trapezoidal, including a top surface, a bottom surface and a side surface, the top surface is a side surface away from the substrate, the area of ​​the top surface is smaller than the area of ​​the bottom surface, the side cross-sectional shape of the welding portion is rectangular, and the welding portion is connected to the top surface of the pad body.

[0019] In an exemplary embodiment of the present disclosure, the material of the welding portion is the same as the material of the pad body.

[0020] In an exemplary embodiment of the present disclosure, the material of the wire portion is the same as the material of the pad body portion.

[0021] In an exemplary embodiment of the present disclosure, the redistribution layer structure further includes:

[0022] A passivation layer is disposed on a side of the redistribution layer away from the substrate;

[0023] A protective layer, disposed on a side of the passivation layer away from the substrate;

[0024] The protective layer has an opening to expose a side of the welding portion away from the substrate;

[0025] A side surface of the protection layer away from the substrate protrudes from a side surface of the welding portion away from the substrate.

[0026] In an exemplary embodiment of the present disclosure, the redistribution layer structure further includes:

[0027] A protection layer, disposed on a side of the redistribution layer away from the substrate;

[0028] The protective layer has an opening to expose a side of the welding portion away from the substrate;

[0029] A side surface of the protection layer away from the substrate protrudes from a side surface of the welding portion away from the substrate.

[0030] According to another aspect of the present disclosure, a method for manufacturing a redistribution layer structure is provided. The manufacturing method comprises:

[0031] providing a substrate;

[0032] forming a redistribution layer on the substrate, wherein the redistribution layer comprises a pad portion and a wire portion connected to the pad portion;

[0033] Wherein, the thickness of the pad portion is greater than the thickness of the wire portion.

[0034] In an exemplary embodiment of the present disclosure, forming a redistribution layer on the substrate includes:

[0035] forming a metal layer on the substrate;

[0036] forming a first photoresist layer matching the shape of the pad portion on a side of the metal layer away from the substrate;

[0037] Etching the area of ​​the metal layer not covered by the first photoresist layer so that the thickness of the metal layer at the pad portion is greater than that of other areas;

[0038] forming a second photoresist layer of a preset pattern on a side of the metal layer away from the substrate;

[0039] The area of ​​the metal layer not covered by the second photoresist layer is etched so that the metal layer forms the pad portion and the wire portion.

[0040] In an exemplary embodiment of the present disclosure, the manufacturing method further includes:

[0041] forming a passivation layer on a side of the redistribution layer away from the substrate;

[0042] forming a protective layer on a side of the passivation layer away from the substrate;

[0043] The protection layer is etched to expose the welding portion from the passivation layer.

[0044] In an exemplary embodiment of the present disclosure, the manufacturing method further includes:

[0045] forming a protective layer on a side of the redistribution layer away from the substrate;

[0046] The protective layer is etched to expose the welding portion from the protective layer.

[0047] According to another aspect of the present disclosure, a semiconductor structure is provided, which includes the above-mentioned redistribution layer structure.

[0048] The redistribution layer structure provided by the present disclosure avoids the problem of increasing the parasitic capacitance between wires when the thickness of the redistribution layer is increased. In the redistribution layer structure provided by the present disclosure, the pad portion that is thicker than the wire portion can provide more impact buffers when packaging gold or copper wires to avoid the substrate insulation layer from being broken by force, or the bottom metal wire of the pad portion from being compressed and deformed to cause a short circuit. The wire portion that is thinner than the pad portion can reduce the parasitic capacitance effect between the circuits and improve the IC performance to meet the high-frequency working requirements.

[0049] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0051] Figure 1 A schematic diagram of a redistribution layer structure provided in accordance with an embodiment of the present disclosure;

[0052] Figure 2 A top view of a redistribution layer structure provided for another embodiment of the present disclosure;

[0053] Figure 3 A step diagram of a method for manufacturing a redistribution layer structure provided by an embodiment of the present disclosure;

[0054] Figure 4A schematic diagram of a redistribution layer structure after step 122 of the manufacturing method provided in one embodiment of the present disclosure is completed;

[0055] Figure 5 A schematic diagram of a redistribution layer structure after step 123 of the manufacturing method provided in one embodiment of the present disclosure is completed;

[0056] Figure 6 A schematic diagram of a redistribution layer structure after step 124 of the manufacturing method provided in one embodiment of the present disclosure is completed;

[0057] Figure 7 A schematic diagram of a redistribution layer structure after step 125 of the manufacturing method provided in one embodiment of the present disclosure is completed;

[0058] Figure 8 A schematic diagram of a redistribution layer structure after step 126 of the manufacturing method provided in one embodiment of the present disclosure is completed;

[0059] Fig. 9 A schematic diagram of a redistribution layer structure after step 128 of the manufacturing method provided in one embodiment of the present disclosure is completed;

[0060] Fig.10 A schematic diagram of a redistribution layer structure after step 127' of a manufacturing method provided in another embodiment of the present disclosure is completed;

[0061] Fig.11 A side cross-sectional view of a redistribution layer structure provided for another embodiment of the present disclosure;

[0062] Fig.12 A side cross-sectional view of a redistribution layer structure provided according to yet another embodiment of the present disclosure. DETAILED DESCRIPTION

[0063] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted.

[0064] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of the illustration to another component, these terms are used in this specification only for convenience, such as according to the orientation of the examples described in the drawings. It is understood that if the device of the illustration is turned upside down, the component described as "upper" will become the component "lower". When a structure is "on" other structures, it may mean that the structure is formed integrally on the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through another structure.

[0065] The terms "a", "an", "the", "said" and "at least one" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express an open-ended inclusive meaning and mean that additional elements / components / etc. may exist in addition to the listed elements / components / etc.; the terms "first", "second", etc. are used merely as labels and are not intended to limit the quantity of their objects.

[0066] In the related technology, when the aluminum redistribution layer is subjected to the copper wire bonding process, the aluminum pad of the redistribution layer that is not thick enough is often squeezed outward from the center of the pad by the copper solder ball. The copper solder ball may directly hit the substrate, causing the substrate to crack or deform, resulting in IC short circuit failure.

[0067] The present disclosure provides a redistribution layer structure, such as Figure 1 , Figure 2 and Figure 7 As shown, it includes a redistribution layer 105 disposed on a substrate 111 , and the redistribution layer 105 includes a pad portion 104 and a wire portion 103 connected to the pad portion 104 ; wherein the thickness of the pad portion 104 is greater than the thickness of the wire portion 103 .

[0068] The redistribution layer structure provided by the present disclosure avoids the problem of increasing the parasitic capacitance between wires when the thickness of the redistribution layer is increased. In the redistribution layer structure provided by the present disclosure, the pad portion that is thicker than the wire portion can provide more impact buffers when packaging gold or copper wires to avoid the substrate insulation layer from being broken by force, or the bottom metal wire of the pad portion from being compressed and deformed to cause a short circuit. The wire portion that is thinner than the pad portion can reduce the parasitic capacitance effect between the circuits and improve the IC performance to meet the high-frequency working requirements.

[0069] The following describes in detail the various parts of the redistribution layer structure of the embodiment of the present disclosure in conjunction with the accompanying drawings:

[0070] The pad portion 104 includes a pad body portion 102 and a soldering portion 101 disposed on a side of the pad body portion 102 away from the substrate.

[0071] Furthermore, the pad portion 104 formed by the pad body portion 102 and the welding portion 101 is in the shape of a boss, and the length and width of the orthographic projection of the pad body portion 102 are greater than the length and width of the orthographic projection of the welding portion 101. The welding portion 101 on the side away from the substrate forms a step surface with the pad body portion 102 located below the welding portion 101, forming a pad portion 104 with a boss-shaped structure. The side wall of the welding portion 101 on the step surface can be covered by photoresist to form protection for the side wall of the welding portion 101, so as to avoid the etching liquid from etching the side wall of the welding portion 101 when the pad portion 104 and the wire portion 103 are formed by etching, and to avoid the etching liquid from being unable to etch through the wire portion 103 adjacent to the pad portion 104, causing a short circuit between the wire portion 103 and the pad portion 104. In the redistribution layer structure disclosed in the present invention, one side of the pad body 102 away from the substrate side is in direct contact with one side of the welding portion 101 located above the side of the pad body 102, and there is no dielectric layer or isolation layer between the two side surfaces, that is, the pad body 102 and the welding portion 101 are an integral structure, so that the pad body 102 can provide sufficient current to connect to the welding portion 101, thereby avoiding IC signal transmission delay.

[0072] In one embodiment of the present disclosure, the side of the welding portion 101 has a preset distance from the side of the pad body 102, so that the orthographic projection of the welding portion 101 on the pad body 102 is located within the edge of the pad body 102. The preset distance is the width of the step surface, and the preset distance is between 0.5 μm and 3 μm. For example, the preset distance can be 1 μm, 1.5 μm, 2 μm or 2.5 μm. The preset distance is based on the width of the side wall of the welding portion 101 covered by the photoresist, and the present disclosure does not make any special restrictions on this.

[0073] In one embodiment of the present disclosure, Figure 1 and Figure 7 As shown, the thickness of the wire portion 103 is the same as the thickness of the pad body portion 102, that is, the surface of the wire portion 103 is flush with the step surface. In other embodiments of the present disclosure, the thickness of the wire portion 103 may be greater than the thickness of the pad body portion 102, or less than the thickness of the pad body portion 102, that is, the height of the surface of the wire portion 103 away from the substrate may be higher than the height of the step surface, or may be lower than the height of the step surface, and the present disclosure does not limit this.

[0074] In one embodiment of the present disclosure, the thickness of the pad portion 104 is between 3 μm and 6 μm, and the thickness of the welding portion 101 is between 1 μm and 2.5 μm. For example, the thickness of the pad portion 104 may be 3.5 μm, 4 μm, 4.5 μm, 5 μm or 5.5 μm, and the thickness of the welding portion 101 may be 1.5 μm or 2 μm. The present disclosure does not limit this.

[0075] In one embodiment of the present disclosure, the material of the pad body 102 is a metal conductive material. For example, the material of the pad body 102 can be one of copper, aluminum, tungsten, titanium, or an alloy of the above materials. The pad body 102 can be composed of a layer of metal conductive material, or can be composed of multiple layers of different metal conductive materials stacked together. The present disclosure does not limit this.

[0076] In one embodiment of the present disclosure, the material of the welding portion 101 and the material of the pad body 102 can be the same, so that the welding portion 101 and the pad body 102 are easy to prepare in the same process, that is, the pad body 102 and the welding portion 101 are an integrated structure. In another embodiment of the present disclosure, the material of the welding portion 101 and the material of the pad body 102 can be different. The welding portion 101 can be composed of a layer of metal conductive material, or it can be composed of multiple layers of different metal conductive materials stacked. The present disclosure does not limit this.

[0077] In one embodiment of the present disclosure, the material of the wire portion 103 and the material of the pad body portion 102 may be the same, so that the wire portion 103 and the pad body portion 102 are conveniently prepared in the same process. In another embodiment of the present disclosure, the material of the wire portion 103 and the material of the pad body portion 102 may be different. The present disclosure does not limit this.

[0078] The shape of the orthographic projection of the welding portion 101 may be a rectangle, a hexagon, an octagon, a circle, an ellipse or other shapes that can be prepared by a patterning process, so as not to have a negative impact on other devices and to be able to meet the requirements of effective contact with the package wire bonding gold or copper solder balls. The shape of the pad body 102 may be the same as or different from the shape of the welding portion 101, so as to be within the preset distance range between the edge of the orthographic projection of the pad body 102 and the edge of the orthographic projection of the welding portion 101. For example, the orthographic projection of the welding portion 101 is in the shape of a rectangle, and the shape of the pad body 102 is in the shape of a rectangle, or the orthographic projection of the welding portion 101 is in the shape of a rectangle, and the shape of the orthographic projection of the pad body 102 is in the shape of a hexagon. The present disclosure does not limit this.

[0079] The side cross-sectional shapes of the soldering portion 101 and the pad body portion 102 may be rectangular or trapezoidal, etc. The side cross-sectional shape of the soldering portion 101 may be the same as or different from the side cross-sectional shape of the pad body portion 102 .

[0080] In one embodiment of the present disclosure, Figure 7 As shown, the side cross-sectional shapes of the welding portion 101 and the welding pad body 102 are both rectangular. The use of the welding portion 101 and the welding pad body 102 in a rectangular table shape reduces the process difficulty and facilitates manufacturing.

[0081] In another embodiment of the present disclosure, Fig.11 As shown, the side cross-sectional shape of the welding part 101 is trapezoidal, including a top surface, a bottom surface and a side surface, the side surface is used to connect the top surface and the bottom surface, the top surface is a side surface away from the substrate, and the area of ​​the top surface is smaller than the area of ​​the bottom surface. The side cross-sectional shape of the pad body 102 is rectangular, and the bottom surface of the welding part 101 is connected to the pad body 102. The welding part 101 adopts a trapezoidal shape, which can improve the support of the welding part 101 and reduce the impact damage of the gold or copper solder ball on the welding part 101 during the packaging wire bonding.

[0082] In another embodiment of the present disclosure, Fig.12 As shown, the side cross-sectional shape of the pad body 102 is trapezoidal, including a top surface, a bottom surface and a side surface, the side surface is used to connect the top surface and the bottom surface, the top surface is a side surface away from the substrate, and the area of ​​the top surface is smaller than the bottom surface. The side cross-sectional shape of the welding portion 101 is rectangular, and the welding portion 101 is connected to the top surface of the pad body 102. The pad body 102 adopts a trapezoidal table shape, which can improve the support of the pad body 102 to the welding portion 101 and reduce the impact damage of the gold or copper solder ball on the welding portion 101 and the pad body 102 during the packaging wire bonding.

[0083] In one embodiment of the present disclosure, the redistribution layer structure further includes: a passivation layer and a protective layer. Fig. 9 As shown, a passivation layer 116 is provided on the side of the redistribution layer 105 away from the substrate 111, and the passivation layer 116 is flush with the side of the pad portion 104 away from the substrate 111. In another embodiment, the passivation layer 116 may be lower or higher than the pad portion 104. The material of the passivation layer 116 is a dielectric material, and the material of the passivation layer 116 may be one or more combinations of silicon oxide, silicon nitride or silicon oxynitride materials. It is understandable that the passivation layer may be composed of a layer of dielectric material, or may be composed of multiple layers of dielectric materials stacked together, and the present disclosure does not limit this. Further, a protective layer 117 is provided on the side of the passivation layer 116 away from the substrate 111 to form protection for the passivation layer 116 below. In one embodiment of the present disclosure, the material of the protective layer 117 may be polyimide. The protective layer 117 has an opening, which enables the welding portion 101 to be exposed from the protective layer 117. A side surface of the protection layer 117 away from the substrate 111 protrudes from a side surface of the soldering portion 101 away from the substrate 111 .

[0084] In another embodiment of the present disclosure, the redistribution layer structure further includes: a protective layer. Fig.10As shown, a protective layer 117 is formed on the side of the redistribution layer 105 away from the substrate 111, and the protective layer 117 has an opening, which enables the soldering portion 101 to be exposed from the protective layer 117. The side of the protective layer 117 away from the substrate 111 protrudes from the side of the soldering portion 101 away from the substrate 111. In one embodiment of the present disclosure, the material of the protective layer can be polyimide.

[0085] In the redistribution layer structure of the present disclosure, other shapes of the welding portion 101 and the welding pad body 102 may also be selected, and the present disclosure does not impose any restrictions on this. Any changes in the shapes of the welding portion 101 and the welding pad body 102 fall within the protection scope of the present disclosure.

[0086] The present disclosure also provides a method for manufacturing a redistribution layer structure. The method comprises the steps of:

[0087] Step S110, providing a substrate;

[0088] Step S120, forming a redistribution layer on the substrate, wherein the redistribution layer includes a pad portion and a wire portion connected to the pad portion;

[0089] The thickness of the pad portion is greater than the thickness of the wire portion.

[0090] The manufacturing method of the redistribution layer structure disclosed in the present invention provides a redistribution layer structure that avoids the problem of increasing parasitic capacitance between wires when increasing the thickness of the pad portion. The pad portion that is thicker than the wire portion can provide more impact buffers when packaging gold or copper wires to avoid the substrate insulation layer from being broken by force, or the bottom metal wire from being compressed and deformed to cause a short circuit. In addition, the wire portion that is thinner than the pad portion can reduce the parasitic capacitance effect between the circuits and improve IC performance to meet high-frequency working requirements.

[0091] Combine the following Figure 3-Figure 10 The manufacturing method of the redistribution layer structure according to the embodiment of the present disclosure is described in detail:

[0092] Step S110: providing a substrate.

[0093] In an embodiment of the present disclosure, the substrate 111 may be a silicon substrate such as a silicon epitaxial wafer or silicon on an insulating layer, or a substrate of other semiconductor materials such as GaN, and the substrate 111 may be an intrinsic semiconductor substrate, or an N-type doped or P-type doped semiconductor substrate, and the substrate 111 may include one or more of a dielectric layer, an insulating layer, or a passivation layer. The present disclosure does not limit this.

[0094] Step S120: forming a redistribution layer on the substrate.

[0095] In step S120, forming a redistribution layer on the substrate may include:

[0096] Step S121, forming a metal layer on a substrate.

[0097] A metal layer 112 of a preset thickness can be formed on the substrate 111 by physical vapor deposition, electroplating, etc. For example, the thickness of the metal layer 112 is between 3 μm and 6 μm. The material of the metal layer 112 is a conductive material, for example, the material of the metal layer can be one of copper, aluminum, tungsten, titanium, or an alloy of the above materials. This disclosure is not limited to this.

[0098] Step S122 , forming a first photoresist layer matching the shape of the pad portion on a side of the metal layer away from the substrate.

[0099] like Figure 4 As shown, a first photoresist layer 113 is formed on a side of the metal layer 112 away from the substrate 111 by spraying.

[0100] Step S123 , etching the area of ​​the metal layer not covered by the first photoresist layer, so that the thickness of the metal layer at the pad portion is greater than the thickness of other areas.

[0101] like Figure 5 As shown, the areas of the metal layer 112 not covered by the first photoresist layer 113 are exposed and developed, and then etched by wet etching, dry etching or plasma etching to reduce the thickness of these areas on the metal layer 112. In one embodiment of the present disclosure, the thickness of the metal layer 112 is 3μm-6μm, and the thickness of the thinned area is 2μm-5μm. For example, the thickness of the metal layer is 3.5μm, 4μm, 4.5μm, 5μm or 5.5μm, and the thickness of the thinned area is 2.5μm, 3μm or 3.5μm, 4μm or 4.5μm.

[0102] Step S124 , forming a second photoresist layer with a preset pattern on a side of the metal layer away from the substrate.

[0103] A second photoresist layer 115 is formed on the metal layer 112 by spraying.

[0104] The side walls of the welding portion 101 on the step surface are covered by the second photoresist 115, thereby protecting the side walls of the welding portion 101 and preventing the etching liquid from etching the side walls of the welding portion 101 when the welding pad portion and the wire portion are formed by etching, thereby preventing the etching liquid from being unable to etch through the wire portion 103 adjacent to the welding pad portion 104, causing a short circuit between the wire portion 103 and the welding pad portion 104.

[0105] Step S125 , etching the area of ​​the metal layer not covered by the second photoresist layer, so that the metal layer forms the pad portion and the wire portion.

[0106] The portion of the metal layer 112 not covered by the second photoresist layer 115 is etched to form Figure 7 The metal layer of the pattern shown enables the metal layer 112 to form a welding portion 101 , a pad body portion 102 and a wire portion 103 .

[0107] In one embodiment of the present disclosure, the side of the soldering portion 101 is at a preset distance from the side of the soldering pad body 102, so that the orthographic projection of the soldering portion 101 on the soldering pad body 102 is located within the edge of the soldering pad body 102. The preset distance is between 0.5 μm and 3 μm. For example, the preset distance may be 1 μm, 1.5 μm, 2 μm or 2.5 μm.

[0108] In one embodiment of the present disclosure, the thickness of the formed welding portion 101 is between 1 μm and 2.5 μm. For example, the thickness of the welding portion 101 may be 1.5 μm or 2 μm.

[0109] In one embodiment of the present disclosure, the method for manufacturing the redistribution layer structure further includes:

[0110] Step S126 , forming a passivation layer on a side of the redistribution layer away from the substrate.

[0111] like Figure 8 As shown, the passivation layer 116 is flush with the side of the pad portion away from the substrate 111. Of course, the passivation layer 116 may be higher than the pad portion 104, or lower than the pad portion 104. The material of the passivation layer is a dielectric material, and the material of the passivation layer may be one or more combinations of silicon oxide, silicon nitride or silicon oxynitride materials. It is understandable that the passivation layer may be composed of a layer of dielectric material, or may be composed of multiple layers of dielectric materials stacked together. The present disclosure does not limit this.

[0112] Step S127 , forming a protective layer on a side of the passivation layer away from the substrate.

[0113] A protection layer 117 is formed on a side of the passivation layer 116 away from the substrate 111 to protect the underlying passivation layer. In one embodiment of the present disclosure, the material of the protection layer may be polyimide.

[0114] Step S128 , etching the protective layer to form an opening so that the welding portion 101 is exposed from the protective layer.

[0115] like Fig. 9 As shown, a photoresist layer can be provided, and then an opening can be formed by masking, exposure, etching and other processes to expose the welding portion 111 from the passivation layer 117. In one embodiment of the present disclosure, the side of the protective layer 117 away from the substrate 111 protrudes from the side of the welding portion 101 away from the substrate 111.

[0116] In another embodiment of the present disclosure, the method for manufacturing the redistribution layer structure further includes:

[0117] Step S126', forming a protection layer on a side of the redistribution layer away from the substrate.

[0118] A protection layer 117 is directly formed on the side of the redistribution layer away from the substrate 111 to protect the redistribution layer. In one embodiment of the present disclosure, the material of the protection layer may be polyimide.

[0119] Step S127 ′, etching the protective layer to form an opening so that the welding portion 101 is exposed from the protective layer.

[0120] like Fig.10 As shown, a photoresist layer can be provided, and then an opening can be formed through masking, exposure, etching and other processes to expose the welding portion 101 from the protective layer 117. In one embodiment of the present disclosure, a side of the protective layer 117 away from the substrate 111 protrudes from a side of the welding portion 101 away from the substrate 111.

[0121] The present disclosure also provides a semiconductor structure. The semiconductor structure includes the redistribution layer structure provided in the above embodiment. Those skilled in the art should understand that the semiconductor structure also has the technical effect of the above redistribution layer structure. For example, it can be a chip, memory, processor, or other integrated circuit including the semiconductor structure.

[0122] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A redistribution layer structure, characterized in that: include: A redistribution layer is disposed on a substrate, wherein the redistribution layer includes a pad portion and a wire portion connected to the pad portion; Wherein, the thickness of the pad portion is greater than the thickness of the wire portion; The pad portion includes a pad body portion and a welding portion arranged on a side of the pad body portion away from the substrate; the pad portion formed by the pad body portion and the welding portion is in a boss shape, and the length and width of the orthographic projection of the pad body portion are greater than the length and width of the orthographic projection of the welding portion.

2. The redistribution layer structure according to claim 1, characterized in that: A side edge of the welding portion and a side edge of the pad body have a preset distance, and the preset distance is between 0.5 μm and 3 μm.

3. The redistribution layer structure according to claim 1, characterized in that: The pad body and the welding portion are an integrated structure.

4. The redistribution layer structure according to claim 1, characterized in that: The thickness of the wire portion is the same as the thickness of the pad body portion.

5. The redistribution layer structure according to claim 1, characterized in that: The thickness of the welding portion is between 1 μm and 2.5 μm.

6. The redistribution layer structure according to claim 1, characterized in that: The orthographic projection of the welding portion is in the shape of a rectangle, hexagon, octagon, circle or ellipse, the orthographic projection of the welding pad body is in the shape of a rectangle, hexagon, octagon, circle or ellipse, and the orthographic projection of the welding pad body is the same as or different from the orthographic projection of the welding portion.

7. The redistribution layer structure according to claim 1, characterized in that: The side cross-sectional shapes of the welding portion and the pad body are rectangular or trapezoidal.

8. The redistribution layer structure according to claim 7, characterized in that: The side cross-sectional shape of the welding portion is trapezoidal, including a top surface, a bottom surface and a side surface, the top surface is a side surface away from the substrate, the area of ​​the top surface is smaller than the area of ​​the bottom surface, the side cross-sectional shape of the welding pad body is rectangular, and the bottom surface of the welding portion is connected to the welding pad body.

9. The redistribution layer structure according to claim 7, characterized in that: The side cross-sectional shape of the pad body is trapezoidal, including a top surface, a bottom surface and a side surface, the top surface is a side surface away from the substrate, the area of ​​the top surface is smaller than the area of ​​the bottom surface, the side cross-sectional shape of the welding portion is rectangular, and the welding portion is connected to the top surface of the pad body.

10. The redistribution layer structure according to claim 1, characterized in that: The material of the welding portion is the same as that of the pad body.

11. The redistribution layer structure according to claim 1, characterized in that: The material of the lead portion is the same as that of the pad body portion.

12. The redistribution layer structure according to claim 1, characterized in that: The redistribution layer structure further includes: A passivation layer is disposed on a side of the redistribution layer away from the substrate; A protective layer, disposed on a side of the passivation layer away from the substrate; The protective layer has an opening to expose a side of the welding portion away from the substrate; A side surface of the protection layer away from the substrate protrudes from a side surface of the welding portion away from the substrate.

13. The redistribution layer structure according to claim 1, characterized in that: The redistribution layer structure further includes: A protection layer, disposed on a side of the redistribution layer away from the substrate; The protective layer has an opening to expose a side of the welding portion away from the substrate; A side surface of the protection layer away from the substrate protrudes from a side surface of the welding portion away from the substrate.

14. A method for manufacturing a redistribution layer structure, characterized in that: include: providing a substrate; forming a redistribution layer on the substrate, wherein the redistribution layer comprises a pad portion and a wire portion connected to the pad portion; Among them, the thickness of the pad part is greater than the thickness of the wire part; the pad part includes a pad body part and a welding part arranged on the side of the pad body part away from the substrate; the pad part formed by the pad body part and the welding part is in a boss shape, and the length and width of the orthographic projection of the pad body part are greater than the length and width of the orthographic projection of the welding part.

15. The method for manufacturing a redistribution layer structure according to claim 14, characterized in that: Forming a redistribution layer on the substrate comprises: forming a metal layer on the substrate; forming a first photoresist layer matching the shape of the pad portion on a side of the metal layer away from the substrate; Etching the area of ​​the metal layer not covered by the first photoresist layer so that the thickness of the metal layer at the pad portion is greater than that of other areas; forming a second photoresist layer of a preset pattern on a side of the metal layer away from the substrate; The area of ​​the metal layer not covered by the second photoresist layer is etched so that the metal layer forms the pad portion and the wire portion.

16. The method for manufacturing a redistribution layer structure according to claim 14, characterized in that: The manufacturing method of the redistribution layer structure further comprises: forming a passivation layer on a side of the redistribution layer away from the substrate; forming a protective layer on a side of the passivation layer away from the substrate; The protection layer is etched to expose the welding portion from the passivation layer.

17. The method for manufacturing a redistribution layer structure according to claim 14, characterized in that: The manufacturing method of the redistribution layer structure further comprises: forming a protective layer on a side of the redistribution layer away from the substrate; The protective layer is etched to expose the welding portion from the protective layer.

18. A semiconductor structure, characterized in that: The redistribution layer structure comprises the redistribution layer structure as described in any one of claims 1 to 13.

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