A method for manufacturing a semi-finished wafer and a semi-finished wafer

Abstract

The present invention provides a method for manufacturing a semi-finished wafer and a semi-finished wafer. The method for manufacturing a semi-finished wafer includes: providing a substrate, forming a peeling layer on the substrate; forming a first metal layer on the peeling layer; applying a first protective layer on the first metal layer, the first protective layer covering the portion of the first metal layer adjacent to its outer edge; applying a second metal layer on the first protective layer, and the second metal layer simultaneously covers the portion of the first metal layer exposed outside the first protective layer; applying a second protective layer on the second metal layer to obtain a semi-finished wafer. After the semi-finished wafer manufactured by the method for manufacturing a semi-finished wafer provided by the present invention is processed into a finished wafer through necessary treatment, when wafer-level packaging is performed, the peeling layer and the metal layer thereon will not have the problem of regional peeling of the edge due to insufficient adhesion of the substrate, thereby avoiding abnormal edge finding of subsequent operation machines.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor manufacturing, and in particular relates to a manufacturing method of a semi-finished wafer and a semi-finished wafer. Background Art

[0002] Wafer-level packaging is a packaging method that uses wafers as processing objects, performs all packaging and testing on the wafers at the same time, and finally cuts them into individual devices, which are directly attached to the substrate or printed circuit board when used. With the increasing integration of devices and the decreasing feature size of devices, the application of wafer-level packaging is becoming more and more extensive.

[0003] In the prior art, due to the process requirements, the manufacturing process of the wafer is: first, a layer of stripping agent is applied on the provided substrate to form a stripping layer, and then a metal layer and a protective layer are applied on the formed stripping layer at intervals, and then necessary processes such as edge etching and cleaning are performed to finally obtain the wafer. However, when it is used for wafer-level packaging, it is found that during the process of demolding the die to form the packaged wafer, the wafer is prone to regional stripping of the stripping layer and the edge of the metal layer thereon due to insufficient adhesion of the substrate, which will also cause abnormal edge finding of the subsequent operation machine. Summary of the invention

[0004] In view of the problems existing in the above-mentioned prior art, the main purpose of the present invention is to provide a method for manufacturing a semi-finished wafer and a semi-finished wafer to solve one or more of the above-mentioned prior art problems.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The present invention provides a method for manufacturing a semi-finished wafer, the method comprising:

[0007] Providing a substrate, and forming a peeling layer on the substrate;

[0008] forming a first metal layer on the peeling layer;

[0009] Applying a first protective layer on the first metal layer, wherein the first protective layer covers a portion of the first metal layer adjacent to its outer edge;

[0010] Applying a second metal layer on the first protective layer, wherein the second metal layer simultaneously covers the portion of the first metal layer exposed outside the first protective layer;

[0011] A second protective layer is applied on the second metal layer to obtain a semi-finished wafer.

[0012] As a further description of the above technical solution, in the step of "applying a first protective layer on the first metal layer, wherein the first protective layer covers a portion of the first metal layer adjacent to its outer edge", the method includes:

[0013] Applying a first protective layer on the first metal layer, wherein the first protective layer includes a first preset area and a second preset area;

[0014] The first protective layer in the first preset area is exposed, developed and removed, so that the first protective layer in the second preset area covers the portion of the first protective layer adjacent to its outer edge.

[0015] As a further description of the above technical solution, the first protective layer is a non-conductive film layer.

[0016] As a further description of the above technical solution, the applied first protective layer has a thickness ranging from 10 μm to 15 μm and a width ranging from 1 μm to 1.5 μm.

[0017] As a further description of the above technical solution, the distance between the outer edge of the first metal layer and the outer edge of the first protective layer is 2mm-3mm.

[0018] As a further description of the above technical solution, the first metal layer includes at least one of the following film layers: a titanium layer and a copper layer.

[0019] As a further description of the above technical solution, the second metal layer includes at least one of the following film layers: a titanium layer and a copper layer.

[0020] The present invention also provides a semi-finished wafer, which is manufactured using the method for manufacturing the semi-finished wafer as described above.

[0021] By means of the above technical solution, the outstanding effects of the present invention are:

[0022] 1. When using the manufacturing method of the semi-finished wafer provided by the present invention to manufacture the semi-finished wafer, the metal layer on the peeling layer is applied twice, that is, the first metal layer is first formed on the peeling layer, and then the second metal layer is applied on the first metal layer. Before applying the second metal layer, the first protective layer is applied to the part of the first metal layer near its outer edge. After the second metal layer is applied, the second metal layer will simultaneously cover the first protective layer and the part of the first metal layer exposed outside the first protective layer. Finally, the second protective layer is applied on the second metal layer to obtain the semi-finished wafer. After the semi-finished wafer is subjected to the necessary conventional processing technology to obtain the finished wafer, it is used for wafer-level packaging. In the process of demolding the die to form the packaged wafer, the first protective layer will play a role of spacing protection for the first metal layer and the peeling layer below it. The finished wafer will not have the problem of regional peeling of the peeling layer and the edge of the metal layer thereon due to insufficient adhesion of the substrate, and will not cause abnormal edge finding problems in subsequent operating machines. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the process of manufacturing a semi-finished wafer in an embodiment of the present invention;

[0024] Figure 2 Schematic diagram of the structure of a semi-finished wafer in an embodiment of the present invention.

[0025] Description of Figure Numbers:

[0026] 1. Base material; 2. Peeling layer; 3. First metal layer; 4. First protective layer; 5. Second metal layer; 6. Second protective layer. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper", "middle", "lower", "inside", "outside", "front", "back", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. The following describes an implementation method of the present invention based on its overall structure.

[0029] See also Figure 1 to Figure 2 The present invention discloses a method for manufacturing a semi-finished wafer, which comprises:

[0030] Providing a substrate 1, and forming a peeling layer 2 on the substrate 1;

[0031] forming a first metal layer 3 on the peeling layer 2;

[0032] Applying a first protective layer 4 on the first metal layer 3, wherein the first protective layer 4 covers a portion of the first metal layer 3 adjacent to its outer edge;

[0033] Applying a second metal layer 5 on the first protective layer 4, and the second metal layer 5 also covers the portion of the first metal layer 3 exposed outside the first protective layer 4;

[0034] A second protective layer 6 is applied on the second metal layer 5 to obtain a semi-finished wafer.

[0035] Compared with the prior art, the above-mentioned manufacturing method first forms a peeling layer 2 on the provided substrate 1, and then is equivalent to applying the original metal layer on the peeling layer 2 twice, that is, first forming a first metal layer 3 on the peeling layer 2, and then applying a second metal layer 5 on the first metal layer 3, and before applying the second metal layer 5, applying a first protective layer 4 to the portion of the first metal layer 3 adjacent to its own outer edge, after the second metal layer 5 is applied, the second metal layer 5 will simultaneously cover the first protective layer 4 and the portion of the first metal layer 3 exposed outside the first protective layer 4, and finally applying a second protective layer 6 on the second metal layer 5 to obtain a semi-finished wafer. After the semi-finished wafer is subjected to necessary conventional processing techniques to obtain a finished wafer, it is used for wafer-level packaging. During the process of demolding the mold to form a packaged chip, the first protective layer 4 will play a role of spacing and protection for the first metal layer 3 and the peeling layer 2 thereunder. The finished wafer will not have the problem of regional peeling of the peeling layer 2 and the edge of the metal layer thereon due to insufficient adhesion of the substrate 1, and will not cause abnormal edge-finding problems in subsequent operating machines.

[0036] Please refer to the figure. Specifically, in this embodiment, in the step of "applying a first protective layer 4 on the first metal layer 3, wherein the first protective layer 4 covers a portion of the first metal layer 3 adjacent to its outer edge", the steps include:

[0037] The first protective layer 4 is applied on the first metal layer 3 first, and the first protective layer 4 completely covers the side of the first metal layer 3 facing away from the peeling layer 2, including the first preset area and the second preset area; the first protective layer 4 is made of photosensitive material, so the first protective layer 4 in the first preset area can be exposed and developed to be removed, leaving only the second preset area of ​​the first protective layer 4, thereby covering the part of the first protective layer 4 adjacent to its own outer edge. The first preset area, i.e., the part of the first protective layer 4 corresponding to the edge of the first metal layer 3 adjacent to itself in the thickness direction, and the second preset area, i.e., the part of the first protective layer 4 except the part corresponding to the edge of the first metal layer 3 adjacent to itself in the thickness direction.

[0038] It should be understood that, in this embodiment, after the first preset area of ​​the first protective layer is subjected to the exposure, development and removal steps, a conventional adaptive cleaning process may be used to clean the first preset area of ​​the first protective layer to ensure the effectiveness of the removal.

[0039] Specifically, in this embodiment, the first protective layer 4 is a non-conductive film layer, and the second metal layer 5 and the first metal layer 3 applied thereon form a wrapping layer outside the first protective layer 4, so there will be no problem of the edge of the wafer being non-conductive during subsequent electroplating.

[0040] Specifically, in this embodiment, the thickness of the applied first protective layer 4 is 10μm, the width is 1.1μm, and the distance between the outer edge of the first protective layer and the outer edge of the first protective layer 4 is 2.5mm, so that the first protective layer 4 can play a role of spacing protection for the first metal layer 3 and the peeling layer 2 thereunder. Of course, in other embodiments, the thickness of the applied first protective layer 4 can also be set to other values ​​between 10μm-15μm, and its width can also be set to other values ​​between 1μm-1.5μm; the distance between the outer edge of the first metal layer 3 and the outer edge of the first protective layer 4 can also be set to other values ​​between 2mm-3mm.

[0041] Specifically, in the present embodiment, the first metal layer 3 is a titanium layer, and the second metal layer 5 is also a titanium layer. Of course, in other embodiments, the first metal layer 3 and the second metal layer 5 may also be a combination of one or more of the titanium layer, copper layer and other film layers. It should be understood that the first metal layer 3 and the second metal layer 5 are equivalent to the metal layers obtained by the original process, except that the first protective layer 4 is added to the parts near the outer edges of the two. Therefore, the thickness of the first metal layer 3 from the side connected to the stripping layer 2 to the side of the second metal layer 5 away from the first metal layer 3 is the same as the thickness of the metal layer without the first protective layer 4 obtained by the original process, and thus will not affect the subsequent process steps.

[0042] Specifically, the present embodiment also provides a semi-finished wafer, which is manufactured by the manufacturing method of the semi-finished wafer as described above. After undergoing the necessary conventional processing technology, a finished wafer is obtained, and then it is used for wafer-level packaging. In the process of demolding the mold to form a packaged chip, the first protective layer 4 will play a role of spacing and protection for the first metal layer 3 and the peeling layer 2 thereunder. The finished wafer will not have the problem of regional peeling of the peeling layer 2 and the edge of the metal layer thereon due to insufficient adhesion of the substrate 1, and will not cause abnormal edge finding problems in subsequent operating machines.

[0043] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any changes, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for manufacturing a semi-finished wafer, It is characterized in that include: Providing a substrate, and forming a peeling layer on the substrate; forming a first metal layer on the peeling layer; Applying a first protective layer on the first metal layer, wherein the first protective layer covers a portion of the first metal layer adjacent to its outer edge, comprises: applying a first protective layer on the first metal layer, wherein the first protective layer comprises a first preset area and a second preset area; exposing and developing the first protective layer in the first preset area to remove the first protective layer, so that the first protective layer in the second preset area covers a portion of the first metal layer adjacent to its outer edge; Applying a second metal layer on the first protective layer, wherein the second metal layer simultaneously covers the portion of the first metal layer exposed outside the first protective layer; Applying a second protective layer on the second metal layer to obtain a semi-finished wafer; The first protective layer is used to provide spacing protection for the first metal layer and the peeling layer, so as to avoid edge regional peeling of the peeling layer and the metal layer thereon due to insufficient adhesion of the substrate during the molding and demolding process; The first protective layer is a non-conductive film layer; The first protective layer applied has a thickness ranging from 10 μm to 15 μm and a width ranging from 1 μm to 1.5 μm; The distance between the outer edge of the first metal layer and the outer edge of the first protective layer is 2 mm-3 mm.

2. The method for manufacturing a semi-finished wafer according to claim 1, It is characterized in that The first metal layer includes at least one of the following film layers: a titanium layer and a copper layer.

3. The method for manufacturing a semi-finished wafer according to claim 1, It is characterized in that The second metal layer includes at least one of the following film layers: a titanium layer and a copper layer.

4. A semi-finished wafer, It is characterized in that The semi-finished wafer is manufactured by the method for manufacturing the semi-finished wafer as described in any one of claims 1 to 3.

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