Premolded substrate and method for manufacturing premolded substrate

Abstract

According to one aspect, a premolded substrate is provided that includes an electrically conductive base member having a first premolded groove formed on its lower surface and a second premolded groove formed on its upper surface to form a circuit pattern, a first premolded resin disposed in the first premolded groove, and a second premolded resin disposed in the second premolded groove.

Description

[Technical field]

[0001] The present invention relates to a premolded substrate. [Background technology]

[0002] 2. Description of the Related Art As electronic products continue to become smaller, lighter, faster, and have higher capacity, the technologies relating to substrates and lead frames used in the electronic products are rapidly developing.

[0003] Among the substrates or lead frames are premolded substrates or premolded lead frames in which a portion of mold resin is disposed. The premolded substrates or premolded lead frames have the advantage of shortening the semiconductor package manufacturing process because a portion of the mold resin is disposed in advance before the semiconductor chip is mounted.

[0004] Korean Patent Publication No. 10-2016-0021304 discloses a method for manufacturing a lead frame having a pre-molding resin disposed on the underside. Summary of the Invention [Problem to be solved by the invention]

[0005] SUMMARY OF THE PRESENT EMBODIMENT According to one aspect of the present invention, it is a primary object to provide an improved premolded substrate and a method for manufacturing the premolded substrate. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided a premolded substrate including an electrically conductive base member having a first premolded groove formed on a lower surface and a second premolded groove formed on an upper surface thereof, forming a circuit pattern, a first premolded resin disposed in the first premolded groove, and a second premolded resin disposed in the second premolded groove.

[0007] According to another aspect of the present invention, there is provided a method for manufacturing a premolded substrate, the method including the steps of: preparing an electrically conductive base member; processing a lower surface of the base member to form a first premolded groove; disposing a first premolded resin in the first premolded groove; processing an upper surface of the base member to form a second premolded groove; and disposing a second premolded resin in the second premolded groove. Effect of the Invention

[0008] According to one aspect of the present invention, the first premolded resin and the second premolded resin are disposed on the lower surface side and the upper surface side of the base member, respectively, so that there is an effect that warping of the premolded substrate is prevented. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a cross-sectional view of a premolded substrate according to one embodiment of the present invention. [Diagram 2] 2A to 2C are schematic cross-sectional views sequentially illustrating a process for manufacturing a premolded substrate according to an embodiment of the present invention. [Diagram 3] 2A to 2C are schematic cross-sectional views sequentially illustrating a process for manufacturing a premolded substrate according to an embodiment of the present invention. [Figure 4] 2A to 2C are schematic cross-sectional views sequentially illustrating a process for manufacturing a premolded substrate according to an embodiment of the present invention. [Diagram 5] 2A to 2C are schematic cross-sectional views sequentially illustrating a process for manufacturing a premolded substrate according to an embodiment of the present invention. [Figure 6] 2A to 2C are schematic cross-sectional views sequentially illustrating a process for manufacturing a premolded substrate according to an embodiment of the present invention. [Figure 7] 2A to 2C are schematic cross-sectional views sequentially illustrating a process for manufacturing a premolded substrate according to an embodiment of the present invention. [Figure 8] 2A to 2C are schematic cross-sectional views sequentially illustrating a process for manufacturing a premolded substrate according to an embodiment of the present invention. [Figure 9] 1 is a schematic cross-sectional view illustrating a semiconductor package to which a premolded substrate according to an embodiment of the present invention is applied; [Figure 10] 1 is a schematic flow chart illustrating a process for manufacturing a premolded substrate in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] According to one aspect of the present invention, there is provided a premolded substrate including an electrically conductive base member having a first premolded groove formed on a lower surface and a second premolded groove formed on an upper surface thereof, forming a circuit pattern, a first premolded resin disposed in the first premolded groove, and a second premolded resin disposed in the second premolded groove.

[0011] Here, the first pre-molded resin and the second pre-molded resin may be made of the same type of resin.

[0012] Here, cream solder may be applied to at least a portion of the exposed portion of the base member that is not covered by the first pre-molded resin and the second pre-molded resin.

[0013] According to another aspect of the present invention, there is provided a method for manufacturing a premolded substrate, the method including the steps of: preparing an electrically conductive base member; processing a lower surface of the base member to form a first premolded groove; disposing a first premolded resin in the first premolded groove; processing an upper surface of the base member to form a second premolded groove; and disposing a second premolded resin in the second premolded groove.

[0014] Here, the first pre-molded resin and the second pre-molded resin may be made of the same type of resin.

[0015] Here, the step of processing the lower surface of the base member to form the first pre-molded groove may be performed by using etching.

[0016] Here, the etching can also be performed by placing a dry film resist made of a photosensitive material on the lower surface of the base member and forming a resist pattern with the dry film resist.

[0017] Here, the step of processing the upper surface of the base member to form the second pre-molded groove may be performed by using etching.

[0018] Here, the etching is performed by etching a dry film resist made of a photosensitive material onto the base member. above Alternatively, a resist pattern may be formed using the dry film resist.

[0019] Here, the method may further include applying cream solder to at least a portion of the exposed portion of the base member that is not covered by the first premolding resin and the second premolding resin.

[0020] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings according to preferred embodiments. In addition, in this specification and drawings, components having substantially the same configurations are designated by the same reference numerals to avoid redundant description, and the drawings may include exaggerated parts in terms of size, length ratio, etc. to facilitate understanding.

[0021] The present invention will become clearer with reference to the following detailed description of the embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be embodied in various different forms. The present embodiments are provided solely for the purpose of making the disclosure of the present invention complete and fully conveying the scope of the invention to those skilled in the art to which the present invention pertains, and the present invention is defined only by the scope of the claims.

[0022] In addition, the terms used in this specification are for the purpose of describing the embodiments and do not limit the present invention. In this specification, the singular form includes the plural form unless otherwise specified in the text. The terms "comprise" and / or "comprising" used in this specification do not exclude the presence or addition of one or more other components, steps, operations, and / or elements of the referenced components, steps, operations, and / or elements. In this specification, terms such as top, bottom, upper, lower, left, right, first, and second may be used to describe various components, but the components are not limited by the terms. In other words, the terms do not indicate absolute directions or positions by themselves, but are used only to distinguish one component from another component.

[0023] FIG. 1 is a cross-sectional view of a premolded substrate according to one embodiment of the present invention.

[0024] As shown in FIG. 1, a premolded substrate 100 according to an embodiment of the present invention includes a base member 110, a first premolded resin 120, and a second premolded resin .

[0025] The base member 110 forms a part of the premolded substrate 100, and after processing, forms a circuit pattern.

[0026] The base member 110 is not particularly limited as long as it is made of an electrically conductive material. Examples of the material of the base member 110 include a single material such as Cu or Fe, copper alloys such as Cu·Sn, Cu·Zr, Cu·Fe, and Cu·Zn, and iron alloys such as Fe·Ni and Fe·Ni·Co. Commercially available lead frame materials can also be used as the material of the base member 110.

[0027] A first pre-molded groove 111 is formed in the lower surface of the base member 110, and a second pre-molded groove 112 is formed in the upper surface of the base member 110.

[0028] Among the portions of the base member 110, there are portions S1 and S2 that are exposed and not covered by the first pre-molded resin 120 and the second pre-molded resin 130, and the exposed portions S1 and S2 function as terminals for electrical connection to a semiconductor chip or an external circuit board.

[0029] The first premolded resin 120 is disposed in the first premolded groove 111 .

[0030] The first premolded resin 120 forms the premolded substrate 100 together with the base member 110 , but protects the base member 110 .

[0031] The first premolded resin 120 is an electrically insulating resin. The first premolded resin 120 may be a thermoplastic resin or a thermosetting resin, and preferably contains 80 to 90% or more of silica in order to minimize thermal expansion. The first premolded resin 120 may be filled using a liquid resin material or a solid tape containing a resin component.

[0032] Additionally, the first pre-molded resin 120 is made of a suitable material for preventing the cream solder applied to the exposed portions S1 and S2 of the base member 110 from spreading, but the present invention is not necessarily limited thereto.

[0033] The second pre-molded resin 130 is disposed in the second pre-molded groove 112 .

[0034] The second pre-molded resin 130 is an electrically insulating resin. The second pre-molded resin 130 may be a thermoplastic resin or a thermosetting resin, and preferably contains 80 to 90% or more of silica in order to minimize thermal expansion. The second pre-molded resin 130 may be filled using a liquid resin material or a solid tape containing a resin component.

[0035] Additionally, the second pre-molded resin 130 is made of a suitable material for preventing the cream solder applied to the exposed portions S1 and S2 of the base member 110 from spreading, but the present invention is not necessarily limited thereto.

[0036] According to this embodiment, the first premold resin 120 and the second premold resin 130 are made of the same type of resin. As a result, the resins disposed on both sides of the base member 110 are made of the same type, and no difference in thermal expansion coefficient occurs between the two sides of the premold substrate 100, so that warping of the premold substrate 100 can be more effectively prevented.

[0037] According to the present embodiment, the first premolded resin 120 and the second premolded resin 130 are made of the same type of resin, but the present invention is not limited thereto. That is, according to the present invention, the first premolded resin 120 and the second premolded resin 130 may be made of different types of resin.

[0038] Hereinafter, a method for manufacturing the premolded substrate 100 according to the present embodiment will be described with reference to FIGS.

[0039] 2 to 8 are schematic cross-sectional views sequentially illustrating a process for manufacturing a premolded substrate according to an embodiment of the present invention, FIG. 9 is a schematic cross-sectional view illustrating a semiconductor package to which a premolded substrate according to an embodiment of the present invention is applied, and FIG. 10 is a schematic flowchart illustrating a process for manufacturing a premolded substrate according to an embodiment of the present invention.

[0040] First, as shown in Fig. 2, a base member 110 is prepared (Step S1). The base member 110 is made of an electrically conductive material and includes a lower surface 110a and an upper surface 110b.

[0041] Next, the lower surface 110a of the base member 100 is processed to form a first pre-molded groove 111 as shown in FIG. 3 (Step S2).

[0042] Here, an etching method can be used as a method for processing the lower surface 110a of the base member 100. The etching method can be wet etching, dry etching, or the like. Specifically, the etching method is to provide a dry film resist made of a photosensitive material on the lower surface 110a of the base member 100, expose and develop the dry film resist, and form a resist pattern with the dry film resist. Then, the formed resist pattern can be used to perform etching to form the first pre-mold groove 111. Next, a first pre-molded resin 120 is applied and placed in the first pre-molded groove 111 (step S3).

[0043] 4, the first premolded resin 120 is formed to have not only a portion 120a located in the first premolded groove 111 but also a portion 120b covering a part of the lower surface 110a. In this case, the lower surface 110a of the base member 100 can be exposed by a brushing process, a polishing process, an etching process, or the like to form an exposed portion S1 as shown in FIG.

[0044] Next, the upper surface 110b of the base member 110 is processed to form a second pre-molded groove 112 (step S4).

[0045] Here, an etching method can be used to process the upper surface 110b of the base member 100. The etching method can be wet etching, dry etching, or the like.

[0046] An example of a method for processing the upper surface 110b of the base member 100 will be specifically described as follows. First, a dry film resist made of a photosensitive material is placed on the upper surface 110b of the base member 100, and the dry film resist is exposed and developed to form a resist pattern R with the dry film resist as shown in Fig. 5. Next, the formed resist pattern R is used to perform etching to form a second pre-mold groove 112 as shown in Fig. 6.

[0047] Next, the second pre-molded resin 130 is applied and disposed in the second pre-molded groove 112 (step S5).

[0048] 7, the second premolded resin 130 is formed to have not only a portion 130a located in the second premolded groove 112 but also a portion 130b covering a part of the upper surface 110b. In this case, the upper surface 110b of the base member 100 can be exposed by a brushing process, a polishing process, an etching process, or the like to form an exposed portion S2 as shown in FIG.

[0049] The exposed portions S1 and S2 of the base member 110 that are not covered by the first pre-molded resin 120 and the second pre-molded resin 130 function as terminals for electrical connection to a semiconductor chip or an external circuit board. Therefore, further processes can be performed on the exposed portions S1 and S2. For example, at least a portion of the exposed portions S1 and S2 can be plated with Au, Pd, or coated with an organic solderbility preservative (OSP) to increase solder adhesion in a subsequent process.

[0050] Meanwhile, in the manufacturing of the premolded substrate 100, the manufacturing of the premolded substrate 100 may be completed with the structure shown in Fig. 1, and the manufactured premolded substrate 100 may be transferred to a semiconductor package manufacturing process, and the semiconductor package manufacturing process may proceed, but the present invention is not limited thereto. That is, according to the present invention, in the manufacturing process of the premolded substrate 100, a process of disposing cream solder K on at least a part of the exposed portions S1 and S2 of the base member 110 shown in Fig. 1, as shown in Fig. 8, may be added. That is, the process of disposing cream solder K is generally performed in the semiconductor packaging process, but as described above, since the exposed portions S1 and S2 of the base member 110 perform the function of terminals for electrical connection, the cream solder K may be disposed in advance on at least a part of the exposed portions S1 and S2 in the manufacturing process of the premolded substrate 100. In this case, even if the shape of the cream solder K is fluid, it will not overflow from the exposed portions S1, S2. This is because the materials of the base member 110, the first premolded resin 120, and the second premolded resin 130 are different, and due to the material properties, the surfaces of the first premolded resin 120 and the second premolded resin 130 push out the cream solder K, thereby preventing the cream solder K from spreading.

[0051] After the cream solder K is applied, the cream solder K is used in the semiconductor package manufacturing process to electrically connect the electrodes P of the semiconductor chip C to the base member 110. Next, encapsulation is performed using a molding resin G such as an epoxy material or a urethane material, thereby realizing the structure of the semiconductor package 200 as shown in FIG.

[0052] According to this embodiment, the cream solder K is directly used to electrically connect the electrodes P of the semiconductor chip C to the base member 110, but the present invention is not limited thereto. That is, according to the present invention, the cream solder K can also be used to form bumps to electrically connect the chip C.

[0053] The manufacturing process of the premolded substrate 100 according to the present embodiment described above is carried out in the order of forming the first premolded groove 111 and disposing the first premolded resin 120, forming the second premolded groove 112, and disposing the second premolded resin 130, but the present invention is not limited thereto. That is, the manufacturing process of the premolded substrate according to the present invention may also be carried out in the order of forming the second premolded groove 112 and disposing the second premolded resin 130, forming the first premolded groove 111, and disposing the first premolded resin 120. Also, the manufacturing process of the premolded substrate according to the present invention may be carried out in the order of first forming the first premolded groove and the second premolded groove, and then disposing the first premolded resin and the second premolded resin.

[0054] The above-described process for the premolded substrate 100 is performed in units of a flat plate, but the present invention is not limited thereto. That is, according to the present invention, the above-described process for the premolded substrate 100 may be performed continuously in a roll-to-roll process.

[0055] As described above, in the premolded substrate 100 according to the present embodiment, the first premolded groove 111 is formed on the lower surface 110a of the base member 110, the second premolded groove 112 is formed on the upper surface 110b, the first premolded resin 120 is disposed in the first premolded groove 111, and the second premolded resin 130 is disposed in the second premolded groove 112, so that the premolded resin is disposed on both the lower surface side and the upper surface side of the base member 110. With such a structure, when looking at the overall structure of the premolded substrate 100, the difference in thermal expansion coefficient between the lower surface side and the upper surface side becomes small, which makes it possible to prevent the substrate from warping. In particular, according to the present embodiment, the first premolded resin 120 and the second premolded resin 130 are made of the same type of resin, so that the substrate can be more effectively prevented from warping.

[0056] In addition, according to this embodiment, when cream solder K is applied to the exposed portions S1, S2 of the base member 110 in the manufacturing process of the premolded substrate 100 or the semiconductor package 200, the materials of the base member 110, the first premolded resin 120, and the second premolded resin 130 are different, so that the spreading phenomenon of the cream solder K is naturally prevented, and the quality of the semiconductor package can be improved.

[0057] Although one aspect of the present invention has been described with reference to the embodiments illustrated in the accompanying drawings, these are merely illustrative, and those skilled in the art will recognize that various modifications and equivalent embodiments are possible therefrom. Therefore, the true scope of protection of the present invention is defined only by the claims. [Industrial Applicability]

[0058] The premolded substrate and the method for manufacturing the premolded substrate according to the present embodiment are also applicable to industries that manufacture premolded substrates.

Claims

1. Providing an electrically conductive base member; machining a lower surface of the base member to form a first pre-molded groove; disposing a first pre-molded resin in the formed first pre-molded groove; processing the first premolded resin so that a lower surface of the first premolded resin is flush with a lower surface of the base member; machining an upper surface of the base member to form a second pre-molded groove; disposing a second pre-molded resin in the formed second pre-molded groove; and processing the second premolded resin so that an upper surface of the second premolded resin and an upper surface of the base member are flush with each other.

2. The method for manufacturing a premolded substrate according to claim 1 , wherein the first premolded resin and the second premolded resin are made of the same type of resin.

3. The method of claim 1 , wherein the step of processing the lower surface of the base member to form the first pre-molded groove is performed using etching.

4. 4. The method of claim 3, wherein the etching is performed by applying a dry film resist made of a photosensitive material to the lower surface of the base member and forming a resist pattern with the dry film resist.

5. The method of claim 1 , wherein the processing of the top surface of the base member to form the second pre-molded groove is performed using etching.

6. 6. The method of claim 5, wherein the etching is performed by disposing a dry film resist made of a photosensitive material on the upper surface of the base member and forming a resist pattern with the dry film resist.

7. 2. The method for manufacturing a premolded substrate according to claim 1, further comprising the step of applying cream solder to at least a portion of the exposed portion of the base member that is not covered by the first premolded resin and the second premolded resin.

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