WO2014153999A1

WO2014153999A1 - Package substrate unit and preparation method therefor, and substrate assembly

Info

Publication number: WO2014153999A1
Application number: PCT/CN2013/090740
Authority: WO
Inventors: 徐艺林; 高成志; 郑仰存; 谷新; 黄良松
Original assignee: 深南电路有限公司
Priority date: 2013-03-26
Filing date: 2013-12-27
Publication date: 2014-10-02
Also published as: CN104080280A; CN104080280B

Abstract

A method for preparing a package substrate unit comprises: preparing a multi-layer substrate, and designing more than one package substrate unit on the multi-layer substrate; treating a shielding groove on the periphery of each package substrate unit; metalizing a sidewall of the shielding groove; removing an outer copper foil of a central region of the package substrate unit; and on the central region with the outer copper foil removed, treating an accommodating groove used for fixing an electronic element. The embodiments of the present invention also provide a corresponding package substrate unit and a substrate assembly. In the technical solutions of the present invention, a shielding groove is treated on the periphery of a package substrate unit and a sidewall of the shielding groove is metalized as a metal shielding layer; in this manner, electromagnetic shielding is simply and reliably implemented on an electronic device and an additional shielding case is not required, which does not increase the thickness of a package substrate and does not decrease the universality of a product, the structure is reliable, the incapacitation risk is lowered, and the cost is low.

Description

Package substrate unit, manufacturing method thereof and substrate assembly

The present application claims priority to Chinese Patent Application No. 201310100854.2, entitled "A Package Substrate Unit and Its Manufacturing Method and Substrate Assembly", filed on March 26, 2013, the entire contents of which are hereby incorporated by reference. Combined in this application.

Technical field

The present invention relates to the field of circuit board processing technology, and in particular to a package substrate unit, a manufacturing method thereof and a substrate assembly.

Background technique

The conventional buried circuit board is usually formed by slotting a circuit board, embedding an electronic component such as a chip or the like in the opened slot, and fixing it. The electronic components buried in this type of circuit board are subject to external electromagnetic interference and cannot work optimally. In the prior art, a shield is added to the circuit board to avoid electromagnetic interference. However, the shield increases the thickness of the board and reduces the versatility of the product, which is not conducive to miniaturization, and the shield is not reliable enough, and there is a risk of failure such as displacement or shedding. Summary of the invention

Embodiments of the present invention provide a package substrate unit, a manufacturing method thereof, and a substrate assembly to solve the defects caused by electromagnetic shielding of a circuit board by using a shield cover in the prior art.

A first aspect of the present invention provides a method of fabricating a package substrate unit, comprising: fabricating a multi-layer substrate on which one or more package substrate units are planned; processing a shield trench at a periphery of each package substrate unit, The shielding slot includes a first shielding slot and a second shielding slot respectively processed from two sides of the multi-layer substrate, and the bottoms of the first shielding slot and the second shielding slot respectively reach the inner layer of the multi-layer substrate Two sides of the copper foil; metallizing the sidewall of the shielding groove; removing the outer copper foil of the central portion of the package substrate unit; processing the central portion for removing the outer copper foil for fixing the electronic component Hold the slot.

A second aspect of the present invention provides a package substrate unit, including: a central portion of the package substrate unit is provided with an inner layer copper foil and an outer layer for fixing the electronic component and the electronic component and the package substrate unit a shielding groove of the copper foil insulation, a shielding groove is formed in the periphery of the package substrate unit, and the shielding groove includes a first shielding groove and a second shielding groove respectively located on two sides of the multilayer substrate and corresponding to the position a shielding groove and a bottom of the second shielding groove respectively reach the inner layer copper of the multilayer substrate On both sides of the foil, a metallization layer for electromagnetically shielding the electronic component is processed on the sidewall of the shielding groove.

A second aspect of the present invention provides a substrate assembly, comprising: a package substrate unit as described above, an electronic component buried in a receiving groove formed by the package substrate unit, and respectively pressed on both sides of the package substrate unit The upper and lower substrates are electrically connected to the circuit patterns on the upper substrate or the lower substrate.

In the embodiment of the invention, the shielding groove is processed on the periphery of the package substrate unit, the sidewall of the shielding groove is metallized, and the electronic component is buried in the central region of the package substrate, and the outer copper foil on the surface of the package substrate unit and the side of the shielding groove are utilized. As a technical solution of the metal shielding layer, the wall can reliably electromagnetically shield the electronic components without adding a shielding cover, which does not increase the thickness of the packaging substrate, does not reduce the versatility of the product, and has a reliable structure and reduces the structure. The risk of failure and the cost of production are also lower.

DRAWINGS

1 is a flow chart of a method for fabricating a package substrate according to an embodiment of the present invention;

2 is a schematic view of an inner core plate of a processed inner layer pattern;

Figure 3 is a cross-sectional view of the inner core sheet of the processed inner layer pattern;

Figure 4 is a schematic view of a manufactured multilayer substrate;

Figure 5 is a schematic view of a package substrate unit having processed through holes;

6 is a schematic view of a package substrate unit in which a shielded groove has been processed;

Figure 7 is a cross-sectional view of a package substrate unit in which a shielded groove has been processed;

Figure 8 is a cross-sectional view of the package substrate unit after the shield trench is metallized;

Figure 9 is a cross-sectional view of a package substrate unit in which a dry film is provided;

Figure 10 is a cross-sectional view of a package substrate unit that has been etched;

Figure 11 is a cross-sectional view of the package substrate unit in which the receiving groove is processed;

Figure 12 is a schematic view of a separate package substrate unit;

Figure 13 is a schematic illustration of a substrate assembly including a package substrate unit.

detailed description

The embodiments of the present invention provide a method for fabricating a package substrate, which can solve the defects of the existing electromagnetic shielding technology for the circuit board. Embodiments of the present invention also provide corresponding package substrates. The details are described below separately. Embodiment 1

Referring to FIG. 1 , an embodiment of the present invention provides a method for fabricating a package substrate unit, including:

101. A multilayer substrate is fabricated, and one or more package substrate units are planned on the multilayer substrate. In this embodiment, the package substrate unit is designed in a multi-layer structure, and therefore, the processing of the package substrate unit starts from making a large multilayer substrate. A plurality of regularly arranged package substrate units are arranged on the larger multi-layer substrate, and the arrays are arranged in an array, horizontally and vertically.

The process of fabricating the multi-layer substrate comprises: processing the inner layer pattern on the inner layer copper foil 201 of the inner layer core board 200 as shown in FIGS. 2 and 3, the inner layer pattern may include a box-shaped line corresponding to the subsequent The shielding groove to be processed; as shown in FIG. 4, the outer layer 300 is pressed against the surface of the inner core plate, and the semi-cured layer 301 and the outer copper foil 302 are laminated on both sides.

In Fig. 2, the inner core plate 200 is exemplified by a single-sided copper clad plate. In practical applications, a double-sided copper clad plate can also be used. The line width of the above-mentioned square-shaped line corresponding to the shield groove is preferably 150 μm larger than the width of the shield groove to be processed later.

After the step, before the step of processing the shielding trench, the following steps may be further included: As shown in FIG. 5, the through hole 401 is processed at a top corner portion of each of the package substrate units 400 indicated by a broken line frame. The machined through holes 401 can be used later as via holes, alignment holes or tool holes between the layers. The method of machining the through hole 401 may be a mechanical drilling process.

102. The shielding slot is processed at a periphery of each of the package substrate units, and the shielding slot includes a first shielding slot and a second shielding slot respectively processed from two sides of the multi-layer substrate and corresponding to the position, the first shielding slot and The bottoms of the second shielding grooves respectively reach both sides of the inner layer copper foil of the multilayer substrate.

In this step, as shown in Fig. 6, at the periphery of the package substrate unit 400, the shield groove 402 is processed along the boundary indicated by the broken line frame. As shown in FIG. 7, the shielding groove 402 is separately processed from both sides of the package substrate unit during processing, and the first shielding groove 4021 is processed from the first surface, and the processing depth is to reach the inner layer copper foil 201. The first face processed from the second face is referred to as a second shield groove 4022 which is machined to a second face that reaches the inner layer copper foil 201.

In a specific application, four shielding grooves 402 may be respectively processed around the package substrate unit 400. Therefore, each of the package substrate units 400 has four shielding slots 402, and it should be noted that the four screens are Any one of the masks is composed of a first shielding groove and a second shielding groove respectively located on both sides of the package substrate unit.

In this embodiment, the step of processing the shielding groove at the periphery of each of the package substrate units may include: first, opening a window on the outer copper foil 302 of the shielding groove region to be processed around each of the package substrate units 400; The insulating medium under the opening window area is removed, and the inner layer copper foil 201 is exposed to form the shielding groove 402. Among them, the etching process can be used to open the window, and the C02 laser drilling machine can be used for laser ablation to remove the insulating dielectric layer.

After the grooving is completed, the respective package substrate units 202 are connected at the top corner and the like, and can be further processed as a whole to improve the processing efficiency. The layout method of planning a plurality of package substrate units on the substrate, and the arrangement of the respective units can improve the utilization rate of the substrate and reduce the production cost.

103. Metallize the sidewall of the shielding groove.

In this step, the sidewall of the shielding groove is metallized by a metallization process. If the through hole is previously machined, the through hole is also metallized at the same time. A cross-sectional view of a metallized package substrate unit is shown in Fig. 8. It can be seen that a metallization layer 403 is attached to the sidewall of the shield trench 402. The thickness of the metallization layer is preferably 15 μm or more. The metallized sidewalls are then used as a shield to provide metal shielding for the embedded electronic components within the package substrate unit. The metal layer formed on the side wall is plated with the outer copper foil on the surface of the substrate and the inner inner copper foil. The reliability is very good, and no detachment or displacement occurs during use.

In one embodiment, after the sidewall of the shielding trench is metallized, the shielding trench 402 may be filled by electroplating, or the shielding trench 402 may be filled with resin or ink.

104. Remove the outer layer copper foil in the central region of the package substrate unit.

In this step, a pattern transfer process is used to open a window in the central portion of the package substrate unit, that is, to remove the outer layer copper foil in the central portion. In order to subsequently process the receiving groove for embedding the electronic component in the central region. The steps of opening the window on the outer copper foil include:

As shown in FIG. 9, a dry film 405 is disposed on the package substrate unit 400 except for the central portion, so that the dry film 405 covers the shielding groove 402; and then, a chemical etching process is employed. The outer layer copper foil 302 of the central region is removed. After the etching is completed, the dry film is removed. As shown in Fig. 10, the insulating core layer 208 in the central region has been exposed. In an embodiment, after the step, the method further includes: plating the package substrate unit 400 with gold, and plating a layer of nickel gold or nickel palladium on the outer copper foil 302 that is not removed around the central region. Protects exposed copper and provides good solderability.

105. Processing a receiving groove for fixing the electronic component in a central region where the outer copper foil is removed.

As shown in Fig. 11, after the outer copper foil 302 in the central region is removed, the receiving groove 406 can be processed in the central region by a process such as mechanical milling or laser cutting. The receiving groove 406 penetrates the multilayer substrate up and down, and the sidewall thereof is an insulating material, which can be used for subsequent embedding of electronic components. In practical applications, in order to avoid short circuit caused by the subsequent embedded electronic component contacting the outer copper foil 302 around the central region, it may be slightly smaller than the size of the central region, that is, slightly smaller than the size of the window opening region on the outer copper foil 302. The processing receiving groove 406 is formed such that the edge of the receiving groove 406 has a certain size range, for example, no copper foil in the range of 0.5 mm, thereby achieving good insulation performance between the chip and the package substrate unit.

After the step, the following steps may be further included: cutting along a distance from the outer edge of the shielding slot 402 to cut the multilayer substrate into a plurality of independent package substrate units 400. A separate package substrate unit 400 after cutting, as shown in FIG.

Subsequently, the electronic component can be fixed in the receiving groove. Since the electronic component and the metallized sidewall are separated by the insulating substrate, the insulating property is very reliable, and the electronic component and the package substrate unit can be ensured. Each copper foil layer is completely insulated.

As shown in FIG. 13 , in the actual application, the upper and lower surfaces of the package substrate unit 400 in which the electronic component 501 is embedded may be respectively pressed onto the upper and lower substrates 502, and the upper and lower substrates 502 are respectively processed with circuit patterns, and the electronic components are respectively processed. The 501 can be electrically connected to the circuit pattern on the upper or lower substrate to constitute a practical substrate assembly.

In the above, the embodiment of the present invention provides a method for fabricating a package substrate, which uses a peripheral processing shield groove of the package substrate unit to metallize the sidewall of the shield trench, embeds an electronic component in a central region of the package substrate, and utilizes the package substrate. The outer layer of the surface of the copper foil on the surface of the unit and the side wall of the shielding groove serve as a technical solution for the metal shielding layer, and the single tube reliably realizes electromagnetic shielding of the electronic component without adding an additional shielding cover, which does not increase the thickness of the packaging substrate, and does not Reduce product versatility, and reliable structure, reducing the risk of failure. In addition, the method of the embodiment of the present invention only needs to use common equipment such as an image transfer device and an electroplating device, and does not need to add special equipment, and has good versatility. Embodiment 2

Referring to FIG. 12, an embodiment of the present invention provides a package substrate unit 400. The central portion of the package substrate unit 400 is provided with an inner layer for fixing the electronic component and the inner layer of the package substrate unit 400. a shielding groove 406 is formed on the periphery of the package substrate unit 400, and the shielding groove includes a first shielding groove and a corresponding position on both sides of the multilayer substrate. a shielding slot, the bottoms of the first shielding slot and the second shielding slot respectively reach two sides of the inner layer copper foil of the multilayer substrate, and the sidewall of the shielding slot is processed for electromagnetically conducting the electronic component Shielded metallization layer 403.

In other embodiments, the top corner portion of the package substrate unit 400 may be processed with a metalized via 401. The outer copper foil of the sealing substrate unit 400 may be plated with a layer of nickel gold or nickel palladium gold.

Referring to FIG. 13 , an embodiment of the present invention further provides a substrate assembly, including: the package substrate unit 400 as described above, the electronic component 501 embedded in the receiving groove 406 of the package substrate unit 400, and the respective voltages The upper and lower substrates 502 are bonded to both sides of the package substrate unit 400, and the electronic component 501 is electrically connected to a circuit pattern on the upper substrate or the lower substrate.

In the above, the embodiment of the present invention provides a package substrate unit and a substrate assembly including the package substrate unit, wherein sidewalls of the shielding groove around the package substrate unit are metallized, and electrons can be buried in a central region of the package substrate The component is electromagnetically shielded. The structure of the product is reliable, does not increase the thickness of the package substrate, does not reduce the versatility of the product, and has a low risk of failure. In addition, the package substrate unit of the embodiment of the present invention only needs to use common equipment such as an image transfer device and an electroplating device during processing, and does not need to add special equipment, and has good versatility.

The package substrate and the method for fabricating the same are provided in detail in the above description, but the description of the above embodiments is only for helping to understand the method and the core idea of the present invention, and should not be construed as limiting the present invention. Those skilled in the art will be able to devise variations or substitutions that are conceivable within the scope of the present invention.

Claims

Rights request

1. A method for manufacturing a package substrate unit, characterized by including:

Make a multi-layer substrate, and plan more than one packaging substrate unit on the multi-layer substrate; process shielding grooves around each packaging substrate unit, and the shielding grooves include corresponding holes processed from both sides of the multi-layer substrate. A first shielding groove and a second shielding groove, the bottoms of which respectively reach both sides of the inner copper foil of the multi-layer substrate;

Metalizing the side walls of the shielding trench;

Remove the outer copper foil from the central area of the package substrate unit;

A receiving groove for fixing electronic components is processed in the central area where the outer layer of copper foil is removed.

2. The method according to claim 1, characterized in that the manufacturing of the multi-layer substrate includes: processing an inner layer pattern on the inner copper foil of the inner core board;

The semi-cured layer and the outer copper foil are pressed onto the surface of the inner core board.

3. The method according to claim 1, characterized in that before processing a shielding groove around each packaging substrate unit, the method further includes:

Through holes are processed at the top corners of each package substrate unit.

4. The method according to claim 1, characterized in that processing a shielding groove around each packaging substrate unit includes:

A window is opened on the outer copper foil in the shielding groove area to be processed around each package substrate unit; the insulating medium under the windowed area is removed to expose the inner copper foil to form a shielding groove.

5. The method according to claim 1, characterized in that, after metallizing the side walls of the shielding trench, the method further includes:

The shielding groove is filled with electroplating, or the shielding groove is filled with resin or ink.

6. The method according to claim 1, characterized in that: removing the outer copper foil in the central area of the packaging substrate unit includes:

A layer of dry film is provided on other parts of the packaging substrate unit except the central area, so that the dry film covers the shielding groove;

A chemical etching process is used to remove the outer copper foil in the central area.

7. The method according to claim 1, characterized in that: the packaging substrate unit After removing the outer copper foil in the central area, it also includes:

The package substrate unit is plated with gold, so that the outer copper foil outside the central area that has not been removed is plated with a layer of nickel gold or nickel-palladium gold.

8. The method according to claim 1, characterized in that, processing a receiving groove for fixing electronic components in the central area where the outer layer of copper foil is removed includes:

The receiving groove is processed to a size slightly smaller than the central area, so that there is no outer copper foil within a certain size range of the edge of the receiving groove.

9. A packaging substrate unit with a multi-layer structure, characterized in that: a central area of the packaging substrate unit is provided for fixing electronic components, and connecting the electronic components with the inner layer of copper and foil on the packaging substrate unit and a receiving groove with outer copper and foil insulation. A shielding groove is processed around the package substrate unit. The shielding groove includes a first shielding groove and a second shielding groove respectively located on both sides of the multi-layer substrate and in corresponding positions. , the bottoms of the first shielding groove and the second shielding groove respectively reach both sides of the inner copper foil of the multi-layer substrate, and the side walls of the shielding groove are processed with metal for electromagnetic shielding of the electronic components. layer.

10. A substrate assembly, characterized by comprising: the packaging substrate unit as claimed in claim 9, electronic components embedded in the receiving grooves provided in the packaging substrate unit, and electronic components respectively pressed in the packaging substrate unit There are upper and lower substrates on both sides, and the electronic components are electrically connected to the circuit patterns on the upper substrate or the lower substrate.