Anti-burn package structure, system in package module and package method

Abstract

This invention relates to a burn-out resistant packaging structure, a system-in-package module, and a packaging method, solving the problem of a short circuit in a power chip causing significant heat to spread to the motherboard and damage it. The burn-out resistant packaging structure is used for packaging a power chip package and a motherboard; it includes a self-protection structure and a soldering structure; the power chip package has a first pad on its lower surface; the self-protection structure includes an opening on its upper surface corresponding to the first pad, a through-hole extending from the opening to the lower surface of the self-protection structure, and a groove on the sidewall of the through-hole containing filler material; the soldering structure connects the first pad to a second pad on the upper surface of the motherboard through the through-hole and is in contact with the filler material, which absorbs the solder in the soldering structure in its molten state. This design enables timely disconnection of the power supply path between the motherboard and the power chip package when a short circuit occurs in the power chip, resulting in increased current and heat, thus protecting the motherboard from damage.

Description

Technical Field

[0001] This invention relates to the field of semiconductor packaging technology, and in particular to a burn-out-proof packaging structure, a system-level packaging module, and a packaging method. Background Technology

[0002] Traditional power chips mostly employ a discrete packaging structure, fixing the chip to a frame carrier board via a solder layer, thus creating interconnection and heat dissipation channels for the power chip. Embedded chip packaging technology is a more advanced packaging technology for power chips. By embedding the power chip and its components into a package, and through the design of reasonable heat conduction channels, it achieves high-efficiency heat dissipation for the power chip.

[0003] For embedded component packaging (ECP) technology, after the chip is buried, multiple film interfaces are involved. The film interfaces are prone to delamination, which can lead to moisture intrusion. This can cause short circuit faults when the chip is working, resulting in a sudden increase in current and a sharp increase in heat generation. The heat generated by the power chip cannot be dissipated in time, causing the power chip package to burn out. The heat then spreads to the motherboard (PCB) through the solder balls, causing damage to the motherboard.

[0004] Because motherboards are expensive to manufacture, they need to be protected to prevent damage when a power chip short-circuit and generates a lot of heat. Summary of the Invention

[0005] Based on the above analysis, the embodiments of the present invention aim to provide a burn-out-proof packaging structure, a system-in-package module, and a packaging method to solve the problem that when existing power chips experience short-circuit faults, a large amount of heat is generated and spreads to the motherboard, causing damage to the motherboard.

[0006] On one hand, embodiments of the present invention provide a burn-out resistant packaging structure for packaging power chip packages and motherboards; the packaging structure includes a self-protection structure and a soldering structure;

[0007] The power chip package includes a first pad located on its lower surface;

[0008] The self-protection structure includes an opening on its upper surface corresponding to the first pad, a through hole extending through the opening to the lower surface of the self-protection structure, and a groove on the sidewall of the through hole, wherein a filling material is disposed in the groove.

[0009] The welding structure is used to connect the first pad to the second pad on the upper surface of the motherboard through the through hole. The welding structure is in contact with the filler material, which is used to absorb the solder of the welding structure in the molten state.

[0010] Furthermore, the self-protection structure includes at least two self-protection layers, the opening is located in the self-protection layer that contacts the power chip package, and the groove is located in at least one of the remaining protective layers.

[0011] Furthermore, the welded structure includes an integrally formed base, neck, and welding ball;

[0012] The base is located in the opening and is in contact with the lower end of the first pad;

[0013] The neck is located in the through hole and is in contact with the filling material;

[0014] The solder ball is located on the lower surface of the self-protection structure and is in contact with the upper end of the second solder pad.

[0015] Furthermore, the effective adsorption volume of the filler material is greater than the volume of the neck solder.

[0016] Furthermore, the volume of the filling material is greater than or equal to two-thirds of the volume of the groove.

[0017] Furthermore, the filler material has a loose and porous structure, a melting point higher than that of the solder in the welded structure, and does not react with the solder.

[0018] Furthermore, the filling material includes at least one of porous carbon materials and porous metal materials.

[0019] In another aspect, embodiments of the present invention provide a burn-out resistant system-in-package module, including: a power chip package, a motherboard, and any of the above-mentioned burn-out resistant packaging structures. The burn-out resistant packaging structure is located between the power chip package and the motherboard, and connects a first pad on the lower surface of the power chip package and a second pad on the upper surface of the motherboard.

[0020] In another aspect, embodiments of the present invention provide a burn-out-proof packaging method for packaging a power chip package and a motherboard, wherein the lower surface of the power chip package is provided with a first pad, including:

[0021] A self-protective structure is formed, the self-protective structure including an opening on its upper surface, a through hole extending through the opening to the lower surface of the self-protective structure, and a groove on the sidewall of the through hole, wherein a filling material is disposed in the groove;

[0022] The self-protection structure is attached to the lower surface of the power chip package, and the opening is set to correspond to the first pad.

[0023] A welding structure is formed for connecting the first pad and the motherboard through the through hole. The welding structure is in contact with the filler material, which is used to absorb the solder of the welding structure in the molten state.

[0024] The motherboard is mounted to the lower end of the soldering structure, which contacts the second solder pad on the upper surface of the motherboard.

[0025] Furthermore, the formation of the self-protective structure includes:

[0026] At least two self-protective layers are etched to form openings and sub-vias;

[0027] At least two self-protective layers after etching are bonded together to form an opening on its upper surface, a through hole extending from the opening to the lower surface of the at least two self-protective layers, and a groove on the sidewall of the through hole.

[0028] A filling material is formed in the groove.

[0029] Compared with the prior art, the present invention can achieve at least the following beneficial effects:

[0030] By setting an anti-burn-out packaging structure between the power chip package and the motherboard, when the power chip short-circuits and the current and heat increase, the filling material in the groove of the anti-burn-out packaging structure absorbs the solder of the welding structure in the molten state, and cuts off the power supply path between the motherboard and the power chip package in time, so that the chip stops working and stops generating heat, thereby achieving the purpose of protecting the motherboard.

[0031] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0032] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0033] Figure 1 This is a schematic diagram of the structure of a burn-out-proof packaging structure for a power chip package and a motherboard according to an embodiment of this application;

[0034] Figures 2(a) to 2(f) This is a schematic diagram illustrating the fabrication of a burn-proof encapsulation structure according to one embodiment of this application.

[0035] Figure label:

[0036] 1-Main board; 11-Second solder pad; 2-Anti-burn-out package structure; 21-Soldering structure; 211 Base;

[0037] 212 - Neck; 213 - Weld ball; 22 - Self-protective structure; 221 - Self-protective layer; 2211 - Opening;

[0038] 2212 - Through-hole; 2213 - Groove; 2214 - Filler material; 3 - Power chip package; 31 - First pad Detailed Implementation

[0039] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0040] A specific embodiment of the present invention discloses a burn-out resistant packaging structure; please refer to [link / reference]. Figure 1 As shown. This burn-out protection packaging structure is used for packaging power chip packages and motherboards; the packaging structure includes a self-protection structure and a soldering structure; the power chip package includes a first pad located on its lower surface; the self-protection structure includes an opening located on its upper surface and corresponding to the first pad, a through hole extending through the opening to the lower surface of the self-protection structure, and a groove located on the sidewall of the through hole, the groove being filled with a filling material; the soldering structure is used to connect the first pad to a second pad on the upper surface of the motherboard through the through hole, the soldering structure being in contact with the filling material, the filling material being used to absorb the solder of the soldering structure in a molten state.

[0041] Compared with the prior art, the anti-burn-out packaging structure provided in this embodiment, by setting an anti-burn-out packaging structure between the power chip package and the motherboard, allows the filling material in the groove of the anti-burn-out packaging structure to absorb the molten solder of the welding structure when the power chip short-circuits and the current and heat increase. This timely cuts off the power supply path between the motherboard and the power chip package, causing the chip to stop working and stop generating heat, thereby achieving the purpose of protecting the motherboard.

[0042] For details, please see Figure 1 , Figures 2(a) to 2(f)The burn-proof packaging structure 2 is used for packaging the power chip package 3 and the motherboard 1. The burn-proof packaging structure 2 includes a self-protection structure 22 and a welding structure 21. The power chip package 3 includes a first pad 31 located on its lower surface. The self-protection structure 22 includes an opening 2211 located on its upper surface and corresponding to the first pad 31, a through hole 2212 extending from the opening 2211 to the lower surface of the self-protection structure, and a groove 2213 located on the sidewall of the through hole. A filling material 2214 is provided in the groove 2213. The welding structure 21 is used to connect the first pad 31 to the second pad 11 on the upper surface of the motherboard 1 through the through hole 2212. The welding structure 21 is in contact with the filling material 2214, and the filling material 2214 is used to absorb the solder of the welding structure 21 in the molten state.

[0043] Specifically, the power chip package is used to realize the electrical interconnection of the power chip and its associated components, while also protecting, dissipating heat, and enhancing the reliability of the packaged components. Optionally, the power chip package is an embedded package structure, such as an ECP package, which includes a power chip, capacitors, resistors, and interconnecting circuitry; through substrate embedding technology, the power chip is electrically interconnected with multiple capacitors, resistors, and surface inductors.

[0044] In one specific embodiment, the self-protection structure includes at least two self-protection layers, with an opening located in the self-protection layer that contacts the power chip package, and the groove located in at least one of the remaining protective layers.

[0045] For details, please see Figure 1 As shown in Figure 2(d), the self-protection structure 22 includes two self-protection layers 221. An opening 2211 is located in the upper self-protection layer 221, which contacts the power chip package 3. A groove 2213 is located in the lower self-protection layer, and the groove 2213 is filled with a filler material 2214. Further, when the self-protection structure includes three or more self-protection layers, the opening is located in the upper self-protection layer, which contacts the power chip package. The groove is located in at least one of the other protective layers besides the uppermost self-protection layer. Optionally, at least one groove is filled with a filler material. The horizontal dimensions of the opening and groove can be determined according to actual conditions, and this application does not limit this.

[0046] Please see Figures 2(a) to 2(c)Figure 2(a) is a cross-sectional view of a sub-opening and a sub-via formed by a single self-protective layer 221; Figure 2(b) is a cross-sectional view of an opening, a via, and a groove formed by two self-protective layers 221; and Figure 2(c) is a top view of Figure 2(b). The shapes of the openings and vias can be any combination of conventional shapes such as circles and polygons. The shape and size of the openings are determined by the shape of the first pad 31 on the lower surface of the power chip package 3. For example, if the first pad is circular with a diameter of 100 micrometers, then the shape of the opening is also circular, and the diameter is 100 micrometers plus assembly precision.

[0047] Optionally, the shape of the opening and the through hole can be the same or different; four examples are shown in Figure 2(c).

[0048] Optionally, the difference between the thickness of the opening and the thickness of the first pad is at least 10 micrometers. For example, if the thickness of the first pad is 20 micrometers, then the thickness of the opening is greater than or equal to 30 micrometers. This setting can increase the solder volume of the welding structure (base) located in the opening, thereby obtaining better current carrying capacity and electrical performance, and higher reliability. Of course, the welding structure can also only include the neck and solder ball, that is, the thickness of the first pad is equal to the thickness of the opening, as long as the electrical connection between the first pad and the welding structure can be guaranteed.

[0049] Optionally, the material of the self-protective layer can be glass or ceramic.

[0050] In a specific embodiment, please refer to FIG2(f), the welding structure 21 includes an integral base 211, a neck 212, and a solder ball 213; the base 211 is located in the opening 2211 and contacts the lower end of the first solder pad 31; the neck 212 is located in the through hole 2212 and contacts the filler material 2214; the solder ball 213 is located on the lower surface of the self-protection structure 22 and contacts the upper end of the second solder pad 11.

[0051] In one specific embodiment, the volume of the filler material is greater than or equal to two-thirds of the groove volume. The filler material is sufficient to absorb the solder in the molten state of the welded structure, causing the welded structure to break, thereby disconnecting the power supply path between the power chip package and the motherboard.

[0052] In one specific embodiment, the effective adsorption volume of the filler material is greater than the volume of the neck solder. The effective adsorption volume of the filler material is the maximum volume of solder that the filler material can absorb. This configuration ensures that the solder at the neck is completely adsorbed by the filler material, further guaranteeing the breakage of the weld structure.

[0053] In one specific embodiment, the filler material has a loose and porous structure, a melting point higher than that of the solder in the welded structure, and does not react with the solder.

[0054] For example, the solder material for the welded structure is Sn-Ag material with a melting point of 220℃; the filler material is porous carbon material with a melting point of 3500℃.

[0055] In one specific embodiment, the filling material includes at least one of porous carbon material and porous metal material.

[0056] Specifically, porous carbon materials include activated carbon, graphene, and other porous carbon materials that meet the requirements; porous metal materials have a large number of directional or random pores dispersed inside, such as porous materials of iron, nickel, copper, magnesium, and their alloys.

[0057] A specific embodiment of the present invention discloses a burn-out resistant system-in-package module; please refer to [link / reference]. Figure 1 The burn-out protection system-in-package module includes: a power chip package, a motherboard, and any one of the above-mentioned burn-out protection packaging structures. The burn-out protection packaging structure is located between the power chip package and the motherboard, and connects a first pad on the lower surface of the power chip package and a second pad on the upper surface of the motherboard.

[0058] The burn-out protection system-in-package module provided in this embodiment of the invention provides a burn-out protection packaging structure between the power chip package and the motherboard. When the power chip short-circuits and the current and heat increase, the filling material in the groove of the burn-out protection packaging structure absorbs the solder of the welding structure in a molten state, and cuts off the power supply path between the motherboard and the power chip package in time, so that the chip stops working and stops generating heat, thereby achieving the purpose of protecting the motherboard.

[0059] A specific embodiment of the present invention discloses a burn-proof packaging method, combined with Figure 1 , Figures 2(a) to 2(f) The following details the steps of the packaging method. This method is used to package a power chip package and a motherboard. The lower surface of the power chip package has a first pad. The method includes:

[0060] Step S10: Form a self-protective structure, the self-protective structure including an opening on its upper surface, a through hole extending from the opening to the lower surface of the self-protective structure, and a groove on the sidewall of the through hole, the groove being filled with a filling material;

[0061] Step S20: The self-protection structure is attached to the lower surface of the power chip package, and the opening is set to correspond to the first pad;

[0062] Step S30: Form a welding structure for connecting the first pad and the motherboard through the through hole. The welding structure is in contact with the filler material, which is used to absorb the solder of the welding structure in the molten state.

[0063] Step S40: Mount the motherboard to the lower end of the soldering structure, wherein the soldering structure contacts the second solder pad on the upper surface of the motherboard.

[0064] The anti-burn-out packaging method provided in this embodiment of the invention sets an anti-burn-out packaging structure between the power chip package and the motherboard. When the power chip short-circuits and the current and heat increase, the filling material in the groove of the anti-burn-out packaging structure absorbs the solder of the welding structure in a molten state, and cuts off the power supply path between the motherboard and the power chip package in time, so that the chip stops working and stops generating heat, thereby achieving the purpose of protecting the motherboard.

[0065] In one specific embodiment, please refer to Figures 2(a) to 2(d) The formation of a self-protective structure includes the following steps:

[0066] Step S11: Etch at least two self-protective layers to form opening 2211 and sub-vias, see Figure 2(a). Figure 2(a) only shows a cross-sectional view of one of the self-protective layers after etching. Cross-sectional views of the other self-protective layers after etching can also be seen in Figure 2(a).

[0067] Specifically, etching methods include laser etching, mechanical methods, and plasma etching.

[0068] Step S12: At least two self-protective layers after etching are bonded together to form an opening 2211 on its upper surface, a through hole 2212 extending through the opening to the lower surface of at least two self-protective layers, and a groove 2213 on the sidewall of the through hole, as shown in Figure 2(b). Figure 2(b) shows the structure after the two self-protective layers are bonded together.

[0069] Specifically, at least two self-protective layers can be bonded together using methods such as colloid bonding or electric field bonding.

[0070] Step S13: Form a filling material in the groove.

[0071] Specifically, based on Figure 2(b), the filler material is prepared into a gel form, and the gel-like filler material is injected into the structure of Figure 2(b) to form a shape. The solvent is removed by baking, and the excess filler material is removed by laser ablation or other chemical or physical methods, leaving only the filler material in the groove to form the structure shown in Figure 2(d).

[0072] In one specific embodiment, referring to Figure 2(e), the self-protective structure is mounted onto the lower surface of the power chip package, with the opening corresponding to the first pad, including:

[0073] Step S21: The self-protection structure is attached to the lower surface of the power chip package using adhesive, with the opening aligned with the first pad.

[0074] Optionally, the colloid can be a thermosetting adhesive.

[0075] In one specific embodiment, referring to Figure 2(f), solder balls are formed for connecting the first solder pad to the motherboard through through-holes. The solder structure is in contact with filler material, which is used to absorb the solder of the solder structure in the molten state, including:

[0076] Step S31: Fill the openings and through holes with solder and form solder balls by reflow.

[0077] Specifically, the base 211, neck 212, and solder balls 213 are formed into an integrated structure using stencil printing and reflow processes.

[0078] Furthermore, the motherboard is mounted to the lower end of the soldering structure, and the soldering structure contacts the second pad on the upper surface of the motherboard. That is, the motherboard with the second pad on its upper surface is attached to the structure shown in Figure 2(f), forming... Figure 1 The structure shown.

[0079] The above-described method embodiments and product structure embodiments are based on the same principle, and their related aspects can be referenced from each other, achieving the same technical effect.

[0080] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An anti-burnout package structure, characterized by, The application discloses a packaging structure for a power chip package and a mainboard; the packaging structure comprises a self-protection structure and a welding structure; The power chip package comprises a first pad on a lower surface thereof; The self-protection structure comprises an opening on an upper surface thereof, a through hole penetrating through the opening to a lower surface of the self-protection structure, and a groove on a side wall of the through hole, wherein a filling material is arranged in the groove; The welding structure is used for connecting the first pad and a second pad on an upper surface of the mainboard through the through hole, the welding structure is in contact with the filling material, the filling material is used for absorbing solder of the welding structure in a molten state, and a power supply path between the mainboard and the power chip package is cut off in time; The welding structure comprises a base, a neck and a solder ball in an integrated structure; The base is located in the opening and in contact with a lower end of the first pad; The neck is located in the through hole and in contact with the filling material; The solder ball is located on the lower surface of the self-protection structure and in contact with an upper end of the second pad; and an effective absorption volume of the filling material is greater than a volume of the neck solder.

2. The package structure of claim 1, wherein, The self-protection structure comprises at least two self-protection layers, the opening is located in a self-protection layer in contact with the power chip package, and the groove is located in at least one of the remaining self-protection layers.

3. The package structure of claim 1, wherein, The volume of the filling material is greater than or equal to two-thirds of a volume of the groove.

4. The package structure of claim 1, wherein, The filling material is a loose porous structure, has a melting point higher than that of solder of the welding structure, and does not react with the solder.

5. The package structure of claim 1, wherein, The filling material comprises at least one of a porous carbon material and a porous metal material.

6. A burn-in system-in-a-package module, comprising: The application further discloses a power chip package, a mainboard and a burnout-proof packaging structure according to any one of claims 1-5, wherein the burnout-proof packaging structure is located between the power chip package and the mainboard, and is connected with a first pad on a lower surface of the power chip package and a second pad on an upper surface of the mainboard. The application further discloses a burnout-proof packaging method for packaging a power chip package and a mainboard, wherein a lower surface of the power chip package is provided with a first pad; and the burnout-proof packaging method comprises the following steps:

7. A burn-in packaging method, characterized by, forming a self-protection structure, wherein the self-protection structure comprises an opening on an upper surface thereof, a through hole penetrating through the opening to a lower surface of the self-protection structure, and a groove on a side wall of the through hole, and a filling material is arranged in the groove; attaching the self-protection structure to the lower surface of the power chip package, wherein the opening is arranged in correspondence with the first pad; forming a welding structure, wherein the welding structure is used for connecting the first pad and the mainboard through the through hole, the welding structure is in contact with the filling material, the filling material is used for absorbing solder of the welding structure in a molten state, and a power supply path between the mainboard and the power chip package is cut off in time; attaching the mainboard to a lower end of the welding structure, wherein the welding structure is in contact with a second pad on an upper surface of the mainboard; the welding structure comprises a base, a neck and a solder ball in an integrated structure; the base is located in the opening and in contact with a lower end of the first pad; the neck is located in the through hole and in contact with the filling material; the solder ball is located on the lower surface of the self-protection structure and in contact with an upper end of the second pad; and an effective absorption volume of the filling material is greater than a volume of the neck solder. The solder ball is located at the lower surface of the self-protection structure and is in contact with the upper end of the second solder pad; and the effective adsorption volume of the filling material is greater than the volume of the neck solder.

8. The packaging method according to claim 7, characterized in that, The forming of the self-protection structure comprises: Respectively etching the at least two self-protection layers to form an opening and a sub-via hole; Bonding the etched at least two self-protection layers to form an opening on the upper surface, a via hole penetrating the opening to the lower surface of the at least two self-protection layers, and a groove on the side wall of the via hole; Forming a filling material in the groove.

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