Encapsulation laminate structure and its preparation method

Abstract

The present disclosure provides an encapsulation laminate structure and a method for manufacturing the same. The method for manufacturing the encapsulation laminate structure includes the following steps: providing a first encapsulation member and a second encapsulation member, the first encapsulation member including connection pads, and the second encapsulation member including connection members; preparing a pattern layer on the first encapsulation member to expose the connection pads; welding the connection members on the second encapsulation body to the connection pads; removing the pattern layer; and filling a support layer covering the connection members between the first encapsulation member and the second encapsulation member. The method for manufacturing the encapsulation laminate structure prepares a removable pattern layer to reserve sufficient operating space, which can not only effectively reduce the difficulty of subsequent preparation of the support layer, but also facilitate the discharge of gas between the first encapsulation member and the second encapsulation member when preparing the support layer, and can effectively improve or avoid the void problem caused by re-filling.

Description

Technical Field

[0001] The present disclosure relates to the field of packaging technologies, and particularly to a packaging stack structure and a preparation method thereof. Background Art

[0002] A Package-on-Package (POP) structure refers to integrating two semiconductor device packages in a stacked manner to meet the requirements of miniaturization and high integration of semiconductor devices. During the preparation process of the packaging stack structure, it is usually necessary to weld two packages containing semiconductor devices together. In traditional technologies, a layer of molding material needs to be prepared through a special-shaped mold to assist the alignment and connection of the two packages, which results in complex preparation processes and is likely to reduce the product reliability. Summary of the Invention

[0003] Based on this, in order to improve the preparation process and enhance the reliability of the packaging stack structure, it is necessary to provide a preparation method for the packaging stack structure.

[0004] According to some embodiments of the present disclosure, a preparation method for a packaging stack structure is provided, which includes the following steps:

[0005] Provide a first package and a second package, wherein the first package includes connection pads, and the second package includes connecting members;

[0006] Prepare a pattern layer on the first package to expose the connection pads;

[0007] Weld the connecting members on the second package to the connection pads;

[0008] Remove the pattern layer;

[0009] Fill a support layer covering the connecting members between the first package and the second package.

[0010] In some embodiments of the present disclosure, the first package further includes a first package body, the connection pads are disposed on the surface of the first package body, the second package further includes a second package body, the connecting members are disposed on the surface of the second package body and protrude from the second package body, and the support layer contacts the first package body and the second package body.

[0011] In some embodiments of the present disclosure, the first package body includes an interposer base layer and a first encapsulation layer, the first encapsulation layer surrounds the interposer base layer, and the connection pads are disposed on the interposer base layer; the support layer is prepared on the interposer base layer and the first encapsulation layer.

[0012] In some embodiments of the present disclosure, the step of forming the pattern layer includes:

[0013] Preparing a pattern material layer covering the connection pads on the first encapsulation;

[0014] Etching the pattern material layer to obtain an opening exposing the connection pads, thereby forming the pattern layer.

[0015] In some embodiments of the present disclosure, after preparing the pattern material layer, it further includes:

[0016] Performing a doping treatment on the pattern material layer, and the doping elements used in the doping treatment include one or more of boron element and phosphorus element.

[0017] In some embodiments of the present disclosure, there are multiple connection pads, and the multiple connection pads are arranged in an array. The distance between the outermost connection pad and the inner wall of the opening of the pattern material layer is more than half of the distance between adjacent connection pads.

[0018] In some embodiments of the present disclosure, the material of the support layer is different from the material of the pattern layer.

[0019] In some embodiments of the present disclosure, the preparation step of the support layer includes:

[0020] Filling a support material layer into the gap between the first encapsulation and the second encapsulation, and the support material layer covers the connecting member;

[0021] Performing a curing treatment on the support material layer to form the support layer.

[0022] In some embodiments of the present disclosure, the pattern layer includes silicon oxide, silicon nitride, silicon oxynitride or photoresist; and / or,

[0023] The support layer includes a plastic encapsulation material.

[0024] In some embodiments of the present disclosure, the pattern layer includes photoresist, and the step of removing the pattern layer includes: dissolving the pattern layer with a photoresist remover.

[0025] In some embodiments of the present disclosure, the coefficient of thermal expansion of the support layer is between the coefficient of thermal expansion of the first encapsulation and the coefficient of thermal expansion of the second encapsulation.

[0026] Furthermore, according to still some other embodiments of the present disclosure, there is also provided a stacked encapsulation structure, which includes:

[0027] A first encapsulation, and the first encapsulation includes connection pads;

[0028] A second encapsulation member, the second encapsulation member including a connecting member soldered to the connection pad;

[0029] A support layer filled between the first encapsulation member and the second encapsulation member, and the support layer covering the connecting member.

[0030] In some embodiments of the present disclosure, the first encapsulation member further includes a first encapsulation main body, the connection pad is disposed on the surface of the first encapsulation main body, the second encapsulation member further includes a second encapsulation main body, the connecting member is disposed on the surface of the second encapsulation main body and protrudes from the second encapsulation main body, and the support layer contacts the first encapsulation main body and the second encapsulation main body.

[0031] In some embodiments of the present disclosure, the first encapsulation member includes a first plastic encapsulation layer and an interposer base layer, the first plastic encapsulation layer surrounds the interposer base layer, and the support layer is disposed on the first plastic encapsulation layer and the interposer base layer.

[0032] In some embodiments of the present disclosure, the support layer includes a support base material and a support filler, the first plastic encapsulation layer includes a first plastic encapsulation base material and a first plastic encapsulation filler, the support base material is the same as the first plastic encapsulation base material, and the particle size of the support filler is smaller than the particle size of the first plastic encapsulation filler.

[0033] In some embodiments of the present disclosure, the support layer includes a support base material and a support filler, the second encapsulation member includes a second plastic encapsulation layer, the second plastic encapsulation layer includes a second plastic encapsulation base material and a second plastic encapsulation filler, the support base material is the same as the second plastic encapsulation base material, and the particle size of the support filler is smaller than the particle size of the second plastic encapsulation filler.

[0034] In some embodiments of the present disclosure, the coefficient of thermal expansion of the support layer is between the coefficient of thermal expansion of the first encapsulation member and the coefficient of thermal expansion of the second encapsulation member.

[0035] In the traditional technology, a layer of molding material is usually prepared on the first encapsulation member to assist in connection. Limited by the actual preparation process, there is always a certain gap between the second encapsulation member and the molding material, which easily leads to poor encapsulation.

[0036] In the preparation method of the above-mentioned encapsulated laminate structure, a pattern layer is prepared on the first encapsulation member. The pattern layer has openings exposing the connection pads. The connecting member on the second encapsulation member can be connected to the first encapsulation member in alignment through the openings of the pattern layer. Then, the pattern layer is removed, and a support layer is filled between the first encapsulation member and the second encapsulation member. In this preparation method, the pattern layer is temporarily introduced to assist the alignment connection between the first encapsulation member and the second encapsulation member, and then the pattern layer is removed to leave sufficient space between the first encapsulation member and the second encapsulation member. Finally, the support layer is filled, which can completely enclose the space between the first encapsulation member and the second encapsulation member and improve the reliability of the encapsulation. At the same time, in this preparation method, the introduction of special-shaped molds can be avoided, thereby improving the complexity of the process and the process cost.

[0037] In the traditional technology, if the molding material is filled into the gap again to improve the reliability of the encapsulation, not only is the operation difficult, but also the problem of filling voids will occur, resulting in new encapsulation defects.

[0038] Compared with the traditional technology, the preparation method of the encapsulated laminate structure provided by the present disclosure prepares a removable pattern layer to reserve sufficient operation space, which can not only effectively reduce the difficulty of subsequent preparation of the support layer, but also facilitate the discharge of gas between the first encapsulation member and the second encapsulation member when preparing the support layer, and can effectively improve or avoid the void problem caused by re-filling.

[0039] The above description is only an overview of the technical solution of the present invention. In order to understand the technical means of the present invention more clearly and implement it according to the content of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0041] Figure 1 It is a schematic diagram of the steps of a preparation method of an encapsulated laminate structure;

[0042] Figure 2 Shows the structure of a first encapsulation member;

[0043] Figure 3 For Figure 2 The structure diagram of preparing a pattern material layer on the basis of the shown structure;

[0044] Figure 4 For Figure 3Schematic diagram of a pattern layer formed by etching on the basis of the shown structure;

[0045] Figure 5 shows Figure 4 a top view of the structure in;

[0046] Figure 6 For setting a second encapsulation member on the basis of the Figure 4 shown structure, schematic diagram of the structure;

[0047] Figure 7 For removing the pattern layer on the basis of the Figure 6 shown structure, schematic diagram of the structure;

[0048] Figure 8 For preparing a support layer on the basis of the Figure 7 shown structure, schematic diagram of the structure;

[0049] Wherein, the meanings of the respective reference numerals are as follows:

[0050] 110, connection pad; 120, intermediate base layer; 130, first plastic encapsulation layer; 140, first chip structure; 141, first adhesion layer; 142, first semiconductor chip; 143, second adhesion layer; 144, second semiconductor chip; 145, third adhesion layer; 146, encapsulation base; 150, pattern material layer; 151, pattern layer; 152, connection hole; 160, connecting member; 170, second encapsulation main body; 180, support layer. Detailed implementation manners

[0051] For facilitating the understanding of the present disclosure, the present disclosure will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present disclosure are given in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the disclosure of the present disclosure is more thorough and comprehensive.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this disclosure belongs. The terms used in the specification of this disclosure herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0053] It should be understood that when an element or layer is referred to as being "on", "adjacent to", "connected to" or "coupled to" another element or layer, it can be directly on, adjacent to, connected or coupled to the other element or layer, or there may be intervening elements or layers. The means of electrical connection is used to indicate that current can conduct between multiple electrically connected elements, and the specific means can be that one element directly contacts another element, or one element is connected to another element through other conductive elements. In contrast, when an element is referred to as being "directly on", "directly adjacent to", "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers. It should be understood that although terms such as first, second, third, etc. may be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Thus, without departing from the teachings of the present disclosure, the first element, component, region, layer or part discussed below may be referred to as the second element, component, region, layer or part.

[0054] Spatial relationship terms such as "under", "below", "lower", "beneath", "above", "upper", etc. are used herein for convenience in describing the relationship of one element or feature shown in the figures to other elements or features. It should be understood that, in addition to the orientation shown in the figures, spatial relationship terms are intended to include different orientations of the device in use and operation. For example, if the device in the figures is flipped, then an element or feature described as "under" or "beneath" or "below" another element will be oriented "on" the other element or feature. Thus, the exemplary terms "under" and "below" can include both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatial descriptors used herein are to be interpreted accordingly.

[0055] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present disclosure. As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, specify the presence of the stated features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups. As used herein, the term "and / or" includes any and all combinations of the related listed items.

[0056] The present disclosure provides a method for preparing an encapsulated stacked structure, which includes the following steps: providing a first encapsulation member and a second encapsulation member, the first encapsulation member including connection pads, and the second encapsulation member including connection members. Preparing a pattern layer on the first encapsulation member to expose the connection pads. Welding the connection members on the second encapsulation member to the connection pads exposed in the pattern layer. Removing the pattern layer, and then filling a support layer covering the connection members between the first encapsulation member and the second encapsulation member.

[0057] In the above method for preparing an encapsulated stacked structure, a pattern layer is prepared on the first encapsulation member, and the pattern layer has openings exposing the connection pads. The connection members on the second encapsulation member can be connected to the first encapsulation member in alignment through the openings of the pattern layer. Then, the pattern layer is removed, and a support layer is filled between the first encapsulation member and the second encapsulation member. In this preparation method, the pattern layer is temporarily introduced to assist the alignment connection between the first encapsulation member and the second encapsulation member, and then the pattern layer is removed to leave sufficient space between the first encapsulation member and the second encapsulation member. Finally, the support layer is filled, which can completely enclose the space between the first encapsulation member and the second encapsulation member and improve the reliability of the encapsulation.

[0058] In some traditional technologies, a layer of molding material is usually prepared on the first encapsulation member to assist in the connection. Limited by the actual preparation process, there will always be a certain gap between the second encapsulation member and the molding material, which is likely to cause poor encapsulation. If molding material is filled into the gap again to improve the reliability of the encapsulation, not only is the operation difficult, but also the problem of filling voids will occur, resulting in new poor encapsulation.

[0059] Compared with traditional technologies, the method for preparing an encapsulated stacked structure provided by the present disclosure prepares a removable pattern layer to reserve sufficient operation space, which can not only effectively reduce the difficulty of subsequent preparation of the support layer, but also facilitate the discharge of gas between the first encapsulation member and the second encapsulation member when preparing the support layer, and can effectively improve or avoid the void problem caused by re-filling.

[0060] In some examples of this embodiment, the pattern layer contacts the second encapsulation member to support the second encapsulation member and improve the stability when the second encapsulation member is connected to the first encapsulation member.

[0061] In some examples of this embodiment, the first encapsulation member further includes a first encapsulation main body, the connection pads are arranged on the surface of the first encapsulation main body, the second encapsulation member further includes a second encapsulation main body, the connection members are arranged on the surface of the second encapsulation main body and protrude from the second encapsulation main body, and the support layer contacts the first encapsulation main body and the second encapsulation main body.

[0062] In some examples of this embodiment, the first encapsulation main body includes an interposer base layer and a first molding layer, the first molding layer surrounds the interposer base layer, and the connection pads are arranged on the interposer base layer; the support layer is prepared on the interposer base layer and the first molding layer.

[0063] Among them, the first encapsulation body may include a first chip structure, and the second encapsulation body may include a second chip structure. The chips in the first chip structure and the chips in the second chip structure may be the same or different. In some examples of this embodiment, the chips in the first chip structure may be memory chips, and the chips in the second chip structure may be flash memory chips.

[0064] In some examples of this embodiment, the step of forming the pattern layer includes: preparing a pattern material layer covering the connection pads on the first encapsulation; and etching the pattern material layer to obtain openings exposing the connection pads to form the pattern layer. It can be understood that the material of the pattern layer can be a material that can withstand patterning treatment and can be removed subsequently. For example, the pattern material layer can be selected from materials that can be etched.

[0065] In some examples of this embodiment, the material of the pattern layer includes one or more of silicon oxide, silicon nitride, silicon oxynitride, and photoresist. Further, the material of the pattern layer may include photoresist. Photoresist has the advantages of lower operation difficulty and higher precision during patterning treatment. In addition, the photoresist after exposure treatment can still be easily removed by a suitable solvent, so it is suitable for the preparation method of the encapsulation stack structure of the present disclosure.

[0066] In some examples of this embodiment, after forming the pattern material layer, it further includes: doping the pattern material layer. Doping the pattern material layer can improve the strength of the prepared pattern layer and further improve the welding stability of the second encapsulation.

[0067] In some examples of this embodiment, when doping the pattern material layer, the doping elements may include one or more of boron element and phosphorus element to improve the strength of the pattern material layer.

[0068] In some examples of this embodiment, the connecting member may be a metal material. For example, the connecting member includes one or more of gold, copper, nickel, tin, and lead.

[0069] In some examples of this embodiment, there are multiple connection pads, and the multiple connection pads are arranged in an array. The distance between the outermost connection pad and the inner wall of the opening of the pattern layer is more than half of the distance between adjacent connection pads. Setting the distance between the connection pad and the inner wall of the opening of the pattern layer can improve or avoid damage caused by the connecting member on the second encapsulation touching the pattern layer.

[0070] In some examples of this embodiment, the material of the support layer is different from the material of the pattern layer. Among them, using a pattern layer with a material different from that of the support layer can remove the pattern layer without affecting the encapsulation materials in the first encapsulation and the second encapsulation as much as possible.

[0071] In some examples of this embodiment, the pattern layer can be removed by using a solvent capable of dissolving the pattern layer. For example, if the material of the pattern layer includes photoresist, the pattern layer can be removed by using a photoresist remover.

[0072] In some examples of this embodiment, the step of filling the support layer includes: filling a support material layer into the gap between the first package and the second package, and the support material layer covers the connecting member. The support material layer is cured to form a support layer.

[0073] In some examples of this embodiment, the material of the support layer includes a molding compound. Among them, the molding compound can include one or both of epoxy resin and silicone resin.

[0074] In some examples of this embodiment, the coefficient of thermal expansion of the support layer is between the coefficient of thermal expansion of the first package and the coefficient of thermal expansion of the second package. By setting the coefficient of thermal expansion of the support layer between the first package and the second package, the warping problem caused by the large difference in the coefficients of thermal expansion of the first package and the second package is improved, so that the combination between the first package, the second package and the support layer is more firm.

[0075] To facilitate the understanding of the preparation method of the package stack structure in the above embodiment, the present disclosure Figure 1 provides a schematic diagram of the steps of a preparation method of a package stack structure. Referring to Figure 1 as shown, the preparation method of the package stack structure includes steps S1 to S6, and the further description is as follows.

[0076] Step S1, provide a first package.

[0077] Figure 2 shows a structure of a first package including connection pads 110. Referring to Figure 1 as shown, the first package includes a first package body and connection pads 110 provided on the first package body. Among them, the first package body includes an interposer base layer 120 and a first molding layer 130. The first molding layer 130 surrounds the interposer base layer 120, and the connection pads 110 are provided on the interposer base layer 120.

[0078] In some examples of this embodiment, the connection pads 110 are flush with the interposer base layer 120.

[0079] Among them, the first molding layer 130 is used to encapsulate the outer wall of the interposer base layer 120. The material of the molding layer can include a molding compound, such as one or more of epoxy resin and silicone resin. The way to prepare the first molding layer 130 can be an injection molding process or a molded bottom fill process.

[0080] In some examples of this embodiment, the connection pad 110 is also flush with the first encapsulation layer 130.

[0081] Referring Figure 2 As shown, the first encapsulation body further includes a first chip structure 140 disposed on a surface of the interposer substrate layer 120 away from the connection pad 110. In the direction away from the interposer substrate layer 120, the first chip structure 140 includes a first adhesion layer 141, a first semiconductor chip 142, a second adhesion layer 143, a second semiconductor chip 144, a third adhesion layer 145, and an encapsulation substrate 146 that are sequentially stacked. The first adhesion layer 141 is connected to the lower surface of the interposer substrate layer 120. Electrical connections can be made between the first semiconductor chip 142 and the encapsulation substrate 146 and between the second semiconductor chip 144 and the encapsulation substrate 146 through wires.

[0082] Referring Figure 2 As shown, connection contacts are also disposed on the interposer substrate layer 120, and the connection contacts can be electrically connected to the encapsulation substrate 146 through wires.

[0083] Step S2, preparing a pattern material layer on the first encapsulation component.

[0084] Figure 3 shows a schematic structural diagram of preparing a pattern material layer 150 based on the Figure 2 shown structure. Among them, the pattern material layer 150 is prepared on the interposer substrate layer 120 and covers the connection pad 110. Further, the pattern material layer 150 also covers at least part of the first encapsulation layer 130.

[0085] Among them, the pattern material layer 150 may include an etchable material. For example, the pattern material layer 150 may include one or more of silicon nitride, silicon oxide, silicon oxynitride, and photoresist.

[0086] In some examples of this embodiment, the pattern material layer 150 may also include doping elements. The doping elements may be one or more of boron and phosphorus elements to increase the hardness of the pattern material layer 150. In the actual preparation process, an etchable material layer can be prepared first and then doped to form a pattern material layer 150 including doping elements. Alternatively, in-situ doping can also be performed during the preparation of the etchable material to form a pattern material layer 150 including doping elements.

[0087] In this embodiment, the material of the pattern material layer 150 includes a photoresist. The steps of preparing the pattern material layer 150 may include: coating a raw material including a photoresist on the first encapsulation body. Wherein, the photoresist may be a positive photoresist or a negative photoresist. It can be understood that after exposure treatment and development treatment, the removed part of the negative photoresist is the unexposed part, while the removed part of the positive photoresist is the exposed part. Further, the steps of preparing the pattern material layer 150 may further include: performing boron doping and phosphorus doping on the raw material including the photoresist.

[0088] In some examples of this embodiment, in the step of coating a raw material including a photoresist on the first encapsulation body, the coating may be performed by means such as spraying, knife coating or spin coating.

[0089] It can be understood that in addition to the photosensitive component, the photoresist usually also has a solvent. In some examples of this embodiment, after coating the raw material including the photoresist, a drying step is further included to remove the solvent component in the photoresist, so that the photoresist is preliminarily shaped. Wherein, the temperature for drying the photoresist material layer may be 120°C, 125°C, 130°C, 135°C, 140°C or 150°C. The temperature for drying the photoresist material layer may also be within the range of any two of the above temperatures. The drying duration is 10 min to 15 min. Wherein, the duration for drying the photoresist material layer is 10 min, 11 min, 12 min, 13 min, 14 min or 15 min. The duration for drying the photoresist material layer may also be within the range of any two of the above times.

[0090] In some examples of this embodiment, the thickness of the pattern material layer 150 may be controlled to be 120 μm to 1000 μm. For example, the thickness of the prepared pattern material layer 150 is controlled to be 125 μm, 130 μm, 150 μm, 250 μm, 400 μm, 600 μm, 800 μm or 1000 μm. The thickness of the prepared pattern material layer 150 may also be within the range between any two of the above thicknesses. In some embodiments, controlling the thickness of the pattern material layer 150, for example, between 120 μm and 140 μm, can ensure sufficient subsequent filling space and will not affect the overall thickness of the encapsulation structure.

[0091] Step S3, performing an etching treatment on the pattern material layer.

[0092] Figure 4 shows based on Figure 3Schematic diagram of a structure obtained by etching on the basis of the shown structure. Among them, the etching process refers to removing part of the material in the pattern material layer 150 through a solution, reactive ions, or other means. Compared with traditional technologies, forming the pattern layer 151 based on the pattern material layer 150 through the etching process can form openings without introducing special-shaped molds, effectively reducing the process cost and preparation difficulty. Refer to Figure 4 As shown, after etching the pattern material layer 150, a pattern layer 151 and an opening located in the pattern layer 151 are formed, and this opening is the connection hole 152.

[0093] In this embodiment, corresponding to the pattern material layer 150 including photoresist, the steps of etching the pattern material layer 150 include an exposure process and a development process. Among them, the exposure light used in the exposure process can be ultraviolet light, and its specific wavelength can be selected corresponding to the photoinitiator in the photoresist component. The development process can be carried out by soaking or washing with a photoresist developer.

[0094] In some examples of this embodiment, during the exposure process of the pattern material layer 150, the entire pattern material layer 150 can be irradiated with an exposure light source, and part of the exposure light source is masked with a mask, so that only part of the pattern material layer 150 is exposed to form the pattern layer 151. It can be understood that in this step, the connection hole 152 in the pattern layer 151 is determined by the exposed area of the pattern material layer 150. For example, for positive photoresist, the exposed area of the pattern material layer 150 is the connection hole 152 of the pattern layer 151, and for negative photoresist, the exposed area of the pattern material layer 150 is complementary to the connection hole 152 of the pattern layer 151.

[0095] Figure 5 Shows Figure 4 A top view of the shown structure, which shows the shape of the connection hole 152 of the pattern layer 151 and the positional relationship between the connection hole 152 of the pattern layer 151 and the connection pad 110. Refer to Figure 5 As shown, the connection hole 152 of the pattern layer 151 is a hole located in the pattern layer 151 and penetrating the pattern layer 151. There are multiple connection pads 110, and all the multiple connection pads 110 are exposed from this connection hole 152.

[0096] Refer to Figure 5 As shown, this connection hole 152 is located in the pattern layer 151, the connection hole 152 penetrates the pattern layer 151, and the periphery of the connection hole 152 is enclosed by the pattern layer 151. Optionally, the cross-section of this connection hole 152 is rectangular. In some other examples, the cross-section of this connection hole 152 can also be an irregular shape or a regular shape such as a circle or a hexagon.

[0097] In some examples of this embodiment, there are multiple connection pads 110, which are arranged in an array. The distance between the outermost connection pad 110 and the hole wall of the connection hole 152 is more than half of the distance between adjacent connection pads 110. This can prevent contact with the pattern layer 151 during subsequent welding of the connecting member, and improve the welding quality of the connecting member.

[0098] In some examples of this embodiment, the distance between the hole wall of the connection hole 152 and the outermost connection pad 110 is ≥200 μm. Optionally, the distance between the hole wall of the connection hole 152 and the outermost connection pad 110 is 200 μm to 1000 μm.

[0099] Figure 5 The schematic diagram of the distance between the hole wall of the rectangular connection hole 152 and the connection pad 110 is marked. Refer to Figure 5 As shown, the minimum distance between the long side of the connection hole 152 and the connection pad 110 is d 1 , and the minimum distance between the short side of the connection hole 152 and the connection pad 110 is d 2 . The width of the connection pad 110 is the maximum value of the distance between two points on the edge of the connection pad 110. For example Figure 5 as shown, the connection pad 110 is circular, and the width of the connection pad 110 is the diameter d of the connection pad 110. Optionally, d 1 ≥d / 2, and / or d 2 ≥d / 2. Further optionally, d 1 is 200 μm to 1000 μm, and / or d 2 is 200 μm to 1000 μm.

[0100] It can be understood that in this step S3, the connection hole 152 for assisting in package positioning can be formed by etching the etchable material, avoiding the introduction of special-shaped molds used in the traditional technology, and reducing the process cost and preparation difficulty.

[0101] Step S4, connect the second package to the connection pad.

[0102] Figure 6 shows the structure diagram of setting the second package on the basis of the structure shown in Figure 4 .

[0103] Refer to Figure 6As shown, the second package includes a connecting member 160. There are multiple connecting members 160, and the number of connecting members 160 is the same as the number of connection pads 110, and the positions of the connecting members 160 correspond to those of the connection pads 110 one by one. Further, the second package may further include a second package body 170, in which there is a second chip structure, and the connecting member 160 is connected to the second package body 170. Among them, the connecting member 160 may protrude from the second package body 170.

[0104] In some examples of this embodiment, in the step of connecting the second package to the connection pad, the connecting member 160 in the second package is aligned and connected to the connection pad 110 in the first package. Further, the step of connecting the connecting member 160 of the second package to the connection pad 110 includes: aligning the second package and the first package, and passing the connecting member 160 through the connection hole 152 of the pattern layer 151 and connecting it to the connection pad 110.

[0105] Among them, the connection hole 152 of the pattern layer 151 is used to assist in aligning the second package and the first package, so that the connecting member 160 can be more accurately connected to the connection pad 110. It can be understood that the connecting member 160 is disposed on the surface of the second package and protrudes, so when the connecting member 160 is aligned and connected to the connection pad 110, other areas of the second package will be blocked by the pattern layer 151 and temporarily fixed.

[0106] Refer to Figure 6 As shown, in some examples of this embodiment, the pattern layer 151 contacts the second package body 170 to support the second package body 170. Further, in order to improve the strength of the pattern layer 151, the pattern layer 151 can be doped. For example, if the material of the pattern layer 151 includes one or more of silicon oxide, silicon nitride, silicon oxynitride, and photoresist, then before connecting the second package to the connection pad, the pattern layer 151 is doped. The doping element used for the doping process can be one or more of boron element and phosphorus element to improve the density of the pattern layer 151 and the support strength.

[0107] Further, in some other examples, the second package body 170 may not contact the pattern layer 151, and at this time, the pattern layer 151 may not be doped to further simplify the manufacturing process.

[0108] Step S5, removing the pattern layer.

[0109] Figure 7 Shows in Figure 6 The structural schematic diagram of removing the pattern layer 151 on the basis of the structure shown. Refer to Figure 7As shown, the pattern layer 151 originally located between the second package and the first package is removed, and there is a relatively sufficient space between the second package and the first package. It can be understood that the connector 160 of the second package is still aligned and connected to the connection pad 110 of the first package.

[0110] In some examples of this embodiment, since the pattern layer 151 includes a photoresist, the step of removing the pattern layer 151 may include: using a photoresist remover to dissolve the pattern layer 151. The photoresist remover is a reagent that can dissolve the photoresist. It can be understood that common photoresists all have their corresponding photoresist removers, and the specific photoresist remover can be selected according to the type of photoresist, and the present disclosure does not specifically limit the type of the photoresist remover.

[0111] Step S6, preparing a support layer for covering the connecting piece.

[0112] Figure 8 Shown in Figure 7 The structural schematic diagram of preparing the support layer 180 based on the structure shown in FIG. The support layer 180 is located between the first package and the second package, and entirely covers the connector 160 on the second package.

[0113] Combination Figures 5 to 8 When preparing the pattern layer 151, the spacing between the hole wall of the connection hole 152 of the pattern layer 151 and the connection pad is more than half of the spacing between adjacent connection pads, which can avoid the connection member 160 from being damaged by the pattern layer 151 during the process of welding to the connection pad 110. In addition, since the support layer 180 is prepared after the connection member 160 is welded to the connection pad 110, the support layer 180 will not damage the connection member 160. Therefore, through this preparation method, the welding quality between the connection member 160 and the connection pad 110 can also be effectively improved.

[0114] In some examples of this embodiment, the material of the support layer 180 is different from the material of the pattern layer 151 .

[0115] In some examples of this embodiment, the step of forming the support layer 180 may include: filling a support material into a gap between the first package and the second package to form a support material layer, the support material layer covering the connector 160 on the second package, and the support material layer contacting the first package and the second package; and then curing the support material layer to form the support layer 180.

[0116] In some examples of this embodiment, the thermal expansion coefficient of the support layer 180 is between the thermal expansion coefficient of the first package and the thermal expansion coefficient of the second package to improve the warping problem caused by the large difference in thermal expansion coefficients between the first package and the second package.

[0117] In some examples of this embodiment, the material of the support layer 180 may include a molding compound. For example, the molding compound may be selected from epoxy resin or silicone resin. Epoxy resin has the characteristics of fast setting, high strength, and resistance to water and oxygen. In this embodiment, the method for preparing the support layer 180 is an injection molding process. In some other embodiments, the method for preparing the support layer 180 may also be a molded underfill process.

[0118] Thus, through steps S1 to S6, the preparation method of the encapsulation stack structure can be completed.

[0119] Furthermore, the present disclosure also provides an encapsulation stack structure, which includes:

[0120] A first encapsulation member, the first encapsulation member includes connection pads;

[0121] A second encapsulation member, the second encapsulation member includes a connection member, and the connection member is welded on the connection pads;

[0122] A support layer, the support layer is filled between the first encapsulation member and the second encapsulation member, and the support layer covers the connection member in the second encapsulation member.

[0123] In some examples of this embodiment, the first encapsulation member further includes a first encapsulation main body, the connection pads are arranged on the surface of the first encapsulation main body, the second encapsulation member further includes a second encapsulation main body, the connection member is arranged on the surface of the second encapsulation main body and protrudes from the second encapsulation main body, and the support layer contacts the first encapsulation main body and the second encapsulation main body.

[0124] In some examples of this embodiment, the first encapsulation main body includes a first molding layer and an interposer base layer, the first molding layer surrounds the interposer base layer, and the support layer is arranged on the first molding layer and the interposer base layer.

[0125] In some examples of this embodiment, the first molding layer is flush with the connection pads.

[0126] In some examples of this embodiment, the connection pads are flush with the interposer base layer.

[0127] In some examples of this embodiment, the support layer includes a support substrate and a support filler, the first molding layer includes a first molding substrate and a first molding filler, the materials of the support substrate and the first molding substrate are the same, and the particle size of the support filler is smaller than the particle size of the first molding filler. By using a support filler with a smaller particle size, it helps to improve the fluidity of the support substrate and further improve the void problem that may occur in the support layer.

[0128] In some examples of this embodiment, the second encapsulation main body further includes a second molding layer, the connection member protrudes from the second molding layer, and the support layer contacts the second molding layer.

[0129] In some examples of this embodiment, the support layer includes a support substrate and a support filler, the second encapsulation layer includes a second encapsulation substrate and a second encapsulation filler, the materials of the support substrate and the second encapsulation substrate are the same, and the particle size of the support filler is smaller than that of the second encapsulation filler. By using a support filler with a smaller particle size, it helps to improve the fluidity of the support substrate and further improve the void problem that may occur in the support layer.

[0130] In some examples of this embodiment, the connection pad is disposed on the intermediate base layer, and the support layer is in contact with the intermediate base layer. The support layer, the intermediate base layer, and the second encapsulation body jointly enclose the connecting member.

[0131] In some examples of this embodiment, the coefficient of thermal expansion of the support layer is between the coefficient of thermal expansion of the first encapsulation member and the coefficient of thermal expansion of the second encapsulation member.

[0132] In the above encapsulation stack structure, the support layer is filled between the first encapsulation member and the second encapsulation member, which can effectively seal the space between the first encapsulation member and the second encapsulation member and improve the reliability of the encapsulation.

[0133] Please note that the above embodiments are for illustrative purposes only and do not imply a limitation to the present disclosure.

[0134] It should be understood that unless there is a clear description in this article, the execution of the steps does not have a strict order limit, and these steps can be executed in other orders. Moreover, at least a part of the steps can include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least a part of other steps or sub-steps or stages of other steps.

[0135] Each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other.

[0136] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

Claims

1. A method for preparing an encapsulated stack structure, characterized in that, it comprises the following steps: providing a first encapsulation member and a second encapsulation member, the first encapsulation member including a connection pad, and the second encapsulation member including a connection member; preparing a pattern layer on the first encapsulation member to expose the connection pad; welding the connection member on the second encapsulation member to the connection pad; removing the pattern layer; filling a support layer covering the connection member between the first encapsulation member and the second encapsulation member; wherein, the step of forming the pattern layer includes: preparing a pattern material layer covering the connection pad on the first encapsulation member; performing a doping treatment on the pattern material layer, and the doping elements used in the doping treatment include one or more of boron element and phosphorus element; etching the pattern material layer to obtain an opening exposing the connection pad, thereby forming the pattern layer.

2. The method for preparing an encapsulated stack structure according to claim 1, characterized in that, the first encapsulation member further includes a first encapsulation main body, the connection pad is disposed on the surface of the first encapsulation main body, the second encapsulation member further includes a second encapsulation main body, the connection member is disposed on the surface of the second encapsulation main body and protrudes from the second encapsulation main body, and the support layer contacts the first encapsulation main body and the second encapsulation main body.

3. The method for preparing an encapsulated stack structure according to claim 2, characterized in that, the first encapsulation main body includes an intermediate base layer and a first encapsulation layer, the first encapsulation layer surrounds the intermediate base layer, and the connection pad is disposed on the intermediate base layer; the support layer is prepared on the intermediate base layer and the first encapsulation layer.

4. The method for preparing an encapsulated stack structure according to claim 1, characterized in that, there are a plurality of connection pads, the plurality of connection pads are arranged in an array, and the distance between the outermost connection pad and the inner wall of the opening of the pattern material layer is more than half of the distance between adjacent connection pads.

5. The method for preparing an encapsulated stack structure according to any one of claims 1 to 4, characterized in that, the material of the support layer is different from that of the pattern layer.

6. The method for preparing an encapsulated stack structure according to claim 5, characterized in that, the preparation step of the support layer includes: filling a support material layer into the gap between the first encapsulation member and the second encapsulation member, and the support material layer covers the connection member; performing a curing treatment on the support material layer to form the support layer.

7. The method for preparing an encapsulated stack structure according to claim 5, characterized in that, the pattern layer includes silicon oxide, silicon nitride, silicon oxynitride or photoresist; and / or, the support layer includes an encapsulation material.

8. The method for preparing an encapsulated stack structure according to claim 7, characterized in that, the pattern layer includes photoresist, and the step of removing the pattern layer includes: dissolving the pattern layer with a photoresist remover.

9. The method for preparing an encapsulated stack structure according to any one of claims 1 to 4 and 6 to 8, characterized in that, The coefficient of thermal expansion of the support layer is between the coefficient of thermal expansion of the first package and the coefficient of thermal expansion of the second package.

10. An encapsulation stack structure, characterized in that, comprising: a first package, the first package including connection pads; a second package, the second package including a connecting member, the connecting member being welded to the connection pads; a support layer, filled between the first package and the second package, and the support layer covering the connecting member; wherein, the first package includes a first molding layer and an interposer base layer, the first molding layer surrounding the interposer base layer, the support layer being disposed on the first molding layer and the interposer base layer; the support layer includes a support substrate and support fillers, the first molding layer includes a first molding substrate and first molding fillers, the support substrate is the same as the first molding substrate, and the particle size of the support fillers is smaller than the particle size of the first molding fillers.

11. The encapsulation stack structure according to claim 10, characterized in that, the first package further includes a first package body, the connection pads being disposed on the surface of the first package body, the second package further includes a second package body, the connecting member being disposed on the surface of the second package body and protruding from the second package body, and the support layer contacting the first package body and the second package body.

12. The encapsulation stack structure according to claim 10, characterized in that, the second package includes a second molding layer, the second molding layer including a second molding substrate and second molding fillers, the support substrate is the same as the second molding substrate, and the particle size of the support fillers is smaller than the particle size of the second molding fillers.

13. The encapsulation stack structure according to any one of claims 10 to 12, characterized in that, the coefficient of thermal expansion of the support layer is between the coefficient of thermal expansion of the first package and the coefficient of thermal expansion of the second package.

Images