WO2022022431A1

WO2022022431A1 - System-in-package structure and manufacturing method therefor, and electronic device

Info

Publication number: WO2022022431A1
Application number: PCT/CN2021/108316
Authority: WO
Inventors: 马会财; 佘勇; 肖甜
Original assignee: 华为技术有限公司
Priority date: 2020-07-30
Filing date: 2021-07-26
Publication date: 2022-02-03
Also published as: CN114068332A

Abstract

The present application relates to the technical field of semiconductor encapsulation, and in particular to a system-in-package structure and a manufacturing method therefor, and an electronic device. The manufacturing method for a system-in-package structure in the present application comprises the following steps: providing a template, the template being provided with a through hole; filling the through hole with a conductive material; providing a substrate, the substrate being provided with a pad; and the sintered conductive material forming a conductive column, one end of which is electrically connected to the pad. The manufacturing method in the present application has a simple process flow, is efficient, is reliable, has a low cost, and is easily popularized and applied. The present application can alleviate the problems of a high cost, a low efficiency and a complicated operation existing in an existing encapsulation method.

Description

System-in-package structure, method for making the same, and electronic device

This application claims the priority of the Chinese patent application with the application number of 202010750420.7 and the application title of "System Level Package Structure and its Fabrication Method and Electronic Equipment", which was submitted to the China Patent Office on July 30, 2020, the entire contents of which are incorporated by reference in this application.

technical field

The present application relates to the technical field of semiconductor packaging, and in particular, to a system-in-package structure, a manufacturing method thereof, and an electronic device.

Background technique

In recent years, with the continuous evolution and development of integrated circuit technology, there are more and more integrated functions, and electronic products are increasingly developing towards miniaturization, intelligence, high performance and high reliability. The integrated circuit packaging not only affects the performance of integrated circuits, electronic modules and even the whole machine, but also restricts the miniaturization, cost reduction and reliability of the entire electronic system. Among them, System In a Package (SiP) technology makes the integration of electronic components higher and higher, which can combine a large number of electronic devices, such as multiple active electronic components with different functions and optional passive components A single standard package that is assembled together to perform a certain function to form a system or subsystem. The system-in-package module has the characteristics of miniature size and low power consumption, and can be widely used in wireless communication modules, portable communication products and other fields.

In an existing system-in-package module, such as a double-sided system-in-package module, a certain switching scheme is required to lead the signal of the substrate to the outside of the module for communication. Existing methods for exporting the signals of the substrate to the outside of the module for communication include: arranging solder balls on both sides of a frame board (FB), where one solder ball is connected to the laminated circuit in the substrate, and the other is connected to the laminated circuit in the substrate. Solder balls are interconnected with external circuits; alternatively, balls are mounted on the substrate, and interconnections with external circuits are achieved through the ball-mounting part; or, copper posts are electroplated on the substrate, and the terminals are exposed on the copper posts to connect with external circuits. Realize interconnection; or, use laser or mechanical processing to generate copper column array to realize interconnection with external circuits. However, these existing methods still have the problems of complicated process, low efficiency or high cost, which need to be further improved.

Application content

The purpose of the present application is to provide a system-level packaging structure, a manufacturing method thereof, and an electronic device, which have simple process flow, high efficiency, reliability, low cost, and easy popularization and application.

According to a first aspect of the present application, a method for fabricating a system-in-package structure is provided, comprising the following steps: providing a template, wherein the template is provided with a through hole; filling the through hole with a conductive material; providing a substrate, the The substrate is provided with a pad; the sintered conductive material forms a conductive column, and one end of the conductive column is electrically connected to the pad.

The manufacturing method of the system-level package structure uses a template with through holes, that is, a template method, to sinter and fabricate a conductive column, and electrically connect one end of the conductive column to a pad on the substrate, so that the pad on the substrate is The formation of conductive pillars has the characteristics of simple process, high efficiency, reliability and low cost, which can alleviate the complex process, low efficiency, high cost or difficult application of the existing system-level packaging structure manufacturing method to the conductive pillars. The space between them is small and other scenes.

According to a second aspect of the present application, a system-in-package structure is provided, comprising:

a substrate, the substrate is provided with a pad; a conductive column, one end of the conductive column is electrically connected to the pad, and the other end of the conductive column is used for electrical connection with an external circuit; wherein, the conductive column is connected to the conductive material The conductive material is formed by sintering, and the conductive material is filled in the through holes of the template, and the through holes of the template are arranged corresponding to the pads.

As described in the foregoing first aspect regarding the fabrication method of the system-in-package structure, the system-in-package structure and the fabrication method of the system-in-package structure are based on the same application concept, and therefore at least have the same characteristics as the fabrication method of the system-in-package structure. For all the features and advantages described, the system-in-package structure obtained by the method for fabricating the system-in-package structure has the effects of reliable performance and low cost, which will not be described in detail here.

According to a third aspect of the present application, an electronic device is provided, including the system-in-package structure or the system-in-package structure fabricated by the foregoing fabrication method.

As described in the foregoing first aspect regarding the system-in-package structure and the second aspect regarding the system-in-package structure, the electronic device, the foregoing system-in-package structure and its fabrication method are based on the same application concept, and therefore at least have the same All the features and advantages described in the system-in-package structure and its fabrication method will not be described in detail here.

The technical solution provided by this application can achieve the following beneficial effects:

In the system-in-package structure and its manufacturing method provided by the present application, a template with a through hole is used in the packaging process, a conductive material is filled in the through hole, and the conductive material is sintered to form a conductive column. One end of the substrate is electrically connected to the pad of the substrate, so that a conductive column can be formed on the substrate to lead out the signal of the substrate. It uses a conductive material to form conductive pillars on the substrate through a template method to lead out signals from the substrate, which can alleviate the problems of long time and low efficiency of the existing copper plating on the substrate, and can alleviate the existing through-molded vias (TMV). The method cannot achieve high aspect ratio, small-pitch conductive column arrays and the high cost of lasers, which can alleviate the problem of easy delamination of the interface existing in the existing transfer board (FB) method. It is an efficient, low-cost, high-reliability method A method for fabricating a double-sided system-in-package structure of a conductive column array with high aspect ratio and small pitch can be realized.

Therefore, the electronic device including the system-in-package structure of the present application has at least the same advantages as the above-mentioned system-in-package structure and the manufacturing method thereof, and details are not described herein again.

It is to be understood that the foregoing general description and the following detailed description are exemplary only and do not limit the application.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present application more clearly, the following briefly introduces the accompanying drawings that need to be used in the embodiments of the present application. For those of ordinary skill in the art, without creative work, the Additional drawings can be obtained from these drawings.

FIG. 1 is a schematic structural diagram of an electronic device provided by an exemplary embodiment of the present application;

FIG. 2 is a schematic flowchart of a method for manufacturing a system-in-package structure provided by an exemplary embodiment of the present application;

FIG. 3 is a schematic structural diagram of a substrate provided by an exemplary embodiment of the present application;

FIG. 4 is a schematic structural diagram of a substrate provided with a conductive column array according to an exemplary embodiment of the present application;

FIG. 5 is a schematic structural diagram of a template provided by an exemplary embodiment of the present application;

FIG. 6 is a schematic structural diagram of a template provided by another exemplary embodiment of the present application;

FIG. 7 is a schematic structural diagram of a template provided by another exemplary embodiment of the present application;

FIG. 8 is a schematic flowchart of a method for fabricating a system-in-package structure provided by another exemplary embodiment of the present application;

9 is a schematic flowchart of a method for manufacturing a system-level packaging structure provided in Embodiment 1 of the present application;

FIG. 10 is a schematic diagram of a system-in-package structure provided by an embodiment of the present application;

Fig. 11 is a schematic diagram of the system-in-package structure provided by Comparative Example 1; in Fig. 11(a), the conductive pillars in the system-in-package structure are boss structures, and in Fig. 11(b), the conductive pillars in the system-in-package structure It is a drum-shaped structure;

12 is a schematic diagram of a system-in-package structure provided by Comparative Example 2;

13 is a schematic flowchart of a method for fabricating a system-level packaging structure provided in Embodiment 2 of the present application;

14 is a schematic flowchart of a method for manufacturing a system-level packaging structure provided in Embodiment 3 of the present application;

FIG. 15 is a schematic diagram of a system-in-package structure according to Embodiment 4 of the present application.

Among them, the reference numerals are described as follows:

1-housing; 2-system-in-package structure; 3-battery; 4-substrate; 401-first surface; 402-second surface; 5-electronic component; 6-pad; 7-template; 8-through hole ; 9-conductive column; 10-solder ball; 11-first package body; 12-second package body.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description serve to explain the principles of the application.

detailed description

In order to better understand the technical solutions of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings. It should be understood that the described embodiments are only a part of the embodiments of the present application, but not all of the embodiments.

Unless otherwise defined or indicated, professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art.

In order to improve the performance of electronic products, the integration degree of integrated circuit (IC) devices and the integration degree of devices and circuits on printed circuit boards (PCB) are constantly improving. Among them, system-in-package (SiP) is a high-density integration of devices. The trend of packaging can be widely used in module system integrated chips such as central processing units, storage, communication, power management and charging of electronic products. At present, SiP is developing from single-sided to double-sided, and double-sided SiP needs to export the signal of the substrate to the outside of the module for communication through some switching scheme. For example, in the prior art, the signals of the double-sided SiP are led out from the main substrate to the bottom surface of the module through a transfer board, molded through holes, copper pillars or solder balls, or conductive structural components in the double-sided SiP. Specifically, in the prior art, the methods of extracting the signal of the substrate to the outside of the module for communication mainly include the following:

a) Set solder balls on both sides of the adapter board, by soldering the solder balls on one side of the adapter board to the substrate, the signal passes through the solder balls to the multilayer circuit in the transmission substrate, and then passes through the solder balls of the adapter board. Solder balls on the other side enable interconnection with external circuits (other or adjacent modules). However, the shortcomings of this scheme are that the adapter board scheme occupies a large area and the process is complicated. In the subsequent reflow process between the adapter board and the main board, due to the mismatch of local deformation, epoxy molding compound will occur. compound, EMC)/substrate interface delamination, in addition, there is a high risk of solder bonding.

b) First, mount balls on the substrate, and then plastic-encapsulate, and realize interconnection with external circuits by flat grinding the plastic-encapsulation layer to leak out the ball-mounting part. However, the disadvantage of this solution is that the solder balls are first implanted on the back of the substrate, which cannot meet the requirements of a large number of I/O (input/output) terminals and a small spacing.

c) Electroplating copper pillars on the substrate, and then plastic sealing, the copper pillars are leaked out by flat grinding the plastic sealing layer, and the leakage terminals are planted on the copper pillars to achieve interconnection with external circuits. However, the shortcoming of this scheme is that in the scheme of electroplating copper pillars on the substrate, the time of electroplating copper pillars increases with the height of copper pillars. When the height of copper pillars exceeds 200 μm, the plating time is longer than 3 hours, and the efficiency is low. The cost is high, and in addition, it is difficult to achieve thicker module interconnection with this solution.

d) The copper column array is generated in advance by laser or mechanical processing. One end of the copper column array is fixed on the frame, and then the other end of the copper column array is welded to the substrate, and then plastic-sealed, and the frame part is removed by flat grinding the plastic sealing layer. One end of the column array, and a ball is placed on this terminal to achieve interconnection with external circuits. However, the disadvantage of this solution is that in the surface mount technology (SMT) copper column solution on the substrate, the copper column with frame must be fabricated by machining or laser processing first. When the copper column array spacing is In the case of reducing and increasing the number, mechanical and laser processing is difficult, the production time is long, the efficiency is low, and the cost is high.

e) First, plastic-encapsulate the double-sided SiP, and then use a laser method to form a hole array on the back of the SiP, that is, through molding via (TMV), and fill the through hole with solder balls to achieve interconnection lead-out terminals (I/O terminal). However, the disadvantage of this scheme is that the TMV scheme cannot achieve applications with large thickness and small spacing (copper column array), and the cost is high; in addition, the TMV scheme uses lasers to punch holes in the plastic sealing layer, which is inefficient. ,high cost.

In view of this, in order to overcome the imperfection of the prior art, the technical solutions of the embodiments of the present application provide a system-in-package, a method for manufacturing the same, and an electronic device, so as to alleviate the process complexity of the existing method for fabricating a system-in-package structure , low efficiency, high cost or difficult to apply to metal pillars such as small spacing between copper pillars and other scenarios, to provide a fast, efficient, suitable for high aspect ratio, small spacing metal pillars lead out I A method for fabricating a system-in-package structure of the /O scheme.

In a specific embodiment, the system-in-package and its manufacturing method of the present application and the electronic device including the system-in-package structure of the present application are further described in detail below with reference to the accompanying drawings.

In order to facilitate understanding of the system-level packaging structure and the manufacturing method thereof provided by the embodiments of the present application, an application scenario thereof is first described below. The system-level packaging structure can be applied to electronic devices. Specifically, electronic devices may include, but are not limited to, mobile phones, tablet computers, laptop computers, in-vehicle computers, display screen devices (such as TVs), wearable devices such as wearable watches, smart bracelets, smart glasses, head-mounted displays, etc. There are Augmented Reality (AR) devices, Virtual Reality (VR) devices, Personal Digital Assistant (PDA), smart home products, etc. In addition, the electronic device of the present application is not limited to the above-mentioned devices, but may include newly developed electronic devices. The embodiments of the present application do not specifically limit the specific form of the above electronic device.

As an example and not a limitation, in this embodiment of the present application, the electronic device may be a mobile phone, a wearable device, a computer, a vehicle-mounted computer, or the like. The system-in-package structure provided by the embodiments of the present application can be used for radio frequency antenna modules, power management modules, charging modules, and integrated packaging modules such as mobile phones, wearable devices, computers, and car computers.

For the convenience of description, the embodiment of the present application specifically describes the electronic device by taking a mobile phone as the above-mentioned electronic device as an example. Those skilled in the art will understand, however, that the principles of the present application may be implemented in any suitably arranged electronic device. Also, descriptions of well-known functions and constructions may be omitted for clarity and conciseness.

Specifically, referring to FIG. 1 , the present application provides an electronic device in some embodiments, the electronic device includes a casing 1 , a system-in-package structure 2 and a battery 3 disposed in the casing 1 . One or more system-in-package structures 2 may be provided within the housing 1 of the electronic device. The system-in-package structure 2 may be a double-sided system-in-package structure. The system-in-package structure 2 can be applied to module system integrated chips such as central processing unit, storage, communication, power management, display module and charging of electronic equipment. The specific structure and fabrication method of the double-sided system-in-package structure 2 will be described in detail below with reference to FIGS. 2 to 15 , and will not be described in detail here.

In order to further improve the integration of the system-in-package chip, by mounting one or more electronic components (electronic components) on both sides of the package substrate, wherein the electronic components include active components and/or passive components, the double-sided package is reused substrate area, enabling higher levels of integration while achieving more reliable interconnects.

It should be pointed out that the embodiments of the present application do not limit the specific position of the double-sided system-in-package structure 2 in the electronic device or the connection with other devices, and it may have various setting forms. Exemplarily, the double-sided system-in-package structure 2 can be disposed above the battery 3, or can also be disposed below the battery 3, or can also be disposed adjacent to other devices.

It should also be noted that the structures illustrated in the embodiments of the present application do not constitute a specific limitation on the electronic device. In other embodiments of the present application, the electronic device may include more or less components than shown, or combine some components, or separate some components, or arrange different components. For example, the electronic device may also include devices such as a camera.

In some embodiments, the electronic device includes a display screen, the casing and the display screen can be fixedly connected, and the casing and the display screen can form a sealed space to accommodate devices such as a system-in-package structure, a battery, and the like.

Specifically, the display screen may be a display device such as an organic light-emitting diode display (Organic Light-Emitting Diode, OLED), a liquid crystal display (Liquid Crystal Display, LCD), etc., but is not limited to this, and other methods may also be used. It should be understood that the display screen may include a display and a touch device, the display is used for outputting display content to the user, and the touch device is used for receiving touch events input by the user on the display screen. In the embodiments of the present application, the structure and material of the display screen are not limited.

Those skilled in the art understand that, in order to provide users with required functions, an electronic device may include several devices arranged inside the device, which is not particularly limited in this application. Those skilled in the art can determine the position or location of each device according to actual needs Adjust the specific structure, etc.

The system-in-package structure and the fabrication method thereof, especially the double-sided system-in-package structure and the fabrication method thereof, will be further described below.

Referring to FIG. 2 , an embodiment of the present application provides a method for fabricating a system-in-package structure, which includes the following steps:

Provide template with through holes;

filling the conductive material in the through hole;

A substrate is provided, and the substrate is provided with pads;

The sintered conductive material forms a conductive column, and one end of the conductive column is electrically connected to the pad.

The system-in-package structure is a double-sided system-in-package structure, that is, double-sided SiP. The conductive pillars can be used to transmit electrical signals, that is, the electrical and signal interconnection between the double-sided SiP and the outside world can be realized through the conductive pillars.

In the method for fabricating a system-in-package structure provided by the embodiments of the present application, a template with a through hole is used in the packaging process, a conductive material is filled in the through hole, and the conductive material is sintered to form a conductive column. One end of the column is electrically connected to the pad of the substrate, so that a conductive column can be formed on the substrate to lead out the signal of the substrate. Therefore, in the method for fabricating the system-in-package structure, conductive pillars are formed on the substrate by sintering conductive materials such as metal paste or powder through a template method, so as to lead out signals from the substrate. The process parameters of the template method for sintering conductive pillars can be compatible with the SMT process, which can alleviate the problems of long time and low efficiency of the existing copper plating on the substrate, and can relieve the existing TMV method that cannot realize the conductive pillars with high aspect ratio and small spacing. The problem of high cost of arrays and lasers can alleviate the problem of easy delamination of the interface existing in the existing transfer plate (FB) method. Double-sided SiP fabrication method of pillar array.

Specifically, as shown in FIG. 3 , in some embodiments, the substrate 4 includes a first surface 401 and a second surface 402 arranged oppositely; one or more electronic components 5 are mounted on the first surface 401 of the substrate 4 , One or more electronic components 5 are mounted on the second surface 402 of the substrate 4 ; pads 6 are provided on the first surface 401 and/or the second surface 402 of the substrate 4 . That is, the electronic components 5 may be mounted on both the first surface 401 and the second surface 402 of the substrate 4 , the pads 6 may be provided on the first surface 401 of the substrate 4 , or the second surface of the substrate 4 402 may be provided with pads 6 , or both the first surface 401 and the second surface 402 of the substrate 4 may be provided with pads 6 . The pad 6 can be used for electrical connection with one end of the conductive post.

It should be understood that the substrate 4 includes a first surface 401 and a second surface 402, and the first surface 401 and the second surface 402 are disposed opposite to each other. Wherein, the first surface 401 may be the upper surface (front) of the substrate 4, and the second surface 402 may be the lower surface (back) of the substrate 4; or, the first surface 401 may be the lower surface (back) of the substrate 1, The second surface 402 may be the upper surface (front surface) of the substrate 1 . Exemplarily, for the convenience of describing the relative positional relationship of several components, the following mainly takes the first surface 401 as the upper surface (front side) of the substrate 4 and the second surface 402 as the lower surface (back side) of the substrate 4 as an example. The surface SiP and its manufacturing method are described in detail. Referring to FIG. 3 , the upper surface is the upper surface of the component, and the lower surface is the downward surface of the component. However, those skilled in the art will understand that the front side and the back side of the substrate are only relative concepts, and the embodiments of the present application do not limit the specific positions of the front side and the back side of the substrate.

In order to adapt to different application scenarios or meet different requirements, the setting positions of the above-mentioned pads 6 may have various manners. Optionally, as shown in FIG. 3 and FIG. 4 , in some embodiments, a pad 6 is provided on the back of the substrate 4 , and correspondingly, a conductive material is sintered on the back pad 6 of the substrate 4 by a template method. Conductive pillars 9 are formed. In another embodiment, when the system-in-package structure includes a multi-layer structure, pads 6 may be provided on both the front and the back of the substrate 4. Correspondingly, the conductive material is sintered on the front of the substrate 4 by a template method. Conductive pillars 9 are formed on both the pad 6 and the backside pad 6 .

It should be noted that the embodiments of the present application do not limit the specific types of the above-mentioned one or more electronic components 5 disposed on the front side and the back side of the substrate. For example, one or more of the electronic components 5 may be active and/or passive components. Exemplarily, passive components may include inductors, capacitors, resistors, filters, antennas, and the like. Exemplarily, the electronic component 5 may be a bare chip or a chip package, and the bare chip or chip package may be an analog integrated circuit chip, a digital integrated circuit chip, and may include operational amplifiers, multipliers, integrated voltage regulators, timers , signal generators, data selectors, codecs, flip-flops, counters, registers, memories, programmable logic, etc. The electronic element 5 may also be an optical element, a communication element, various types of sensors, and the like.

The substrate 4 is an important part of the packaging system. For example, the substrate 4 may provide mechanical support and electrical interconnection. Electronic components such as resistors, capacitors, inductors, processors, bare chips, packaged logic components, memories, or other secondary packaged devices may be integrated on the above-mentioned substrate 4 . In addition, the substrate can also embed passive components such as resistors, capacitors, inductors, filters, etc., to improve the packaging efficiency of the system.

In the embodiments of the present application, the electronic components may be mounted on the front and back of the substrate through various interconnection techniques of the electronic components and the substrate. For example, electronic components can be mounted on the surface of the SiP substrate by techniques such as SMT, wire bonding, automatic tape bonding, flip-chip bonding, press-fit flip-chip interconnection, etc. In addition, the connection method is not limited to the above list. out technology. Those skilled in the art can select an appropriate interconnection technology to mount specific electronic components and/or components on the surface of the SiP substrate according to actual needs, which is not limited in this application. Therefore, for the sake of simplicity and clarity, detailed descriptions of interconnection techniques for electronic components and substrates are omitted herein.

It can be understood that, in the embodiment of the present application, the provided substrate 4 is a substrate 4 with one or more electronic components 5 arranged on the front and back, and with pads 6 arranged on the front and/or back.

Specifically, in some embodiments, as shown in FIGS. 3 to 5 , the above-mentioned substrate 4 is provided with a plurality of pads 6, and the plurality of pads 6 form a pad array; the above-mentioned template 7 is provided with a plurality of through holes 8, A plurality of through holes 8 form a through hole array; through the arrangement of the plurality of through holes 8, a plurality of conductive pillars 9 can be formed, and the plurality of conductive pillars 9 form a conductive pillar array; the through hole array is arranged corresponding to the pad array, so that all the The formed conductive column array is electrically connected to the pad array correspondingly. Wherein, the backside of the substrate 4 may be provided with a pad array, or both the front and the backside of the substrate 4 may be provided with a pad array.

It should be understood that the above-mentioned plurality of pads 6 are arranged at intervals, correspondingly, the above-mentioned plurality of through holes 8 are also arranged at intervals, and correspondingly, the above-mentioned plurality of conductive pillars 9 are also arranged at intervals. In addition, the arrangement or position, shape structure, size, etc. of the plurality of through holes 8 are set corresponding to the pad array on the substrate, so that each conductive column 9 in the formed conductive column array can Correspondingly connected to each pad 6 in the pad array. In the specific setting, the pads 6 are isolated from each other. The so-called phase isolation means that there is a certain distance between two adjacent pads 6 and they are not in contact. Correspondingly, they are connected to each pad 6 The conductive pillars 9 are also isolated from each other, that is, there is a certain distance between two adjacent conductive pillars 9 and are not in contact, so that there is no signal transmission between adjacent conductive pillars 9 . Therefore, it is possible to avoid a good isolation effect between the lead terminals, avoid a short circuit phenomenon caused by contact, and ensure that each device can work stably.

Specifically, in some embodiments, the template 7 may be made of a material that can withstand a certain high temperature and can be reused. In this way, the template can be maintained to have certain mechanical properties or performance during the sintering process, and can be reused many times, thereby reducing the cost. The specific material type of the template 7 can be various types, for example, the template 7 can be made of silicone resin, ceramics, stainless steel and other materials, and the prepared template 7 can withstand a certain high temperature, for example, can withstand a high temperature of about 250°C , and can be reused. In addition, the materials of the template 7 are not limited to the ones listed above, and other materials can also be selected, which are not limited in the embodiments of the present application.

When making the above-mentioned template 7 , various forming or drilling methods can be used to form the template 7 with an array of through holes according to the pad array on the substrate 4 . In the embodiment of the present application, the through-hole array and the template 7 may be integrally formed, or the template 7 may be fabricated first, and then holes are formed on the template to form the through-hole array. The embodiments of the present application do not limit the specific manner of forming the through-hole array. Exemplarily, the through-hole array is formed by using any one of mechanical perforation, photolithography, and the like.

Specifically, in some embodiments, the through-hole arrays on the template 7 are in one-to-one correspondence with the pad arrays on the substrate 4 , and the opening size, spacing, and position of the through-holes 8 need to be based on the actual substrate 4 . The arrangement, size, etc. of the pad array are set.

In the specific setting, the opening size of the through hole 8 is in the range of 10 μm-1 mm, further can be 50 μm-1 mm, further can be 100 μm-0.9 mm, and further can be 200 μm-0.8 mm, typical but non-limiting, for example, can be 10 μm, 20 μm, 40 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1 mm, and any value in the range of any two of these point values.

In the specific setting, the distance between two adjacent through holes 8 ranges from 10 μm to 1 mm, further can be 50 μm-1 mm, further can be 100 μm-0.9 mm, and further can be 500 μm-0.8 mm, typical but non-limiting For example, it can be 10 μm, 20 μm, 40 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1 mm and any two of these point values. any value of .

It should be noted that, the opening size of the above-mentioned through hole 8 is determined or adapted according to the cross-sectional shape of the through hole. For example, the cross-sectional shape of the through hole 8 can be a circle, a square, an ellipse, a polygon or other regular/irregular shapes, etc. Correspondingly, the cross-sectional shape of the formed conductive column 9 can be a circle, a square, an ellipse, Polygons or other regular/irregular shapes, etc. When the cross-sectional shape of the through-hole 8 is circular, the opening size of the through-hole 8 can be expressed as the diameter of the through-hole (circle diameter); when the cross-sectional shape of the through-hole 8 is oval, the above-mentioned through-hole 8 The opening size of the ellipse can be expressed as the long diameter (long diameter) of the ellipse, that is, the distance between the longest two points in the ellipse; when the cross-sectional shape of the through hole 8 is a square, the opening size of the through hole 8 can be expressed as It is the side length of a square, etc., which will not be listed here.

The diameter of the through hole 8 and the distance between two adjacent through holes 8 are set according to the pad array on the substrate 4 to be packaged. Within the range of the distance between them, it can meet practical application requirements, has strong adaptability, and can make a certain distance between adjacent conductive pillars 9, which can avoid short-circuit phenomenon caused by contact and ensure that each device can work stably. It can also alleviate the problem that the existing system-in-package method cannot realize the conductive pillar array with high aspect ratio and small pitch.

It should be noted that, as shown in FIG. 5 and FIG. 6 , the embodiments of the present application do not limit the specific shape and structure of the through hole 8 and the conductive column, which may be a circle, a square, an ellipse, a polygon, etc., or other The shape of the conductive column, which is not described in detail here, can realize the electrical and signal interconnection between the substrate and the outside. Any shape of the conductive column falls within the protection scope of the present application.

The thickness of the template 7 can be determined according to the thickness of the bottom surface of the actual double-sided SiP product. For example, in specific settings, the thickness of the template 7 is in the range of 10 μm-1 mm, further may be 50 μm-1 mm, further may be 100 μm-0.9 mm, further may be 500 μm-0.8 mm, typical but non-limiting, for example, may be 10μm, 20μm, 40μm, 50μm, 60μm, 70μm, 80μm, 100μm, 150μm, 200μm, 300μm, 400μm, 500μm, 600μm, 700μm, 800μm, 900μm, 1mm and any two of these point values in the range any value. The thickness of the template 7 refers to the thickness of the template in the vertical direction, which can be understood as the height of the template.

It should be understood that the thickness (height) of the above-mentioned template 7 may be the height (depth of the through hole) of the through hole 8 . Herein, "aspect ratio" refers to the ratio between the depth of the through hole and the opening size of the through hole, eg, the diameter of the through hole.

The diameter of the above-mentioned through holes 8 is compatible with the diameter of the formed conductive pillars 9 , and the spacing between the above-mentioned two adjacent through-holes 8 corresponds to the spacing between the formed two adjacent conductive pillars 9 . In addition, the height of the through hole 8 and the height of the formed conductive pillar 9 may be compatible, or, in actual operation, according to the condition of the filled conductive material or the operation error, etc., the formed conductive pillar 9 There may also be a slight difference between the height and the height diameter of the through hole 8 . The specific dimensions of the formed conductive pillars 9 will not be described in detail here, and reference may be made to the foregoing description on the dimensions of the through holes.

In specific settings, the upper and lower dimensions of the through holes 8 may be the same or different. For example, the through hole 8 may be a through hole structure with the same size of each part. Alternatively, the through hole 8 may be a stepped hole, and the stepped hole includes an upper part of the hole structure and a lower part of the hole structure, wherein the diameter of the upper part of the hole structure is larger than that of the lower part of the hole structure, or the diameter of the upper part of the hole structure is smaller than that of the lower part of the hole structure The diameter of the pore structure. Alternatively, the through hole 8 may be a hole structure whose diameter decreases sequentially from top to bottom, or a hole structure whose diameter increases sequentially from top to bottom. Of course, in other embodiments, the specific shape and structure of the through hole 8 is not limited, and it may also have other structure and shape structure, which will not be described in detail here. In addition, the shape and structure of each through hole 8 in the through hole array may be the same or different. For example, the through hole array may be composed of circular through holes, or may also be composed of circular through holes and oval through holes.

In the specific setting, the specific form of the through-hole array can also have various types according to the pad array on the substrate. For example, the array of vias can be single-row, multi-row, or random. As shown in FIG. 5 , in some embodiments, the through-hole arrays may be arranged in two rows on the top and bottom of the substrate, and one column on the left and right, respectively, and form an annular structure of through-hole arrays.

As shown in FIG. 6 , in other embodiments, the through hole arrays may be arranged in a row on the upper and lower sides of the substrate, and arranged in a column on the left and right, respectively, and form a ring-shaped through hole array.

As shown in FIG. 7 , in other embodiments, the through-hole array may be a through-hole array in which the upper, middle, and lower portions of the substrate are arranged in one row, and the left, middle, and right are arranged in a column, and the template is divided into four parts.

It should be noted that the specific form of the through-hole array is not limited to the several structural forms listed above. In the case of meeting the needs of the packaging substrate or the system-level packaging structure, the specific form of the through-hole array can also adopt other structural forms. There is no special restriction on the application. For example, in some practical situations, the number of conductive pillars and pads included in the system-in-package structure may be more than one hundred, so the number and arrangement shown in the accompanying drawings are for illustration only, and do not limit the present application.

In the embodiment of the present application, the conductive material is filled in the above-mentioned through-hole array, and after sintering, a conductive column array can be formed on the pad array of the substrate. Wherein, the conductive material may be a metal material and/or a non-metal material, and the formed conductive column may be a metal column, a non-metal column or a composite column.

Specifically, in some embodiments, the conductive material includes one or more of metal materials, carbon materials, or polymer materials. That is, the conductive material may be a metal material, a non-metal material, or a mixed material of a metal material and a non-metal material, wherein the non-metal material may be a carbon material, a polymer material, or the like. Further, the carbon material may be graphite, graphene, carbon nanotube (CNT), carbon fiber and other carbon materials.

The form of the conductive material includes powder or paste.

Further, the conductive material may be metal powder or a paste containing metal powder.

Optionally, the conductive material may be copper powder, silver powder, aluminum powder, solder paste such as SAC305 solder paste, nano-copper paste, nano-silver paste, and the like. The use of these conductive materials has a wide range of sources, strong practicability, easy sintering into conductive columns, and high conductivity, which can meet the required requirements for conduction and signal transmission.

Optionally, the conductive material can be a carbon material such as graphite, graphene or carbon nanotubes, or a mixed material of carbonaceous materials such as graphite, graphene or carbon nanotubes and metal materials such as copper powder, silver powder, etc., or It is a mixed material of polymer material and metal material, etc.

Specifically, in some embodiments, the conductive pillars are metal pillars, non-metallic pillars, or composite pillars composed of metal materials and non-metallic materials. Further, the metal pillars may be solder pillars, copper pillars, silver pillars, etc., or may also be carbon material pillars, or may also be composite pillars formed by compounding carbon materials and metal materials. Therefore, the metal pillars help to realize the electrical and signal interconnection between the double-sided SiP structure and the outside world.

It should be understood that several specific types of conductive materials or conductive pillars are exemplarily listed above. However, the specific types of conductive materials or conductive pillars are not limited to the ones listed above. When required for signal interconnection, the specific type of the conductive material or the specific type of the conductive column may also adopt other forms, which are not particularly limited in this embodiment of the present application.

Specifically, in some embodiments, the material of the pad can also be of various types, for example, the material of the pad includes copper, aluminum or tungsten, and the surface of the pad can be sprayed with tin, immersion silver or immersion gold, etc. This embodiment of the present application also does not make any special restrictions on this.

The specific sintering process parameters for sintering the conductive material to form the conductive pillars can be the same as the reflow soldering process parameters of the backside electronic components of the double-sided SiP structure. In addition, the sintering process conditions also need to be adjusted according to the type of the specific conductive material. Specifically, in some embodiments, the sintering temperature is 100°C-280°C, further can be 150°C-280°C, further can be 160°C-260°C, further can be 180°C-240°C, typical but not limited For example, it can be 100°C, 120°C, 150°C, 160°C, 180°C, 190°C, 200°C, 220°C, 240°C, 250°C, 260°C, 280°C and any two of these point values. Any value in the range that constitutes.

The above-mentioned conductive material can use the existing common lead-free solder. Therefore, in this sintering operation, the metal powder or metal paste in the through-hole array of the template can be sintered under the lead-free solder reflow temperature curve, and then the through-hole array can be sintered. The metal powder or metal paste is cured and sintered. The sintering temperature of the above-mentioned metal powder or paste is compatible with the temperature of the common lead-free solder reflow process. Therefore, the specific operation method or operation conditions of this sintering step will not be described in detail, which can be adjusted by those skilled in the art according to the actual situation. .

Specifically, in some embodiments, as shown in FIG. 8 , filling the conductive material in the through hole includes: firstly disposing the template on the transfer carrier, and then filling the conductive material in the through hole.

The through holes on the template are through holes passing through the template. Therefore, in order to facilitate the filling of the conductive material into the through holes, the template needs to be fixed on the transfer carrier before filling. Then, the conductive material is filled in the through hole, so as to use the transfer carrier plate to play a certain role of supporting and ensuring the amount of the conductive material filled in the through hole.

In addition, after filling, the template filled with conductive material and the transfer carrier can be transferred to the substrate together, so that the upper surface of the template (the surface on the side away from the transfer carrier) is inverted and in contact with the substrate, and the template is placed on the substrate. The through hole array is aligned with the pad array on the substrate. After the alignment is completed, the transfer carrier located on the lower surface of the template (the surface close to the side of the transfer carrier) can be removed, and then sintered.

It should be noted that the operation sequence of removing the transfer carrier plate can be adjusted, which can be adapted according to the operation sequence of the specific packaging method. Exemplarily, after the filling is completed, the conductive material may be sintered first, and then the template of the conductive column and the transfer carrier may be transferred to the substrate together, so that the upper surface of the template is inverted and contacted with the substrate, and the template is placed on the substrate. The through-hole array is aligned with the pad array on the substrate, and after the alignment is completed, the transfer carrier and the template are removed in turn.

The specific implementation manner of filling the conductive material in the through hole can also have various manners. For example, in some embodiments, please continue to refer to FIG. 8 , the conductive material may be filled in the through holes by means of printing. During the printing process, it may need to be repeated several times according to the size of the through hole, such as diameter and height, to ensure that the through hole is filled or filled with a certain amount of metal powder or paste, and then the upper surface of the template can be cleaned to ensure that there is no metal powder. or paste residue. In addition, in other embodiments, the conductive material may also be filled in the through hole in other manners, which will not be described in detail here.

Specifically, in some embodiments, please continue to refer to FIG. 8 , after the sintered conductive material forms a conductive column, and one end of the conductive column is electrically connected to the pad, the method for fabricating the system-in-package structure further includes: assembling the tape The substrate with the conductive posts is plastic-sealed to form a plastic-sealing layer; the part of the plastic-sealing layer corresponding to the conductive posts is removed to expose the conductive posts. The plastic encapsulation layer and the substrate are firmly combined, which ensures the reliability of the encapsulation.

It can be understood that in this method, after sintering to form a conductive column array on the pad array of the substrate, those skilled in the art can use suitable plastic packaging technology and equipment to complete the above plastic packaging process according to actual needs. The conductive pillars are exposed in the manner of , which is not limited in this embodiment of the present application. Exemplarily, after the conductive column array is formed on the pad array of the substrate, a plastic sealing process can be performed on the double-sided SiP to form a plastic sealing layer. The balls are implanted to form interconnections, and then the subsequent process steps are completed for the double-sided SiP, and finally a double-sided SiP structure is obtained.

In order to realize the interconnection between the double-sided SiP structure and the outside world, the conductive pillar array needs to be exposed outside the plastic package. For example, the conductive pillar array may be exposed by flat grinding the plastic encapsulation layer, thinning process, and the like. Exemplarily, the above-mentioned forming process of the plastic sealing layer may be an injection molding process, a transfer molding process or a screen printing process, etc. Of course, it may also be other forming processes, which are not limited in the embodiments of the present application.

Optionally, in some embodiments, please continue to refer to FIG. 8 , after removing part of the plastic encapsulation layer corresponding to the conductive posts to expose the conductive posts, the method further includes: planting balls on the conductive posts. That is, solder balls are formed on the conductive pillars by means of ball mounting, and the solder balls may be located on the top of the conductive pillars, and may also be located on the tops and sidewalls of the conductive pillars. In addition, in other embodiments, in order to adapt to different application scenarios or meet different requirements, the ball-mounting step may not be performed, that is, the other end of the metal column is directly connected to the external circuit to realize the double-sided SiP structure and the outside world. electrical and signal interconnection.

In a specific embodiment, the manufacturing method of the system-in-package structure includes the following steps:

Silicone resin, ceramics, stainless steel and other materials are used to make a template that can withstand high temperature of 250°C and can be reused. The template is provided with an array of through holes corresponding to the array of pads on the backside of the double-sided SiP substrate. Among them, the opening size and spacing of the through holes can be set according to the pad array of the actual product. For example, the opening size of the through holes can be any size in the range of 10μm-1mm, and the spacing between two adjacent through holes can be Any size in the range of 10μm-1mm. The shape of the through hole can be a square hole, a circular hole, an oval hole and other holes of any shape. The upper and lower dimensions of the through hole may be the same or different, for example, the upper surface dimension of the through hole is larger than the lower surface dimension, or the lower surface dimension of the through hole is larger than the upper surface dimension and the like. The thickness of the template (through hole depth) can be determined according to the thickness of the actual double-sided SiP product. For example, the thickness of the template can be any size in the range of 10 μm to 1 mm.

Then, the template can be pre-fixed on the transfer carrier plate with tape, and then the metal powder or paste containing metal powder can be filled into the through hole array of the template by printing. The sintering temperature of the metal powder or paste is the same as that of common The lead-free solder reflow process temperature is compatible. During the printing process, it may be necessary to repeat several times according to the diameter and depth of the through hole to ensure that the through hole is filled or filled with a certain amount of metal powder paste, and then the upper surface of the template is (Surface on the side facing away from the transfer carrier) is cleaned to ensure that no metal powder or paste remains.

After filling, pick up the template and the transfer carrier together, mount the upper surface of the template filled with conductive material on the double-sided SiP substrate, and align the through-hole array of the template with the pad array on the substrate position, remove the transfer carrier after the alignment is completed.

After the alignment is placed and the transfer carrier is removed, the metal powder or metal paste in the template through hole can be sintered. The sintering process parameters are the same as the reflow soldering process parameters of the double-sided SiP backside device. For example, the sintering temperature can be 100℃- In the range of 280°C, after the sintering step is completed, the conductive material in the through hole has been cured and sintered. The sintering process step can be before, after or at the same time as the double-sided SiP backside device surface mount.

After sintering, the template can be removed and demolded to form a conductive column array, that is, one end of the conductive column is electrically connected to the pad. Then, a plastic sealing process can be performed on the back of the double-sided SiP. After plastic sealing, the conductive column array is leaked through the flat grinding plastic sealing layer, and the ball is planted on the other end of the conductive column to form an interconnection, and then the subsequent process steps are completed for the double-sided SiP. Double-sided SiP structure.

It can be seen from the above that the manufacturing method of the system-level packaging structure of the embodiment of the present application is simple to operate, easy to implement, efficient, reliable, low in cost, and easy to realize large-scale production. In addition, the method can solve the problem that some existing methods such as TMV method cannot realize conductive column arrays with high aspect ratio and small spacing, and can solve the problems of long time and low efficiency of the existing copper electroplating method.

It should be noted that, in the present application, unless otherwise specified, each operation step may be performed in sequence, or may not be performed in sequence. The embodiments of the present application do not limit the sequence of steps for preparing the system-in-package structure, which may be adjusted according to the actual production process. For example, the template filled with conductive material can be transferred to the substrate of double-sided SiP (referred to as transfer), and then sintered, and then the template can be removed (referred to as demolding); or, it can be transferred first, and then demolded , and then sintering; alternatively, sintering can be performed first, then transfer, and then demolding.

The specific fabrication methods of several different system-level packaging structures will be described in detail below with reference to the accompanying drawings. The effects of the present application and the order of the operation steps in the production method are described below with specific examples, but the protection scope of the present application is not limited by the following examples.

Example 1

FIG. 9 shows a schematic flowchart of the manufacturing method of the system-in-package structure provided in Embodiment 1, as shown in FIG. 9 .

S100. Template making: a silicon resin material is used to make a template that can withstand a high temperature of 250°C and can be reused. The template is provided with a through-hole array corresponding to the pad array on the backside of the double-sided SiP substrate. The through-hole array can be up and down. The through-hole arrays are respectively arranged in two rows and left and right are arranged in one column. The thickness of the prepared template may be 0.15mm or 0.3mm, the diameter of the through holes on the template may be 0.2mm, and the distance between two adjacent through holes may be 0.4mm.

S200, filling: pre-fix the prepared template on the transfer carrier board, and then fill the SAC305 solder paste or nano-copper paste into the through-hole array of the template by printing to fill the through-holes, and then the template Clean the top surface.

S300, transfer: after filling, take out the template and the transfer carrier together, transfer the upper surface of the template filled with conductive material to the double-sided SiP substrate, and make the through-hole array of the template and the solder on the substrate Align the disk array, and remove the transfer carrier after the alignment is complete.

S400, sintering: after the alignment is placed and the transfer carrier is removed, the conductive material in the template through hole can be sintered under the lead-free solder reflow temperature curve. For example, the sintering temperature can be in the range of 150°C-280°C, and the sintering step is completed. The conductive material in the rear via has been cured and sintered.

S500, demoulding: after sintering, the template can be removed to perform demolding, and a conductive column array is formed on the pad array of the substrate. The diameter of each conductive column in the formed conductive column array is 0.2 mm, and the height is 0.15 mm or 0.285 mm.

S600, plastic sealing and other post-processing: After demolding, the double-sided SiP can be plastic-sealed to form a plastic-sealing layer. After plastic-sealing, the conductive column array is leaked out through the flat-grinding plastic-sealing layer. structure.

The double-sided system-in-package structure prepared in Example 1 of the present application is shown in FIG. 10 .

Comparative Example 1

Using any existing TMV method, the double-sided system-in-package structure is prepared.

The double-sided system-in-package structure prepared in Comparative Example 1 is shown in FIG. 11 . In FIG. 11( a ), the conductive pillars 9 in the double-sided system-in-package structure 2 are boss structures, and in FIG. 11( b ), the conductive pillars 9 in the double-sided system-in-package structure 2 are drum-shaped structures.

Comparative Example 2

Using any of the existing electroplating conductive pillar methods, such as electroplating metal pillar method, or SMT metal pillar method, the preparation of the double-sided system level packaging structure is carried out.

The double-sided system-in-package structure prepared in Comparative Example 2 is shown in FIG. 12 . In FIG. 12 , the conductive pillars 9 in the double-sided system-in-package structure 2 are cylindrical structures.

The method for fabricating the system-level packaging structure provided in Embodiment 1 of the present application includes post-processing such as S100 template fabrication, S200 filling, S300 transfer, S400 sintering, S500 demoulding, and S600 plastic sealing. In Example 1, a double-sided system-level package structure fabricated by sintering nano-copper paste or solder paste by a template method is shown in FIG. 10 below. The morphology of the conductive column 9 sintered under the reflow temperature of lead-free solder is 90° in verticality, the conductive column 9 can be a regular cylindrical shape, and the internal structure of the conductive column 9 is not dense, that is, the inner structure of the conductive column 9 is not dense. The tissue density will generally be less than 100%, eg the density is 60%-95% or 70%-90%.

As shown in Fig. 11(a) and Fig. 11(b), in Comparative Example 1, the double-sided system-in-package structure 2 prepared by the existing TMV method, the conductive 9-pillars are generally in the shape of bosses with inconsistent upper and lower openings or in the shape of a double-sided system-in-package structure 2. Drum-shaped structure, in this way, when the distance between adjacent conductive columns 9 is small, it is easy to connect the two conductive columns, which easily leads to the occurrence of short circuit and affects the transmission of signals. As shown in FIG. 12 , in Comparative Example 2, the double-sided system-in-package structure 2 prepared by the existing electroplating conductive pillar or SMT conductive pillar method can produce a cylindrical conductive pillar 9 , but the obtained conductive pillar 9 The internal structure is dense, and generally the density of the conductive column 9 is 100%, which will increase the cost, and the operation time is long and the efficiency is low.

It can be seen from this that the method for fabricating the system-level packaging structure provided by the embodiment of the present application directly fabricates the conductive column array on the double-sided SiP substrate by the template method, with few process steps, and the conductive column forming process is compatible with the reflow process. The conductive column array is stable and reliable, has low cost and high efficiency, and is suitable for the preparation of conductive column arrays with high aspect ratio and small spacing. Therefore, it is possible to alleviate the high cost of laser drilling in the existing TMV solution and the inability to realize the preparation of conductive column arrays with high aspect ratio and small spacing, or can alleviate the problems of the existing metal column electroplating process taking a long time and high cost .

Example 2

FIG. 13 shows a schematic flowchart of the manufacturing method of the system-in-package structure provided in Embodiment 2, as shown in FIG. 13 .

S100. Template making: a silicon resin material is used to make a template that can withstand a high temperature of 250°C and can be reused. The template is provided with a through-hole array corresponding to the pad array on the backside of the double-sided SiP substrate. The through-hole array can be up and down. The through-hole arrays are respectively arranged in two rows and left and right are arranged in one column. The thickness of the prepared template may be 0.4 mm or 0.5 mm, the diameter of the through holes on the template may be 0.3 mm, and the distance between two adjacent through holes may be 0.2 mm.

S200, filling: pre-fix the prepared template on the transfer carrier, and then fill the nano-silver paste or nano-copper paste into the through-hole array of the template by printing, the through-holes can be filled, and then the template is filled Clean the top surface.

S300. Sintering: After filling, the conductive material in the template through hole can be sintered under the lead-free solder reflow temperature curve. For example, the sintering temperature can be in the range of 150℃-280℃. After the sintering step is completed, the conductive material in the through hole can be sintered The material has been cured and sintered.

S400, transfer: after sintering, transfer the template with the conductive column array to the double-sided SiP substrate, and align the through hole array of the template with the pad array on the substrate, so that the formed conductive column array Each of the conductive pillars is correspondingly electrically connected to each pad in the pad array.

S500, demoulding: after the transfer, the template can be removed, that is, demoulding. In the conductive column array formed on the pad array of the substrate, each conductive column has a diameter of 0.3 mm and a height of 0.4 mm or 0.5 mm.

The method for fabricating a system-level package structure provided in Embodiment 2 of the present application includes post-processing such as S100 template fabrication, S200 filling, S300 sintering, S400 transfer, S500 demoulding, and S600 plastic sealing. The main difference between Example 2 and Example 1 is that, in the manufacturing process, Example 2 first sinters the conductive column array, and then transfers the template with the conductive column array to the substrate; The template filled with conductive material is transferred to the substrate, and then sintered to produce the array of conductive pillars.

The double-sided system-in-package structure prepared in Example 2 can also be shown in FIG. 10 . Compared with Comparative Example 1 and Comparative Example 2, Example 2 can also achieve the same or similar effects as Example 1, which will not be repeated here.

Example 3

FIG. 14 shows a schematic flowchart of the manufacturing method of the system-in-package structure provided in Embodiment 3, as shown in FIG. 14 .

S100. Template production: use stainless steel and other materials to make a template that can withstand high temperature of 250 ° C and can be reused. The template is provided with a through-hole array corresponding to the pad array on the back of the double-sided SiP substrate. The through-hole array can be up and down. The through-hole arrays are arranged in two or three rows respectively, and in the form of one or two columns on the left and right. The thickness of the prepared template may be 0.6 mm, the diameter of the through holes on the template may be 0.4 mm, and the distance between two adjacent through holes may be 0.15 mm.

S200. Filling: pre-fix the prepared template on the transfer carrier, and then fill the solder paste or nano-silver paste or nano-copper paste into the through-hole array of the template by printing, so that the through-holes can be filled. Then clean the upper surface of the template.

S300, transfer: after filling, transfer the template filled with conductive material to the double-sided SiP substrate, and align the through-hole array of the template with the pad array on the substrate, which can be removed after the alignment is placed Transfer the carrier plate.

S400, demoulding: after the transfer, the template can be removed, that is, demoulding.

S500, sintering: after demolding, the conductive material can be sintered under the lead-free solder reflow temperature curve, for example, the sintering temperature can be in the range of 150°C-280°C, and the conductive material has been cured and sintered after the sintering step is completed. In the conductive column array formed on the pad array of the substrate, each conductive column has a diameter of 0.4 mm and a height of 0.6 mm.

S600, plastic sealing and other post-processing: After sintering, the double-sided SiP can be plastic-sealed to form a plastic-sealing layer. After plastic-sealing, the conductive column array is leaked out through the flat-grinding plastic-sealing layer, and then the double-sided SiP structure is finally obtained through subsequent operation steps. .

The method for fabricating a system-level package structure provided in Embodiment 3 of the present application includes S100 template fabrication, S200 filling, S300 transfer, S400 demoulding, S500 sintering, S600 plastic sealing and other post-processing. The main difference between Example 3 and Example 1 is that, in the manufacturing process, Example 3 first transfers the template filled with conductive material to the substrate, and then demolds it, that is, pre-sets the conductive column array on the substrate, and then Conducting sintering to fabricate a conductive column array; while in Example 1, a template filled with conductive materials was first transferred to a substrate, then sintered to fabricate a conductive column array, and then demolded.

Compared with Comparative Example 1 and Comparative Example 2, Example 3 can also achieve the same or similar effects as Example 1, which will not be repeated here.

Example 4

The manufacturing process of the method for manufacturing a system-level packaging structure provided in this Embodiment 4 may be the manufacturing process provided by any of the foregoing Embodiments 1-3, and the difference is:

In Example 4, both the upper surface (front side) and the lower surface (back side) of the substrate are provided with pad arrays, a conductive column array is formed on the pad array on the upper surface of the substrate, and a pad array is formed on the lower surface pad array of the substrate There are arrays of conductive pillars. In addition, solder balls are formed on the conductive pillars, and the solder balls can be formed on the conductive pillars by a ball-mounting process. The electrical and signal interconnection between the double-sided system-in-package structure and the outside world or other package structures can be realized through solder balls.

The double-sided system-in-package structure prepared in Example 4 of the present application is shown in FIG. 15 . The double-sided system-in-package structure may be a first package body 11 , the first package body 11 and the second package body 12 are stacked in a vertical direction, the upper surface of the first package body 11 and the lower surface of the second package body 12 In contrast, one or more electronic components 5 may be provided on both the upper surface and the lower surface of the first package body 11 , and one or more electronic components 5 may be provided on the second package body 12 . A conductive pillar array is formed on the pad array on the upper surface of the substrate of the first package body 11 , and solder balls 10 are formed on the conductive pillars 9 in the conductive pillar array. The solder balls 10 are located on the upper surface of the first package body 11 and the second Between the lower surfaces of the two packages 12, and the two ends of the solder balls 10 are respectively connected to the conductive pillars 9 and the lower surfaces of the second package 12, thus, through the arrangement of the conductive pillar array and the solder balls 10, the Signal transmission between the first package body 11 and the second package body 12 .

In addition, a conductive column array is formed on the pad array on the lower surface of the substrate 4 in the first package body 11 , and solder balls 10 are formed on the conductive column 9 in the conductive column array. Through the arrangement of the conductive column array and the solder balls 10 , the signal transmission between the first package 11 and other packages can also be realized.

It should be noted that the term "and/or" or "/" used in this document is only an association relationship to describe associated objects, indicating that there can be three kinds of relationships, for example, A and/or B, which can mean that: exist independently A, there are both A and B, and there are three cases of B alone.

As used in this application, "first," "second," and similar terms do not denote any order, quantity, or importance, but are merely used to distinguish the various components. Words like "connected" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", etc. is only used to represent the relative positional relationship. When the absolute position of the object to be described changes, the relative position Relationships may also change accordingly. It will also be understood that when an element such as a layer or a substrate is referred to as being "on" or "under" another element, it can not only be directly connected "on" or "under" the other element, but also Indirectly connected "on" or "under" another element through intervening elements.

It should be noted that a part of this patent application file contains content protected by copyright. Except for making copies of the patent files of the Patent Office or the contents of the recorded patent files, the copyright owner reserves the right to copyright.

Claims

A method for manufacturing a system-level packaging structure, comprising the following steps:

A template is provided, and the template is provided with through holes;

filling the conductive material in the through hole;

providing a substrate, the substrate is provided with pads;

The sintered conductive material forms a conductive pillar, and one end of the conductive pillar is electrically connected to the pad.
The method for fabricating a system-in-package structure according to claim 1, wherein the sintered conductive material forms a conductive column, and one end of the conductive column is electrically connected to the pad comprising:

transferring the template filled with the conductive material onto the substrate so that the through holes correspond to the pads;

and then sintering, so that the conductive material forms the conductive column, and one end of the conductive column is electrically connected to the pad;

Remove the template.
The method for fabricating a system-in-package structure according to claim 1, wherein the sintered conductive material forms a conductive column, and one end of the conductive column is electrically connected to the pad comprising:

sintering the template filled with the conductive material, so that the conductive material forms the conductive pillar;

transferring the template with the conductive pillars to the substrate, so that the through holes correspond to the pads, and one end of the conductive pillars is electrically connected to the pads;

Remove the template.
The method for fabricating a system-in-package structure according to claim 1, wherein the sintered conductive material forms a conductive column, and one end of the conductive column is electrically connected to the pad comprising:

transferring the template filled with the conductive material onto the substrate so that the through holes correspond to the pads;

remove the template;

Then, sintering is performed so that the conductive material forms the conductive pillar, and one end of the conductive pillar is electrically connected to the pad.
The method for fabricating a system-in-package structure according to claim 1, wherein filling the conductive material in the through hole comprises:

The template is set on the transfer carrier first, and then the conductive material is filled in the through holes.
The method for fabricating a system-in-package structure according to claim 5, wherein the conductive material is filled in the through hole by means of printing.
The method for fabricating a system-in-package structure according to claim 1, wherein the pad comprises a plurality of pads, the plurality of pads form a pad array, and the through hole comprises a plurality of through holes, The plurality of through holes form a through hole array, the conductive pillars include a plurality of conductive pillars, and the plurality of conductive pillars form a conductive pillar array;

The through hole array is configured corresponding to the pad array, so that the formed conductive pillar array is electrically connected to the pad array correspondingly.
The method for fabricating a system-in-package structure according to claim 1, wherein the substrate comprises a first surface and a second surface disposed opposite to each other;

One or more electronic components are mounted on the first surface of the substrate, and one or more electronic components are mounted on the second surface of the substrate;

The pads are provided on the first surface and/or the second surface of the substrate.
The method for fabricating a system-in-package structure according to claim 1, wherein the conductive pillars comprise metal pillars, non-metallic pillars, or composite pillars composed of metal materials and non-metallic materials.
The method for fabricating a system-in-package structure according to claim 1, wherein the conductive material comprises one or more of a metal material, a carbon material or a polymer material;

The form of the conductive material includes powder or paste.
The method for fabricating a system-in-package structure according to claim 1, wherein the size of the opening of the through hole ranges from 10 μm to 1 mm;

The through holes include a plurality of through holes, and the distance between two adjacent through holes ranges from 10 μm to 1 mm.
The method for fabricating a system-in-package structure according to claim 1, wherein the thickness of the template ranges from 10 μm to 1 mm.
The method for fabricating a system-in-package structure according to claim 1, wherein the sintering temperature is 100°C-280°C.
The method for fabricating a system-in-package structure according to any one of claims 1-13, wherein a conductive column is formed on the sintered conductive material, and one end of the conductive column is electrically connected to the pad. After the connection, the method further includes: plastic-sealing the substrate with the conductive posts to form a plastic-sealing layer;

Parts of the plastic encapsulation layer corresponding to the conductive pillars are removed to expose the conductive pillars.
The method for fabricating a system-in-package structure according to claim 14, wherein after removing the part of the plastic encapsulation layer corresponding to the conductive pillars to expose the conductive pillars, the method further comprises: Including: planting balls on the conductive posts.
A system-in-package structure, comprising:

a substrate, the substrate is provided with a pad;

a conductive column, one end of the conductive column is electrically connected to the pad, and the other end of the conductive column is used for electrical connection with an external circuit;

Wherein, the conductive pillars are formed by sintering a conductive material, and the conductive material is filled in the through holes of the template, and the through holes of the template are arranged corresponding to the pads.
The system-in-package structure of claim 16, wherein the substrate comprises a first surface and a second surface disposed opposite to each other;

one or more electronic components are mounted on the first surface, and one or more electronic components are mounted on the second surface;

The first surface and/or the second surface are provided with the pads.
The system-in-package structure of claim 16, wherein the pads comprise a plurality of pads, the plurality of pads form an array of pads, the conductive pillars comprise a plurality of conductive pillars, the plurality of bonding pads a conductive column array is formed;

The conductive column array is electrically connected to the pad array correspondingly.
The system-in-package structure according to claim 16, wherein the conductive pillars comprise metal pillars, non-metallic pillars or composite pillars composed of metal materials and non-metallic materials.
The system-in-package structure according to claim 16, wherein the diameter of the conductive pillars ranges from 10 μm to 1 mm;

The conductive pillars include a plurality of conductive pillars, and the distance between two adjacent conductive pillars ranges from 10 μm to 1 mm.
The system-in-package structure according to claim 16, wherein the height of the conductive pillars ranges from 10 μm to 1 mm.
The system-in-package structure according to any one of claims 16-21, wherein the system-in-package structure further comprises a plastic sealing layer encapsulated outside the substrate, and the conductive pillars are exposed on the plastic sealing layer the exterior.
The system-in-package structure according to any one of claims 16-21, wherein the system-in-package structure further comprises solder balls disposed on the conductive pillars.
An electronic device, characterized in that it comprises a system-in-package structure fabricated by the fabrication method according to any one of claims 1-15 or the system-in-package structure according to any one of claims 16-23.