Packaging structure
阅读说明:本技术 封装结构 (Packaging structure ) 是由 石磊 于 2019-07-26 设计创作,主要内容包括:一种封装结构,所述塑封层中具有若干半导体芯片和位于每个半导体芯片一侧的无需屏蔽的电子元件;位于半导体芯片与塑封层之间的第一屏蔽层和第二屏蔽层,所述第一屏蔽层包覆所述半导体芯片的非功能面和侧壁表面,所述第二屏蔽层位于第一屏蔽层和塑封层之间且完全覆盖所述半导体芯片的非功能面和侧壁上的第一屏蔽层表面,所述第二屏蔽层能覆盖所述第一屏蔽层中厚度不均匀以及边缘覆盖不好的地方,从而使得第一屏蔽层和第二屏蔽层两者构成的整体屏蔽层是完整的,提高了屏蔽的效果。并且,本发明实现了半导体芯片与无需进行屏蔽的电子元件的集成封装,提高了封装结构的性能。(A packaging structure is provided, wherein a plastic packaging layer is provided with a plurality of semiconductor chips and electronic elements which are not required to be shielded and are positioned on one side of each semiconductor chip; be located first shielding layer and second shielding layer between semiconductor chip and the plastic envelope layer, first shielding layer cladding the non-functional face and the lateral wall surface of semiconductor chip, the second shielding layer is located between first shielding layer and the plastic envelope layer and covers completely first shielding layer surface on the non-functional face and the lateral wall of semiconductor chip, the second shielding layer can cover the place that thickness is inhomogeneous and edge cover is not good in the first shielding layer to make the whole shielding layer that both constitute of first shielding layer and second shielding layer complete, improved the effect of shielding. In addition, the invention realizes the integrated packaging of the semiconductor chip and the electronic element without shielding, and improves the performance of the packaging structure.)
1. A package structure, comprising:
the pre-packaged panel comprises a plastic packaging layer, wherein the plastic packaging layer is provided with a plurality of semiconductor chips and electronic elements which are located on one side of each semiconductor chip and do not need shielding, each semiconductor chip comprises a functional surface and a non-functional surface opposite to the functional surface, the functional surface is provided with a plurality of first bonding pads, the surface of the electronic elements which do not need shielding is provided with a plurality of second bonding pads, and the first bonding pads and the second bonding pads are exposed by the plastic packaging layer;
the first shielding layer and the second shielding layer are positioned between the semiconductor chip and the plastic packaging layer, the first shielding layer covers the surface of the non-functional surface and the surface of the side wall of the semiconductor chip, and the second shielding layer is positioned between the first shielding layer and the plastic packaging layer and completely covers the surface of the first shielding layer on the non-functional surface and the surface of the side wall of the semiconductor chip;
a first external contact structure on the back of the pre-cover plate and connected with the first bonding pad;
and a second external contact structure connected to the second pad on the back surface of the pre-cover plate.
2. The package structure of claim 1, wherein the first shielding layer is formed by a sputtering process, the first shielding layer further covers at least a portion of a surface of the carrier around between the semiconductor chips, and the second shielding layer is formed by a selective plating process, a dispensing process, or a screen printing process.
3. The package structure of claim 2, wherein the material of the first shielding layer is copper, tungsten or aluminum, and the material of the second shielding layer is copper, solder or conductive silver paste.
4. The package structure of claim 1, wherein the first shielding layer is a magnetic field shielding layer and the second shielding layer is an electric field shielding layer; or the first shielding layer is an electric field shielding layer, and the second shielding layer is a magnetic field shielding layer.
5. The package structure of claim 4, wherein the material of the electric field shielding layer is copper, tungsten, aluminum; the magnetic field shielding layer is made of CoFeB alloy, CoFeTa, NiFe, Co, CoFe, CoPt or Ni, Co and Fe alloy.
6. The package structure of claim 1, wherein the functional surface of the semiconductor chip further comprises a bottom shielding layer, the bottom shielding layer covers the entire functional surface of the semiconductor chip, the peripheral edge of the bottom shielding layer is flush with the peripheral side wall of the semiconductor chip, the first pads penetrate through the bottom shielding layer, and the first pads are isolated from the bottom shielding layer by an isolation layer; the first shielding layer is connected with the peripheral edge of the bottom shielding layer.
7. The package structure of claim 1, wherein the first external contact structure includes a rewiring layer on the back side of the pre-cover plate connected to the first pad and an external contact on the rewiring layer connected to the rewiring layer.
8. The package structure of claim 7, wherein the back side of the pre-cover board has an insulating layer thereon, the insulating layer having a first opening therein exposing the first pad surface and a second opening therein exposing the second pad surface, the rewiring layer being located in the first opening and on a portion of the insulating layer surface, the external contacts being located on the rewiring layer surface outside the first opening; the second contact structure is located in the second opening.
9. The package structure of claim 8, further comprising: and a conductive contact structure in the insulating layer electrically connecting the first shield layer with a portion of the rewiring layer.
10. An individual package structure formed by dividing the package structure according to claims 1 to 9, comprising: the semiconductor chip comprises a functional surface and a non-functional surface opposite to the functional surface, the functional surface is provided with a plurality of first bonding pads, the surface of the electronic element which does not need to be shielded is provided with a plurality of second bonding pads, and the first bonding pads and the second bonding pads are exposed out of the plastic packaging layer; the first shielding layer and the second shielding layer are positioned between the semiconductor chip and the plastic packaging layer, the first shielding layer covers the surface of the non-functional surface and the surface of the side wall of the semiconductor chip, and the second shielding layer is positioned between the first shielding layer and the plastic packaging layer and completely covers the surface of the first shielding layer on the non-functional surface and the surface of the side wall of the semiconductor chip;
the first external contact structure is positioned on the back surface of the plastic packaging layer and connected with the first bonding pad;
and a second external contact structure located on the back surface of the plastic packaging layer and connected with the second bonding pad.
Technical Field
The invention relates to the field of semiconductor manufacturing, in particular to a packaging structure with electromagnetic shielding.
Background
The rapid development of new generation electronic products pushes the integrated circuit package to develop towards high density, high frequency, miniaturization and high integration, and the high frequency chip often generates strong electromagnetic waves to cause undesirable interference or noise inside and outside the package and the chip; in addition, the density of electronic components is increasing, and the distance of transmission lines is becoming closer, so that the problem of electromagnetic interference from inside and outside the integrated circuit package is becoming more serious, and the quality, the service life and the like of the integrated circuit are also being reduced.
In electronic devices and products, Electromagnetic Interference (Electromagnetic Interference) energy is transmitted by conductive coupling and radiative coupling. In order to meet the requirement of electromagnetic compatibility, a filtering technology is required to be adopted for conductive coupling, namely an EMI filtering device is adopted for inhibiting; the radiation coupling is suppressed by shielding. The importance of the method is more prominent under the condition that the electromagnetic environment of equipment and a system is increasingly deteriorated due to the factors that the current electromagnetic spectrum is increasingly dense, the electromagnetic power density in a unit volume is sharply increased, a large number of high-level devices or low-level devices are mixed for use and the like.
An existing electromagnetic shielding solution is mainly to provide a magnetic field shielding layer on a semiconductor package structure for shielding electromagnetic interference between chips, but the effect of the existing electromagnetic shielding still needs to be improved.
Disclosure of Invention
The technical problem to be solved by the invention is how to improve the electromagnetic shielding effect of the existing packaging structure.
The invention provides a packaging structure, which is characterized by comprising:
the pre-packaged panel comprises a plastic packaging layer, wherein the plastic packaging layer is provided with a plurality of semiconductor chips and electronic elements which are located on one side of each semiconductor chip and do not need shielding, each semiconductor chip comprises a functional surface and a non-functional surface opposite to the functional surface, the functional surface is provided with a plurality of first bonding pads, the surface of the electronic elements which do not need shielding is provided with a plurality of second bonding pads, and the first bonding pads and the second bonding pads are exposed by the plastic packaging layer;
the first shielding layer and the second shielding layer are positioned between the semiconductor chip and the plastic packaging layer, the first shielding layer covers the surface of the non-functional surface and the surface of the side wall of the semiconductor chip, and the second shielding layer is positioned between the first shielding layer and the plastic packaging layer and completely covers the surface of the first shielding layer on the non-functional surface and the surface of the side wall of the semiconductor chip;
a first external contact structure on the back of the pre-cover plate and connected with the first bonding pad;
and a second external contact structure connected to the second pad on the back surface of the pre-cover plate.
Optionally, the first shielding layer is formed by a sputtering process, the first shielding layer at least covers a part of the surface of the carrier plate around the semiconductor chips, and the second shielding layer is formed by a selective plating process, a dispensing process, or a screen printing process.
Optionally, the first shielding layer is made of copper, tungsten or aluminum, and the second shielding layer is made of copper, solder or conductive silver paste.
Optionally, the first shielding layer is a magnetic field shielding layer, and the second shielding layer is an electric field shielding layer; or the first shielding layer is an electric field shielding layer, and the second shielding layer is a magnetic field shielding layer.
Optionally, the electric field shielding layer is made of copper, tungsten, or aluminum; the magnetic field shielding layer is made of CoFeB alloy, CoFeTa, NiFe, Co, CoFe, CoPt or Ni, Co and Fe alloy.
Optionally, the functional surface of the semiconductor chip is further provided with a bottom shielding layer, the bottom shielding layer covers the whole functional surface of the semiconductor chip, the peripheral edge of the bottom shielding layer is flush with the peripheral side wall of the semiconductor chip, the plurality of first bonding pads penetrate through the bottom shielding layer, and the first bonding pads are isolated from the bottom shielding layer through an isolation layer; the first shielding layer is connected with the peripheral edge of the bottom shielding layer.
Optionally, the first external contact structure includes a rewiring layer located on the back surface of the pre-cover plate and connected to the first pad, and an external contact located on the rewiring layer and connected to the rewiring layer.
Optionally, an insulating layer is disposed on the back surface of the pre-sealing panel, the insulating layer has a first opening exposing the surface of the first pad and a second opening exposing the surface of the second pad, the rewiring layer is disposed in the first opening and on a portion of the surface of the insulating layer, and the external contact is disposed on the surface of the rewiring layer outside the first opening; the second contact structure is located in the second opening.
Optionally, the method further includes: and a conductive contact structure in the insulating layer electrically connecting the first shield layer with a portion of the rewiring layer.
The invention also provides an independent packaging structure formed by dividing the packaging structure, which comprises: the semiconductor chip comprises a functional surface and a non-functional surface opposite to the functional surface, the functional surface is provided with a plurality of first bonding pads, the surface of the electronic element which does not need to be shielded is provided with a plurality of second bonding pads, and the first bonding pads and the second bonding pads are exposed out of the plastic packaging layer; the first shielding layer and the second shielding layer are positioned between the semiconductor chip and the plastic packaging layer, the first shielding layer covers the surface of the non-functional surface and the surface of the side wall of the semiconductor chip, and the second shielding layer is positioned between the first shielding layer and the plastic packaging layer and completely covers the surface of the first shielding layer on the non-functional surface and the surface of the side wall of the semiconductor chip;
the first external contact structure is positioned on the back surface of the plastic packaging layer and connected with the first bonding pad;
and a second external contact structure located on the back surface of the plastic packaging layer and connected with the second bonding pad.
Compared with the prior art, the technical scheme of the invention has the following advantages:
according to the packaging structure, the plastic packaging layer is provided with a plurality of semiconductor chips and electronic elements which are located on one side of each semiconductor chip and do not need shielding; be located first shielding layer and second shielding layer between semiconductor chip and the plastic envelope layer, first shielding layer cladding the non-functional face and the lateral wall surface of semiconductor chip, the second shielding layer is located between first shielding layer and the plastic envelope layer and covers completely first shielding layer surface on the non-functional face and the lateral wall of semiconductor chip, the second shielding layer can cover the place that thickness is inhomogeneous and edge cover is not good in the first shielding layer to make the whole shielding layer that both constitute of first shielding layer and second shielding layer complete, improved the effect of shielding. In addition, the invention realizes the integrated packaging of the semiconductor chip and the electronic element without shielding, and improves the performance of the packaging structure.
Furthermore, the second shielding layer is only positioned on the surface of the first shielding layer covering the non-functional surface and the side wall surface of the semiconductor chip, the surface of the second shielding layer is an ellipsoid, and the second shielding layer is formed through a selective electroplating process, a dispensing process or a screen printing process, so that the formed second shielding layer can better cover the first shielding layer, the place with poor coverage in the second shielding layer is prevented, the integrity of the whole shielding layer formed by the first shielding layer and the second shielding layer is further ensured, and the semiconductor chip is removed without extra masks and etching processes.
Further, the first shielding layer is a magnetic field shielding layer, and the formed second shielding layer is an electric field shielding layer; or first shielding layer is electric field shielding layer, then the second shielding layer that forms is magnetic field shielding layer, through first shielding layer and the second shielding layer that forms aforementioned structure for first shielding layer and second shielding layer shield to electric field or magnetic field respectively, thereby improved the shielding effect of shielding layer, and the second shielding layer can cover the place that thickness is inhomogeneous and edge cover is not good in the first shielding layer to make the whole shielding layer that first shielding layer and second shielding layer both constitute complete, further improved the effect of shielding.
Furthermore, after the first external contact structure and the second external contact structure are formed, the pre-sealing panel is cut to form a plurality of separated packaging structures, so that batch manufacturing of the packaging structures with the first shielding layer and the second shielding layer is realized, and production efficiency is improved.
Furthermore, a bottom shielding layer is further arranged on the functional surface of the semiconductor chip and covers the whole functional surface of the semiconductor chip, the peripheral edge of the bottom shielding layer is flush with the peripheral side wall of the semiconductor chip, a plurality of first bonding pads penetrate through the bottom shielding layer, and the first bonding pads are isolated from the bottom shielding layer through an isolation layer; when the first shielding layer is formed, the first shielding layer is connected with the peripheral edge of the bottom shielding layer. That is, in this embodiment, not only after the first shielding layer is formed, the second shielding layer is formed on the first shielding layer, so that the second shielding layer can cover the place with uneven thickness and poor edge coverage in the first shielding layer, so that the whole shielding layer formed by the first shielding layer and the second shielding layer is complete, the shielding effect is improved, and because the bottom shielding layer is further provided on the functional surface of the semiconductor chip, when the first shielding layer is formed, the first shielding layer is connected with the peripheral edge of the bottom shielding layer, so that the semiconductor chip in the package structure is completely or omnidirectionally covered by the bottom shielding layer and the first shielding layer, and thus the electric field and the magnetic field cannot enter the package structure through the bottom of the package structure to bring electromagnetic interference to the semiconductor chip, thereby realizing the omnibearing electromagnetic shielding of the semiconductor chip, the electromagnetic shielding effect is further improved.
Drawings
Fig. 1-13 are schematic structural diagrams illustrating a process of forming a package structure according to a first embodiment of the invention;
fig. 14-19 are schematic structural views illustrating a process of forming a package structure according to a second embodiment of the invention.
Detailed Description
As mentioned in the background, the effectiveness of the conventional electromagnetic shielding is still to be improved.
Research finds that the existing magnetic field shielding layer is generally formed through a sputtering process, and because the thickness of the semiconductor packaging structure is generally thick and the semiconductor packaging structure is generally rectangular, the semiconductor packaging structure is provided with a plurality of top angles and has steep side walls, when the magnetic field shielding layer covering the semiconductor packaging structure is formed through the sputtering process, the thickness of the formed magnetic field shielding layer is easily uneven, and the edge of the semiconductor packaging structure can have an uncovered condition, so that the shielding effect of the magnetic field shielding layer is difficult to guarantee.
The invention provides a packaging structure and a forming method thereof, wherein the forming method comprises the steps of bonding functional surfaces of a plurality of semiconductor chips on a carrier plate, and then forming a first shielding layer for coating the non-functional surfaces and the side wall surfaces of the semiconductor chips; correspondingly adhering the electronic element without shielding on the carrier plate at one side of each semiconductor chip, wherein the surface of the electronic element without shielding, which is provided with the second bonding pad, is opposite to the adhering surface of the carrier plate; forming a plastic packaging layer covering the second shielding layer, the electronic element without shielding and the carrier plate; peeling the carrier plate to form a pre-sealing panel, wherein a first bonding pad on a functional surface of the semiconductor chip and a second bonding pad of the electronic element which does not need shielding are exposed from the back surface of the pre-sealing panel; and forming a first external contact structure connected with the first bonding pad and a second external contact structure connected with the second bonding pad on the back surface of the pre-cover plate. Through forming the second shielding layer on first shielding layer, the second shielding layer can cover the place that thickness is inhomogeneous and edge cover is not good in the first shielding layer to make the whole shielding layer that first shielding layer and second shielding layer both constitute complete, improved shielded effect.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In describing the embodiments of the present invention in detail, the drawings are not to be considered as being enlarged partially in accordance with the general scale, and the drawings are only examples, which should not be construed as limiting the scope of the present invention. In addition, the three-dimensional dimensions of length, width and depth should be included in the actual fabrication.
Fig. 1-13 are schematic structural views illustrating a process of forming a package structure according to a first embodiment of the invention.
Referring to fig. 1 to 3, fig. 2 is a schematic cross-sectional view along a cutting line AB in fig. 1, a plurality of
An integrated circuit (not shown) is formed in the functional surface of the
The functional surface of the
The
In one embodiment, the material of the
In an embodiment, the integrated circuit in the
In this embodiment, the
Referring to fig. 4, a
The
The
The adhesive layer may be made of various materials, and in one embodiment, the adhesive layer is made of a UV glue. UV glue is a glue material that reacts to ultraviolet radiation of a particular wavelength. The UV adhesive can be divided into two types according to the change of viscosity after ultraviolet irradiation, wherein one type is a UV curing adhesive, namely, a photoinitiator or a photosensitizer in the material generates active free radicals or cations after absorbing ultraviolet light under the irradiation of ultraviolet light, and initiates the chemical reaction of monomer polymerization, crosslinking and grafting, so that the UV curing adhesive is converted from a liquid state to a solid state within several seconds, and the surface of an object contacted with the UV curing adhesive is bonded; another type of UV glue is highly viscous in the absence of UV radiation, and the cross-linking chemical bonds within the material are broken after UV radiation, resulting in a substantial decrease or loss of viscosity. The latter is the UV glue used for the adhesive layer. The adhesive layer may be formed by a film attaching process, a glue printing process, or a glue rolling process.
In other embodiments, the material of the bonding layer may also be epoxy glue, polyimide glue, polyethylene glue, benzocyclobutene glue or polybenzoxazole glue.
The
In another embodiment, referring to fig. 5, before the
Referring to fig. 6, a
In this embodiment, the
In an embodiment, the
In this embodiment, the
Research shows that the existing shielding layer needs to shield both an electric field and a magnetic field, while the existing single-layer shielding layer made of a specific material or multiple layers of shielding layers made of the same material or similar materials only have a good shielding effect on the electric field, but have a relatively weak shielding effect on the magnetic field, thereby affecting the shielding effect of the shielding layer. Thus, in other embodiments, the
Referring to fig. 5, a non-shielding
The
Signals generated in the
The
In this embodiment, after the
In another embodiment, the
In yet another embodiment, the
Referring to fig. 6, a
Through forming
In this embodiment, the
The material of the
In another embodiment, the material of the
In one embodiment, the solder is one or more of tin, tin-silver, tin-lead, tin-silver-copper, tin-silver-zinc, tin-bismuth-indium, tin-gold, tin-copper, tin-zinc-indium, or tin-silver-antimony.
In other embodiments, the
Referring to fig. 7, a
The
The
The
Referring to fig. 8 and 9, the carrier board 201 (refer to fig. 7) is peeled off to form the
The adhesive layer is removed by chemical etching, mechanical peeling, CMP, mechanical polishing, thermal baking, or the like, so that the
The back surface of the
In an embodiment, after the
Referring to fig. 10 and 11, a first external contact structure connected to the
In this embodiment, the first external contact structure includes a
In one embodiment, the formation of the
The insulating layer (first insulating layer) 121 and the insulating layer (second insulating layer) 122 further have a second opening therein to expose the surface of the second pad 402 (or a portion of the surface of the first shielding layer on the second pad 402); a second
In one embodiment, the second
In an embodiment, a conductive contact structure (not shown in the figure) is further formed on the insulating layer (first insulating layer) 121 to electrically connect the
In an embodiment, forming a connection line (not shown in the figure) in the insulating layer to electrically connect a portion of the
Referring to fig. 12 and 13, after the first external contact structure and the second external contact structure are formed, the
Each package structure 11 includes a
a first external contact structure (123 and 124) on the back surface of the
and a second
The invention realizes the batch production of the packaging structure 11 with the
Fig. 14-19 are schematic structural views illustrating a process of forming a package structure according to a second embodiment of the invention. The second embodiment differs from the first embodiment in that: the semiconductor chip comprises a semiconductor chip, a bottom shielding layer, a plurality of first bonding pads, an isolation layer and a plurality of second bonding pads, wherein the functional surface of the semiconductor chip is also provided with the bottom shielding layer, the bottom shielding layer covers the whole functional surface of the semiconductor chip, the peripheral edge of the bottom shielding layer is flush with the peripheral side wall of the semiconductor chip, the plurality of first bonding pads penetrate through the bottom shielding layer, and the first bonding pads are isolated from the bottom shielding layer through the isolation layer; when the first shielding layer is formed, the first shielding layer is connected with the peripheral edge of the bottom shielding layer. That is, in this embodiment, not only after the first shielding layer is formed, the second shielding layer is formed on the first shielding layer, so that the second shielding layer can cover the place with uneven thickness and poor edge coverage in the first shielding layer, so that the whole shielding layer formed by the first shielding layer and the second shielding layer is complete, the shielding effect is improved, and because the bottom shielding layer is further provided on the functional surface of the semiconductor chip, when the first shielding layer is formed, the first shielding layer is connected with the peripheral edge of the bottom shielding layer, so that the semiconductor chip in the package structure is completely or omnidirectionally covered by the bottom shielding layer and the first shielding layer, and thus the electric field and the magnetic field cannot enter the package structure through the bottom of the package structure to bring electromagnetic interference to the semiconductor chip, thereby realizing the omnibearing electromagnetic shielding of the semiconductor chip, the electromagnetic shielding effect is further improved.
The forming process of the semiconductor chip with the bottom shielding layer comprises the following steps: referring to fig. 14, a
In this embodiment, the isolation layer is a double-layer stacked structure, and includes a
Referring to fig. 15, the isolation layer is etched, a plurality of
The
The
In this embodiment, a first etching process is used to etch the
In other embodiments, when the isolation layer is a single-layer structure, two etching processes may be performed to form the first opening and the second opening, respectively, and the depth of the formed second opening is controlled by controlling the time of the etching process (the depth of the second opening is smaller than the thickness of the isolation layer).
Referring to fig. 16, a metal material is filled in the first openings to form
In an embodiment, the
Referring to fig. 18, fig. 18 is a schematic view of a top view structure of the
In the present application, the process of forming the
Referring to fig. 19, the
Then, peeling off the
It should be noted that other definitions or descriptions of the same or similar structures in the second embodiment as in the first embodiment are omitted in the second embodiment, and specific reference is made to the definitions or descriptions of corresponding parts in the first embodiment.
An embodiment of the present invention further provides a package structure, please refer to fig. 11 or fig. 19, including:
the pre-packaged panel (10) comprises a
the semiconductor chip package structure comprises a
a first external contact structure 12 connected to the first pad on the back surface of the pre-cover plate;
and a second
In an embodiment, the
In another embodiment, the
In an embodiment, referring to fig. 19, the functional surface of the
In one embodiment, the external contact structure includes a
An insulating layer (first insulating layer) 121 is arranged on the back surface of the pre-packaged panel, a first opening exposing the surface of the
An insulating layer (first insulating layer) 122 covering the insulating layer (first insulating layer) 121, the
In one embodiment, the method further comprises: conductive contact structures (not shown) in the insulating layer 121 electrically connecting the
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
- 上一篇:一种医用注射器针头装配设备
- 下一篇:系统级封装模块及终端设备