CN110517959B - Forming method of packaging structure - Google Patents
Forming method of packaging structure Download PDFInfo
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- CN110517959B CN110517959B CN201910676061.2A CN201910676061A CN110517959B CN 110517959 B CN110517959 B CN 110517959B CN 201910676061 A CN201910676061 A CN 201910676061A CN 110517959 B CN110517959 B CN 110517959B
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/48—Manufacture or treatment of parts, e.g. containers, prior to assembly of the devices, using processes not provided for in a single one of the subgroups H01L21/06 - H01L21/326
- H01L21/4814—Conductive parts
- H01L21/4846—Leads on or in insulating or insulated substrates, e.g. metallisation
- H01L21/4853—Connection or disconnection of other leads to or from a metallisation, e.g. pins, wires, bumps
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/50—Assembly of semiconductor devices using processes or apparatus not provided for in a single one of the subgroups H01L21/06 - H01L21/326, e.g. sealing of a cap to a base of a container
- H01L21/56—Encapsulations, e.g. encapsulation layers, coatings
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/28—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection
- H01L23/31—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection characterised by the arrangement or shape
- H01L23/3107—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection characterised by the arrangement or shape the device being completely enclosed
- H01L23/3135—Double encapsulation or coating and encapsulation
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
- H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
- H01L2224/18—High density interconnect [HDI] connectors; Manufacturing methods related thereto
Abstract
A method for forming a packaging structure provides a plurality of chips with a first plastic packaging layer, because the first plastic packaging layer is generally formed by injection molding or plastic transfer technology, the formed first plastic packaging layer has a flat surface, so that the surface of each semiconductor chip has a flat surface, when the first plastic packaging layer on a plurality of discrete semiconductor chips is adhered with a carrier plate, each semiconductor chip and the carrier plate have higher adhesive force, when a second plastic packaging layer covering a plurality of semiconductor chips is formed on the carrier plate, when the second plastic packaging layer is impacted by the pressure of injection molding or plastic transfer, the positions of all the semiconductor chips on the carrier plate can not generate offset, so that after the carrier plate is removed, when a rewiring layer connected with a bonding pad is formed on the back surface of a pre-packaged panel, the connecting position of the rewiring layer and the corresponding bonding pad can not generate offset, thereby improving the electrical connection performance between the rewiring layer and the pad.
Description
Technical Field
The invention relates to the field of semiconductor manufacturing, in particular to a forming method of a fan-out type packaging structure.
Background
The fan-in chip package is a manufacturing method that rewiring and solder ball bump preparation are performed on the whole wafer, and finally the wafer is cut into single chips. The final package size of the package is equivalent to the chip size, and the package can be miniaturized and lightened, and is widely applied to portable equipment. Although the chip size after packaging can be greatly reduced by the chip fan-in type packaging, the number of the implanted balls on a single chip is limited, and the wafer packaging form is difficult to be applied to the chip with high density I/O port number. Therefore, for a chip with a higher I/O density, if wafer level packaging is performed, in order to ensure that the chip to be packaged and the printed circuit board can be interconnected, the high density I/O must be fanned out to a low density package pin, i.e., chip fan-out type packaging is performed, and compared with the conventional chip fan-in type packaging, the chip fan-out type packaging can achieve a smaller packaging size, better electrical and thermal properties and higher packaging density.
Currently, the main processes of chip fan-out packaging include: firstly, the front surfaces (the front surfaces are the surfaces with the bonding pads) of a plurality of divided semiconductor chips are bonded on a carrier plate through adhesive tapes or adhesive layers; forming a plastic packaging layer covering the semiconductor chips on the carrier plate, and carrying out plastic packaging on the plurality of semiconductor chips on the carrier plate; stripping the carrier plate, and then re-wiring the front surface of the semiconductor chip to form a re-wiring layer connected with the bonding pad; forming a solder ball connected with the rewiring layer on the rewiring layer; and finally, cutting to form a plurality of discrete packaging structures.
However, in the packaging structure formed by the existing chip fan-out type packaging process, the electrical connection between the rewiring layer and the semiconductor chip is easy to be unstable, and the performance of the packaging structure is influenced.
Disclosure of Invention
The invention aims to solve the technical problems of improving the electrical connection stability of a rewiring layer and a semiconductor chip in a packaging structure formed by a chip fan-out type packaging process and improving the performance of the packaging structure.
The invention provides a forming method of a packaging structure, which comprises the following steps:
providing a plurality of semiconductor chips, wherein 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 bonding pads, metal bumps are formed on the surfaces of the bonding pads, the functional surface is also provided with a first plastic packaging layer, and the first plastic packaging layer covers the metal bumps;
providing a carrier plate;
bonding the first plastic packaging layers on the functional surfaces of the plurality of semiconductor chips on the carrier plate;
forming a second plastic packaging layer wrapping the non-functional surface and the side wall surface of the semiconductor chip on the carrier plate;
stripping the carrier plate to form a pre-packaged panel, wherein the first plastic packaging layer is exposed out of the back surface of the pre-packaged panel;
removing part of the first plastic packaging layer and the second plastic packaging layer on the back surface of the pre-packaged panel to expose the top surface of the metal bump;
and forming an external contact structure connected with the metal bump on the back surface of the pre-cover plate.
Optionally, the forming process of the semiconductor chip is as follows: providing a wafer, wherein a plurality of semiconductor chips are formed on the wafer, each semiconductor chip comprises a functional surface, and a bonding pad is arranged on each functional surface; forming a metal bump on the pad; forming a first plastic packaging layer covering the metal bump and the functional surface; and after the first plastic packaging layer is formed, cutting the wafer to form a plurality of discrete semiconductor chips.
Optionally, the first plastic package layer and the second plastic package layer are made of resin, and the first plastic package layer and the second plastic package layer are formed by an injection molding process or a rotational molding process.
Optionally, the size of the material particles in the first plastic package layer is smaller than the size of the material particles in the second plastic package layer.
Optionally, a portion of the first molding compound layer and the second molding compound layer on the back surface of the pre-packaged panel is removed by a chemical mechanical polishing process, so as to expose the top surface of the metal bump.
Optionally, an isolation sacrificial layer is formed on the top surface or the top and sidewall surfaces of the metal bump, and the first plastic package layer further covers the isolation sacrificial layer.
Optionally, removing a part of the first plastic package layer and the second plastic package layer on the back surface of the pre-packaged panel by using a chemical mechanical polishing process to expose the surface of the isolation sacrificial layer; and removing the isolation sacrificial layer on the top surface of the metal bump by adopting an etching process to expose the top surface of the metal bump.
Optionally, the etching process is wet etching or dry etching.
Optionally, the isolation sacrificial layer is made of silicon oxide, silicon nitride, or silicon oxynitride.
Optionally, the external contact structure includes a redistribution layer on the back of the pre-cover plate and connected to the metal bump, and an external contact on the redistribution layer and connected to the redistribution layer.
Optionally, the forming process of the redistribution layer and the external contact includes: after the carrier plate is stripped, forming a rewiring layer on the back surface of the pre-sealing panel; forming an insulating layer on the back surfaces of the rewiring layer and the pre-sealing surface plate, wherein an opening for exposing the surface of the rewiring layer part is formed in the insulating layer; an external contact is formed in the opening.
Optionally, forming the external contact structure further includes: and cutting the pre-packaged panel to form a plurality of discrete packaging structures.
Compared with the prior art, the technical scheme of the invention has the following advantages:
the forming method of the packaging structure comprises the steps of providing a plurality of semiconductor chips, wherein a functional surface of each semiconductor chip is provided with a bonding pad, a metal lug is formed on the surface of the bonding pad, the functional surface is also provided with a first plastic packaging layer, and the first plastic packaging layer covers the metal lug; bonding the first plastic packaging layers on the functional surfaces of the plurality of semiconductor chips on the carrier plate; and forming a second plastic packaging layer which coats the non-functional surface and the side wall surface of the semiconductor chip on the carrier plate. Because the first plastic package layer is generally formed by an injection molding or plastic transfer process, the formed first plastic package layer has a flat surface, so that the surface of each semiconductor chip has a flat surface, when the first plastic package layers on a plurality of discrete semiconductor chips are bonded with the carrier plate, each semiconductor chip and the carrier plate have high adhesive force, when the second plastic package layer covering a plurality of semiconductor chips is formed on the carrier plate, all the semiconductor chips cannot generate offset on the carrier plate when being impacted by the pressure of injection molding or plastic transfer, so that a pre-packaged panel is formed after the carrier plate is removed, when a rewiring layer connected with a pad is formed on the back surface of the pre-packaged panel, the connection position of the rewiring layer and the corresponding pad cannot generate offset, and the electrical connection performance between the rewiring layer and the pad is improved, thereby improving the stability and reliability of the package structure.
Further, before forming the first plastic package layer, an isolation sacrificial layer is formed on the top surface or the top and sidewall surfaces of the metal bump, and then a first plastic package layer covering the isolation sacrificial layer is formed, so that a portion of the first plastic package layer and a portion of the second plastic package layer can be removed by combining a chemical mechanical polishing process and an etching process to expose the metal bump through the specific structure, specifically, a portion of the first plastic package layer and the second plastic package layer are removed by using the chemical mechanical polishing process to expose the surface of the isolation sacrificial layer, and then the isolation sacrificial layer on the top surface of the metal bump is removed by using the etching process to expose the top surface of the metal bump, so that not only the top surface of the metal bump can be exposed through the specific structure and the specific process, but also when a portion of the first plastic package layer and the second plastic package layer are removed by using the chemical mechanical polishing process, exposed is the isolation sacrificial layer surface, and the grinding pad in the grinding equipment can not contact with the metal lug, so that grinding force can not be brought to the metal lug, the metal lug is better prevented from loosening or falling off from the bonding pad, the precision of the connecting position between the subsequently formed rewiring layer and the corresponding metal lug is further improved, and the electrical connection performance of the rewiring layer and the metal lug is further improved.
Further, the forming process of the semiconductor chip is as follows: providing a wafer, wherein a plurality of semiconductor chips are formed on the wafer, each semiconductor chip comprises a functional surface, and a bonding pad is arranged on each functional surface; forming a metal bump on the pad; forming a first plastic packaging layer covering the metal lug and the functional surface by an injection molding or rotational molding process; and after the first plastic packaging layer is formed, cutting the wafer to form a plurality of discrete semiconductor chips. When the injection molding or plastic transfer process is carried out, the bottom of the wafer is fixed in the mold, and the wafer cannot move in the mold of the injection molding or plastic transfer equipment due to the large area of the bottom of the wafer, so that the formed first plastic package layer has a flat surface.
Furthermore, the size of the material particles in the first plastic package layer is smaller than that of the material particles in the second plastic package layer formed subsequently, so that the first plastic package layer can better fill gaps between and on two sides of the metal bumps, the first plastic package layer is more tightly contacted with the side faces of the metal bumps, the fixing effect of the first plastic package layer on the metal bumps is better, and the metal bumps can be better prevented from being loosened or falling off from the bonding pad when the first plastic package layer and the second plastic package layer are flattened by adopting a chemical mechanical polishing process to expose the top surfaces of the metal bumps subsequently, and the metal bumps can be prevented from being over-polished.
Drawings
Fig. 1-19 are schematic structural diagrams illustrating a process of forming a package structure according to an embodiment of the invention.
Detailed Description
As mentioned in the background art, in the package structure formed by the conventional fan-out package process of the chip, the electrical connection between the rewiring layer and the semiconductor chip is easily unstable, which affects the performance of the package structure.
Research shows that the reason why the electrical connection between the rewiring layer and the semiconductor chip in the conventional fan-out package structure is easily unstable is: the connection position of the rewiring layer and the pad of the semiconductor chip is shifted.
Further research has found that the reason why the connection position of the rewiring layer and the pad of the semiconductor chip is shifted is: when fan-out packaging is carried out, one side of a plurality of semiconductor chips with bonding pads is bonded on a carrier plate through an adhesive tape or an adhesive layer, because the surface flatness of different semiconductor chips is different, particularly when metal bumps are also formed on the bonding pads, the surface flatness difference of different chips is larger, so that when different semiconductor chips are bonded with the carrier plate through the adhesive tape or the adhesive layer, the adhesive force between different semiconductor chips and the carrier plate is different, when a plastic package layer is formed, part of the semiconductor chips generate offset at the position on the carrier plate under the action of injection molding pressure or impact force due to insufficient adhesive force, and after the carrier plate is removed, when a re-wiring layer is formed on the plastic package layer and the front surface of the semiconductor chip, the connecting position between the re-wiring layer and the bonding pads on the semiconductor chips with offset is generated, thereby affecting the electrical connection performance of the rewiring layer and the bonding pad in the formed fan-out packaging structure.
The invention provides a packaging structure and a forming method thereof, wherein the forming method comprises the steps of providing a plurality of semiconductor chips, wherein a functional surface of each semiconductor chip is provided with a bonding pad, a metal bump is formed on the surface of the bonding pad, the functional surface is also provided with a first plastic packaging layer, and the first plastic packaging layer covers the metal bump; bonding the first plastic packaging layers on the functional surfaces of the plurality of semiconductor chips on the carrier plate; and forming a second plastic packaging layer which coats the non-functional surface and the side wall surface of the semiconductor chip on the carrier plate. Because the first plastic package layer is generally formed by an injection molding or plastic transfer process, the formed first plastic package layer has a flat surface, so that the surface of each semiconductor chip has a flat surface, when the first plastic package layers on a plurality of discrete semiconductor chips are bonded with the carrier plate, each semiconductor chip and the carrier plate have high adhesive force, when the second plastic package layer covering a plurality of semiconductor chips is formed on the carrier plate, all the semiconductor chips cannot generate offset on the carrier plate when being impacted by the pressure of injection molding or plastic transfer, so that a pre-packaged panel is formed after the carrier plate is removed, when a rewiring layer connected with a pad is formed on the back surface of the pre-packaged panel, the connection position of the rewiring layer and the corresponding pad cannot generate offset, and the electrical connection performance between the rewiring layer and the pad is improved, thereby improving the stability and reliability of the package structure.
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. 1-19 are schematic structural diagrams illustrating a process of forming a package structure according to an embodiment of the invention.
Referring to fig. 1 to 6, a plurality of semiconductor chips 160 (refer to fig. 6) are provided, each semiconductor chip 160 includes a functional surface 11 and a non-functional surface 12 opposite to the functional surface 11, the functional surface 11 has a plurality of bonding pads 101 thereon, metal bumps 102 are formed on surfaces of the bonding pads 101, the functional surface 11 also has a first molding compound layer 103 thereon, and the first molding compound layer 103 covers the metal bumps 102.
The semiconductor chip 160 has a functional surface 11 and a non-functional surface 12 opposite to the functional surface 11, the functional surface is a surface on which an integrated circuit and a bonding pad are formed, the integrated circuit is formed in the semiconductor chip 160, a plurality of bonding pads 101 are formed on the functional surface of the semiconductor chip 160, the bonding pads 101 are electrically connected to the integrated circuit in the semiconductor chip 160, and the bonding pads 101 serve as ports for electrically connecting the integrated circuit in the semiconductor chip 160 to the outside. In one embodiment, the integrated circuit in the semiconductor chip 160 may include several semiconductor devices (such as transistors, memories, sensors, diodes and/or transistors, etc.) and interconnection structures (including metal wires and metal plugs) for connecting the semiconductor devices. The peripheral surface between the functional surface 11 and the non-functional surface 12 of the semiconductor chip 160 is a sidewall of the semiconductor chip 160.
The semiconductor chip 160 is formed by a semiconductor integrated manufacturing process, and a specific process of forming the semiconductor chip 160 is described in detail below with reference to fig. 1 to 6.
Firstly, referring to fig. 1 and fig. 2, fig. 2 is a schematic cross-sectional structure view along a cutting line AB in fig. 1, providing a wafer 100, where the wafer 100 includes a plurality of chip regions arranged in rows and columns and a dicing street region located between the chip regions; correspondingly forming a plurality of semiconductor chips 160 in a plurality of chip areas of the wafer 100; a plurality of pads 101 are formed on the functional surface of the semiconductor chip 160.
In one embodiment, the material of the wafer 100 may be single crystal silicon (Si), single crystal germanium (Ge), or silicon germanium (GeSi), silicon carbide (SiC); or silicon-on-insulator (SOI), germanium-on-insulator (GOI); or may be other materials such as group iii-v compounds such as gallium arsenide. The material of the bonding pad 101 may be one of aluminum, nickel, tin, tungsten, platinum, copper, and titanium.
Referring to fig. 3 and 4, fig. 4 is an enlarged schematic view of a metal bump formed on one pad in fig. 3, and a metal bump 102 is formed on a surface of the pad 101.
The metal bump 102 protrudes from the surface of the pad 101 and the functional surface, in an embodiment, the metal bump 102 is formed by one or more of aluminum, nickel, tin, tungsten, platinum, copper, titanium, chromium, tantalum, gold, and silver, which are used as materials of the metal bump 102 to raise the pad 101 for subsequent wiring, and the metal bump 102 also has the functions of protecting the pad and conducting heat.
In one embodiment, the process of forming the metal bump 102 includes: forming an insulating layer 150 on the functional surface 11 of the semiconductor chip 160, wherein the insulating layer 150 has a first opening exposing a part of the surface of the pad 101, the insulating layer 150 may be a single-layer or multi-layer stacked structure, and the material of the insulating layer 150 may be one or more of silicon nitride, silicon oxide, and resin material; forming an Under Bump Metal (UBM) on the surface of the insulating layer 150 and the sidewall and bottom surfaces of the first opening, the under bump metal being a single-layer or multi-layer stacked structure; forming a mask layer with a second opening on the convex lower metal layer, wherein the second opening at least exposes the surface of the convex lower metal layer in the first opening; forming a metal bump 102 in the second opening of the fox through an electroplating process; removing the mask layer; and etching to remove the under-bump metal layer on the surface of the insulating layer on both sides of the metal bump 102.
Referring to fig. 5, a first molding compound layer 103 is formed on the surface of the wafer 100 (the functional surface of the semiconductor chip 160), and the first molding compound layer 103 covers the metal bump 102.
The first plastic package layer 103 covers the top and the side wall surface of the metal bump 102, the first plastic package layer 103 has a flat surface, the forming process of the first plastic package layer 103 is an injection molding or transfer molding process, the first plastic package layer 103 is made of resin, and the resin may be one or more of epoxy resin, polyimide resin, benzocyclobutene resin, polybenzoxazole resin, polybutylene terephthalate, polycarbonate, polyethylene terephthalate, polyethylene, polypropylene, polyolefin, polyurethane, polyolefin, polyethersulfone, polyamide, polyurethane, ethylene-vinyl acetate copolymer, or polyvinyl alcohol.
Specifically, when the injection molding or transfer molding process is performed, the bottom of the wafer 100 is fixed in the mold, because the area of the bottom of the wafer is large, the wafer does not move in the mold of the injection molding or transfer molding device, so that the formed first plastic package layer 103 has a flat surface, after the wafer is cut, the formed plurality of discrete semiconductor chips 160 all have a flat surface, and the thicknesses of the plurality of semiconductor chips 160 can be kept consistent, and when the first plastic package layer 103 on the plurality of discrete semiconductor chips 160 is subsequently bonded with the carrier plate, because the first plastic package layer 103 has a flat surface, the adhesive force between each semiconductor chip 160 and the carrier plate is high, so that when the second plastic package layer covering the plurality of semiconductor chips 160 is subsequently formed on the carrier plate, when the second plastic package layer is impacted by the injection molding or transfer molding pressure, the positions of all the semiconductor chips 160 on the carrier plate do not shift, therefore, after the carrier plate is removed, the pre-sealing panel is formed, when the re-wiring layer connected with the bonding pad is formed on the back surface of the pre-sealing panel, the connection position of the re-wiring layer and the corresponding bonding pad cannot be shifted, the electrical connection performance between the re-wiring layer and the bonding pad is improved, and the stability and the reliability of the packaging structure are improved.
In addition, the formed first plastic package layer 103 is also used for fixing the metal bump 102, so as to prevent the metal bump 102 from being loosened or falling off from the pad 101 due to a transverse grinding force when the first plastic package layer and the second plastic package layer are subsequently planarized.
The formed first molding compound layer 103 may also be used to protect the metal bump 102, and prevent the metal bump 102 from being contaminated or damaged in a subsequent process.
In an embodiment, the size of the material particles in the first plastic package layer 103 is smaller than the size of the material particles in the second plastic package layer formed subsequently, so that the first plastic package layer 103 can better fill the gaps between and on both sides of the metal bumps 102, and the first plastic package layer 103 is in closer contact with the side surfaces of the metal bumps 102, so that the first plastic package layer 103 has a better fixing effect on the metal bumps 102, and when the first plastic package layer and the second plastic package layer are flattened by using a chemical mechanical polishing process to expose the top surfaces of the metal bumps 102, the metal bumps 102 can be better prevented from being loosened or falling off from the pads 101, and the metal bumps 102 can be prevented from being over-polished.
Referring to fig. 6, the wafer 100 (see fig. 5) is diced along the scribe line region to form a plurality of discrete semiconductor chips 160 having the first molding layer 103.
In another embodiment, referring to fig. 7, after forming the metal bump 102, before forming the first molding compound layer 103, an isolation sacrificial layer 120 is formed on the top surface or the top and sidewall surfaces of the metal bump 102; after the isolation sacrificial layer 120 is formed, a first molding layer 103 is formed to cover the isolation sacrificial layer 120 and the semiconductor chip 160.
It is found that if the first molding compound layer 103 is formed to directly cover the surface of the metal bump 102, and then after forming the second molding compound layer covering the non-functional surface and the sidewall surface of the semiconductor chip and peeling off the carrier board, it is necessary to remove a portion of the first molding compound layer and the second molding compound layer by planarization (chemical mechanical polishing process) to expose the top surface of the metal bump 102, during the planarization (chemical mechanical polishing process), the polishing force may cause a portion of the metal bump 102 to loosen or fall off from the pad 101. Therefore, in this embodiment, before forming the first plastic package layer 103, an isolation sacrificial layer 120 is formed on the top surface or the top and sidewall surfaces of the metal bump 102, and then a portion of the first plastic package layer 103 and the second plastic package layer may be removed by a process combining a chemical mechanical polishing process and an etching process to expose the metal bump, specifically, a portion of the first plastic package layer and the second plastic package layer is removed by the chemical mechanical polishing process to expose the isolation sacrificial layer surface, and then the isolation sacrificial layer on the top surface of the metal bump 102 is removed by the etching process to expose the top surface of the metal bump, so that not only the top surface of the metal bump is exposed, but also when a portion of the first plastic package layer and the second plastic package layer is removed by the chemical mechanical polishing process, the exposed surface is the isolation sacrificial layer, and a polishing pad in a polishing device may not contact with the metal bump, therefore, grinding force cannot be brought to the metal bump, so that the metal bump 102 is better prevented from loosening or falling off from the bonding pad 101, the precision of the connecting position between the subsequently formed rewiring layer and the corresponding metal bump is further improved, and the electrical connection performance between the rewiring layer and the metal bump 102 is further improved.
In addition, the formation of the isolation sacrificial layer 120 can also improve the adhesion between the first molding layer 103 and the metal bump 102.
In an embodiment, the isolation sacrificial layer 120 is made of silicon oxide, silicon nitride, or silicon oxynitride.
Referring to fig. 8, the wafer 100 (refer to fig. 7) is diced along the scribe line region to form a plurality of discrete semiconductor chips 160 having the isolation sacrificial layer 120 and the first molding compound 103.
Referring to fig. 9 or 11, a carrier plate 107 is provided; the first molding layer 103 on the functional surfaces of the semiconductor chips 160 is bonded to the carrier board 107.
The carrier plate 107 serves as a support platform for a subsequent process, the carrier plate 107 may be a glass carrier plate, a silicon carrier plate or a metal carrier plate, and the carrier plate 107 may also be a carrier plate made of other suitable materials.
The first molding compound 103 on the semiconductor chip 160 is adhered to the surface of the carrier 107 by an adhesive layer, and the functional surface (or the pad 101) of the semiconductor chip 160 faces the adhesive surface of the carrier 107.
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 semiconductor chips 160 are uniformly bonded to the carrier plate 107 in rows and columns.
Referring to fig. 10 or 11, a second molding layer 109 is formed on the carrier 107 to cover the non-functional surface and the sidewall surface of the semiconductor chip 160.
The second molding compound 109 is used to seal and fix the semiconductor chip 160 for forming a pre-packaged panel in the following. The second plastic package layer 109 also covers the surface of the carrier board 107 and the surface of the sidewall of the first plastic package layer 103.
The material of the second molding compound layer 109 may be one or more of epoxy resin, polyimide resin, benzocyclobutene resin, polybenzoxazole resin, polybutylene terephthalate, polycarbonate, polyethylene terephthalate, polyethylene, polypropylene, polyolefin, polyurethane, polyolefin, polyethersulfone, polyamide, polyurethane, ethylene-vinyl acetate copolymer, or polyvinyl alcohol.
The second molding layer 109 may be formed by injection molding (injection molding) or transfer molding (transfer molding) or other suitable processes.
When the second plastic package layer 109 is formed, the first plastic package layer 103 enables the surface of each semiconductor chip 160 to have a flat surface, when the first plastic package layers 103 on a plurality of discrete semiconductor chips 160 are bonded with the carrier board, because the first plastic package layers 103 have flat surfaces, the adhesion force between each semiconductor chip 160 and the carrier board is high, when the second plastic package layers 109 covering a plurality of semiconductor chips 160 are formed on the carrier board 107, when the second plastic package layers 109 covering the plurality of semiconductor chips 160 are impacted by the pressure of injection molding or transfer molding, the positions of all the semiconductor chips 160 on the carrier board cannot be shifted, so that a pre-packaged panel is formed after the carrier board 107 is removed, when a re-wiring layer connected with a pad is formed on the back of the pre-packaged panel, the connection position of the re-wiring layer and the corresponding pad cannot be shifted, and the electrical connection performance between the re-wiring layer and the pad is improved, thereby improving the stability and reliability of the package structure.
Referring to fig. 12 or 13, fig. 12 is performed on the basis of fig. 10, and fig. 13 is performed on the basis of fig. 11, the carrier board 107 (refer to fig. 10 or 11) is peeled off to form the pre-cover board 21, and the first molding compound layer 103 is exposed from the back surface of the pre-cover board 21.
The adhesive layer is removed by chemical etching, mechanical peeling, CMP, mechanical grinding, thermal baking, or the like, so that the carrier plate 107 is peeled off.
Referring to fig. 14 or with reference to fig. 15 and 16 in combination, fig. 14 is performed on the basis of fig. 12, fig. 15 is performed on the basis of fig. 14, and fig. 16 is performed on the basis of fig. 15, and a portion of the first molding layer 103 and the second molding layer 109 on the back surface of the pre-package panel 21 is removed to expose the top surface of the metal bump 102.
In an embodiment, when no isolation sacrificial layer is formed, a chemical mechanical polishing process is used to directly remove a portion of the first molding layer 103 and the second molding layer 109 on the back surface of the pre-sealing board 21, exposing the metal bump 102.
In another embodiment, when forming the isolation sacrificial layer 120, referring to fig. 15, a chemical mechanical polishing process is first used to remove a portion of the first molding compound layer 103 and the second molding compound layer 109, exposing the surface of the isolation sacrificial layer 120; referring to fig. 16, the isolation sacrificial layer 120 (refer to fig. 15) on the top surface of the metal bump 102 is removed by an etching process to expose the top surface of the metal bump 102, specifically, an opening 121 in the first molding compound layer 103 is formed at a position where the isolation sacrificial layer 120 is removed, and the opening 121 exposes the top surface of the metal bump 102. In this embodiment, by forming the isolation sacrificial layer 120, a chemical mechanical polishing process may be first used to remove a portion of the first plastic package layer and the second plastic package layer to expose a surface of the isolation sacrificial layer, and then an etching process is used to remove the isolation sacrificial layer on the top surface of the metal bump 102 to expose the top surface of the metal bump 102, so that the top surface of the metal bump can be exposed through the combination of the specific structure and the specific process, and since the exposed isolation sacrificial layer is the surface of the isolation sacrificial layer when the portion of the first plastic package layer and the second plastic package layer are removed by the chemical mechanical polishing process, a polishing pad in a polishing device does not contact with the metal bump, and thus does not bring a polishing force to the metal bump, thereby better preventing the metal bump 102 from loosening or falling off from the pad 101, and further improving the precision of a connection position between a subsequently formed rewiring layer and the corresponding metal bump, the electrical connection performance of the re-wiring layer and the metal bump 102 is further improved.
The etching process for removing the isolation sacrificial layer 120 is wet etching or dry etching. In an embodiment, when the isolation sacrificial layer 120 is made of silicon nitride, the isolation sacrificial layer 120 is removed by wet etching, and an etching solution used in the wet etching is a phosphoric acid solution.
Referring to fig. 17 and 18, an external contact structure connected to the metal bump 102 is formed on the back surface of the pre-cover plate 21.
The external contact structure includes a redistribution layer 110 on the back surface of the pre-packaged panel 21 and connected to the metal bumps 102, and an external contact 112 on the redistribution layer 110 and connected to the redistribution layer 110, and the metal bumps 102 on each semiconductor chip 160 are connected to the corresponding external contact structure. The external contact 112 is a solder ball, or the external contact 112 may also include a metal pillar and a solder ball on the surface of the metal pillar.
In a specific embodiment, the formation of the redistribution layer 110 and the external contacts 112 includes: after the carrier board is stripped, a rewiring layer 110 is formed on the back surface of the pre-sealing panel 21; forming an insulating layer 111 on the back surfaces of the rewiring layer 110 and the pre-sealing plate 21, wherein an opening for exposing part of the surface of the rewiring layer 110 is formed in the insulating layer 111, and the insulating layer 121 can be made of silicon nitride, borosilicate glass, phosphorosilicate glass or borophosphosilicate glass; external contacts 112 are formed in the openings.
Referring to fig. 19, after forming the external contact structure, further comprising: the pre-cover board is cut to form a plurality of discrete package structures 22.
It should be noted that the process of forming the external contact structure on the basis of fig. 16 is substantially the same as the process of forming the external contact structure in fig. 17-18, and is not described again here.
An embodiment of the present invention further provides a package structure, please refer to fig. 10 or fig. 11, including:
a carrier plate 107;
a plurality of semiconductor chips 160 adhered on the carrier board 107, each semiconductor chip 160 comprising a functional surface 11 and a non-functional surface 12 opposite to the functional surface 11, the functional surface 11 having a plurality of bonding pads 101, the bonding pads 101 having metal bumps 102 formed on the surface, the functional surface 11 further having a first molding compound layer 103, the first molding compound layer 103 covering the metal bumps 102, the first molding compound layer 103 on the functional surface of the semiconductor chip 160 adhered on the carrier board 107;
and a second molding compound layer 109 positioned on the carrier plate 107 and covering the non-functional surface and the sidewall surface of the semiconductor chip 160.
In one embodiment, the semiconductor chip 160 is formed by an integrated manufacturing process, including the steps of: providing a wafer, wherein a plurality of semiconductor chips are formed on the wafer, each semiconductor chip comprises a functional surface, and a bonding pad is arranged on each functional surface; forming a metal bump on the pad; forming a first plastic packaging layer covering the metal bump and the functional surface; and after the first plastic packaging layer is formed, cutting the wafer to form a plurality of discrete semiconductor chips.
In an embodiment, the material of the first molding layer 103 and the second molding layer 109 is resin, and the forming process of the first molding layer and the second molding layer is an injection molding or rotational molding process.
In one embodiment, the size of the material particles in the first molding layer 103 is smaller than the size of the material particles in the second molding layer 109.
In an embodiment, referring to fig. 11, an isolation sacrificial layer 120 is formed on a top surface or a top and a sidewall surface of the metal bump 102, and the first molding compound layer 103 further covers the isolation sacrificial layer 120.
The isolation sacrificial layer 120 is made of silicon oxide, silicon nitride or silicon oxynitride.
It should be noted that, in the present embodiment, for other limitations or descriptions of the package structure, please refer to corresponding limitations or descriptions of the formation process of the package structure, which are not repeated in the present embodiment.
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.
Claims (9)
1. A method for forming a package structure, comprising:
providing a plurality of semiconductor chips, wherein 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 bonding pads, the surface of each bonding pad is provided with a metal bump, the top surface or the top and side wall surfaces of each metal bump are provided with an isolation sacrificial layer, the functional surface is also provided with a first plastic package layer, the first plastic package layer covers the metal bumps and the isolation sacrificial layers, the first plastic package layer is provided with a flat surface, and the size of material particles in the first plastic package layer is smaller than that of material particles in a second plastic package layer formed subsequently;
providing a carrier plate;
bonding the first plastic packaging layers on the functional surfaces of the plurality of semiconductor chips on the carrier plate;
forming a second plastic packaging layer wrapping the non-functional surface and the side wall surface of the semiconductor chip on the carrier plate;
stripping the carrier plate to form a pre-packaged panel, wherein the first plastic packaging layer is exposed out of the back surface of the pre-packaged panel;
removing part of the first plastic packaging layer and the second plastic packaging layer on the back surface of the pre-packaged panel by adopting a chemical mechanical grinding process to expose the surface of the isolation sacrificial layer; the isolation sacrificial layer on the top surface of the metal bump is removed by adopting an etching process, and an opening exposing the metal bump is formed in the first plastic packaging layer, so that when the opening exposing the metal bump is formed in the first plastic packaging layer by removing part of the first plastic packaging material layer and removing the isolation sacrificial layer through the process of combining the chemical mechanical grinding process and the etching process, the metal bump can be better prevented from loosening or falling off from the bonding pad;
and forming an external contact structure connected with the metal bump on the back surface of the pre-cover plate.
2. The method for forming the package structure according to claim 1, wherein the semiconductor chip is formed by: providing a wafer, wherein a plurality of semiconductor chips are formed on the wafer, each semiconductor chip comprises a functional surface, and a bonding pad is arranged on each functional surface; forming a metal bump on the pad; forming a first plastic packaging layer covering the metal bump and the functional surface; and after the first plastic packaging layer is formed, cutting the wafer to form a plurality of discrete semiconductor chips.
3. The method for forming the package structure according to claim 2, wherein the material of the first molding compound layer and the second molding compound layer is resin, and the forming process of the first molding compound layer and the second molding compound layer is an injection molding or rotational molding process.
4. The method of claim 1, wherein a portion of the first molding compound and the second molding compound on the back surface of the pre-package panel is removed by a chemical mechanical polishing process to expose the top surface of the metal bump.
5. The method for forming the package structure according to claim 1, wherein the etching process is wet etching or dry etching.
6. The method for forming the package structure according to claim 1, wherein the isolation sacrificial layer is made of silicon oxide, silicon nitride or silicon oxynitride.
7. The method of claim 1, wherein the external contact structure includes a re-routing layer on the back surface of the pre-cover plate connected to the metal bump and an external contact on the re-routing layer connected to the re-routing layer.
8. The method of forming a package structure of claim 7, wherein the process of forming the re-routing layer and the external contacts comprises: after the carrier plate is stripped, forming a rewiring layer on the back surface of the pre-sealing panel; forming an insulating layer on the back surfaces of the rewiring layer and the pre-sealing surface plate, wherein an opening for exposing the surface of the rewiring layer part is formed in the insulating layer; an external contact is formed in the opening.
9. The method of forming the package structure of claim 1, further comprising, after forming the external contact structure: and cutting the pre-packaged panel to form a plurality of discrete packaging structures.
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| CN201910676061.2A CN110517959B (en) | 2019-07-25 | 2019-07-25 | Forming method of packaging structure |
| US17/629,040 US20220278075A1 (en) | 2019-07-24 | 2020-07-17 | Packaging structure and formation method thereof |
| PCT/CN2020/102767 WO2021013097A1 (en) | 2019-07-25 | 2020-07-17 | Packaging structure and formation method thereof |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102379036A (en) * | 2009-04-30 | 2012-03-14 | 瑞萨电子株式会社 | Semiconductor device and manufacturing method thereof |
| CN102856279A (en) * | 2011-06-28 | 2013-01-02 | 台湾积体电路制造股份有限公司 | Interconnect structure for wafer level package |
| CN107039362A (en) * | 2015-12-11 | 2017-08-11 | 瑞萨电子株式会社 | Semiconductor devices |
| CN107393894A (en) * | 2016-05-17 | 2017-11-24 | 台湾积体电路制造股份有限公司 | Integrate fan-out package |
| CN107887278A (en) * | 2016-09-30 | 2018-04-06 | 台湾积体电路制造股份有限公司 | The method for making semiconductor devices |
| CN108231606A (en) * | 2016-11-29 | 2018-06-29 | Pep创新私人有限公司 | Chip packaging method and encapsulating structure |
| CN109216323A (en) * | 2017-06-30 | 2019-01-15 | 台湾积体电路制造股份有限公司 | Semiconductor devices and the method for forming semiconductor devices |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07111962B2 (en) * | 1992-11-27 | 1995-11-29 | 日本電気株式会社 | Selective flattening polishing method |
| CN103745958B (en) * | 2013-12-05 | 2016-08-17 | 南通富士通微电子股份有限公司 | Encapsulating structure |
| CN103915355B (en) * | 2013-12-05 | 2017-01-25 | 通富微电子股份有限公司 | Package structure forming method |
-
2019
- 2019-07-25 CN CN201910676061.2A patent/CN110517959B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102379036A (en) * | 2009-04-30 | 2012-03-14 | 瑞萨电子株式会社 | Semiconductor device and manufacturing method thereof |
| CN102856279A (en) * | 2011-06-28 | 2013-01-02 | 台湾积体电路制造股份有限公司 | Interconnect structure for wafer level package |
| CN107039362A (en) * | 2015-12-11 | 2017-08-11 | 瑞萨电子株式会社 | Semiconductor devices |
| CN107393894A (en) * | 2016-05-17 | 2017-11-24 | 台湾积体电路制造股份有限公司 | Integrate fan-out package |
| CN107887278A (en) * | 2016-09-30 | 2018-04-06 | 台湾积体电路制造股份有限公司 | The method for making semiconductor devices |
| CN108231606A (en) * | 2016-11-29 | 2018-06-29 | Pep创新私人有限公司 | Chip packaging method and encapsulating structure |
| CN109216323A (en) * | 2017-06-30 | 2019-01-15 | 台湾积体电路制造股份有限公司 | Semiconductor devices and the method for forming semiconductor devices |
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