Detailed Description
The following is a more detailed description of the preferred embodiment of the invention, as illustrated in figures 1-1 through 9-3, from which the features and advantages of the invention will be apparent.
Referring to fig. 1-1, in one embodiment, a package carrier for carrying a package body is disclosed, the package carrier comprising:
A carrier sheet and a medium thinner than the carrier sheet, wherein a part of the carrier sheet belongs to a first area to which the medium is attached, and at least another part of the carrier sheet belongs to a second area to which a metal electrode is attached;
Wherein,
The bearing sheet can be peeled off relative to the packaging body and is repeatedly used for the packaging carrier plate;
The medium comprises any one of a release film, a transition coating or other medium which can form weak bonding force with the packaging body or the bearing sheet. Wherein figures 1-2 and 1-3 illustrate different situations of the medium, respectively.
For the technical scheme of the embodiment, because the medium is thinner than the bearing sheet, the medium is attached and the metal electrode is attached, when the medium comprises any one of a release film, a transition plating layer or other medium which can form weak binding force with the packaging body or the bearing sheet, the bearing sheet and the packaging body are provided with the strippable structural characteristics, and the packaging plate further has the technical effects of simple structure, improvement of packaging efficiency, reduction of cost and environmental protection. Furthermore, as the carrier sheet can be repeatedly used for packaging the carrier plate, the carrier sheet can be repeatedly utilized until indexes such as physical or electrical performance and the like of the carrier sheet no longer meet packaging requirements, and the whole cost of the technical scheme is greatly reduced.
It can be appreciated that the medium is thinner than the carrier sheet on the one hand, and needs to form a weak bonding force with the package or the carrier sheet on the other hand, so as to facilitate the peeling of the carrier sheet relative to the package, and specific examples are as follows:
(1) When the carrier is peeled off from the package, if the medium is of a type that can form weak binding force with the package, the medium will be in a separated state with the package along with the carrier, for example, the medium is the release film, which is bonded with the carrier in a liquid state and cured, and the binding force of the cured release film when bonded with other substances (such as the package) is in a weak binding force category, compared with the case that the cured release film has stronger binding force with the carrier, therefore, after the carrier is peeled off from the package, the release film can still be attached to the carrier, and the release film and the carrier can still be attached together. The release film may include a variety of different types of release films.
(2) When the carrier is peeled off from the package, if the medium is one that can form weak binding force with the carrier, the medium will be separated from the carrier along with the package, for example, the medium is the above-mentioned transition plating layer, because the binding force of the carrier and the transition plating layer is in the category of weak binding force due to the characteristics of the plating process, therefore, after the carrier is peeled off from the package, the transition plating layer can still be attached to the package, the transition plating layer and the package can still be attached together, and the transition plating layer is separated from the carrier. The transition plating layer may be formed by gold plating, silver plating, nickel plating, copper plating, or the like, and preferably, the transition plating layer is formed by copper plating.
(3) Naturally, when the medium is thinner than the carrier sheet and the medium belongs to other mediums capable of forming weak binding force with the package body or the carrier sheet, then the carrier sheet is also beneficial to stripping of the carrier sheet relative to the package body, or the medium and the carrier sheet can still be attached together after stripping, or the medium and the package body can still be attached together after stripping.
It will be appreciated that the carrier sheet is a base, and that the first region and the second region are both located above the carrier sheet, and that in theory both the first region and the second region may be used to carry the package. The carrier sheet shown in fig. 1-1 to 1-3 may be the one that is actively peeled off when the carrier sheet is peeled off relative to the package, and the package may be the one that is actively peeled off. The package includes various packages of integrated circuits. The first region and the second region are used for facilitating the formation of the electrode corresponding region and the non-electrode corresponding region in the packaging process.
In another embodiment, the height of the metal electrode, the thickness of the dielectric, may be designed according to the requirements of a particular package. In addition, according to different designs, the height of the metal electrode can be slightly higher/lower than the thickness of the medium, can be obviously higher/lower than the thickness of the medium, and can be flush.
In another embodiment, the metal electrode may comprise a plurality of electrode forms.
In another embodiment, if the side of the metal electrode contacting the carrier sheet is used as the bottom surface, the other side of the metal electrode opposite to the bottom surface, i.e. the surface of the metal electrode, may be further surface treated according to packaging requirements, such as gold plating, silver plating, tin plating, roughening, oxidation prevention, passivation treatment, cover protection layer, etc. More preferably, the surface of the metal electrode may be subjected to die bonding, wire bonding, welding, plastic packaging, and the like.
In a further embodiment of the present invention,
The metal electrode is realized by electroplating on the carrier sheet.
Although the above embodiment uses electroplating to form the electrodes, this does not mean that electroplating is only used, depending on whether other means are available in the process of technological development to form electrodes on the carrier sheet, such as a growth electrode or a spray electrode.
It can be appreciated that there is a case where when a release film is used as a medium, if the release film covers all areas of the carrier sheet in advance, the release film in the area to be plated can be removed first, the carrier sheet is exposed, and a metal electrode is formed by plating on the carrier sheet. Naturally, the thickness of the dielectric layer is determined according to the thickness of the plating layer required, but the insulating performance of electroplating is satisfied, and assuming that the plating layer required by the metal electrode is thicker, a layer of dry film or wet film photosensitive material can be covered on the release film, the area required to be electroplated is exposed in an exposure and development mode, and then the exposed area is electroplated on the carrier sheet, so that the metal electrode is formed. Similarly, there is a case where, when the transitional coating is used as a medium, if the transitional coating covers all areas of the carrier sheet in advance, the metal electrode can be formed by electroplating in such a manner that a layer of dry film type photosensitive material is coated on the transitional coating corresponding to the electroplated area, the exposure and development are performed, the transitional coating is removed by etching, the corresponding electroplated area on the carrier sheet is exposed, and then electroplating is performed on the exposed area on the carrier sheet, thereby forming the metal electrode.
Referring to fig. 2, in another embodiment,
An insulating layer is attached to the first region. It will be appreciated that the insulating layer is required for the encapsulation process that is common in encapsulation processes, but not all encapsulation processes are required. Similar to the foregoing, the present embodiment aims to emphasize that in the scenario where an insulating layer is required, the insulating layer is subordinate to the package body after the carrier sheet is peeled off with respect to the package body.
More preferably, at least a portion of the insulating layer is attached to the metal electrode. Obviously, when the insulating layer is provided, the package carrier can realize a multi-layer design, and more specific examples are described later. In view of the foregoing description of other embodiments, it can be appreciated that the present disclosure may use the package carrier with peel characteristics for the multi-layer process of the package body, and still provide the carrier with peel-facilitating characteristics.
In a further embodiment of the present invention,
When the bearing sheet is peeled off relative to the packaging body, the metal electrode is subordinate to the packaging body.
In this embodiment, the package carrier according to this embodiment may be used to make the metal electrode still integrated with the package body after the peeling, that is, the metal electrode may still be connected to and attached to the package body. This illustrates the excellent effect of the present embodiment that the releasable carrier sheet can improve packaging efficiency and reduce cost.
In a further embodiment of the present invention,
The metal electrode comprises a first attachment, and the first attachment is subordinate to the packaging body after the bearing sheet is peeled off relative to the packaging body.
It can be appreciated that the first attachment on the metal electrode may be any reasonable attachment on the metal electrode in the packaging process of the integrated circuit, including various attachment possibilities such as glue, film, insulating layer, bonding wire, IC, etc. As in the previous embodiment, this embodiment is intended to emphasize that the relevant attachment can still be attached to the package after the carrier sheet has been peeled off.
In another embodiment, the carrier sheet is in the form of a belt. It will be appreciated that the shape of the carrier sheet may be any shape that is convenient for production, with the strip being advantageous for pipelining. Preferably, in another embodiment, the longitudinal direction of the carrier sheet is in a closed loop mode.
It will be appreciated that the carrier sheet is generally rectangular in shape, extending in a transverse direction, and has two sides, a length and a width, the long direction referring to the location of the long side. When the long direction of the carrier sheet is in a closed loop mode, the continuous production is facilitated, and the efficiency of subsequent packaging is greatly improved.
In a further embodiment of the present invention,
The bearing sheet comprises any one of stainless steel with lower thermal expansion coefficient or other metals with thermal expansion coefficient matched with plastic packaging resin.
It can be appreciated that in this embodiment, the carrier sheet is selected. For this embodiment, the carrier sheet is profiled by its coefficient of thermal expansion in order to overcome the negative effects of thermal expansion in the packaging process. It should be noted that, according to the foregoing embodiments, the basic scheme and the principle of the disclosure are described, and with the development of technology, the disclosure does not exclude nonmetallic materials as carrier sheets.
In another embodiment, the insulating layer is attached to the package after the carrier is peeled off from the package. As with this embodiment, the present embodiment is intended to emphasize that the insulating layer can still be attached, subordinate to the package after the carrier sheet is peeled off. This means that the package carrier disclosed in the present disclosure can be used in a packaging process of a package body containing an insulating layer.
More preferably, the insulating layer includes a second attachment, and the second attachment is attached to the package after the carrier is peeled off relative to the package. It can be appreciated that the second attachment on the insulating layer may be any reasonable attachment on the insulating layer in the packaging process of the integrated circuit, including various attachment possibilities such as glue, film, electrode, bonding wire, IC, etc. As in the previous embodiments, this embodiment is intended to emphasize that the relevant attachment can still be attached to the package after the carrier sheet is peeled off.
Referring to fig. 3, in another embodiment, a conductive paste may be further attached to the insulating layer to meet the needs of some packaging processes.
More preferably, the conductive paste may be a platable conductive paste.
Referring to fig. 4-1, in another embodiment, in the packaging process without the insulating layer, the metal electrode and the release film are attached to the carrier sheet, and the glue is sequentially attached to the metal electrode and the release film (corresponding to the first region and the second region) and the substrate is further attached to the glue.
Referring to fig. 4-2 and 4-3, it is shown that in the packaging process with an insulating layer, the conductive paste is further attached on the insulating layer, and in the case that the conductive paste is preferably an electroplateable conductive paste, a metal electrode and a release film are attached on the carrier sheet, and the insulating layer, the electroplateable conductive paste, a glue and a substrate are further attached on the glue are sequentially attached on the metal electrode and the release film (the first region and the second region corresponding thereto).
It can be seen that in the cases shown in fig. 4-2, 4-3, the conductive paste or the electroplate conductive paste not only covers the insulating layer, but also can bridge between the metal electrodes. The three metal electrodes shown in fig. 4-2 may be named as a first metal electrode, a second metal electrode, and a third metal electrode from left to right, respectively, and it is apparent that the conductive paste bridges between the first metal electrode and the third metal electrode.
With respect to the two embodiments illustrated in figures 4-2, 4-3 and the text of the drawings herein, it should be noted that an insulating layer may be used for electrically insulating isolation, and that the conductive paste on top of the insulating layer provides electrical communication across the ends of the insulating layer due to bridging between the different metal electrodes. At this time, the package carrier is obviously beneficial to realizing the package of the double-sided circuit.
In another embodiment, to meet certain packaging needs, the conductive paste and the metal electrode may be further pattern plated, i.e., the surfaces of the conductive paste and the metal electrode are patterned. It will be appreciated that the metal layer resulting from the pattern plating may be in electrical communication with the bottom of the metal electrode (i.e., the portion of the metal electrode in contact with the carrier sheet, which may be referred to as the bottom electrode), as desired for packaging, or with other electrodes that need to be in communication, as desired for packaging. Preferably, in other embodiments, the patterned relevant surface can be further subjected to metal thickening, surface treatment, etching and the like according to packaging requirements.
For the above embodiments, further pattern plating may improve the conductivity and surface properties of the crossover region, reduce the resistivity, improve the conductive surface, which is particularly important in high frequency applications, especially when the skin effect is significant.
In a further embodiment of the present invention,
And the release film comprises a third attachment, and the third attachment is subordinate to the packaging body after the bearing sheet is peeled off relative to the packaging body. It can be understood that the third attachment on the release film may be any reasonable attachment on the release film in the packaging process of the integrated circuit, including various attachment possibilities such as a photosensitive film, a dry film, an insulating film, a glue, an electrode, a bonding wire, an IC, and the like. As in the previous embodiments, this embodiment is intended to emphasize that the relevant attachment can still be attached to the package after the carrier sheet is peeled off.
In another embodiment, when the release film comprises a photosensitive film, a dry film, an insulating film or other films, the films on the release film can be further processed by exposure, development or laser burning, so that one part of the area of the carrier sheet belongs to a first area where the release film is attached, and at least one other part of the area of the carrier sheet belongs to a second area where the metal electrode is attached, preferably, the metal electrode in the second area is formed by electroplating as described above.
Further, in another embodiment, the above films on the release film may be further processed as follows:
firstly, removing the photosensitive film, the dry film or the insulating film;
secondly, coating an insulating coating on the release film;
thirdly, carrying out metallization treatment on the insulating coating to obtain a metal layer on the release film;
Thirdly, enabling the metal layer on the release film to be communicated with a bottom electrode, wherein the bottom electrode refers to a part of the metal electrode, which is contacted with the bearing sheet;
Thirdly, patterning the metal layer on the release film, thickening, surface treating and etching the metal of the metal layer on the release film;
and performing packaging processes such as die bonding, wire bonding, welding, plastic packaging and the like on the metal layer on the release film.
It can be appreciated that the above embodiments are examples of further processing of release films on package carrier plates according to the present disclosure.
In another embodiment, fig. 5-1 illustrates the case where the third attachment on the release film is a dry film and the metal electrode belongs to a conventional electrode, and illustrates the case of 3 metal electrodes.
In another embodiment, fig. 5-2 illustrates a case where the third attachment on the release film is a resin and the metal electrodes belong to a special-shaped electrode, and illustrates a case where 2 metal electrodes each including a portion of the bottom electrode and the remaining columnar metal pillar portion other than the bottom electrode described in the foregoing plural.
In another embodiment, fig. 5-3 illustrate a case where the third attachment on the release film is a dry film and the metal electrodes belong to a special-shaped electrode, and illustrate a case of 2 metal electrodes, wherein each metal electrode includes a portion of the bottom electrode and the remaining cylindrical metal pillar portion other than the bottom electrode.
In another embodiment, fig. 5-4 illustrate a case where the third attachment on the release film includes a dry film over the resin and a chip base over the dry film, and the metal electrodes belong to the special-shaped electrode, and illustrate a case where 2 metal electrodes, each of which includes a portion of the bottom electrode, a portion of the top electrode that is flush with the chip base, and the remaining columnar metal pillar portion between the bottom electrode and the top electrode, and the chip base is located between the top electrodes of the 2 metal electrodes, and between the chip base and each of the top electrodes is the dry film over the resin.
In another embodiment, fig. 6 illustrates a case where the package carrier of the present disclosure is used for chip packaging. The third attachment on the release film comprises resin and plastic packaging resin attached to the resin, the plastic packaging resin is used for packaging the chip on the chip base, and the plastic packaging resin is attached to the 2 metal electrodes, wherein each metal electrode comprises a bottom electrode and a top electrode. In addition, bonding wires are connected between the chip and the 2 top electrodes.
In addition, in fig. 6, the chip base and the top electrode have two ends in a transverse direction, wherein the plastic package resin is included between one end of the chip base and one end of the top electrode opposite to the one end of the chip base. And, each end of the chip base and the top electrode includes upper and lower protruding portions and a recess portion between the upper and lower protruding portions, it can be understood that this is for better bonding with the molding resin.
The above more schematic diagrams and embodiments describe in detail how the package carrier of the present disclosure can be used in related application scenarios in the field when the medium is a release film. When the carrier sheet is peeled off, the release film tends to follow the carrier sheet.
In the following, it is described by other embodiments and schematic diagrams how the package carrier according to the present disclosure is used in related application scenarios in the field when the medium is a transitional plating layer. When the carrier sheet is peeled off, the transitional coating tends to follow the package.
In another embodiment, fig. 7-1 illustrates the case where the deposit on the transitional coating is a dry film and the metal electrodes belong to the conventional electrode, and illustrates the case of 3 metal electrodes.
In another embodiment, fig. 7-2 illustrates the case where the deposit on the transitional coating is a resin and the metal electrodes belong to a conventional electrode, and illustrates the case of 3 metal electrodes. In contrast, in another embodiment, fig. 7-3 illustrate the case of a shaped electrode, such as a T-shaped electrode, and illustrate the case of 3 metal electrodes.
In another embodiment, FIG. 8-1 illustrates the carrier sheet of FIG. 7-3 after peeling, FIG. 8-2 further illustrates the carrier sheet after removal of the transitional coating, FIG. 8-3 illustrates the package of the chip with bonding wires in another embodiment, and FIG. 8-4 illustrates the package of the chip with plastic resin in another embodiment.
In another embodiment, fig. 9-1 illustrates a case where the attachments on the transitional coating are resin, the metal electrodes belong to special-shaped electrodes, and the chip package is completed by using plastic package resin, wherein each metal electrode not only comprises a T-shaped electrode, but also comprises a part of the bottom electrode and the rest of the cylindrical metal pillar parts except the bottom electrode. In another embodiment, fig. 9-2 illustrates the package after the carrier sheet is peeled off, and the transitional coating remains attached to the package. Fig. 9-3 illustrates the package after further removal of the overplate in another embodiment.
From the foregoing fig. 7-3 to 8-4, it can be appreciated that the disclosure may first peel the carrier sheet and remove the transitional coating, then package the chip and bond the wire, or, like fig. 9-1 to 9-3, the disclosure may also continue to package the chip and bond the wire without peeling the carrier sheet, and finally peel the carrier sheet and remove the transitional coating. In fact, for the embodiments of the release film described above, the carrier sheet and the release film can be peeled off first, and the packaging can be completed before the carrier sheet and the release film are peeled off. This is advantageous for the division of industry, which means that the carrier sheet can be peeled off by the supply chain manufacturer and then provided to the customer, or the carrier sheet can be peeled off by the customer and delivered directly to the customer along with the mixed product of the carrier sheet and the carrier sheet.
For the above embodiments, under the existing process capability (mainly referred to as line width and line spacing), even if two layers of different attachments are still unable to achieve the electrical communication relationship between the different electrodes, then adding a layer of attachment to achieve the electrical communication between the different electrodes may be considered. That is, theoretically, each of the attachments described above may be two to N layers, where N is a positive integer. Thus, the package carrier of the present disclosure may be used for an RGB LED package carrier, and may also be used for a BGA-like IC package carrier, and the like. In addition, it should be noted that, as described above, the insulating layer may be used to realize a multi-layer design, and if a reasonable design is performed, the bottom and the upper portion of the insulating layer may be designed as electrode layers, and each electrode layer may be realized by electroplating. That is, the insulating layer of the present disclosure, each attachment, may have a multi-layered structure, and may be used to provide electrical communication between different electrodes. Similarly, the attachment on the metal electrode may have a multi-layer structure, and further, the metal electrode and the insulating layer may overlap and be spaced apart to form a multi-layer structure, such as an insulating layer having a metal electrode thereon and an insulating layer thereon, or a metal electrode having an insulating layer thereon and a metal electrode thereon, and so on.
It should be noted that, in the foregoing embodiments, when the carrier sheet is peeled off from the metal electrode or the insulating layer or the attachment or a specific package, the metal electrode or the insulating layer or the attachment or the specific package may be transferred to the transfer by using a transfer material having an adhesive property, and the bonding and the transfer may be achieved by, for example, (1) using a pressure-sensitive adhesive having a sufficient viscosity, (2) using a UV reducing adhesive having a sufficient viscosity, irradiating UV light when the transfer is completed, reducing the viscosity of the UV adhesive, (3) using a hot melt adhesive to heat the transfer, and after the transfer is completed, the hot melt adhesive is not adhered at room temperature, and (4) using a thermosetting hot melt adhesive to adhere the transfer, and after the transfer is completed, heating and curing the hot melt adhesive.
The thickness of each electrode layer and the like can be effectively controlled by the method, so that compared with the prior art, metals required by electroplating are greatly saved, and particularly, the method has a high-frequency application scene. In addition, the bearing sheet disclosed by the invention does not need a thicker copper layer for supporting, and metal is also obviously saved.
The foregoing description of the preferred embodiments of the present disclosure is not intended to limit the disclosure, and common variations and substitutions within the scope of the technical solutions of the present disclosure should be included in the scope of the present disclosure.