阅读说明：本技术 一种支撑框架及其制造方法 (Support frame and manufacturing method thereof ) 是由 陈先明 冯磊 黄本霞 王闻师 李敏雄 辛世贵 于 2020-10-27 设计创作，主要内容包括：本公开提供一种支撑框架和支撑框架的制造方法,所述方法包括以下步骤：A)准备临时承载板；B)在所述临时承载板上形成线路层；C)在所述线路层上形成直立的金属导电柱和牺牲金属桩；D)用介质材料层压所述金属导电柱和所述牺牲金属桩形成介质层；E)减薄和平坦化所述介质层,暴露出所述金属导电柱和所述牺牲金属桩的端面；F)去除所述临时承载板；G)蚀刻掉所述牺牲金属桩以在所述介质层中形成嵌埋空腔。(The present disclosure provides a support frame and a method of manufacturing a support frame, the method comprising the steps of: A) preparing a temporary bearing plate; B) forming a circuit layer on the temporary bearing plate; C) forming an upright metal conductive column and a sacrificial metal column on the circuit layer; D) laminating the metal conductive column and the sacrificial metal pile by using a medium material to form a medium layer; E) thinning and flattening the dielectric layer to expose the end surfaces of the metal conductive posts and the sacrificial metal posts; F) removing the temporary bearing plate; G) the sacrificial metal posts are etched away to form embedded cavities in the dielectric layer.)

1. A method of manufacturing a support frame, comprising the steps of:

A) preparing a temporary bearing plate;

B) forming a circuit layer on the temporary bearing plate;

C) forming an upright metal conductive column and a sacrificial metal column on the circuit layer;

D) laminating the metal conductive column and the sacrificial metal pile by using a medium material to form a medium layer;

E) thinning and flattening the dielectric layer to expose the end surfaces of the metal conductive posts and the sacrificial metal posts;

F) removing the temporary bearing plate;

G) the sacrificial metal posts are etched away to form embedded cavities in the dielectric layer.

2. The manufacturing method according to claim 1, wherein the step B includes:

applying a seed layer on the temporary carrier plate;

applying a metal layer on the seed layer;

applying a first photoresist layer on the metal layer;

patterning the first photoresist layer to form a pattern exposing the metal layer;

etching the metal layer and the seed layer under the pattern to form the line layer;

and removing the first photoresist layer.

3. The manufacturing method according to claim 1, wherein the step B includes:

applying a first photoresist layer on the bearing plate;

patterning the first photoresist layer to form a circuit pattern corresponding to the circuit layer;

electroplating metal in the circuit pattern to form the circuit layer;

and removing the first photoresist layer.

4. The manufacturing method according to claim 1, wherein the step a further comprises depositing a metal protection layer on the temporary carrier plate.

5. The manufacturing method according to claim 4, wherein the metal protective layer includes nickel.

6. The method of manufacturing according to claim 4, wherein the step F further comprises removing the metal protective layer by etching.

7. The manufacturing method according to claim 1, wherein the step C includes:

applying a second photoresist layer on the line layer;

patterning the second photoresist layer to form a through hole pattern;

electroplating and depositing metal in the through hole pattern to form the metal conductive column and the sacrificial metal pile;

and removing the second photoresist layer.

8. The manufacturing method according to claim 1, wherein the step G includes:

applying a third photoresist layer on the upper surface and the lower surface of the dielectric layer;

patterning the third photoresist layer to form an opening region exposing the sacrificial metal post;

etching the sacrificial metal posts;

removing the dielectric material surrounded by the sacrificial metal posts through the open areas;

and removing the third photoresist layer.

9. A method of manufacture as claimed in claim 1, wherein the dielectric material comprises a glass fibre reinforced polymer.

10. The method of manufacturing according to claim 9, wherein the polymer is selected from the group consisting of polyimide, epoxy, bismaleimide/triazine, polyphenylene oxide, polyacrylate, prepreg, and blends thereof.

11. The method of manufacturing of claim 1, wherein the wiring layer, metal via post, and sacrificial metal post are formed of copper.

12. A supporting frame comprises a dielectric layer, an embedded cavity penetrating through the dielectric layer and a metal conductive column extending along the thickness direction of the dielectric layer, and is characterized in that a circuit layer is formed on one surface of the dielectric layer, wherein the circuit layer is surrounded by the dielectric layer, the exposed surface of the circuit layer is flush with the surface of the dielectric layer, and the metal conductive column is electrically connected with the circuit layer.

Technical Field

The embodiment of the application relates to the technical field of semiconductor device packaging, in particular to a supporting frame and a manufacturing method thereof.

Background

With the drive for ever greater demands for miniaturization of increasingly complex electronic devices, consumer electronic components such as computers and telecommunications equipment are becoming more and more integrated. The packaging method for realizing the embedded chip by utilizing the supporting frame is greatly developed and applied in actual production, and the requirements of miniaturization, lightness, thinness and high integration of the size of the electronic device in the market are met.

The embedding method has many advantages, and the cost of the first level package such as wire bonding, flip chip or SMD (surface mount device) bonding is reduced. Since the chip and the substrate are seamlessly connected in a single product, electrical properties are improved. Packaged chips become thinner, resulting in a better form factor, and the upper surface of the embedded chip package is vacated for other uses, including further space saving configurations, such as uses using stacked chips and PoP (package on package) technology. At present, the panel-level embedding technology for embedding and packaging the chip through the supporting frame becomes an advanced production process, and can provide diversified packaging requirements for customers.

In the prior art, a method for manufacturing an embedded supporting frame is provided, and the embedded supporting frame mainly includes the following steps: a) obtaining a sacrificial carrier, and applying a copper seed layer on the sacrificial carrier; b) applying a dry film photoresist on a carrier; c) patterning the dry film and forming a through hole; d) depositing copper in the through hole to form a copper through hole column; e) laminating the via copper pillars with a polymer dielectric; f) thinning and planarizing the dielectric layer to expose ends of the copper pillars; g) the sacrificial carrier and seed layer are removed.

When the method is used for manufacturing the embedded supporting frame, all the through holes can be manufactured simultaneously, so that the through hole column is higher in production efficiency, and the through hole column can be designed to have any shape according to different requirements. However, the manufacturing method of the embedded support frame also has many defects: 1) only the conducting columns can be arranged, and the structure is single; 2) after the dielectric layer containing the glass fiber reinforced material is thinned and flattened, glass fiber exposure is easily caused, and the glass fiber exposure can cause the problems of copper migration, poor green oil binding force, short circuit and the like; 3) when a support frame having a small thickness is manufactured, the frame has poor thickness uniformity and is not rigid enough to be folded easily.

Disclosure of Invention

In view of the above, an objective of the embodiments of the present invention is to provide a supporting frame and a manufacturing method thereof, so as to solve the above technical problems in the prior art.

In view of the above object, in a first aspect, embodiments of the present application provide a method of manufacturing a support frame, the method comprising the steps of:

A) preparing a temporary bearing plate;

B) forming a circuit layer on the temporary bearing plate;

C) forming an upright metal conductive column and a sacrificial metal column on the circuit layer;

D) laminating the metal conductive column and the sacrificial metal pile by using a medium material to form a medium layer;

E) thinning and flattening the dielectric layer to expose the end surfaces of the metal conductive posts and the sacrificial metal posts;

F) removing the temporary bearing plate;

G) the sacrificial metal posts are etched away to form embedded cavities in the dielectric layer.

In some embodiments, step B comprises:

applying a seed layer on the temporary carrier plate;

applying a metal layer on the seed layer;

applying a first photoresist layer on the metal layer;

patterning the first photoresist layer to form a pattern exposing the metal layer;

etching the metal layer and the seed layer under the pattern to form the line layer;

and removing the first photoresist layer.

In other embodiments, step B comprises:

applying a first photoresist layer on the bearing plate;

patterning the first photoresist layer to form a circuit pattern corresponding to the circuit layer;

electroplating metal in the circuit pattern to form the circuit layer;

and removing the first photoresist layer.

In some embodiments, step a further comprises depositing a metal protection layer on the temporary carrier plate, preferably the metal protection layer comprises nickel.

In some embodiments, step F further comprises removing the metal protection layer by etching.

In some embodiments, step C comprises:

applying a second photoresist layer on the line layer;

patterning the second photoresist layer to form a through hole pattern;

electroplating and depositing metal in the through hole pattern to form the metal conductive column and the sacrificial metal pile;

and removing the second photoresist layer.

In some embodiments, step G comprises:

applying a third photoresist layer on the upper surface and the lower surface of the dielectric layer;

patterning the third photoresist layer to form an opening region exposing the sacrificial metal post;

etching the sacrificial metal posts;

removing the dielectric material surrounded by the sacrificial metal posts through the open areas;

and removing the third photoresist layer.

In some embodiments, the media material comprises a glass fiber reinforced polymer, preferably selected from the group consisting of polyimides, epoxy resins, bismaleimide/triazine resins, polyphenylene oxides, polyacrylates, prepregs, and blends thereof.

Preferably, the line layer, the metal via post and the sacrificial metal post in the embodiment of the present invention are all formed of copper.

In a second aspect, an embodiment of the present application provides a support frame, which includes a dielectric layer, an embedded cavity penetrating through the dielectric layer, and a metal conductive pillar extending along a thickness direction of the dielectric layer, wherein a circuit layer is formed on one side of the dielectric layer, the circuit layer is surrounded by the dielectric layer, an exposed surface of the circuit layer is flush with a surface of the dielectric layer, and the metal conductive pillar is electrically connected to the circuit layer.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only the embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIGS. 1a-1f are schematic intermediate structural views illustrating a method for manufacturing a support frame according to an embodiment of the present disclosure;

fig. 2 is a cross-sectional view of a support frame according to an embodiment of the present application.

Description of reference numerals:

100-supporting frame, 1-dielectric layer, 2-circuit layer, 3-metal conductive column, 4-embedded cavity, 5-first photoresist layer, 6-temporary bearing plate, 7-sacrificial metal pile, 8-second photoresist layer, 9-dielectric material, 10-third photoresist layer and 11-opening region.

Detailed Description

In order to make the objects, features and advantages of the embodiments of the present application more comprehensible, embodiments of the present application are described in detail below with reference to the accompanying drawings. It is clear that the described embodiments are only a part of the examples of the present application, and not all examples. All other embodiments that can be derived by a person skilled in the art from the embodiments given herein without making any creative effort shall fall within the protection scope of the present application.

Fig. 1a to 1f are schematic intermediate structural views illustrating a method for manufacturing a support frame according to an embodiment of the present disclosure. As shown in fig. 1, the method of manufacturing the support frame includes the following steps.

As shown in fig. 1a, a temporary carrier plate 6 is prepared (step a), and the temporary carrier plate 6 serves as a temporary support during the manufacturing of the support frame and is removed after the manufacturing of the support frame is completed. The shape of the temporary support plate 6 is not limited in this embodiment. The temporary carrier plate 6 may be any metal plate or glass substrate with a separation layer applied on the surface, such as a copper plate, an aluminum plate, a stainless steel plate, or an aluminum alloy plate, and may also be a sacrificial copper foil or a surface copper clad plate. Preferably, the temporary carrier plate 6 in this embodiment is a double-layer copper-clad plate with double-layer copper foils respectively covered on both sides of the insulating layer, and the double-layer copper foils are physically pressed together, so that the two layers are easy to separate and can be added on both sides simultaneously.

Next, as shown in fig. 1B, forming a circuit layer 2 on the temporary carrier 6 (step B); the wiring layer 2 is typically formed by means of pattern transfer.

In one embodiment, the step B includes applying a seed layer on the temporary carrier plate, applying a metal layer on the seed layer, applying a first photoresist layer 5, such as a photosensitive dry film, on the metal layer, patterning the first photoresist layer 5 to form a pattern exposing the metal layer, and etching the seed layer and the metal layer under the pattern to form the circuit layer 2.

The seed layer may comprise titanium, copper, titanium copper or titanium tungsten alloy, etc., and the seed layer may be formed by deposition, chemical plating or sputtering. In this embodiment, a copper seed layer is deposited and the metal layer is a copper layer.

The first photoresist layer 5 may be a negative photoresist dry film, the exposed portion of the negative photoresist dry film may form a cross-linked polymer, and after development, the unexposed dry film may be removed by an alkaline solution to form a pattern exposing the metal layer.

The first photoresist layer 5 may be removed after the circuit layer 2 is fabricated, or may be removed together with other photoresist layers in a subsequent process. For example, the first photoresist layer 5 may be removed along with the second photoresist layer 8 (see description below) in a subsequent process.

As an alternative, since the copper foil on the circuit layer 2 needs to be etched and removed after the temporary carrier board is removed, in order to protect the circuit layer 2 from etching, a metal protection layer is formed on the temporary carrier board before step B. Accordingly, after removing the temporary carrier 6 and etching the copper foil, the metal protection layer is etched away.

The metal cap layer typically comprises nickel and may also comprise, for example, copper, tungsten, titanium tungsten alloys, tin, lead, tin-lead alloys, and the like, so long as removal of the metal cap layer does not affect the metal being protected. The metal protective layer may typically be removed using suitable solvent or plasma etching conditions.

In another embodiment of forming the circuit layer 2, the step B includes applying a seed layer on the temporary carrier, applying a first photoresist layer 5 on the seed layer, patterning the first photoresist layer 5, such as a photosensitive dry film, to form a circuit pattern corresponding to the circuit layer 2, and electroplating and depositing a metal in the circuit pattern to form the circuit layer 2. Other conditions of this embodiment are the same as those of the previous embodiment.

Then, as shown in fig. 1C, a metal conductive pillar 3 and a sacrificial metal post 7 are formed on the line layer 2 (step C). The metal conductive column 3 is a conductive metal column, such as a copper column, an aluminum column, a gold column, a silver column, and the like, preferably a copper column. The shape of the metal conductive pillar 3 is not limited in this embodiment.

The sacrificial metal posts 7 are intended to penetrate the embedded cavity 4 of the support frame, and a plurality of sacrificial metal posts 7, preferably copper posts, may be provided around predetermined positions of the embedded cavity 4.

Step C includes applying a second photoresist layer 8, such as a photosensitive dry film, on the circuit layer 2, patterning the second photoresist layer 8 by exposure and development to form conductive through holes and sacrificial through holes at predetermined positions, where the conductive through holes and the sacrificial through holes correspond to the metal conductive pillars 3 and the sacrificial metal posts 7 in the same number and positions, and then depositing metal, such as copper, in the conductive through holes and the sacrificial through holes by electroplating or other processes, so as to form the metal conductive pillars 3 and the sacrificial metal posts 7, and after the metal conductive pillars 3 and the sacrificial metal posts 7 are manufactured, the second photoresist layer 8 and the first photoresist layer 5 may be removed together.

Next, as shown in fig. 1D, a dielectric material 9 is laminated or coated on the temporary carrier plate to form a dielectric layer 1 covering the metal conductive posts 3 and the sacrificial metal posts 7 (step D). Here, covering the metal conductive pillar 3 and the sacrificial metal pile 7 means that the dielectric material 9 surrounds the metal conductive pillar 3 and the sacrificial metal pile 7, submerges the top of the metal conductive pillar 3 and the sacrificial metal pile 7 away from the circuit layer 2, and completely fills the gap between the metal conductive pillar 3 and the sacrificial metal pile 7.

The dielectric material 9 may be a glass fiber reinforced polymer, preferably selected from the group consisting of polyimide, epoxy, bismaleimide/triazine resin (BT resin), polyphenylene oxide, polyacrylate, prepreg, and blends thereof. In a preferred embodiment, the dielectric material 9 is a prepreg (PP).

After the dielectric layer 1 has cured, the dielectric layer 1 is thinned and planarized at the side remote from the line layer 2, as shown in fig. 1E (step E). By thinning and planarizing the dielectric layer 1, the ends of the metal conductive posts 3 and the sacrificial metal posts 7 away from the circuit layer 2 are exposed and are flush with the surface of the dielectric layer 1, that is, flush with the surface of the dielectric layer 1. Thinning and planarizing the dielectric layer 1 may be accomplished using plasma etching, lapping, chemical and/or mechanical polishing, and the like. The dielectric layer 1 has a first surface on one side of the temporary loading plate and a second surface opposite to the first surface far away from the temporary loading plate, and the first surface and the second surface can be parallel.

After the thinning and planarization are completed, the temporary carrier plate 6 is removed (step F), the double-layered copper foil is separated, for example, by mechanical force, and then the copper foil is etched away. In an embodiment with a metal protection layer, the metal protection layer on the first surface is removed by etching.

Next, as shown in fig. 1f, the sacrificial metal posts 7 are etched away to form embedded cavities 4 in the dielectric layer 1 (step G). Step G may include applying a third photoresist layer 10, such as a photosensitive dry film, on the upper and lower surfaces (the first and second surfaces) of the dielectric layer 1, respectively, forming an open region 11 on the third photoresist layer 10 by exposure and development to expose the sacrificial metal post 7, then etching the sacrificial metal post 7 in the open region 11, and removing the dielectric material 9 surrounded by the sacrificial metal post 7 through the open region 11 to form the embedded cavity 4, and finally removing the third photoresist layer 10.

The embedded cavity 4 penetrates through the dielectric layer 1 along the thickness direction of the dielectric layer 1. The embedded cavity 4 may be formed with a cross section of different shapes, such as rectangular, circular, irregular, etc., according to design requirements, and the embodiment is not limited.

The embedded cavity 4 is used to embed electronic components, for example active devices such as chips, but also passive devices such as resistors, inductors or capacitors.

The support frame manufactured by the support frame manufacturing method provided by the embodiment of the application has the following advantages:

1) the circuit layer is prefabricated in the supporting frame in advance, so that the step of rewiring after embedding the chip is reduced, the defects possibly generated in the rewiring process on the embedded device are reduced, and the yield of products is improved.

2) The metal conductive posts and the sacrificial metal posts can be manufactured simultaneously, so that the production efficiency of the support frame is higher. Meanwhile, the metal conductive column can be designed into any shape according to different requirements, and the size and the shape of the embedded cavity can be flexibly adjusted, so that the metal conductive column has better flexibility and adaptability.

3) The circuit layer is prefabricated in the supporting frame in advance, so that the rigidity of the supporting frame can be increased, the thickness uniformity of the medium layer when the medium material is pressed can be improved, the risk of folding the supporting frame can be reduced, and the flatness of the embedded substrate can be improved.

4) The circuit layer is prefabricated in the supporting frame in advance, so that the glass fiber range exposed on the surface of the dielectric layer can be covered, the defects caused by glass fiber exposure are overcome, and the reliability of the supporting frame is improved.

Fig. 2 is a cross-sectional view of a supporting frame according to an embodiment of the present disclosure, as shown in the figure, the supporting frame 100 includes a dielectric layer 1, an embedded cavity 4 penetrating through the dielectric layer 1, and a metal conductive pillar 3 extending along a thickness direction of the dielectric layer 1, and a circuit layer 2 is formed on one side of the dielectric layer 1, where the circuit layer 2 is surrounded by the dielectric layer 1, an exposed surface of the circuit layer 2 is flush with a surface of the dielectric layer 1, and one end of the metal conductive pillar 3 is electrically connected to the circuit layer 2, and the other end of the exposed surface is flush with a surface of the dielectric layer 1.

Dielectric layer 1 is a polymer matrix, for example selected from the group consisting of polyimide, epoxy, bismaleimide/triazine resin (BT resin), polyphenylene oxide, polyacrylate, prepreg, and blends thereof.

In the description of the embodiments of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be configured in a specific orientation, and operate, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the embodiments of the present application, it should be noted that the terms "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected unless explicitly stated or limited otherwise; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. Specific meanings of the above terms in the embodiments of the present application can be understood in specific cases by those of ordinary skill in the art.

In addition, the technical features mentioned in the different embodiments of the present application can be combined with each other as long as they do not conflict with each other.

So far, the technical solutions of the present application have been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present application is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the present application, and the technical scheme after the changes or substitutions will fall into the protection scope of the present application.