KR20120115351A - Composite metal layer provided with supporting body metal foil, wiring board using the composite metal layer, method for manufacturing the wiring board, and method for manufacturing semiconductor package using the wiring board - Google Patents

Abstract

The waste produced by manufacture of a wiring board is reduced, and the composite metal layer with support metal foil which is preferable in a global environment, the wiring board using the same, its manufacturing method, and the manufacturing method of the semiconductor package using this wiring board are provided. A composite metal layer with a support metal foil, wherein a plurality of metal layers composed of a lowermost metal layer and two or more metal layers, which are support metal foils, are laminated between adjacent metal layers via a peeling layer, each positioned between the lowermost metal layer and the uppermost metal layer. The peeling strength between the metal layer (A) and the adjacent metal layer (B) via the peeling layer on the upper surface of the metal layer (A) and the adjacent metal layer (C) via the peeling layer on the lower surface thereof. It is smaller than the peeling strength in between, It is a composite metal layer with support metal foil, a wiring board using the same, its manufacturing method, and the manufacturing method of the semiconductor package using this wiring board.

Description

COMPOSITE METAL LAYER PROVIDED WITH SUPPORTING BODY METAL FOIL, WIRING BOARD USING THE COMPOSITE METAL LAYER, METHOD FOR MANUFACTURING THE WIRING BOARD, AND METHOD FOR MANUFACTURING SEMICONDUCTOR PACKAGE USING THE WIRING BOARD}

This invention relates to the composite metal layer with support metal foil suitable for the manufacturing method of the printed wiring board by the transfer method, the wiring board using the same, its manufacturing method, and the manufacturing method of the semiconductor package using this wiring board.

With the miniaturization and high performance of the device, the land area and wiring width for connecting circuit elements become finer, resulting in a decrease in the contact area between the land, the wiring, and the base material. It was made to embed the wiring in a base material. Various methods are proposed as a method of embedding lands and wirings in a base material. For example, a conductive pattern made of lands and wirings is formed by electroplating on a metal layer on a peelable support metal foil, followed by insulation made of a base material. The method of forming a layer is disclosed (patent document 1, patent document 2). On the insulating layer, a wiring layer is formed by a conventional method, and the formation of the insulating layer and the wiring layer is repeated as necessary, the metal layer is peeled from the support metal foil, and the metal layer is removed by etching, so that land and wiring are embedded in the substrate. Thus, a wiring board having a flat surface is obtained. This method is called a transfer method because a conductor pattern composed of lands and wirings on a metal layer is transferred to a base material, which is excellent in productivity and excellent in flatness of the obtained wiring board.

Moreover, the metal layer on the peelable support metal foil used for the above transfer methods is disclosed (patent document 3, patent document 4). These formed the peeling layer and the metal layer on the support metal foil, and after heat-processing at the curing temperature of a polyimide, and even if heat press by lamination for multilayering of a wiring board is performed in multiple times, between a support metal foil and a peeling layer The change of peeling strength is suppressed. For this reason, even after performing such heat processing and heat pressurization, since support metal foil can be peeled easily and peeling strength is stable, unexpected peeling does not occur at the time of handling, and it is excellent in workability.

Prior art literature

Patent literature

Patent Document 1: Republished Patent Publication WO2007 / 077735

Patent Document 2: Japanese Patent Publication No. 2005-101137

Patent Document 3: Republished Patent Publication WO2006 / 013735

Patent Document 4: Japanese Patent Publication No. 2003-094553

However, as in Patent Documents 1 and 2, when a conventional metal layer with a support metal foil is used, the support metal foil is discarded for each production of the wiring board. This support metal foil is refined after recovery as a resource and regenerated as a metal, but is not preferable as a global environment due to energy consumption.

In addition, as in Patent Document 2, when laminating an insulating layer on the support metal foil side of the metal layer with a support metal foil to form a support substrate, when the resin powder of the insulation layer adheres to the surface of the metal layer exposed on the surface side of the support substrate There is. Since the metal layer exposed to the surface side of the support substrate becomes a feed layer when the conductor pattern is formed by electroplating, the resin powder adhering to the metal layer forms a factor of lowering the yield when forming a fine conductor pattern. As a result, the waste may increase.

In addition, in the wiring boards of patent documents 1 and 2, after forming a conductor pattern on the metal layer of a support substrate by pattern copper plating, and forming an insulation layer or an interlayer connection thereon, the support substrate containing support metal foil is physically peeled off, Furthermore, a wiring board is produced by the process of forming a fine conductor pattern by removing the metal layer exposed after this peeling by etching. For this reason, a conductor pattern will not be formed and a wiring board will not be completed unless a part which turns into a wiring board finally becomes from a support metal foil, but in this case, when the completed wiring board is thin and low rigidity, in a mounting process, Warping may occur due to heating or weighting. Such warpage is a factor of lowering the mounting yield, and consequently, the possibility of causing an increase in waste is considered.

This invention is made | formed in view of the said problem, and by using a composite metal layer with a support metal foil, it becomes possible to manufacture a some wiring board with the composite metal layer with a support metal foil, a conductor pattern formation process, and a mounting process It is possible to improve the yield in the present invention, thereby reducing the waste generated during the manufacture of the wiring board and the semiconductor package, and the preferred metal metal layer with a support metal foil according to the global environment, the wiring board using the same and a manufacturing method thereof, and the semiconductor using the wiring board It is intended to provide a method of manufacturing a package.

The present invention relates to the following.

(1) A composite metal layer with a support metal foil, in which a plurality of metal layers composed of a lowermost metal layer and two or more metal layers, which are support metal foils, are laminated between adjacent metal layers via a peeling layer, between a lowermost metal layer and a metal layer of an uppermost layer. The peeling strength between each metal layer A located and the adjacent metal layer B through the peeling layer of the upper surface adjoins the metal layer C adjacent through the metal layer A and the peeling layer of the lower surface. The composite metal layer with a support metal foil characterized by being smaller than the peeling strength between and).

(2) The peeling strength between each metal layer (A) located between the lowest metal layer and the metal layer of the uppermost layer, and the adjacent metal layer (B) via the peeling layer on the upper surface thereof, the metal layer (A), The composite metal layer with a support metal foil as described in (1) characterized by being 20 N / m smaller than 5 N / m from peeling strength between adjacent metal layers (C) through the peeling layer of the lower surface.

(3) The composite metal layer with support metal foil as described in (1) or (2) characterized by the change rate before and after heating at 300 degreeC for 5 hours of the peeling strength between two adjacent metal layers via a peeling layer. .

(4) Pattern plating is performed on the metal layer of the uppermost layer of the composite metal layer with a support metal foil as described in any one of (1)-(3) (a), and a polyimide precursor is apply | coated on the metal layer containing this pattern plating (b) After preliminary drying and curing to form a polyimide (c), the polyimide with the metal layer is peeled off from the metal layer under the uppermost layer (d), and the metal layer remaining on the polyimide with the metal layer is removed to form the pattern plating. (A) to (e) are sequentially repeated on the uppermost surface of the composite metal layer with a support metal foil remaining after the polyimide is exposed to form a conductor pattern (e) and the polyimide with the metal layer is peeled off. The wiring board manufacturing method characterized by forming the wiring board of a hawk.

(5) The composite metal layer with a support metal foil according to any one of (1) to (3), wherein the metal layer (A) adjacent to the metal layer (C), which is the support metal foil, and the metal layer (C), via a release layer, and the metal layer Laminating the support metal foil side and the base material of the composite metal layer with a support metal foil having a metal layer (B) adjacent thereto via a release layer (A) to form a support substrate, and the metal layer (B) and the metal layer (A) A process of peeling a metal layer (B) from the surface of the said metal layer (A) with the peeling layer in between, the process of performing pattern plating on the metal layer (A) which remained on the said support substrate, and the metal layer containing the said pattern plating ( A) The manufacturing method of the wiring board which has the process of forming an insulating layer and wiring layer on it, and forming the wiring board with a support substrate.

(6) The method for manufacturing a wiring board according to (5), further comprising the step of forming a preliminary solder on the wiring layer on the uppermost layer after the step of forming the wiring board with the supporting substrate.

(7) The wiring board with a support substrate manufactured by the manufacturing method of the wiring board as described in (5) or (6).

(8) a step of mounting and sealing a semiconductor element on a wiring board with a supporting substrate manufactured by the method for manufacturing a wiring board according to (5) or (6), and forming a semiconductor package with a supporting substrate; From the step of leaving the metal layer (A) of the support substrate on the semiconductor package side, and peeling the support substrate together with the peeling layer between the metal layer (A) and the metal layer (C), and the metal layer (A) remaining on the semiconductor package side. A method of manufacturing a semiconductor package, which has a step of forming a conductor pattern by exposing the pattern plating to the surface of the insulating layer by removing the layer).

Carrying out the invention  Form for

Since the peeling layer used for the composite metal layer with a support metal foil of this invention does not require peeling strength to change with the thermal history of a wiring board manufacturing process, it can use not only organic substances, such as benzotriazole, but also inorganic substances using general chromium etc. A special release layer in which metals such as molybdenum and tungsten and their oxides are distributed by changing the composition in an oblique manner is preferably used. The oxide-rich layer in one release layer exhibits a peeling function, and the metal-rich layer prevents diffusion of copper to stabilize the peel strength. In addition, by changing the composition obliquely, misalignment of the thermal expansion coefficient or the like is alleviated, thereby contributing to the stabilization of the peel strength. The thickness of the release layer is preferably 50 nm to 40 nm.

As support metal foil, copper foil of 105 micrometers is preferable at thickness of 12 micrometers, and copper foil of 70 micrometers is especially preferable at thickness of 35 micrometers. As copper foil, any of electrolytic copper foil and rolled copper foil may be sufficient. As metal layers other than support metal foil which is a lowermost metal layer (henceforth a metal layer hereafter), the copper layer of 1 micrometer-5 micrometers in thickness is preferable, and the copper layer of 3 micrometers-5 micrometers in thickness is especially preferable. If the copper layer is thick, etching is required for a long time, and since it is easy to be uneven, there is a fear that the land is partially etched and the overall flatness is lost.

The composite metal layer with the support metal foil of the present invention does not need to be subjected to particularly heat resistance treatment, but it is preferable to perform a stabilization treatment for preventing surface deterioration during storage only in the uppermost metal layer. As such a treatment, there exists a waterproofing process and the chromate treatment by organic substance.

The peel strength between the metal layer (A) located between the lowest metal layer and the metal layer of the uppermost layer, and the adjacent metal layer and B via the peeling layer of the upper surface is the metal layer (A) and the peeling layer of the lower surface. It is preferable that it is smaller than peeling strength between metal layer (C) which adjoins through, and the difference is 5N / m to 20N / m in initial peeling strength. If the difference is small, it is stable and cannot be peeled off in sequence, and if it is large, peeling becomes difficult. Moreover, it is preferable that the rate of change before and after heating at 300 degreeC of peeling strength between two adjacent metal layers through a peeling layer for 5 hours is 25% or less.

An example of the manufacturing method of the wiring board using the composite metal layer with support metal foil of this invention is demonstrated. First, the metal oxide layer and the metal layer are formed on the support metal foil a predetermined number of times, and then the chromate treatment is performed only on the uppermost layer. After pattern plating is performed on the uppermost surface of the composite metal layer with a support metal foil formed in this way (a), it is washed with sulfuric acid and water is removed from the surface, and the polyimide precursor is applied to a thickness of 50 µm (b), followed by preliminary drying. Then, the mixture was cured at 300 ° C. for 2 hours to obtain polyimide (c). Subsequently, this polyimide with a metal layer is peeled from the lower metal layer (d), the metal layer remaining in this polyimide with a metal layer is etched, and the pattern plating performed previously is exposed from a polyimide, and a conductor pattern is formed (e). Next, said (a)-(e) are repeated one by one with respect to the uppermost surface of the composite metal layer with support metal foil remaining after peeling polyimide with a metal layer, and several wiring board is formed.

Other examples of the manufacturing method of the wiring board and the semiconductor package of the present invention will be described below with reference to FIGS. 1 to 8.

First, as shown in FIG. 1, support metal foil (or metal layer (C) may be called) 12, peeling layer 14, metal layer A11, peeling layer 13, and metal layer B10 The composite metal layer 9 with support metal foil laminated | stacked from this side in this order is prepared.

The metal layer B is for protecting the surface (interface with the metal layer B10) of the metal layer A11, and becomes physically peelable at the interface with the metal layer A11. At the interface between the metal layer B10 and the metal layer A11, a release layer 13 for stabilizing the peel strength at the interface is provided. As a peeling layer, even if heating and pressurization at the time of laminating | stacking an insulating layer and a conductor layer are preferable, it is preferable that peeling strength is stabilized. As such a peeling layer 13, what contains Ni and W metal oxide or Ni and Mo metal oxide, what consists of Cu-Ni-Mo alloy, etc. which are disclosed by patent documents 3 and 4 are mentioned. Can be mentioned. Moreover, when this peeling layer 13 physically peels the metal layer B10 at the interface with the metal layer A11, it peels in the state which adhered to the metal layer B10 side, and remains on the surface of the metal layer A11. It is desirable not to.

The metal layer A11 becomes a power supply layer which supplies an electric current in order to perform pattern plating 18 on the surface after peeling the metal layer 10, and interfaces with the metal layer B10, and support metal foil (or metal layer C) It becomes possible to peel physically at the interface with ()) 12. When forming the conductor pattern 2 (FIG. 8 (16)) as described later, since the etching pattern is removed, in order to reduce the gap of the etching amount as much as possible and to form a high-precision microcircuit, the ultra-thin of 1 μm to 5 μm (Iii) Metal foil is preferable and 3 micrometers-5 micrometers are especially preferable. In addition, at the interface with the metal layer (B10) and the support metal foil (or metal layer (C)) 12, the above-described release layers 13 and 14 are provided in order to stabilize the peel strength at the interface. do.

The support metal foil (or metal layer (C)) 12 is disposed on the side laminated with the base 16 when the composite metal layer 9 with the support metal foil is laminated with the base 16 to form the support substrate 17. It is possible to peel physically at the interface with the metal layer A11. When laminated | stacked with the base material 16, if it has adhesiveness with the base material 16, a material and thickness will not be specifically asked, In terms of versatility and handleability, copper foil and aluminum foil are preferable as a material, As thickness, it is 12 micrometers-105 micrometers. Is preferable and 35 micrometers-70 micrometers are especially preferable. In addition, the peeling layer 14 as mentioned above is provided in the interface with the metal layer A11 in order to stabilize peeling strength in an interface.

As the composite metal layer 9 with a support metal foil, it has three or more metal layers (for example, metal layer B10, metal layer A11, support metal foil (or metal layer (C)) 12, as above-mentioned), and at least Two interfaces (for example, as described above, the interface between the metal layer B10 and the metal layer A11 and the interface between the metal layer A11 and the support metal foil (or metal layer (C)) 12 physically) In the case of the process of laminating | stacking the base material 16 on the support metal foil (or metal layer (C)) 12 side of the composite metal layer 9 with support metal foil 9, and forming the support substrate 17, a metal layer B10 is used. Although foreign matters such as resin powder may adhere to the surface of), even if such foreign matters adhere, the effect of foreign substances such as resin powder may be caused by physically peeling the metal layer B10 at the interface with the metal layer A11. Since the surface of the metal layer A11 is absent, high-quality metal It is possible to ensure the surface. Therefore, even in the case of performing the plating metal layer pattern (18) using as a power supply layer (A11), it is possible to suppress the occurrence of defects, it is possible to improve the yield.

In the following FIGS. 2 to 8, the release layer 13 is disposed between the metal layer B10 and the metal layer A11, and the release layer is disposed between the metal layer A11 and the metal layer C12, similarly to FIG. 1. Although 14 is provided, illustration is abbreviate | omitted. Next, as shown in Fig. 2 (1), the support metal foil (or metal layer (C)) 12 side of the composite metal layer with support metal foil 9 and the base material 16 are laminated to form the support substrate 17. do. The base material 16 is laminated | stacked and integrated with the composite metal layer 9 with support metal foil, and forms the support substrate 17. As the base material 16, what is generally used as the insulating layer 3 of a wiring board can be used. . In addition, the metal foil 15 may be laminated and integrated in addition to the composite metal layer 9 and the base material 16 with a support metal foil. As such a base material 16, glass epoxy, glass polyimide, etc. are mentioned. The support substrate 17 uses the composite metal layer 9 with a support metal foil to secure rigidity when manufacturing a wiring board, thereby improving workability and preventing damage during handling to improve yield. To play a major role. For this reason, it is preferable to have reinforcing materials, such as glass fiber, as the base material 16, For example, the prepreg, such as glass epoxy and glass polyimide, overlaps with the composite metal layer 9 with support metal foil, and a hot press etc. It can form by laminating | stacking and integrally by heating and pressurizing using it.

Next, as shown in FIG. 2 (2), the metal layer B10 is physically peeled off at the interface between the metal layer B10 and the metal layer A11 of the composite metal layer 9 with the support metal foil. Foreign materials, such as resin powder from the prepreg etc. which become the material of the base material 16 at the time of lamination, may adhere to the surface of the metal layer B10. For this reason, when forming the conductor pattern 2 using this metal layer B10, defects, such as a disconnection and a short circuit, are formed in the conductor pattern 2 by the foreign material, such as resin powder which affixed on the surface. It may occur, and may lead to the fall of a yield. However, by peeling and removing the metal layer B10 in this manner, the conductor pattern can be formed using the metal layer A11 to which foreign substances such as resin powder are not attached, so that the occurrence of circuit defects can be suppressed. Therefore, it becomes possible to improve the yield. In addition, since the metal layer B10 can be physically peeled off, the peeling operation can be easily performed by adjusting the peel strength of the interface between the metal layer B10 and the metal layer A11.

Here, the composite metal layer 9 with a support metal foil has a peel strength at the interface between the metal layer A11 and the support metal foil (or the metal layer C) 12 is larger than the peel strength at the interface between the metal layer B10 and the metal layer A11 Is preferably formed larger than the peel strength. Thereby, when physically peeling at the interface of the metal layer B10 and the metal layer A11, it can suppress that the interface of the metal layer A11 and support metal foil (or metal layer (C)) 12 peels simultaneously. Can be. As peeling strength, in the initial stage before a heating, in the interface of metal layer B10 and metal layer A11, 2N / m-50N / m, metal layer A11, and support metal foil (or metal layer (C)) 12 It is 10N / m-70N / m at an interface, and peeling strength of the interface of metal layer B10 and metal layer A11 is the peeling strength of the interface of metal layer A11 and support metal foil (or metal layer (C)) 12. When it becomes 5 N / m-20 N / m smaller than it, it does not peel by handling in a manufacturing process, On the other hand, it is easy at the time of peeling, Moreover, when peeling metal layer B10, the metal layer A11 peels off simultaneously. Since work can be suppressed, workability is good.

Adjustment of peeling strength becomes possible by adjusting the plating liquid composition and conditions for forming the metal oxide and alloy plating layer which become a peeling layer as shown, for example in patent documents 3 and 4, for example.

Next, as shown in FIG. 2 (3), pattern plating 18 is performed on the metal layer A11 remaining on the support substrate 17. As described above, foreign matters such as resin powder from the prepreg and the like used at the time of lamination are not adhered to the surface of the metal layer A11 (interface with the metal layer B10). It becomes possible to suppress it. Pattern plating 18 can be performed using electroplating, after forming a plating resist (not shown) on metal layer A11. As a plating resist, the photosensitive resist used at the manufacturing process of a wiring board can be used. As electroplating, copper sulfate plating etc. which are used at the manufacturing process of a wiring board can be used.

Next, as shown in FIG. 3 (4), the insulating layer 3 is laminated on the metal layer A11 containing the pattern plating 18, and the wiring board 22 with a support substrate is formed. At this time, you may laminate | stack the metal foil used as the conductor layer 20 simultaneously. As the insulating layer 3, what is generally used as the insulating layer 3 of a wiring board can be used. As such insulating layer 3, epoxy resin, polyimide resin, etc. are mentioned, For example, prepregs, such as an epoxy-type and polyimide-type adhesive sheet, glass epoxy, and glass polyimide, are hot-pressed. It can form by laminating | stacking and integrally heating and pressing using etc. As a metal foil used as the conductor layer 20, the copper foil used by manufacture of a wiring board is preferable.

Next, as shown to FIG.3 (5), (6), the interlayer connection hole 21 may be formed and the interlayer connection 5 and the wiring layer 6 may be formed. The interlayer connection 5 can be formed by, for example, plating the inside of the interlayer connection hole 21 after forming the interlayer connection hole 21 using a so-called conformal method. For this plating, after plating thin electroless copper plating is performed as base plating, electroless copper plating, electroplating copper plating, field-bearing plating, etc. can be used as backside plating. In order to reduce the thickness of the conductor layer 20 to be etched and to easily form a microcircuit, it is preferable to form a plating resist after the base plating of the thin film, and to perform the back plating by electroplating or field via plating. The wiring layer 6 can be formed by, for example, plating the interlayer connecting holes 21 by removing the conductor layer 20 in the unnecessary portion by etching.

Next, as shown in Figs. 4 (7), (8) and 5 (9), (10), the insulating layer 3 and the conductor layer 20 on the wiring layer 6 and the interlayer connection 5. ), The pattern plating 18 is further formed, and the wiring layer 6 and the interlayer connection 5 can be formed so that it may become a desired number of layers similarly to the time of FIG. 3 (5), (6). By forming the wiring board 22 with the supporting substrate in this way, since the supporting substrate 17 ensures rigidity, it is possible to improve the workability, to prevent damage during handling, and to improve the yield.

Next, as shown in Figs. 6 (11) and (12), after the wiring layer 6 is formed, the solder resist 4 or the protective plating 8 is formed at a desired location as necessary. As protective plating 8, nickel plating and gold plating which are used as protective plating 8 of the connection terminal of a wiring board are preferable.

Next, as shown in Fig. 7 (13), if necessary, the preliminary solder 19 may be formed again at a desired position of the upper wiring layer. The preliminary solder 19 can be formed by a method of printing and reflowing a solder paste. Thus, by forming preliminary solder in the state of the wiring board 22 with a support substrate, even if it is easy to produce warpage and a deformation | transformation in the heating at the time of solder reflow, wiring board alone can suppress curvature and a deformation | transformation. The yield at the time of mounting improves. In addition, by providing the preliminary solder 19 on the wiring board side, the solder applying step in the step of mounting the semiconductor element 7 can be omitted, and the number of steps can be reduced.

Next, as shown in FIG. 7 (14), the semiconductor device 7 is mounted (bump 25) and encapsulated by the sealing resin 23 to form a semiconductor package 24 with a supporting substrate. In this way, by mounting or encapsulating the semiconductor element 7 using the support board 17 with the support board as the support board 17 is installed, the wiring board is thin and does not have rigidity, and warpage and deformation are performed. Even when it is easy to produce, since the support substrate 17 ensures rigidity and suppresses warpage and deformation, the mounting yield is improved.

Next, as shown in Fig. 8 (15), in the semiconductor package 24 with the supporting substrate, the metal layer A11 and the support metal foil (or metal layer (C)) 12 of the composite metal layer 9 with the support metal foil (12). At the interface with the semiconductor package 26, the semiconductor package 26 is physically peeled off from the supporting substrate 17 together with the metal layer A11. That is, from the semiconductor package 24 with a support substrate, the metal layer A11 of the support substrate 17 is left to the semiconductor package 26 side, and the peeling layer 14 between the metal layer A11 and the metal layer C12 is carried out. The support substrate 17 is peeled off together.

Next, as shown in FIG. 8 (16), the metal layer A11 remaining on the bottom surface of the separated semiconductor package 26 is removed by etching or the like, so that the pattern plating 18 is removed from the surface of the insulating layer 3. Is exposed to form a conductor pattern (2). Thereby, when forming the conductor pattern 2, since the side surface of the conductor pattern 2 is not eroded by etching, since an undercut does not occur, the fine conductor pattern 2 can be formed. In addition, since the conductor pattern 2 formed in the present invention is embedded in the insulating layer 3, not only the bottom surface of the conductor pattern 2 but also the side surfaces on both sides are in close contact with the insulating layer 3. Even in a fine circuit, sufficient adhesiveness can be ensured. Moreover, when the ultra-thin copper foil with a thickness of 1 micrometer-5 micrometers is used as the metal layer A11, since the metal layer A11 can be removed even with a slight etching amount, it is embedded in the insulating layer 3, and the insulating layer 3 The surface of the conductor pattern 2 exposed from the surface is flat, and connection reliability can be ensured, and it is also suitable to be used as a connection terminal.

By using the composite metal layer with a support metal foil of this invention, it becomes possible to manufacture several wiring board with the composite metal layer with a support metal foil, and it is possible to aim at the yield improvement in a conductor pattern formation process and a mounting process. By reducing the waste generated in the manufacture of the wiring board and the semiconductor package, a composite metal layer with a support metal foil suitable for the global environment, a wiring board using the same, a manufacturing method thereof, and a manufacturing method of the semiconductor package using the wiring board can be provided. have.

1 is a cross-sectional view of a composite metal layer with a support metal foil of the present invention.
2 is a flowchart showing a part of the manufacturing method of the wiring board of the present invention.
3 is a flowchart showing a part of the manufacturing method of the wiring board of the present invention.
4 is a flowchart showing a part of the manufacturing method of the wiring board of the present invention.
5 is a flowchart showing a part of the manufacturing method of the wiring board of the present invention.
6 is a flowchart showing a part of the manufacturing method of the wiring board of the present invention.
7 is a flowchart showing a part of the manufacturing method of the wiring board and the semiconductor package of the present invention.
8 is a flowchart showing a part of the manufacturing method of the semiconductor package of the present invention.

Example

Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples.

1. Preparation of the composite metal layer with the support metal foil

As the support metal foil, an electrolytic copper foil having a thickness of 18 µm was used, which was pickled with 30 g / L sulfuric acid as a pretreatment, and then a peeling layer was formed on the surface of the glossy surface (Ni 30 g / L, Mo 3.Og / L, citric acid). The metal oxide layer is formed in a bath having a composition of 30 g / L). In addition, the amount of metal oxide is adjusted by current.

Next, in a bath of a metal layer (copper sulfate 200 g / L, sulfuric acid 100 g / L), electrolytic plating was performed and plating was performed up to 5 µm.

After the predetermined number of times of formation of the metal oxide layer and the metal layer, the chromate treatment was performed only on the uppermost layer. The peeling strength for every metal layer of the obtained composite metal layer with support metal foil was measured. Moreover, this composite metal layer with a support metal foil was heated at 300 degreeC for 5 hours, peeling strength was measured for every layer, and the change rate was calculated | required. Moreover, adjustment of peeling strength was performed by the thickness of a metal oxide layer. Table 1 shows the measurement results of the peel strength.

The composite metal layers (A) and B with a support metal foil shown in Table 1 were specifically manufactured as follows (Example 1) and (Example 2).

(Example 1)

Preparation of the composite metal layer (A) with a support metal foil

(1) The support metal foil was immersed in 30 g / L of sulfuric acid for 30 seconds using an electrolytic copper foil having a thickness of 18 µm, and washed with water for 30 seconds after washing with acid.

(2) 30 g / L of nickel sulfate hexahydrate, 30 g / L of sodium molybdate dihydrate 3.Og / L, and 3 g of sodium citrate dihydrate 30 g / L , electrolytic treatment at a current of 20 A / dm ² for 5 seconds on the glossy surface of the electrolytic copper foil in a bath at pH 6.0 and a liquid temperature of 30 ° C. to form a release layer 1 containing a metal oxide composed of nickel and molybdenum.

(3) A current density of 4 A / dm ² is obtained by using a Ti electrode plate coated with iridium oxide as a positive electrode on a surface after forming the release layer 1 in a bath of 200 g / L copper sulfate pentahydrate, 100 g / L sulfuric acid, and a liquid temperature of 40 ° C. Electrolytic plating was performed for 340 seconds to form a metal layer 1 having a thickness of 5 m.

(4) The surface after formation of the metal layer 1 was subjected to electrolytic treatment at a current density of 10 A / dm ² for 10 seconds using the same bath as in (2), to form a release layer 2 containing a metal oxide composed of nickel and molybdenum.

(5) Electrolytic plating was performed on the surface after formation of the release layer 2 using a bath similar to (3) at a current density of 4 A / dm ² for 340 seconds to form a metal layer 2 having a thickness of 5 m.

(6) The metal layer 2 was electrolytically treated at a current density of 5 A / dm ² for 20 seconds using the same bath as in (2), and a release layer 3 containing a metal oxide composed of nickel and molybdenum was formed.

(7) Electrolytic plating was performed on the surface after formation of the release layer 3 using the same bath as in (3) at a current density of 4 A / dm ² for 340 seconds to form a metal layer 3 having a thickness of 5 m.

(8) The surface after formation of the metal layer 3 was electrolytically treated at a current density of 2 A / dm ² for 50 seconds using the same bath as in (2) to form a release layer 4 containing a metal oxide composed of nickel and molybdenum.

(9) Electrolytic plating was performed on the surface after formation of the peeling layer 4 using the same bath as in (3) for 340 seconds at a current density of 4 A / dm ² to form a metal layer 4 having a thickness of 5 m.

(10) 1 current density of 30 A / dm using a plating bath (limit current density 15 A / dm ² ) adjusted to 150 g / L copper sulfate pentahydrate, 100 g / L sulfuric acid, and liquid temperature 30 ° C. on the surface after formation of metal layer 4 Electrolytic treatment was carried out with ² for 3 seconds, and electrolytic treatment with 2 current densities 5A / dm ² for 80 seconds to form a roughened layer made of cove-like copper particles.

(11) Next, the surface after formation of a roughened layer was electrolyzed at a current density of 0.5 A / dm ² for 2.5 seconds using an aqueous solution adjusted to 3.5 g / L sodium dichromate dihydrate, pH 4.0, and a liquid temperature of 28 ° C. The chromate layer was formed on the roughening layer.

(12) After immersion in an aqueous solution of 0.1% by weight of 3-glycidoxypropyltrimethoxysilane on the surface on which the chromate layer was formed, it was immediately dried at 80 ° C to form a silane coupling agent treatment layer on the chromate layer.

(Example 2)

Preparation of the composite metal layer (B) with a support metal foil

(1) The support metal foil was immersed in 30 g / L sulfuric acid for 60 seconds using an electrolytic copper foil having a thickness of 18 µm, and washed with water for 30 seconds after flowing with acid.

(2) 30 g / L nickel sulfate hexahydrate, 30 g / L sodium molybdate dihydrate 3.Og / L, trisodium citrate dihydrate 30 g / L , a pH 6.0 and a bath temperature of 30 ° C. were electrolytically treated at a gloss surface of the electrolytic copper foil for 4 seconds at a current density of 25 A / dm ² to form a release layer 1 containing a metal oxide composed of nickel and molybdenum.

(3) A current density of 4 A / dm ² is obtained by using a Ti electrode plate coated with iridium oxide as a positive electrode on a surface after forming the release layer 1 in a bath of 200 g / L copper sulfate pentahydrate, 100 g / L sulfuric acid, and a liquid temperature of 40 ° C. Electrolytic plating was performed for 340 seconds to form a metal layer 1 having a thickness of 5 m.

(4) The metal layer 1 was electrolytically treated at the current density of 20 A / dm <^2> for 5 second using the same bath as (2), and the peeling layer 2 containing the metal oxide which consists of nickel and molybdenum was formed.

(5) Electrolytic plating was performed on the surface after formation of the release layer 2 using a bath similar to (3) at a current density of 4 A / dm ² for 340 seconds to form a metal layer 2 having a thickness of 5 m.

(6) The surface of the metal layer 2 after the formation thereof was electrolytically treated at a current density of 10 A / dm ² for 10 seconds by using the same bath as in (2) to form a release layer 3 containing a metal oxide of nickel and molybdenum.

(7) Electrolytic plating was performed on the surface after formation of the release layer 3 using the same bath as in (3) at a current density of 4 A / dm ² for 340 seconds to form a metal layer 3 having a thickness of 5 m.

(8) The metal layer 3 was electrolytically treated with the current density of 2.5 A / dm <^2> for 40 second using the same bath as (2), and the peeling layer 4 containing the metal oxide which consists of nickel and molybdenum was formed. .

(9) Electrolytic plating was performed on the surface after formation of the peeling layer 4 using the same bath as in (3) for 340 seconds at a current density of 4 A / dm ² to form a metal layer 4 having a thickness of 5 m.

(10) The same process as (12) of (1) of Example 1 was performed to the surface of the metal layer 4, and the roughening layer, the chromate layer, and the silane coupling agent process layer were formed one by one.

2. Evaluation of Peelability

The surface of the uppermost layer was washed with sulfuric acid to remove moisture from the surface, and a polyimide precursor (trade name: U-Vanis-A manufactured by Ubegosan Co., Ltd.) was applied to a thickness of 50 µm, and after preliminary drying, it was cured at 300 ° C. for 2 hours to obtain poly It was mid. Subsequently, this polyimide with a metal layer was peeled from the lower metal layer. Furthermore, polyimide was similarly formed in this exposed metal layer, and peeling was repeated one by one. Table 1 shows the results of visual evaluation of the peelability.

Item
Composite metal layer with support metal foil (A)
Composite metal layer B with support metal foil
Early stage
Peel strength Peel strength
Rate of change Peelability Early stage
Peel strength Peel strength
Rate of change Peelability Support metal foil
Metal layer 1 46.9 9 ○ 68.4 5 ○ Metal layer 1
The metal layer above it 2 29.1 13 ○ 46.9 8 ○ With metal layer 2
The metal layer above it 3 15.3 21 ○ 28.1 11 ○ Metal layer 3
The metal layer above it 4 2.2 5 ○ 3.6 6 ○

Initial Peel Strength: N / m,% Change in Peel Strength

3. Manufacture of wiring board

(Example 3)

First, as shown in FIG. 1, support metal foil (or metal layer (C) may be called) 12, peeling layer 14, metal layer A11, peeling layer 13, and metal layer B10 And the composite metal layer 9 with support metal foil laminated | stacked from this side in this order was prepared. In this Example, although the composite metal layer 9 with support metal foil was produced on the conditions similar to the composite metal layer 9 with support metal foil of Table 1, the number of metal layers is support metal foil (metal layer (C)) 12 and a metal layer. It is three layers of (A11) and the metal layer (B10). The peeling strength of each metal layer was adjusted with reference to the manufacturing conditions of the composite metal layer 9 with support metal foil of Table 1. As peeling strength of a metal layer, in the initial stage before a heating, it is 2N / m-50N / m, the metal layer A11 and support metal foil (or metal layer (C)) 12 at the interface of metal layer B10 and metal layer A11. ) Is 10 N / m to 70 N / m, and the peel strength of the interface between the metal layer B10 and the metal layer A11 is between the metal layer A11 and the support metal foil (or metal layer (C)) 12. It was made to become 5N / m-20N / m smaller than the peeling strength of an interface.

In the following FIGS. 2 to 8, the release layer 13 is disposed between the metal layer B10 and the metal layer A11, and the release layer is disposed between the metal layer A11 and the metal layer C12, similarly to FIG. 1. Although 14 is provided, illustration is abbreviate | omitted. Next, as shown in FIG. 2 (1), the prepreg made of glass epoxy which consists of the support metal foil (or metal layer (C)) 12 side of the composite metal layer 9 with support metal foil, and the base material 16; The copper foil which consists of metal foil 15 was laminated | stacked using the hot press, and the support substrate 17 was formed.

Next, as shown in FIG. 2 (2), the metal layer B10 was physically peeled off at the interface between the metal layer B10 and the metal layer A11 of the composite metal layer 9 with the support metal foil. On the surface of the metal layer B10, foreign materials such as resin powder from prepreg, etc., which are used as the material of the base material 16, adhered to the surface of the metal layer B10. However, by removing the metal layer B10 and removing the metal powder B10, The metal layer A11 which the foreign material did not adhere to was prepared.

Next, as shown in FIG. 2 (3), a photosensitive plating resist was formed on the metal layer A11 remaining on the support substrate 17, and pattern plating 18 was performed using copper sulfate electroplating.

Next, as shown in FIG. 3 (4), on the metal layer A11 including the pattern plating 18, an epoxy-based adhesive sheet and a copper foil are laminated by hot press to insulate the insulating layer 3 and the conductor layer 20. ) Was formed and the wiring board 22 with a support substrate was produced.

Next, as shown in Figs. 3 (5) and (6), after the interlayer connection hole 21 is formed by using the conformal method, thin electroless copper plating is performed in the interlayer connection hole 21. The interlayer connection 5 and the wiring layer 6 were formed by forming a plating resist, performing pattern electroplating, and removing the extra conductor layer 20 by etching after peeling the plating resist.

Next, as shown in Figs. 4 (7), (8) and 5 (9), (10), the insulating layer 3 and the conductor layer 20 on the wiring layer 6 and the interlayer connection 5. ), Pattern plating 18 was further formed, and the wiring layer 6 and the interlayer connection 5 were formed so that it may become a desired number of layers similarly to the time of FIG. 3 (5), (6).

Next, as shown in FIGS. 6 (11) and 12, after the wiring layer 6 was formed, the solder resist 4 and the protective plating 8 were formed. As the protective plating 8, nickel plating and gold plating used as the protective plating 8 of the connection terminal of a wiring board were used.

Next, as shown in FIG. 7 (13), the preliminary solder 19 was formed again at the predetermined position of the upper wiring layer 6. The preliminary solder 19 was formed by a method of printing and reflowing a solder paste.

4. Manufacturing of Semiconductor Packages

(Example 4)

Next, as shown in Fig. 7 (14), the semiconductor element 7 was mounted and encapsulated with the encapsulating resin 23 to form a semiconductor package 24 with a supporting substrate.

Next, as shown in Fig. 8 (15), in the semiconductor package 24 with the supporting substrate, the metal layer A11 and the support metal foil (or metal layer (C)) 12 of the composite metal layer 9 with the support metal foil (12). At the interface with, the semiconductor package 26 was physically peeled off from the supporting substrate 17 together with the metal layer A11. That is, the metal layer A11 of the support substrate 17 is left on the side of the semiconductor package 26 from the semiconductor package 24 with the support substrate, and the release layer 14 between the metal layer A11 and the metal layer C12, The support substrate 17 was peeled off.

Next, as shown in FIG. 8 (16), the metal layer A11 remaining on the bottom surface of the separated semiconductor package 26 is removed by etching or the like, so that the pattern plating 18 is removed from the surface of the insulating layer 3. It exposed to and formed the conductor pattern 2.

2: conductor pattern
3: insulation layer
4: solder resist
5: interlayer connection
6: wiring layer
7: semiconductor device
8: protective plating
9: composite metal layer with support metal foil
10: metal layer (B)
11: metal layer (A)
12: support metal foil or metal layer (C)
13: release layer
14: release layer
15: metal foil
16: description
17: support substrate
18: pattern plating
19: preliminary solder
20: conductor layer
21: interlayer connection hole
22: wiring board with support substrate
23: bag resin
24: semiconductor package with support substrate
25 bump
26: semiconductor package

Claims (8)

A composite metal layer with a support metal foil, wherein a plurality of metal layers composed of a lowermost metal layer and two or more metal layers, which are support metal foils, are laminated between adjacent metal layers via a peeling layer, each positioned between the lowermost metal layer and the uppermost metal layer. The peeling strength between the metal layer (A) and the adjacent metal layer (B) via the peeling layer on the upper surface of the metal layer (A) and the adjacent metal layer (C) via the peeling layer on the lower surface thereof. It is smaller than peeling strength between, The composite metal layer with support metal foil characterized by the above-mentioned. The peeling strength of each metal layer (A) located between the lowest metal layer and the uppermost metal layer, and the adjacent metal layer (B) via the peeling layer of the upper surface is a metal layer (A). ) And from 20 N / m to 20 N / m smaller than the peel strength between the adjacent metal layer (C) via the peeling layer on the lower surface thereof. The composite metal layer with a support metal foil according to claim 1 or 2, wherein a rate of change before and after heating at 300 ° C. for 5 hours of peel strength between two adjacent metal layers via a peeling layer is 25% or less. Pattern plating is performed on the metal layer of the uppermost layer of the composite metal layer with a support metal foil as described in any one of Claims 1-3, (a), and a polyimide precursor is apply | coated on the metal layer containing this pattern plating (b), and preliminary After drying and curing to form a polyimide (c), the polyimide with a metal layer is peeled from the metal layer of the lower layer of the uppermost layer (d), and the metal layer remaining on the polyimide with the metal layer is removed to form the polyimide. Exposing from (a), and forming a conductor pattern (e), and repeating the above (a) to (e) sequentially on the surface of the uppermost layer of the composite metal layer with a support metal foil remaining after the polyimide with the metal layer is peeled off. A wiring board manufacturing method, characterized by forming a wiring board. The composite metal layer with a support metal foil as described in any one of Claims 1-3 WHEREIN: The metal layer (A) which is adjacent to a metal layer (C) which is a support metal foil, and a metal layer (C) via a peeling layer, and a metal layer (A) Laminating the support metal foil side and the base material of the composite metal layer with a support metal foil having an adjacent metal layer (B) through a peeling layer) to form a support substrate, and between the metal layer (B) and the metal layer (A). The process of peeling a metal layer (B) from the surface of the said metal layer (A) with a peeling layer, the process of performing pattern plating on the metal layer (A) remaining on the said support substrate, and the metal layer (A) containing the said pattern plating The manufacturing method of the wiring board which has a process of forming an insulating layer and wiring layer on it, and forming the wiring board with a support substrate. The manufacturing method of the wiring board of Claim 5 which further has a process of forming a preliminary solder in the wiring layer of an uppermost layer, after the process of forming a wiring board with a support substrate. The wiring board with a support substrate manufactured by the manufacturing method of the wiring board of Claim 5 or 6. The process of mounting and sealing a semiconductor element in the wiring board with a support substrate manufactured by the manufacturing method of the wiring board of Claim 5 or 6, and forming a semiconductor package with a support substrate, It supports from the semiconductor package with a support substrate. Leaving the metal layer (A) of the substrate on the semiconductor package side, and peeling the supporting substrate together with the peeling layer between the metal layer (A) and the metal layer (C), and removing the metal layer (A) remaining on the semiconductor package side. And exposing pattern plating to the surface of an insulating layer, thereby forming a conductor pattern.

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