TWI765366B - Metal carrier and method for producing the same - Google Patents

Abstract

The metal carrier of the present invention comprises a heat-resistant base layer, a first metal layer, a second metal layer and a third metal layer, wherein the first metal layer is formed on the surface of the base layer by a sputtering process, and the second metal layer is formed by a chemical wet process In the formed ultra-thin copper foil, the third metal layer is a roughened molybdenum alloy formed by a sputtering process, and the first metal layer and the second metal layer have peelability; the metal carrier of the present invention is in the third metal layer. The backside of the metal layer is bonded to the film, and the base layer and the first metal layer are torn apart from the metal carrier to form the film structure of the present invention, which includes an adhesive layer, a seed layer and a metal layer, which can be used to manufacture a thin film circuit board. Compared with the prior art, the metal carrier of the present invention has higher controllability of copper foil thickness, reduced manufacturing equipment cost and better production yield.

Description

Metal carrier and method for producing the same

The invention belongs to the field of circuit board manufacturing, in particular to a detachable metal carrier with ultra-thin metal.

With the development of science and technology, the technology of mobile consumer electronic devices is getting better and more sophisticated, and the volume is constantly shrinking, which drives electronic components to increase the utilization rate per unit area. For this reason, the circuit design of the circuit board is tighter and the line width is thinner. narrow.

As the line width gets thinner and thinner, the thickness of the copper foil on the circuit board must also be converted to ultra-thin copper foil. However, as the thickness of the copper foil decreases, its toughness also decreases, causing circuit board manufacturers to use the hot rolling process. When the ultra-thin copper foil is attached to the polyimide (P.I, Polyimide), polyethylene terephthalate (polyethylene terephthalate, P.E.T) or film (Prepreg, P.P) substrate, the copper foil is prone to breakage. .

Please refer to FIG. 1 , which is a schematic diagram of a double copper foil in the prior art. In order to reduce the breakage of ultra-thin metal foils in the prior art, a double copper foil 1 is provided, which includes a thick copper foil layer 11 , a peeling layer 12 and a thin copper foil 13 . When a circuit board manufacturer uses a hot rolling process to roll the double copper foil 1 When it is attached to the substrate, because of the support of the thick copper foil layer 11, the toughness of the thin copper foil 13 is increased, and the probability of the copper foil breaking is reduced.

However, the above-mentioned manufacturing method of the prior art is formed by laminating two layers of standard-thickness copper foils and rolling them with several kilometers of rolling equipment. The manufacturing process is time-consuming and energy-consuming, and it is difficult to control the thin copper foils. The thickness of 13, especially the production yield of thin copper foil 13 below 5 μm is even worse, requiring longer rolling equipment to manufacture, which increases equipment investment cost during manufacturing.

In view of the shortcomings of the above-mentioned prior art, the creator of this case has been eager to improve and innovate, and after years of painstaking research, he has finally successfully developed the metal carrier, the manufacturing method and the thin film structure of the present invention.

In order to solve the above-mentioned problems of the prior art, the present invention provides a metal carrier, a manufacturing method and a thin film structure, the objectives of which are: 1. Improve the controllability of the thickness of the ultra-thin copper foil; 2. Reduce the complexity and cost of manufacturing equipment; 3. Improve the production yield of ultra-thin copper foil circuit boards; 4. Simplify the etching process.

The metal carrier of the present invention comprises in sequence: a heat-resistant base layer made of polyimide, a first metal layer, a second metal layer and a third metal layer, wherein the first metal layer and the second metal are the same A metal, and the peel strength between the two layers is 0.15 to 3kgf/cm, wherein the third metal layer is an alloy containing molybdenum, and one side of the third metal layer is a rough surface, and has an arithmetic mean roughness of 20-500nm degree (Ra).

The manufacturing method of the metal carrier of the present invention comprises: using polyimide (P.I, Polyimide) as a base layer, sputtering a layer of copper on the base layer to form a first metal layer, and adding copper on the first metal layer by a chemical wet process The thickness of the second metal layer is formed, and a molybdenum-niobium alloy is sputtered on the second metal layer to form the third metal layer.

The thin film structure of the present invention includes an adhesive layer made of a film (PP, Prepreg), a seed layer made of an alloy containing molybdenum, and a metal layer made of one of gold, silver, copper and iron.

As mentioned above, the metal carrier and the manufacturing method of the present invention have better copper foil thickness controllability and manufacturing yield compared with the prior art. In addition, the production line of the present invention is simpler and does not require large-scale manufacturing equipment, so it has the advantages of The advantage of lower cost of manufacturing equipment.

Furthermore, in the thin film structure of the present invention, both the copper foil and the molybdenum alloy can be cleaned by the copper chloride-based etching solution, so the thin film structure of the present invention only needs to use one etching production line to complete the circuit fabrication, thereby achieving simplification. Etching steps, the effect of reducing the cost of etching equipment and raw materials.

1: Double copper foil

11: Thick copper foil layer

12: Peel layer

13: Thin copper foil

2: with metal carrier

21: Base Layer

22: The first metal layer

23: Second metal layer

24: The third metal layer

4: Semi-finished products of thin film circuit boards

41: Base Layer

42: first metal layer

43: Second metal layer

44: Third metal layer

45: Film

5: Thin film structure

51: Adhesive layer

52: Seed Layer

53: Metal layer

S301-S302: Steps

S601-S604: Steps

Figure 1 is a schematic diagram of the double copper foil in the prior art; Figure 2 is a schematic diagram of the metal carrier of the present invention; Figure 3 is a flowchart of the application of the metal carrier of the present invention to the production of a thin film structure; Figure 4 is a schematic diagram of the present invention. The schematic diagram of the semi-finished product of the thin film structure of the present invention; FIG. 5 is the schematic diagram of the thin film structure of the present invention; FIG. 6 is the flow chart of the manufacturing method of the metal carrier of the present invention.

In order to help the examiners to understand the technical features, contents and advantages of the present invention and the effects that can be achieved, this creation is hereby combined with the accompanying drawings and described in detail as follows in the form of embodiment. The subject matter is only for the purpose of illustrating and assisting the description, not necessarily after the implementation of the present invention. The actual proportion and precise configuration, so the proportion and configuration relationship of the attached diagram should not be interpreted or limited to the scope of rights of this creation in the actual implementation.

Please refer to FIG. 2 , which is a schematic diagram of the metal carrier of the present invention. The metal carrier 2 of the present invention comprises: a base layer 21 , a first metal layer 22 , a second metal layer 23 and a third metal layer 24 , wherein the first metal layer 22 is provided on one side of the base layer 21 , and the second metal layer 23 is provided on one side of the base layer 21 . On one side of the first metal layer 21, the third metal layer 24 is provided on one side of the second metal layer 23. In the embodiment of the present invention, the base layer 21 is a polymer carrier with heat resistance above 220°C, and the base layer 21 has a thickness of Polyimide (P.I, Polyimide) between 25-50 μm, which can withstand the high temperature environment in the hot rolling process.

In the embodiment of the present invention, the first metal layer 22 and the second metal layer 23 are both copper, wherein the thickness of the first metal layer 22 is 80-100 nm, the thickness of the second metal layer 23 is 2-5 μm, and The peel strength between the first metal layer 22 and the second metal layer 23 is 0.5 to 1 kgf/cm. The user can use the equipment to separate the first metal layer 22 from the second metal layer 23 to separate the base layer 21 from the second metal layer 23. The metal layer 23 is separated.

In the embodiment of the present invention, the thickness of the third metal layer 24 is 20-500 nm, and the material of the third metal layer 24 is one or both of molybdenum-niobium alloy, molybdenum-tungsten alloy, molybdenum-tantalum alloy, and molybdenum-titanium alloy. One side of the third metal layer 24 is a rough surface 241 with an arithmetic mean roughness (Ra) of 20-500 nm. Users can use polyimide (P.I, Polyimide), polyterephthalene An insulating substrate such as polyethylene terephthalate (P.E.T) or film (Prepreg, P.P) faces the rough surface 241 and is pressed to combine the metal carrier 2 with the insulating substrate.

Please refer to FIGS. 3-5 , which are the flow chart of the application of the metal carrier in the present invention to the fabrication of the thin film structure, the semi-finished product with the metal carrier and the schematic diagram of the thin film structure, respectively. The application of the metal carrier of the present invention is to manufacture the thin film structure 5, and the manufacturing method includes: S301: Place the film 45 (Prepreg, P.P) on the rough surface of the third metal layer 44, and combine the two to form a thin-film circuit board semi-finished product 4 by a hot rolling process above 220°C; S302: Place the base layer of the semi-finished product 4 41 is separated from the first metal layer 42 and the second metal layer 43, and the base layer 41 is separated from the metal carrier 4 to form a thin film structure 5; in the example of the present invention, the thickness of the base layer 41 is 25 μm, and the first metal layer The thickness of 42 is 80 nm, the thickness of the second metal layer 43 is 3 μm, the thickness of the third metal layer 44 is 250 nm, and the thickness of the film (Prepreg, P.P) is 40-100 μm.

Please refer to FIG. 5 , which is a schematic diagram of the thin film structure of the present invention. The film structure 5 of the present invention includes an adhesive layer 51, a seed layer 52 and a metal layer 53, wherein the adhesive layer 51 is a film (Prepreg, P.P), the seed layer 52 is a molybdenum-niobium alloy, and the metal layer 53 is copper. When the copper chloride-based etchant is used to etch the thin film circuit, the metal layer 53 and the seed layer 52 can be etched and cleaned without using other types of etchants, so as to simplify the etching process and reduce the cost of etching equipment and raw materials. .

Please refer to FIG. 6 , which is a flow chart of the manufacturing method of the metal carrier of the present invention. The manufacturing method of the metal carrier of the present invention includes: S601: providing a polyimide (P.I, Polyimide) as a base layer; S602: sputtering a layer of 80nm copper on the base layer to form a first metal layer; S603: in On the first metal layer, a layer of copper with a thickness of 2-5 μm is electroplated with the chemical wet process as described in the Republic of China Patent No. I589202 to form a second metal layer; S604: Sputter a layer of 300nm on the second metal layer The third metal layer is formed by roughening the molybdenum-niobium alloy; wherein, when the target is bombarded in the sputtering process, the third metal layer is also bombarded, so a roughened structure of the third metal layer can be formed.

Among them, the manufacturing method with metal carrier of the present invention forms ultra-thin copper foil by chemical wet process. Therefore, compared with the hot rolling process of the prior art, the chemical wet process has better controllability for the thickness of copper foil, and the chemical wet process The production line is also relatively simple, without the need for a production line of several kilometers, reducing production risks, reducing manufacturing costs, and increasing process yield.

2: with metal carrier

21: Base Layer

22: The first metal layer

23: Second metal layer

24: The third metal layer

241: Rough surface

Claims (8)

A metal carrier, comprising: a base layer, the base layer is a heat-resistant carrier; a first metal layer, disposed on one side of the base layer; a second metal layer, disposed on one side of the first metal layer; and a A third metal layer is disposed on one side of the second metal layer; wherein, the first metal layer and the second metal layer have peelability; wherein, one side of the third metal layer is a rough surface, and The material of the third metal layer is an alloy containing molybdenum; wherein, the first metal layer and the second metal layer are of the same metal, and the peel strength between the first metal layer and the second metal layer is 0.5 to 3kgf /cm; wherein, the arithmetic mean roughness (Ra) of the rough surface is 20-500 nm. The metal carrier according to claim 1, wherein the heat-resistant temperature of the base layer is above 220°C. The metal-attached carrier according to claim 1, wherein the base layer is polyimide. The metal-attached carrier according to claim 1, wherein the molybdenum-containing alloy is one of molybdenum and niobium, tungsten, tantalum, or titanium or a combination of two or more of them. A method for manufacturing a metal carrier, comprising the steps of: providing a base layer; plating a metal on the base layer by a physical process to form a first metal layer; plating a metal on the first metal layer by a chemical process to form the second metal layer; A molybdenum-containing alloy is plated on the second metal layer by a physical process to form a third metal layer and a rough surface on one side of the third metal layer; wherein the first metal layer and the second metal layer are of the same metal , the peel strength between the first metal layer and the second metal layer is 0.5 to 3 kgf/cm; wherein, the arithmetic mean roughness (Ra) of the rough surface is 20-500 nm. The method for manufacturing a metal carrier according to claim 5, wherein the physical process is a sputtering process. The method for manufacturing a metal carrier according to claim 5, wherein the chemical process is an electroplating process. The manufacturing method of the metal carrier according to claim 5, wherein the chemical process is a chemical wet process.

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