TWI613948B - Multilayer rigid flexible substrate and method of manufacturing same - Google Patents

Abstract

A combination of a low-elasticity prepreg and a flexible substrate provides a highly reliable multilayer rigid flexible substrate and a method for manufacturing the same.

The multilayer rigid flexible substrate according to the embodiment is a multilayer flexible flexible substrate in which a plurality of flexible substrates are bonded and a plurality of flexible substrates are bonded together, having rigid portions on both sides, and a curved portion between the rigid portions. It is characterized in that the flexible substrate having an inner layer formed in the bent portion is bonded to a low elasticity prepreg.

Description

Multi-layer rigid flexible substrate and manufacturing method thereof

Embodiments of the present invention relate to a multilayer rigid flexible substrate and a method for manufacturing the same.

There is a rigid flexible substrate in which a flexible substrate using a bending material (for example, polyimide) is sandwiched between rigid substrates having a hard material such as glass epoxy on both sides. If the rigid flexible substrate is a rigid substrate, it has the same rigidity as a general substrate, so it has an excellent effect of component assembly. If it is a flexible substrate, it has flexibility, so it has the inside of an electronic device. The effect of the connection.

In the conventional method for manufacturing a multilayer rigid flexible substrate, since a polyimide material is used in the bent portion, if it has a layer structure that can bend all layers (the number of layers in the rigid portion and the bent portion is the same), There are the following issues.

(1) Decrease in bendability due to adhesion of polyimide

(2) Increased risk of interlayer peeling

(3) Degradation of through-hole quality caused by adhesive (polyimide coating)

(4) Increase in the number of manufacturing processes

In addition, the prior art of a multilayer rigid flexible substrate includes International Publication WO2009 / 119027, Japanese Patent Publication, Japanese Patent Laid-Open No. 2986-324406, and Japanese Patent No. 5486020.

The problem to be solved by the invention is to solve the above-mentioned conventional problems, and to provide a high-reliability multilayer rigid flexible substrate and a method for manufacturing the same by combining a low-elasticity prepreg and a flexible substrate.

The multilayer rigid flexible substrate of the embodiment has the following characteristics.

The multilayer rigid flexible substrate is a multilayer flexible flexible substrate in which a plurality of flexible substrates are bonded to each other. The multilayer flexible flexible substrate has rigid portions on both sides and a curved portion between the rigid portions. : The flexible substrate having an inner layer formed in the bent portion is bonded to a low elasticity prepreg.

In addition, the manufacturing method of the multilayer rigid flexible substrate according to the embodiment is characterized by having a process of forming an inner layer pattern of all the flexible substrates, and performing a process of sandwiching a low elasticity prepreg between the plurality of flexible substrates. A process of laminating and forming a multilayer flexible substrate; and a process of bonding a rigid portion of a plurality of the aforementioned multilayer flexible substrates with a highly elastic prepreg sandwiched therebetween.

According to the multilayer rigid flexible substrate of this embodiment and the manufacturing method thereof, the flexibility of the bent portion is protected by a low-elastic prepreg. The substrate can provide a bent portion with high rigidity and excellent electrical characteristics.

10, 20‧‧‧ rigid part

30‧‧‧ Bend

40‧‧‧ flexible substrate

45‧‧‧Low elasticity prepreg

50‧‧‧The first multilayer flexible substrate

60‧‧‧Second multilayer flexible substrate

70‧‧‧ 3rd multilayer flexible substrate

80a ~ 80d‧‧‧Highly elastic prepreg

85a ~ 85d‧‧‧ copper foil

95a ~ 95d‧‧‧Conductor

110a ~ 110d‧‧‧solder resist

100, 200‧‧‧ multilayer rigid flexible substrate

210, 220‧‧‧ Low elasticity prepreg

500‧‧‧The first electronic device

600‧‧‧ 2nd electronic device

FIG. 1 is a diagram showing a configuration of a multilayer rigid flexible substrate according to the first embodiment.

FIG. 2 is a diagram showing a modified example of the multilayer rigid flexible substrate according to the first embodiment.

FIG. 3 is a diagram showing a configuration of a multilayer rigid flexible substrate according to a second embodiment.

FIG. 4 is a diagram showing a configuration of a flexible substrate of an inner layer in the first embodiment and the second embodiment.

FIG. 5 is a diagram showing a configuration of a multilayer flexible substrate of an inner layer in the first embodiment and the second embodiment.

6 is a flowchart showing a manufacturing process of a multilayer rigid flexible substrate according to the first embodiment and the second embodiment.

FIG. 7 is a diagram showing the configuration of an 18-layer rigid flexible substrate according to the present invention.

FIG. 8 is a diagram showing a configuration of a 16-layer rigid flexible substrate according to the present invention.

FIG. 9 is a diagram showing the structure of a 12-layer rigid flexible substrate according to the present invention.

FIG. 10 is a diagram showing a configuration of an eight-layer rigid flexible substrate according to the present invention.

FIG. 11 is a diagram showing the configuration of a six-layer standard rigid flexible substrate according to the present invention.

FIG. 12 is a diagram showing a device connection example of the multilayer rigid flexible substrate according to the embodiment.

Hereinafter, a multilayer rigid flexible substrate according to an embodiment of the present invention will be described with reference to the drawings.

(First Embodiment)

FIG. 1 is a diagram showing a configuration of a multilayer rigid flexible substrate according to the first embodiment.

In FIG. 1, the multilayer rigid flexible substrate 100 includes rigid portions 10 and 20 and a bending portion 30 provided between the rigid portions 10 and 20. The multilayer rigid flexible substrate 100 is one in which a plurality of layers of flexible substrates are laminated and bonded by pressing. Each multilayer flexible substrate layer has a structure in which both sides of a plurality of flexible substrates are bonded and protected by a low-elastic prepreg. Here, each flexible substrate is formed as a substrate with two surfaces and two layers, but it may be a single surface and a single layer. In FIG. 1, the thick-frame block represents a two-layer flexible substrate 40. The hatched portions in the vertical direction indicate the low-elasticity prepreg 45.

In addition, FIG. 1 shows a diagram in which three multilayer flexible substrate layers 50, 60, and 70 are laminated. The three multilayer flexible substrate layers 50, 60, and 70 are in the rigid portions 10 and 20, and the highly elastic prepreg 80a, 80b, 80c, 80d are joined. Among them, through holes (not shown) are provided in the rigid portions 10 and 20, and the flexible substrates of the respective layers are electrically connected.

Fig. 2 shows a modification of the first embodiment. In the multilayer rigid flexible substrate of FIG. 2, copper foils 85 a, 85 b, 85 c, and 85 c are bonded to the low-elasticity prepreg 45 disposed on the surface layers (front and back surfaces) of the rigid portions 10 and 20. Thereby, a conductive layer is formed by the copper foils 85a, 85b, 85c, and 85c on the low elasticity prepreg 45.

(Second Embodiment)

FIG. 3 is a diagram showing a configuration of a multilayer rigid flexible substrate according to a second embodiment.

In FIG. 3, the multilayer rigid flexible substrate 200 is configured like the first embodiment, and includes rigid portions 10 and 20 and a bending portion 30 provided between the rigid portions 10 and 20. The multilayer rigid flexible substrate 200 is one in which a plurality of layers of flexible substrates are laminated and bonded by punching. Each multilayer flexible substrate layer has a structure in which both sides of a plurality of flexible substrates are bonded and protected by a low-elastic prepreg. For example, regarding the laminated structure formed by three multilayer flexible substrate layers 50, 60, and 70, and the three multilayer flexible substrate layers 50, 60, and 70 in the rigid portions 10, 20 are preliminarily prepared with high elasticity. The dipping materials 80a, 80b, 80c, and 80d are also joined to each other in the same manner as in the first embodiment.

The difference from the first embodiment is that the exposed surfaces of the surface layers (front and back surfaces) are not low-elastic prepregs as in the first embodiment, but are formed as conductors of the flexible substrates 90a and 90b. In addition, the surface The guides of the bent portions 30 of the flexible substrates 90a and 90b are removed. The conductors 95a, 95b, 95c, and 95d of the rigid portions 10 and 20 are protected by solder resists (SR) 110a, 110b, 110c, and 110d.

FIG. 4 is a diagram showing a configuration of a flexible substrate of an inner layer (except for a flexible substrate whose surface layer is exposed) in the first embodiment and the second embodiment. Both sides of the flexible substrate 200 in the inner layer are bonded to the low-elasticity prepregs 210 and 220 and protected.

The low-elasticity prepregs 210 and 220 are doped with glass cloth and are flexible multilayer materials with low elasticity. The elastic modulus is preferably 10 Gpa or less. In addition, the thermal expansion coefficient is preferably 10 ppm / ° C.

FIG. 5 is an enlarged view of a laminated state of the multilayer flexible substrate layers 50, 60, and 70 shown in the first embodiment. Multi-layer flexible substrate layers 50, 60, and 70 are composed of a low-elastic prepreg-2 layers of flexible parts-a low-elastic prepreg-2 layers of flexible parts-a low-elastic prepreg-2 layers of flexible parts- Six layers of flexible substrates laminated in order of low elasticity prepreg. Next, as shown in FIG. 1, the interlayers of the multilayer flexible substrate layers 50, 60, and 70 are joined by the highly elastic prepregs 80 a to 80 d in which only the bent portion 30 is subjected to window processing.

The highly elastic prepreg 80a ~ 80d is preferably an elasticity of 18 to 25 Gpa. In addition, the thermal expansion coefficient is preferably 13 to 16 ppm / ° C.

6 is a flowchart showing a manufacturing process of a multilayer rigid flexible substrate according to the first embodiment and the second embodiment.

First, the inner layer patterns of all two layers of flexible substrates (18 layers in FIG. 1) are formed (step S100).

Next, both surfaces (conductors) of each flexible substrate of the multilayer flexible substrate layers 50, 60, and 70 are protected by a low-elasticity prepreg (reference numerals 210 and 220 in FIG. 4). Next, if a copper foil is placed on the low-elasticity prepregs of the rigid portions 10 and 20, the copper foils 85a to 85d shown in FIG. 2 are bonded. When the surface layers (symbols 90a and 90b in FIG. 3) of the multilayer flexible substrate layers 50 and 70 are formed as flexible substrates, the conductors in the bent portion are removed and the conductors in the rigid portion are removed (symbols 95a to 95d in FIG. 2). It is protected with solder resist (symbols 110a to 110b in Figure 2). Next, a plurality of flexible substrate layers 50, 60, and 70 are formed by primary lamination, respectively (step S110).

Finally, the high-elasticity prepregs 80a to 80d that are processed only in the bent portion 30 by double lamination are used to join the rigid portions 10, 20 between the three multilayer flexible substrate layers 50, 60, and 70. (Step S120). Therefore, the rigid portions 10 and 20 are formed as a relatively rigid substrate.

Thereby, the completed multilayer rigid flexible substrate is formed into a shape of the flexible substrate sandwiching the bent portion 30 with a low-elasticity prepreg to protect the flexible substrate. Therefore, if the multilayer rigid flexible substrate is used to connect electronic devices, the bent portion is formed with high rigidity and excellent electrical characteristics such as high frequency.

Among them, the through-hole operation of the rigid portions 10 and 20 and the solder material connection between the substrates are not directly related to the present invention, and are omitted.

Next, various examples of the multilayer rigid flexible substrate manufactured by the first or second embodiment will be described.

FIG. 7 is a diagram showing a configuration of an 18-layer-type multilayer rigid flexible substrate.

In the 18-layer specification, two layers of flexible parts-low-elastic prepreg-2 layers of flexible parts-low-elastic prepreg-2 layers of flexible parts-low-elastic prepreg, forming the first of 6 layers Multi-layer flexible substrate 50.

In addition, a low-elastic prepreg-2 layers of flexible parts-a low-elastic prepreg-2 layers of flexible parts-a low-elastic prepreg-2 layers of a flexible part-low-elastic prepregs to form 6 Layer of the second multilayer flexible substrate 60.

In addition, a low-elasticity prepreg-2 layers of flexible parts-a low-elasticity prepreg-2 layers of flexible parts-a low-elasticity prepreg-2 layers of flexibility are used to form a 6-layer third-layer flexible substrate 70.

Among them, in the surface layer (exposed layer) of the first multilayer flexible substrate 50 and the third multilayer flexible substrate 70, the two-layer flexible exposed-side guide systems of the bent portion 30 are removed, and the rigid portion 10 The exposed conductors 95a to 95d of 20 and 20 are protected by solder resists 110a to 110d.

Next, when the first multi-layer flexible substrate 50, the second multi-layer flexible substrate 60, and the third multi-layer flexible substrate 70 are laminated, the rigid portions 10 and 20 are provided with highly elastic prepregs 80a to 80d. Join. Thereby, the 18-layer rigid flexible substrate with high rigidity in the bent portion can be protected by the low-elasticity prepreg with two layers of flexible inner-layer conductors.

FIG. 8 is a diagram showing a configuration of a multilayer rigid flexible substrate of a 16-layer specification.

In the 16-layer specification, a low-elasticity prepreg material-2 layers of flexible parts-a low-elasticity prepreg material-2 layers of flexible parts-a low-elasticity prepreg material are used to form a five-layered first multilayer flexible substrate 50 .

In addition, with low elasticity prepreg-2 layers of flexible parts-low elasticity Impregnated material-2 layers of flexible member-low elasticity prepreg material-2 layers of flexible member-low elasticity prepreg material, forming a 6-layer second multilayer flexible substrate 60 in the middle portion.

In addition, a low-elasticity prepreg material-2 layers of flexible material-low-elasticity prepreg material-2 layers of flexible material-low-elasticity prepreg material are used to form a third-layer flexible substrate 70 of five layers.

Among them, in the surface layer (exposed layer) of the first multilayer flexible substrate and the third multilayer flexible substrate, copper foils 85a to 85d are bonded to the low-elasticity prepreg material on the surface where the rigid portions 10 and 20 are exposed. Form a conductor.

Next, when the first multi-layer flexible substrate 50, the second multi-layer flexible substrate 60, and the third multi-layer flexible substrate 70 are laminated, the rigid portions 10 and 20 are provided with highly elastic prepregs 80a to 80d. Join. Thereby, a 16-layer rigid flexible substrate with high rigidity in the bent portion can be protected by the low-elasticity prepreg and the two-layer flexible inner-layer conductor.

FIG. 9 is a diagram showing a configuration of a multilayer rigid flexible substrate of a 12-layer specification.

In the 12-layer specification, two layers of flexible members-low elasticity prepreg material-2 layers of flexible members-low elasticity prepreg material are used to form a four-layer first multilayer flexible substrate 50.

In addition, the second multilayer flexible substrate 60 having four layers in the middle portion is formed by the low-elastic prepreg material-2 layers of flexible material-low-elastic prepreg material-2 layers of flexible material-low elastic prepreg material.

In addition, the low-elasticity prepreg material-2 layer flexible member-the low-elasticity prepreg material-2 layer flexibility is used to form a third layer of the third multilayer flexible substrate 70.

Among them, the first multilayer flexible substrate 50 and the third multilayer In the surface layer (exposed layer) of the flexible substrate 70, two layers of the flexible exposed side guides of the bent portion 30 are removed, and the exposed conductors 95a to 95d of the rigid portions 10 and 20 are provided with solder resists 110a to 110d. protection.

Next, when the first multi-layer flexible substrate 50, the second multi-layer flexible substrate 60, and the third multi-layer flexible substrate 70 are laminated, the rigid portions 10 and 20 are provided with highly elastic prepregs 80a to 80d. Join. This makes it possible to protect the two-layer flexible inner-layer conductor with the low-elasticity prepreg and the 12-layer rigid flexible substrate with high rigidity at the bent portion.

FIG. 10 is a diagram showing a configuration of a multilayer rigid flexible substrate of an eight-layer specification.

In the eight-layer specification, two layers of flexible members-low elasticity prepreg material-2 layers of flexible members-low elasticity prepreg material are used to form a four-layer first multilayer flexible substrate 50.

In addition, the low-elasticity prepreg material-2 layer flexible member-the low-elasticity prepreg material-2 layer flexibility is used to form a second-layer flexible substrate 60 of four layers.

Among the surface layers (exposed layers) of the first multi-layer flexible substrate 50 and the second multi-layer flexible substrate 60, the two-layer flexible exposed-side guides of the bent portion 30 are removed, and the rigid portions 10, The exposed conductors 95a to 95d of 20 are protected by solder resists 110a to 110d.

Next, when the first multilayer flexible substrate 50 and the second multilayer flexible substrate 60 are laminated, the rigid portions 10 and 20 are joined by highly elastic prepregs 80a and 80b. This makes it possible to protect the two-layer flexible inner-layer conductor with the low-elasticity prepreg, and the eight-layer rigid flexible substrate having high rigidity at the bent portion.

FIG. 11 is a diagram showing a configuration of a multilayer rigid flexible substrate of a six-layer specification.

In the six-layer specification, a three-layered first multilayer flexible substrate 50 is formed of a low-elastic prepreg, two layers of flexible parts, and a low-elastic prepreg.

In addition, a two-layer flexible substrate 60 of three layers is formed from the low-elasticity prepreg material-2 layers of flexible members-low-elasticity prepreg material.

Among them, in the surface layer (exposed layer) of the first multilayer flexible substrate and the third multilayer flexible substrate, copper foils 85a to 85d are bonded to the low-elasticity prepreg material on the surface exposing the rigid portions 10 and 20, Form a conductor.

Next, when the first multilayer flexible substrate 50 and the second multilayer flexible substrate 60 are laminated, the rigid portions 10 and 20 are joined by highly elastic prepregs 80a and 80b. Thereby, it is possible to protect the two-layer flexible inner-layer conductor with the low-elasticity prepreg and the six-layer rigid flexible substrate with high rigidity at the bent portion.

FIG. 12 is a diagram showing an example of connection between devices using 18 to 6 layers of rigid flexible substrates shown in FIGS. 7 to 11. As described above, by using the multilayer rigid flexible substrate of the embodiment, one of the rigid portions is connected to the first electronic device 500, and the other of the rigid portions is bent by 90 degrees, for example, so that the second electronic device can be connected to the second electronic device. 600-phase connection.

According to the multilayer rigid flexible substrate of the embodiment, the rigidity of the bent portion is high and the electrical characteristics are excellent. In addition, the contact strength between the rigid portion and the curved portion is high, and it is possible to prevent interlayer peeling (delamination, etc.) from occurring. In addition, the same through-hole reliability as that of a rigid substrate can be obtained. In addition, it can be manufactured on the same basis as a rigid substrate. Manufacturing process can be used to simplify the manufacturing process.

The embodiments of the present invention have been described above, but these embodiments are given as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and modifications are included in the scope or gist of the invention, and are included in the invention described in the scope of patent application and its equivalent scope.

10, 20‧‧‧ rigid part

30‧‧‧ Bend

40‧‧‧ flexible substrate

45‧‧‧Low elasticity prepreg

50‧‧‧The first multilayer flexible substrate

60‧‧‧Second multilayer flexible substrate

70‧‧‧ 3rd multilayer flexible substrate

80a ~ 80d‧‧‧Highly elastic prepreg

100‧‧‧Multi-layer rigid flexible substrate

Claims (12)

A multilayer rigid flexible substrate comprising a multilayer flexible substrate in which a plurality of flexible substrates are bonded to a plurality of layers, and has a rigid portion in a region including both edge portions and a region between the rigid portions. The multilayer rigid flexible substrate with a curved portion connected to the rigid portion is characterized in that the plurality of two flexible substrates are joined by a low-elastic prepreg, and the multilayer flexible substrate with the rigid portion is laminated. The layers are joined by a highly elastic prepreg. The elastic modulus of the low elastic prepreg is lower than the elastic modulus of the high elastic prepreg. For example, the multilayer rigid flexible substrate of the first patent application range, wherein the elastic modulus of the aforementioned low-elastic prepreg is 10 Gpa or less, and the elastic modulus of the aforementioned high-elastic prepreg is 18 to 25 Gpa. For example, the multilayer rigid flexible substrate of the first patent application range, wherein the thermal expansion coefficient of the low-elastic prepreg is equal to the thermal expansion coefficient of the multilayer flexible substrate layer of the rigid portion. For example, the multi-layer rigid flexible substrate of claim 3, wherein the thermal expansion coefficient of the aforementioned low elastic prepreg is 10 ppm / ° C, and the thermal expansion coefficient of the aforementioned high elastic prepreg is 13 to 16 ppm / ° C. For example, in the multi-layer rigid flexible substrate of the scope of application for item 1 or 3, the flexible substrate composed of the aforementioned two-layer flexible substrate and the low-elasticity prepreg is included in the rigid portion. Bonded to the aforementioned highly elastic prepreg. If multi-layer rigidity is flexible In the flexible substrate, if the surface layer is the flexible substrate, the guide system of the curved portion on the exposed side is removed, and the guide system of the rigid portion is protected by a protective member. For example, if the multilayer rigid flexible substrate of the first or third aspect of the patent application is applied, if the surface layer is the aforementioned low-elastic prepreg, a copper foil is bonded to the aforementioned low-elastic prepreg of the rigid portion. A method for manufacturing a multilayer rigid flexible substrate is a multilayer flexible substrate in which a plurality of layers of flexible substrates bonded to a plurality of layers are bonded. The multilayer flexible substrate has a rigid portion in a region including both edge portions, and is provided between the rigid portions. A method for manufacturing a multilayer rigid flexible substrate having a curved portion connected to the rigid portion in a region of the method is characterized in that the method includes: laminating a plurality of flexible substrates with a low-elasticity prepreg to form a multilayer multilayer flexible substrate; A process of a flexible substrate; and a process of joining a high-elastic prepreg having an elastic modulus higher than that of the low-elastic prepreg, to a rigid portion of the plurality of multilayer flexible substrates. For example, in the method for manufacturing a multilayer rigid flexible substrate according to item 8 of the application, the thermal expansion coefficient of the low-elastic prepreg is equal to the thermal expansion coefficient of the multilayer flexible substrate layer of the rigid portion. For example, in the method for manufacturing a multilayer rigid flexible substrate of the eighth or ninth scope of the application for a patent, in the aforementioned rigid portion, a flexible substrate composed of the aforementioned two-layer flexible substrate and a low-elastic prepreg. It is connected with the aforementioned highly elastic prepreg material inside. For example, the method for manufacturing a multilayer rigid flexible substrate of the eighth or ninth scope of the patent application, further comprising: if the surface layer is the aforementioned flexible substrate, the guide system of the aforementioned bent portion on the exposed side is removed ; And a process for protecting the conductor of the rigid portion with a protective member. For example, the method for manufacturing a multilayer rigid flexible substrate according to item 8 or item 9 of the patent application scope, further comprising: if the surface layer is the aforementioned low-elastic prepreg, on the aforementioned low-elastic prepreg of the rigid portion Process for bonding copper foil.