CN212393046U

CN212393046U - Flexible circuit board and semiconductor packaging structure

Info

Publication number: CN212393046U
Application number: CN202021452593.2U
Authority: CN
Inventors: 马菲菲; 高文刚
Original assignee: Goertek Optical Technology Co Ltd
Current assignee: Goertek Optical Technology Co Ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2021-01-22
Anticipated expiration: 2030-07-21

Abstract

The utility model discloses a flexible circuit board and semiconductor package structure, wherein, flexible circuit board includes: a substrate formed with a first pad; the supporting part, the supporting part is located the base plate is carried on the back and is kept away from one side of first pad, the supporting part with first pad sets up relatively, the supporting part is including setting gradually first insulation layer, first copper foil layer and first solder mask on the base plate, first copper foil layer is formed with the second pad, first solder mask is windowed and is exposed the second pad. The utility model discloses a hardness can be strengthened to the supporting part, makes things convenient for the SMT operation, can paste dress electronic component again at this supporting part, realizes that the corresponding both sides face of base plate pastes dress simultaneously, has reduced flexible circuit board's length, has correspondingly reduced semiconductor packaging structure's size, satisfies the miniaturized demand of electronic product.

Description

Flexible circuit board and semiconductor packaging structure

Technical Field

The utility model relates to a circuit board technical field, concretely relates to flexible circuit board and semiconductor packaging structure.

Background

With the development of electronic products to be light, thin and small, the upgrading speed is faster and faster, and the functional requirements are more and more abundant, so that the Printed Circuit Board (PCB) used as a support body of electronic components of the electronic products and a carrier for realizing electrical connection of the electronic components is also more and more demanding, the size of the printed circuit board is smaller and more, and the density is higher and more. In order to meet the requirements of miniaturization and complex functions of products, the flexible circuit board has good bending property, so that the flexible circuit board is more and more widely applied to circuit products. A Flexible Printed Circuit (FPC) is a highly reliable and excellent Flexible Printed Circuit board made of a polyimide or polyester film as a base material. Because the flexible circuit board has good flexibility, the back of the component placement area needs to be provided with a reinforcing support to improve the hardness of the component placement area, so that the Surface Mounted Technology (SMT) operation is facilitated. However, with the development of miniaturization of electronic products, the flexible printed circuit board is made smaller and smaller, and the structural design of the flexible printed circuit board cannot meet the requirement of miniaturization of electronic products.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a flexible circuit board and semiconductor packaging structure aims at improving the problem that present flexible circuit board can't satisfy the miniaturized demand of electronic product.

In order to achieve the above object, the present invention provides a flexible circuit board, including:

a substrate formed with a first pad;

the supporting part, the supporting part is located the base plate is carried on the back and is kept away from one side of first pad, the supporting part with first pad sets up relatively, the supporting part is including setting gradually first insulation layer, first copper foil layer and first solder mask on the base plate, first copper foil layer is formed with the second pad, first solder mask is windowed and is exposed the second pad.

Preferably, the substrate includes a second insulating layer, a second copper foil layer and a second solder resist layer, which are sequentially stacked, and the first insulating layer is disposed on the second solder resist layer.

Preferably, the base plate still includes the third copper foil layer and cover in the third solder mask on third copper foil layer, the third copper foil layer with the second copper foil layer is located respectively the both sides that the second insulating layer is relative, the third copper foil layer is formed with first pad, third solder mask opens the window and exposes first pad.

Preferably, the hardness of the first insulating layer is greater than the hardness of the second insulating layer.

Preferably, the insulating material of the first insulating layer is polypropylene or an FR-4 composite material, and the insulating material of the second insulating layer is a polyimide or polyester material.

Preferably, the second copper foil layer is formed with a third pad, the second solder mask layer is windowed and exposed to the third pad, the substrate further comprises a reinforcing plate arranged on the third solder mask layer, and the reinforcing plate is arranged opposite to the third pad.

Preferably, the first pad is used for connecting with a main chip, the second pad is used for connecting with a storage device, and the third pad is used for connecting with a connector.

Preferably, the thickness of the first insulating layer is greater than or equal to the thickness of the second insulating layer.

Furthermore, the utility model also provides a semiconductor package structure, including the aforesaid flexible circuit board.

The technical scheme of the utility model in, flexible circuit board includes base plate and supporting part, and the base plate is formed with first pad, and the supporting part is located the base plate separates mutually one side of first pad, the supporting part with first pad sets up relatively, and the supporting part is including setting gradually first insulation layer, first copper foil layer and first solder mask on the base plate, first copper foil layer is formed with the second pad, first solder mask is windowed and is exposed the second pad. The utility model discloses a hardness can be strengthened to the supporting part, makes things convenient for the SMT operation, can paste dress electronic component again at this supporting part, realizes that the corresponding both sides face of base plate pastes dress simultaneously, has reduced flexible circuit board's length, has correspondingly reduced semiconductor packaging structure's size, satisfies the miniaturized demand of electronic product.

Drawings

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

Fig. 1 is a schematic diagram of a flexible circuit board according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a prior art flexible circuit board.

The reference numbers illustrate:

1	substrate	11	A second insulating layer
				12	Second copper foil layer	121	Third bonding pad
13	Third copper foil layer	131	First bonding pad
				14	Second solder resist layer	15	Third solder resist layer
16	Reinforcement plate	2	Supporting part
				21	A first insulating layer	22	First copper foil layer
221	Second bonding pad	23	First solder resist layer
				3	Main chip	4	Memory device
5	Connector with a locking member

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

In addition, the technical solutions between the embodiments of the present invention can be combined with each other, but it is necessary to be able to be realized by a person having ordinary skill in the art as a basis, and when the technical solutions are contradictory or cannot be realized, the combination of such technical solutions should be considered to be absent, and is not within the protection scope of the present invention.

As shown in fig. 1, the utility model provides a flexible circuit board, include:

a substrate 1, the substrate 1 having a first pad 131 formed thereon;

the supporting portion 2 is located on one side of the substrate 1 away from the first pad 131, the supporting portion 2 is opposite to the first pad 131, the supporting portion 2 includes a first insulating layer 21, a first copper foil layer 22 and a first solder resist layer 23 which are sequentially arranged on the substrate 1, the first copper foil layer 22 is formed with a second pad 221, and the first solder resist layer 23 is windowed to expose the second pad 221.

In the conventional flexible circuit board, as shown in fig. 2, a reinforcing plate 16 is generally disposed on one side of the substrate 1 away from the first pad 131 for enhancing the hardness, so as to facilitate the SMT operation, the utility model discloses the reinforcing plate 16 at this position is replaced by the supporting portion 2, the first copper foil layer 22 of the supporting portion 2 is used for forming the second pad 221, the first pad 131 and the second pad 221 can both be used for mounting electronic components, the first solder mask layer 23 is used for covering the first copper foil layer 22 for protection, but the first pad 131 is windowed, so as to expose the first pad 131. First insulation layer 21, first copper foil layer 22 and first solder mask 23 have certain thickness and hardness, can replace the reinforcing plate, consequently the utility model discloses a supporting part 2 can strengthen hardness, makes things convenient for the SMT operation, again can paste electronic component at this supporting part 2, realizes that 1 corresponding both sides face of base plate pastes the dress simultaneously, has reduced flexible circuit board's length, has correspondingly reduced semiconductor packaging structure's size, satisfies the miniaturized demand of electronic product.

Specifically, the substrate 1 includes a second insulating layer 11, a second copper foil layer 12, and a second solder resist layer 14, which are sequentially stacked, and a first insulating layer 21 is provided on the second solder resist layer 14. The second insulating layer 11 is an insulating film and forms a base layer of a circuit, the adhesive bonds the second copper foil layer 12 to the second insulating layer 11, the second copper foil layer 12 can be formed by electrodeposition or plating, and the second copper foil layer 12 forms a conductive layer. The second solder mask layer 14 consists of a solder resist material which is applied by a liquid wet process or a dry film stack, the second solder mask layer 14 being used for a protective covering to insulate the circuit from dust and moisture.

More specifically, the substrate 1 further includes a third copper foil layer 13 and a third solder resist layer 15 covering the third copper foil layer 13, the third copper foil layer 13 and the second copper foil layer 12 are respectively disposed on two opposite sides of the second insulating layer 11, the third copper foil layer 13 is formed with a first pad 131, and the third solder resist layer 15 is windowed to expose the first pad 131. The second insulating layer 11 is provided between the second copper foil layer 12 and the third copper foil layer 13, forming the double-sided copper-clad substrate 1. More pads may also be formed on the third copper foil layer 13 for connecting more electronic components.

Preferably, the hardness of the first insulating layer 21 is greater than that of the second insulating layer 11, the second insulating layer 11 is generally thin and flexible, so that the substrate 1 can be bent, and the hardness of the first insulating layer 21 is greater than the thickness of the second insulating layer 11, so that the hardness of the first pad 131 and the second pad 221 is sufficiently large, which facilitates SMT operation and reduces the size of the flexible circuit board.

More preferably, the insulating material of the first insulating layer 21 is polypropylene or an FR-4 composite material, and the insulating material of the second insulating layer 11 is a polyimide or polyester material. Polypropylene (PP) is a thermoplastic synthetic resin with excellent performance, is colorless semitransparent thermoplastic light general-purpose plastic, and has chemical resistance, heat resistance, electrical insulation, high-strength mechanical properties, good high-wear-resistance processing performance and the like. FR-4 is a code of a flame-resistant material grade, which means a material specification that a resin material must be self-extinguished after burning, and it is not a material name but a material grade, so that there are very many kinds of FR-4 grade materials used for general circuit boards, but most are composite materials made of so-called tetra-functional (terra-functional) epoxy resin plus Filler (Filler) and glass fiber. FR-4epoxy glass cloth laminates, depending on the application used, are commonly referred to in the industry as: FR-4Epoxy Glass wall, an insulating plate, an Epoxy resin plate, a brominated Epoxy resin plate, FR-4, a Glass fiber plate, an FR-4 reinforcing plate, an FPC reinforcing plate 16, a flexible circuit board reinforcing plate 16, an FR-4Epoxy resin plate, a flame-retardant insulating plate, an FR-4 laminated plate, an Epoxy plate, an FR-4 light plate, an FR-4 Glass fiber plate, an Epoxy Glass Cloth laminated plate and a circuit board drilling base plate. The FR-4 material has stable electrical insulation performance, good flatness, smooth surface, no pit and standard thickness tolerance, and is suitable for products with high-performance electronic insulation requirements.

The polyimide material has non-flammability, stable geometric dimension, higher tear strength and the ability to withstand soldering temperatures. Polyester, also known as polyethylene terephthalate (PET), has physical properties similar to polyimide, has a low dielectric constant, absorbs little moisture, but does not resist high temperature. Polyesters have a melting point of 250 ℃ and a glass transition temperature (Tg) of 80 ℃, which limits their use in applications requiring a large number of end welds. In low temperature applications, they exhibit rigidity. Nevertheless, they are suitable for use on products such as telephones and other products that do not require exposure to harsh environments.

Further, the second copper foil layer 12 is formed with a third pad 121, the second solder resist layer 14 is windowed to expose the third pad 121, the substrate 1 further includes a reinforcing plate 16 disposed on the third solder resist layer 15, and the reinforcing plate 16 is disposed opposite to the third pad 121. In the prior art, as shown in fig. 2, a first pad 131 and a second pad 221 are respectively disposed on the same side of a substrate 1, a third pad 121 is disposed on the other side of the substrate 1, and a reinforcing plate 16 is disposed on the other side of the substrate 1 opposite to each pad, so that due to requirements on product functions, structural limitations, and the like, a front-back reinforcing distance is short; or in order to improve the efficiency, the printed circuit board is operated in a jointed board mode during board manufacturing or SMT (surface mount technology) pasting, and the condition that the reinforcement distance of the front side and the back side is short exists, namely the d1 size is small, so that the SMT operation is difficult to realize when the d1 is smaller than 0.6 mm. In the present embodiment, as shown in fig. 1, the second pad 221 is disposed on the opposite side of the first pad 131, the reinforcing plates 16 corresponding to the first pad 131 and the second pad 221 are omitted, the distance between the reinforcing plate 16 of the third pad 121 and the support portion 2 is increased, the requirement of product miniaturization is satisfied, and the problem of SMT is solved.

Of course, in other embodiments, the third pad 121 may be disposed on the same side as the first pad 131, and the reinforcing plate 16 of the third pad 121 may be disposed on the same side as the second pad 221, so that the positions and the number of the support portion 2, the pads, and the reinforcing plate 16 may be adjusted according to the functions and structures of the product, and will not be described herein again.

The first pads 131 of the present embodiment are used for connection with the main chip 3, the second pads 221 are used for connection with the memory device 4, and the third pads 121 are used for connection with the connector 5. The storage device 4 may be a flash storage device 4, and of course, the first pads 131, the second pads 221 and the third pads 121 of the present invention are not limited to be connected to the above-mentioned electronic components, the connected electronic components may be selected according to specific needs, and the number and positions of the first pads 131, the second pads 221 and the third pads 121 may also be adjusted according to needs.

Further, the thickness of the first insulating layer 21 is greater than or equal to the thickness of the second insulating layer 11, since the second insulating layer 11 is generally designed to be thinner to ensure the flexibility of the substrate 1, and the first insulating layer 21 of the supporting portion 2 is designed to be thicker, so that the hardness of the supporting portion 2 can be improved, and the SMT operation is facilitated. However, in other embodiments, the thickness of the first insulating layer 21 may be designed to be smaller than the thickness of the second insulating layer 11, but the hardness is greater than that of the second insulating layer 11, which also facilitates SMT jobs.

Furthermore, the utility model also provides a semiconductor package structure, including foretell flexible circuit board. The specific structure of the flexible circuit board refers to the above embodiments, and since the semiconductor package structure adopts all technical solutions of all the above embodiments, at least all the beneficial effects brought by the technical solutions of the above embodiments are achieved, and no further description is given here. The semiconductor packaging structure can be applied to miniature projectors, AR and VR products and wearable electronic products. The utility model discloses from flexible circuit board's design angle, provide a novel flexible circuit board that adapts to the miniaturized requirement of product, the advantage of maximize performance flexible circuit board can not bring the challenge to the production in the factory again.

The above is only the preferred embodiment of the present invention, not so limiting the patent scope of the present invention, all of which are under the concept of the present invention, the equivalent transformation made by the specification or direct/indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A flexible circuit board, comprising:

a substrate formed with a first pad;

2. The flexible circuit board according to claim 1, wherein the substrate includes a second insulating layer, a second copper foil layer, and a second solder resist layer, which are sequentially stacked, the first insulating layer being provided on the second solder resist layer.

3. The flexible circuit board of claim 2, wherein the substrate further comprises a third copper foil layer and a third solder mask layer covering the third copper foil layer, the third copper foil layer and the second copper foil layer are respectively disposed on two opposite sides of the second insulating layer, the third copper foil layer is formed with the first pad, and the third solder mask layer is opened to expose the first pad.

4. The flexible circuit board of claim 3, wherein a hardness of the first insulating layer is greater than a hardness of the second insulating layer.

5. The flexible circuit board of claim 4, wherein the insulating material of the first insulating layer is polypropylene or an FR-4 composite material, and the insulating material of the second insulating layer is a polyimide or a polyester material.

6. The flexible circuit board of claim 3, wherein the second copper foil layer is formed with a third pad, the second solder mask is windowed to expose the third pad, the substrate further comprises a stiffener disposed on the third solder mask, the stiffener being disposed opposite the third pad.

7. The flexible circuit board of claim 6, wherein the first pads are for connection to a main chip, the second pads are for connection to a memory device, and the third pads are for connection to a connector.

8. The flexible circuit board according to any one of claims 3 to 7, wherein a thickness of the first insulating layer is greater than or equal to a thickness of the second insulating layer.

9. A semiconductor package structure, comprising the flexible circuit board according to any one of claims 1 to 8.