CN210156369U

CN210156369U - Side wall copper exposure packaging structure

Info

Publication number: CN210156369U
Application number: CN201921240411.2U
Authority: CN
Inventors: 谭小春; 姚兰忠
Original assignee: Hangzhou Silergy Semiconductor Technology Ltd
Current assignee: Hangzhou Silergy Semiconductor Technology Ltd
Priority date: 2019-08-01
Filing date: 2019-08-01
Publication date: 2020-03-17
Anticipated expiration: 2029-08-01

Abstract

The utility model provides a lateral wall dew copper packaging structure utilizes half to cut, cuts twice cutting process entirely, and the top surface and the at least one side of weld pad all expose in the plastic-sealed body among the lateral wall dew copper packaging structure that forms have enlarged the exposed area of weld pad, increase the contact surface when lateral wall dew copper packaging structure carries out fixed connection with external component, improve weldability and welded reliability to improve the fastness of the two fixed connection, improve product reliability and yield.

Description

Side wall copper exposure packaging structure

Technical Field

The utility model relates to a semiconductor package field especially relates to a lateral wall exposes copper packaging structure.

Background

With the development of electronic products, semiconductor technology has been widely used to manufacture memory, Central Processing Unit (CPU), Liquid Crystal Display (LCD), Light Emitting Diode (LED), laser diode, and other devices or chip sets. Since electronic components such as semiconductor components, micro-electro-mechanical systems (MEMS) or optoelectronic components have minute and fine circuits and structures, in order to prevent dust, acid-base substances, moisture, oxygen, etc. from contaminating or eroding the electronic components, thereby affecting the reliability and lifetime thereof, the related functions of Power Distribution, Signal Distribution, Heat Dissipation, protection and Support, etc. need to be provided for the electronic components by packaging technology.

After the semiconductor chip is packaged to form a package structure, the package structure is connected or assembled with other electrical components according to different use conditions. For example, in some cases, the package structure needs to be fixedly connected to an external member, such as a PCB (Printed Circuit Board), by soldering or the like. The exposed surface of the pin of the existing packaging structure is small, so that when the pin is fixedly connected with an external component through processes such as soldering and the like, the contact surface of soldering tin is small, and the firmness, reliability and yield of fixed connection are affected.

Therefore, a new package structure is needed to overcome the disadvantages of the above package structure.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a lateral wall dew copper packaging structure, its exposed area that can enlarge packaging structure's weld pad increases the contact surface when packaging structure carries out fixed connection with the external component, improves the fastness of the two fixed connection.

In order to realize the above-mentioned purpose, the utility model provides a lateral wall dew copper packaging structure, include: a plastic package body; the electronic assembly is plastically packaged in the plastic package body, one surface, close to the first surface of the plastic package body, of the electronic assembly is provided with at least one welding pad, the top surface and one side surface of the welding pad are exposed to the plastic package body, and the welding pad is used for being connected with an external component.

The utility model has the advantages that: by utilizing the half-cutting and full-cutting two-time cutting processes and anti-oxidation treatment such as tin melting, the top surface and one side surface of the welding pad in the formed side wall copper-exposed packaging structure are exposed to the plastic package body, the exposed area of the welding pad can be enlarged, the contact surface between the side wall copper-exposed packaging structure and an external component during fixed connection is increased, the weldability and the welding reliability are improved, the firmness of the fixed connection between the side wall copper-exposed packaging structure and the external component is improved, and the product reliability and yield are improved.

Drawings

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

Fig. 1 is a schematic view of a manufacturing process of a side-wall copper-exposed package structure according to the present invention;

fig. 2A to 2F are process flow diagrams of an embodiment of a manufacturing process of the side-wall copper-exposed package structure of the present invention;

fig. 3, the utility model discloses lateral wall dew copper packaging structure's cross-sectional view.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar components or components having the same or similar functions throughout. The utility model discloses directional phrase mentioned, for example: up, down, left, right, front, rear, inner, outer, lateral, etc., are simply directions with reference to the drawings. The embodiments described below by referring to the drawings and directional terms used are exemplary only for explaining the present invention, and are not to be construed as limiting the present invention. In addition, the present disclosure provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or use of other materials.

Please refer to fig. 1, which is a schematic step diagram of a manufacturing process of the side-wall copper-exposed package structure of the present invention. The manufacturing process comprises the following steps: s11: providing a plastic package body, wherein at least one electronic component is plastically packaged in the plastic package body, and one surface, close to the first surface of the plastic package body, of the electronic component is provided with at least one welding pad; s12: processing the first surface of the plastic package body, and exposing the top surface of the welding pad to the plastic package body; s13: performing half-cutting on the plastic package body along at least one side surface of the welding pad by adopting a first cutting knife so as to expose the corresponding side surface to the plastic package body; s14: and adopting a second cutting knife to completely cut the plastic package body to obtain at least one side wall copper exposure packaging structure. The above steps are described in detail below with reference to the accompanying drawings and embodiments.

Please refer to fig. 1 and fig. 2A to fig. 2F together, wherein fig. 2A to fig. 2F are process flow diagrams of an embodiment of a manufacturing process of the sidewall copper-exposed package structure of the present invention.

Regarding step S11: providing a plastic package body, wherein at least one electronic component is plastic-packaged in the plastic package body, and one surface of the electronic component, which is close to the first surface of the plastic package body, has at least one solder pad, please refer to fig. 1 and fig. 2A together, where fig. 2A is a cross-sectional view of the plastic package body provided in this embodiment. In this embodiment, two electronic components 22 are molded in the plastic package body 20, and two bonding pads 221 are disposed on a front surface (a surface close to the first surface of the plastic package body 20) of each of the electronic components 22. The electronic component 22 may be a chip or other device, such as an inductor, capacitor, resistor, etc. Preferably, the bonding pad 221 is an outer lead (out lead) of the electronic component 22, and the bonding pad 221 is made of a copper material. The molding compound 20 may be of a structure known in the art. In this embodiment, for clarity, the present invention provides two electronic components 22 in the plastic package body 20, in other embodiments, the electronic component plastic package body 20 may include one or more electronic components 22 in the plastic package body 20, each of the one or more electronic components 22 has one or more solder pads 221 on the electronic component 22, and the present invention does not limit the number of electronic components in the plastic package body 20 and the number and shape of solder pads on the electronic component. The pad 221 may be an outer lead (out lead) or a general lead (pin) of the electronic component 22.

In this embodiment, the plastic package body 20 is disposed with the electronic component 22 facing upward, and the subsequent cutting knife cuts from top to bottom. In other embodiments, the plastic package body 20 can also be disposed with the electronic component 22 facing downward, and the subsequent cutting knife cuts from bottom to top. The placing mode of the plastic package body 20 does not affect the technical scheme of the utility model. The utility model discloses do not prescribe a limit to the position of lateral wall copper-exposed packaging structure packaging method and welding pad on electronic component.

Regarding step S12: please refer to fig. 1 and fig. 2B together, in which fig. 2B is a cross-sectional view of the plastic package body exposed to the top surface of the bonding pad provided by this embodiment. The molding compound 20 is processed, so that the top surfaces 2211 of the pads 221 are exposed to the first surface of the molding compound 20, and are used as contact surfaces when the subsequently formed sidewall copper-exposed package structure is fixedly connected with an external component.

In a further embodiment, the first surface of the plastic package body 20 may be subjected to a surface mechanical polishing process to polish and thin the first surface of the plastic package body 20, so as to expose the top surfaces 2211 of the bonding pads 221 to the first surface of the plastic package body 20. The top surface of the copper welding pad is exposed on the first surface of the plastic package body to be used as a contact surface when the subsequently formed side wall copper-exposed packaging structure is fixedly connected with an external component.

Regarding step S13: fig. 1, fig. 2C, fig. 2D, and fig. 2E are also referred to, wherein fig. 2C is a cross-sectional view of the plastic package body half-cut according to the present embodiment, fig. 2D is a top view of the plastic package body half-cut according to the present embodiment, and fig. 2E is a cross-sectional view of the plastic package body after the half-cut according to the present embodiment. The first cutter 223 may be a thick cutter, the thickness of which is adapted to the distance between the adjacent pads 221 of the adjacent electronic components 22, and the height of the first cutter 223 is smaller than a preset height, so that the plastic package body 20 is subjected to thick-cutting half-cutting operation, and can be cut and formed at one time. The half-cut cutting depth is used to expose the respective side partially or completely to the plastic package body.

In a further embodiment, the plastic package body 20 may be half-cut along the side 2212 and/or the side 2214 of the pad 221 by using the first cutter 223 along the X direction in a top view, so as to partially or completely expose the side 2212 and/or the side 2214; the molding compound 20 may be half-cut along a side 2213 of the pad 221 by using a first cutter 223 along the Y direction in a top view, so as to partially or completely expose the side 2213; the plastic package body 20 can be half-cut along the side 2212 and/or the side 2214 of the bonding pad 221 and the side 2213 by using the first cutter 223 along the direction X, Y in the top view, so as to partially or fully expose the side 2212 and/or the side 2214 and partially or fully expose the side 2213. The plastic-sealed body 20 may be cut by using one first cutter 223, or the plastic-sealed body 20 may be cut by using a plurality of first cutters 223 at the same time.

After the half-cut operation, the pad 221 may include one, two, or three sides exposed to the molding compound 20, that is, at this time, the top surface 2211 and at least one side (2212/2213/2214) of the pad 221 are exposed to the molding compound 20, so that when the subsequently formed sidewall copper-exposed package structure is fixedly connected to an external member, a contact area of the connection is increased.

Preferably, the manufacturing process further comprises: and performing surface oxidation prevention treatment on the half-cut bonding pad, so as to prevent the part of the bonding pad 221 exposed to the plastic package body 20 after half-cutting from being oxidized. In this embodiment, the surface oxidation preventing treatment further includes: carrying out tin melting treatment on the part of the welding pad 221 exposed to the plastic package body 20; that is, a layer of tin is deposited on the position of the bonding pad 221 by a chemical method, and the thickness is very thin, generally 10 to 30 micrometers, so as to mainly prevent the oxidation of the portion (the top surface 2211 and at least one side surface (2212/2213/2214)) of the bonding pad 221 exposed to the molding compound 20, and to better connect the formed sidewall copper-exposed package structure with an external component by SMT tin fusion. SMT (Surface Mount Technology), is a Technology and process currently prevalent in the electronic assembly industry. The surface mount device (SMC/SMD, also called chip component) with no pins or short leads is mounted on the surface of PCB or other substrate, and is soldered and assembled by reflow soldering or dip soldering. In other embodiments, the surface oxidation prevention operation may be performed on the solder pad by using a nickel alloy, a tin spray, or an organic layer spray.

Regarding step S14: a second cutting knife is used to cut the plastic package body completely along a direction perpendicular to the first surface to obtain at least one side wall copper-exposed package structure, please refer to fig. 1 and fig. 2F together, where fig. 2F is a cross-sectional view of the plastic package body completely cut according to the present embodiment.

The top surface 2211 and at least one side surface (2212/2213/2214) of the pad 221 are exposed to the molding compound 20, and are used as contact surfaces for connection when the subsequent side-wall copper-exposed package structure is fixedly connected to an external component. Preferably, the pad 221 is connected to an external member as an outer lead of the sidewall copper-exposed package structure.

A second cutting knife 224 may be used to cut the plastic package body 20 longitudinally/transversely, respectively, so as to form an independent sidewall copper-exposed package structure. A plurality of second cutting knives 224 may also be used to simultaneously cut the plastic package body 20 in the longitudinal/transverse direction.

In an embodiment, the thickness of the second cutter 224 is smaller than the thickness of the first cutter 223, and the height of the second cutter 224 is larger than the height of the first cutter 223. The thickness of the second cutting blade 224 is smaller than the distance between the adjacent bonding pads 221 of the adjacent electronic components 22, and the height thereof is larger than a preset height, so that the second cutting blade can cut through the adjacent electronic components 22 to complete the full-cutting operation. After the full cut operation, a separate sidewall copper-exposed package structure 30 is formed, as shown in fig. 3.

In another embodiment, the second cutter 224 may employ the same cutter as the first cutter 223. The thickness of the second cutter 224 is equal to the distance between the adjacent bonding pads 221 of the adjacent electronic components 22, and the height thereof is greater than a preset height, so that the second cutter can cut through the adjacent electronic components 22 to complete the full cutting operation; and the side surface of the exposed part of the bonding pad 221 is flush with the corresponding side surface of the plastic package body 20 after the full cutting operation. After the full cut operation, a separate sidewall copper-exposed package structure 40 is formed, as shown in fig. 4.

The utility model discloses lateral wall dew copper packaging structure preparation technology utilizes half to cut, cut twice cutting process entirely to and through anti-oxidation treatment such as tin, the top surface and the at least one side of weld pad all expose in the plastic-sealed body among the lateral wall dew copper packaging structure who forms, it can enlarge the exposed area of weld pad, contact surface when increasing lateral wall dew copper packaging structure and external component and carrying out fixed connection improves weldability and welded reliability, thereby improve the fastness of the two fixed connection, improve product yield and reliability.

Referring to fig. 3, a cross-sectional view of the sidewall copper-exposed package structure of the present invention is shown. The sidewall copper-exposed package structure 30 includes: the electronic device comprises a plastic package body 20 and at least one electronic component 22 which is plastic-packaged in the plastic package body 20. The side of the electronic component 22 close to the first surface of the plastic package body 20 has at least one pad 221, the top 2211, the side 2212 and the side 2213 of the pad 221 are exposed to the plastic package body 20, and the pad 221 is used for connecting with an external member (not shown in the figure).

The molding compound 20 may be of a structure known in the art. In this embodiment, for clarity, the front surface (the surface close to the first surface of the plastic package body 20) of the electronic component 22 has two pads 221, the pads 221 are made of copper material, and the pads 221 are outer pins (outer) of the electronic component 22. In other embodiments, the front surface of the electronic component 22 may have one or more pads 221, the present invention is not limited to the number of the electronic components 22 in the plastic package body 20, and the number and shape of the pads on the electronic component 22, and the pads 221 may be outer pins (out leads) or general pins (pins) of the electronic component 22.

In a further embodiment, the bonding pad 221 is prepared by performing half-cutting on the plastic package body 20 along the side 2212 and the side 2213 of the bonding pad, and performing full-cutting twice-cutting process on the plastic package body 20.

Preferably, the portion of the bonding pad 221 exposed to the plastic package body 20 (the top surface 2211 and at least one side surface (2212/2213/2214)) is subjected to tin melting treatment. The tin treatment is mainly aimed at preventing oxidation, and at the same time, better performing SMT tin fusion when the subsequent side wall copper-exposed packaging structure 30 is connected with an external member. In other embodiments, the surface oxidation prevention operation may be performed on the solder pad by using a nickel alloy, a tin spray, or an organic layer spray.

Referring to fig. 4, a cross-sectional view of a side-wall copper-exposed package structure according to a second embodiment of the present invention is shown. The difference from the embodiment shown in fig. 3 is that, in the present embodiment, in the sidewall copper-exposed package structure 40, the side where the bonding pad 221 is exposed is flush with the corresponding side of the plastic package body 20.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The utility model provides a lateral wall dew copper packaging structure which characterized in that includes:

a plastic package body;

the electronic assembly is plastically packaged in the plastic package body, one surface, close to the first surface of the plastic package body, of the electronic assembly is provided with at least one welding pad, the top surface and at least one side surface of the welding pad are exposed to the plastic package body, and the welding pad is used for being connected with an external component.

2. The package structure of claim 1, wherein at least one side of the pad is partially or completely exposed to the molding compound.

3. The package structure of claim 1, wherein the bonding pad is made of copper material.

4. The packaging structure with exposed copper on the side wall according to claim 1, wherein the solder pad is prepared by performing half-cutting on the plastic package body along at least one side of the solder pad and performing full-cutting twice-cutting process on the plastic package body.

5. The package structure with exposed copper on the side wall according to claim 1, wherein a portion of the bonding pad exposed to the molding compound is subjected to a tin-melting treatment.

6. The package structure of claim 1, wherein the pad is used as an outer lead of the package structure to connect with an external component.