阅读说明：本技术 一种封装结构及其制造方法 (Packaging structure and manufacturing method thereof ) 是由 曹周 于 2020-05-18 设计创作，主要内容包括：本发明公开了一种封装结构及其制造方法,属于电子元器件封装技术领域。封装结构包括：沿第一方向相对设置的第一芯片和第二芯片；第一引线框架和第二引线框架,其中,所述第一芯片连接于所述第一引线框架上；所述第二引线框架包括支撑部和设于所述支撑部沿第二方向两侧的两个连接部,所述第二芯片连接于所述第二引线框架的所述支撑部上,所述第二引线框架的所述连接部与所述第一引线框架连接；所述第一方向与所述第二方向相互垂直。本发明的封装结构保证封装质量的同时,还避免了采用传统堆叠方式时所产生的芯片热量聚集现象,有利于芯片的快速散热。(The invention discloses a packaging structure and a manufacturing method thereof, and belongs to the technical field of electronic component packaging. The package structure includes: the chip comprises a first chip and a second chip which are oppositely arranged along a first direction; the chip package comprises a first lead frame and a second lead frame, wherein the first chip is connected to the first lead frame; the second lead frame comprises a supporting part and two connecting parts arranged on two sides of the supporting part along a second direction, the second chip is connected to the supporting part of the second lead frame, and the connecting parts of the second lead frame are connected with the first lead frame; the first direction and the second direction are perpendicular to each other. The packaging structure of the invention ensures the packaging quality, avoids the phenomenon of chip heat accumulation generated by adopting the traditional stacking mode, and is beneficial to the quick heat dissipation of the chip.)

1. A package structure, comprising:

a first chip (21) and a second chip (22) which are arranged oppositely along a first direction;

a first lead frame (11) and a second lead frame (12), wherein the first chip (21) is connected to the first lead frame (11);

the second lead frame (12) comprises a supporting part (121) and two connecting parts (122) arranged on two sides of the supporting part (121) along a second direction, the second chip (22) is connected to the supporting part (121) of the second lead frame (12), and the connecting parts (122) of the second lead frame (12) are connected with the first lead frame (11);

the first direction and the second direction are perpendicular to each other.

2. The package structure according to claim 1, further comprising a first wire (31) and a second wire (32), the first wire (31) electrically connecting the first chip (21) and the first lead frame (11), the second wire (32) electrically connecting the second chip (22) and the second lead frame (12).

3. The package structure according to claim 1, wherein the second leadframe (12) is a unitary structure.

4. The package structure according to claim 1, wherein the angle between the support portion (121) and the connecting portion (122) is a right angle or an obtuse angle.

5. The package structure according to claim 1, wherein the connection portion (122) of the second lead frame (12) is connected to the first lead frame (11) by a non-conductive material.

6. The package structure according to claim 1, wherein the connection portion (122) of the second lead frame (12) is connected to the first lead frame (11) by a conductive material.

7. The package structure according to claim 1, further comprising a molding compound (41), wherein the molding compound (41) is used for encapsulating the first lead frame (11), the second lead frame (12), the first chip (21) and the second chip (22).

8. The package structure according to claim 7, wherein the first lead frame (11) is provided with a first heat dissipation surface (111) at a side away from the first chip (21), the support portion (121) of the second lead frame (12) is provided with a second heat dissipation surface (123) at a side away from the second chip (22), and the first heat dissipation surface (111) and the second heat dissipation surface (123) are exposed outside the plastic package body (41).

9. A method for manufacturing a package structure according to any one of claims 1 to 8, comprising the steps of:

s1: preparing a first lead frame (11) and a second lead frame (12);

s2: -assembling a first chip (21) with the first lead frame (11); -assembling a second chip (22) with the second lead frame (12);

s3: assembling the first lead frame (11) and the second lead frame (12) to finally dispose the first chip (21) and the second chip (22) opposite to each other in a first direction;

s4: and (7) injection molding and packaging.

10. The manufacturing method according to claim 9, wherein step S2 specifically includes the steps of:

s21: -connecting the first chip (21) to the first lead frame (11), the second chip (22) to the support (121) of the second lead frame (12);

s22: a first wire (31) connects the first chip (21) and the first lead frame (11), and a second wire (32) connects the second chip (22) and the second lead frame (12).

Technical Field

The invention relates to the technical field of electronic component packaging, in particular to a packaging structure and a manufacturing method thereof.

Background

With the smaller volume of electronic component products, the packaging technology is also rapidly developed. QFN (quad flat Non-lead) package technology does not have gull-wing leads like the conventional package, and has short conductive paths between inner leads and pads, low self-inductance and wiring resistance in the package, so that QFN packages can provide excellent electrical performance.

As the package tends to develop toward multiple chips, QFN packages often use stacked packages to package multiple chips. Referring to fig. 1, because the package thickness of the QFN package is small, when a multi-chip package is performed by stacking, the metal wires 200 'between different chips 100' and a lead frame 300 'are likely to interfere with each other, which affects the performance of the packaged product, and the heat of the chip 100' is also collected in the stacking area and cannot be effectively dissipated, so that the heat dissipation performance of the whole product is poor, and an additional heat sink is often required to assist heat dissipation, which is particularly not suitable for the package of a power device chip, thereby increasing the manufacturing process and the cost.

Therefore, it is desirable to provide a package structure and a method for manufacturing the same to solve the above problems.

Disclosure of Invention

The invention aims to provide a packaging structure, which ensures the packaging quality, avoids the phenomenon of chip heat accumulation generated by adopting a traditional stacking mode and is beneficial to the quick heat dissipation of chips.

The invention also aims to provide a manufacturing method of the packaging structure, which can conveniently and quickly realize the manufacturing of the packaging structure.

In order to realize the purpose, the following technical scheme is provided:

a package structure, comprising:

the chip comprises a first chip and a second chip which are oppositely arranged along a first direction;

the chip package comprises a first lead frame and a second lead frame, wherein the first chip is connected to the first lead frame;

the second lead frame comprises a supporting part and two connecting parts arranged on two sides of the supporting part along a second direction, the second chip is connected to the supporting part of the second lead frame, and the connecting parts of the second lead frame are connected with the first lead frame;

the first direction and the second direction are perpendicular to each other.

As a preferable scheme of the above package structure, the package structure further includes a first wire and a second wire, the first wire is electrically connected to the first chip and the first lead frame, and the second wire is electrically connected to the second chip and the second lead frame.

As a preferable scheme of the above package structure, the second lead frame is an integrated structure.

As a preferable scheme of the above packaging structure, an included angle between the support portion and the connection portion is a right angle or an obtuse angle.

In a preferred embodiment of the package structure, the connection portion of the second lead frame is connected to the first lead frame through a non-conductive material.

As a preferable mode of the above package structure, the connection portion of the second lead frame is connected to the first lead frame through a conductive material.

As a preferable scheme of the above package structure, the package structure further includes a plastic package body, and the plastic package body is used for wrapping the first lead frame, the second lead frame, the first chip, and the second chip.

As a preferable scheme of the above package structure, the first lead frame is provided with a first heat dissipation surface on a side away from the first chip, the supporting portion of the second lead frame is provided with a second heat dissipation surface on a side away from the second chip, and the first heat dissipation surface and the second heat dissipation surface are exposed outside the plastic package body.

A method for manufacturing a package structure according to any of the above, comprising the steps of:

s1: preparing a first lead frame and a second lead frame;

s2: assembling a first chip with the first lead frame; assembling a second chip with the second lead frame;

s3: assembling the first lead frame and the second lead frame, and finally enabling the first chip and the second chip to be oppositely arranged in a first direction;

s4: and (7) injection molding and packaging.

As a preferable embodiment of the above manufacturing method, step S2 specifically includes the steps of:

s21: connecting the first chip to the first lead frame, and connecting the second chip to the supporting portion of the second lead frame;

s22: a first wire connects the first chip and the first lead frame, and a second wire connects the second chip and the second lead frame.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, the second chip is arranged by arranging the second lead frame, and the second chip is stably supported by the connection of the second lead frame and the first lead frame, so that the first chip and the second chip are oppositely arranged in the vertical direction, a safe insulation distance is reserved between the two chips, and the two chips are not interfered with each other with a lead between the corresponding lead frames, thereby ensuring the packaging quality and not influencing the product performance of the packaging piece; secondly, the first chip and the second chip are arranged oppositely, the phenomenon of chip heat accumulation caused by stacking is avoided, each chip can radiate heat through the lead frame directly connected with the chip, the radiating speed of the packaging piece is improved, the packaging piece does not need to use a radiating element, the manufacturing process is simplified, and the cost is reduced.

Drawings

FIG. 1 is a diagram of a package structure in the prior art;

FIG. 2 is a diagram illustrating a package structure according to an embodiment of the present invention;

fig. 3 is a flowchart illustrating a method for manufacturing a package structure according to an embodiment of the invention.

Reference numerals:

100' -chip; 200' -a metal wire; 300' -a lead frame;

11-a first lead frame; 12-a second lead frame; 21-a first chip; 22-a second chip; 31 — a first wire; 32-a second conductive line; 41-plastic package body;

111-a first heat dissipating surface; 121-a support; 122-a connecting portion; 123-second heat dissipation surface.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that are conventionally placed when the products of the present invention are used, and are used only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements to be referred to must have specific orientations, be constructed in specific orientations, and operate, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed" and "connected" are to be interpreted broadly, e.g., as being either fixedly connected, detachably connected, or integrally connected; either mechanically or electrically. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

As shown in fig. 2, the present embodiment provides a package structure, which specifically includes:

a first chip 21 and a second chip 22 disposed opposite to each other in a first direction;

a first lead frame 11 and a second lead frame 12, wherein the first chip 21 is connected to the first lead frame 11; the second lead frame 12 includes a support portion 121 and two connection portions 122 disposed on both sides of the support portion 121 in the second direction, the second chip 22 is connected to the support portion 121 of the second lead frame 12, and the connection portions 122 of the second lead frame 12 are connected to the first lead frame 11; the first direction and the second direction are perpendicular to each other.

Further, in order to electrically connect the chip and the lead frame, the package structure further includes a first wire 31 and a second wire 32, wherein the first wire 31 is used to electrically connect the first chip 21 and the first lead frame 11, and the second wire 32 is used to electrically connect the second chip 22 and the second lead frame 12. Further, the first and second conductive lines 31 and 32 are each made of a metal or an alloy having excellent conductivity.

In this embodiment, the first direction is a vertical direction, and the second direction is a horizontal direction, which may be understood as a Z direction and an X direction of a rectangular coordinate system. The second chip 22 is arranged by arranging the second lead frame 12, and the second chip 22 is stably supported by the connection of the second lead frame 12 and the first lead frame 11, so that the first chip 21 and the second chip 22 are arranged oppositely in the vertical direction, a safe insulation distance is reserved between the two chips, and the two chips are not interfered with each other with a lead wire between the corresponding lead frames, thereby ensuring the packaging quality and not influencing the product performance of the packaging part; secondly, the first chip 21 and the second chip 22 are arranged oppositely, so that the phenomenon of chip heat accumulation caused by stacking is avoided, each chip can dissipate heat through the lead frame directly connected with the chip, the heat dissipation speed of the packaging part is improved, the packaging part does not need to use a heat dissipation element, the manufacturing process is simplified, and the cost is reduced.

Further, the second lead frame 12 is of an integral structure, i.e., the supporting portion 121 and the connecting portion 122 of the second lead frame 12 are integrally molded. Alternatively, the second lead frame 12 is generally a plate material, and thus the second lead frame 12 is formed by bending. Preferably, the supporting portion 121 is disposed opposite to the first lead frame 11, the connecting portion 122 is bent by 90 degrees relative to the supporting portion 121 in a direction approaching to the first lead frame 11, that is, the connecting portion 122 extends in the first direction and is connected to the first lead frame 11, and the second lead frame 12 has a U-shaped cross section. Further preferably, in some other embodiments, in consideration that the height dimension of the package should be compressed as much as possible, the bending angle of the connecting portion 122 relative to the supporting portion 121 may also be made smaller than 90 degrees, that is, the included angle therebetween is an obtuse angle, in which case the connecting portion 122 is disposed at an included angle with the first direction, and the cross section of the second lead frame 12 is a trapezoidal structure. In practice, the specific bending angle of the connecting portion 122 should ensure a certain safety distance between the second chip 22 connected to the supporting portion 121 and the first chip 21, so as to ensure the insulation therebetween, and the electrical signals of the chips can only be transmitted through the second wires 32 and the second lead frame 12.

For different product requirements, the second chip 22 can be divided into two cases, that is, the second chip needs to be electrically connected and the second chip does not need to be electrically connected, so that the second chip 22 and the first lead frame 11 need to be electrically connected at times and need not to be electrically connected at times. Therefore, the connection between the second lead frame 12 and the first lead frame 11 has two cases, one is an insulation connection and one is an electrical connection. Therefore, the connection portion 122 of the second lead frame 12 and the first lead frame 11 are connected by using a conductive material or a non-conductive material. Specifically, the non-conductive material can be epoxy resin and the like; the conductive material can be silver paste. Further, the first chip 21 and the first lead frame 11, and the second chip 22 and the support portion 121 of the second lead frame 12 are connected by solder bonding.

The package structure further includes a plastic package body 41 for encapsulating the first lead frame 11, the second lead frame 12, the first chip 21 and the second chip 22, thereby forming a package. Optionally, the plastic package body 41 is made of an epoxy plastic package material, so that the chip and the external environment can be effectively isolated, and the chip is prevented from being affected by external moisture, solvent, impact and the like.

In order to better realize the heat dissipation of the chip, optionally, the first lead frame 11 is provided with a first heat dissipation surface 111 at a side far away from the first chip 21, the supporting portion 121 of the second lead frame 12 is provided with a second heat dissipation surface 123 at a side far away from the second chip 22, and both the first heat dissipation surface 111 and the second heat dissipation surface 123 are exposed outside the plastic package body 41, that is, the heat dissipation surfaces are not covered during the plastic package, but are exposed in the external environment, so that the heat generated by the corresponding chips can be dissipated to the outside through the heat dissipation surfaces, thereby realizing the rapid heat dissipation and further improving the heat dissipation performance of the whole package structure.

It should be noted that the schematic diagrams provided in the present embodiment are all schematic cross-sectional diagrams of the package structure at a certain cross-section, and therefore, the first chip 21 refers to a type of chip on the first lead frame 11, and the number thereof is limited to one; similarly, the second chip 22 refers to a type of chip on the second lead frame 12, and the number of chips is not limited to one.

Referring to fig. 3, the present embodiment further provides a manufacturing method for manufacturing the package structure, which specifically includes the following steps:

s1: preparing a first lead frame 11 and a second lead frame 12;

s2: assembling the first chip 21 and the first lead frame 11; assembling the second chip 22 with the second lead frame 12;

s3: assembling the first lead frame 11 and the second lead frame 12, and finally arranging the first chip 21 and the second chip 22 opposite to each other in the first direction;

s4: and (7) injection molding and packaging.

For the integrated second lead frame 12, the step S1 specifically includes the steps of:

s11: bending the second lead frame 12 to form a support portion 121 and two connection portions 122; the support portion 121 is used to connect the second chip 22, and the connection portion 122 is used to connect with the first lead frame 11.

Further, step S2 specifically includes the steps of:

s21: the first chip 21 is connected to the first lead frame 11, and the second chip 22 is connected to the support portion 121 of the second lead frame 12;

s22: the first wire 31 connects the first chip 21 and the first lead frame 11, and the second wire 32 connects the second chip 22 and the second lead frame 12.

It is noted that, in steps S1 and S2, the preparation and assembly of the first lead frame 11 and the first chip 21, the preparation and assembly of the second lead frame 12 and the second chip 22 may be performed simultaneously, thereby improving the manufacturing efficiency of the package structure.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.