Packaging frame and packaging structure

Abstract

The utility model belongs to the technical field of chip packaging, and discloses a packaging frame and a packaging structure. The packaging frame comprises a frame base body, a base island, a supporting frame and pins, a base island fixing area and an etching area are arranged on the frame base body, the etching area is located on the outer side of the base island fixing area, the base island is arranged on the base island fixing area, and the water-drop-shaped pins are arranged in the etching area and connected with the supporting frame through connecting ribs. The size and the area of a single pin are effectively reduced, and consumables in electroplating and welding processes are reduced; under the condition that the number of the pins is not changed, a larger distance can be formed between the pins, and the possibility of invisible short circuit caused by connection formed between the pins due to excessive soldering tin or overflowing from a bonding pad in the welding process of the circuit board is effectively reduced. And the outlines of the pins are linear, so that the flowing of a plastic package material is facilitated in the packaging process, and the insufficient filling of a product caused by packaging material overflow and insufficient fluidity of the plastic package material is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of chip packaging, in particular to a packaging frame and a packaging structure. Background Art

[0002] An integrated circuit is a microstructure that connects the transistors, resistors, capacitors and other components required in a circuit and is manufactured on one or several small pieces of semiconductor lenses or dielectric substrates, and then packaged in a tube shell to become a miniature structure with circuit functions.

[0003] In the prior art, packaging structures include Quad Flat No-lead Package (QFN) and Dual Flat No-lead Package (DFN). These packaging structures adopt ultra-thin and small appearance size and semi-encapsulated structure. The pins are rectangular and the corners are arc-shaped. The pin area is large, which may cause the pins and the frame back film to be only partially bonded and unstable, resulting in overflow after plastic sealing; the consumables are too large during electroplating and circuit board welding; the pin size is large and the spacing between the pins is small, which may easily cause contact and short circuit during soldering.

[0004] That is, the pins of the existing packaging structure are rectangular with arc-shaped corners, large area and small spacing, which is prone to overflow after plastic packaging, short circuit and excessive consumables during electroplating and welding. Utility Model Content

[0005] The utility model aims to provide a packaging frame and a packaging structure to solve the problems that the existing pins are rectangular with arc-shaped corners, have a large area and a small spacing, are prone to overflow and short circuit after plastic sealing, and increase the risk of moisture and delamination.

[0006] To achieve this purpose, the utility model adopts the following technical solutions:

[0007] The utility model provides a packaging frame, which comprises:

[0008] A frame substrate, wherein a base island fixing area and an etching area are provided on the frame substrate, and the etching area is located at the periphery of the base island fixing area;

[0009] A supporting frame, arranged between the etching area and the base island;

[0010] A base island is arranged on the base island fixing area, the base island is used to fix the chip, and the base island is connected to the frame substrate through the supporting frame;

[0011] A pin is arranged in the etching area, the pin is in a water drop shape, and the pin is connected to the supporting frame through a connecting rib.

[0012] As an optional technical solution for a packaging frame, the pin has a maximum width and a minimum width along the extension direction, and the maximum width is 6 to 8 times the minimum width.

[0013] As an optional technical solution for a packaging frame, the pin has a large end and a small end, the large end is located between the base island and the small end, and the small end is connected to the connecting rib.

[0014] As an optional technical solution for a packaging frame, a plurality of pins are provided, and the plurality of pins are divided into two groups or four groups, and each two groups are respectively provided on opposite sides of the packaging frame and are axially symmetrically arranged along the transverse center line or the longitudinal center line of the packaging frame.

[0015] As an optional technical solution for a packaging frame, the packaging frame is made of metal or alloy material.

[0016] As an optional technical solution for a packaging frame, the packaging frame is square or rectangular.

[0017] As an optional technical solution for a packaging frame, a lock hole is provided on the packaging frame.

[0018] The utility model provides a packaging structure, which comprises a chip, a plastic packaging material and a packaging frame, wherein the chip is arranged on the surface of the base island, the chip is connected to the pin through a welding wire, and the etching area, the base island fixing area and the welding wire are all plastic-sealed in the plastic packaging material.

[0019] As an optional technical solution for a packaging structure, a half-etched edge area is provided at the edge of each pin, a half-etched groove is provided at the edge area, and the edge area and the groove are filled with the molding compound.

[0020] As an optional technical solution for a packaging structure, the support frame and the groove are both in the shape of a Chinese umbilical cord.

[0021] Beneficial effects:

[0022] The utility model provides a packaging frame, which includes a frame substrate, a base island, a support frame and pins. The frame substrate is provided with a base island fixing area and an etching area, the etching area is located outside the base island fixing area, the base island is arranged on the base island fixing area, the support frame is arranged between the etching area and the base island, the base island is connected to the frame substrate through the support frame, and by arranging a water drop-shaped pin in the etching area and the pin is connected to the support frame through a connecting rib, the size and area of ​​a single pin are effectively reduced, and consumables are reduced during electroplating and welding; without changing the number of pins, the pins can have a larger spacing, effectively reducing the possibility of excessive solder or overflow from the pad during the circuit board welding process to form a connection between the pins to cause an invisible short circuit. The pin contour is linear, which is more conducive to the flow of plastic encapsulation material during the encapsulation process, thereby avoiding encapsulation overflow and insufficient product filling caused by insufficient fluidity of the plastic encapsulation material.

[0023] The utility model provides a packaging structure, which includes a chip, a plastic packaging material and a packaging frame, wherein the chip is arranged on the surface of a base island, the chip is connected to a pin through a welding wire, and an etching area, a base island fixing area and a welding wire are all plastic-sealed in the plastic packaging material. By arranging a packaging frame with a water drop-shaped pin, since the water drop-shaped pin structure has a smaller area, it can ensure that the pin and the back film of the packaging frame can be completely bonded, and it is avoided that only part of the pin is bonded to the back film of the packaging frame due to an excessively large area, thereby improving the stability of the packaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the front structure of a packaging frame in the prior art;

[0025] Figure 2 It is a front structural schematic diagram of a packaging frame provided by an embodiment of the utility model;

[0026] Figure 3 It is a schematic diagram of the back structure of the packaging frame provided by an embodiment of the utility model.

[0027] In the figure:

[0028] 1. Pins; 2. Base island; 3. Connecting ribs; 4. Frame base; 5. Support frame; 6. Keyhole. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0030] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0032] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0033] Figure 1 Schematic diagram of the structure of the packaging frame in the prior art, wherein the pin 1 is rectangular and the corners of the rectangle are arc-shaped. Figure 2 and Figure 3 As shown, this embodiment provides a packaging frame and a packaging structure, the packaging frame includes a pin 1, a base island 2, a connecting rib 3, a frame base 4 and a supporting frame 5, the frame base 4 is provided with a base island fixing area and an etching area, the etching area is located at the periphery of the base island fixing area; the base island 2 is arranged on the base island fixing area, and the base island 2 is used to fix the chip; the supporting frame 5 is arranged between the etching area and the base island 2, and the base island 2 is connected to the frame base 4 through the supporting frame 5; the pin 1 is arranged in the etching area, the pin 1 is in a water drop shape, and the pin 1 is connected to the supporting frame 5 through the connecting rib 3.

[0034] Specifically, the pin 1 is directly connected to the connecting rib 3, and the four corners of the base island 2 are connected to the frame base 4 through the supporting frame 5; the pin 1 is connected to the end edge of the supporting frame 5 through the connecting rib 3. Preferably, the package frame is made of metal or alloy material; the pin 1 and the base island 2 are made of copper material and the surface is silver-plated.

[0035] The leadless quad flat package and the dual-plane leadless package are two types of package structures. The steps of chip packaging include thinning, dicing, mounting, bonding, plastic sealing, deburring, electroplating, printing, and rib cutting. The specific structure, steps and principles can be understood by referring to the existing technology, and will not be repeated here. In the QFN package, the package frame is square, the overall appearance of the package structure is square, the water drop-shaped pins 1 are divided into four groups, and the four groups of pins 1 are distributed at the four edges of the package structure; in the DFN package, the package frame is rectangular, the overall appearance of the package structure is rectangular, the water drop-shaped pins 1 are divided into two groups, and the two groups of pins 1 are distributed at the opposite sides of the package structure; the pins 1 are arranged symmetrically along the horizontal center line or the vertical center line of the package frame.

[0036] This embodiment adopts QFN packaging; the base island fixing area is square and the etching area is U-shaped; each frame substrate 4 includes at least one base island 2 and four teardrop-shaped pins 1; the pin 1 has a maximum width and a minimum width along the extension direction, and the maximum width is 6 to 8 times the minimum width; the pin 1 has a large end and a small end, the large end is located between the base island 2 and the small end, and the small end is connected to the connecting rib 3.

[0037] Furthermore, the packaging frame is provided with locking holes 6. In this embodiment, the locking holes 6 are arranged at the four corners of the packaging frame. The provision of the locking holes 6 is conducive to improving the reliability of packaging.

[0038] By setting pin 1 to be in a teardrop shape, compared with the existing rectangular pin 1 with rounded corners, setting pin 1 to be in a teardrop shape effectively reduces the size and area of ​​a single pin 1. Without changing the number of pins 1, the pins 1 can have a larger spacing, effectively avoiding the problem of excessive solder or overflow from the pad during the circuit board welding process, thereby forming a connection between pins 1 and causing an invisible short circuit.

[0039] Die bonding, also known as wafer bonding, is the process of tightly combining the chip and the carrier through materials and technology, and is the core link in the semiconductor packaging process. The die bonding process is completed by a die bonding machine. The chip and die bonding glue are prepared, and the chip and the packaging frame are firmly fixed together through heating and pressure, which has a direct impact on the performance, stability and life of semiconductor products. Set pin 1 to a water drop shape. During the die bonding and bonding wire bonding stages, due to the obvious water drop shape characteristics, it is easier to find the reference point of the packaging frame, which is easy to identify and has high recognition accuracy.

[0040] In the product encapsulation stage, due to the smaller structural area of the water-drop-shaped lead 1, it can ensure that the lead 1 and the back film of the encapsulation frame can be completely adhered, avoiding the situation that only part of the lead 1 is adhered to the back film of the encapsulation frame due to too large an area. Moreover, the lead 1 with a linear water-drop shape is more conducive to the flow molding of the encapsulation material during the encapsulation process, thus avoiding problems such as encapsulation overflow and insufficient product filling caused by insufficient fluidity of the encapsulation material.

[0041] This embodiment also provides an encapsulation structure, which includes a chip, an encapsulation material, and an encapsulation frame. The chip is disposed on the surface of the base island 2, and the chip is connected to the lead 1 through bonding wires. The etching area, the base island fixing area, and the bonding wires are all encapsulated in the encapsulation material. By providing an encapsulation frame with water-drop-shaped leads 1, due to the smaller structural area of the water-drop-shaped leads 1, it can ensure that the leads 1 and the back film of the encapsulation frame can be completely adhered, avoiding the situation that only part of the leads 1 is adhered to the back film of the encapsulation frame due to too large an area, and improving the stability of the encapsulation.

[0042] In the prior art, the lead 1 is located at the bottom of the encapsulation body, resulting in the need for the bonding part between the lead 1 and the encapsulation body to bear severe external pressure. In this embodiment, leads 1 are respectively disposed at the four edges of the encapsulation frame, and four water-drop-shaped leads 1 are spaced apart at each edge. The leads 1 are embedded and encapsulated in the encapsulation body, and all the leads 1 are annularly disposed around the base island 2, that is, the leads 1 and the encapsulation body form an annular embedded structure. By forming the annular embedded structure, it is beneficial to improve the bonding force between the leads 1 and the encapsulation body, improve the delamination resistance of the leads 1, and ensure the reliability of the encapsulation.

[0043] The encapsulation material encapsulates the etching area, the base island 2, the chip, and the bonding wires, etc. in the encapsulation material by means of encapsulation and curing. The encapsulation material is in the shape of a cuboid, usually formed into small cylinders, and becomes a liquid to coat the chip and the encapsulation frame during encapsulation, and finally cures and forms; it is堆砌 by powder granular materials of the encapsulation material. The encapsulation material uses epoxy resin.

[0044] Specifically, the etching area includes multiple leads 1, and a semi-etched edge area is provided at the edge of each lead 1. A semi-etched groove is provided in the edge area, and the edge area and the groove are filled with the encapsulation material. By providing the semi-etched groove and the edge area to form a stepped shape, it can increase the adhesion area and adhesion strength between the encapsulation material and the leads 1. Improve the reliability of the encapsulation and the stability of the chip. In the QFN encapsulation, the shapes of the support frame 5 and the groove are both in a zigzag shape.

[0045] Since the small end of the pin 1 is connected to the connecting rib 3, the size and area of ​​the pin 1 are reduced, thereby reducing the width of the connecting rib 3. Within the unit size, the number of effective input / output units (Input / Output, I / O) is increased, which can provide more design space for the structural layout of more pins 1; the width of the connecting rib 3 is reduced, so that the structure of the package pin 1 can effectively reduce the metal burr problem during the special plastic package cutting process, and optimize and improve the effect of the plastic package cutting process.

[0046] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A packaging frame, characterized in that: Comprising: A frame substrate (4), on which a base island fixing area and an etching area are provided, and the etching area is located on the outer periphery of the base island fixing area; A support border (5), arranged between the etching area and the base island (2); A base island (2), arranged on the base island fixing area, and the base island (2) is used for fixing a chip, and the base island (2) is connected to the frame substrate (4) through the support border (5); Leads (1), arranged in the etching area, the leads (1) are in a water droplet shape, and the leads (1) are connected to the support border (5) through connecting ribs (3); the leads (1) have a maximum width and a minimum width along the extending direction, and the maximum width is 6-8 times the minimum width; the leads (1) have a large end and a small end, the large end is located between the base island (2) and the small end, and the small end is connected to the connecting rib (3).

2. The packaging frame according to claim 1, characterized in that: A plurality of the leads (1) are provided, and the plurality of leads (1) are divided into two groups or four groups, and every two groups are respectively arranged on opposite sides of the package frame and are axially symmetrically arranged along the horizontal center line or the vertical center line of the package frame.

3. The packaging frame according to claim 1, characterized in that: The package frame is made of a metal or alloy material.

4. The packaging frame according to claim 1, characterized in that: The package frame is square or rectangular.

5. The packaging frame according to claim 1, characterized in that: A lock hole (6) is formed in the package frame.

6. A packaging structure, characterized in that: Comprising a chip, a molding compound and the package frame according to any one of claims 1-5, the chip is arranged on the surface of the base island (2), the chip is connected to the leads (1) through bonding wires, and the etching area, the base island fixing area and the bonding wires are all encapsulated in the molding compound.

7. The packaging structure according to claim 6, characterized in that: A semi-etched edge area is provided at the edge of each of the leads (1), and a semi-etched groove is provided in the edge area, and the molding compound is filled in the edge area and the groove.

8. The packaging structure according to claim 7, characterized in that: The shapes of the support border (5) and the groove are both in a shape of a Chinese character 'hui'.

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