CN212209466U

CN212209466U - High-density QFN (quad Flat No lead) packaging structure

Info

Publication number: CN212209466U
Application number: CN202021203792.XU
Authority: CN
Inventors: 骆宗友
Original assignee: Dongguan Jiajun Science & Technology Co ltd
Current assignee: Dongguan Jiajun Science & Technology Co ltd
Priority date: 2020-06-24
Filing date: 2020-06-24
Publication date: 2020-12-22
Anticipated expiration: 2030-06-24

Abstract

The utility model provides a high-density QFN packaging structure, which comprises a packaging body, wherein a central bonding pad is arranged at the center of the bottom surface of the packaging body, first bonding pads in an L shape are arranged at four corners of the bottom surface of the packaging body, and second bonding pads in n rectangles are distributed between two adjacent first bonding pads at equal intervals; the two ends of the first bonding pad are respectively connected with the two adjacent sides of the packaging body, the first bonding pad is bent close to the central bonding pad, and a locking glue gap part is arranged between the first bonding pad and the two adjacent sides of the bottom surface of the packaging body in a surrounding mode. The utility model discloses well electrically conductive pad integrate dense high, the first pad that is the L font not only can effectively reduce the length of one-way dimension to avoid taking place the short circuit between the electrically conductive pad, can also effectively ensure the overcurrent ability of first pad, in addition, the lock that forms between first pad and the packaging body glues clearance portion and can effectively improve the stability of structure between first pad and the packaging body.

Description

High-density QFN (quad Flat No lead) packaging structure

Technical Field

The utility model relates to an electronic component's packaging structure specifically discloses a high density QFN packaging structure.

Background

QFN (Quad Flat No-lead package), one of the surface mount packages, is known. The surface mount technology is a circuit mounting technology in which a leadless or short-lead surface mount device is mounted on the surface of a circuit board or other substrate and is soldered and assembled by a method such as reflow soldering or dip soldering.

The QFN packaging structure is square or rectangular, a large-area exposed bonding pad for heat conduction is arranged on the bottom surface of the packaging body, and a conductive bonding pad for realizing electrical connection is arranged around the periphery of the package of the large bonding pad. Among the prior art, the bottom surface periphery of packaging body is provided with a plurality of electrically conductive pads all around, and in order to avoid appearing the short circuit scheduling problem, electrically conductive pad avoids four corners settings of packaging body bottom surface, and QFN packaging structure's space utilization is low, integrates the degree lowly.

SUMMERY OF THE UTILITY MODEL

Therefore, it is necessary to provide a high-density QFN package structure, which has high integration density of conductive pads and can effectively avoid short circuit between the conductive pads, in view of the problems in the prior art.

In order to solve the prior art problem, the utility model discloses a high-density QFN packaging structure, which comprises a packaging body, wherein the center of the bottom surface of the packaging body is provided with a central bonding pad, four corners of the bottom surface of the packaging body are respectively provided with a first bonding pad in an L shape, n rectangular second bonding pads are distributed between two adjacent first bonding pads at equal intervals, and n is an integer greater than 1;

the two ends of the first bonding pad are respectively connected with the two adjacent sides of the packaging body, the first bonding pad is bent close to the central bonding pad, and a locking glue gap part is arranged between the first bonding pad and the two adjacent sides of the bottom surface of the packaging body in a surrounding mode.

Furthermore, the corner of the glue locking gap part close to the central bonding pad is provided with a conductive strengthening part, and the conductive strengthening part and the first bonding pad are of an integrally formed structure.

Furthermore, the area of the glue locking gap part is S, the area of the conductive strengthening part is P, and P is more than or equal to 0.2S and less than or equal to 0.5S.

Furthermore, the conductive strengthening part is in a right-angle sector shape.

Furthermore, one end of the second bonding pad close to the central bonding pad is provided with a reinforcing notch.

Further, a distance between the first pad and the adjacent second pad is D, and a distance between two adjacent second pads is also D, where D is D.

Furthermore, D is more than or equal to 0.2mm and less than or equal to 0.5 mm.

Further, n is 3 and D is 0.4 mm.

The utility model has the advantages that: the utility model discloses a high density QFN packaging structure, add four first pads in four corners of packaging body bottom surface, the density of integrating of electrically conductive pad is high among the overall structure, the first pad that is the L font not only can effectively reduce the length of one-way dimension, thereby avoid taking place the short circuit between the electrically conductive pad, can also effectively ensure the overcurrent ability of first pad, in addition, the lock that forms between first pad and the packaging body glues clearance portion and can effectively improve the stability of structure between first pad and the packaging body, thereby effectively avoid first pad to drop.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic structural diagram of another embodiment of the present invention.

The reference signs are: the package body 10, the central pad 11, the first pad 12, the locking glue gap portion 121, the conductive reinforcing portion 122, the second pad 13, and the reinforcing notch 131.

Detailed Description

For further understanding of the features and technical means of the present invention, as well as the specific objects and functions attained by the present invention, the present invention will be described in further detail with reference to the accompanying drawings and detailed description.

Refer to fig. 1 and 2.

The embodiment of the utility model discloses high density QFN packaging structure, as shown in FIG. 1, including packaging body 10, packaging body 10's bottom surface center is equipped with central pad 11, central pad 11 generally is the ground connection pad, packaging body 10's bottom surface four corners all is equipped with one and is the first pad 12 of L font, the first pad 12 of L font can ensure to have sufficient interval between each conductive pad when guaranteeing sufficient area, can avoid taking place the short circuit between the conductive pad, equidistant distribution has the second pad 13 of n rectangles between two adjacent first pads 12, central pad 11, first pad 12 and second pad 13 are all not contacted each other, n is the integer that is greater than 1, first pad 12 and second pad 13 all are used as the IO port;

two ends of the first pad 12 are respectively connected with two adjacent sides of the package body 10, the first pad 12 is bent close to the central pad 11, that is, the tip of the first pad 12 points to the central pad 11, and a locking glue gap portion 121 is surrounded between the first pad 12 and two adjacent sides of the bottom surface of the package body 10.

The utility model adds the first bonding pad 12 structure at four corners of the bottom surface of the packaging body 10, which can effectively expand the I/O port of the semiconductor device to form a high-density structure, and can effectively meet the functional requirement of high-density integration; the L-shaped first bonding pad 12 not only can effectively shorten the length of a single dimension, ensure that the package 10 does not need to increase extra volume, but also can avoid short circuit, and the area of the first bonding pad 12 is large enough, so that the overcurrent capacity of the first bonding pad 12 can be effectively ensured; in addition, the first pad 12 can effectively hook the adhesive locking gap portion 121, so that the structural stability between the first pad 12 and the package body 10 is effectively improved, and the first pad 12 is prevented from falling off.

In the embodiment, as shown in fig. 2, a conductive reinforcement portion 122 is disposed at a corner of each glue locking gap portion 121 close to the central pad 11, the conductive reinforcement portion 122 and the first pad 12 are in an integrally formed structure, by increasing the area of the first pad 12, it can be ensured that the pad has good electrical properties, and the diameter of an inner circle of the conductive structure formed by the first pad 12 and the conductive reinforcement portion 122 can be effectively increased, so as to ensure that a circular welding space with a sufficiently large diameter is provided for solder paste during welding, which not only can improve welding stability, but also can simplify welding operation, and it is not necessary to write L-shaped characters along the first pad 12 during welding.

Based on the above embodiment, the area of the glue locking gap portion 121 is S, the area of the conductive reinforcing portion 122 is P, and P is greater than or equal to 0.2S and less than or equal to 0.5S, so that sufficient space is left in the glue locking gap portion 121, and the effect of stable hook position between the first pad 12 and the package body 10 is ensured.

Based on the above embodiment, the conductive reinforcing part 122 is in the shape of a right-angled sector, which can increase the diameter of the inscribed circle of the conductive structure formed by the first pad 12 and the conductive reinforcing part 122 to the maximum, and simultaneously can effectively ensure that the remaining space of the glue locking gap part 121 is large enough, and ensure the hook position fixing effect of the first pad 12.

In this embodiment, the reinforcing notch 131 is disposed at one end of the second pad 13 close to the central pad 11, and the stability of the connection structure between the second pad 13 and the package 10 can be effectively improved by the reinforcing notch 131.

In this embodiment, the distance between the first pad 12 and the adjacent second pad 13 is D, the distance between two adjacent second pads 13 is also D, and D is D, and preferably, the width of the second pad 13 is also D.

Based on the above embodiment, D is more than or equal to 0.2mm and less than or equal to 0.5 mm.

Based on the above embodiment, where n is 3 and D is 0.4mm, the package structure for QFN2020, i.e., the bottom surface of the package body 10, is provided with four first pads 12 and twelve second pads 13.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A high-density QFN packaging structure comprises a packaging body (10), wherein a central bonding pad (11) is arranged at the center of the bottom surface of the packaging body (10), and the high-density QFN packaging structure is characterized in that four corners of the bottom surface of the packaging body (10) are respectively provided with an L-shaped first bonding pad (12), n rectangular second bonding pads (13) are distributed between every two adjacent first bonding pads (12) at equal intervals, and n is an integer greater than 1;

the two ends of the first bonding pad (12) are respectively connected with two adjacent sides of the packaging body (10), the first bonding pad (12) is close to the central bonding pad (11) to be bent, and a locking glue gap part (121) is arranged between the first bonding pad (12) and two adjacent sides of the bottom surface of the packaging body (10) in a surrounding mode.

2. The high-density QFN package structure as claimed in claim 1, wherein the corner of the locking glue gap portion (121) near the central pad (11) is provided with a conductive reinforcement portion (122), and the conductive reinforcement portion (122) and the first pad (12) are integrally formed.

3. The QFN package structure as claimed in claim 2, wherein the area of the underfill clearance portion (121) is S, the area of the conductive reinforcement portion (122) is P, and 0.2S ≦ P ≦ 0.5S.

4. The QFN package structure as claimed in claim 3, wherein the conductive reinforcement (122) is in the shape of a right-angled sector.

5. A high-density QFN package structure according to claim 1, wherein the second pad (13) is provided with a reinforcement notch (131) at an end close to the central pad (11).

6. A high-density QFN package structure according to claim 1, wherein a distance between the first pad (12) and the adjacent second pad (13) is D, and a distance between the adjacent second pads (13) is also D, D ═ D.

7. The QFN package structure as claimed in claim 6, wherein D is 0.2mm ≤ D ≤ 0.5 mm.

8. The QFN package structure of claim 6, wherein n is 3 and D is 0.4 mm.