CN220821555U

CN220821555U - QFN packaging transition structure of sensor chip

Info

Publication number: CN220821555U
Application number: CN202322559210.1U
Authority: CN
Inventors: 宋超超; 王勇; 李虎
Original assignee: Shandong Manxin Electronic Technology Co ltd
Current assignee: Shandong Manxin Electronic Technology Co ltd
Priority date: 2023-09-20
Filing date: 2023-09-20
Publication date: 2024-04-19
Anticipated expiration: 2033-09-20

Abstract

The utility model relates to a structure of an integrated circuit with a sensor, in particular to a QFN packaging transition structure of a sensor chip. The bare chip, the lead frame and the pins are connected with the film, the bare chip, the lead frame and the pins face the film through the bonding layer, and the bare chip, the lead frame and the pins face the film. The utility model discloses the course of working of sensor class or similar chip that not only can simplify can also reduce cost to the yield of product has been improved.

Description

QFN packaging transition structure of sensor chip

Technical Field

The utility model relates to a structure of an integrated circuit with a sensor, in particular to a QFN packaging transition structure of a sensor chip.

Background

In some sensor chips, the chip sensing area and the chip bonding pad are located on different surfaces of the chip. Usually, such chips are flip-chip packaged, i.e. the solder joints of the chip are soldered to corresponding pins of the lead frame or the substrate by flip-chip bonding, and the sensing area is exposed on the top surface of the product by a dedicated plastic packaging die, so as to be in contact with the external environment.

Fig. 1 illustrates a typical prior art method of manufacturing a sensor of this type. The sensor SMT is packaged on a PCB (or a system board) by arranging a through hole 2 on the PCB or the system board 1, and the through hole 2 is just aligned to a chip bottom surface sensing area of a sensor chip 3 exposed outside after the packaging of the sensor SMT on the PCB (or the system board) is completed. In addition, the bonding pads of such an integrated block are often provided on the lower surface of the sensor chip 3, and flip-chip bonding is required during processing, which not only brings difficulty to processing and increases production cost, but also easily reduces yield.

Disclosure of Invention

The utility model aims at: a sensor chip QFN packaging transition structure capable of simplifying operation and having low cost is designed.

The utility model comprises at least one processing unit, each processing unit comprises a lead frame and a bare core with an induction area on the upper surface, a group of pins are connected to the lead frame, the bare core also comprises a film with an adhesive layer on one surface, a welding pad on the bare core is arranged on the lower surface far away from the film, the bare core, the lead frame and the pins are connected with the film through the adhesive layer, and the induction area of the bare core faces the film.

Further, the films are located on the same plane, and the pins and the upper surface of the bare core are arranged on the same surface under the action of the films.

Further, it comprises at least two processing units, each processing unit being connected to the same film by means of an adhesive layer.

Further, the leads, bare core body and wires are located in the plastic package except the bare core, the upper surfaces of the leads and the lead frame.

Further, the bonding pad on the bare core is connected with the pin through a wire.

The utility model adopts the structure of the film, can protect the sensing area of the sensor chip in the packaging process, and can expose the sensing area of the chip outside after tearing off the high-temperature resistant film after the packaging is finished.

Drawings

FIG. 1 is a schematic diagram of a prior art structure;

FIG. 2 is a top view of a processing unit according to embodiment 1 of the present utility model;

FIG. 3 is a view A-A of FIG. 2;

FIG. 4 is an enlarged view of point B in FIG. 3;

FIG. 5 is a bottom view of embodiment 1 of FIG. 2;

FIG. 6 is a front view of a processing unit of example 2;

FIG. 7 is a cross-sectional view of FIG. 6;

Wherein, 1, a system board, 2, through holes, 3, a sensor chip, 4, a lead frame, 5, pins, 6 and a film, 7, an adhesive layer, 8, bare cores, 9, an induction area, 10, a wire, 11, a plastic package body, 12 and a welding pad.

Detailed Description

Examples

As shown, this embodiment includes a film 6, a lead frame 4, and a set of leads 5 connected to the lead frame 4, and a bare die 8 with a sensing area 9.

Wherein an adhesive layer 7 is provided on one surface of the film 6. During production, the adhesive layer 7 is arranged above the film 6. The film 6 and the adhesive layer 7 may be arranged on a planar mesa so that the film 6 is in a planar state.

The upper surfaces of the lead frame 4 and the leads 5 of the present embodiment, which are located at the upper part in use, face downward at this time and are adhered to the film 6 by the adhesive layer 7. The upper surface of bare core 8 with sensing area 9 is downward, and is connected to film 6 by adhesive layer 7, so that the upper surfaces of lead frame 4, pins 5 and bare core 8 are all downward and on the same plane. The bonding pad 9 on the bare core 8 is located on the lower surface of the bare core 8, and since the bare core 8 of the present embodiment is upside down, the bonding pad 9 thereof is located on the upper surface of the present embodiment. The pads 9 are connected to corresponding pins 5 of the lead frame 4 by wires 10.

Examples

As shown in the figure, this embodiment is a further product based on embodiment 1, and the positions and connection manners of the components in the product that are the same as those in embodiment 1, and are not described here again.

In this embodiment, the plastic package 12 is added to the base of embodiment 1. The plastic package body 12 places the pin 5, bare core 8 main body and wire 6 in the plastic package body 7, and the upper surfaces of the lead frame 1, pin 2 and bare core 8 are still connected with the film 6 through the bonding layer 7.

When the sensor chip is processed by the utility model, a special PCB with holes is not needed, whether the positions of the through holes formed in the PCB correspond to the positions of the sensing areas of the sensor chip or not is not needed, and a film with an adhesive layer is adopted, so that the utility model is not only beneficial to positioning the bare core 8, the lead frame 1 and the pins 2, but also does not need to adopt a flip-chip welding mode, and the film 6 is stripped after the processing is finished. This not only simplifies the processing procedure, but also reduces the cost and improves the yield of the product.

Claims

1. The utility model provides a sensor chip QFN encapsulation transition structure, includes at least one processing unit, and every processing unit includes lead frame (4) and the bare core (8) that the upper surface has sensing area (9), connects a set of pin (5), characterized by on lead frame (4): the bare chip comprises a film (6) with an adhesive layer (7) on one surface, wherein a bonding pad (12) on the bare chip (8) is arranged on the lower surface of the bare chip far away from the film (6), the bare chip (8), a lead frame (4) and pins (5) are connected with the film (6) through the adhesive layer (7), and an induction area (9) of the bare chip (8) faces the film (6).

2. The sensor chip QFN package transition structure of claim 1, wherein: the film (6) is positioned on the same plane, and the upper surfaces of the pins (5) and the bare core (8) are arranged on the same surface under the action of the film (6).

3. The sensor chip QFN package transition structure of claim 1 or 2, wherein: the device comprises at least two processing units, wherein each processing unit is connected with the same film (6) through an adhesive layer (7).

4. The sensor chip QFN package transition structure of claim 3, wherein: the bare core (8), the upper surface of the pin (5) and the lead frame (4) are arranged in the plastic package body (11), and the pin (5), the bare core (8) main body and the lead (10).

5. The sensor chip QFN package transition structure of claim 1 or 2, wherein: the bare core (8), the upper surface of the pin (5) and the lead frame (4) are arranged in the plastic package body (11), and the pin (5), the bare core (8) main body and the lead (10).

6. The sensor chip QFN package transition structure of claim 1 or 2, wherein: the welding pad (12) on the bare core (8) is connected with the pin (5) through a lead (10).