CN-122000757-A - Switching terminal, POP (POP) laminated packaging structure and packaging method thereof

CN122000757ACN 122000757 ACN122000757 ACN 122000757ACN-122000757-A

Abstract

The application belongs to the technical field of stacked welding packaging of switching power supplies, and provides a switching terminal, a POP stacked packaging structure and a packaging method thereof. The transfer terminal disclosed by the application has the advantages that the integrated arch-shaped connecting sections and the welding expansion sections are lifted to be in a suspended state through the supporting legs, a stable supporting structure is formed, the integral gravity center is reduced, the problem that the existing terminal is easy to topple before reflow soldering after mounting is solved, a stable foundation is provided for subsequent packaging processing, the transfer terminal separates the welding expansion sections at two sides through the arch-shaped connecting sections, the arch-shaped connecting sections are removed after plastic packaging, the two welding expansion sections at two sides are mutually disconnected and exposed, the effective separation and pin extension reconstruction of a welding area are realized, the welding communication requirements of different pin ends of an upper-layer component are adapted, and the problem of poor matching of upper-layer bonding pads and lower-layer bonding pads is effectively solved.

Inventors

LI YANQIANG
ZHANG JINCHENG

Assignees

广州辰微电子科技有限公司

Dates

Publication Date: 20260508
Application Date: 20251230

Claims (10)

1. The switching terminal is processed by metal conductor materials and is characterized by comprising an arch-shaped connecting section, a welding expansion section and supporting feet; The welding expansion section is a group of horizontal plane structures formed by downwards bending two ends of the arched connecting section which are constructed by extending along the horizontal direction, and the relative height of the bottom end surface of the arched connecting section in the vertical direction is higher than the top end surfaces of the two welding expansion sections; the supporting legs are of a group of vertical surface structures formed by downwards bending one side, away from the arched connecting sections, of each welding expansion section, the arched connecting sections and the welding expansion sections are lifted to be in a suspended state from below, and the supporting legs are restrained below the arched connecting sections and the welding expansion sections to form a spacing gap.
2. The adapter terminal according to claim 1, wherein the support leg is configured to extend from one end of the welding expansion section in a length direction of the welding expansion section, and an extension length of the support leg in a horizontal direction is smaller than an extension length of the welding expansion section.
3. The adapter terminal according to claim 2, wherein a leg is also bent downward at a side edge of the welding expansion section facing away from the supporting leg; The projection of the lap on the vertical direction is perpendicular to the supporting leg, and the extending height of the lap along the vertical direction is smaller than that of the supporting leg.
4. A transit terminal as defined in claim 3 wherein, the transit terminal is made from a sheet metal stock material by etching or sheet metal machining.
5. The POP laminated packaging structure comprises a carrier plate, a first-layer component, a surface insulating device and an upper-layer component, wherein the first-layer component and the surface insulating device are assembled on the carrier plate through welding of a plurality of bonding pads arranged on the carrier plate, and the upper-layer component is assembled on the surface insulating device in a laminated manner, and the POP laminated packaging structure is characterized in that the upper-layer component is supported and overlapped on the surface insulating device through the switching terminal according to claim 1 and is electrically communicated; The supporting feet are arranged on the same carrier plate in a crossing manner, and the supporting feet are welded and fixed with the bonding pads of the carrier plate; The carrier plate, the first-layer component, the surface insulation component and the switching terminal are integrally molded, the arched connecting sections are processed and removed to enable the welding expansion sections on the two sides to be mutually disconnected, and pins of the upper-layer component are welded and fixed with top end faces of the two welding expansion sections respectively.
6. The POP laminated packaging structure comprises a carrier plate, a first-layer component, a surface insulating device and an upper-layer component, wherein the first-layer component and the surface insulating device are assembled on the carrier plate through welding of a plurality of bonding pads arranged on the carrier plate, and the upper-layer component is assembled on the surface insulating device in a laminated manner, and the POP laminated packaging structure is characterized in that the upper-layer component is supported and overlapped on the surface insulating device through the switching terminal according to any one of claims 2 to 4 and is electrically communicated; The supporting feet are arranged on the same carrier plate in a crossing manner, and the supporting feet are welded and fixed with the bonding pads of the carrier plate; The carrier plate, the first-layer component, the surface insulation component and the switching terminal are integrally molded, the arched connecting sections are processed and removed to enable the welding expansion sections on the two sides to be mutually disconnected, and pins of the upper-layer component are welded and fixed with top end faces of the two welding expansion sections respectively.
7. The POP package on package structure of claim 6, wherein one end of the soldering expansion section extends above the surface insulation device, or the clip is mounted on top of the surface insulation device.
8. A packaging method of a POP stack package structure, applied to the packaging implementation of the POP stack package structure according to claim 7, the method comprising the steps of: S1, brushing tin on each bonding pad and a welding area of a carrier plate, and attaching a first-layer component and a surface insulation component; S2, erecting a switching terminal on the carrier plate, wherein supporting legs of the switching terminal are correspondingly arranged on a bonding pad or a welding area of the carrier plate, one end of the welding expansion section extends to the upper side of the surface insulation device, or the supporting legs are erected on the top of the surface insulation device to form an auxiliary support; S3, carrying the first-layer component, the surface insulation component and the transfer terminal by the carrier plate for reflow soldering; s4, carrying out integral plastic package on the carrier plate, the first-layer component, the surface insulation component and the transfer terminal; S5, grinding the top end face of the welding expansion section serving as a reference surface, and processing and removing an arch-shaped connecting section part of the switching terminal to enable the welding expansion sections on two sides of the switching terminal to be mutually disconnected and expose the top end face; S6, brushing tin on the top end face of the exposed welding expansion section, and mounting upper-layer components, so that pins of the upper-layer components are correspondingly erected on the top end face of the welding expansion section; S7, carrying the first-layer component, the surface insulation component, the switching terminal and the upper-layer component by the carrier plate to carry out secondary reflow soldering.
9. The packaging method of the POP stack packaging structure according to claim 8, wherein the surface insulation device is DFN, QFN, SOT or an SOP device, and the upper component is a chip capacitor, a resistor, an inductor, a DFN device, an FC chip or a second carrier plate.
10. The POP laminated packaging structure comprises a carrier plate, a first-layer component, a surface insulating device and an upper-layer component, wherein the first-layer component and the surface insulating device are assembled on the carrier plate through welding of a plurality of bonding pads arranged on the carrier plate, and the upper-layer component is assembled on the surface insulating device in a laminated manner, and the POP laminated packaging structure is characterized in that the upper-layer component is supported and overlapped on the surface insulating device through the switching terminal according to any one of claims 1 to 4 and is electrically communicated; The two support legs of the switching terminal are arranged on two adjacent carrier plates in a straddling mode, each support leg is welded and fixed with a bonding pad of each carrier plate, and two groups of pins of the upper-layer component are welded and fixed with the top end faces of the welding expansion sections of the two adjacent switching terminals respectively.

Description

Switching terminal, POP (POP) laminated packaging structure and packaging method thereof Technical Field The application belongs to the technical field of stacked welding packaging of switching power supplies, and particularly relates to a transfer terminal, a POP stacked packaging structure and a packaging method thereof. Background Along with the rapid development of electronic products in the directions of miniaturization and high-density integration, POP (Package on Package) stack packaging technology has become one of core technical schemes for improving packaging integration density because of being capable of greatly improving the space utilization rate of a module power supply. When the POP stack packaging technology is applied, a plurality of common surface insulation devices such as DFN, QFN, SOT, SOP are assembled on a carrier plate in the industry, and the devices generally only have a planar bonding pad or a short pin structure and cannot directly provide electrical connection points in the vertical direction. In order to realize stable connection and support of the upper-layer components, the bottom-layer carrier plate and the surface insulation components, metal terminals are commonly adopted in the industry as intermediate switching structures, and the support positioning of the upper-layer components and the electrical communication of upper-layer and lower-layer circuits are completed through the structures so as to meet the core requirements of laminated integrated layout. However, when the existing metal terminals are adapted to the above-mentioned packaging scene, a plurality of defects which are difficult to overcome are gradually exposed, firstly, the positions and the areas of bonding pads of surface insulation devices are obviously different, the pin layout of upper-layer components is also various, the existing metal terminals are single in structure, the extension and the reconstruction of pins cannot be realized, the problem of poor matching between upper-layer bonding pads and lower-layer bonding pads and terminals is easily caused, the stability of electric connection is affected, secondly, the space limitation of a carrier plate and a board is carried out, the bonding pads which can be allocated to the metal terminals are limited, the traditional metal terminals are of cylindrical structures, the gravity center is higher, stable support is difficult to form in the processing process after tin brushing and mounting and before reflow soldering fixing, the dumping is extremely easy to occur, and the production yield is seriously affected. Disclosure of Invention The application provides a transfer terminal, a POP laminated packaging structure and a packaging method thereof, which are used for solving the problems that the existing switching power supply product is affected by the differences of the layout, the area of a bonding pad, the position and the like of upper and lower devices, the unmatched welding area is caused when metal terminals are used for interconnection, and the terminals are easy to topple. In one aspect, a transfer terminal is provided that is fabricated from a metallic conductor material and includes an arcuate connecting section, a welding expansion section, and support legs. The welding expansion sections are a group of horizontal structures formed by downwards bending two ends of an arch-shaped connecting section which is formed by extending along the horizontal direction, the relative height of the bottom end face of the arch-shaped connecting section in the vertical direction is higher than the top end faces of the two welding expansion sections, the supporting feet are a group of vertical structures formed by downwards bending one side, away from the arch-shaped connecting section, of each welding expansion section, the supporting feet lift the arch-shaped connecting section and the welding expansion section from below to be in a suspended state, and the supporting feet are restrained below the arch-shaped connecting section and the welding expansion section to form a space. Further, the support leg extends from one end of the welding expansion section along the length direction of the welding expansion section, and the extending length of the support leg in the horizontal direction is smaller than that of the welding expansion section. Furthermore, the welding expansion section is also provided with a foot at one side edge deviating from the supporting foot in a downward bending mode, the projection of the foot in the vertical direction is perpendicular to the supporting foot, and the extending height of the foot in the vertical direction is smaller than that of the supporting foot. Further, the adapter terminal is made of a sheet metal raw material by etching or sheet metal working. In one scheme, the POP laminated packaging structure comprises a carrier plate, a first-layer component, a surface insulating component and an upper-layer component, where