CN216450640U

CN216450640U - Photoelectric coupler packaging structure

Info

Publication number: CN216450640U
Application number: CN202122905715.XU
Authority: CN
Inventors: 陈仕财; 詹伟彬; 王钧毅; 朱海刚; 刘红盛
Original assignee: Xiamen Jiuhongxin Photoelectric Co ltd
Current assignee: Xiamen Jiuhongxin Photoelectric Co ltd
Priority date: 2021-11-24
Filing date: 2021-11-24
Publication date: 2022-05-06
Anticipated expiration: 2031-11-24

Abstract

The application relates to the field of semiconductors, in particular to a photoelectric coupler packaging structure which comprises a substrate, wherein the front surface of the substrate is used for mounting a chip; the back surface of the substrate is provided with pins; the pins are conductive membranes; the pin is provided with a limiting groove. This application has the degree of combination that improves optoelectronic coupler and product PCB board to compromise the effect that optoelectronic coupler structure is small and exquisite.

Description

Photoelectric coupler packaging structure

Technical Field

The application relates to the field of semiconductors, in particular to a photoelectric coupler packaging structure.

Background

A photocoupler is a device for transmitting an electrical signal through light as a medium, and generally, a light emitter and a light receiver are packaged in the same package. When the input end is electrified, the light emitter emits light, and the light receiver receives the light, then the light generates photocurrent which flows out from the output end, thereby realizing 'electro-optic-electrical' control.

Referring to fig. 1, a cross-sectional view of a packaged photocoupler in the related art is shown. Photoelectric coupler mainly includes base plate 1, emitting chip 2, receive optical chip 3, interior plastic envelope glue 4 and outer plastic envelope glue 5, emitting chip 2 and receive optical chip 3 all are fixed in the front of base plate 1, the reverse side of base plate 1 is provided with the pin 6 of connecting in emitting chip 2 and the metal film of receiving optical chip 3, interior plastic envelope glue 4 is the epoxy that has the light transmissivity, interior plastic envelope glue 4 is with emitting chip 2, receive optical chip 3 and partial base plate 1 cladding back, encapsulate with outer plastic envelope glue 5 that has infrared light reflection nature, make the photoelectric coupler structure of production small and exquisite, reduce photoelectric coupler pin 6 overlength and cause the effect of unnecessary impedance. When the photoelectric coupler is installed on a PCB of a product, firstly, solder paste is coated at a designated position on the PCB of the product, then, the pin 6 on the reverse side of the substrate 1 is placed at the designated position, and the solder paste is solidified through reflow soldering, so that the photoelectric coupler can be welded on the PCB of the product.

In view of the above-mentioned related art, the inventor believes that the photocoupler produced by the substrate has a small and exquisite structure, but after the photocoupler is fixed at a designated position on the PCB of the product, because only the pin on the reverse side of the substrate is combined with the solder paste, in the subsequent process, the photocoupler is collided and easily peels off the PCB of the product, and the degree of coupling between the photocoupler and the PCB of the product is poor.

SUMMERY OF THE UTILITY MODEL

In order to improve the coupling degree of optoelectronic coupler and product PCB board to compromise optoelectronic coupler's small and exquisite structure, this application provides an optoelectronic coupler packaging structure.

The application provides a photoelectric coupler packaging structure adopts following technical scheme:

a photoelectric coupler packaging structure comprises a substrate body, a chip and a packaging cover, wherein the front surface of the substrate body is used for mounting a chip; the back surface of the substrate body is provided with pins; the pins are conductive membranes; the pin is provided with a limiting groove.

By adopting the technical scheme, when the photoelectric coupler is welded on the PCB of the product, an operator firstly coats the designated position of the PCB of the product with the solder paste, then places the pins on the reverse side of the substrate body on the designated position of the PCB of the product for reflow soldering, the solder paste is solidified, the pins on the reverse side of the substrate body are combined with one part of the solder paste, and the other part of the solder paste is condensed in the limiting groove. Through the spacing groove, when photoelectric coupler received to collide with, spacing groove and the tin cream that condenses restrict photoelectric coupler in the slip on product PCB board surface to reduce photoelectric coupler's pin and the risk of product PCB board separation, and then improve photoelectric coupler and product PCB board's degree of coupling, the pin of conductive diaphragm compromises photoelectric coupler small and exquisite effect simultaneously.

Optionally, the limiting groove penetrates through the front surface and the back surface of the substrate body; and a metal film layer is arranged on the inner wall of the limiting groove.

Through adopting above-mentioned technical scheme, at the reflow soldering in-process, the tin cream melts, and metal film layer provides the attachment position for melting tin, increases and climbs the tin height, improves photoelectric coupler and the associativity of molten tin to after molten tin solidifies, improve photoelectric coupler and the associativity of product PCB board.

Optionally, a connecting layer is disposed on the front surface of the substrate body; the connecting layer is used for connecting the chips; the metal film layer is used for connecting the connecting layer and the pins so that the pins are electrically connected to the connecting layer.

Through adopting above-mentioned technical scheme, on the one hand, metal thin film layer plays electrically conductive effect, makes the electric current that flows to the pin flow to the articulamentum smoothly to realize the effect of the electric current flow direction chip that flows to the pin, on the other hand metal thin film layer is connected articulamentum, pin, reduces the risk of pin and base plate body separation, improves the stability of being connected of pin and base plate body.

Optionally, the plastic packaging material further comprises an outer plastic packaging layer; the front surface of the substrate body is provided with a glue injection groove; and the glue injection groove is used for filling the outer plastic packaging layer.

Through adopting above-mentioned technical scheme, the introduction in glue injection groove reduces outer plastic envelope layer and receives the risk that external force moved relatively the base plate body under the effect, improves the stability of being connected of outer plastic envelope layer and base plate body, improves photoelectric coupler's life.

Optionally, the plastic packaging material further comprises an inner plastic packaging layer; the outer plastic packaging layer wraps the inner plastic packaging layer; the edge of the inner plastic package layer, which is far away from the substrate body, is provided with arc transition so as to form an optical reflecting surface.

Through adopting above-mentioned technical scheme, the setting of interior plastic envelope layer circular arc transition for the light that optoelectronic coupler's luminous chip sent, through the reflection of optics plane of reflection, improve optoelectronic coupler's the receipts light beam of receiving the light chip, thereby improve optoelectronic coupler's photoelectric conversion ratio.

Optionally, the substrate body is provided with an epoxy resin layer; the epoxy resin layer is used for connecting and fixing the outer plastic packaging layer and the inner plastic packaging layer.

Through adopting above-mentioned technical scheme, the setting of epoxy layer reduces interior plastic envelope layer or outer plastic envelope layer and the risk of base plate body separation in the processing procedure, improves the stability of being connected of interior, outer plastic envelope layer and base plate body.

Optionally, an anti-slip layer is arranged on the reverse side of the substrate body; the thickness of the anti-slip layer is larger than or equal to that of the pins.

Through adopting above-mentioned technical scheme, place the assigned position of reflow soldering on the product PCB board at the pin of base plate body reverse side, when the tin cream melts, there is the risk of removal in the base plate body, and the introduction of skid resistant course reduces the risk that the base plate body removed when the tin cream melts, improves the hookup location accuracy of optoelectronic coupler and product PCB board.

Optionally, the anti-slip layer is a solder resist ink layer with a frosted surface.

Through adopting above-mentioned technical scheme, hinder the setting on welding the printing ink layer, reduce the risk that the skid resistant course is burnt out by the melting tin of high temperature, reduce the skid resistant course simultaneously and have the adnexed risk of tin to reduce the risk that the skid resistant course attracts the position department that is located the pin to melt tin, provide and make pin position department leave sufficient tin and product PCB and combine, improve the welding stability of optoelectronic coupler and product PCB board.

In summary, the present application includes at least one of the following beneficial technical effects:

through the limiting groove, when the photoelectric coupler is collided, the limiting groove and the condensed solder paste limit the sliding of the photoelectric coupler on the surface of the PCB of the product, so that the risk of separating the pin of the photoelectric coupler from the PCB of the product is reduced, the degree of combination of the photoelectric coupler and the PCB of the product is further improved, and meanwhile, the pin of the conductive diaphragm has the effect of small and exquisite structure of the photoelectric coupler;

the metal film layer provides an attachment position for molten tin, increases the tin climbing height and improves the combination degree of the photoelectric coupler and the molten tin, so that the combination degree of the photoelectric coupler and a PCB (printed circuit board) product is improved after the molten tin is solidified;

through the anti-skidding layer, reduce the risk that the base plate body removed when the tin cream melts, improve the hookup location accuracy of optoelectronic coupler and product PCB board.

Drawings

Fig. 1 is a sectional view of a packaged photocoupler in the related art.

Fig. 2 is a schematic overall structure diagram of an embodiment of the present application.

Fig. 3 is an exploded view of the overall structure of an embodiment of the present application.

Fig. 4 is a schematic view illustrating a position of the anti-slip layer on the reverse side of the substrate body according to the embodiment of the present application.

Description of reference numerals: 1. a substrate; 2. a light emitting chip; 3. a light receiving chip; 4. internal plastic sealing glue; 5. external plastic sealing glue; 6. a pin; 7. a substrate body; 71. an epoxy resin layer; 72. a connecting layer; 73. injecting glue groove; 74. a limiting groove; 75. an anti-slip layer; 8. an inner plastic packaging layer; 81. arc transition; 9. an outer plastic sealing layer; 10. a metal film layer.

Detailed Description

The present application is described in further detail below with reference to figures 1-4.

Referring to fig. 1, the photoelectric coupler mainly includes a substrate 1, a light emitting chip 2, a light receiving chip 3, an inner molding compound 4 and an outer molding compound 5, wherein the light emitting chip 2 and the light receiving chip 3 are both fixed on the front surface of the substrate 1, and a pin 6 connected to a metal film of the light emitting chip 2 and the light receiving chip 3 is fixed on the back surface of the substrate 1. When the photoelectric coupler is welded on the PCB of the product in the follow-up process, the designated position on the PCB of the product is coated with the solder paste, then the pin 6 on the reverse side of the substrate 1 is placed at the designated position, and the solder paste is solidified through reflow soldering, so that the photoelectric coupler can be welded on the PCB of the product.

The embodiment of the application discloses photoelectric coupler packaging structure to improve the coupling degree of photoelectric coupler and product PCB board, and compromise photoelectric coupler's small and exquisite structure.

Referring to fig. 2 and 3, a photoelectric coupler packaging structure includes a substrate body 7, an inner plastic-sealed layer 8 and an outer plastic-sealed layer 9, wherein the substrate body 7 is a PCB support coated by an epoxy resin layer 71, and the substrate body 7 is used for bonding and fixing a light-emitting chip 2 and a light-receiving chip 3. The inner plastic package layer 8 is used for coating the light-emitting chip 2 and the light-receiving chip 3, and the inner plastic package layer 8 is made of epoxy resin with light-transmitting materials. The outer plastic package layer 9 is used for coating the inner plastic package layer 8, and the outer plastic package layer 9 is made of epoxy resin with infrared light reflection property.

Referring to fig. 3, specifically, the front surface of the substrate body 7 is provided with a connection layer 72 for connecting the light emitting chip 2 and the light receiving chip 3, and the connection layer 72 is a copper foil after etching the PCB support. Two glue injection grooves 73 are formed in the front surface of the substrate body 7, and the two glue injection grooves 73 are respectively located on the edges, far away from each other, of the substrate body 7. The glue injection groove 73 is used for filling the outer plastic package layer 9, so that the risk of relative sliding between the outer plastic package layer 9 and the substrate body 7 is reduced, and meanwhile, the connection stability between the outer plastic package layer 9 and the substrate body 7 is improved due to the design of the epoxy resin layer 71.

Referring to fig. 3 and 4, the back surface of the substrate body 7 has four leads 6, and the leads 6 are copper foils etched on the PCB board support, like the connection layer 72. Four limiting grooves 74 extending to the front surface of the substrate body 7 are formed in the back surface of the substrate body 7, and the four limiting grooves 74 correspond to the four pins 6 one by one. The limiting groove 74 penetrates the surface of the pin 6 away from the substrate body 7, and a groove wall of the limiting groove 74 extends to a side wall of the substrate body 7.

Referring to fig. 4, two of the four limiting grooves 74 are respectively located on the side walls of the substrate body 7 that face away from each other. And the two limit grooves 74 on the side wall of the substrate body 7 are defined as a set of limit grooves 74, i.e. there are two sets of limit grooves 74 on the substrate body 7. The anti-skid layer 75 is fixedly bonded in the area, between the two sets of limiting grooves 74, of the reverse side of the substrate body 7, the anti-skid layer 75 is a solder-resistant ink layer with a frosted surface, and the thickness of the anti-skid layer 75 is larger than or equal to that of the pins 6. In other embodiments, the anti-slip layer 75 may be an epoxy layer with a frosted surface, or may be a heat conductive silicone pad.

Referring to fig. 3 and 4, the metal thin film layer 10 is bonded and fixed to the bottom of the stopper groove 74, and the metal thin film layer 10 may be a copper foil, a gold foil, or a silver foil. Metal thin film layer 10 connects pin 6 and connection layer 72 so that pin 6 is electrically connected to connection layer 72, thereby achieving an effect that current flowing to pin 6 flows to connection layer 72.

Referring to fig. 3, it should be noted that the edge of the inner molding layer 8 away from the substrate body 7 is provided with an arc transition 81 to form an optical emission surface, so that the light beam emitted by the light emitting chip 2 is reflected by the optical reflection surface to increase the light receiving beam of the light receiving chip 3, thereby increasing the photoelectric conversion ratio of the photoelectric coupler. It should be noted that by changing the curvature of the circular arc transition 81, the light receiving beam of the light receiving chip 3 can be changed accordingly, so as to realize different photoelectric conversion ratios of the photoelectric coupler.

The implementation principle of the photoelectric coupler packaging structure in the embodiment of the application is as follows: when the photoelectric coupler is welded on a PCB of a product, an operator firstly coats solder paste on a specified position of the PCB of the product, then places the pins 6 on the reverse side of the substrate body 7 on the specified position of the PCB of the product for reflow soldering, the solder paste is solidified, the pins 6 on the reverse side of the substrate body 7 are combined with part of the solder paste, and the other part of the solder paste is condensed on the surface of the metal film layer 10. When photoelectric coupler received the clash, spacing groove 74 and the tin cream that condenses restricted photoelectric coupler in the slip on product PCB board surface to improve photoelectric coupler and product PCB board's degree of combination, the pin 6 of conductive diaphragm compromises the effect that photoelectric coupler structure is small and exquisite simultaneously.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. A photoelectric coupler packaging structure is characterized in that: comprises a substrate body (7) with a front surface for mounting a chip; the reverse side of the substrate body (7) is provided with pins (6); the pins (6) are conductive membranes; the pin (6) is provided with a limiting groove (74).

2. A photoelectric coupler packaging structure according to claim 1, wherein: the limiting groove (74) penetrates through the front surface and the back surface of the substrate body (7); the inner wall of the limiting groove (74) is provided with a metal film layer (10).

3. A photoelectric coupler packaging structure according to claim 2, wherein: the front surface of the substrate body (7) is provided with a connecting layer (72); the connecting layer (72) is used for connecting chips; the metal film layer (10) is used for connecting the connecting layer (72) and the pins (6) so that the pins (6) are electrically connected with the connecting layer (72).

4. A photoelectric coupler packaging structure according to claim 1, wherein: also comprises an outer plastic packaging layer (9); the front surface of the substrate body (7) is provided with a glue injection groove (73); the glue injection groove (73) is used for filling the outer plastic packaging layer (9).

5. A photoelectric coupler packaging structure according to claim 4, wherein: also comprises an inner plastic package layer (8); the outer plastic packaging layer (9) wraps the inner plastic packaging layer (8); the edge of the inner plastic packaging layer (8) far away from the substrate body (7) is provided with an arc transition (81) to form an optical reflection surface.

6. A photoelectric coupler packaging structure according to claim 5, wherein: the substrate body (7) is provided with an epoxy resin layer (71); the epoxy resin layer (71) is used for connecting and fixing the outer plastic packaging layer (9) and the inner plastic packaging layer (8).

7. A photoelectric coupler packaging structure according to any one of claims 1 to 6, wherein: the reverse side of the substrate body (7) is provided with an anti-skid layer (75); the thickness of the anti-slip layer (75) is larger than or equal to that of the pins (6).

8. A photoelectric coupler packaging structure according to claim 7, wherein: the anti-slip layer (75) is a solder resist ink layer with a frosted surface.