CN220731529U - Planar optocoupler packaging structure - Google Patents

Abstract

The application discloses a planar optocoupler packaging structure and relates to the technical field of optocoupler. The planar optical coupler packaging structure is provided with a first direction and a second direction which are perpendicular to each other, the second direction is an upper-lower interval direction, and the planar optical coupler packaging structure comprises a first bracket, a second bracket, a stack structure and a packaging layer; the second bracket and the first bracket are arranged at intervals along the first direction, and an input end welding area is arranged on the upper surface of the first bracket, which is close to the second bracket; the stack structure comprises a light receiving chip, a light guide structure and a light emitting chip which are sequentially laminated on the upper surface of the second bracket; the light-emitting chip is electrically connected with the input end welding area through the input end bonding wire; the packaging layer wraps the input end welding area and the stack structure; the part of the first bracket provided with the input end welding area protrudes towards the side close to the light emitting chip along the second direction. The support of the first support to the input end bonding wire can be improved, and the purpose of preventing the input end bonding wire from being disconnected is achieved.

Description

Planar optocoupler packaging structure

Technical Field

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

Background

The optocoupler (opticalcoupler equipment), which is also called an optoisolator or an optocoupler, is a device for transmitting an electrical signal by using light as a medium, and generally packages a light emitting chip (such as a light emitting diode LED) and a light receiving chip (such as a photo-sensitive semiconductor tube and a photo-resistor) in the same housing. When the input end is powered on, the light emitting chip emits light, the light receiving chip receives the light to generate photocurrent, and the photocurrent flows out of the output end, so that 'electricity-light-electricity' control is realized. The photoelectric coupler using light as medium to couple the signal of input end to output end has the advantages of small volume, long service life, no contact, strong anti-interference capability, insulation between output and input, unidirectional signal transmission, etc. and can be widely used in digital circuits.

An optocoupler having a MOSFET function is paid more attention, and is often used in power management and the like, for example, as an internal optical relay applied to a charging pile, a transformer, and the like. The traditional packaging structure of the photoelectric coupler with the MOSFET function mainly comprises an upper-lower opposite type photoelectric coupler packaging structure and a planar photoelectric coupler packaging structure.

As shown in fig. 1, the light emitting chip 101 and the light receiving chip 102 of the vertical pair optocoupler package structure 100 are respectively disposed at two ends of the upper and lower brackets, the MOSFET chip 103 is disposed in a non-light receiving area, and the light receiving chip 102 and the light emitting chip 101 are packaged and coated by using an inner molding compound with light transmittance, and the light emitting chip 101 and the light receiving chip 102 need to be coated by an inner molding compound with light transmittance not greater than 25%, so that the light beam of the light emitting chip 101 is greatly reduced, the efficiency of the light receiving chip 102 is poor, and the overall performance of the product is further reduced.

As shown in fig. 2, in the planar optocoupler package structure 200, a stack structure 230 on a second support 220 includes a light receiving chip 231, a light guiding structure 232 and a light emitting chip 233 sequentially stacked on the second support, and the light emitting chip 233 is electrically connected to the first support 210 through an input terminal bonding wire 240. In this way, in the planar optocoupler package structure 200, the light emitted by the light emitting chip 233 is guided to the light receiving chip 231 by the light guiding structure 232, and the light conduction efficiency between the light emitting chip 233 and the light receiving chip 231 is improved, but the first bracket 210 has poor support to the input terminal bonding wire 240, and a problem that the input terminal bonding wire 240 is disconnected easily occurs.

Therefore, there is a great need for a planar optocoupler package structure that can improve the support of the input terminal bonding wires.

Disclosure of Invention

In view of the above, the present application provides a planar optocoupler package structure to solve the above technical problems.

In order to achieve the above-mentioned objective, the present application provides a planar optocoupler package structure, which has a first direction and a second direction perpendicular to each other, the second direction is an up-down spacing direction, and the planar optocoupler package structure includes a first support, a second support, a stack structure and a package layer.

The second support and the first support are arranged at intervals along the first direction, and an input end welding area is arranged on the upper surface of the first support, which is close to the second support. The stack structure comprises a light receiving chip, a light guide structure and a light emitting chip which are sequentially laminated on the upper surface of the second bracket. The light emitting chip is electrically connected with the input end welding area through the input end bonding wire. And the packaging layer wraps the input end welding area and the stack structure. The part of the first bracket provided with the input end welding area protrudes towards the side close to the light emitting chip along the second direction.

In one embodiment, the planar optocoupler package structure includes a MOSFET chip disposed on the second support, and the light receiving chip is electrically connected to the second support through the MOSFET chip; the MOSFET chip and the stack structure are arranged on the second bracket in a partitioning manner; the encapsulation layer encapsulates the MOSFET die.

In one embodiment, the first support extends outwards through the packaging layer to form a first pin; the second support extends outwards through the packaging layer to form a second pin.

In one embodiment, the portion of the first support wrapped in the packaging layer includes a first extension portion and a second extension portion, the distance between the first extension portion and the second support in the first direction decreases in sequence, and the input welding area is located in the second extension portion; the second support wraps the packaging layer and comprises a third extension part, and the stack structure and the MOSFET chip are arranged on the third extension part.

The projection of the first extension part on the first projection surface is at least partially overlapped with the projection of the third extension part on the first projection surface, and the first projection surface is perpendicular to the first direction. The upper surface of the second extension part is closer to the upper surface of the light emitting chip than the upper surface of the first extension part in the second direction.

In one embodiment, the portion of the first support wrapped in the encapsulation layer includes a climbing section, and distances between the first extension, the climbing section, and the second extension and the second support in the first direction decrease in sequence.

The climbing section gradually extends from the first extending part to the second extending part to one side of the first extending part, which is close to the light emitting chip, in the second direction.

In one embodiment, a part of the first support close to the second support is bent and arranged to form a climbing section and a second extension part; alternatively, the portion of the first bracket adjacent to the second bracket is thickened to form a second extension.

In one embodiment, the projection of the second extension portion on the first projection surface at least partially overlaps the projection of the light emitting chip on the first projection surface.

In one embodiment, a first drop distance is provided between the upper surface of the light emitting chip and the upper surface of the first extension part in the second direction; a second drop distance is arranged between the upper surface of the light emitting chip and the upper surface of the second extension part in a second direction; the second drop distance is less than the first drop distance.

In one embodiment, a third drop distance is provided between the upper surface of the second extension portion and the upper surface of the first extension portion in the second direction H, and the third drop distance is 700um to 900um.

In one embodiment, the planar optical coupler package structure includes an insulating pad, and the insulating pad is disposed between the light receiving chip and the second bracket.

The beneficial effects are that: in this application, because the part that the first support was provided with the input bonding pad is protruding towards being close to one side that the luminescence chip was located along the second direction, can make between the upper surface of input bonding pad and luminescence chip have less drop distance in the second direction to can reduce the length of input bonding wire, and then can improve the support nature of first support to input bonding wire, reach the purpose that prevents the disconnection of input bonding wire.

Drawings

Fig. 1 is a schematic diagram of a conventional vertical dual optocoupler package;

FIG. 2 is a schematic diagram of a conventional planar optocoupler package;

FIG. 3 is a schematic structural diagram of an embodiment of a planar optocoupler package of the present application;

FIG. 4 is a schematic dimensional view of FIG. 3;

fig. 5 is a schematic structural diagram of another embodiment of a planar optocoupler package of the present application.

Reference numerals illustrate:

100-an up-down opposite optocoupler packaging structure; 101-a light emitting chip; 102-a light receiving chip; 103-MOSFET chip;

200-plane optocoupler packaging structure; 210-a first rack; 220-a second scaffold; 230-stack structure; 231-a light receiving chip; 232-a light guiding structure; 233-a light emitting chip; 240-input end bonding wires;

300-plane optocoupler package; 310-a first bracket; 311-first pin; 312-a first extension; 313-climbing section; 314-a second extension; 320-a second rack; 321-a second pin; 322-third extension; 330-stack structure; 331-a light receiving chip; 332-a light guiding structure; 333-a light emitting chip; 340-an input terminal bond wire; 350-an output end bonding wire; 360-MOSFET chip; 370-packaging layer;

d1-first drop distance; d2—a second drop distance; d3-third drop distance; l-a first direction; h-a second direction;

400-plane optocoupler package; 410-a first bracket; 420-a second bracket; 430-a stack structure; 431-insulating spacers; 432-a light receiving chip; 433-light guiding structure; 434-a light emitting structure; 440—an input bond wire; 450-output end bonding wires; 460-MOSFET chip; 470-encapsulation layer.

Detailed Description

In order to better understand the technical solutions of the present application, the following describes the present application in further detail with reference to the drawings and the detailed description. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, based on the embodiments herein, which would be apparent to one of ordinary skill in the art without undue burden are within the scope of the present application.

As shown in fig. 2, in the conventional planar optocoupler package structure 200, the support of the input end bonding wire 240 by the first bracket 210 is weak, and the inventors have found through researches that decreasing the drop distance between the upper surface of the portion of the first bracket 210 near the second bracket 220 and the upper surface of the light emitting chip 233 can decrease the length of the input end bonding wire 240, so that the support of the input end bonding wire 240 by the first bracket 210 can be improved, the purpose of preventing the input end bonding wire 240 from being broken is achieved, and accordingly the following embodiments are proposed.

Referring to fig. 3, the planar optocoupler package 300 of the present application has a first direction L and a second direction H perpendicular to each other, the second direction H is an upper-lower spacing direction, and the planar optocoupler package 300 includes a first support 310, a second support 320, a stack structure 330 and a package layer 370.

The second support 320 and the first support 310 are spaced apart from each other along the first direction L, and an input terminal welding area (not shown) is disposed on the upper surface of the first support 310 near the second support 320. The stack structure 330 includes a light receiving chip 331, a light guiding structure 332, and a light emitting chip 333 sequentially stacked on the upper surface of the second holder 320. The light emitting chip 333 is electrically connected to the input terminal bonding pad through the input terminal bonding wire 340. The encapsulation layer 370 encapsulates the input terminal lands and the stack 330. Wherein, the portion of the first support 310 where the input terminal bonding pad is disposed is protruded toward a side near the light emitting chip 333 along the second direction H.

In this way, since the portion of the first support 310 where the input terminal bonding pad is disposed is protruded toward the side close to the light emitting chip 333 along the second direction H, a smaller drop distance between the input terminal bonding pad and the upper surface of the light emitting chip 333 in the second direction can be provided, so that the length of the input terminal bonding wire 340 can be reduced, and the supportability of the first support 310 on the input terminal bonding wire 340 can be improved, thereby achieving the purpose of preventing the input terminal bonding wire 340 from being disconnected.

Alternatively, the light emitted from the light emitting chip 333 includes, but is not limited to, infrared light. The infrared light is, for example, near infrared light or far infrared light, but is not limited thereto. The encapsulation layer 370 is a light blocking encapsulation layer, for example, the encapsulation layer 370 contains carbon black to block light transmitted to the outside of the planar optocoupler package 300. In addition, the encapsulation layer 370 may also include a resin and/or a silicone.

In particular, the first support 310 is configured to receive an input first electrical signal, the light emitting chip 333 emits light in response to the input of the first electrical signal, the light guiding structure 332 guides the light emitted by the light emitting chip 333 to the light receiving chip 331, and the light receiving chip 331 is configured to receive the light conducted by the light guiding structure 332 and convert the light into a corresponding second electrical signal for outputting.

Further, as shown in fig. 3, the planar optocoupler package 300 includes a MOSFET die 360.

The MOSFET chip 360 is disposed on the second holder 320 and electrically connected to the light receiving chip 331 and the second holder 320. The MOSFET chip 360 and the stack structure 330 are disposed on the second support 320 in a partitioned manner. The encapsulation layer 370 encapsulates the MOSFET die 360.

In the above manner, the MOSFET chip 360 is configured to receive the second electrical signal output by the light receiving chip 331 and convert the second electrical signal into the third electrical signal for output by the second bracket 320, so that the MOSFET chip 360 may act as a switch, thereby helping to achieve unidirectional conduction of current. Specifically, the second electrical signal includes, but is not limited to, a voltage signal, and the third electrical signal includes, but is not limited to, a current signal. Optionally, the MOSFET chip 360 is electrically connected to the receiving optical chip 331 through the output terminal bonding wire 350.

Further, as shown in fig. 3, the first support 310 extends outwardly through the encapsulation layer 370 to form the first pins 311. The second support 320 extends outward through the encapsulation layer 370 to form second leads 321. In this way, the first input electrical signal can be received through the first pin 311. The third electric signal output from the MOSFET can be output through the second pin 321.

Optionally, a portion of the second support 320 corresponding to the light receiving chip 331 forms a support base island (not shown) of the light receiving chip 331, and a portion of the second support 320 corresponding to the MOSFET chip 360 forms a support base island of the MOSFET chip 360. The portion of the second holder 320 engaged with the support base of the MOSFET chip 360 is formed with a second lead 321.

Further, as shown in fig. 3, the portion of the first support wrapped in the encapsulation layer 370 includes a first extension portion 312 and a second extension portion 314, where the distance between the first support and the second support 320 in the first direction L decreases in sequence, and the input bonding area is located at the second extension portion 314. The portion of the second carrier 320 that is wrapped within the encapsulation layer 370 includes a third extension 322.

The projection of the first extension 312 on the first projection plane at least partially overlaps the projection of the third extension 322 on the first projection plane, and the first projection plane is a projection plane perpendicular to the first direction L. The upper surface of the second extension 314 is closer to the upper surface of the light emitting chip 333 than the upper surface of the first extension 312 in the second direction H. In this way, the input terminal land can be made closer to the upper surface of the light emitting chip 333 than the first extension 312 in the second direction H.

Optionally, as shown in fig. 3, the portion of the first support wrapped in the encapsulation layer 370 includes a climbing section 313, and distances between the first extension 312, the climbing section 313, and the second extension 314 and the second support 320 in the first direction L sequentially decrease. The climbing section 313 extends from the first extension 312 to the second extension 314 toward a side of the first extension 312 adjacent to the light emitting chip 333 in the second direction H.

Optionally, in an example, a portion of the first bracket 310 proximate to the second bracket 320 is bent to form the climbing section 313 and the second extension 314, but is not limited thereto. In another example, a portion of the first leg 310 proximate to the second leg 320 is thickened to form the second extension 314.

Preferably, the projection of the second extension 314 on the first projection plane at least partially overlaps the projection of the light emitting chip 333 on the first projection plane, and the first projection plane is a projection plane perpendicular to the first direction L, but is not limited thereto.

Alternatively, referring to fig. 4 in conjunction with fig. 3, a first step distance d1 is provided between the upper surface of the light emitting chip 333 and the upper surface of the first extension 312 in the second direction H. The light emitting chip 333 has a second step distance d2 in the second direction H between the upper surface thereof and the upper surface of the second extension 314. The second drop distance d2 is smaller than the first drop distance d1.

Optionally, referring to fig. 4 in conjunction with fig. 3, a third drop distance d3 is provided between the upper surface of the second extension portion 314 and the upper surface of the first extension portion 312 in the second direction H, and the third drop distance d3 is 700um to 900um. In this way, the third drop distance d3 is closer to the height of the stack structure 330, so as to compensate for the drop distance between the upper surface of the light emitting chip 333 and the upper surface of the first extension portion 312, and further make the input terminal bonding wire 350 not easy to break.

In an example, the upper surface of the second extension 314 is a plane or a curved surface, but is not limited thereto. By way of example, and not limitation, the upper surface of the first extension 312 is planar, and the upper surface of the first extension 312 is flush with the upper surface of the light emitting chip 333. In another example, the first, second and third extension portions 312, 314 and 322 each extend straight in the first direction L, but are not limited thereto.

Optionally, referring to fig. 5 in comparison with fig. 3, the planar optocoupler package 400 shown in fig. 5 includes a first support 410, a second support 420, a stack 430, an input terminal bonding wire 440, and a package layer 470. The stack structure 430 includes an insulating spacer 431, a light receiving chip 432, a light guiding structure 433 and a light emitting chip 434 sequentially stacked on the upper surface of the second bracket 420. The first bracket 410, the second bracket 420, the light receiving chip 432, the light guiding structure 433, the light emitting chip 434, the input end bonding wire 440, and the encapsulation layer 470 are the same as the first bracket 310, the second bracket 320, the light receiving chip 331, the light guiding structure 332, the light emitting chip 333, the input end bonding wire 340, and the encapsulation layer 370 shown in fig. 3, and are not described herein. The planar optocoupler package 400 shown in fig. 5 is different from the planar optocoupler package 300 shown in fig. 3 in that the planar optocoupler package further includes an insulating spacer 431, and the insulating spacer 431 is used for insulating the light receiving chip 432 from the second bracket 420.

Alternatively, the planar optocoupler package 400 shown in fig. 5 includes a MOSFET chip 460 and an output bond wire 450, where the MOSFET chip 460 is connected to the receiving optochip 432 through the output bond wire 450. The MOSFET chip 460 and the output bond wire 450 are the same as the MOSFET chip 360 and the output bond wire 350 in the planar optocoupler package 300 shown in fig. 3 and are not described herein.

The foregoing is only the embodiments of the present application, and is not intended to limit the scope of the patent application, and all equivalent structures or equivalent processes using the descriptions and the contents of the present application or other related technical fields are included in the scope of the patent application.

Claims (10)

1. The utility model provides a planar optocoupler packaging structure, its characterized in that, planar optocoupler packaging structure has mutually perpendicular's first direction and second direction, the second direction is upper and lower interval direction, just planar optocoupler packaging structure includes:

a first bracket;

the second support is arranged at intervals along the first direction with the first support, and an input end welding area is arranged on the upper surface of the first support, which is close to the second support;

the stack structure comprises a light receiving chip, a light guide structure and a light emitting chip which are sequentially laminated on the upper surface of the second bracket; the light-emitting chip is electrically connected with the input end welding area through an input end bonding wire;

and the packaging layer wraps the input end welding area and the stack structure;

the part of the first bracket provided with the input end welding area protrudes towards the side close to the light-emitting chip along the second direction.

2. The planar optocoupler package of claim 1, wherein the planar optocoupler package comprises:

the MOSFET chip is arranged on the second bracket, and the light receiving chip is electrically connected with the second bracket through the MOSFET chip; the MOSFET chip and the stack structure are arranged on the second bracket in a partitioning manner; the encapsulation layer encapsulates the MOSFET die.

3. The planar optocoupler package of claim 1 wherein the first support extends outwardly through the package layer to form a first pin; the second support extends outwards through the packaging layer to form a second pin.

4. The planar optocoupler package of claim 2 wherein the portion of the first support wrapped within the package layer comprises a first extension and a second extension that decrease in sequence in distance from the second support in the first direction, the input bond pad being located at the second extension; the second support is wrapped in the packaging layer and comprises a third extension part, and the stack structure and the MOSFET chip are arranged on the third extension part;

the projection of the first extension part on a first projection surface is at least partially overlapped with the projection of the third extension part on the first projection surface, and the first projection surface is a projection surface perpendicular to the first direction; the upper surface of the second extension portion is closer to the upper surface of the light emitting chip than the upper surface of the first extension portion in the second direction.

5. The planar optocoupler of claim 4 wherein the portion of the first support wrapped within the encapsulation layer comprises a climbing section, the first extension, the climbing section, and the second extension being successively less distant from the second support in the first direction;

the climbing section gradually extends from the first extending portion to the second extending portion to one side of the first extending portion, which is close to the light emitting chip, in the second direction.

6. The planar optocoupler of claim 5 wherein a portion of the first support adjacent the second support is folded to form the climbing section and the second extension; alternatively, a portion of the first bracket adjacent to the second bracket is thickened to form the second extension.

7. The planar optocoupler package of claim 4, wherein the projection of the second extension onto the first projection plane at least partially overlaps the projection of the light emitting chip onto the first projection plane.

8. The planar optocoupler package of claim 4 wherein a first step distance is provided between the upper surface of the light emitting chip and the upper surface of the first extension in the second direction; a second drop distance is arranged between the upper surface of the light emitting chip and the upper surface of the second extension part in the second direction; the second drop distance is less than the first drop distance.

9. The planar optocoupler of claim 4 wherein a third step distance is provided between the upper surface of the second extension and the upper surface of the first extension in the second direction H, and the third step distance is 700um to 900um.

10. The planar optocoupler package of claim 4, wherein the planar optocoupler package comprises an insulating spacer disposed between the light receiving chip and the second support.