Diode integrated structure for an optical coupling device

Abstract

The application relates to a diode integrated structure for an optical coupling device, wherein a light input light emitting diode and a light detection diode are arranged on the front surface of a substrate; the light emitting diode comprises a buffer layer, a first semiconductor layer, an active layer, a second semiconductor layer, a transparent conductive layer, a first contact electrode, a first extension electrode, an insulating protective layer, a first pad and a second pad; and the light detection diode comprises a buffer layer, a first semiconductor layer, an active layer, a second semiconductor layer, a transparent conductive layer, a first contact electrode, a first extension electrode, an insulating protective layer, a first pad and a second pad. The application provides a simple diode structure device which can be directly used for optical coupling, can reduce the device capacitance, improve the response frequency of the optical coupling device, can enhance the coupling efficiency of the optical coupling device, and the coupling efficiency is adjustable.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of semiconductor, and particularly relates to a diode integrated structure for an optical coupling device. BACKGROUND

[0002] An optical coupling device is a device for transmitting electrical signals by using light as a medium, and is widely used in solid-state switches, trigger circuits and pulse amplification circuits. The response frequency of the optical coupling device is limited by the switching speed of the light source, the coupling distance and the response speed of the optical detector, and is usually in the order of tens of KHz. Among them, reducing the capacitance of the light-emitting diode as the light source can further improve the response speed. SUMMARY

[0003] The present application aims to overcome the deficiencies in the prior art, and provides a diode integrated structure for an optical coupling device.

[0004] According to the technical scheme provided by the present application, the diode integrated structure for an optical coupling device is provided with a light input light-emitting diode and a light detection diode on the front surface of a substrate.

[0005] The light input light-emitting diode comprises: a light input light-emitting epitaxial stack, which comprises a light input buffer layer, a light input first semiconductor layer, a light input active layer and a light input second semiconductor layer stacked in sequence on the front surface of the substrate; a light input transparent conductive layer, which covers part of the light input second semiconductor layer; a light input first electrode, which comprises a light input first contact electrode and a light input first expansion electrode, and is connected with the light input first semiconductor layer; a light input second electrode, which comprises a light input second contact electrode and a light input second expansion electrode, and is connected with the light input transparent conductive layer; a light input insulating protective layer, which covers the sidewall of the light input light-emitting epitaxial stack and the front surface of the light input transparent conductive layer, and has a first through hole and a second through hole; a light input first pad which is electrically connected with the light input first contact electrode through the first through hole, and a light input second pad which is electrically connected with the light input second contact electrode through the second through hole.

[0006] The light detection diode comprises: a light detection epitaxial stack, the light detection epitaxial stack comprising, in sequence from the front surface of the substrate, a light detection buffer layer, a light detection first semiconductor layer, a light detection active layer, and a light detection second semiconductor layer; a light detection transparent conductive layer covering part of the light detection second semiconductor layer; a light detection first electrode comprising a light detection first contact electrode and a light detection first extension electrode connected to the light detection first semiconductor layer; a light detection second electrode comprising a light detection second contact electrode and a light detection second extension electrode connected to the light detection transparent conductive layer; a light detection insulating protective layer covering the sidewalls of the light detection epitaxial stack and the front surface of the light detection transparent conductive layer, the light detection insulating protective layer having a third through hole and a fourth through hole; a light detection first pad electrically connected to the light detection first contact electrode through the third through hole, and a light detection second pad electrically connected to the light detection second contact electrode through the fourth through hole.

[0007] The light input buffer layer and the light detection buffer layer are arranged in a spaced manner on the front surface of the substrate.

[0008] Preferably, in the vertical direction, the light input first contact electrode and the light input first extension electrode both avoid the light input second pad, and the light input second contact electrode and the light input second extension electrode both avoid the light input first pad.

[0009] In the vertical direction, the light detection first contact electrode and the light detection first extension electrode both avoid the light detection second pad, and the light detection second contact electrode and the light detection second extension electrode both avoid the light detection first pad.

[0010] Preferably, the light input light emitting epitaxial stack on the side of the light detection diode has an overall outward convex shape, and the light detection epitaxial stack on the side of the light input light emitting diode has an overall inward concave shape.

[0011] Preferably, the side surface cross section of the light input light emitting epitaxial stack on the side of the light detection diode is an outward convex circular arc shape.

[0012] Preferably, the width of the light input first pad and the width of the light input second pad are both 1 / 3 to 2 / 3 of the width of the light input transparent conductive layer, and the light input first pad and the light input second pad are both away from the light detection diode.

[0013] The width of the light detection first pad and the width of the light detection second pad are both 1 / 3 to 2 / 3 of the width of the light detection transparent conductive layer, and the light detection first pad and the light detection second pad are both away from the light input light emitting diode.

[0014] Preferably, a convex lens is arranged between the light input light emitting diode and the light detection diode.

[0015] As preferred, convex lens is arranged near the light input LED, and concave lens is arranged near the light detecting diode.

[0016] As preferred, light input strip-shaped protrusions are arranged on the side of the light input LED epitaxial layer facing the light detecting diode;

[0017] Light detecting strip-shaped recesses are arranged on the side of the light detecting epitaxial layer facing the light input LED.

[0018] As preferred, light input strip-shaped protrusions are densely distributed in the central area of the convex lens, and sparsely distributed in the two ends of the convex lens, and the light detecting strip-shaped recesses are uniformly distributed.

[0019] As preferred, the light input strip-shaped protrusions are semi-cylindrical, semi-elliptical cylindrical, multi-prism, multi-prism, semi-conical or semi-circular truncated cone;

[0020] The light detecting strip-shaped recesses are semi-cylindrical, semi-elliptical cylindrical, multi-prism, multi-prism, semi-conical or semi-circular truncated cone.

[0021] As preferred, insulating protective layer strip-shaped protrusions are arranged on the side of the light input insulating protective layer facing the light detecting diode, and insulating protective layer strip-shaped recesses are arranged on the side of the light detecting insulating protective layer facing the light input LED.

[0022] As preferred, a distributed Bragg reflector is arranged on the back of the substrate.

[0023] As preferred, the light input first pad is convex or concave, the light input second pad is concave or convex, and the light input first pad and the light input second pad are concave-convex matched;

[0024] The light detecting first pad is convex or concave, the light detecting second pad is concave or convex, and the light detecting first pad and the light detecting second pad are concave-convex matched.

[0025] As preferred, the number of light input LEDs is one or more, and the number of light detecting diodes is one.

[0026] A diode integrated structure for optical coupling device, light input LED and light detecting diode are arranged on the front of the substrate;

[0027] The light input light emitting diode comprises: a light input light emitting epitaxial stack comprising a light input buffer layer, a light input first semiconductor layer, a light input active layer, a light input second semiconductor layer stacked in sequence on the front surface of a substrate; a light input transparent conductive layer covering part of the light input second semiconductor layer; a light input insulating protective layer covering the sidewall of the light input light emitting epitaxial stack and the front surface of the light input transparent conductive layer, the light input insulating protective layer having one or more first through holes and second through holes; a light input first pad electrically connected to the light input first semiconductor layer through the first through hole, and a light input second pad electrically connected to the light input transparent conductive layer through the second through hole.

[0028] The light detection diode comprises: a light detection epitaxial stack comprising a light detection buffer layer, a light detection first semiconductor layer, a light detection active layer, a light detection second semiconductor layer stacked in sequence on the front surface of a substrate; a light detection transparent conductive layer covering part of the light detection second semiconductor layer; a light detection insulating protective layer covering the sidewall of the light detection epitaxial stack and the front surface of the light detection transparent conductive layer, the light detection insulating protective layer having one or more third through holes and fourth through holes; a light detection first pad electrically connected to the light detection first semiconductor layer through the third through hole, and a light detection second pad electrically connected to the light detection transparent conductive layer through the fourth through hole.

[0029] The light input buffer layer and the light detection buffer layer are arranged in a spaced manner on the front surface of the substrate.

[0030] Preferably, a distributed Bragg reflector is arranged on the back surface of the substrate.

[0031] The application can improve the response frequency of the optical coupling device, enhance the coupling efficiency of the optical coupling device, and adjust the coupling efficiency, and has high breakdown voltage. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a top view of embodiment 1 of the application.

[0033] Figure 2 is Figure 1 A-A sectional view of

[0034] Figure 3 is a top view of embodiment 2 of the application.

[0035] Figure 4 is Figure 3 B-B sectional view of

[0036] Figure 5 is a top view of embodiment 3 of the application.

[0037] Figure 6 is a top view of embodiment 4 of the application.

[0038] Figure 7 is a top view of the embodiment 5 of the present application.

[0039] Figure 8 is a C-C sectional view of Figure 7

[0040] Figure 9 is a top view of the embodiment 6 of the present application.

[0041] Figure 10 is a D-D sectional view of Figure 9

[0042] Figure 11 is an E-E sectional view of Figure 9

[0043] Figure 12 is a top view of the embodiment 7 of the present application.

[0044] Figure 13 is a top view of the embodiment 8 of the present application.

[0045] Figure 14 is a top view of the embodiment 9 of the present application.

[0046] Figure 15 is a F-F sectional view of Figure 14

[0047] Figure 16 is a top view of the embodiment 10 of the present application.

[0048] Figure 17 is a G-G sectional view of Figure 16

[0049] Figure 18 is a top view of the embodiment 11 of the present application.

[0050] Figure 19 is a H-H sectional view of Figure 18 DETAILED DESCRIPTION

[0051] The present application will be further described below in conjunction with specific embodiments.

[0052] The present application can be n-p structure or p-n structure.

[0053] ​​​​​​The following embodiments are described for n-p structure, wherein the light input first contact electrode 3.6 and the light detection first contact electrode 4.6 are both N contact electrodes, the light input second contact electrode 3.7 and the light detection second contact electrode 4.7 are both P contact electrodes, the light input second semiconductor layer 3.4 and the light detection second semiconductor layer 4.4 are both p-GaN, the light input first semiconductor layer 3.2 and the light detection first semiconductor layer 4.2 are both n-GaN, and the light input buffer layer 3.1 and the light detection buffer layer 4.1 are both u-GaN.

[0054] In the following embodiments, the light input insulating protective layer 3.8 and the light detection insulating protective layer 4.8 can be connected or not connected.

[0055] Embodiment 1

[0056] As shown in Figure 1 , Figure 2 , a diode integrated structure for an optical coupling device is provided, wherein a light input light emitting diode 3 and a light detection diode 4 are arranged on the front surface of a substrate 2.

[0057] The light input light emitting diode 3 comprises: a light input light emitting epitaxial stack, which comprises a light input buffer layer 3.1, a light input first semiconductor layer 3.2, a light input active layer 3.3, and a light input second semiconductor layer 3.4 stacked in sequence on the front surface of the substrate 2; a light input transparent conductive layer 3.5 covering part of the light input second semiconductor layer 3.4; a light input first electrode comprising a light input first contact electrode 3.61 and a light input first extension electrode 3.62 connected to the light input first semiconductor layer 3.2; a light input second electrode comprising a light input second contact electrode 3.71 and a light input second extension electrode 3.72 connected to the light input transparent conductive layer 3.5; a light input insulating protective layer 3.8 covering the sidewalls of the light input light emitting epitaxial stack and the front surface of the light input transparent conductive layer 3.5, the light input insulating protective layer 3.8 having a first through hole and a second through hole; a light input first pad 3.9 electrically connected to the light input first electrode through the first through hole, and a light input second pad 3.10 electrically connected to the light input second electrode through the second through hole; and the light input first pad 3.9 and the light input second pad 3.10 are both rectangular.

[0058] The light detection diode 4 comprises: a light detection epitaxial stack comprising a light detection buffer layer 4.1, a light detection first semiconductor layer 4.2, a light detection active layer 4.3, a light detection second semiconductor layer 4.4, which are sequentially stacked on the front surface of the substrate 2; a light detection transparent conductive layer 4.5 covering part of the light detection second semiconductor layer 4.4; a light detection first electrode comprising a light detection first contact electrode 4.61 and a light detection first extension electrode 4.62 connected with the light detection first semiconductor layer 4.2; a light detection second electrode comprising a light detection second contact electrode 4.71 and a light detection second extension electrode 4.72 connected with the light detection transparent conductive layer 4.5; a light detection insulating protective layer 4.8 covering the sidewalls of the light detection epitaxial stack and the front surface of the light detection transparent conductive layer 4.5, the light detection insulating protective layer 4.8 having a third through hole and a fourth through hole; a light detection first pad 4.9 electrically connected with the light detection first electrode through the third through hole, and a light detection second pad 4.10 electrically connected with the light detection second electrode through the fourth through hole; and the light detection first pad 4.9 and the light detection second pad 4.10 are both rectangular.

[0059] The light input buffer layer 3.1 and the light detection buffer layer 4.1 are arranged in a spaced manner on the front surface of the substrate 2.

[0060] In the vertical direction, the light input first contact electrode 3.61 avoids the light input second pad 3.10, the light input first extension electrode 3.62 does not avoid the light input second pad 3.10, the light input second contact electrode 3.71 avoids the light input first pad 3.9, and the light input second extension electrode 3.72 does not avoid the light input first pad 3.9.

[0061] In the vertical direction, the light detection first contact electrode 4.61 avoids the light detection second pad 4.10, the light detection first extension electrode 4.62 does not avoid the light detection second pad 4.10, the light detection second contact electrode 4.71 avoids the light detection first pad 4.9, and the light detection second extension electrode 4.72 does not avoid the light detection first pad 4.9.

[0062] This embodiment integrates the light input light-emitting diode 3 and the light detection diode 4 together through the substrate 2, utilizes the light emitted by the light input light-emitting diode 3 and the light input of the epitaxial stack in the light detection diode 4 to realize high-efficiency coupling, and realizes effective adjustment of the light coupling efficiency and significant improvement and adjustment of the breakdown voltage of the integrated device through adjustment of the distance between the light input light-emitting diode 3 and the light detection diode 4. In addition, the high-response-speed characteristics of the light input light-emitting diode 3 and the light detection diode 4 can realize fast response of the light coupling integrated device and improve the response frequency of the device.

[0063] Embodiment 2

[0064] As Figure 3 , Figure 4 shown, this embodiment is based on embodiment 1, and further comprises: a convex lens 5 is arranged between the light input LED 3 and the light detection diode 4, and the convex lens 5 is arranged on the front surface of the substrate 2. A distributed Bragg reflector 1 is arranged on the back surface of the substrate 2.

[0065] The arrangement of the convex lens 5 can more effectively focus the light emitted by the light input LED 3 on the light detection diode 4, thereby significantly improving the light coupling efficiency.

[0066] Embodiment 3

[0067] As Figure 5 shown, this embodiment is based on embodiment 1, and further comprises: a convex lens 5 and a concave lens 6 are arranged between the light input LED 3 and the light detection diode 4, the light input insulating protective layer 3.8 and the light detection insulating protective layer 4.8 are connected, the convex lens 5 is arranged on the front surface of the light input insulating protective layer 3.8, the concave lens 6 is arranged on the front surface of the light detection insulating protective layer 4.8, the convex lens 5 is close to the light input LED 3, and the concave lens 6 is close to the light detection diode 4.

[0068] The convex lens 5 can effectively collect the light emitted by the light input LED 3, reduce the scattering loss of the light, and the concave lens 6 close to the light detection diode 4 can scatter the light to a certain extent, increase the light contact area, and further improve the light coupling efficiency.

[0069] Embodiment 4

[0070] As Figure 6 shown, a diode integrated structure for a light coupling device, the light input LED 3 and the light detection diode 4 are arranged on the front surface of the substrate 2;

[0071] The light input LED 3 comprises: a light input epitaxial stack comprising, in sequence, a light input buffer layer 3.1, a light input first semiconductor layer 3.2, a light input active layer 3.3, a light input second semiconductor layer 3.4, on the front surface of the substrate 2; a light input transparent conductive layer 3.5 covering part of the light input second semiconductor layer 3.4; a light input first electrode comprising a light input first contact electrode 3.61 and a light input first extension electrode 3.62, connected to the light input first semiconductor layer 3.2; a light input second electrode comprising a light input second contact electrode 3.71 and a light input second extension electrode 3.72, connected to the light input transparent conductive layer 3.5; a light input insulating protective layer 3.8 covering the sidewalls of the light input epitaxial stack and the front surface of the light input transparent conductive layer 3.5, the light input insulating protective layer 3.8 having a first through hole and a second through hole; a light input first pad 3.9 electrically connected to the light input first electrode through the first through hole, and a light input second pad 3.10 electrically connected to the light input second electrode through the second through hole.

[0072] The light input LED 3 comprises: a light input epitaxial stack comprising, in sequence, a light input buffer layer 3.1, a light input first semiconductor layer 3.2, a light input active layer 3.3, a light input second semiconductor layer 3.4, on the front surface of the substrate 2; a light input transparent conductive layer 3.5 covering part of the light input second semiconductor layer 3.4; a light input first electrode comprising a light input first contact electrode 3.61 and a light input first extension electrode 3.62, connected to the light input first semiconductor layer 3.2; a light input second electrode comprising a light input second contact electrode 3.71 and a light input second extension electrode 3.72, connected to the light input transparent conductive layer 3.5; a light input insulating protective layer 3.8 covering the sidewalls of the light input epitaxial stack and the front surface of the light input transparent conductive layer 3.5, the light input insulating protective layer 3.8 having a first through hole and a second through hole; a light input first pad 3.9 electrically connected to the light input first electrode through the first through hole, and a light input second pad 3.10 electrically connected to the light input second electrode through the second through hole.

[0073] The light input buffer layer 3.1 and the light detection buffer layer 4.1 are arranged in a spaced manner on the front surface of the substrate 2.

[0074] In the vertical direction, the light input first contact electrode 3.61 and the light input first extension electrode 3.62 both avoid the light input second pad 3.10, and the light input second contact electrode 3.71 and the light input second extension electrode 3.72 both avoid the light input first pad 3.9.

[0075] In the vertical direction, the light detecting first contact electrode 4.61 and the light detecting first extension electrode 4.62 both avoid the light detecting second pad 4.10, and the light detecting second contact electrode 4.71 and the light detecting second extension electrode 4.72 both avoid the light detecting first pad 4.9.

[0076] A convex lens 5 is arranged close to the light input LED 3, and a concave lens 6 is arranged close to the light detecting diode 4.

[0077] A light input strip-shaped protrusion 3.11 is arranged on the side of the light input LED epitaxial layer facing the light detecting diode 4, and a light detecting strip-shaped recess 4.11 is arranged on the side of the light detecting epitaxial layer facing the light input LED 3.

[0078] The light input strip-shaped protrusions 3.11 corresponding to the central area of the convex lens 6 are densely distributed, the light input strip-shaped protrusions 3.11 corresponding to the two ends of the convex lens 6 are sparsely distributed, and the light detecting strip-shaped recesses 4.11 are uniformly distributed.

[0079] The light input first pad 3.9 is in the shape of a convex character, the light input second pad 3.10 is in the shape of a concave character, the light detecting first pad 4.9 is in the shape of a convex character, and the light detecting second pad 4.10 is in the shape of a concave character.

[0080] Compared with Embodiment 3, the light input strip-shaped protrusions 3.11 densely distributed near the center can effectively improve the light extraction efficiency of the middle section, making the light emission more concentrated, and the light detecting strip-shaped recesses 4.11 can effectively reduce the reflection of the side light, so that more light passes through the side of the light detecting diode 4, enhancing the coupling with the light detecting active layer.

[0081] Embodiment 5

[0082] As shown in Figure 7 , Figure 8 this embodiment adds, on the side of the light input LED epitaxial layer facing the light detecting diode 4, the light input strip-shaped protrusions 3.11;

[0083] on the side of the light detecting epitaxial layer facing the light input LED 3, the light detecting strip-shaped recesses 4.11;

[0084] a distributed Bragg reflector 1 is arranged on the back of the substrate 2.

[0085] The light input strip-shaped protrusions 3.11 on the side of the light input LED 3 and the light detecting strip-shaped recesses 4.11 on the side of the light detecting diode 4 have the same effects and advantages as in Embodiment 4.

[0086] Embodiment 6

[0087] As Figure 9 , Figure 10 and Figure 11 shown, the difference between this embodiment and embodiment 1 is that:

[0088] In the vertical direction, the light input first contact electrode 3.61 and the light input first extension electrode 3.62 both avoid the light input second pad 3.10, and the light input second contact electrode 3.71 and the light input second extension electrode 3.72 both avoid the light input first pad 3.9;

[0089] In the vertical direction, the light detection first contact electrode 4.61 and the light detection first extension electrode 4.62 both avoid the light detection second pad 4.10, and the light detection second contact electrode 4.71 and the light detection second extension electrode 4.72 both avoid the light detection first pad 4.9.

[0090] The light input first pad 3.9 is convex, the light input second pad 3.10 is concave, the light detection first pad 4.9 is convex, and the light detection second pad 4.10 is concave.

[0091] A distributed Bragg reflector 1 is arranged on the back surface of the substrate 2.

[0092] Compared with embodiment 1, this structure can reduce the additional capacitance introduced by the metal-insulator-metal (MIM) structure in space, reduce the RC signal delay, and improve the response frequency of the optical coupling device.

[0093] Embodiment 7

[0094] As Figure 12 shown, the difference between this embodiment and embodiment 6 is that:

[0095] The width of the light input first pad 3.9 and the light input second pad 3.10 is 1 / 3-2 / 3 of the width of the light input transparent conductive layer 3.5, and the light input first pad 3.9 and the light input second pad 3.10 are away from the light detection diode 4.

[0096] The width of the light detection first pad 4.9 and the light detection second pad 4.10 is 1 / 3-2 / 3 of the width of the light detection transparent conductive layer 4.5, and the light detection first pad 4.9 and the light detection second pad 4.10 are away from the light input light-emitting diode 3.

[0097] Compared with embodiment 6, this structure can increase the light-emitting area of the light input light-emitting diode 3, enhance the light-emitting intensity, and thus improve the optical coupling efficiency. At the same time, the coupling distance between the light input light-emitting diode 3 and the light detection diode 4 can be adjusted, and an optical coupling device with adjustable optical coupling efficiency can be realized.

[0098] Embodiment 8

[0099] As shown in Figure 13 the difference between this embodiment and embodiment 1 is that two light input light emitting diodes 3 are arranged on the front surface of the patterned sapphire substrate 2.

[0100] Compared with embodiment 1, this structure can better adjust the light emitting uniformity of the light input light emitting diode 3, thereby effectively adjusting the light coupling efficiency.

[0101] Embodiment 9

[0102] As shown in Figure 14 and Figure 15 the difference between this embodiment and embodiment 6 is that:

[0103] The light input light emitting epitaxial layer on the side of the light detecting diode 4 is in an overall convex shape, and the light detecting epitaxial layer on the side of the light input light emitting diode 3 is in an overall concave shape;

[0104] and the side surface cross section of the light input light emitting epitaxial layer on the side of the light detecting diode 4 is in a convex circular arc shape.

[0105] This structure can also effectively improve the light taking efficiency of the light input light emitting diode 3 and the light input on one end of the light detecting diode 4, thereby improving the light coupling efficiency.

[0106] Embodiment 10

[0107] As shown in Figure 16 and Figure 17 a diode integrated structure for a light coupling device, a light input light emitting diode 3 and a light detecting diode 4 are arranged on the front surface of a substrate 2;

[0108] The light input light emitting diode 3 comprises: a light input light emitting epitaxial layer, the light input light emitting epitaxial layer comprises, in sequence from top to bottom, a light input buffer layer 3.1, a light input first semiconductor layer 3.2, a light input active layer 3.3, a light input second semiconductor layer 3.4, a light input transparent conductive layer 3.5 covering part of the light input second semiconductor layer 3.4, and a light input insulating protective layer 3.8 covering the sidewall of the light input light emitting epitaxial layer and the front surface of the light input transparent conductive layer 3.5, the light input insulating protective layer 3.8 having a first through hole and a second through hole; a light input first pad 3.9 is electrically connected to the light input first semiconductor layer 3.2 through the first through hole, and a light input second pad 3.10 is electrically connected to the light input transparent conductive layer 3.5 through the second through hole;

[0109] The photodetector diode 4 includes: a photodetector epitaxial stack, comprising a photodetector buffer layer 4.1, a photodetector first semiconductor layer 4.2, a photodetector active layer 4.3, and a photodetector second semiconductor layer 4.4 stacked sequentially on the front side of the substrate 2; a photodetector transparent conductive layer 4.5 covering part of the photodetector second semiconductor layer 4.4; and a photodetector insulating protective layer 4.8 covering the sidewalls of the photodetector epitaxial stack and the front side of the photodetector transparent conductive layer 4.5, the photodetector insulating protective layer 4.8 having a third via and a fourth via; a photodetector first pad 4.9 electrically connected to the photodetector first semiconductor layer through the third via, and a photodetector second pad 4.10 electrically connected to the photodetector transparent conductive layer through the fourth via.

[0110] The light input buffer layer 3.1 and the light detection buffer layer 4.1 are disposed at intervals on the front side of the substrate 2.

[0111] A distributed Bragg reflector 1 is provided on the back side of the substrate 2.

[0112] Compared to Example 6, this structure further reduces the stacking of metal-insulator-metal structures, which can further reduce RC signal delay and improve the response frequency of the optocoupler.

[0113] Example 11

[0114] like Figure 18 and Figure 19 As shown, the difference between this embodiment and embodiment 10 is that the light input insulating protective layer 3.8 has multiple first through holes and multiple second through holes; the light input first pad 3.9 is electrically connected to the light input first semiconductor layer 3.2 through multiple first through holes, and the light input second pad 3.10 is electrically connected to the light input transparent conductive layer 3.5 through multiple second through holes;

[0115] The photodetector insulating protective layer 4.8 has multiple third through holes and multiple fourth through holes; the photodetector first pad 4.9 is electrically connected to the photodetector first semiconductor layer 4.2 through multiple third through holes, and the photodetector second pad 4.10 is electrically connected to the photodetector transparent conductive layer 4.5 through multiple fourth through holes.

[0116] Compared to Example 10, this structure improves the light emission uniformity of the light-input LED 3, reduces the current congestion effect, and increases the light emission intensity of the light-input LED 3 through porous carrier injection, thereby improving the optical coupling efficiency.

[0117] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A diode integrated structure for an optical coupling device, characterized by: The light input light emitting diode (3) is arranged on the front surface of the substrate (2); The light input light emitting diode (3) comprises: a light input light emitting epitaxial stack, the light input light emitting epitaxial stack comprising, in sequence, a light input buffer layer (3.1), a light input first semiconductor layer (3.2), a light input active layer (3.3), and a light input second semiconductor layer (3.4) stacked on the front surface of the substrate (2); a light input transparent conductive layer (3.5) covering part of the light input second semiconductor layer (3.4); a light input first electrode comprising a light input first contact electrode (3.61) and a light input first extension electrode (3.62) connected with the light input first semiconductor layer (3.2); a light input second electrode comprising a light input second contact electrode (3.71) and a light input second extension electrode (3.72) connected with the light input transparent conductive layer (3.5); and a light input insulating protective layer (3.8) covering the sidewalls of the light input light emitting epitaxial stack and the front surface of the light input transparent conductive layer (3.5), the light input insulating protective layer (3.8) having a first through hole and a second through hole; a light input first pad (3.9) electrically connected with the light input first electrode through the first through hole, and a light input second pad (3.10) electrically connected with the light input second electrode through the second through hole; The light detection diode (4) comprises: a light detection epitaxial stack, the light detection epitaxial stack comprising, in sequence, a light detection buffer layer (4.1), a light detection first semiconductor layer (4.2), a light detection active layer (4.3), and a light detection second semiconductor layer (4.4) stacked on the front surface of the substrate (2); a light detection transparent conductive layer (4.5) covering part of the light detection second semiconductor layer (4.4); a light detection first electrode comprising a light detection first contact electrode (4.61) and a light detection first extension electrode (4.62) connected with the light detection first semiconductor layer (4.2); a light detection second electrode comprising a light detection second contact electrode (4.71) and a light detection second extension electrode (4.72) connected with the light detection transparent conductive layer (4.5); and a light detection insulating protective layer (4.8) covering the sidewalls of the light detection epitaxial stack and the front surface of the light detection transparent conductive layer (4.5), the light detection insulating protective layer (4.8) having a third through hole and a fourth through hole; a light detection first pad (4.9) electrically connected with the light detection first electrode through the third through hole, and a light detection second pad (4.10) electrically connected with the light detection second electrode through the fourth through hole; The light input buffer layer (3.1) and the light detection buffer layer (4.1) are arranged on the front surface of the substrate (2) in a spaced manner; In the vertical direction, the light input first contact electrode (3.61) and the light input first extension electrode (3.62) both avoid the light input second pad (3.10), and the light input second contact electrode (3.71) and the light input second extension electrode (3.72) both avoid the light input first pad (3.9); In the vertical direction, the light detection first contact electrode (4.61) and the light detection first extension electrode (4.62) both avoid the light detection second pad (4.10), and the light detection second contact electrode (4.71) and the light detection second extension electrode (4.72) both avoid the light detection first pad (4.9); The light input light emitting epitaxial layer on the side of the light input light emitting diode (3) is in an overall concave shape; The side surface of the light input light emitting epitaxial layer on the side of the light input light emitting diode (3) is in an overall concave shape.

2. The diode integrated structure for an optical coupling device according to claim 1, characterized in that: The side surface of the light input light emitting epitaxial layer on the side of the light input light emitting diode (3) is in an overall concave shape. The width of the light input first pad (3.9) and the light input second pad (3.10) is 1 / 3-2 / 3 of the width of the light input transparent conductive layer (3.5), and the light input first pad (3.9) and the light input second pad (3.10) are both away from the light detection diode (4); 3. The diode integrated structure for an optical coupling device according to claim 2, characterized in that the first and second electrodes are formed by a plurality of electrodes. The width of the light detection first pad (4.9) and the light detection second pad (4.10) is 1 / 3-2 / 3 of the width of the light detection transparent conductive layer (4.5), and the light detection first pad (4.9) and the light detection second pad (4.10) are both away from the light input light emitting diode (3). The light input light emitting diode (3) and the light detection diode (4) are provided with a convex lens (5) and a concave lens (6), the convex lens (5) is close to the light input light emitting diode (3), and the concave lens (6) is close to the light detection diode (4); The light input strip-shaped protrusion (3.11) is provided on the side surface of the light input light emitting epitaxial layer on the side of the light input light emitting diode (3); 4. The diode integrated structure for an optical coupling device according to claim 3, characterized by: The light detection strip-shaped recess (4.11) is provided on the side surface of the light detection epitaxial layer on the side of the light input light emitting diode (3).

5. A diode integrated structure for an optical coupling device according to claim 3 or 4, characterized in that: The light input strip-shaped protrusion (3.11) is in a semicircular cylindrical shape, a semi-elliptical cylindrical shape, a multi-prism shape, a multi-prismatic shape, a semicircular conical shape, or a semicircular truncated shape; The light detection strip-shaped recess (4.11) is in a semicircular cylindrical shape, a semi-elliptical cylindrical shape, a multi-prism shape, a multi-prismatic shape, a semicircular conical shape, or a semicircular truncated shape.

6. A diode integrated structure for an optical coupling device as claimed in claim 3 or 4, characterized in that the diode is a PIN diode. The light input insulating protective layer (3.8) on the side of the light input light emitting diode (3) is provided with an insulating protective layer strip-shaped protrusion (3.81), and the light detection insulating protective layer (4.8) on the side of the light input light emitting diode (3) is provided with an insulating protective layer strip-shaped recess (4.81).

7. The diode integrated structure for an optical coupling device according to claim 6, characterized in that: A distributed Bragg reflector (1) is provided on the back surface of the substrate (2).

8. The diode integrated structure for an optical coupling device according to claim 6, characterized by: The light input first pad (3.9) is in a convex shape or a concave shape, the light input second pad (3.10) is in a concave shape or a convex shape, and the light input first pad (3.9) and the light input second pad (3.10) are in a concave-convex cooperation. The light detection first pad (4.9) is in a convex shape or a concave shape, and the light detection second pad (4.10) is in a concave shape or a convex shape, and the light detection first pad (4.9) and the light detection second pad (4.10) are in a concave-convex matching mode.

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