CN212303694U

CN212303694U - Flip LED chip

Info

Publication number: CN212303694U
Application number: CN202021803721.3U
Authority: CN
Inventors: 不公告发明人
Original assignee: Focus Lightings Technology Suqian Co ltd
Current assignee: Focus Lightings Technology Suqian Co ltd
Priority date: 2020-08-25
Filing date: 2020-08-25
Publication date: 2021-01-05
Anticipated expiration: 2030-08-25

Abstract

The utility model provides a flip LED chip, the flip LED chip includes the substrate and locates semiconductor layer, transparent conducting layer and insulating protective layer on it in proper order, semiconductor layer, transparent conducting layer and insulating protective layer are formed with first through-hole, second through-hole and third through-hole that link up its upper and lower surfaces respectively, the axis of first through-hole, second through-hole and third through-hole coincides, exposes the partial upper surface of the substrate; the side wall surfaces of the first through hole, the second through hole and the third through hole and the exposed upper surface of the substrate are surrounded to form a thimble extending area. The first through hole, the second through hole and the third through hole are respectively arranged to form the thimble stretching area, so that the thimble can enter the front inside of the LED chip along the thimble stretching area when the LED chip is jacked up, and can be abutted against the high-hardness substrate without piercing on a thin and brittle insulating protective layer or a conductive layer, and the insulating protective layer is prevented from being punctured by the sharp thimble to cause the layer to fall off.

Description

Flip LED chip

Technical Field

The utility model relates to a semiconductor luminescent device field specifically relates to a flip-chip LED chip.

Background

As a novel energy-saving and environment-friendly solid-state illumination Light source, a Light Emitting Diode (LED) has the advantages of high energy efficiency, small size, Light weight, fast response speed, long service life and the like, so that the Light Emitting Diode (LED) is widely applied in many fields. The flip LED chip is widely applied due to good heat dissipation, wire bonding saving and good reliability.

In the current manufacturing process of the flip LED packaging chip, the chip needs to be transferred from a blue film to a substrate through a die bonder, an ejector pin is arranged below a machine table of the die bonder, and a suction nozzle is arranged above the machine table. In the transferring process, the LED chip to be packaged is placed on the machine table, the inverted LED chip is jacked upwards through the ejector pin, then the suction nozzle moves downwards to adsorb the chip and transfer the chip to the substrate, and then the chip on the substrate is packaged.

However, the front surface of the flip LED chip is usually provided with an insulating protective layer for insulation, the insulating protective layer is usually silicon dioxide, and the insulating protective layer is thin and brittle, and is easily punctured by a sharp thimble to cause the layer to fall off, so that the conductive layer inside the LED chip is exposed, the structural integrity of the LED chip is damaged, and the short circuit condition between the positive electrode and the negative electrode occurs during the packaging or using process.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a flip-chip LED chip.

The utility model provides a flip LED chip, including the substrate and locate semiconductor layer, transparent conducting layer and the insulating protective layer on it in proper order, semiconductor layer, transparent conducting layer and insulating protective layer are formed with first through-hole, second through-hole and the third through-hole that link up its upper and lower surfaces respectively, the axis of first through-hole, second through-hole and third through-hole coincides, exposes the partial upper surface of substrate;

and the side wall surfaces of the first through hole, the second through hole and the third through hole and the exposed upper surface of the substrate are surrounded to form a thimble extending area.

As a further improvement of the utility model, the first through hole, the second through hole and the third through hole are cylindrical or inverted cone frustum shapes.

As a further improvement of the present invention, the aperture range of the first through hole, the second through hole and the third through hole is 50-200 μm.

As a further improvement of the utility model, the side wall face of the first through hole and the second through hole is covered with the insulating protective layer.

As a further improvement of the present invention, the substrate is a sapphire substrate.

As a further improvement of the utility model, flip-chip LED chip is still including locating N extension electrode on the semiconductor layer, locating P extension electrode on the transparent conducting layer and locating on the insulating protective layer with N extension electrode and P extension electrode electric connection's respectively N pad electrode and P pad electrode, first through-hole the second through-hole with the third through-hole all is located N pad electrode with between the P pad electrode, and also be located N extension electrode with between the P extension electrode.

The utility model has the advantages that: the first through hole, the second through hole and the third through hole are formed in the semiconductor layer, the transparent conducting layer and the insulating protective layer respectively to form the thimble extending area, so that the thimble can enter the front inside of the LED chip along the thimble extending area when the LED chip is jacked up, and can be abutted against a high-hardness substrate without being pierced on the thin and fragile insulating protective layer or conducting layer, thereby preventing the insulating protective layer from being pierced by the sharp thimble to cause the layer to fall off, leading the conducting layer inside the LED chip to be exposed, causing the structural integrity of the LED chip to be damaged, and causing the short circuit of a positive electrode and a negative electrode in the packaging or using process.

Drawings

Fig. 1 is a schematic diagram of a flip LED chip according to an embodiment of the present invention.

Fig. 2 is a top view of a flip LED chip according to an embodiment of the present invention.

Fig. 3 is a schematic flow chart of a method for manufacturing a flip-chip LED chip according to the present invention.

Fig. 4 to 7 are schematic diagrams illustrating steps of a method for manufacturing a flip-chip LED chip according to the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more clear, the technical solutions of the present application will be clearly and completely described below with reference to the detailed description of the present application and the accompanying drawings. It should be apparent that the described embodiments are only some embodiments of the present application, and not all embodiments. All other embodiments obtained by a person of ordinary skill in the art without any inventive work based on the embodiments in the present application are within the scope of protection of the present application.

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

For convenience in explanation, the description herein uses terms indicating relative spatial positions, such as "upper," "lower," "rear," "front," and the like, to describe one element or feature's relationship to another element or feature as illustrated in the figures. The term spatially relative position may encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "above" other elements or features would then be oriented "below" or "above" the other elements or features. Thus, the exemplary term "below" can encompass both a spatial orientation of below and above.

As shown in fig. 1, the present invention provides a flip-chip LED chip, which comprises a substrate 1, and a semiconductor layer 2, a transparent conductive layer 3 and an insulating protection layer 4 sequentially disposed thereon.

The semiconductor layer 2, the transparent conductive layer 3 and the insulating protective layer 4 are respectively provided with a first through hole 21, a second through hole 31 and a third through hole 41 which penetrate through the upper surface and the lower surface of the semiconductor layer, and the central axes of the first through hole 21, the second through hole 31 and the third through hole 41 are overlapped to expose the upper surface of the substrate 1.

The side wall surfaces of the first through hole 21, the second through hole 31 and the third through hole 41 and the exposed upper surface of the substrate 1 are surrounded to form a thimble extending area 5.

In this embodiment, the transparent conductive layer 3 is an indium tin oxide layer with a thickness ranging from 10 nm to 300 nm. In other embodiments, the material of the transparent conductive layer 3 can also be other transparent conductive materials such as aluminum-doped zinc oxide.

The insulating protective layer 4 is a single-layer structure or a distributed bragg reflector structure formed by alternately stacking a plurality of layers. In the present embodiment, the insulating protection layer 4 is a silicon dioxide layer, or a silicon nitride layer, or a distributed bragg reflector layer formed by alternately stacking titanium pentoxide and silicon dioxide layers. In other embodiments, the insulating protection layer 4 may also be another insulating material layer.

The semiconductor layer 2 comprises an N-type semiconductor layer 2a, a light emitting layer 2b and a P-type semiconductor layer 2c, and the N-type semiconductor layer 2a and the P-type semiconductor layer 2c can be an N-type gallium nitride epitaxial layer and a P-type gallium nitride epitaxial layer respectively or other common LED epitaxial layer materials. The first through hole 21 penetrates through the N-type semiconductor layer 2a, the light emitting layer 2b and the P-type semiconductor layer 2c in sequence to expose the upper surface of the substrate 1.

The flip LED chip further comprises an N extension electrode 61 arranged on the N-type semiconductor layer 2a, a P extension electrode 71 arranged on the transparent conducting layer 3, a current blocking layer 8 arranged between the P-type semiconductor layer 2c and the transparent conducting layer 3, and an N pad electrode 62 and a P pad electrode 72 which are arranged on the insulating protective layer 4 and electrically connected with the N extension electrode 61 and the P extension electrode 71 respectively.

The ejector pin 9 is a part of a die bonder, the flip LED chip can be transferred from a blue film to a substrate through the die bonder, the ejector pin 9 is arranged below a machine table of the die bonder, a suction nozzle is arranged above the machine table, the flip LED chip to be packaged is arranged on the machine table, the flip LED chip is upwards jacked up through the ejector pin 9, and then the suction nozzle moves downwards to adsorb the flip LED chip and transfers the flip LED chip to the substrate. Of course, the thimble 9 is not limited thereto, and may be a thimble used in other subsequent production processes or testing processes.

The aperture of the first through hole 21, the second through hole 31 and the third through hole 41 is larger than the diameter of the thimble 9, so that the thimble 9 can penetrate into the flip-chip LED chip along the third through hole 41, the second through hole 31 and the first through hole 21 in sequence to jack the flip-chip LED chip.

Further, in the present embodiment, the first through hole 21, the second through hole 31 and the third through hole 41 are located at a central position of the flip LED chip to adapt to a position where the thimble 9 is pushed up.

Furthermore, the first through hole 21, the second through hole 31 and the third through hole 41 are located between the N pad electrode 62 and the P pad electrode 72 and between the N extension electrode 61 and the P extension electrode 71, and do not pass through the current blocking layer 8 located below the P extension electrode 71, so as to reduce the influence on the existing flip LED chip structure, avoid the process from being too complicated and reduce the influence on the light emitting efficiency of the flip LED chip.

In other embodiments, the positions of the first through hole 21, the second through hole 31 and the third through hole 41 may also be specifically adjusted according to the working position of the thimble 9.

Specifically, the first through hole 21, the second through hole 31, and the third through hole 41 are cylindrical or truncated cone, the aperture of the second through hole 31 is greater than or equal to the aperture of the first through hole 21, and the aperture ranges of the first through hole 21, the second through hole 31, and the third through hole 41 are 50-200 μm. When the first through hole 21, the second through hole 31 and the third through hole 41 are in the shape of an inverted truncated cone, the aperture is the aperture at the minimum position of the truncated cone. Because the diameter of the thimble 9 in the current die bonder is generally a needle-shaped structure of 50 μm, the shapes of the first through hole 21, the second through hole 31 and the third through hole 41 of the structure are more adapted to the thimble 9, so as to reduce the space occupied by the through holes in the flip-chip LED chip and reduce the influence of the through holes on the light emitting efficiency of the flip-chip LED chip.

Of course, in other embodiments of the present invention, the shapes and sizes of the first through hole 21, the second through hole 31 and the third through hole 41 may be adaptively adjusted according to the specific size of the thimble 9.

In the present embodiment, the substrate 1 is a sapphire substrate, the sapphire substrate has a high hardness, and the regions exposed in the first through hole 21, the second through hole 31, and the third through hole 41 are in contact with the thimble 9, so that the thimble 9 pierces the high-hardness substrate 1. In other embodiments, the substrate 1 may be the substrate for the flip-chip LED chip, such as silicon or silicon carbide.

Expose through the setting substrate 1 first through-hole 21 second through-hole 31 with third through-hole 41 can make thimble 9 is in jack-up during the flip-chip LED chip, follow thimble 9 stretches into the district and enters into the positive inside of flip-chip LED chip offsets in high rigidity substrate 1, and can not pierce on thin and fragile insulating protective layer 4 or conducting layer, in order to avoid insulating protective layer 4 is pricked by sharp-pointed thimble 9 and makes this layer drop, leads to the inside conducting layer of flip-chip LED chip exposes, makes the structural integrity of flip-chip LED chip suffers destruction, appears positive negative pole short circuit condition in encapsulation or use, causes encapsulation lamp pearl to become invalid.

In some embodiments of the present invention, the first through hole 21 and the side wall surface of the second through hole 31, and the semiconductor layer 2 is exposed in the region of the second through hole 31 is covered with the insulating protection layer 4, so that the region where the thimble 9 goes deep is covered with the insulating protection layer 4 to realize insulating protection, thereby avoiding the occurrence of contact short circuit in the manufacturing process and the occurrence of short circuit inside the chip.

It is understood that the hole diameters of the first through hole 21 and the second through hole 31 covered with the insulating protective layer 4 refer to the distance length between the insulating protective layers 4 on the opposite sides.

As shown in fig. 2, the present invention further provides a method for manufacturing the flip LED chip, comprising the steps of:

s1: as shown in fig. 3, a substrate 1 is provided, a semiconductor layer 2 is grown on the substrate 1, and a first through hole 21 is formed through the upper and lower surfaces of the semiconductor layer 2 to expose the substrate 1.

In this embodiment, the substrate 1 is a sapphire substrate, and in other embodiments, the substrate 1 may be the substrate 1 for a flip-chip LED chip, which is a common substrate for a flip-chip LED, such as silicon or silicon carbide.

Growing the semiconductor layer 2 includes sequentially growing an N-type semiconductor layer 2a, a light emitting layer 2b, and a P-type semiconductor layer 2 c. And etching part of the light emitting layer 2b and the P-type semiconductor layer 2c to expose the region of the N-type semiconductor layer 2a where the extension electrode is arranged. And etching the N-type semiconductor layer 2a, the light emitting layer 2b and the P-type semiconductor layer 2c to form the first through hole 21.

The first through hole 21 is cylindrical or inverted cone frustum-shaped, and the aperture range of the first through hole 21 is 50-200 μm.

S2: as shown in fig. 4, a transparent conductive layer 3 is formed on the semiconductor layer 2, and a second via hole 31 penetrating through the upper and lower surfaces of the transparent conductive layer 3 is formed in the transparent conductive layer 3, wherein at least the first via hole 21 is exposed from the second via hole 31.

Specifically, in the present embodiment, the forming of the second through hole 31 includes: after the transparent conductive layer 3 is formed by vapor deposition, a pattern and the second through hole 31 are formed by etching.

The second through hole 31 is cylindrical or inverted cone frustum-shaped, the aperture range of the second through hole 31 is 50-200 μm, and is greater than or equal to the diameter of the first through hole 21.

In some embodiments of the present invention, depositing the transparent conductive layer 3 further comprises depositing a current blocking layer 8 on the P-type semiconductor layer 2 c.

S3: as shown in fig. 5, a P extension electrode 71 is formed on the transparent conductive layer 3, an N extension electrode 61 is formed on the semiconductor layer 2, an insulating protective layer 4 is formed on the conductive layer and the N extension electrode 61 and the P extension electrode 71, and a third via hole 41 is formed on the insulating protective layer 4.

Specifically, in the present embodiment, the forming of the extension electrode includes: an N extension electrode 61 is formed on the N-type semiconductor layer 2a by evaporation, and a P extension electrode 71 is formed on the transparent conductive layer 3 by evaporation.

In the present embodiment, forming the insulating protection layer 4 specifically includes: depositing a layer of silicon dioxide or silicon nitride to form a single-layer insulating protective layer 4 or alternately depositing titanium pentoxide and silicon dioxide to form a distributed Bragg reflection layer. In other embodiments, the insulating protection layer 4 may also be another insulating material layer.

The insulating protective layer 4 is also deposited on the side wall surfaces of the first via hole 21 and the second via hole 31 and on the region of the semiconductor layer 2 exposed to the second via hole 31.

S4: as shown in fig. 6, an N pad electrode 62 and a P pad electrode 72 are formed on the insulating protective layer 4.

And an N pad electrode 62 and a P pad electrode 72 electrically connected to the N extension electrode 61 and the P extension electrode 71, respectively, are vapor-deposited on the insulating protective layer 4.

To sum up, the utility model discloses a semiconductor layer transparent conducting layer with set up respectively on the insulating protective layer first through-hole the second through-hole with the third through-hole forms the thimble and stretches into the district, can make the thimble is when jack-up LED chip, follows the thimble stretches into the district and enters into LED chip openly inside, offsets in the high rigidity the substrate, and can not stab on thin and fragile insulating protective layer or conducting layer, in order to avoid insulating protective layer is pricked by sharp-pointed thimble and makes this layer drop, leads to the inside conducting layer of LED chip to expose, makes the structural integrity of LED chip suffer destruction, appears positive negative pole short circuit condition in encapsulation or use.

It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.

The above list of details is only for the feasible embodiments of the present invention, and is not intended to limit the scope of the present invention, and all equivalent embodiments or modifications that do not depart from the technical spirit of the present invention are intended to be included within the scope of the present invention.

Claims

1. A flip LED chip comprises a substrate, and a semiconductor layer, a transparent conductive layer and an insulating protective layer sequentially arranged on the substrate,

a first through hole, a second through hole and a third through hole which penetrate through the upper surface and the lower surface of the semiconductor layer, the transparent conducting layer and the insulating protection layer are respectively formed, and the central axes of the first through hole, the second through hole and the third through hole are superposed to expose part of the upper surface of the substrate;

2. The flip LED chip of claim 1, wherein the first, second, and third vias are cylindrical or inverted frustoconical.

3. The flip LED chip of claim 2, wherein the first, second, and third vias have an aperture in the range of 50-200 μ ι η.

4. The flip LED chip of claim 1, wherein the side walls of the first and second vias are covered with the insulating protective layer.

5. The flip LED chip of claim 1, wherein the substrate is a sapphire substrate.

6. The flip LED chip of claim 1, further comprising an N extension electrode disposed on the semiconductor layer, a P extension electrode disposed on the transparent conductive layer, and an N pad electrode and a P pad electrode disposed on the insulating protective layer and electrically connected to the N extension electrode and the P extension electrode, respectively, wherein the first through hole, the second through hole, and the third through hole are disposed between the N pad electrode and the P pad electrode and also between the N extension electrode and the P extension electrode.