CN109755372B

CN109755372B - LED substrate, LED chip, manufacturing method of LED chip, LED lamp source and display device

Info

Publication number: CN109755372B
Application number: CN201711068137.0A
Authority: CN
Inventors: 李振宁; 张志宽; 邢其彬
Original assignee: Shenzhen Jufei Optoelectronics Co Ltd
Current assignee: Shenzhen Jufei Optoelectronics Co Ltd
Priority date: 2017-11-03
Filing date: 2017-11-03
Publication date: 2021-05-11
Anticipated expiration: 2037-11-03
Also published as: CN109755372A

Abstract

The embodiment of the disclosure relates to an LED substrate, an LED chip, a manufacturing method of the LED chip, an LED lamp source and a display device. The manufacturing method of the LED substrate comprises the following steps: before cutting a substrate body carrying a plurality of LED chip units, removing the electroplated lead layers on the two sides outside a preset cutting area of the substrate body. According to the method, the electroplating lead layers on the two sides of the preset cutting area of the substrate body are removed before cutting, so that the electroplating lead layers cannot be exposed on the side face of the LED chip in the finally obtained LED chip, and the air tightness of the LED chip is improved.

Description

LED substrate, LED chip, manufacturing method of LED chip, LED lamp source and display device

Technical Field

The embodiment of the disclosure relates to the field of LEDs, in particular to an LED substrate and a manufacturing method thereof, an LED chip and a manufacturing method thereof, an LED lamp source and a display device.

Background

In the existing chip-level small-pitch LED (Light Emitting Diode) device packaging technology, a flat substrate is used as an LED support, after die bonding and wire bonding are performed on the substrate, molding is performed by means of molding, and finally, individual LED chips are cut by means of a cutting process. The surface of the substrate used by the product with the structure is usually electroplated with metals such as nickel, silver, gold and the like, and in the electroplating process, areas of the substrate needing to be electroplated are electrified, so that functional areas of the substrate are connected with electroplating leads. After the die bonding, wire bonding and molding are completed on the substrate, the electroplating leads are cut when the substrate is cut into single LED chips, so that the metal electroplating leads are exposed on the side surfaces of the finished LED chips.

Fig. 1 and 2 show a process for fabricating LED chips and a side view of the resulting chips in accordance with a prior art fabrication process; firstly, forming a plurality of metal functional layers of LED chip units on the upper surface of a base material 11; the metal functional layers may include a plating lead layer 12a, a bonding wire functional layer 12b, and a die bond functional layer 12 c; in addition, conductive pins 14 are formed on the lower surface of the substrate 11, and the conductive pins 14 are connected with the metal functional layer through conductive through holes (not shown in the figure); a light emitting structure 13 (not shown in fig. 1) is formed on the metal functional layer on the upper surface, and the light emitting structure 13 includes an LED chip fixed on the metal functional layer by die bonding, and a colloid formed by sealing glue on the upper surface after die bonding. Thus, an LED substrate shown in fig. 1 (a) is obtained, and then the LED substrate is diced to obtain LED chips shown in fig. 1(b) and fig. 2. In the LED chip obtained in this way, the plated lead layer 12a extends to the edge of the LED chip, so the end of the plated lead layer 12a is exposed to the side surface of the LED chip after the molding. Because the metal part of the LED chip and the LED external sealing adhesive have poor bonding performance, the LED has poor air tightness, and water vapor in the environment easily permeates into the LED along the electroplating lead, so that the LED is affected with damp, and the problems of lamp death, electric leakage and the like occur in the surface mounting process or the terminal application process.

Disclosure of Invention

A primary object of at least one embodiment of the present disclosure is to improve the hermeticity of an LED chip.

In a first aspect, an embodiment of the present disclosure provides a method for manufacturing an LED substrate, where the method includes:

before cutting a substrate body carrying a plurality of LED chip units, removing the electroplated lead layers on the two sides outside a preset cutting area of the substrate body.

Optionally, the removing the plating lead layer on the two sides outside the preset cutting area of the substrate body includes:

determining a polishing area comprising the preset cutting area, wherein a spacing distance is arranged between the boundary of the preset cutting area and the boundary of the polishing area;

and polishing off the electroplating lead layer in the polishing area in a polishing mode.

Optionally, the polishing the plated lead layer in the polishing area by polishing includes:

polishing off the electroplating lead layer in the polishing area by using a polishing blade;

alternatively, the first and second electrodes may be,

determining the grinding depth; the polishing depth is greater than the thickness of the electroplating lead layer and less than the sum of the thickness of the electroplating lead layer and the thickness of the substrate body; and according to the polishing depth, polishing the polishing area by using a polishing blade so as to polish off the electroplating lead layer in the polishing area.

Optionally, before the sealing of the LED chip unit on the substrate body, removing the electroplated lead layers on the two sides outside the preset cutting area of the substrate body;

alternatively, the first and second electrodes may be,

before die bonding is carried out on the LED chip units on the substrate body, the electroplating lead layers on the two sides outside the preset cutting area of the substrate body are removed.

Optionally, the method further comprises:

and after the electroplating lead layers on the two sides outside the preset cutting area of the substrate body are removed, cleaning the surface of the substrate body.

In a second aspect, an embodiment of the present disclosure provides an LED substrate, including: a substrate body, a metal functional layer formed on the substrate body, and a light emitting structure formed on the metal functional layer,

each metal functional layer comprises a die bonding functional layer, a bonding wire functional layer and an electroplating lead layer; and a spacing distance is arranged between the electroplating lead layer and the adjacent preset cutting area boundary on the substrate body.

In a third aspect, an embodiment of the present disclosure provides a method for manufacturing an LED chip, including:

fabricating an LED substrate according to the method of any one of claims 1 to 6;

and cutting the preset cutting area to obtain a plurality of LED chips.

In a fourth aspect, an embodiment of the present disclosure provides an LED chip, including: a substrate and a metal functional layer formed on the substrate,

the metal functional layer comprises a die bond functional layer, a bonding wire functional layer and an electroplating lead layer, and a spacing distance is arranged between the electroplating lead layer and the side face of the base material.

In a fifth aspect, an embodiment of the present disclosure provides an LED light source, including: the LED chip of the fourth aspect.

In a sixth aspect, an embodiment of the present disclosure provides a display device, which includes the LED lamp source according to the fifth aspect and/or the LED chip according to the fourth aspect.

According to the LED substrate manufacturing method provided by the embodiment of the application, the electroplating lead layers on the two sides outside the preset cutting area of the substrate body are removed before cutting, so that the electroplating lead layers cannot be exposed on the side faces of the LED chip in the finally obtained LED chip, the air tightness of the LED chip is improved, the LED chip cannot be affected with damp, the problems of lamp death, electric leakage and the like in the chip mounting process or the terminal application process are solved, and the service life of the LED is prolonged.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.

FIG. 1 shows a schematic diagram of prior art LED substrate fabrication;

FIG. 2 is a side view of an LED chip made using the prior art;

fig. 3 is a schematic diagram of a front surface structure of a substrate according to an embodiment of the present disclosure;

fig. 4 is another schematic view of another front side structure of a substrate according to an embodiment of the present disclosure;

FIG. 5 is a schematic structural diagram of an LED chip obtained after the substrate shown in FIG. 4 is cut;

FIG. 6 is a side view of the LED chip cut from FIG. 5;

fig. 7 is a schematic flow chart illustrating another substrate manufacturing method according to an embodiment of the present disclosure;

FIG. 8 is a schematic view of the structure of the substrate after the polishing area is determined;

fig. 9 is a side view of the LED chip obtained after cutting in fig. 8.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In a first aspect, an embodiment of the present disclosure provides a method for manufacturing an LED substrate, where the method includes: before cutting a substrate body carrying a plurality of LED chip units, removing the electroplated lead layers on the two sides outside a preset cutting area of the substrate body. Regarding other steps of manufacturing the LED substrate, reference may be made to the prior art, and detailed description thereof is omitted.

Fig. 3 is a schematic front structure diagram of a substrate according to an embodiment of the present disclosure.

As shown in fig. 3, the substrate includes: the LED light source comprises a substrate body 10 and a metal functional layer 12 of a plurality of LED chip units arranged on the front surface of the substrate body 10, wherein the substrate body 10 is used as a carrier for carrying and realizing the LED chip units and other electrical elements. The material of the substrate body 10 may be BT resin, ceramic, or other non-conductive material.

A metal functional layer 12 is fixed on the upper surface, the metal functional layer 12 including: a plating lead layer 12a, a die bond functional layer 12c, and a wire bond functional layer 12 b. It can be understood that the die bonding functional layer 12c is mainly used for subsequent die bonding, and correspondingly, the bonding wire functional layer 12b is mainly used for subsequently connecting two ends of a gold wire to the positive electrode block and the negative electrode block to form a connector. The specific structures of the die bond functional layer 12c and the wire bond functional layer 12b can be referred to in the prior art, and will not be described in detail herein.

Fig. 3 illustrates only 4 LED chip units, and in practical applications, generally, thousands of LED chip units can be mounted on the substrate body. In order to obtain individual LED chips, the substrate needs to be cut, and in fig. 3, the area shown by the dotted line is a preset cutting area 12d, and there are generally four preset cutting areas 12d around one LED chip unit, and the width of the preset cutting area 12d is d.

In fig. 3, the widths of the different preset cutting regions are all set to be d, and in other embodiments, the widths of the different preset cutting regions on the substrate body can also be freely set, for example: set as d1, d2, d3 … …, etc., respectively.

In the method provided by the embodiment of the application, before the substrate shown in fig. 3 is cut, the plated lead layers on the two sides outside the preset cutting area are also removed. In the embodiment of the present application, the removal of the plating lead layer refers to the physical removal of the plating lead layer, for example: by means of blade cutting or blade grinding.

Fig. 4 is a schematic diagram illustrating the removal of the plating lead layer outside the predetermined cutting region.

As can be seen from the figure, the area shown by 12e is the area where the plating lead layer is removed, and as can be seen from the figure, the plating lead layer on the two sides outside each preset cutting area is removed, that is, a spacing distance is set between the plating lead layer and the adjacent preset cutting area, and the size of the spacing distance can be freely set by those skilled in the art.

Fig. 5 shows 4 LED chips obtained by cutting the substrate shown in fig. 4 along a predetermined cutting region. Fig. 6 is a side view of the LED chip obtained after dicing.

As shown in fig. 5, in the LED chip obtained by cutting in the figure, a spacing distance is provided between the side surfaces of the LED chips on the plated lead layers, and further as shown in fig. 6, the plated lead layers are not exposed on the side surfaces of the LED chips, 11 in fig. 6 is a base material of the LED chips, and 14 is a conductive pin.

Fig. 7 is a schematic flow chart illustrating another substrate manufacturing method according to an embodiment of the present disclosure.

As shown in fig. 7, the method may include the steps of:

and S101, determining a polishing area containing the preset cutting area.

Fig. 8 is a schematic view of a structure of a substrate defining a polishing area. As shown in fig. 8, 12f is a grinding area and the width of the grinding area is f, f > d can be seen from the figure, and a spacing distance is arranged between the boundary of the preset cutting area 12e and the boundary of the grinding area 12f, namely the preset cutting area is positioned in the grinding area and does not coincide with the side edge of the grinding area, and when the center lines of the grinding area and the cutting area coincide, (f-d)/2 > 0.

In practical applications, the determination of the sanding area may be achieved by selecting a sanding blade, in particular a sanding blade having a thickness greater than the thickness of the cutting blade.

And S102, polishing off the electroplating lead layer in the polishing area in a polishing mode.

In the specific implementation of this step, the following may be implemented:

the first method is as follows: and polishing off the electroplating lead layer in the polishing area by using a polishing blade.

The thickness of the polishing is completely equal to the thickness of the plated lead layer, and by this polishing, the plated lead layer can be completely removed without leaving any trace on the substrate body.

The second method comprises the following steps: the method comprises the following steps:

and S1, determining the grinding depth.

The grinding depth here means a depth of grinding of the grinding blade toward the inside of the substrate from the start of grinding to the end of grinding. In the embodiment of the application, the polishing depth is generally larger than the thickness of the electroplating lead layer, and in addition, the polishing depth is also smaller than the sum of the thickness of the electroplating lead layer and the thickness of the substrate body so as to avoid polishing the substrate body to penetrate. Adopt above-mentioned mode of polishing, consider the high difference on electroplating lead layer, some places are than thin, and some places are than thicker, so the mode of polishing that no longer leaves the vestige on the base plate body is controlled comparatively difficultly, in order to raise the efficiency, can select to polish base plate body part when polishing, can set up a depth of polishing like this can.

And S2, polishing the polishing area by using a polishing blade according to the polishing depth so as to polish off the electroplating lead layer in the polishing area.

By this polishing method, a polishing groove can be formed in the polishing region after polishing, as shown in fig. 9, which is a side view of the LED chip formed by this method after polishing and cutting, and it can be seen that the polishing groove 12g is formed on the base material 11 of the LED chip. By controlling the grinding depth, the depth of the grinding groove 12g is generally smaller than the thickness of the substrate 11.

In the method for manufacturing the substrate provided by the embodiment of the application, the step of removing the electroplated lead layers on the two sides outside the preset cutting area of the substrate body can be performed before sealing the LED chip units on the substrate body with glue or before die bonding the LED chip units on the substrate body, but no matter how the process is adjusted, the step of removing the electroplated lead layers on the two sides outside the preset cutting area of the substrate body must be performed before sealing the glue, otherwise, the problem that the electroplated lead layers are exposed on the side surfaces of the LED chips when the electroplated lead layers are removed after sealing the glue still occurs.

In addition, after the electroplated lead layers on the two sides outside the preset cutting area of the substrate body are removed, the method can further comprise the following steps: and cleaning the surface of the substrate body. To clean away metal or other debris formed during the sanding process.

Because water, alcohol or other liquids are needed to be used for washing the surface of the substrate body during cleaning, and considering that the liquids can corrode the LED wafer, optionally, in an embodiment of the present application, the electroplated lead layer can be removed before die bonding, so that the electroplated lead layer is removed and die bonding is performed after cleaning, corrosion of the cleaning liquid to the LED wafer can be reduced, and the problem that the LED wafer is damaged due to contact with the cleaning liquid is avoided.

In a second aspect, an embodiment of the present disclosure provides an LED substrate, whose main structure can refer to the structures shown in fig. 4, 5, and 6, including:

the light emitting device comprises a substrate body 10, a metal functional layer formed on the substrate body 10, and a light emitting structure 13 formed on the metal functional layer; the metal functional layer comprises a solid crystal functional layer, a bonding wire functional layer and an electroplating lead layer;

and a spacing distance is arranged between the electroplating lead layer and the adjacent preset cutting area boundary on the substrate body.

In implementation, the process of forming the metal functional layer on the substrate body 10 may refer to the prior art, for example, a metal film with a certain thickness may be formed in a deposition manner, and then a metal structure outside the metal functional layer is removed by an etching process to obtain the metal functional layer and the conductive pin.

In the LED substrate provided by the embodiment of the present disclosure, the manufacturing process of fig. 3 to 5 and fig. 6 may be referred to for the LED chip obtained after being cut; the substrate body 10 is cut into a plurality of base materials 11, that is, each LED chip has a separate base material 11, and the distance between the plating lead layer and the side surface of the base material 11 is (f-d)/2, that is, the plating lead layer 12a does not extend to the side surface of the LED chip, so that the plating lead layer can be prevented from being exposed to the air, which helps to improve the air tightness of the LED chip.

The LED substrate provided by the embodiment of the present disclosure can be manufactured by the method of any one of the first aspect. The specific structure of the LED substrate obtained when manufactured by the corresponding method can be referred to the description of the first aspect, and will not be described in detail here.

In a third aspect, an embodiment of the present disclosure further provides a method for manufacturing an LED chip, where the method mainly includes:

first, an LED substrate is fabricated according to the method of any one of the first aspect. The detailed manufacturing process is described with reference to the first aspect, and will not be described in detail here.

Secondly, cutting the preset cutting area on the LED substrate to obtain a plurality of LED chips; wherein, this LED base plate is the LED base plate of second aspect.

The specific process of cutting the LED substrate can refer to the prior art, and is not further described here.

Referring to fig. 6, in the LED chip manufactured by the LED chip manufacturing method provided by the embodiment of the disclosure, the plated lead layer 12a does not extend to the side surface of the LED chip, so that the plated lead layer is prevented from being exposed in the air, which is helpful to improve the air tightness of the LED chip.

The specific process of cutting the LED substrate may refer to the prior art, and the embodiment of the disclosure is not described in detail.

In a fourth aspect, an embodiment of the present disclosure further provides an LED chip, where a main structure of the LED chip may refer to fig. 6 or fig. 9, and the LED chip may include:

a substrate 11, a metal functional layer formed on the substrate, and a light emitting structure 13 formed on the metal functional layer; the metal functional layer comprises a solid crystal functional layer 12c, a welding wire functional layer 12b and an electroplating lead layer 12 a;

wherein a spacing distance is arranged between the electroplating lead layer and the side surface of the base material.

According to the LED chip provided by the embodiment of the disclosure, the electroplating lead layer is not exposed in the air, and the air tightness of the LED chip is improved.

The LED chip provided by the embodiment of the present disclosure may be an LED chip manufactured by the method according to any one of the third aspect. When the LED chip is manufactured by the corresponding method, the specific structure of the LED chip obtained can be referred to the description of the third aspect, and will not be described in detail here.

In a fifth aspect, embodiments of the present disclosure further provide an LED lamp source, which includes the LED chip of any one of the fourth aspects. The LED light source can specifically refer to an LED light bar, a lamp, a backlight source and the like. In one embodiment, the LED light source may include a PCB, and each LED chip is mounted to the PCB by solder paste to form an LED light source comprising a plurality of LED chips.

In a sixth aspect, the disclosed embodiments further provide a display device, and a backlight device of the display device includes one or more combinations of the LED light source of the fifth aspect and the LED chip of the fourth aspect.

In a specific implementation, the display device may be a display screen or a display of a mobile phone, a tablet computer, a personal computer, a smart watch, or the like.

It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The foregoing are merely exemplary embodiments of the present invention, which enable those skilled in the art to understand or practice the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A manufacturing method of an LED substrate is characterized by comprising the following steps:

before cutting a substrate body carrying a plurality of LED chip units, removing the electroplated lead layers on the two sides outside a preset cutting area of the substrate body;

wherein, get rid of the electroplating lead layer of the outer both sides of base plate body preset cutting area includes:

and removing the electroplating lead layer in the grinding area.

2. The method of claim 1, wherein the removing the plated lead layers outside the predetermined cut region of the substrate body comprises:

3. The method of claim 2, wherein polishing away the plated lead layer in the polished area by polishing comprises:

alternatively, the first and second electrodes may be,

4. The method of claim 1,

before sealing the LED chip unit on the substrate body, removing the electroplating lead layers on the two sides outside the preset cutting area of the substrate body;

alternatively, the first and second electrodes may be,

5. The method of claim 1 or 4, further comprising:

6. An LED substrate, comprising: the light-emitting structure comprises a substrate body, a metal functional layer formed on the substrate body and a light-emitting structure formed on the metal functional layer;

7. A method for manufacturing an LED chip is characterized by comprising the following steps:

fabricating an LED substrate according to the method of any one of claims 1 to 5;

and cutting the preset cutting area to obtain a plurality of LED chips.

8. An LED chip, comprising: a substrate, a metal functional layer formed on the substrate, and a light emitting structure formed on the metal functional layer;

9. An LED light source, comprising: the LED chip of claim 8.

10. A display device, characterized in that the display device comprises the LED lamp source according to claim 9 and/or the LED chip according to claim 8.