Light-emitting device

Abstract

The utility model relates to the technical field of semiconductor light emitting, and discloses a light-emitting device, which comprises a substrate, a light-emitting chip, a light-transmitting glue layer and a fluorescent glue layer. The light-emitting chip is arranged on the substrate. The light-transmitting glue layer at least covers the upper surface of the substrate. The fluorescent glue layer at least covers the upper surface of the light-transmitting glue layer. According to the light-emitting device, the light-transmitting glue layer is additionally arranged between the light-emitting chip and the fluorescent glue layer, the thickness difference of the light-emitting chip is compensated by the light-transmitting glue layer, and the thickness consistency of the fluorescent glue layers formed in batches is ensured, so that the color of emitted light is consistent and uniform, and the quality of the light-emitting device is stable. Light diffusion particles are additionally arranged in the light-transmitting glue layer, so that the heat conductivity and the light emitting uniformity can be improved. The personalized arrangement of the structure of the first optical interface enables the color of a single light-emitting device to be more uniform, reduces the problem that the light-emitting colors of the peripheral edge and the middle part are inconsistent, and is easy for optical design.

Description

Technical Field

[0001] The utility model belongs to the technical field of semiconductor light emitting, and particularly relates to a light emitting device. Background Art

[0002] In the fabrication of light emitting devices, to change the emitted light color, a fluorescent glue layer 4 is usually covered on the light emitting surface of the light emitting chip 2, as shown in Figure 8 . In the first step of forming the fluorescent glue layer 4, the fluorescent glue is drop - applied onto the upper surface of the light emitting chip 2 fixed on the substrate 1, as shown in Figure 6 . In the second step of forming the fluorescent glue layer 4, the fluorescent glue is pressed onto the upper surface of the light emitting chip 2 by a mold 6, as shown in Figure 7 . After curing, the mold 6 is removed to obtain the light emitting device of the prior art, as shown in Figure 8 .

[0003] Generally, the incoming thickness of the light emitting chip 2 is inconsistent. When the height of the mold 6 for forming the fluorescent glue layer 4 is fixed, the height of the light emitting surface of the thicker light emitting chip 2 is higher, and the formed fluorescent glue layer 4 on it is thinner; the height of the light emitting surface of the thinner light emitting chip 2 is lower, and the formed fluorescent glue layer 4 on it is thicker. The light emitting devices with fluorescent glue layers 4 of different thicknesses emit light of inconsistent colors. When spliced and used in combination, for example, it will cause the white light color points emitted after the blue light chip is excited by the fluorescent glue layer to be not concentrated, affecting the color consistency of the entire light field.

[0004] In addition, there is an inconsistent situation in the light emission color between the middle part and the four - week edges of the existing single light emitting device. For example, the white light emitted after the blue light chip is excited by the fluorescent glue layer shows a yellowish phenomenon at the edge.

[0005] Based on the above, the current problem to be solved is to provide a light emitting device with uniform light emission, consistent color, and stable product quality. Summary of the Utility Model

[0006] The purpose of the utility model is to provide a light emitting device, aiming at solving the problems in the prior art that the light emission of the light emitting device after the action of the fluorescent glue layer is uneven, the color is inconsistent, and the product quality is unstable.

[0007] The utility model is realized as follows. The light emitting device includes:

[0008] A substrate;

[0009] A light emitting chip, which is arranged on the substrate;

[0010] A light - transmitting glue layer, which covers at least the upper surface of the light emitting chip;

[0011] A fluorescent glue layer, which covers at least the upper surface of the light - transmitting glue layer;

[0012] Among them, the light-transmitting adhesive layer is used to make up for the thickness difference of the light-emitting chip, so that the thickness of the batch-formed fluorescent adhesive layer is consistent.

[0013] Furthermore, the light-transmitting adhesive layer includes light-diffusing particles.

[0014] Furthermore, a first optical interface is provided on one side of the light-transmitting adhesive layer close to the fluorescent adhesive layer, and the first optical interface is set as a plane or / and a curved surface.

[0015] Furthermore, the first optical interface is set as a micro-curved surface recessed into the light-transmitting adhesive layer, and the thickness distribution of the light-transmitting adhesive layer gradually becomes thicker from the middle to the four peripheral edges.

[0016] Furthermore, the first optical interface is set as a micro-curved surface protruding towards the fluorescent adhesive layer, and the thickness distribution of the light-transmitting adhesive layer gradually becomes thinner from the middle to the four peripheral edges.

[0017] Furthermore, the first optical interface includes a plane in the middle and inclined planes or curved surfaces at the four peripheral edges, and the thickness distribution of the light-transmitting adhesive layer is thin in the middle and gradually becomes thicker at the four peripheral edges.

[0018] Furthermore, a second optical interface for outputting light is provided on one side of the fluorescent adhesive layer away from the light-transmitting adhesive layer; the second optical interface is set as a plane or / and a curved surface.

[0019] Furthermore, the thickness of the light-transmitting adhesive layer is set to 20-60 um.

[0020] Furthermore, a high-reflection adhesive layer is provided around the light-emitting chip, the light-transmitting adhesive layer and the fluorescent adhesive layer.

[0021] Compared with the prior art, a light-emitting device provided by the present utility model has the following beneficial effects:

[0022] 1. By adding a light-transmitting adhesive layer 3 between the light-emitting chip 2 and the fluorescent adhesive layer 4, the present utility model makes up for the thickness difference of the incoming light-emitting chip 2 with the light-transmitting adhesive layer 3. The light-transmitting adhesive layer 3 and the fluorescent adhesive layer 4 are successively formed by mechanical die pressing. The die has high precision, ensuring that the thickness of the batch-formed fluorescent adhesive layer 4 is consistent, so that the light output color is consistent and uniform, and the quality of the light-emitting device is stable.

[0023] 2. Adding light-diffusing particles in the light-transmitting adhesive layer 3 can increase the thermal conductivity and improve the light output uniformity.

[0024] 3. To cooperate with glues of different color temperatures and viscosities, etc., the first optical interface 31 can be set as a plane or / and a curved surface. The personalized setting of the structure of the first optical interface 31 makes the color of a single light-emitting device more uniform, reduces the problem of inconsistent light-emitting colors between the four peripheral edges and the middle part, and is easy for optical design. Description of the Drawings

[0025] Figure 1 is a schematic cross-sectional structure diagram of the light-emitting device provided by the present utility model;

[0026] Figure 2 is a schematic cross-sectional structure diagram of the light-emitting device of Embodiment 1 provided by the present utility model;

[0027] Figure 3 is a schematic cross-sectional structure diagram of the light-emitting device of Embodiment 2 provided by the present utility model;

[0028] Figure 4 is a schematic cross-sectional structure diagram of the light-emitting device of Embodiment 3 provided by the present utility model;

[0029] Figure 5 is a schematic cross-sectional structure diagram of the light-emitting device of Embodiment 4 provided by the present utility model;

[0030] Figure 6 is a schematic cross-sectional structure diagram after the implementation of Step 1 of the formation of the fluorescent glue layer in the prior art;

[0031] Figure 7 is a schematic cross-sectional structure diagram after the implementation of Step 2 of the formation of the fluorescent glue layer in the prior art;

[0032] Figure 8 is a schematic cross-sectional structure diagram of the light-emitting device provided by the prior art;

[0033] In the figure: 1 - substrate; 2 - light-emitting chip; 3 - light-transmitting glue layer; 31 - first optical interface; 4 - fluorescent glue layer; 41 - second optical interface; 5 - high-reflection glue layer; 6 - mold. Detailed Embodiments

[0034] In order to make the objectives, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0035] The implementation of the present utility model will be described in detail below with reference to specific embodiments.

[0036] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the accompanying drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the accompanying drawings are only for illustrative purposes and cannot be understood as a limitation of this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0037] Referring to Figures 1-5 as shown, it is a preferred embodiment provided by the present invention.

[0038] The light-emitting device includes a substrate 1, a light-emitting chip 2, a fluorescent glue layer 4, and a light-transmitting glue layer 3 filled between the light-emitting chip 2 and the fluorescent glue layer 4 to compensate for the influence of the thickness of the light-emitting chip 2 (referring to Figure 1 ), that is, the light-transmitting glue layer 3 and the fluorescent glue layer 4 are sequentially bonded tightly above the light-emitting chip 2.

[0039] The manufacturing steps of the light-emitting device specifically include:

[0040] Step 1: Fix the light-emitting chip 2 on the substrate 1;

[0041] Step 2: Drop the light-transmitting glue on the lower surface of the first mold or the upper surface of the light-emitting chip 2;

[0042] Step 3: Press the light-transmitting glue onto the upper surface of the light-emitting chip 2 with the first mold. After curing, remove the first mold to form the light-transmitting glue layer 3 on the upper surface of the light-emitting chip 2;

[0043] Step 4: Press the fluorescent glue onto the upper surface of the light-transmitting glue layer 3 with the second mold. After curing, remove the second mold to form the fluorescent glue layer 4 on the light-transmitting glue layer 3.

[0044] The present invention preforms the light-transmitting glue layer 3 before the fluorescent glue layer 4, which can compensate for the influence caused by the thickness difference of the incoming light-emitting chip 2. The light-transmitting glue layer 3 and the fluorescent glue layer 4 are formed by mechanical mold pressing, and the mold accuracy is relatively high, so that the total height of the light-emitting chip 2 and the light-transmitting glue layer 3 is basically the same before forming the fluorescent glue layer 4, ensuring the consistency of the thickness of the formed fluorescent glue layer 4, and further ensuring the consistency of the light-emitting color and the stable quality of the light-emitting device. The thickness of the light-transmitting glue layer 3 can be 20 - 60 um. Preferably, light-diffusing particles are added to the light-transmitting glue layer 3, which can increase the thermal conductivity and improve the light-emitting uniformity.

[0045] The light-transmitting adhesive layer 3 is provided with a first optical interface 31 on the side close to the fluorescent adhesive layer 4. The side of the fluorescent adhesive layer 4 away from the light-transmitting adhesive layer 3 is provided with a second optical interface 41 for outputting light, and the second optical interface 41 is set as a plane or / and a curved surface. To match different color temperatures or adhesives with different concentrations, etc., the first optical interface 31 is set as a plane or / and a curved surface to achieve the effect of uniform light output, which is more conducive to optical adjustment.

[0046] Specifically, the first optical interface 31 can be set as a micro-curved surface recessed into the light-transmitting adhesive layer 3. Refer to Figure 2 , the thickness distribution of the light-transmitting adhesive layer 3 gradually thickens from the middle to the four peripheral edges. When the second optical interface 41 is set as a plane, the above setting makes the thickness distribution of the fluorescent adhesive layer 4 gradually thinner from the middle to the four peripheral edges.

[0047] When the thickness of the fluorescent adhesive layer 4 in the prior art is consistent, the large-angle light at the four peripheral edges emitted by the light-emitting chip 2 travels a longer distance in the fluorescent adhesive layer 4 than the light in the middle. The large-angle light at the four peripheral edges is likely to excite an excessive amount of phosphor, resulting in yellowing at the edges, etc. In the fluorescent adhesive layer 4 of the present utility model, the thickness gradually thins from the middle to the four peripheral edges, shortening the propagation distance of the large-angle light at the edges and avoiding the large-angle light at the four peripheral edges from exciting an excessive amount of phosphor, making the light output color more uniform.

[0048] The first optical interface 31 can also be set as a micro-curved surface protruding towards the fluorescent adhesive layer 4. Refer to Figure 3 , the thickness distribution of the light-transmitting adhesive layer 3 gradually thins from the middle to the four peripheral edges. When the viscosity of the fluorescent glue is relatively large and the fluidity is poor, on the one hand, the protruding micro-curved surface makes it easier for the fluorescent glue to distribute around; on the other hand, the concentration of phosphor in the middle of the fluorescent adhesive layer 4 is higher than that at the four peripheral edges. By increasing the thickness of the four peripheral edges of the fluorescent adhesive layer 4 to make up for the low concentration of phosphor at the four peripheral edges, the total amount of phosphor in the middle and at the four peripheral edges tends to be consistent, and the light output color consistency is high.

[0049] Furthermore, a high-reflection adhesive layer 5 is provided around the four side surfaces of the light-emitting chip 2, the light-transmitting adhesive layer 3, and the fluorescent adhesive layer 4. Refer to Figure 5 . The reflective adhesive layer 5 is provided on the substrate 1 and tightly covers the side surfaces of the light-emitting chip 2, the light-transmitting adhesive layer 3, and the fluorescent adhesive layer 4, and is used to block and reflect light, so that the light is emitted from the upper surface of the fluorescent adhesive layer 4 to achieve single-sided light output.

[0050] Example 1: Refer to Figure 2 , the light-emitting device includes a substrate 1 and a light-emitting chip 2 provided on the substrate 1. The light-transmitting adhesive layer 3 tightly covers the upper surface of the light-emitting chip 2, and the fluorescent adhesive layer 4 tightly covers the upper surface of the light-transmitting adhesive layer 3. The first optical interface 31 is set as a micro-curved surface recessed into the light-transmitting adhesive layer 3. The thickness of the light-transmitting adhesive layer 3 gradually thickens from the middle to the four peripheral edges. The second optical interface 41 is set as a plane.

[0051] Example 2: Refer to Figure 3 , the main difference from Example 1 is that the first optical interface 31 is set as a micro-curved surface protruding towards the fluorescent glue layer 4. The thickness of the light-transmitting glue layer 3 gradually thins from the middle to the four peripheral edges. Other settings are the same as those in Example 1.

[0052] Example 3: Refer to Figure 4 , the main difference from Example 1 is that the first optical interface 31 includes a flat surface in the middle and inclined flat surfaces or curved surfaces at the four peripheral edges, and the thickness distribution of the light-transmitting glue layer 3 is thin in the middle and gradually thickens towards the four peripheral edges. Other settings are the same as those in Example 1.

[0053] Example 4: Refer to Figure 5 , the main difference from Example 1 is that the first optical interface 31 is set as a flat surface. The four side surfaces of the light-emitting chip 2, the light-transmitting glue layer 3, and the fluorescent glue layer 4 are covered with a high-reflection glue layer 5. Other settings are the same as those in Example 1.

[0054] It is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A light-emitting device, characterized in that, Comprising: A substrate (1); A light-emitting chip (2), which is disposed on the substrate (1); A light-transmitting glue layer (3), which at least covers the upper surface of the light-emitting chip (2); A fluorescent glue layer (4), which at least covers the upper surface of the light-transmitting glue layer (3); Wherein, the light-transmitting glue layer (3) is used to compensate for the thickness difference of the light-emitting chip (2), so that the thickness of the batch-formed fluorescent glue layer (4) is consistent.

2. The light-emitting device according to claim 1, characterized in that The light-transmitting glue layer (3) includes light-diffusing particles.

3. The light-emitting device according to claim 1, characterized in that, The light-transmitting glue layer (3) is provided with a first optical interface (31) on the side close to the fluorescent glue layer (4), and the first optical interface (31) is set as a plane or / and a curved surface.

4. The light-emitting device according to claim 3, characterized in that, The first optical interface (31) is set as a micro-curved surface recessed into the light-transmitting glue layer (3), and the thickness distribution of the light-transmitting glue layer (3) gradually thickens from the middle to the four peripheral edges.

5. The light-emitting device according to claim 3, characterized in that, The first optical interface (31) is set as a micro-curved surface protruding towards the fluorescent glue layer (4), and the thickness distribution of the light-transmitting glue layer (3) gradually thins from the middle to the four peripheral edges.

6. The light-emitting device according to claim 3, wherein, The first optical interface (31) includes a plane in the middle and inclined planes or curved surfaces at the four peripheral edges, and the thickness distribution of the light-transmitting glue layer (3) is thin in the middle and gradually thickens at the four peripheral edges.

7. The light-emitting device according to claim 1, characterized in that, A second optical interface (41) for outputting light is provided on the side of the fluorescent glue layer (4) away from the light-transmitting glue layer (3); the second optical interface (41) is set as a plane or / and a curved surface.

8. The light-emitting device according to claim 1, characterized in that, The thickness of the light-transmitting glue layer (3) is set to 20 - 60 um.

9. The light-emitting device according to claim 1, wherein A high-reflection glue layer (5) is provided around the peripheries of the light-emitting chip (2), the light-transmitting glue layer (3) and the fluorescent glue layer (4).

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