TWI677114B - Light emitting device with beveled reflector - Google Patents

Abstract

The invention provides a light emitting device, which includes an LED chip, a fluorescent structure and a reflective structure. The fluorescent structure is arranged on the LED chip, the side of the fluorescent structure is inclined, and the bottom surface of the fluorescent structure is located on the upper surface of the LED chip; the reflective structure covers the side of the LED chip and the side of the fluorescent structure and presents an inclined guide angle. The present invention further provides a manufacturing method, which can manufacture the above-mentioned light emitting device. Thereby, the light-emitting device with a reflection structure with a guide angle can increase the light-emitting efficiency, change the light-emitting angle, improve the uniformity of spatial light, and achieve a small divergence angle with a small package size.

Description

Light emitting device with guiding angle reflection structure

The invention relates to a light-emitting device and a method for manufacturing the same, and more particularly, to a light-emitting device having an LED chip and a method for manufacturing the same.

LED (Light Emitting Diode) chips are commonly used to provide light sources for illumination or indication, and LED chips are usually placed in a packaging structure or covered or covered with a fluorescent material to become Luminescent device.

The light-emitting device can obtain good light-emitting efficiency and specific light-emitting angle through appropriate design schemes. For example, the traditional PLCC LED package with high economic efficiency, the light-emitting efficiency can be increased through the design of the reflection cup to achieve a specific Luminous angle, but the stent-type LED package has its inherent limitations, such as: the difference in the path of light in the fluorescent glue results in poor spatial light uniformity and yellow halo, and the light output area is much larger than the LED chip area, resulting in a specific direction unit Low area light intensity (intensity) and large light output area make it difficult to design the secondary optical lens, and large thermal resistance makes it difficult to dissipate heat. Therefore, the use of LED flip chips for chip scale packaging to make small-sized light-emitting devices and approaching an ideal point light source can effectively solve the above problems, and small-sized wafer-level packaging can further reduce production costs. Therefore, this trend has become the goal of the industry's efforts. However, as the size of the light-emitting device shrinks, the solution that can be applied to a large-size device becomes difficult to be applied to a small-sized light-emitting device.

In the current small-sized light-emitting device, due to the limitation of the existing process technology, the reflective structure vertically covers the side of the fluorescent structure. This structure causes the light that enters the reflective structure inside the fluorescent material to be limited by the critical angle. Most of it is reflected back into the fluorescent material or LED chip, and it is not easy to be guided to the top surface of the fluorescent structure to be drawn out of the light-emitting device, thus causing more light energy to be lost inside the light-emitting device, so its luminous efficiency can be further improved. Promotion. In addition, at present, there are no effective solutions for adjusting the light emitting angle of small-sized light-emitting devices.

In view of this, a technical solution is provided that can improve the light emitting efficiency of the light emitting device, improve the uniformity of spatial light, reduce the divergence angle, the light emitting area approaches an ideal point light source, reduce thermal resistance, or adjust the light emitting angle. The problem.

An object of the present invention is to provide a light emitting device and a manufacturing method thereof, which can improve the light emitting efficiency and spatial light uniformity of the light emitting device to avoid the occurrence of yellow halo, or adjust the light emitting angle thereof, while having a small light emitting area and low thermal resistance.

Another object of the present invention is to provide a light-emitting device and a manufacturing method thereof, which can make a small-sized light-emitting device have good light-emitting efficiency and / or spatial light uniformity to avoid the occurrence of yellow halo, or adjust its light-emitting angle.

To achieve the above object, a light-emitting device disclosed in the present invention includes an LED chip, a fluorescent structure, and a reflective structure. The LED chip has an upper surface, a lower surface opposite to the upper surface, a side surface, and an electrode group. The side surface is formed between the upper surface and the lower surface, and the electrode group is disposed on the lower surface. The light structure is disposed on the LED chip, and has a top surface, a bottom surface opposite to the top surface, and a side surface formed between the top surface and the bottom surface, wherein the top surface is larger than the bottom surface so that the side faces are opposite to each other. An inclined shape is formed on the top surface and the bottom surface, and the bottom surface is located on the upper surface of the LED chip; the reflective structure covers a side surface of the LED chip and a side surface of the fluorescent structure.

To achieve the above object, a method for manufacturing a light-emitting device disclosed in the present invention includes: forming a fluorescent structure having an inverted tapered side; and placing the fluorescent structure on an LED chip to form a light-emitting structure; And covering the side of the light-emitting structure to form a reflective structure with an inverted tapered inner lead angle.

Therefore, the light-emitting device and the manufacturing method thereof of the present invention can provide at least the following beneficial effects: the reflective structure with a guide angle can make the light of the LED chip be more easily drawn out of the light-emitting device, and can increase the light-emitting efficiency and / or light uniformity. In addition, the fluorescent structure can be slightly larger than the LED chip, so the light-emitting device formed can have a small-sized appearance. On the other hand, in addition to a fluorescent structure having an inclined side surface, in addition to being easily manufactured, the inclination angle of the inclined side surface can also be adjusted to further control the light emission angle.

In order to make the above-mentioned objects, technical features, and advantages more comprehensible, the following describes in detail the preferred embodiments in combination with the accompanying drawings.

1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1I, 1J, 1K‧‧‧light-emitting devices

10‧‧‧LED Chip

11‧‧‧ top surface

12‧‧‧ lower surface

13‧‧‧ side

14‧‧‧electrode set

20‧‧‧Fluorescent structure

20’‧‧‧ transparent structure

201‧‧‧Fluorescent layer

201’‧‧‧ fluorescent layer

202‧‧‧light-transmitting layer

203‧‧‧lens array layer

21‧‧‧Top

22‧‧‧ underside

23‧‧‧side, inclined side

23’‧‧‧ vertical side

30‧‧‧Reflective structure

31‧‧‧ inside

32‧‧‧inner angle, inner bevel

33‧‧‧Top

34‧‧‧ underside

35‧‧‧ outside

40‧‧‧ substrate

50, 50 ’, 50” ‧‧‧ auxiliary materials

60‧‧‧Punching tool

61‧‧‧Blade

70‧‧‧Saw wheel, double angle milling cutter

71‧‧‧Blade

L‧‧‧light

X‧‧‧ upward tilt

T‧‧‧thickness

W‧‧‧ length

H‧‧‧ height

FIG. 1 is a schematic diagram of a light emitting device according to a first preferred embodiment of the present invention.

FIG. 2 is a schematic diagram of a light emitting device according to a second preferred embodiment of the present invention.

FIG. 3 is a schematic diagram of a light emitting device according to a third preferred embodiment of the present invention.

FIG. 4 is a schematic diagram of a light emitting device according to a fourth preferred embodiment of the present invention.

FIG. 5 is a schematic diagram of a light emitting device according to a fifth preferred embodiment of the present invention.

FIG. 6 is a schematic diagram of a light emitting device according to a sixth preferred embodiment of the present invention.

FIG. 7 is a schematic diagram of a light emitting device according to a seventh preferred embodiment of the present invention.

FIG. 8 is a schematic diagram of a light emitting device according to an eighth preferred embodiment of the present invention.

FIG. 9 is a schematic diagram of a light emitting device according to a ninth preferred embodiment of the present invention.

FIG. 10 is a schematic diagram of a light emitting device according to a tenth preferred embodiment of the present invention.

11A to 11D are schematic diagrams of steps for forming a fluorescent film according to a method for manufacturing a light emitting device according to a preferred embodiment of the present invention.

FIG. 12A to FIG. 12C are schematic diagrams of steps for forming another fluorescent film according to a method for manufacturing a light emitting device according to a preferred embodiment of the present invention.

13A and 13B are schematic diagrams and comparison diagrams of light transmission in a light emitting device (the fluorescent layer of the fluorescent structure is not shown).

FIG. 14 and FIG. 15 are schematic diagrams of steps for forming another fluorescent film according to a method for manufacturing a light emitting device according to a preferred embodiment of the present invention.

FIG. 16A to FIG. 16F are schematic diagrams of steps of die-cutting a fluorescent film according to a method for manufacturing a light emitting device according to a preferred embodiment of the present invention.

FIG. 17 is a schematic diagram of a step of cutting a fluorescent film according to a manufacturing method of a light emitting device according to a preferred embodiment of the present invention.

18A and 18B are schematic diagrams of steps for forming a light emitting structure in a method for manufacturing a light emitting device according to a preferred embodiment of the present invention.

FIG. 19 is a schematic diagram of steps for forming a reflective structure in a method for manufacturing a light emitting device according to a preferred embodiment of the present invention.

FIG. 20 is a schematic diagram of steps for removing auxiliary materials in a method for manufacturing a light emitting device according to a preferred embodiment of the present invention.

FIG. 21 is a schematic diagram of a step of cutting a reflective structure in a method for manufacturing a light emitting device according to a preferred embodiment of the present invention.

22A to 22B, 22D, and 22E are the 11th preferred embodiment according to the present invention. 22D and 22E are schematic diagrams of light transmission in the light-emitting device, and FIG. 22C is a schematic diagram of light transmission when the light-emitting device has a uniformly distributed fluorescent material.

Please refer to FIG. 1, which is a schematic diagram of a light emitting device according to a first preferred embodiment of the present invention. The light-emitting device 1A may include an LED chip 10, a fluorescent structure 20, and a reflective structure 30, and the technical content of these components will be described in order as follows.

The LED chip 10 may be a flip-chip type wafer, and may have an upper surface 11, a lower surface 12, a side surface 13, and an electrode group 14 in appearance. The upper surface 11 and the lower surface 12 are opposite to each other, and the side surface 13 is formed between the upper surface 11 and the lower surface 12 and connects the upper surface 11 and the lower surface 12. The electrode group 14 is disposed on the lower surface 12 and may have more than two electrodes. Electric energy (not shown) can be supplied into the LED chip 10 through the electrode group 14, and then the LED chip 10 emits light. Most of the light emitted by the LED chip 10 exits from the upper surface 11.

The fluorescent structure 20 can change the wavelength of the light emitted by the LED chip 10, and can have a top surface 21, a bottom surface 22, and a side surface 23 on the appearance; the top surface 21 and the bottom surface 22 are opposite and oppositely disposed, and the side surface 23 is formed Between the top surface 21 and the bottom surface 22 and connecting the top surface 21 and the bottom surface 22. The top surface 21 and the bottom surface 22 can be horizontal planes, so they can be parallel.

The top surface 21 is larger than the bottom surface 22, that is, the area of the top surface 21 is larger than the area of the bottom surface 22, so when viewed downward in the normal direction, the top surface 21 can cover the bottom surface 22. When the top surface 21 is larger than the bottom surface 22, the side surface 23 will be inclined relative to the top surface 21 and the bottom surface 22. Therefore, the side surface 23 may also be referred to as an inclined side surface 23. The inclined side surface 23 is formed along the contours of the top surface 21 and the bottom surface 22. Therefore, the inclined side surface 23 is annular with respect to the top surface 21 and the bottom surface 22. Therefore, the fluorescent structure 20 appears as a frustum in appearance, and the side surface 23 is an inverted cone-shaped side surface.

The fluorescent structure 20 may include a fluorescent layer 201 and at least one light-transmitting layer 202 on the structure, and at least one light-transmitting layer 202 is formed on the fluorescent layer 201, or it may be said that the light-transmitting layer 202 is stacked on the fluorescent layer 201 on. Both the light-transmitting layer 202 and the fluorescent layer 201 allow light to pass through, so their manufacturing materials can include a light-transmitting material such as a light-transmissive resin, while the material of the fluorescent layer 201 further includes a fluorescent powder, which is mixed in Light-transmitting materials. When the light from the LED chip 10 passes through the fluorescent layer 201, the wavelength of part of the light will change, and then it continues to pass through the light-transmitting layer 202.

Although the light transmitting layer 202 does not change the wavelength of light, it can protect the fluorescent layer 201 so that substances in the environment cannot easily contact the fluorescent layer 201. In addition, the light-transmitting layer 202 can also increase the overall structural strength of the fluorescent structure 20, so that the fluorescent structure 20 is not easily bent, and provides sufficient operability in production.

The fluorescent structure 20 is located on the LED chip 10 in position, and the bottom surface 22 of the fluorescent structure 20 is located on the upper surface 11 of the LED chip 10, so the top surface 21 and the inclined side surface 23 are also located on the upper surface 11 of the LED chip 10. . In other words, the entire fluorescent structure 20 is located on the upper surface 11 of the LED chip 10.

Preferably, the bottom surface 22 of the fluorescent structure 20 can be adhered to the upper surface 11 of the LED chip 10 through an adhesive material (not shown) such as an adhesive (such as silicone) or tape, so that the fluorescent structure 20 and the The fixing between the LED chips 10 is better. In addition, the bottom surface 22 of the fluorescent structure 20 may not be less than (ie, greater than or equal to) the upper surface 11 of the LED chip 10, so when viewed downward along the normal direction, the fluorescent structure 20 may shield the LED chip 10.

The reflective structure 30 covers the side surface 13 of the LED chip 10 and the inclined side surface 23 of the fluorescent structure 20, but does not cover the top surface 21 of the fluorescent structure 20. In this embodiment, the inclined side surface 23 of the fluorescent structure 20 is completely Wrapped. The reflective structure 30 can block the light from the LED chip 10, so the light is reflected at the side surface 13 and the inclined side surface 23, and is finally guided to the top surface 21.

Preferably, when the reflection structure 30 covers the side surface 13 and the inclined side surface 23, the side surface 13 and the inclined side surface 23 are adhered to each other, so that there is no gap between the reflection structure 30 and the side surface 13 and the inclined side surface 23. Therefore, the reflective structure 30 has an inner side surface 31 which is in contact with the side surface 13 and an inner leading angle (or inner inclined surface) 32 which is in contact with the inclined side surface 23. Since the inclined side surface 23 is an inverted cone side surface, The corresponding inner lead angle 32 is an inverted cone-shaped inner side surface, so that the reflection structure 30 presents an inner lead angle reflection surface. In addition, a top surface 33 of the reflective structure 30 may be flush with the top surface 21 of the fluorescent structure 20; the reflective structure 30 also has an outer side surface 35 which is separated from the inner side surface 31 and the inner inclined surface 32, and the outer side surface 35 may be Is a vertical plane.

In the manufacturing material, the reflective structure 30 may be made of a material including a reflective resin, and the reflective resin may be, for example, polyphthalamide (PPA), polycyclohexane terephthalate Methyl Ester (Polycyclolexylene-di-methylene Terephthalate (PCT) or Epoxy molding compound (EMC)).

The reflective structure 30 may also be made of another material including a light-transmitting resin, and the light-transmitting resin includes reflective particles. The light-transmissive resin may be, for example, silicone or low reflection coefficient silicon (the refractive index may be about 1.35 to 1.45), and the reflective particles may be titanium dioxide (TiO ₂ ), boron nitride (BN), or silicon dioxide (SiO ₂ ). Or aluminum oxide (Al ₂ O ₃ ); the size of the reflective particles can be set to about 0.5 times the visible light wavelength. In addition to the above-mentioned manufacturing materials, the reflective structure 30 may also be made of other materials.

The above is the technical content of each element of the light emitting device 1A, and the light emitting device 1A has at least the following technical characteristics.

As shown in FIG. 13A, the fluorescent structure 20 has an inclined side surface 23, so that the light L of the LED chip 10 or the light emitted through the fluorescent layer 201 (as shown in FIG. 1) can be transmitted along the inclined side surface 23. In other words, the fluorescent structure 20 is emitted more efficiently; in other words, the inclined side surface 23 is beneficial for guiding the light L out of the top surface 21 of the fluorescent structure 20, and it is not easy to cause the light L to be reflected back into the fluorescent structure 20 or the LED chip 10, This reduces the loss of light energy. Therefore, the light L emitted from the LED chip 10 can be well extracted out of the fluorescent structure 20, so that the light-emitting device 1A has a good light-emitting efficiency as a whole. Compared with the fluorescent structure 20 without the inclined side (as shown in FIG. 13B, the light L is easily reflected by the top surface 21 back to the fluorescent structure 20 or the LED chip 10 due to the limit of the critical angle), The improvement of the luminous efficiency of the fluorescent structure 20 with the inclined side surface 23 will be easier to understand.

In addition, while the inclined side surface 23 of the fluorescent structure 20 improves the light extraction efficiency, the light emitting device 1A can also have good spatial light uniformity and can avoid the occurrence of yellow halo. Furthermore, when the inclined side surfaces 23 have different inclination angles, the light emitting device 1A will have different light emission angles. Therefore, the purpose of adjusting the light emission angle can be achieved by designing the inclination angle.

In addition to increasing the luminous efficiency of the fluorescent structure 20 by tilting the side surface 23, the luminous efficiency can also be increased by adjusting the refractive index of the light-transmitting layer 202 to be smaller than the refractive index of the fluorescent layer 201. That is, the refractive index of the light-transmitting layer 202 can be between the fluorescent layer 201 and air, so that when the light of the LED chip 10 enters the air through the light-transmitting layer 202, the interface can be reduced due to the difference in refractive index reflection.

If there are two or more light-transmitting layers 202 (not shown), the refractive indexes of the light-transmitting layers 202 may be different (that is, the manufacturing materials of the two light-transmitting layers 202 are different), and the refractive index of the upper ones is less than The refractive index of the lower one. In this way, the luminous efficiency can be further improved.

On the other hand, the fluorescent structure 20 can be only a little larger than the LED chip 10. Therefore, when the LED chip 10 is small, the fluorescent structure 20 can also be set to a small size; and the reflective structure 30 for covering can also be set to a small size. The size is such that the size of the final light emitting device 1A is small. In other words, if the size of the light-emitting device 1A needs to be designed to be small or chip scale, the use of the fluorescent structure 20 is also feasible, and the light-emitting efficiency can be increased. In an example, the width and length of the light-emitting device 1A correspond to the length and width of the reflective structure 30, and the width is not greater than 2.0 mm, and the length is not greater than 3.0 mm.

The above is a description of the technical content of the light-emitting device 1A. Next, the technical content of the light-emitting device according to other embodiments of the present invention will be described. The technical content of the light-emitting device of each embodiment should be referred to each other, so the same parts will be omitted or simplified. .

Please refer to FIG. 2, which is a schematic diagram of a light emitting device according to a second preferred embodiment of the present invention. The light-emitting device 1B differs from other light-emitting devices in that at least the light-transmitting layer 202 is formed under the fluorescent layer 201 in the fluorescent structure 20 of the light-emitting device 1B. That is, the light-transmitting layer 202 is located between the fluorescent layer 201 and the upper surface 11 of the LED chip 10, so the fluorescent layer 201 does not contact the LED chip 10. Therefore, the thermal energy generated during the operation of the LED chip 10 is less likely to affect the fluorescent layer 201, that is, the temperature of the fluorescent layer 201 is less likely to rise due to the thermal energy. Therefore, the fluorescent layer 201 is effective in converting the wavelength of light. , Not easy to decay. In addition, the refractive index of the fluorescent layer 201 may be smaller than the refractive index of the light-transmitting layer 202 to increase the luminous efficiency.

Please refer to FIG. 3, which is a schematic diagram of a light emitting device according to a third preferred embodiment of the present invention. The light-emitting device 1C differs from other light-emitting devices at least in that the fluorescent structure 20 of the light-emitting device 1C further includes a lens array layer 203 formed on the fluorescent layer 201. The lens array layer 203 can be integrally formed with the light transmission layer 202, so the light transmission layer 202 can be regarded as a part of the lens array layer 203; the lens array layer 203 can be higher than the top surface 33 of the reflective structure 30, so that the top surface of the fluorescent structure 20 21 is higher than the top surface 33 of the reflective structure 30. The lens array layer 203 can further increase the light emitting efficiency of the light emitting device 1C.

Please refer to FIG. 4, which is a schematic diagram of a light emitting device according to a fourth preferred embodiment of the present invention. The light-emitting device 1D differs from other light-emitting devices at least in that the fluorescent structure 20 of the light-emitting device 1D includes a plurality of light-transmitting layers 202, and the fluorescent layer 201 is formed between the light-transmitting layers 202. In such a configuration, the light-transmitting layer 202 can protect the fluorescent layer 201 and reduce the influence of the thermal energy of the LED chip 10 on the fluorescent layer 201. In addition, the refractive index of the fluorescent layer 201 may be less than The refractive index of the transparent layer 202 located below is larger than the refractive index of the transparent layer 202 located above to increase the luminous efficiency.

Please refer to FIG. 5, which is a schematic diagram of a light emitting device according to a fifth preferred embodiment of the present invention. The light-emitting device 1E differs from other light-emitting devices at least in that the fluorescent structure 20 of the light-emitting device 1E is a single-layer fluorescent structure, that is, it includes only the fluorescent layer 201 and no light-transmitting layer. Therefore, the thickness of the fluorescent layer 201 can be large, and a larger proportion of light can be converted into wavelengths, which is suitable for LED light-emitting devices that need to convert a large amount of light wavelengths, such as white LEDs with low color temperature.

Please refer to FIG. 6, which is a schematic diagram of a light emitting device according to a sixth preferred embodiment of the present invention. The light-emitting device 1F differs from other light-emitting devices at least in that the light-emitting device 1F further includes a substrate 40, and the LED chip 10 and the reflective structure 30 are both disposed on the substrate 40. The electrode group 14 of the LED chip 10 is further electrically connected to the substrate. 40. The substrate 40 is an element capable of transmitting electric energy (for example, a circuit board, a bracket, etc.), so the electric energy can be supplied to the light-emitting device 1F through the substrate 40. The reflective structure 30 may further extend between the lower surface 12 of the LED chip 10 and the substrate 40.

Please refer to FIG. 7, which is a schematic diagram of a light emitting device according to a seventh preferred embodiment of the present invention. The light-emitting device 1G differs from other light-emitting devices in that the top surface 21 of the fluorescent structure 20 of the light-emitting device 1G is higher than the top surface 33 of the reflective structure 30, and the inclined side surface 23 of the fluorescent structure 20 is partially exposed on the reflective structure 30. . In other words, the reflective structure 30 only partially covers the inclined side surface 23 of the fluorescent structure 20. Since the top surface 33 of the reflective structure 30 is lower than the top surface 21 of the fluorescent structure 20, the reflective structure 30 will not spread to the top surface 21 of the fluorescent structure 20 when it is formed, so the tolerance of the process error is increased, which can be effective The yield and productivity are improved, so the production cost can be further reduced without resorting to a mold (for details, refer to the manufacturing method in the embodiment described later).

Please refer to FIG. 8, which is a schematic diagram of a light emitting device according to an eighth preferred embodiment of the present invention. The light-emitting device 1H differs from other light-emitting devices at least in that although the reflective structure 30 of the light-emitting device 1H completely covers the inclined side surface 23 of the fluorescent structure 20, the top surface 33 of the reflective structure 30 is not a flat surface, but is guided from the inside. The angle 32 gradually slopes downward; in other words, the top surface 33 of the reflective structure 30 is recessed downward from the top surface 21 of the fluorescent structure 20. When this type of reflective structure 30 is formed, the tolerance of the process error can also be increased.

Please refer to FIG. 9, which is a schematic diagram of a light emitting device according to a ninth preferred embodiment of the present invention. The light-emitting device 1I differs from other light-emitting devices in that at least the light-emitting device The top surface 21 of the fluorescent structure 20 disposed at 1I may shield the reflective structure 30 in the normal direction; that is, when looking down in the normal direction, only the fluorescent structure 20 is observed, but no reflection is observed. Structure 30. As such, the width and length of the reflective structure 30 will be further reduced, so that the light emitting device 1I can have a smaller size.

Please refer to FIG. 10, which is a schematic diagram of a light emitting device according to a tenth preferred embodiment of the present invention. The light-emitting device 1J differs from other light-emitting devices in that at least the fluorescent structure 20 of the light-emitting device 1J can tilt the bottom surface 34 of the reflective structure 30 upward. Specifically, when the reflective structure 30 is formed, it is solidified from a liquid manufacturing material at a relatively high temperature, and the curing process will cause the volume of the reflective structure 30 to shrink, and the cooling process will also cause the reflective structure 30 and fluorescent The volume of the light structure 20 is reduced. Since the fluorescent structure 20 and the reflective structure 30 are attached to each other, when the volume of the fluorescent structure 20 and the reflective structure 30 is reduced, the bottom surface 34 of the reflective structure 30 will tilt upward due to deformation.

The amount of upward tilt X of the bottom surface 34 is related to factors such as material characteristics and size differences between the fluorescent structure 20 and the reflective structure 30, so adjusting these factors can obtain the required amount of upward tilt X. Preferably, the upward tilt amount X is at least 3 micrometers.

The upward tilt of the bottom surface 34 can provide the following beneficial effects: During the process of bonding the light emitting device 1J to a substrate (not shown), thermal energy is often applied to the light emitting device 1J and the substrate (such as in the case of a reflow process or eutectic bonding). (The thermal energy must be applied at the same time), and the thermal energy will cause the reflective structure 30 and the fluorescent structure 20 to expand; if it is not tilted upward, the bottom surface 34 of the expanded reflective structure 30 may push the substrate, and then cause the light-emitting device 1J to be lifted, and then Causes bonding failure; however, the bottom surface 34 of the reflective structure 30 of the light-emitting device 1J of this embodiment does not push the substrate, because the bottom surface 34 is inclined upward.

In the light-emitting devices 1A-1J in the above embodiments, the technical contents of the light-emitting devices 1A-1J should be applicable to each other, and are not limited to the embodiments themselves. For example, the lens array layer 203 of the light-emitting device 1C, the substrate 40 of the light-emitting device 1F, and the upwardly inclined bottom surface 34 of the light-emitting device 1J can be applied to light-emitting devices of other embodiments (not shown). In addition, in the light-emitting device 1A-1J, the fluorescent structure 20 can be increased by a plurality of fluorescent layers 201 and light-transmitting layers 202 according to design requirements, and the stacking order can be appropriately adjusted, or the fluorescent structure 20 can be appropriately adjusted. Adding a filler such as titanium dioxide (TiO ₂ ) to achieve the best overall effect.

Furthermore, the technical contents of the light-emitting devices 1A-1J can also be applied to the production of monochromatic LEDs 1K that emit monochromatic light. As shown in FIG. 22A, the light-emitting devices 1K The fluorescent structure 20 of the foregoing embodiment is replaced with a transparent structure 20 'made of a transparent material, that is, the transparent structure 20' does not include a fluorescent layer or a fluorescent material, and thus the wavelength of light emitted by the LED chip 10 has a wavelength. It is not converted when passing through the transparent structure 20 '. In this way, it can be used to make small-size light-emitting devices such as red light, green light, blue light, infrared light, or ultraviolet light. It also has a small divergence angle and a small light output area to facilitate the design of secondary lenses, small thermal resistance, and Adjustable lighting angle and other benefits.

And because some applications require a highly directional light source, it is necessary to further reduce the divergence angle. As shown in FIG. 22B, when the side surface inclination angle of the transparent structure 20 'is zero (i.e., becomes the vertical side surface 23'), a smaller divergence angle can be obtained. This divergence angle can be further reduced by increasing the height H of the reflective structure 30. Preferably, the height H of the reflective structure 30 is not less than 0.1 times the length W of the LED chip 10 and not more than 5 times the length W of the LED chip 10 (that is, the aspect ratio is 0.1 ≦ H / W ≦ 5). Although the transparent structure 20 'on the vertical side 23' will sacrifice the overall light output efficiency, the reduced divergence angle can make the light energy more concentrated, resulting in an increase in the luminous flux per unit area (i.e., illuminance) in a specific direction, which is consistent with a highly directional light source Applications. Preferably, the transparent structure 20 'is made of a transparent material with a low refractive index. The closer the refractive index is to 1, the better the effect of increasing the illuminance.

In addition, if a fluorescent layer 201 '(as shown in FIG. 22D) is disposed on the bottom of the transparent structure 20', it can further meet the application of a highly directional white light source. For example, as shown in FIG. 22C, when the fluorescent material of the light emitting device is uniformly distributed in the transparent structure 20 ', the light L will scatter when it encounters the fluorescent material, and the directivity of light cannot be improved by the reflective structure 30. Therefore, arranging the fluorescent layer 201 'on the bottom of the transparent structure 20' (and stackable on the LED chip 10) can prevent light L from being scattered in the transparent structure 20 '. For example, as shown in FIG. 22D, under the condition that there is no scattering in the transparent structure 20 ', light L with a large incident angle (the angle between the vertical direction) will be reflected by the reflection structure 30 multiple times, causing its light intensity to rapidly decay. It is not easy to leave the transparent structure 20 '(because light L is easily reflected on the top surface of the transparent structure 20' and returns to the transparent structure 20 '); as shown in FIG. 22E, the small incident angle (the angle between the vertical direction and the small one) is small. The light L is rarely reflected by the reflective structure 30 and easily leaves the transparent structure 20 '. In this way, the light emitting device 1K can filter out most of the light L having a large incident angle, so that the light L emitted as a whole has a smaller divergence angle and higher directivity.

The above-mentioned light-emitting device 1K may also be a wafer-level packaged light-emitting device, that is, the transparent structure 20 'is equal to or slightly larger than the LED chip 10 in length and width, and the reflective structure 30 is slightly larger 于 LED 片 10。 LED chip 10. In this way, the light-emitting device 1K can improve the lack of the currently-known light-emitting device that cannot meet the wafer-level package with a small divergence angle.

Next, a method for manufacturing a light-emitting device according to a preferred embodiment of the present invention will be described. This manufacturing method can produce the same or similar light-emitting devices 1A-1J as the above-mentioned embodiments. Therefore, the technical content of the manufacturing method and the light-emitting devices 1A-1J The technical content can be referred to each other. The manufacturing method may include three stages: forming a fluorescent structure having an inverted tapered side; setting the fluorescent structure on an LED wafer to form a light emitting structure; and covering the side of the light emitting structure to form A reflective structure with an inverted tapered inner lead. The technical content of each phase is explained in order as follows.

The formation of the fluorescent structure 20 can be divided into indirect formation or direct formation. Indirect formation refers to: forming a fluorescent film first, and then dividing the fluorescent film into a plurality of fluorescent structures. Please refer to FIG. 11A to FIG. 11D, which are schematic diagrams of the steps of “forming a fluorescent film”. As shown in FIG. 11A, an auxiliary material (such as a release film) 50 is first provided, and the auxiliary material 50 can also be placed on a supporting structure (such as a silicon substrate or a glass substrate, not shown).

As shown in FIG. 11B, the fluorescent layer 201 is then formed on the auxiliary material 50, which can be achieved by processes such as spray coating, printing, or molding, that is, fluorescent The manufacturing material of the layer 201 is set on the auxiliary material 50 through these processes, and the fluorescent layer 201 can be formed after the manufacturing material is cured. The method for forming a fluorescent layer disclosed in US Patent Application Publication Nos. US2010 / 0119839 and US2010 / 0123386 can also be applied in this embodiment, which can well control the thickness and uniformity of the fluorescent layer; the two US patents The technical content of the application is incorporated herein by reference in its entirety.

As shown in FIG. 11C, the light-transmitting layer 202 is then formed on the fluorescent layer 201, which can be achieved by processes such as spraying, printing, molding, or dispensing. If two or more light-transmitting layers 202 need to be formed, a spraying process is more suitable. As shown in FIG. 11D, after the transparent layer 202 is formed, the auxiliary material 50 may be removed to obtain a fluorescent film 200 composed of the transparent layer 202 and the fluorescent layer 201. The fluorescent film 200 may correspond to the fluorescent structure 20 of the light emitting device 1A (as shown in FIG. 1), or may correspond to the fluorescent structure 20 of the light emitting devices 1G, 1H, and 1J (as shown in FIGS. 7, 8, and 10) By inverting the manufactured fluorescent film 200 upside down when cutting, it can correspond to the fluorescent structure 20 of the light emitting device 1B (as shown in FIG. 2).

By changing the formation order of the light transmitting layer 202 and the fluorescent layer 201, different fluorescent films 200 can be obtained. For example, as shown in FIGS. 12A to 12C, the light transmitting layer 202 and the fluorescent layer 201 and another transparent layer 202 are sequentially formed on the auxiliary material 50 to form a fluorescent film 200 corresponding to the fluorescent structure 20 (as shown in FIG. 4) of the light emitting device 1D. As shown in FIG. 14, only the fluorescent layer 201 is formed on the auxiliary material 50, so a fluorescent structure 20 (as shown in FIGS. 5, 6, and 9) corresponding to the light emitting devices 1E, 1F, and 1I can be formed. Fluorescent film 200.

As shown in FIG. 15, after the fluorescent layer 201 is formed, a lens array layer 203 can be formed on the fluorescent layer 201. The lens array layer 203 can be formed by molding, that is, the fluorescent layer 201 and the auxiliary material 50 are placed in a mold (not shown), and then the manufacturing material of the lens array layer 203 is injected into the mold to manufacture the material. The curing may form the lens array layer 203. Such a fluorescent film 200 composed of the fluorescent layer 201 and the lens array layer 203 may correspond to the fluorescent structure 20 of the light emitting device 1C (as shown in FIG. 3).

After the various fluorescent films 200 are formed, the fluorescent film 200 may be divided into a plurality of portions having an inclined side surface by punching, and one of the portions is the fluorescent structure 20.

Specifically, referring to FIG. 16A and FIG. 16B, the fluorescent film 200 is first turned over and placed on another auxiliary material 50 'with the bottom surface facing upward, and then a punching cutter 60 punches from above. Fluorescent film 200. Please refer to FIG. 16C, the punching cutter 60 has a plurality of blades 61, and the blades 61 are connected and arranged according to the shape of the fluorescent structure 20, for example, arranged in a rectangular shape. Therefore, when the punching blade 60 punches the fluorescent film 200, as shown in FIG. 16D and FIG. 16E, the fluorescent film 200 will be divided into a plurality of fluorescent structures 20; that is, a plurality of fluorescent structures may be formed by one punching. 20 fluorescent structure 20. The bottom surface 22 of the fluorescent structures 20 is a cutting edge 61 facing the cutting tool 60. In addition, as shown in FIG. 16F, when the die-cut fluorescent film 200 includes the lens array layer 203, the lens array layer 203 is placed on the auxiliary material 50 '.

It can be seen that the punching method can quickly divide the fluorescent film 200 into a plurality of fluorescent structures 20. In addition, the inclination angle of the inclined side surface 23 of the fluorescent structure 20 can also be controlled by several factors, such as adjusting the angle (or section) of the blade 61, the geometric size of the fluorescent structure 20, and / or the material properties of the fluorescent film 200 And other factors. Therefore, when these factors are set in advance, the desired inclined side surface 23 can be obtained.

In addition to die cutting, sawing, precision machining, or micro machining can be used to form the fluorescent film 200 into a plurality of fluorescent structures 20. Refer to Figure 17, a saw wheel or dual angle milling cutter cutter) 70 multiple times to cut the fluorescent film 200 so that the fluorescent film 200 is divided into a plurality of fluorescent structures 20; the bottom surface 22 of the fluorescent structures 20 is the blade 71 facing the saw wheel or the double-angle milling cutter 70. The inclination angle of the inclined side surface 23 of the fluorescent structure 20 can be controlled by the angle (or cross section) of the blade 71. In the microfabrication method, steps such as barrier layer deposition, shape definition, and etching can be used to form the fluorescent structure 20.

The above-mentioned method is to form the fluorescent structure 20 indirectly from the fluorescent film 200. If the fluorescent structure 20 is directly formed by molding, micro machining, or the like. Specifically, in the molding method, a mold (not shown) will be provided, and the shape of the cavity will correspond to the appearance of the fluorescent structure 20, and then the manufacturing material of the fluorescent structure 20 will be injected into the cavity to manufacture the material. After curing, the fluorescent structure 20 can be formed. In the micro-machining method, the fluorescent structure 20 is formed by steps such as coating, exposure, development, and / or etching. The moulding and microfabrication methods can also be used to produce a plurality of fluorescent structures 20 in batch production.

In addition to soft light-transmitting materials such as light-transmissive resins, brittle light-transmitting materials such as glass and ceramics can also be used to form the fluorescent structure 20 according to application requirements. Among them, in the indirect method, a method such as sintering can be used to form a fluorescent sheet first, and then a plurality of fluorescent structures 20 can be formed using sawing or the like; in the direct method, fluorescent materials and light-transmitting material powder It is placed in the cavity and sintered to directly form a plurality of fluorescent structures 20; and the manufacturing method of the fluorescent structure 20 can also be applied to the transparent structure 20 '. In addition, a plurality of transparent structures 20 'may be formed by directly passing a transparent glass substrate or a transparent ceramic substrate through a method such as sawing.

Next, "the formation of a light emitting structure" will be described. Please refer to FIG. 18A. First, a plurality of LED chips 10 are placed on another auxiliary material 50 "at intervals. The auxiliary material 50" may be a UV release tape or a thermal release tape. Wait. In addition, the LED chip 10 can be pressed so that its electrode group 14 is embedded in the auxiliary material 50 ”without being exposed. If a substrate 40 is provided below the LED chip 10 (as shown in FIG. 6), the auxiliary is not required材 50 ".

Referring to FIG. 18B, the fluorescent structure 20 is placed on the upper surface 11 of the LED chip 10, and the inclined side surface 23 of the fluorescent structure 20 is exposed outside the upper surface 11. The fluorescent structure 20 can be passed through adhesive or tape. Adhesive to the upper surface 11 of the LED chip 10. In this way, the fluorescent structure 20 and the LED chip 10 can form a light emitting structure.

Next, "the formation of a reflective structure" will be described. The reflection structure 30 is formed by covering the side surface 13 of the LED chip 10 and the inclined side surface 23 of the fluorescent structure 20 together (that is, simultaneously). The specific methods are at least two kinds of molding and dispensing. Please refer to FIG. 19, when the molding is adopted, the fluorescent structure 20, the LED chip 10, and the auxiliary material 50 "will be placed in a mold (not shown), and then the manufacturing material of the reflective structure 30 is injected into the mold. And cover the side surface 13 of the LED chip 10 and the inclined side surface 23 of the fluorescent structure 20; after the manufacturing material is cured, the reflection structure 30 can be formed. The reflection structure 30 under this method can cover all the inclined side surfaces 23.

When dispensing, the above-mentioned mold is not needed. The manufacturing material of the reflective structure 30 will be directly poured onto the auxiliary material 50 ", and then the manufacturing material will gradually thicken on the auxiliary material 50" to cover the side 13 of the LED chip 10 and the inclined side 23 of the fluorescent structure 20, The pouring manufacturing material does not exceed the top surface 21 of the fluorescent structure 20. When the poured manufacturing material is slightly reduced, the reflective structure 30 formed by curing it will be as shown in FIGS. 7 and 8.

After the reflective structure 30 is formed, as shown in FIG. 20, the auxiliary material 50 "will be removed to obtain a plurality of light-emitting devices 1A (or other types of light-emitting devices). The reflective structures 30 of these light-emitting devices 1A may They are connected to each other, so a cutting step (as shown in FIG. 21) may be taken to cut and separate the connected reflective structures 30 to the separated light-emitting device 1A.

To sum up, the manufacturing method of the light-emitting device in this embodiment can manufacture various light-emitting devices having a fluorescent structure with inclined sides, and the light-emitting device may be a small-sized one. In addition, the manufacturing method has the characteristics that a large number of fluorescent structures can be produced in batches, and the reflective structure can be formed without a mold to reduce costs and the like.

The above embodiments are only used to exemplify the implementation aspects of the present invention, and to explain the technical features of the present invention, and are not intended to limit the protection scope of the present invention. Any change or equivalence arrangement that can be easily accomplished by those skilled in the art belongs to the scope claimed by the present invention, and the scope of protection of the rights of the present invention shall be subject to the scope of patent application.

Claims (16)

A light-emitting device includes an LED chip having an upper surface, a lower surface opposite to the upper surface, a side surface, and an electrode group. The side surface is formed between the upper surface and the lower surface. The electrode group is disposed on On the lower surface; a fluorescent structure is disposed on the LED chip and has a top surface, a bottom surface opposite to the top surface, and a side surface formed between the top surface and the bottom surface, wherein the top surface Larger than the bottom surface, the side surface is inclined with respect to the top surface and the bottom surface, the bottom surface is located on the upper surface of the LED chip, and the fluorescent structure includes a fluorescent layer and a light transmitting layer. A light layer is formed on the fluorescent layer; and a reflective structure covers the side of the LED chip and the side of the fluorescent structure, and an outer edge of a top surface of the reflective structure is lower than that of the fluorescent structure. Top surface, but above one of the phosphor layers. The light-emitting device according to claim 1, wherein the bottom surface of the fluorescent structure is adhered to the upper surface of the LED chip, and the bottom surface of the fluorescent structure is not less than the upper surface of the LED chip. The light-emitting device according to claim 1, wherein the reflective structure is made of one material including a reflective resin, or made of another material including a light-transmitting resin, and the light-transmitting resin Contains reflective particles. The light-emitting device according to claim 3, wherein the reflective resin is polyphthalamide, polycyclohexane dimethanol terephthalate, or epoxy resin; the light-transmissive resin is silicone; the The reflective particles are titanium dioxide, boron nitride, silicon dioxide, or aluminum oxide. The light-emitting device according to claim 3, wherein the light-transmissive resin is a low-reflectivity silicone gel and contains reflective particles. The light-emitting device according to claim 1, wherein the reflective structure has an inner side surface which is in contact with the side surface of the LED chip, and an inner side surface which is in contact with the inclined side surface of the fluorescent structure. The light emitting device according to claim 1, wherein a refractive index of the light transmitting layer is smaller than a refractive index of the fluorescent layer. The light-emitting device according to any one of claims 1-6, wherein the fluorescent structure further includes a lens array layer, and the lens array layer is formed on the fluorescent layer. The light-emitting device according to any one of claims 1-6, wherein the fluorescent structure further has another transparent layer, and the other transparent layer is formed under the fluorescent layer. The light-emitting device according to any one of claims 1-6, wherein a bottom surface of the reflective structure is inclined upward. The light-emitting device according to any one of claims 1-6, wherein, along a normal direction of a top surface of the fluorescent structure, the top surface of the fluorescent structure shields the reflective structure. The light-emitting device according to any one of claims 1-6, wherein a side surface of the fluorescent structure is partially exposed from the reflective structure. The light-emitting device according to any one of claims 1-6, wherein a top surface of the reflective structure is inclined downward from a top surface of the fluorescent structure. The light-emitting device according to any one of claims 1-6, further includes a substrate, the LED chip and the reflective structure are disposed on the substrate, and the LED chip is electrically connected to the substrate. The light-emitting device according to any one of claims 1-6, wherein the reflective structure has a width and a length, the width is not more than 2.0 mm, and the length is not more than 3.0 mm. A light-emitting device includes an LED chip having an upper surface, a lower surface opposite to the upper surface, a side surface, and an electrode group. The side surface is formed between the upper surface and the lower surface. The electrode group is disposed on On the lower surface; a fluorescent layer is disposed on the upper surface of the LED chip; a transparent structure is disposed on the fluorescent layer, which has a top surface, a bottom surface opposite to the top surface, and forms On a side surface between the top surface and the bottom surface, the size of the top surface is greater than or equal to the size of the bottom surface, and the bottom surface is located on the upper surface of the LED chip, wherein the fluorescent layer is disposed on the transparent structure. One of the bottom and the bottom; and a reflective structure covering the side of the LED chip and the side of the transparent structure, wherein a height of the reflective structure is not less than 0.1 times of a length of the LED chip and is not larger than the LED chip 5 times the length, and an outer edge of a top surface of the reflective structure is lower than the top surface of the light transmitting structure, but higher than a top surface of the fluorescent layer.