KR101908449B1 - Light emitting device with aymeetrical radiation pattern and manufacturing method of the same - Google Patents

Abstract

Discloses a monochrome chip scale packaging light emitting diode device having asymmetric radiation patterns and reflective structures such as flip chip LED semiconductor die. A white light wide-area spectral CSP LED with an asymmetric radiation pattern is also disclosed which further includes the phosphorescent structure of a CSP LED device. The phosphorescent structure covers at least the upper surface of the LED semiconductor die. The reflective structure adjacent to the LED semiconductor die and the phosphorescent structure reflects at least partial light rays emitted from the edge surface of the LED semiconductor die or the edge surface of the phosphorescent structure, thereby forming a radiation pattern asymmetrically. Also disclosed is a method of manufacturing the CSP LED device. CSP LED devices are suitable for applications that require asymmetric illumination while maintaining the advantages of small form factors without the use of additional optical lenses.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device having an asymmetric radiation pattern,

This application claims priority to Taiwanese patent application No. 105102658 filed on January 28, 2016 and Chinese patent application No. 201610075824.4 filed on February 3, 2016, and Taiwan patent application filed on the same date Lt; / RTI >

The present invention relates to a light-emitting device and a method of manufacturing the same, and more particularly to a chip-scale package light emitting device including a light emitting diode (LED) semiconductor die for generating electromagnetic radiation during operation device.

LEDs are used in a variety of applications such as traffic lights, backlight units, general lighting, portable devices, and automotive lighting. The LED semiconductor die is disposed in a package structure such as a lead frame to form a package LED device. Can be further disposed and covered by photoluminescent materials such as phosphors to form phosphor converted white LED devices.

Among them, a plastic leaded chip carrier (PLCC) LED device can be divided into two types along the illumination direction: a top-view LED device and a side-view LED device have. Flat LED devices are used in general lighting or directly as a backlight source for direct backlit LED TVs while side LED devices are used as backlights for edge-lit displays such as LED TVs or cell phone display panels It is used as a source. The planar LED or side LED includes a light emitting surface, for example a rectangular light emitting surface, the optical axis of which is specified by a vertical axis perpendicular to the plane of the light emitting surface and passes through the center of the light emitting surface. In the present invention, a first horizontal direction and a second horizontal direction are specified for illumination, a first horizontal direction is perpendicular to the second horizontal direction, and a first horizontal direction and a second horizontal direction Both in the horizontal direction are perpendicular to the vertical optical axis. The first horizontal direction is further specified to coincide with the longitudinal direction of the LED device and the second horizontal direction is specified to coincide with the width direction of the LED device. It can be seen that when the optical radiation pattern is measured across a first horizontal direction or a second horizontal direction of a planar (or lateral) LED device, the two radiation patterns are very similar. Because a planar LED device or side-by-side LED device typically includes a similar light-emission pattern along the first horizontal or second horizontal direction, the plastic lead-chip carrier (PLCC) LED device exhibits a symmetrical radiation pattern.

An LED device that includes a symmetric radiation pattern can not meet the requirements of some applications that specify an asymmetric light source. For example, a streetlight typically exhibits a radiation pattern such as "batwing" Another example is an LED device having a rectangular light emitting surface as an LED light source for use in a backlight unit that is part of a side-view LED TV or a portable electronic device. More preferably, the asymmetric radiation pattern provides a large viewing angle radiation pattern along the longitudinal direction of the LED device, with the result that the larger viewing angle radiation pattern coincides with the orientation of the light guide plate for the backlight unit, resulting in a more uniform light distribution . Therefore, the side-view light source can reduce dark spots inside the light guide plate, or alternatively reduce the amount of LED devices included. Further, such a side-view light source is also specified to provide a small viewing angle light radiation pattern along the width direction of the LED device, resulting in the incident light incident on the LED device coinciding with the thickness direction of the light guide (plate) It is possible to reduce the optical loss since it passes through a thin light guide plate having efficiency.

In general, a flat PLCC LED device or a side PLCC LED device has three components for manufacturing: a lead frame including a reflective-cup housing structure formed through a molding process; A semiconductor die, and a photoluminescent material, such as a phosphor. A PLCC-type LED device with a symmetrical radiation pattern together with a secondary optical lens that modifies the radiation pattern to achieve the generally required asymmetric light radiation pattern when specific asymmetric radiation patterns are specified for a particular lighting application is solved. Such a solution would significantly increase manufacturing costs. It also requires additional space to accommodate the secondary optical lens, which is not suitable for final product design for small home appliances. If the space constraint can not include an optical lens for modifying the irradiated light radiation pattern in the PLCC type LED device, an asymmetric reflective cup of the lead frame is manufactured and solved. For example, both sides of the reflective cup structure are optically reflected such that the radiation pattern along the direction includes a smaller viewing angle and both sides of the cup are optically transparent so that the radiation pattern along the direction has a larger viewing angle . However, the asymmetrical reflective cups of this kind, including two transparent sides, are very difficult to manufacture. In other words, there is a need for a low-cost, state-of-the-art method for realizing an asymmetric optical radiation pattern utilizing a PLCC type LED device.

As household appliances such as LED TVs or portable electronic devices become ever thinner or smaller in size, PLCC-type LED devices such as backlight sources must also be reduced in size. In this trend, chip scale package (CSP) LED devices are attracting more attention from the LED industry with a small form factor. For example, CSP LED devices have been introduced to further reduce the size of the light source by replacing the widely used flat PLCC type LED devices in direct backlit LED TVs. In this way, a higher light intensity can be realized, thereby reducing the amount of LED devices used. The smaller form factor of the CSP LED device also facilitates the design of smaller secondary optical lenses, resulting in thinner TVs.

According to illumination geometry, CSP LED devices can be divided into two types: 1) top emitting CSP LED devices and 2) five-surface emitting CSP LED devices. Top-Emitting CSP LED devices are fabricated to cover the four peripheral marginal sides of an LED semiconductor die incorporating the deposited reflective material, and the light is primarily or individually irradiated from the top surface. Therefore, top-emitting CSP LED devices include smaller radiation patterns like PLCC-type LED devices with smaller viewing angles (approximately 120 degrees). On the other hand, the light can be radiated outward through the top surface and the four peripheral edge surfaces of the five-sided CSP LED device. Therefore, a five-sided light emitting CSP LED device includes a larger viewing angle (140 to 160 degrees). However, similar to PLCC type LED devices, top-emitting CSP LED devices and five-sided emitting CSP LED devices all contain symmetrical light-emitting patterns and are therefore unsuitable for applications that specify asymmetric light-emitting patterns.

Another approach is to utilize a CSP LED device and a secondary optical lens together to produce an asymmetric radiation pattern. This approach, however, not only significantly increases production costs, but also requires additional space to accommodate optical lenses, thereby hindering the benefits of utilizing small form factor CSP LED devices. In other words, there is still no effective solution to realize asymmetric radiation patterns using CSP LED devices. Therefore, it is desirable to provide an effective solution at low cost to realize an asymmetric light radiation pattern while maintaining the advantage of being a small form factor of a CSP LED device.

One object in accordance with some embodiments of the present invention is to provide a CSP LED device and method of manufacturing the same and to provide a CSP LED device having a viewing angle of at least one specific direction (e.g., a first horizontal direction or a second horizontal direction of the light emitting surface) To provide an asymmetric radiation pattern while maintaining a small form factor that is an advantage of CSP devices.

To achieve the above object, a CSP LED device according to some embodiments of the present invention includes an LED semiconductor die, a photoluminescent structure, and a reflective structure. The LED semiconductor die comprises a flip-chip LED semiconductor (not shown) including an upper surface, a substantially parallel but opposing lower surface, an edge surface, and a set of electrodes. The edge surface is formed and extends between the outer perimeter of the outer perimeter of the upper surface and the electrode set is disposed on the lower surface of the LED semiconductor die. The phosphorescent structure includes an upper surface, a lower surface, and an edge surface, and the lower surface of the phosphorescent structure covers at least the upper surface of the LED semiconductor die. Further, the phosphorescent structure includes a photoluminescent layer and a supernatant light-transmitting layer disposed in the phosphorescent layer. In one preferred embodiment, the phosphorescent structure selectively covers the entire upper surface of the LED semiconductor die and the two side edges of the edge surface. Specifically, the two side edges of the edge surface of the LED semiconductor die, which are orthogonal to the first horizontal direction, are covered by the phosphorescent structure while the two side edges of the edge surface of the LED semiconductor die, which is perpendicular to the second horizontal direction, Do not. The reflective structure at least partially covers the edge surface of the LED semiconductor die and the edge surface of the phosphorescent structure. In a preferred embodiment, the reflective structure selectively covers two side edges of the edge surface of the LED semiconductor die and two side edges of the edge surface of the phosphorescent structure perpendicular to the second horizontal direction, The two side edges of the edge surface of the LED semiconductor die, which is at right angles to it, are covered by a phosphorescent structure. According to a preferred embodiment, the viewing angle of the CSP LED device along the first horizontal direction is larger than the viewing angle along the second horizontal direction, thereby forming a CSP LED device having an asymmetrical radiation pattern.

In order to achieve the above object, a method of manufacturing a CSP LED device according to some embodiments of the present invention includes the steps of 1) forming a phosphorescent structure in a LED semiconductor die including a phosphorescent layer and a supercritical liquid crystal layer, Between the top surfaces of the LED semiconductor die; 2) forming a reflective structure to cover at least a portion of the edge surface of the phosphorescent structure and at least a portion of the edge surface of the LED semiconductor die.

Other aspects and embodiments of the invention are also contemplated. It is to be understood that both the foregoing summary and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Therefore, some beneficial advantages to embodiments according to the present invention are described as follows. The reflective structure covers at least partially the edge surface of the LED semiconductor die and reflects light rays emitted from the edge surface of the LED semiconductor die along the first and / or second horizontal direction to form a first horizontal and / The viewing angle along the horizontal direction is reduced to generate an asymmetric radiation pattern as a whole.

Therefore, a CSP LED device according to embodiments of the present invention can provide an asymmetric optical radiation intensity pattern without additional optical lens, thereby maintaining a small form factor that is an advantage of a CSP device and consequently the design of a thinner or smaller electronic device . For example, when using a CSP LED device having an asymmetric radiation pattern in a backlight unit of a side-view LED TV, a mobile phone or a tablet PC, a large viewing angle of the CSP LED device is determined by the in- Direction. This design can increase the apex distance between two adjacent CSP LED devices to reduce the amount of CSP LED devices used. Further, a larger viewing angle along the horizontal direction can reduce the dark spot inside the light guide plate. On the other hand, since a smaller viewing angle of the CSP LED device can be disposed along the thickness direction of the light guide plate, it is possible to reduce the light loss and improve the conduction efficiency of light incident from the CSP LED device to the light guide plate. Also, CSP LED devices, including small form factors, can further reduce space along the edge of the backlight unit, resulting in a smaller frame design while maintaining the same field of view.

1A is a schematic diagram of a three-dimensional (3D) view illustrating a CSP LED device according to an embodiment of the present invention.
1B is a schematic diagram of a 3D view of a CSP LED device in accordance with an embodiment of the invention.
1C is a schematic diagram of a cross-sectional view illustrating a CSP LED device in accordance with one embodiment of the present invention.
1D is a schematic diagram of a cross-sectional view illustrating a CSP LED device in accordance with an embodiment of the present invention.
1E, 1F, and 1G are schematic diagrams of a 3D view illustrating a CSP LED device in accordance with one embodiment of the present invention.
2A and 2B are schematic views of a 3D view showing a CSP LED device according to another embodiment of the present invention.
Figures 2C and 2D are schematic diagrams of cross-sections illustrating a CSP LED device in accordance with another embodiment of the present invention.
3A and 3B are schematic views of a 3D view showing a CSP LED device according to another embodiment of the present invention.
Figures 3C and 3D are schematic diagrams of cross-sections illustrating a CSP LED device according to another embodiment of the present invention.
4A and 4B are schematic diagrams of a 3D view showing a CSP LED device according to another embodiment of the present invention.
4C and 4D are schematic diagrams of cross-sections illustrating a CSP LED device in accordance with another embodiment of the present invention.
5A is a representative light emission pattern of a CSP LED device to be compared.
5B is a representative light emission pattern of a CSP LED including an asymmetric radiation pattern according to an embodiment of the present invention.
6A, 6B, 6C, 6D, 6E, 7A, 7B, 8A, 8B and 8C illustrate a fabrication process for fabricating a CSP LED device according to an embodiment of the present invention Outline.
FIGS. 9A, 9B, 10A, 10B, 10C, 11A, 11B, 12A and 12B are schematic views showing a manufacturing process for manufacturing a CSP LED device according to another embodiment of the present invention.
FIGS. 13, 14, 15A, 15B, 16A, 16B, 16C, 17A, 17B, 18A and 18B are schematic views showing a manufacturing process for manufacturing a CSP LED device according to another embodiment of the present invention.

The following definitions apply to some of the technical aspects described for some embodiments of the present invention. Likewise, this definition can be expanded in accordance with the present description.

As used in this description, the singular terms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a layer may include multiple layers unless the text clearly teaches.

As used in this description, the term "set" refers to a collection of one or more parts. Thus, for example, a layer set may comprise one layer or multiple layers. A set of parts may also refer to members of the set. A set of parts may be the same or different. In some instances, a set of components may share one or more common features.

As used in this description, the term "adjacent" Adjacent components may be released from each other or may be in substantial or direct contact with each other. In some cases, adjacent components may be interconnected or formed integrally with each other. In the description of some embodiments parts are provided "above" or "above" another part, as well as when there are one or more frayed parts located between the electronic part and the latter part, as well as when the electronic part is directly on the latter part For example, directly physically contacted). In the description of some embodiments, a part is provided beneath another part, as well as where one or more fused parts are located between the electronic part and the latter part, as well as where the electronic part is directly under the latter part ).

As used in this description, the terms "connect," " connected, " and "connection, " Connected components can be connected directly to each other or indirectly connected to each other as through another set of components.

As used in this description, the terms "approximately "," substantially "and" substantial "refer to a considerable degree or extent. When used in connection with an event or situation, the terms may refer to instances where an event or circumstance occurs precisely as well as instances where an event occurs, such as an event or situation describing typical tolerance levels of manufacturing operations described herein . For example, when used in connection with a numerical value, the terms are less than or equal to ± 5% of the numerical value, less than or equal to ± 4%, less than or equal to ± 3%, less than or equal to ± 2% Less than or equal to ± 1%, less than or equal to ± 0.5%, less than or equal to ± 0.1%, or less than or equal to ± 0.05%. have. In the case of "substantially visually transparent", the term may indicate that the light transmittance is at least 80% in the wavelength range of the desired spectrum, such as at least 85%, at least 90% or at least 95%. In the case of " right angle "or" substantially orthogonal ", the term is not more than +/- 4 degrees, +/- 3 degrees, less than +/- 2 degrees, less than +/- 1 degree, less than +/- 0.5 degrees, less than +/- 0.1 degrees, It may indicate that the relative direction is 90 degrees as well as the variable range of +/- 5 degrees or less with respect to 90 degrees as follows.

The term "efficiency" or "quantum efficiency, " as used in this description in relation to phosphorescence, refers to the ratio of the number of output photons to the number of input photons.

The term "size" as used in this description refers to a particular dimension. In the case of a spherical object (for example, a particle), the size of the object may indicate the dimension of the object. If the object is non-spherical, the size of the object may indicate the average of various orthogonal dimensions of the object. Thus, for example, the size of a spherical object may indicate the average of the major axis and minor axis of the object. If we refer to a set of objects as having a particular size, then the objects are considered to be able to contain a distribution of their magnitudes and sizes. Thus, the size of an object set such as that used in this description may indicate a typical size of a distribution of sizes, such as an average size, a medium size, or a maximum size.

Figures 1A and 1B are schematic diagrams of a 3D view, and Figures 1C and 1D are schematic diagrams of cross-sectional views of a CSP LED device in accordance with an embodiment of the present invention. To be clear, the first horizontal direction D1 and the second horizontal direction D2 are specified in the present invention as follows. The first horizontal direction D1 is specified to coincide with the longitudinal direction of the CSP LED device 1A and the second horizontal direction D2 is perpendicular to the first horizontal direction D1 and the width of the CSP LED device 1A Direction. ≪ / RTI > Both the first horizontal direction D1 and the second horizontal direction D2 are perpendicular to the optical axis of the CSP LED device 1A and the optical axis is a vertical axis passing through the geometric center of the light emitting surface of the CSP LED device 1A (Not shown). The CSP LED device 1A includes an LED semiconductor die 10, a phosphorescent structure 20, and a reflective structure 30. The detailed description is as follows.

1C, the LED semiconductor die 10 is preferably a flip chip type LED semiconductor, including an upper surface 11, a lower surface 12, an edge surface 13, and an electrode set 14. The upper surface 11 and the lower surface 12 are formed substantially parallel and face each other. The upper surface 11 and the lower surface 12 are rectangular and the first horizontal direction D1 coincides with two edge lines in the longitudinal direction of the upper surface 11 (or the lower surface 12) Can coincide with the other two corner lines in the width direction.

An edge surface 13 is formed and extends between the upper surface 11 and the lower surface 12 and connects the outer surface of the upper surface 11 and the outer surface of the lower surface 12. In other words, the edge surface 13 is formed along the outer frame of the outer frame 12 and the outer frame 12 of the upper surface 11. The edge face 13 comprises two pairs of side edges 131 and the side edges 131a of the first pair are arranged to face each other and are perpendicular to the first horizontal direction D1, The side edges 131b of the second pair are arranged to face each other as shown in Fig. 1C and perpendicular to the second horizontal direction D2.

The electrode set 14 or a plurality of electrodes are disposed on the lower surface 12. Power (not shown) is supplied to the LED semiconductor die 10 through the set of electrodes 14 to generate an electro-luminescence. The light rays L generated by the LED semiconductor die 10 as shown in Figures 1C and 1D are mostly illuminated from the top surface 11 and a portion of the light rays L is illuminated from the edge surface 13. No electrode is disposed on the top surface 11 of the flip chip type semiconductor die 10 of the illustrated embodiment.

The phosphorescent structure 20 including the top surface 21, the bottom surface 22 and the edge surface 23 can change the wavelength of the light ray L emitted from the LED semiconductor die 10. The upper surface 21 and the lower surface 22 are arranged in a rectangular shape so as to face each other. The two corner lines of the upper surface 21 (or the lower surface 22) coincide with the first horizontal direction D1 and the other two corner lines coincide with the second horizontal direction D2. In other words, the upper surface 21 is formed substantially parallel to the plane specified by the first horizontal direction D1 and the second horizontal direction D2. Both the upper surface 21 and the lower surface 22 are disposed substantially parallel and coincide with the horizontal plane specified by D1 and D2.

An edge surface 23 is formed and extends between the upper surface 21 and the lower surface 22 and connects the outer edge of the upper surface 21 and the outer edge of the lower surface 22 of the upper surface 21. In other words, the rim surface 23 is formed along the outer rim of the outer rim and bottom surface 22 of the upper surface 21. The edge surface 23 includes two pairs of side edges 231 with the side edges 231a of the first pair facing each other as shown in Figure 1D and the side edges 231b of the second pair As shown in Fig. 1C.

Furthermore, since the surface area of the upper surface 21 of the phosphorescent structure 20 is larger than the surface area of the lower surface 22, at least one pair of side edges 231a or 231b of the edge surface 23 is located on the upper surface 21 or the lower surface 22 ). For example, the surface area of the upper surface 21 may be at least about 1.2 times, at least about 1.3 times, at least about 1.4 times, or at least about 1.1 times at least about 1.5 times the surface area of the lower surface 22. In this embodiment, the first pair of side edges 231a are inclined with respect to the first horizontal direction D1 and the side edges 231b of the second pair are perpendicular to the second horizontal direction D2. For example, the inclination angle between the side edges 231a with respect to the first horizontal direction D1 may be about 88 degrees or less, about 85 degrees or less, or about 90 degrees or less, such as about 80 degrees or less.

In this embodiment of the CSP LED device 1A, the phosphorescent structure 20 includes a phosphorescent layer 201 and a supernatant liquid-crystal layer 202, and the formed supernatant liquid-crystal layer 202 is disposed in the phosphorescent layer 201. The upper surface of the supernatant liquid-repellent layer 202 is the upper surface 21 of the entire phosphorescent structure 20 and the lower surface of the translucent layer 201 is the lower surface 22 of the entire phosphorescent structure 20. Both the supernatant light-emitting layer 202 and the phosphorescent layer 201 pass the light ray L. Thus, the composition material may comprise a substantially transparent material such as a silicone resin. The composition material of the phosphorescent layer 201 may further include a phosphorescent material mixed in the light emitting material. As a result, when the light L emitted from the LED semiconductor die 10 passes through the phosphorescent layer 201, the partial light L is converted down-converted to a longer wavelength by the phosphorescent material, Layer 202 as shown in FIG.

The phosphorescent layer 201 may be formed by the method disclosed in US2010 / 0119839 and one or more layers of the phosphorescent material and the light emitting material are arranged in order to form the phosphorescent layer 201. [ Therefore, the phosphorescent layer 201 formed by this method may have a multi-layer structure including at least one light-transmitting layer and at least one phosphorescent layer (not shown) stacked on top of each other. The contents of the U.S. Patent Application Publication is incorporated herein by reference in its entirety.

The supernatant light-emitting layer 202 may function as an environmental barrier layer to prevent the phosphorescent layer from being contaminated or damaged even if the wavelength of the incident light L is not changed. Furthermore, the supernatant liquid-crystal layer 202 improves the mechanical rigidity of the phosphorescent structure 20, so that the phosphorescent structure 20 is not easily bent, and thus can be more appropriately managed in mass production.

The structure of the CSP LED device 1A is arranged in the LED semiconductor die 10 so that the lower surface 22 of the phosphorescent structure 20 is attached to the upper surface 11 of the LED semiconductor die 10, do. The upper surface 21 and the edge surface 23 of the phosphorescent structure 20 will also be disposed on the upper surface 11 of the semiconductor die 10. In other words, the phosphorescent structure 20 covers the upper surface 11 of the LED semiconductor die 10 by the phosphorescent layer 201, so that the supercritical solution light-transmitting layer 202 is released from the upper surface 11.

Reflective structure 30 may reflect light ray L to define the direction of radial illumination of light ray L. [ The reflective structure 30 at least partially covers the edge surface 13 of the LED semiconductor die 10 and at least partially covers the edge surface 23 of the phosphorescent structure 20. For example, at least a pair of side edges 131a or 131b of the edge surface 13 of the LED semiconductor die 10 are covered by the reflective structure 30 and the side edges of at least one pair of the phosphorescent structures 20 (231a or 231b) is also covered by the reflective structure (30). Two pairs of side edges 231, including two pairs of side edges 131 and 231a and 231b, including 131a and 131b in this embodiment of the CSP LED device 1A, The upper surface 21 of the phosphorescent structure 20 is not covered by the reflective structure 30. So that the light L can be reflected (or absorbed) by the reflective structure 30 at the edge surface 13 and the edge surface 23 and selectively escape outward at the top surface 21 of the phosphorescent structure 20 .

Preferably, the reflective structure 30 covers and adjoins the edge surface 13 of the LED semiconductor die 10 and the edge surface 23 of the phosphorescent structure 20, so that the reflective structure 30 and the edge surface 13). ≪ / RTI > Similarly, there is substantially no gap between the reflective structure 30 and the edge surface 23. The reflective structure 30 thus includes an inner edge surface 31 that is square with respect to the edge surface 13 of the LED semiconductor die 10. The inner edge surface 32 of the reflective structure 30 is also angled with respect to the edge surface 23 of the phosphorescent structure 20. Preferably, the top surface 33 of the reflective structure 30 may be substantially the same height as the top surface 21 of the phosphorescent structure 20. The reflective structure 30 also includes an outer edge surface 34 and the outer edge surface 34 is vertical.

In one embodiment, the reflective structure 30 may be fabricated using a transparent, malleable resin material, wherein light scattering particles are distributed within the structure. More specifically, it is possible to form a reflective structure 30 by forming a ferrofatty structure such as polyphthalamide (PPA), polycyclohexylene-dimethylene terephthalate (PCT) or epoxy molding compound (EMC) Resin material is used. Another typical malleable resin material may be a transparent silicone resin having a high refractive index (RI) (preferably between about 1.45 and about 1.55) or a low refractive index silicone resin (preferably having a refractive index of between about 1.35 and about 1.45) . Representative light scattering particles distributed in a transparent and malleable resin material include titanium dioxide (TiO ₂ ), boron nitride (BN), silicon dioxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), or a combination thereof. Other oxides, nitrides and ceramic particles can be used. The particle size of the light scattering particles is preferably about half of the wavelength of the visible spectrum (e.g., about 150 nm to about 450 nm). It is also understood that the reflective structure 30 may be formed of other electronic encapsulation or packaging materials.

The above description is a technical description of each component of the CSP LED device 1A and includes at least the following technical features.

1C and FIG. 1D, according to the embodiment of the CSP LED device 1A, the light L emitted from the LED semiconductor die 10 first enters the phosphorescent layer 201 and enters the supernatant liquid crystal layer 202, And finally illuminated from the top surface 210 of the phosphorescent structure 20. [ The light beam L is not emitted directly after passing through the phosphorescent layer 201 and the light L passing through the phosphorescent layer 201 of the CSP LED device 1A continues to be emitted from the inside of the supercritical liquid crystal layer 202 Move. In other words, the supernatant light-emitting layer 202 defines an optical cavity for creating the radiation intensity pattern form in this embodiment of the CSP LED device 1A together with the reflective structure 30. Therefore, the viewing angle of the CSP LED device 1A can be limited.

More specifically, FIG. 1D shows a schematic view of a cross-sectional view with a section along the first horizontal direction D1. The pair of side edges 231a are inclined as shown in FIG. 1D, so that the light beam L can be irradiated on the upper surface 21 having a relatively larger viewing angle. Conversely, FIG. 1C shows a schematic view of a CSP LED device 1A in a cross-sectional view with a cutaway along the second horizontal direction D2. The side edge 231b is substantially vertical so that the light ray L can be emitted from the top surface 21 with a smaller viewing angle. Therefore, an asymmetrical light emission pattern of the CSP LED device 1A can be realized.

The length of the upper surface 21 along the first horizontal direction D1 is preferably longer than the width of the upper surface 21 along the second horizontal direction D2. For example, the length of the top surface 21 may be at least about 1.2 times the width of the top surface 21, at least about 1.3 times, at least about 1.4 times, or at least about 1.1 times, such as at least about 1.5 times. In this arrangement, the aspect ratio specified by the length divided by the height (or thickness) of the supernatant light-emitting layer 202 is larger than the aspect ratio specified by the width divided by the height (or thickness) of the supernatant light- It is understood that the larger the aspect ratio, the larger the viewing angle. It is therefore advantageous to combine the effect of a larger aspect ratio along the first horizontal direction with the effect of a sloping reflector to form an asymmetric radiation pattern for the CSP LED device 1A.

The CSP LED device 1A capable of providing different viewing angles with respect to the first horizontal direction and the second horizontal direction along the above description is suitable for applications that specify asymmetric roughness.

1E, the phosphorescent structure 20 of the CSP LED device 1A can be replaced with a substantially transparent translucent layer 202 having a shape similar to that of the phosphorescent structure 20. [ In this structure, the CSP LED device 1A includes the LED semiconductor die 10, the light-transmitting layer 202, and the reflecting structure 30, but omits the phosphorescent layer 201, The light ray does not contact the phosphorescent material as it passes through the light- This embodiment can be used to produce a monochromatic CSP LED device that emits a beam of monochromatic spectrum (red, green, blue, ultraviolet, infrared, etc.) having an asymmetrical radiation pattern. Similarly, a technique using a transparent light-transmitting layer substantially free of a phosphorescent material as described above can be applied to other embodiments described in the present invention.

As shown in FIG. 1F, the CSP LED device 1A may further include a micro-lens array layer on the light emitting surface. The microlens array layer is formed at the same time in the same manufacturing process for forming the supercritical fluid-emitting layer 202 using a molding method or the like. Thus, the microlens array layer and the supernatant liquid-crystal layer 202 can be fabricated simultaneously in a single manufacturing process. As shown in FIG. 1F, the supernatant light-emitting structure 202 'includes a micro-lens array layer and may include a plurality of microstructures arranged in order or randomly. Other variants of the microstructure may be hemispherical, pyramidal, conical, columnar, etc., or a rugged surface. Thus, the supernatant light-emitting structure 202 'comprising the microlens array layer reduces the amount of light reflected back to the interface of the supernatant light-emitting structure 202' and the surrounding environment due to the overall internal reflection, . Thus, the overall light extraction efficiency and luminous efficacy of the CSP LED device 1A are improved. The technique of bonding the microlens array layer to the surface of the supernatant light-transmitting layer as described above can be applied to other embodiments according to the present invention.

As shown in FIG. 1G, the CSP LED device 1A may be a submount (which may be a ceramic substrate, a glass substrate, a silicon substrate, a printed circuit board (PCB) or a metal core printed circuit board (MCPCB) (70). The submount 70 includes a circuit (not shown) that is capable of conducting electrical power through a pair of bonding pads, typically located under the submount 70. Therefore, the submount 70 serves as a fan-out pad for connecting the electrodes of the electric furnace CSP LED device 1A, so that the application of the CSP LED device 1A and the application of the surface mount (Surface Mounting) bonding process. The technique of coupling the sub-mount 70 in this way can be applied to other embodiments according to the present invention.

The above is a detailed description of an embodiment of the CSP LED device 1A. A detailed description of another embodiment of the CSP LED device according to the present invention is as follows. It is understood that some detailed descriptions of features and advantages that can be seen through embodiments of the following light emitting device are similar to the features and advantages of the CSP LED device 1A and therefore will be omitted for brevity purposes.

Figs. 2A and 2B are schematic views of a 3D view and Figs. 2C and 2D are schematic views of cross-sectional views of a CSP LED device 1B according to another embodiment of the present invention. The difference between the CSP LED device 1B and the CSP LED device 1A is that the reflective structure 30 has at least one pair of side edges (as shown in the cross-sectional view along the second horizontal direction D2 of FIG. 2C) 231b. On the other hand, the reflective structure 30 is exposed without covering the other pair of side edges 231a of the phosphorescent structure 20, as shown in the cross-sectional view with the section along the first horizontal direction D1 . Another difference is that the surface area of the phosphorescent structure 20 of the CSP LED device 1B is larger than the surface area of the LED semiconductor die 10. The more detailed description of the technology is as follows.

The length of the lower surface 22 of the phosphorescent structure 20 as seen through the cut surface along the first horizontal direction D1 (longitudinal direction) shown in FIG. 2D is longer than the length of the upper surface 11 of the semiconductor die 10 long. The width of the lower surface 22 of the photoluminescent structure 20 is larger than the width of the upper surface 11 of the semiconductor die 10 as shown through a cut plane along the second horizontal direction D2 (width direction) Lt; / RTI > The width of the lower surface 22 of the phosphorescent structure 20 is preferably slightly larger than the width of the upper surface 11 of the semiconductor die 10 to prevent direct leakage of light rays that do not pass through the phosphorescent structure 20.

The edge surface 23 of the phosphorescent structure 20 includes two pairs of side edges 231 including a pair 231a and another pair 231b. As shown in FIG. 2C, the pair of side edges 231b are perpendicular to the second horizontal direction D2 and are covered by the reflective structure 30. As shown in FIG. As shown in Figure 2D, the other pair of side edges 231a are perpendicular to the first horizontal direction D1 and are not covered by the reflective structure 30. It is understood that the four side edges 131a and 131b of the edge surface 13 of the LED semiconductor die 10 are all covered by the reflective structure 30. [

In such a configuration, light rays L (including scattered light and non-scattered light) traveling toward the pair of side edges 231b when the light L is emitted from the LED semiconductor die 10, ) To have a smaller viewing angle. On the other hand, the light rays L moving toward the pair of side edges 231a are not absorbed or reflected by the reflecting structure 30, and thus have a larger viewing angle.

The CSP LED device 1B, which can provide different viewing angles with respect to the first horizontal direction and the second horizontal direction according to the above description, is suitable for an application for specifying asymmetric roughness. The pair of side edges 231a of the CSP LED device 1B are not covered by the reflective structure 30 having the cut surface along the first horizontal direction D1 as compared with the CSP LED device 1A, It is possible to provide a larger viewing angle along the horizontal direction D1.

3A and 3B are schematic views of a 3D view and FIGS. 3C and 3D are schematic views of cross-sectional views of a CSP LED device 1C according to another embodiment of the present invention. The difference between the CSP LED device 1C and the CSP LED device 1B is that at least a portion of the edge surface 13 of the LED semiconductor die 10 of the CSP LED device 1C is not covered by the reflective structure 30 Is covered by the phosphorescent structure (20).

3C and 3D, the edge surface 13 includes at least two pairs of side edges 131a and 131b. In addition to covering the top surface 11 of the LED semiconductor die 10, the phosphorescent layer 201 further covers the side edges 131a and / or 131b and then extends outward. The phosphorescent layer 201 has an upper portion 205 covering the upper surface 11 of the LED semiconductor die 10, a corner portion 206 covering the side edges 131a and / or 131b and a first horizontal direction D1 And / or an extension 207 extending outwardly from the edge 206 along the second horizontal direction D2. As a result, the light emitted from the side edges 131a and / or 131b of the LED semiconductor die 10 is guided along the first horizontal direction D1 and / or the second horizontal direction D2 to the corner portion 206 and the extension portion 207 Can be converted into a lower energy beam of a different wavelength by the phosphorescent layer 201. [

3C, the side edge 131b with the cut plane along the second horizontal direction D2 is first covered by the phosphorescent structure 20 and further covered by the reflective structure 30. As shown in Fig. Preferably, the side edges 131b may be directly covered by the reflective structure 30 (not shown). The side edge 131a is covered by the phosphorescent structure 20 along with the section along the first horizontal direction D1 but the phosphorescent structure 20 is not covered by the reflective structure 30. [ In other words, the reflective structure 30 is not used to define the viewing angle along the cut surface that coincides with the first horizontal direction D1.

The light rays L generated within the LED semiconductor die 10 can be emitted directly from the LED semiconductor die 10 through the side edge 131a as seen through the cut- And then emitted from the CSP LED device 1C through the phosphorescent structure 20 that is not reflected by the reflective structure 30. Therefore, the CSP LED device 1C along the first horizontal direction D1 provides a larger viewing angle. Conversely, the CSP LED device 1C provides a smaller viewing angle because the ray L along the second horizontal direction is confined through reflection due to the reflective structure 30. [ The CSP LED device 1C, which can provide different viewing angles with respect to the first horizontal direction and the second horizontal direction according to the above description, is suitable for an application for specifying asymmetric roughness.

Compared to the CSP LED device 1B, since the edge surface 13 of the LED semiconductor die 10 is not covered by the reflective structure 30 along the first horizontal direction D1, It is possible to further provide a larger viewing angle along the horizontal direction D1.

(Not shown) of the CSP LED device 1C is as follows: One side edge of the pair of side edges 131b perpendicular to the second horizontal direction is covered by the reflective structure 30 And one lateral edge of the other pair of side edges 131a perpendicular to the first horizontal direction D1 is also covered by the reflective structure 30. [ Therefore, the radiation pattern of the light ray L along the second horizontal direction D2 itself is asymmetric. Similarly, the radiation pattern along the first horizontal direction D1 itself is also asymmetric.

Figs. 4A and 4B are schematic diagrams of a 3D view and Figs. 4C and 4D are schematic diagrams of cross-sectional views of a CSP LED device 1D according to another embodiment of the present invention. Fig. The difference between the CSP LED device 1D and the CSP LED device 1C is that at least the CSP LED device 1D is disposed below the phosphorescent layer 201 to provide at least a portion of the edge surface 13 of the LED semiconductor die 10 And a reflective under-layer (40) covering the reflective layer (40). The reflective sublayer 40 preferably includes an upper surface 41 attached to a corner portion 206 of the phosphorescent layer 201 and the extension portion 207 and an upper surface 41 attached to the edge surface 13 of the LED semiconductor die 10. [ And an edge surface (43). The thickness of the sub reflection layer 40 is not thicker than the thickness of the LED semiconductor die 10.

A portion of the light L is re-directed toward the extension 207 of the phosphorescent layer 201 after the light L emitted from the LED semiconductor die 10 moves inside the phosphorescent layer 201. [ do. Therefore, the light beam L can not be utilized efficiently, resulting in energy loss of the light beam and reducing the luminous efficiency. The light ray L transmitted through the arrangement of the reflection lower layer 40 under the phosphorescent layer 201 toward the extension 207 can be reflected by the reflection lower layer 40 so that the light ray L is incident on the phosphorescent structure 20, So that it can be removed from the upper surface 21 and the pair of side edges 231a. Thus, the overall luminous efficiency of the CSP LED device 1D is improved.

Figures 5A and 5B illustrate examples of optical measurement results of a light emitting pattern of a CSP LED device having a length of approximately 1500 [mu] m and a width of approximately 1200 [mu] m. 5A shows the result of optical measurement of the light emission pattern of the top-emitting CSP LED device to be compared. The light emission patterns along the first horizontal direction D1 (longitudinal direction) and the second horizontal direction D2 (width direction) are very similar to each other, and both are about 120 degrees at Full Width at Half Maximum (FWHM) And therefore includes a symmetrical radiation pattern. 5B shows the results of optical measurement of the light emission pattern of a CSP LED device 1C having an asymmetric radiation pattern according to the present invention. The light radiation pattern along the first horizontal direction D1 (longitudinal direction) is significantly different from the light radiation pattern and the radiation pattern profile along the second horizontal direction D2 (width direction). The measured full width half-width exhibits an asymmetric light radiation pattern of approximately 135 degrees in the first horizontal direction D1 and approximately 122 degrees in the second horizontal direction D2.

Thus, the CSP LED devices 1A, 1B, 1C, and 1D provide at least the following advantages. The asymmetric light radiation pattern can be realized without the introduction of a primary optical lens or a secondary optical lens, thus reducing the overall manufacturing cost in some applications that specify an asymmetric light source. Furthermore, space for coupling the optical lens is saved. In addition, the small form factor of CSP LED devices, including asymmetric radiation patterns, facilitates the design of smaller appliances. Thus, a CSP LED device including an asymmetric radiation pattern can be introduced as a light source for a backlight unit of a display panel for a side-view LED TV or a portable electronic device. The asymmetric radiation pattern provides a larger viewing angle radiation pattern along the longitudinal direction of the light guide plate of the backlight unit, thereby generating a more uniform light distribution. Therefore, the side-view light source can reduce the dark spot inside the light guide plate, or alternatively increase the apex distance between two adjacent CSP LED devices to reduce the amount of CSP LED devices included. Furthermore, the asymmetric radiation pattern provides a small viewing angle light radiation pattern along the thickness direction of the light guide plate, so that incident light emitted from the CSP LED device can pass through the thin light guide plate with higher transmission efficiency, thereby reducing light loss.

Furthermore, the technical content of forming a monochrome CSP LED device with an asymmetric radiation pattern disclosed through the LED device 1A is also applicable to the CSP LED devices 1B, 1C and 1D. Other technical details such as further including a microlens array layer or a submount substrate can also be applied to the CSP LED devices 1B, 1C and 1D.

A manufacturing method for manufacturing various embodiments of a CSP LED device according to the present invention is then described. Generally, the manufacturing process includes at least two major fabrication steps: placing the phosphorescent structure on the LED semiconductor die and covering at least one side of the edge surface of the phosphorescent structure and at least the same side of the edge surface of the LED semiconductor die Step. In addition, the description of the manufacturing method is as follows.

6A-8C illustrate a method of manufacturing an embodiment of a CSP LED device 1A according to the present invention.

The phosphorescent structure may be formed prior to the fabrication step of placing the phosphorescent structure 20 on the LED semiconductor die 10. Specifically, as shown in FIG. 6A, the phosphorescent layer 201 is first formed in a release layer 50. Then, as shown in Fig. 6B, a supernatant liquid-crystal layer 202 is formed and laminated on the phosphorescent layer 201. Fig. The release layer 50 is removed as shown in FIG. 6C to prepare a photoluminescent sheet 200 composed of the supernatant light-transmitting layer 20 and the phosphorescent layer 201. The formation of the phosphorescent layer 201 and the supercritical fluid-emitting layer 202 as described above can be realized by a method such as spraying, coating, printing, injection molding, or the like. Preferably, the phosphorescent layer 201 can be formed through the method disclosed in US2010 / 0119839.

When forming the phosphorescent sheet 200, the phosphorescent sheet 200 is then separated into a plurality of phosphorescent structures 20 through a singulation process, and in particular, at least one pair of inclined side surfaces 23 of the edge surface 23 To form the phosphorescent structure 20 including the edge 231a or 231b. An exemplary singulation process is a punching process that disassembles or separates the phosphorescent sheet 200 into a plurality of phosphorescent structures 20 with desired sloped edge surfaces. Specifically, as shown in FIG. 6D, the phosphorescent sheet 200 is disposed on another release layer (not shown) and is punched by a punching tool 60. The puncher 40 includes punching blades 61 which are connected to one another and arranged according to the required geometry of the phosphorescent structure 20. [ Therefore, the plurality of phosphorescent structures 20 can be formed through the phosphorescent sheet 200 having a single punching process using the punching machine 60. As shown in FIG. 6E, the pair of side edges 231a of the phosphorescent structure 20 are inclined. Instead of a punching process, a sawing or molding process can be utilized.

Further, the inclination angle of the inclined lateral edge 231a of the phosphorescent structure 20 is determined by various design factors such as the blade angle profile, the geometrical numerical value of the phosphorescent structure 20, the elasticity of the phosphorescent sheet 200, . ≪ / RTI > Such elements can be designed in advance to ensure the required inclination angle of the inclined side edge 231a. A specific description of the angle of inclination of the side edge 231a is disclosed in U.S. Patent Application No. 15 / 280,927 (also published as Taiwan Patent Application No. 104132711), the contents of which are incorporated herein by reference in their entirety.

It may be disposed on the LED semiconductor die 10 after the phosphorescent structure 20 is formed. Specifically, as shown in FIG. 7A, a plurality of LED semiconductor dies 10 are disposed in a release layer 50 'as an array of LED semiconductor dies 10 including a specified distance of vertices. Representative embodiments of release layer 50 'include ultraviolet (UV) release tape, thermal release tape, and the like. Preferably, each electrode set 14 of the array of LED semiconductor die 10 is forcedly placed and pressed into a soft release layer 50 '. This will prevent contamination of the electrode set 14 that occurs during subsequent processing. 7B, the array of phosphorescent structures 20 is then deposited on the top surface 11 of the pre-arrayed array of LED semiconductor dies 10. [ It is desirable to precisely adjust and adjust the attachment process so that the lower surface 22 of the phosphorescent structure 20 covers substantially the entire upper surface 11 of the LED semiconductor die 10. The phosphorescent structure 20 may be attached to the upper surface 11 of the LED semiconductor die 10 utilizing an adhesive material or an adhesive tape. Thus, an organic electroluminescent structure including the LED semiconductor die 10 and the phosphorescent structure 20 is formed and the phosphorescent layer 201 is between the upper liquid-pervious layer 202 and the upper surface 11 of the LED semiconductor die 10 .

The manufacturing process for forming the reflective structure 30 surrounding the organic electroluminescent structure is as follows. A resin material for manufacturing the reflective structure 30 is disposed as shown in FIG. 8A to cover the edge surface 13 of the LED semiconductor die 10 and the edge surface 23 of the phosphorescent structure 20 at the same time To form a reflective structure 30. A typical arrangement is a molding process or an injection process. Two pairs of side edges 231 of the edge surface 23 and two pairs of side edges 131 of the edge surface 13 are covered by the reflective structure 30 in this embodiment.

  When fabricating the reflective structure 30 utilizing a molding process, the array of organic electroluminescent structures previously disposed in the mold release layer 50 'can be disposed within the mold (not shown) A resin material for manufacturing the LED chip 30 may be injected into the mold surrounding both the edge surface 23 of the phosphorescent structure 20 and the edge surface 13 of the LED semiconductor die 10. [ The reflective structure 30 is formed after the resin material is cured.

The mold may be omitted if the reflective structure 30 is fabricated utilizing an injection process. A typical injection method is: first, injecting the resin material used to make the reflective structure 30, for example by using a syringe to form an array of organic electroluminescent structures pre-disposed on the release layer 50 ' The resin material is directly injected into the gap in the gap. Secondly, the implantation amount is gradually increased until it substantially completely covers the edge surface 13 of the LED semiconductor die 10 and the edge surface 23 of the phosphorescent structure 20. It is understood that the amount of the reflector resin material is precisely controlled so that the situation that the top surface 21 of the phosphorescent structure 20 is contaminated by the overflowing resin material does not occur. Finally, the reflective structure 30 is formed after the resin material is cured.

The last step disclosed after the formation of the reflective structure 30 is the singulation process. Once the reflective structure 30 is formed, the release layer 50 'may be removed as shown in Figure 8B to secure an array of CSP LED devices 1A. The dicing process is performed by the reflective structure 30 along the first horizontal direction D1 and the second horizontal direction D2 to secure a plurality of CSP LED devices 1A as shown in Figure 8C. Respectively.

The above description details the manufacturing method for manufacturing the embodiment of the CSP LED device 1A according to the present invention. A detailed description of other manufacturing methods for manufacturing other embodiments of the CSP LED is as follows. Some detailed descriptions disclosed in the following manufacturing method are similar to the detailed description of the manufacturing method for the CSP LED device 1A so that they are omitted for brevity purposes.

Figs. 9A-12B illustrate various fabrication steps of the manufacturing method of the CSP LED device 1B embodiment according to the present invention.

The release layer 30 is first prepared and the supernatant liquid-pervious layer 202 and the phosphorescent layer 201 are placed on the release layer 50 using a manufacturing process such as spraying, printing, or molding, do. An alternative approach may be used to first fabricate a phosphorescent sheet, such as the supernatant light-emitting layer 202 and the phosphorescent layer 201. When using this approach, the phosphorescent sheet is placed on the release layer 50 with the phosphorescent layer 201 facing upward.

9B, a plurality of LED semiconductor dies 10 are arranged on the phosphorescent layer 201 as an array so that the upper surface 11 of the LED semiconductor die 10 faces downward, Lt; / RTI > In other words, the electrode set 14 of the LED semiconductor die 10 faces upward. Thus forming an array of oppositely disposed LED semiconductor dies 10 including a specified distance of vertices.

The luminescent sheet is then cut along the first horizontal direction D1 to selectively remove a portion of the supernatant light-transmitting layer 202 and the phosphorescent layer 201 as shown in Figs. 10A to 10C. It is understood that the cutting depth can be adjusted so that the release layer 30 is not cut off. Sectional view along the second horizontal direction D2 as shown in Fig. 10C after singulating and partially removing the supernatant light-emitting layer 202 and the phosphorescent layer 201 results in the phosphorescent structure 20 having an organic Lt; RTI ID = 0.0 > including < / RTI > the electroluminescent structure. And a pair of side edges 231b are exposed. It is preferable that the manufacturing process for selectively removing portions of the photolithographic sheet proceeds before forming the reflective structure. In addition, a cross-sectional view along the first horizontal direction D1 as shown in Fig. 10B shows that the phosphorescent structures 20 are connected to each other. It is possible to remove the LED semiconductor die 10 from the edge face 13 of the LED semiconductor die 10 during the singulation process in order to facilitate the later singulation process and to prevent cutting and damaging the LED semiconductor die 10 through the dicing saw by mistake And maintains a cutting margin of about 1 占 퐉 to about 100 占 퐉. Therefore, the width of the phosphorescent structure 20 is slightly larger than the width of the LED semiconductor die 10 as shown in FIG. 10C.

11A and 11B, the reflective structure 30 is disposed within a groove that covers the edge surface 13 of the LED semiconductor die 10 and the edge surface 23 of the phosphorescent structure 20 . The side edge 231b perpendicular to the second horizontal direction D2 is exposed after singulating and partially removing the supernatant liquid-pervious layer 202 and the phosphorescent layer 201 so that the reflective structure 30 is exposed as shown in FIG. 11B It can be covered adjacent to the side edge 231b as shown in Fig. On the other hand, the side edge 231a perpendicular to the first horizontal direction D1 is not exposed and therefore not covered by the reflective structure 30 as shown in FIG. 11A.

The release layer 50 is removed (not shown) in order to secure a sheet structure comprising the array of CSP LED devices 1B after forming the reflective structure 30 so that the luminous structure of the CSP LED device 1B 20 and the reflecting structure 30 are connected to each other. Then another singulation process is performed to separate the connected phosphorescent structure 20 and the reflective structure 30. As shown in Figs. 12A and 12B, the CSP LED devices 1B are separated from each other after the singulation process. Specifically, the reflective structures 30 connected to each other are cut along the first horizontal direction D1 without cutting the phosphorescent structure 20, while the reflective structures 30 and the phosphorescent structures 20 connected to each other are cut along the first horizontal direction D1, Is cut along the direction D2.

The above is a detailed description of the manufacturing method for the embodiment of the CSP LED device 1B according to the present invention. A detailed description of another manufacturing method of the CSP LED device (1C) embodiment according to the present invention is as follows.

Figures 13 to 18B show the manufacturing steps of the manufacturing method for manufacturing the embodiment of the CSP LED device 1C according to the present invention.

First, as shown in FIG. 13, a plurality of LED semiconductor dies 10 are disposed on the release layer 50 to form an array of LED semiconductor dies 10 that includes a specified distance of vertices. A phosphorescent layer 201 is formed as shown in FIG. 14 to cover the upper surface 11 and the edge surface 13 of the LED semiconductor 10 and cover the exposed area of the release layer 50. More specifically, after forming the phosphorescent layer 201, the upper surface 11 of the LED semiconductor die 10 is covered by the upper portion 205 of the phosphorescent layer 201 and the side edges 13a of the edge surface 13 And 131b are covered by the corner portion 206 of the phosphorescent layer 201 and the exposed area of the release layer 50 is covered by the extension 207 of the phosphorescent layer 201. [ Preferably, the phosphorescent layer 201 may be formed through the method described in US2010 / 0119839.

Next, as shown in FIGS. 15A to 15B, a supernatant liquid-pervious layer 202 is formed and laminated on the phosphorescent layer 201. In such a manufacturing step, a molding process may be utilized to form the supernatant light-emitting layer 202, and a mold containing a plurality of microstructured features on the inner mold surface is optionally included. The morphology of the microstructure on the inner mold surface can move to the outer surface of the microstructure of the microlens array layer as shown in Figure 1F. Thus, the supernatant light-emitting layer 202 'including the microlens array layer can be formed after molding.

16A to 16C, the phosphorescent sheet is cut along the first horizontal direction D1 to selectively remove a portion of the supernatant light-transmitting layer 202 and the phosphorescent layer 201. [ Sectional view including a section along the first horizontal direction D1 as shown in FIG. 16B after singulating and partially removing the supernatant liquid crystal layer 202 and the phosphorescent layer 201 results in the formation of the phosphorescent structures 20, Sectional view including a section along the second horizontal direction D2 as shown in Figure 16C shows that the phosphorescent structure 20 is separated and the two side edges 231b are exposed do.

The reflective structure 30 is then arranged to cover the edge surface 23 of the phosphorescent structure 20, as shown in Figs. 17A and 17B. Since the side edges 231b perpendicular to the second horizontal direction D2 are exposed after selective removal of the supernatant liquid-pervious layer 202 and the phosphorescent layer 201, the reflective structure 30, as shown in Figure 17B, It can be covered adjacent to the side edges 231b. On the other hand, the side edges 231a, which are perpendicular to the first horizontal direction D1 as shown in Fig. 17A, are not covered by the reflective structure 30 since they are not exposed.

After forming the reflective structure 30, the release layer 50 is removed (not shown) to secure a sheet layer comprising a plurality of CSP LED devices 1C and the CSP LED device 1C The phosphorescent structure 20 and the reflective structure 30 of the photonic crystal 20 are still connected to each other. A singulation process is then performed to separate the connected phosphorescent structure 20 and the reflective structure 30. After singulation, the CSP LED devices 1C are separated from each other as shown in Figs. 18A and 18B. Specifically, the reflective structures 30 connecting to each other are singulated along the first horizontal direction D1 without singulating the phosphorescent structure 20, while the reflective structures 30 and the phosphorescent structures 20 connected to each other And is singulated along the second horizontal direction D2.

Further, the manufacturing procedure for manufacturing the CSP LED device 1D and the corresponding CSP LED device shown in Figs. 4A to 4D is as follows. In the embodiment of the manufacturing method shown in Figs. 13 to 18B according to the present invention, the array of LED semiconductor dies 10 is first arranged as shown in Fig. The light scattering particles are then dispersed in a substantially transparent resin material to form a reflective resin material and to remove the oxtane, xylene, acetate, ether ether, toluene, and the like. The diluted reflective resin material having a relatively low viscosity can be coated on the surface of the array of LED semiconductor dies 10 and the open area of the release layer 50 utilizing a manufacturing process such as spraying. Most of the diluted reflective resin material flows by gravity from a higher position (e.g., the upper surface of the semiconductor die 10) to a lower position (e.g., the open area of the release layer 50) Is uniformly distributed at the open area of the release layer (50). After the thermal curing process, the reflective underlayer 40 may be formed as shown in Figures 4A-4D. Then, the CSP LED device 1D according to the present invention can be manufactured through the manufacturing steps shown in Figs. 14 to 18B.

Alternatively, the sub-reflecting layer 40 may also be formed through a dosing process method. Specifically, when a relatively small amount of reflective resin material is injected into the grooves of the array of LED semiconductor dies 10 pre-disposed on top of the release layer 50, the reflective resin material is evenly distributed due to the gravitational effect, 50). Therefore, the reflection lower layer 40 is formed after the reflection resin material is cured.

Various embodiments of the fabrication method according to the above disclosure are disclosed for making various CSP LED devices to define a viewing angle in at least one specific horizontal direction, thus providing an overall asymmetrical roughness radiation pattern. The published method is well suited for utilizing a series of mass production processes.

While the invention has been described in terms of specific embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention as defined by the appended claims. The objects, objects, and scope of the present invention may be modified in various ways to suit particular situations, materials, compositions of matter, methods, or processes. In particular, it should be understood that although the methods disclosed herein have been described with reference to particular acts performed in a particular order, such acts may be combined, subdivided, or rearranged unless departing from the teachings of the present invention. Accordingly, the order and classification of operations are not limited to the present invention unless specifically described herein.

Claims (49)

A first edge surface, a first edge surface, a first edge surface, a first edge surface, a first edge surface, and a second edge surface, the first edge surface extending between the first upper surface and the first lower surface, The electrode set comprising: a flip chip light emitting diode (LED) semiconductor die disposed on the first lower surface;
A second top surface, a second bottom surface located opposite the second top surface, and a second edge surface extending between the second top surface and the second bottom surface, the surface area of the second top surface being greater than the surface area of the second bottom surface Wherein the second bottom surface covers the first upper surface of the LED semiconductor die and has a phosphorescent layer and a supernatant light-transmitting layer disposed in the phosphorescent layer; And
And a reflective structure covering a first edge surface of the LED semiconductor die and a second edge surface of the phosphorescent structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are specified along the length and width of the light emitting device,
Wherein two pairs of side edges of the first edge surface of the LED semiconductor die are covered by the reflective structure and a pair of side edges of the LED semiconductor die are perpendicular to the first horizontal direction, The other pair of side edges being perpendicular to the second horizontal direction;
Wherein two pairs of side edges of the second edge surface of the phosphorescent structure are covered by the reflective structure, a pair of side edges of the phosphorescent structure are inclined with respect to the first horizontal direction, And the pair of side edges are perpendicular to the second horizontal direction.
delete delete The method according to claim 1,
Wherein the supercritical fluid light-emitting layer of the phosphorescent structure further comprises a microlens array layer.
The method according to claim 1,
Wherein the phosphorescent layer further comprises another translucent layer disposed below the phosphorescent layer.
The method according to claim 1,
Further comprising a submount substrate,
Wherein the LED semiconductor die is electrically connected to the submount substrate.
The method according to claim 1,
Wherein the reflective structure comprises at least a light transmitting resin material and light scattering particles.
8. The method of claim 7,
Wherein the light transmitting resin material comprises at least one of polyphthalamide, polycyclohexylenedimethylene terephthalate, epoxy resin composition, or silicone resin; Wherein the light scattering particles comprise at least one of titanium dioxide, boron nitride, silicon dioxide or aluminum oxide.
A first edge surface, a first edge surface, a first edge surface, a first edge surface, a first edge surface, and a second edge surface, the first edge surface extending between the first upper surface and the first lower surface, The electrode set comprising: a flip chip light emitting diode (LED) semiconductor die disposed on the first lower surface;
A second top surface, a second bottom surface located opposite the second top surface, and a second edge surface extending between the second top surface and the second bottom surface, wherein the surface area of the second bottom surface is greater than the surface area of the LED semiconductor die A phosphorescent structure that is larger than the surface area of the first upper surface, the second lower surface covers the first upper surface of the LED semiconductor die, and includes a phosphorescent layer and a supercritical liquid crystal transparent layer disposed on the phosphorescent layer; And
And a reflective structure covering the first edge surface of the LED semiconductor die and partially covering the second edge surface of the phosphorescent structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are specified along the length and width of the light emitting device,
Wherein the first edge surface of the LED semiconductor die comprises two pairs of side edges covered by the reflective structure and wherein a pair of side edges of the LED semiconductor die are perpendicular to the first horizontal direction, The side edges of the other pair of die are perpendicular to the second horizontal direction,
Wherein the second edge surface of the phosphorescent structure comprises two pairs of side edges and a pair of side edges of the phosphorescent structure perpendicular to the second horizontal direction are covered by the reflective structure, Wherein the other pair of side edges of the phosphorescent structure at right angles to the reflective surface are not covered by the reflective structure.
delete delete 10. The method of claim 9,
Wherein the supercritical fluid light-emitting layer of the phosphorescent structure further comprises a microlens array layer.
10. The method of claim 9,
Wherein the phosphorescent layer further comprises another translucent layer disposed below the phosphorescent layer.
10. The method of claim 9,
Further comprising a submount substrate,
Wherein the LED semiconductor die is electrically connected to the submount substrate.
10. The method of claim 9,
Wherein the reflective structure comprises at least a light transmitting resin material and light scattering particles.
16. The method of claim 15,
Wherein the light transmitting resin material comprises at least one of polyphthalamide, polycyclohexylenedimethylene terephthalate, epoxy resin composition, or silicone resin; Wherein the light scattering particles comprise at least one of titanium dioxide, boron nitride, silicon dioxide or aluminum oxide.
A first edge surface, a first edge surface, a first edge surface, a first edge surface, a first edge surface, and a second edge surface, the first edge surface extending between the first upper surface and the first lower surface, The electrode set comprising: a flip chip light emitting diode (LED) semiconductor die disposed on the first lower surface;
A second top surface, a second bottom surface located opposite the second top surface, and a second edge surface extending between the second top surface and the second bottom surface, wherein the first top surface and the first edge of the LED semiconductor die A phosphorescent layer covering the surface and comprising a phosphorescent layer and a supercritical fluid-filled layer disposed on the phosphorescent layer; And
And a reflective structure partially covering the second edge surface of the phosphorescent structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are specified along the length and width of the light emitting device,
Wherein two pairs of side edges of the first edge surface of the LED semiconductor die are covered by the phosphorescent structure and a pair of side edges of the LED semiconductor die are perpendicular to the first horizontal direction, The other side edge of the pair is perpendicular to the second horizontal direction; And
Wherein the second edge surface of the phosphorescent structure comprises two pairs of side edges and a pair of side edges of the phosphorescent structure perpendicular to the second horizontal direction are covered by the reflective structure, Wherein the other pair of side edges of the phosphorescent structure at right angles to the reflective surface are not covered by the reflective structure.
delete delete 18. The method of claim 17,
Further comprising a reflection lower layer disposed below the phosphorescent structure,
Characterized in that the under-reflective layer comprises at least a light-transmitting resin material and light-scattering particles, and the under-reflective layer is adjacent to a second lower surface of the phosphorescent structure and covers at least a part of the first edge surface of the LED semiconductor die Emitting device.
18. The method of claim 17,
The phosphorescent layer of the phosphorescent structure includes an upper portion covering the first upper surface of the LED semiconductor die, an edge portion covering the first edge surface of the LED semiconductor die, and an extension extending outward from the edge portion of the phosphorescent layer Emitting device.
18. The method of claim 17,
Wherein the supercritical fluid light-emitting layer of the phosphorescent structure further comprises a microlens array layer.
18. The method of claim 17,
Wherein the phosphorescent layer further comprises another translucent layer disposed below the phosphorescent layer.
18. The method of claim 17,
Further comprising a submount substrate,
Wherein the LED semiconductor die is electrically connected to the submount substrate.
18. The method of claim 17,
Wherein the reflective structure comprises at least a light transmitting resin material and light scattering particles.
26. The method of claim 25,
Wherein the light transmitting resin material comprises at least one of polyphthalamide, polycyclohexylenedimethylene terephthalate, epoxy resin composition, or silicone resin; Wherein the light scattering particles comprise at least one of titanium dioxide, boron nitride, silicon dioxide or aluminum oxide.
A first edge surface, a first edge surface, a first edge surface, a first edge surface, a first edge surface, and a second edge surface, the first edge surface extending between the first upper surface and the first lower surface, The electrode set comprising: a flip chip light emitting diode (LED) semiconductor die disposed on the first lower surface;
A second top surface, a second bottom surface located opposite the second top surface, and a second edge surface extending between the second top surface and the second bottom surface, the first top surface of the LED semiconductor die, A phosphorescent structure partially covering the first edge surface of the LED semiconductor die and including a phosphorescent layer and a supercritical fluid-filled layer disposed on the phosphorescent layer; And
A reflective structure partially covering the first edge surface of the LED semiconductor die and partially covering the second edge surface of the phosphorescent structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are specified along the length and width of the light emitting device,
Wherein a first edge surface of the LED semiconductor die comprises two pairs of side edges and a pair of side edges of the LED semiconductor die perpendicular to the first horizontal direction are covered by the phosphorescent structure, The other pair of side edges of the LED semiconductor die being perpendicular to the horizontal direction are covered by the reflective structure; And
Wherein the second edge surface of the phosphorescent structure comprises two pairs of side edges and a pair of side edges of the phosphorescent structure perpendicular to the second horizontal direction are covered by the reflective structure, Wherein the other pair of side edges of the phosphorescent structure at right angles to the reflective surface are not covered by the reflective structure.
delete delete 28. The method of claim 27,
Wherein the phosphorescent layer of the phosphorescent structure comprises an upper portion covering the first upper surface of the LED semiconductor die, an edge portion partially covering the first edge surface of the LED semiconductor die, and an extension extending outward at the edge portion of the phosphorescent layer And a light emitting device.
28. The method of claim 27,
Wherein the supercritical fluid light-emitting layer of the phosphorescent structure further comprises a microlens array layer.
28. The method of claim 27,
Further comprising a submount substrate,
Wherein the LED semiconductor die is electrically connected to the submount substrate.
28. The method of claim 27,
Wherein the phosphorescent layer further comprises another translucent layer disposed below the phosphorescent layer.
28. The method of claim 27,
Wherein the reflective structure comprises at least a light transmitting resin material and light scattering particles.
35. The method of claim 34,
Wherein the light transmitting resin material comprises at least one of polyphthalamide, polycyclohexylenedimethylene terephthalate, epoxy resin composition, or silicone resin; Wherein the light scattering particles comprise at least one of titanium dioxide, boron nitride, silicon dioxide or aluminum oxide.
Disposing a phosphorescent structure comprising a phosphorescent layer and a supernatant light-transmissive layer in an LED semiconductor die, the phosphorescent layer being between the supernatant light-emitting layer and a first top surface of the LED semiconductor die; And
Covering at least a portion of the second edge surface of the phosphorescent structure and at least a portion of the first edge surface of the LED semiconductor die with a reflective structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are each specified along the length and width of the light emitting device,
Wherein the second edge surface of the phosphorescent structure comprises four side edges and the step of disposing the phosphorescent structure in the LED semiconductor die comprises:
Wherein a pair of side edges of the four side edges of the phosphorescent structure is inclined with respect to the first horizontal direction and the other side edge of the four side edges of the phosphorescent structure is perpendicular to the second horizontal direction, Forming a second edge surface of the phosphorescent structure so that the second edge surface is formed; And
Further comprising disposing the phosphorescent structure to attach to a first top surface of the LED semiconductor die.
37. The method of claim 36,
Wherein the second edge surface of the phosphorescent structure is formed by punching, molding or sawing.
37. The method of claim 36,
Wherein the step of covering the second edge surface of the phosphorescent structure with the reflective structure comprises:
Covering the four side edges of the phosphorescent structure with the reflective structure; And
Further comprising the step of singulating the reflective structure to form the light emitting device.
Disposing a phosphorescent structure comprising a phosphorescent layer and a supernatant light-transmissive layer in an LED semiconductor die, the phosphorescent layer being between the supernatant light-emitting layer and a first top surface of the LED semiconductor die; And
Covering at least a portion of the second edge surface of the phosphorescent structure and at least a portion of the first edge surface of the LED semiconductor die with a reflective structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are each specified along the length and width of the light emitting device,
Wherein the step of disposing the phosphorescent structure in the LED semiconductor die comprises:
Disposing the LED semiconductor die in the phosphorescent structure with the electrode set of the LED semiconductor die facing upward; And
Further comprising cutting the phosphorescent structure and selectively removing a portion of the phosphorescent structure along the first horizontal direction.
40. The method of claim 39,
Wherein the second edge surface of the phosphorescent structure comprises two pairs of side edges and the step of covering the second edge surface of the phosphorescent structure comprises:
Covering the pair of side edges of the phosphorescent structure at right angles to the second horizontal direction with the reflective structure facing each other; And
Further comprising the step of exposing another pair of side edges of the phosphorescent structure perpendicular to the first horizontal direction without covering the reflective structure with the reflective structure while facing each other.
40. The method of claim 39,
Singulating the reflective structure along the first horizontal direction; And
Further comprising the step of singulating the phosphorescent structure and the reflective structure along the second horizontal direction.
Disposing a phosphorescent structure comprising a phosphorescent layer and a supernatant light-transmissive layer in an LED semiconductor die, the phosphorescent layer being between the supernatant light-emitting layer and a first top surface of the LED semiconductor die; And
Covering at least a portion of the second edge surface of the phosphorescent structure and at least a portion of the first edge surface of the LED semiconductor die with a reflective structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are each specified along the length and width of the light emitting device,
Wherein the step of disposing the phosphorescent structure in the LED semiconductor die comprises:
Forming the phosphorescent layer on a first upper surface and a first peripheral surface of the LED semiconductor die;
Forming the supernatant light-transmitting layer on the phosphorescent layer to form the phosphorescent structure; And
And cutting the phosphorescent structure along the first horizontal direction.
43. The method of claim 42,
Wherein the second edge surface of the phosphorescent structure comprises two pairs of side edges and the step of covering the second edge surface of the phosphorescent structure comprises:
Covering the pair of side edges of the phosphorescent structure at right angles to the second horizontal direction by the reflective structure facing each other; And
Further comprising the step of exposing the other pair of side edges of the phosphorescent structure orthogonal to the first horizontal direction in a state not covered by the reflective structure facing each other.
43. The method of claim 42,
Singulating the reflective structure along the first horizontal direction; And
Further comprising the step of singulating the phosphorescent structure and the reflective structure along the second horizontal direction.
43. The method of claim 42,
Wherein forming the phosphorescent layer on the first upper surface and the first edge surface of the LED semiconductor die comprises:
Forming a reflective underlayer covering at least a portion of the first edge surface of the LED semiconductor die; And
And forming the phosphorescent layer on the reflection lower layer. A first edge surface, a first edge surface, a first edge surface, a first edge surface, a first edge surface, and a second edge surface, the first edge surface extending between the first upper surface and the first lower surface, The electrode set comprising: a flip chip light emitting diode (LED) semiconductor die disposed on the first lower surface;
A second top surface, a second bottom surface located opposite the second top surface, and a second edge surface extending between the second top surface and the second bottom surface, the surface area of the second top surface being greater than the surface area of the second bottom surface Wherein the second bottom surface covers the first top surface of the LED semiconductor die and includes an optical transparent material associated with the spectrum emitted from the LED semiconductor die; And
And a reflective structure covering the first edge surface of the LED semiconductor die and the second edge surface of the light-transmitting structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are specified along the length and width of the light emitting device,
Wherein two pairs of side edges of the first edge surface of the LED semiconductor die are covered by the reflective structure and a pair of side edges of the LED semiconductor die are perpendicular to the first horizontal direction, The other pair of side edges being perpendicular to the second horizontal direction;
Wherein two pairs of side edges of the second edge surface of the light-transmitting structure are covered by the reflecting structure, a pair of side edges of the light-transmitting structure are inclined with respect to the first horizontal direction, And the pair of side edges are perpendicular to the second horizontal direction.
A first edge surface, a first edge surface, a first edge surface, a first edge surface, a first edge surface, and a second edge surface, the first edge surface extending between the first upper surface and the first lower surface, The electrode set comprising: a flip chip light emitting diode (LED) semiconductor die disposed on the first lower surface;
A second top surface, a second bottom surface located opposite the second top surface, and a second edge surface extending between the second top surface and the second bottom surface, wherein the surface area of the second bottom surface is greater than the surface area of the LED semiconductor die A light transmitting structure including an optical transparent material that is larger than a surface area of the first upper surface, the second lower surface covers a first upper surface of the LED semiconductor die and is related to a spectrum emitted from the LED semiconductor die; And
And a reflective structure covering the first edge surface of the LED semiconductor die and partially covering the second edge surface of the light emitting structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are specified along the length and width of the light emitting device,
Wherein the first edge surface of the LED semiconductor die comprises two pairs of side edges covered by the reflective structure and wherein a pair of side edges of the LED semiconductor die are perpendicular to the first horizontal direction, The side edges of the other pair of die are perpendicular to the second horizontal direction,
Wherein the second edge surface of the light-transmitting structure includes two pairs of side edges, a pair of side edges of the light-transmitting structure perpendicular to the second horizontal direction are covered by the reflective structure, And the other pair of side edges of the light-transmitting structure perpendicular to the light-emitting structure are not covered by the reflective structure.
A first edge surface, a first edge surface, a first edge surface, a first edge surface, a first edge surface, and a second edge surface, the first edge surface extending between the first upper surface and the first lower surface, The electrode set comprising: a flip chip light emitting diode (LED) semiconductor die disposed on the first lower surface;
A second top surface, a second bottom surface located opposite the second top surface, and a second edge surface extending between the second top surface and the second bottom surface, wherein the first top surface and the first edge of the LED semiconductor die A light-emitting structure covering the surface and comprising an optical transparent material associated with the spectrum emitted from the LED semiconductor die; And
And a reflective structure partially covering the second edge surface of the light-transmitting structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are specified along the length and width of the light emitting device,
Wherein two pairs of side edges of the first edge surface of the LED semiconductor die are covered by the light emitting structure, a pair of side edges of the LED semiconductor die are perpendicular to the first horizontal direction, The other side edge of the pair is perpendicular to the second horizontal direction; And
Wherein the second edge surface of the light-transmitting structure includes two pairs of side edges, a pair of side edges of the light-transmitting structure perpendicular to the second horizontal direction are covered by the reflective structure, And the other pair of side edges of the light-transmitting structure perpendicular to the light-emitting structure are not covered by the reflective structure.
A first edge surface, a first edge surface, a first edge surface, a first edge surface, a first edge surface, and a second edge surface, the first edge surface extending between the first upper surface and the first lower surface, The electrode set comprising: a flip chip light emitting diode (LED) semiconductor die disposed on the first lower surface;
A second top surface, a second bottom surface located opposite the second top surface, and a second edge surface extending between the second top surface and the second bottom surface, the first top surface of the LED semiconductor die, A light-transmitting structure partially covering the first edge surface of the LED semiconductor die and including an optical transparent material associated with a spectrum emitted from the LED semiconductor die; And
A reflective structure partially covering the first edge surface of the LED semiconductor die and partially covering the second edge surface of the light-transmitting structure,
The first horizontal direction and the second horizontal direction perpendicular to the first horizontal direction are specified along the length and width of the light emitting device,
Wherein a first edge surface of the LED semiconductor die comprises two pairs of side edges and a pair of side edges of the LED semiconductor die perpendicular to the first horizontal direction are covered by the light projecting structure, The other pair of side edges of the LED semiconductor die being perpendicular to the horizontal direction are covered by the reflective structure; And
Wherein the second edge surface of the light-transmitting structure includes two pairs of side edges, a pair of side edges of the light-transmitting structure perpendicular to the second horizontal direction are covered by the reflective structure, And the other pair of side edges of the light-transmitting structure perpendicular to the light-emitting structure are not covered by the reflective structure.

Images