Patent Application
20250048807
Embodiments of the invention relate generally to a light emitting diode package.
A light emitting diode emits light having various wavelengths through recombination of holes and electrons in a junction region of p-type and n-type semiconductors upon application of electric current thereto. Due to various advantages, such as longer lifespan, lower power consumption, and better operation characteristics than filaments used in a conventional light emitting apparatus, there is increasing demand for light emitting diodes.
A light emitting diode package adopting the light emitting diode is used as a light source in various fields, such as a backlight unit of a display device and the like.
The light emitting diode package employs a light transmissive resin covering a light emitting diode chip in order to protect the light emitting diode chip. Alternatively, the light emitting diode package may employ a light transmissive resin including a wavelength conversion material dispersed therein in order to convert wavelengths of light emitted from the light emitting diode chip.
In general, an epoxy resin or a silicone resin is used as the light transmissive resin. However, the light transmissive resin has a higher coefficient of thermal expansion than the light emitting diode chip.
Accordingly, the light transmissive resin undergoes significant expansion or contraction due to temperature variation of the light emitting diode chip or for other reasons. Since there is a significant difference in the degree of contraction or expansion due to temperature variation between the light emitting diode chip and the light transmissive resin, cracks may be generated in the light transmissive resin. When the cracks are generated in the light transmissive resin, the light emitting diode package and a display device including the light emitting diode package may suffer from deterioration in reliability.
The above information disclosed in this Background section is only for understanding of the background of the inventive concepts, and, therefore, it may contain information that does not constitute prior art.
Embodiments of the present disclosure provide a light emitting diode package that has improved reliability by preventing generation of cracks. Embodiments of the present disclosure provide a light emitting diode package that minimizes deterioration in luminous efficacy while improving reliability.
In accordance with embodiments of the present disclosure, a light emitting diode package includes a light emitting diode chip emitting light and a light transmissive member. The light transmissive member covers at least an upper surface of the light emitting diode chip and includes a light transmissive resin and reinforcing fillers. The reinforcing fillers have at least two side surfaces having different lengths and are dispersed in the light transmissive resin.
According to other embodiments of the present disclosure, a light emitting diode package employs reinforcing fillers having a low coefficient of thermal expansion to prevent cracking in a light transmissive resin while improving reliability.
According to further other embodiments of the present disclosure, the light emitting diode package employs light transmissive reinforcing fillers to improve reliability while minimizing deterioration in luminous efficacy.
It is to be understood that both the foregoing general description and the following detailed description are illustrative and explanatory and are intended to provide further explanation of the invention as claimed.
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the inventive concepts.
In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various embodiments or implementations of the invention. As used herein “embodiments” and “implementations” are interchangeable words that are non-limiting examples of devices or methods employing one or more of the inventive concepts disclosed herein. It is apparent, however, that various embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring various embodiments. Further, various embodiments may be different, but do not have to be exclusive. For example, specific shapes, configurations, and characteristics of an embodiment may be used or implemented in another embodiment without departing from the inventive concepts.
Unless otherwise specified, the illustrated embodiments are to be understood as providing features of varying detail of some ways in which the inventive concepts may be implemented in practice. Therefore, unless otherwise specified, the features, components, modules, layers, films, panels, regions, and/or aspects, etc. (hereinafter individually or collectively referred to as “elements”), of the various embodiments may be otherwise combined, separated, interchanged, and/or rearranged without departing from the inventive concepts.
The use of cross-hatching and/or shading in the accompanying drawings is generally provided to clarify boundaries between adjacent elements. As such, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for particular materials, material properties, dimensions, proportions, commonalities between illustrated elements, and/or any other characteristic, attribute, property, etc., of the elements, unless specified. Further, in the accompanying drawings, the size and relative sizes of elements may be exaggerated for clarity and/or descriptive purposes. When an embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. Also, like reference numerals denote like elements.
When an element, such as a layer, is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it may be directly on, connected to, or coupled to the other element or layer or intervening elements or layers may be present. When, however, an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. To this end, the term “connected” may refer to physical, electrical, and/or fluid connection, with or without intervening elements. Further, the D1-axis, the D2-axis, and the D3-axis are not limited to three axes of a rectangular coordinate system, such as the x, y, and z-axes, and may be interpreted in a broader sense. For example, the D1-axis, the D2-axis, and the D3-axis may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms “first,” “second,” etc. may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. Thus, a first element discussed below could be termed a second element without departing from the teachings of the disclosure.
Spatially relative terms, such as “beneath,” “below,” “under,” “lower,” “above,”
“upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), and the like, may be used herein for descriptive purposes, and, thereby, to describe one elements relationship to another element(s) as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of an apparatus in use, operation, and/or manufacture in addition to the orientation depicted in the drawings. For example, if the apparatus in the drawings is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and, as such, the spatially relative descriptors used herein interpreted accordingly.
The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms, “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Moreover, the terms “comprises,” “comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It is also noted that, as used herein, the terms “substantially,” “about,” and other similar terms, are used as terms of approximation and not as terms of degree, and, as such, are utilized to account for inherent deviations in measured, calculated, and/or provided values that would be recognized by one of ordinary skill in the art.
Various embodiments are described herein with reference to sectional and/or exploded illustrations that are schematic illustrations of idealized embodiments and/or intermediate structures. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments disclosed herein should not necessarily be construed as limited to the particular illustrated shapes of regions, but are to include deviations in shapes that result from, for instance, manufacturing. In this manner, regions illustrated in the drawings may be schematic in nature and the shapes of these regions may not reflect actual shapes of regions of a device and, as such, are not necessarily intended to be limiting.
As customary in the field, some embodiments are described and illustrated in the accompanying drawings in terms of functional blocks, units, and/or modules. Those skilled in the art will appreciate that these blocks, units, and/or modules are physically implemented by electronic (or optical) circuits, such as logic circuits, discrete components, microprocessors, hard-wired circuits, memory elements, wiring connections, and the like, which may be formed using semiconductor-based fabrication techniques or other manufacturing technologies. In the case of the blocks, units, and/or modules being implemented by microprocessors or other similar hardware, they may be programmed and controlled using software (e.g., microcode) to perform various functions discussed herein and may optionally be driven by firmware and/or software. It is also contemplated that each block, unit, and/or module may be implemented by dedicated hardware, or as a combination of dedicated hardware to perform some functions and a processor (e.g., one or more programmed microprocessors and associated circuitry) to perform other functions. Also, each block, unit, and/or module of some embodiments may be physically separated into two or more interacting and discrete blocks, units, and/or modules without departing from the scope of the inventive concepts. Further, the blocks, units, and/or modules of some embodiments may be physically combined into more complex blocks, units, and/or modules without departing from the scope of the inventive concepts.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure is a part. Terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein.
In accordance with embodiments of the present disclosure, a light emitting diode package includes: a light emitting diode chip emitting light and a light transmissive member. The light transmissive member covers at least an upper surface of the light emitting diode chip and includes a light transmissive resin and reinforcing fillers. The reinforcing fillers have at least two side surfaces having different lengths and are dispersed in the light transmissive resin.
In some embodiments, the reinforcing fillers may include one selected from the group of glass fibers formed of Si, Al, Fe, Ba, Ca, Mg and Na.
In other embodiments, the reinforcing fillers may include glass fibers formed of SiO2, Al2O3, MgO, CaO, Na2O, K2O, or B2O3.
The reinforcing fillers may be present in an amount of 10% by weight (wt %) to 200 wt % relative to the light transmissive resin.
The reinforcing fillers may be present in an amount of 50 wt % to 100 wt % relative to the light transmissive resin.
According to one embodiment, the light transmissive member may cover upper and side surfaces of the light emitting diode chip.
The light emitting diode package may further include a barrier member covering a side surface of the light transmissive member and reflecting light emitted through the side surface of the light emitting diode chip.
The barrier member may further include the reinforcing fillers.
According to another embodiment, the light transmissive member may cover an upper surface of the light emitting diode chip.
The light emitting diode package may further include a barrier member covering a side surface of the light emitting diode chip.
The barrier member may further include the reinforcing fillers.
The light transmissive member may further cover an upper surface of the barrier member.
The barrier member may further cover a side surface of the light transmissive member.
The light transmissive member may further include a wavelength conversion material dispersed in the light transmissive resin.
Hereinafter, light emitting diode packages according to embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.
The light emitting diode package 100 according to the first embodiment includes a light emitting diode chip 110 and a light transmissive member 120.
In some embodiments, the light emitting diode chip 110 includes a GaN-based semiconductor stack grown on a growth substrate for growth of semiconductor layers. The light emitting diode chip 110 emits UV light or visible light.
The light emitting diode chip 110 may include electrodes (not shown) on at least one of upper and lower portions thereof. For example, the electrodes may be formed at the upper portion of the light emitting diode chip 110 to be electrically connected to an external component by wire bonding. Alternatively, the electrodes may be formed at the lower portion of the light emitting diode chip 110 to be electrically connected to an external component by flip chip bonding. Further alternatively, the electrodes of the light emitting diode chip 110 may be formed at the upper and lower portions thereof, respectively, in which the electrode formed at the lower portion of the light emitting diode chip 110 is electrically connected to the external component by flip chip bonding and the electrode formed at the upper portion thereof is electrically connected to the external component by wire bonding.
The light transmissive member 120 covers a light emitting surface of the light emitting diode chip 110. For example, the light transmissive member 120 covers upper and side surfaces of the light emitting diode chip 110. With this structure, the light transmissive member 120 can protect the light emitting diode chip 110 from an external environment.
In some embodiments, the transmissive member 120 may be formed such that a portion covering the side surfaces of the light emitting diode chip 110 is thicker than a portion covering the upper surface of the light emitting diode chip 110. That is, a thickness D1 from the side surface of the light emitting diode chip 110 to the side surface of the transmissive member 120 is thicker than a thickness D2 from the upper surface of the light emitting diode chip 110 to the upper surface of the transmissive member 120.
The light transmissive member 120 includes a light transmissive resin 121, reinforcing fillers 122, and a wavelength conversion material 123. The reinforcing fillers 122 and the wavelength conversion material 123 are formed of light transmissive materials and dispersed in the light transmissive resin 121. If non-transmissive materials, such as typical metal fillers or carbon fillers, are dispersed in the light transmissive resin 121, luminous efficacy of the light emitting diode package can be deteriorated. Thus, the light emitting diode package 100 according to this embodiment can prevent or minimize deterioration in luminous efficacy using the reinforcing fillers 122, which are light transmissive.
For example, the light transmissive resin 121 may include one selected from the group of a silicone resin, an epoxy resin, and a polyimide resin. However, it should be understood that these materials are provided by way of example and the materials for the light transmissive resin 121 are not limited thereto. The light transmissive resin 121 may be a resin selected from any materials that allow transmission of light therethrough.
In some embodiments, the light transmissive resin 121 may have a higher coefficient of thermal expansion than the light emitting diode chip 110. Further, since the light transmissive resin 121 contacts the light emitting diode chip 110, light and heat emitted from the light emitting diode chip 110 are directly transferred to the light transmissive resin 121.
Accordingly, in a conventional light emitting diode package, the light transmissive resin is degraded by light and heat emitted from the light emitting diode chip and suffers from cracking. Reliability of the light emitting diode package is deteriorated due to intrusion of foreign matter, such as moisture, air, dust, and the like, into the light emitting diode package through cracks or due to discharge of light not subjected to wavelength conversion through the cracks.
Unlike the conventional light emitting diode package, the light emitting diode package 100 according to this embodiment includes the reinforcing fillers 122 dispersed in the light transmissive resin 121. The reinforcing fillers 122 prevent deterioration in reliability of the light emitting diode package due to difference in coefficient of thermal expansion between the light transmissive resin 121 and the light emitting diode chip 110.
The reinforcing fillers 122 has at least two side surfaces having different lengths. For example, the reinforcing fillers 122 may have an elongated rod structure having a major axis and a minor axis, as illustrated in
The reinforcing fillers 122 may include one selected from the group of glass fibers formed of Si, Al, Fe, Ba, Ca, Mg and Na. For example, the reinforcing fillers 122 may include one selected from the group of glass fibers formed of SiO2, Al2O3, MgO, CaO, Na2O, K2O and B2O3.
In the light transmissive member 120, the reinforcing fillers 122 may be present in an amount of 10 wt % to 200 wt % relative to the light transmissive resin 121. Alternatively, in the light transmissive member 120, the reinforcing fillers 122 may be present in an amount of 50 wt % to 100 wt % relative to the light transmissive resin 121.
Glass fibers are resistant to heat and have a low coefficient of thermal expansion. In addition, the glass fibers are not affected by light and have good chemical resistance. Thus, the reinforcing fillers 122 formed of the glass fibers also have a low coefficient of thermal coefficient and exhibit good properties in terms of heat resistance and chemical resistance.
Since the reinforcing fillers 122 have a low coefficient of thermal expansion, it is possible to reduce the degree of expansion or contraction of the light transmissive resin 121 due to temperature variation. Accordingly, the reinforcing fillers 122 can prevent generation of cracks in the light transmissive resin 121. Further, the reinforcing fillers 122 can prevent foreign matter from entering the light transmissive resin 121 through cracks by preventing cracking of the light transmissive resin 121.
Further, since the reinforcing fillers 122 have an elongated rod structure, the reinforcing fillers 122 block a progression route of the cracks to prevent progression of the cracks. Furthermore, the reinforcing fillers 122 having an elongated rod structure can obstruct foreign matter from entering the light transmissive resin 121. Furthermore, even when foreign matter enters the light transmissive resin 121, the elongated rod structure of the reinforcing fillers 122 extends an infiltration route of the foreign matter.
As such, the light emitting diode package 100 according to this embodiment includes the reinforcing fillers 122 to improve heat resistance and chemical resistance of the light transmissive member 120, thereby improving reliability.
The wavelength conversion material 123 converts wavelengths of light emitted from the light emitting diode chip 110 such that the light emitting diode package 100 can emit light having a predetermined color. For example, the wavelength conversion material 123 may include phosphors or quantum dots (QD).
Although the light transmissive member 120 is illustrated as including the wavelength conversion material 123 in this embodiment, it should be understood that the light transmissive member 120 is not required to include the wavelength conversion material 123. If light emitted from the light emitting diode package 100 has the same wavelength band as light emitted from the light emitting diode chip 110, the wavelength conversion material 123 can be omitted.
When the light transmissive member 120 is not required to convert the wavelengths of light emitted from the light emitting diode chip 110, the light transmissive member 120 may not include the wavelength conversion material 123.
A first experimental group and a second experimental group are conventional light emitting diode packages 10, 20, respectively.
Referring to
Referring to
Tables 1 and 2, which will be described below, show experimental results comparing reliability of conventional light emitting diode packages 10, 20 (shown in
In the light emitting diode package 100 according to this embodiment, the light transmissive member 120 includes the light transmissive resin 121, the wavelength conversion material 123, and the reinforcing fillers 122. The light transmissive member 120 is also included in the third to seventh experimental groups. The reinforcing fillers 122 have an elongated rod structure, as shown in
The reinforcing fillers 122 are present in an amount of 5 wt % in the third experimental group, in an amount of 10 wt % in the fourth experimental group, in an amount of 50 wt % in the fifth experimental group, in an amount of 100 wt % in the sixth experimental group, and in an amount of 150 wt % in the seventh experimental group.
Table 1 shows experimental results comparing points of times at which cracks are generated in the light transmissive members 11, 21 of the conventional light emitting diode packages 10, 20 and the light transmissive member 120 of the light emitting diode package 100 according to this embodiment.
The experiment was performed while supplying an electric current of 1,000 mA to the light emitting diode chip 110 at 100° C. in each of the experimental groups.
Referring to Table 1, in all of the first experimental group, the second experimental group and the third experimental group, cracks were generated in the light transmissive members 11, 21, 120 when the experiment was performed for 1,000 hours. From this result, it can be seen that the general fillers 22 not having an elongated rod shape failed to prevent cracking of the light transmissive member 21 and to improve reliability of the light emitting diode package 20. Further, it can be seen that the light emitting diode package containing 5 wt % or less of the reinforcing fillers 122 did not exhibit a significant difference in reliability with the conventional light emitting diode packages.
However, in all of the fourth to seventh experimental groups, cracks were generated when the experiment was performed for 1,500 hours or more. Accordingly, it can be seen that the light emitting diode package 100 including the light transmissive member 120 containing 10 wt % or more of the reinforcing fillers 122 had better reliability than the conventional light emitting diode packages 10, 20.
Further, in the fifth experimental group, cracks were generated when the experiment was performed for 2,500 hours, indicating a significant difference from the fourth experimental group in which cracks were generated when the experiment was performed for 1,500 hours. Further, in the sixth and seventh experimental groups, cracks were generated when the experiment was performed for 3,500 hours, indicating a significant difference from the fifth experimental group in which cracks were generated when the experiment was performed for 2,500 hours.
It should be noted that, when the content of the reinforcing fillers 122 exceeds 200 wt %, it is difficult to apply the reinforcing fillers 122 to experiments and packages due to increase in viscosity of the light transmissive member, which makes it difficult to form the light transmissive member.
From these experiments, it can be seen that reliability of the light emitting diode package 100 is improved when the reinforcing fillers 122 are present in an amount of 10 wt % to 200 wt % in the light transmissive member 120. In addition, in some embodiments, it can be seen that reliability of the light emitting diode package 100 is improved to a significant level when the reinforcing fillers 122 are present in an amount of 50 wt % or more in the light transmissive member 120. Further specifically, it can be seen that reliability of the light emitting diode package 100 is improved to a significant level when the reinforcing fillers 122 are present in an amount of 100 wt % or more in the light transmissive member 120.
That is, the light emitting diode package 100 according to this embodiment has improved reliability when the light transmissive member 120 includes 10 wt % to 200 wt % of the reinforcing fillers 122.
Furthermore, the light emitting diode package 100 has further improved reliability when the light transmissive member 120 includes 50 wt % to 200 wt %, or more specifically, 100 wt % to 200 wt % of the reinforcing fillers 122.
Table 2 shows luminous flux depending upon the content of the reinforcing fillers 122 in the light emitting diode package 100 according to this embodiment upon application of an electric current of 350 mA to the light emitting diode chip 110.
Referring to Table 2, with reference to the luminous flux of the first experimental group not including the fillers, the luminous flux of the third to seventh experimental groups each including the reinforcing fillers 122 was decreased. The third experimental group has a difference in luminous flux of 0.2% with the first experimental group. The fourth experimental group has a difference in luminous flux of 0.7% with the first experimental group and a difference in luminous flux of 0.5% with the third experimental group. The fifth experimental group has a difference in luminous flux of 1.3% with the first experimental group and a difference in luminous flux of 0.6% with the fourth experimental group. The sixth experimental group has a difference in luminous flux of 2% with the first experimental group and a difference in luminous flux of 0.7% with the fifth experimental group. The seventh experimental group has a difference in luminous flux of 3.2% with the first experimental group and a difference in luminous flux of 1.2% with the sixth experimental group. The third to sixth experimental groups having a difference in luminous flux of 2% or less with the first experimental group have a luminous flux reduction rate of 0.7% or less as the content of the reinforcing fillers 122 increases. However, the seventh experimental group has a difference in luminous flux of 1.2% with the sixth experimental group and exhibits rapid increase in luminous flux reduction rate.
From this experiment, it can be seen that the reinforcing fillers 122 are present in an amount of 100 wt % of less in the light transmissive member 120 in order to minimize deterioration in luminous efficacy of the light emitting diode package 100.
That is, the light emitting diode package 100 according to the embodiments has improved reliability when the light transmissive member 120 includes 10 wt % to 200 wt % of the reinforcing fillers 122.
Furthermore, the light emitting diode package 100 according to the embodiments has further improved reliability when the light transmissive member 120 includes 50 wt % to 200 wt % of the reinforcing fillers 122 than when the light transmissive member 120 includes less than 50 wt % of the reinforcing fillers 122.
Furthermore, the light emitting diode package 100 according to the embodiments has significantly improved reliability while minimizing deterioration in luminous efficacy when the light transmissive member 120 includes 50 wt % to 100 wt % of the reinforcing fillers 122.
The light emitting diode package 100 may be manufactured by a method including: preparing a support substrate (not shown); placing light emitting diode chips 110 on the support substrate; forming a light transmissive member 120; polishing an upper surface of the light transmissive member 120; performing a singulation process; and removing the support substrate.
First, multiple light emitting diode chips 110 may be placed on the support substrate. Here, the multiple light emitting diode chips 110 may be placed to be separated from each other.
Then, the light transmissive member 120 may be formed on the support substrate to cover the multiple light emitting diode chips 110.
Next, the upper surface of the light transmissive member 120 may be polished. During polishing of the upper surface of the light transmissive member 120, the reinforcing fillers 122 may be exposed through the upper surface of the light transmissive member 120.
Next, the singulation process is performed by dicing the light transmissive member 120 between the light emitting diode chips 110 to provide individual light emitting diode packages 100. Here, during dicing of the light transmissive member 120, the reinforcing fillers 122 may be exposed through the side surface of the light transmissive member 120.
Next, the support substrate is removed, thereby providing the individual light emitting diode packages 100, as shown in
In the following description of light emitting diode packages according to other embodiments, the same components as those of the light emitting diode package according to the above embodiment will be omitted or briefly described. For details of the omitted or briefly described components, refer to the descriptions of the above embodiment.
The light emitting diode package 200 according to the second embodiment includes a light emitting diode chip 110, a light transmissive member 120, and a barrier member 210.
The light transmissive member 120 covers upper and side surfaces of the light emitting diode chip 110. In addition, the light transmissive member 120 includes a light transmissive resin 121, reinforcing fillers 122, and a wavelength conversion material 123. The reinforcing fillers 122 and the wavelength conversion material 123 are dispersed in the light transmissive resin 121. Here, the wavelength conversion material 123 may be omitted depending upon wavelengths of light emitted from the light emitting diode chip 110.
The barrier member 210 is formed of a material capable of reflecting light and reflects light emitted from the light emitting diode chip 110. For example, the barrier member 210 may include a silicone resin, an epoxy resin, or a mixture thereof. Further, the barrier member 210 may include a reflective material, such as TiO2, SiO2, and Al2O3, in order to improve light transmittance.
According to this embodiment, the barrier member 210 covers a side surface of the light transmissive member 120 and exposes an upper surface of the light transmissive member 120. That is, the barrier member 210 reflects light emitted through the side surface of the light emitting diode chip 110 such that the light can be emitted through the upper surface of the light transmissive member 120. Accordingly, the barrier member 210 may improve luminous efficacy of the light emitting diode package 200 by preventing light loss through the side surface of the light emitting diode package 200.
Further, the barrier member 210 prevents foreign matter from entering the light transmissive member 120 and the light emitting diode chip 110 through the side surface of the light emitting diode package 200, thereby improving reliability of the light emitting diode package 200.
The barrier member 210 may include the reinforcing fillers 122.
The reinforcing fillers 122 have a low coefficient of thermal expansion to suppress expansion or contraction of the barrier member 210 due to temperature variation. Accordingly, the barrier member 210 can secure the light transmissive member 120 such that the light transmissive member 120 does not suffer from variation in length or volume due to temperature variation. Further, the barrier member 210 can prevent the light transmissive member 120 from being peeled off of the light emitting diode chip 110.
In addition, the reinforcing fillers 122 having an elongated rod structure can prevent foreign matter from entering the light emitting diode package 200 through the barrier member 210. Further, even when foreign matter enters the barrier member 210, the reinforcing fillers 122 having an elongated rod structure can prevent the foreign matter from reaching the light transmissive member 120 by blocking or extending an intrusion route of the foreign matter.
Accordingly, the barrier member 210 including the reinforcing fillers 122 can prevent components of the light emitting diode package 200 from being degraded due to effects of the foreign matter.
Although the barrier member 210 is illustrated as including the reinforcing fillers 122, it should be understood that the reinforcing fillers 122 can be omitted so long as it is possible to prevent deterioration in reliability of the light emitting diode package 200 while sufficiently preventing foreign matter from entering the light emitting diode package 200 even without the reinforcing fillers 122.
Each of the light emitting diode packages 300, 400 according to the third and fourth embodiments includes a light emitting diode chip 110, a light transmissive member 120, and a barrier member 210.
The light transmissive member 120 covers an upper surface of the light emitting diode chip 110. In addition, the light transmissive member 120 includes a light transmissive resin 121, reinforcing fillers 122, and a wavelength conversion material 123. The reinforcing fillers 122 and the wavelength conversion material 123 are dispersed in the light transmissive resin 121. Here, the wavelength conversion material 123 may be omitted depending upon wavelengths of light emitted from the light emitting diode chip 110.
Referring to
Referring to
The barrier member 210 is formed of a material capable of reflecting light and reflects light emitted from the light emitting diode chip 110. For example, the barrier member 210 may include a silicone resin, an epoxy resin, or a mixture thereof. Further, the barrier member 210 may include a reflective material, such as TiO2, SiO2, and Al2O3, in order to improve light transmittance.
The barrier member 210 may include the reinforcing fillers 122 dispersed therein. The barrier member 210 including the reinforcing fillers 122 can secure the light transmissive member 120 such that the light transmissive member 120 does not suffer from variation in length or volume due to temperature variation. In addition, the reinforcing fillers 122 of the barrier member 210 can prevent foreign matter from entering the light emitting diode packages 300, 400 through the barrier member 210.
According to the third and fourth embodiments, the barrier member 210 covers the side surface of the light emitting diode chip 110 to reflect light emitted through the side surface of the light emitting diode chip 110. Light emitted through the side surface of the light emitting diode chip 110 is reflected by the barrier member 210 to travel towards the light transmissive member 120 disposed at an upper side of the light emitting diode chip 110.
Therefore, in the light emitting diode packages 300, 400 according to the third and fourth embodiments, the barrier member 210 can prevent light loss through the side surface of each of the light emitting diode packages 300, 400, thereby improving luminous efficacy.
Although certain embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concepts are not limited to such embodiments, but rather to the broader scope of the appended claims and various obvious modifications and equivalent arrangements as would be apparent to a person of ordinary skill in the art.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2019-0001181 | Jan 2019 | KR | national |
This application is a Continuation of U.S. patent application Ser. No. 18/181,970, filed on Mar. 10, 2023, which is a Continuation of U.S. patent application Ser. No. 16/943,144, filed on Jul. 30, 2020, now issued as U.S. Pat. No. 11,605,763, which is a Continuation of International Patent Application No. PCT/KR2019/018786, filed on Dec. 31, 2019, and claims priority from Korean Patent Application No. 10-2019-0001181, filed on Jan. 4, 2019, each of which is incorporated herein by reference for all purposes as if fully set forth herein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 18181970 | Mar 2023 | US |
| Child | 18925005 | US | |
| Parent | 16943144 | Jul 2020 | US |
| Child | 18181970 | US | |
| Parent | PCT/KR2019/018786 | Dec 2019 | WO |
| Child | 16943144 | US |
