TWI772098B - Linear led and application apparatus thereof - Google Patents

Abstract

This invention discloses a linear light-emitting diode and a slim linear LED light-emitting apparatus. The linear light-emitting diode comprising a substrate, plurality of the light-emitting diode chips, bonding wires connecting the anode or cathode of each light-emitting diode chip, and a packaging colloid. The plurality of the light-emitting diode chips are linearly arranged, embedded in the packaging colloid, and the packaging colloid has a horizontal fine trench between two certain adjacent light-emitting diode chips.

Description

Strip light-emitting diode and its application device

The invention relates to a long strip light emitting diode and an application device thereof, in particular to a long strip light emitting diode with lateral thin lateral grooves in the encapsulation colloid, which can improve the cold and heat resistance of the strip light emitting diode Reliability for temperature cycling or thermal shock.

Light Emitting Diode (LED for short) has many characteristics of high brightness, energy saving, multi-color and rapid change, and has been widely used in various lighting fields that require light sources, including the field of automotive lights. In general, most of the LEDs on the market are packaged with a single die, so they are all point-shaped light sources when lit. Early LED headlights also featured multi-point light sources to distinguish them from incandescent bulbs.

Japanese Patents (JPA No. 2012-59736, JPA No. 2016-167518) use a plurality of LED dies to line up and encapsulate them into a long strip of LED strips or LED tubes, which are used in indoor lighting. Some manufacturers use multiple LED dies to line up and encapsulate them into a long strip of LED water pipe lights, which are used in outdoor decorative lights. The above-mentioned long LEDs packaged with multiple LED dies have poor reliability against cold and hot temperature cycles or cold and thermal shocks. However, because the operating environment is mostly indoor room temperature, or outdoor temperature between -30°C and 50°C It is not a harsh environment with a large temperature change range, and there is no problem of failure in short-term application. Relatively speaking, the environment in which LEDs are used in automotive exterior lamps is extremely harsh. Therefore, the automotive industry has very strict requirements on the quality and reliability of LEDs, such as the well-known AEC-Q102 test specifications and USCAR 33 test specifications. Among them, the thermal shock test item of USCAR 33 has a test temperature range from -55℃ to 150℃ ℃, which is far more severe than the use environment of the aforementioned outdoor LED decorative lights.

In order to develop a linear LED vehicle lamp with uniform and granular bright spots, the former patent case TWI708908, patent name: slim line LED light-emitting device, proposes a structure and manufacturing technology of a slim line LED light-emitting device, which uses a plurality of similar LED chips (plurality LED chips) packaged LED Bar (or LED strip) is used as a light source. The LED Bar itself is a continuous and visually uniform line light source, which is different from the general use of a granular LED package as the light source design. Especially suitable for high-quality linear lights. The slender linear LED lighting device is applied to linear lamps with thin light guides, especially car lamps, and can effectively solve many problems of existing LED light sources applied to high-quality vehicle lamps, including visually seeing discontinuous lighting. , uneven light and dark, granular bright spots and other problems that often occurred in previous LED linear lights.

However, for a strip-shaped light-emitting diode (LED) with multiple dies, when the electrodes on the inner LED dies are connected by wire bonding, the connection between the gold wire and the encapsulant is The Coefficient of Linear Thermal Expansion (CLTE) varies greatly. Under the temperature change, the colloid produces thermal stress of extrusion or pulling on the gold wire, which changes back and forth as the temperature drops or rises. Basically, the magnitude of this thermal stress is proportional to the stiffness or bulk modulus of the colloid and the range of temperature changes. In addition, when the length of the light-emitting diode colloid is longer, for those gold wires in the light-emitting diode that are farther from the center of the colloid, the thermal stress exerted by the colloid on the gold wires will be greater. In other words, when the length of a strip-shaped light-emitting diode increases due to the inclusion of more crystal grains, when the temperature changes greatly, the deformation or thermal stress of the inner gold wire also increases accordingly. The magnitude of this thermal stress is closely related to the colloidal material of the light-emitting diode, as detailed below.

Generally, the glue used in the encapsulation of light-emitting diodes is mainly epoxy or silicon. Among them, epoxy resin is a thermosetting resin, which becomes solid after encapsulation, and its point-type coefficient of linear thermal expansion (CLTE) is approximately below the glass transition temperature (Tg). It is 20-40ppm; above the glass transition temperature (Tg), it rises to about 3-4 times, which is greater than the coefficient of linear thermal expansion (CLTE) of the gold wire 14ppm/℃ (at room temperature, but its value does not change much with temperature) . Generally, the Tg temperature requirements of automotive LEDs are relatively high, about 80-120 °C, in order to improve their reliability performance at high temperatures. As for the bulk modulus (Bulk Modulus) of epoxy resin, it also changes with temperature, about 1-3Gpa below the Tg point; it gradually decreases to 0.1-1Gpa from the Tg point to 150°C.

There are two main types of silicones used in LED encapsulation: Methyl Base silicone and Phenyl Base silicone. The Tg temperature of the former is relatively low (below -50℃), so the bulk modulus of methyl silicone gel is relatively low in the environment required by automobiles (-50℃ to 150℃), with Dow-Corning's OE-6351 For example, its bulk modulus is less than 0.01Gpa between -50℃ and 150℃. When the temperature changes, the thermal stress generated by the methyl silicone gel on the gold wires in the light-emitting diode is also lower. Between -50°C and 150°C, the coefficient of linear thermal expansion (CLTE) of Dow-Corning OE-6351 is about 290ppm/°C, which is about 20 times the coefficient of linear thermal expansion (CLTE) of gold wire. As for Phenyl Base silicone, because of its relatively high Refractive Index (1.5-1.6), it is mainly used in the packaging of high-brightness and high-power light-emitting diodes. However, the Tg temperature of Phenyl Base silica gel is relatively high. Taking the Tg of various phenyl silica gels from Dow-Corning as an example, most of them fall between -10°C and 50°C. Therefore, the bulk modulus of these phenyl silicone rubbers varies greatly in the environment required by automobiles (-50°C to 150°C). Taking Dow-Corning's OE-7662 as an example, its bulk modulus is as high as 1GPa at -50°C. It is 100 times that of Dow-Corning methyl silica gel OE-6351, and it drops rapidly around the Tg point, and it is below 3.0MPa when it is above 50°C. When the temperature changes from 0 to -50 °C, the thermal stress generated by the phenyl silicone gel on the gold wire in the light-emitting diode is also relatively high. The coefficient of linear thermal expansion (CLTE) of phenyl silicone also varies significantly with the temperature of the Tg point. Taking Dow-Corning OE-7662 as an example, its coefficient of linear thermal expansion (CLTE) is about 81ppm/ between 0 and -50℃. ℃, which is about one-third of methyl silicone OE-6351, and rises to 181ppm/℃ between 50 and 150 ℃, which is close to methyl silicone OE-6351, and is far greater than 14% of gold wire. ppm/°C.

In the range of elastic deformation, the deformation (strain, Strain) of the material has a linear relationship with the stress (Stress), that is, stress = elastic coefficient (or rigidity coefficient) x strain. For resin materials, the stiffness coefficient is mostly expressed by the bulk modulus (Bulk Modulus, also known as bulk modulus, referred to as bulk modulus), that is, pressure = bulk modulus x volume deformation ratio. In other words, the higher the bulk modulus of the adhesive used in the package, the greater the stress generated under the same amount of deformation. Judging from the characteristics of the commonly used adhesive materials for light-emitting diode packaging above, the bulk modulus of epoxy resin is around 1GPa from -50°C to 150°C, so the thermal stress on the gold wire is the largest, which is also the conventional epoxy resin packaging. The main reason why the LEDs fail to pass the aforementioned automotive specifications. The bulk modulus of phenyl silica gel is also around 1GPa between -50℃ and Tg point. In this low temperature range, the bulk modulus of methyl silica gel is only about 0.01Gpa. The thermal stress generated by silica gel on the gold wire in the light-emitting diode is also much larger than that of methyl silica gel.

Most materials expand and contract with heat, and colloids and gold wires in light-emitting diodes are no exception. When the temperature drops, because the linear thermal expansion coefficient of the colloid is greater than that of the gold wire, the gold wire will be squeezed by the shrinkage of the colloid and deformed. On the contrary, when the temperature rises, because the linear thermal expansion coefficient of the colloid is greater than that of the gold wire, the gold wire will be pulled by the larger expansion amount of the colloid and deform in the opposite direction. In other words, during the temperature change up and down, the gold wire in the light-emitting diode is subjected to thermal stress in different directions and deforms back and forth, resulting in so-called thermal fatigue. When the number of cycles of this temperature change continues to increase, the gold wire inside the LED will break due to the fatigue failure mechanism. The known fatigue life of gold wire (that is, the number of times of fatigue caused by fracture) decreases with the increase of fatigue stress. In other words, the greater the thermal stress of thermal fatigue (Thermal Fatigue), the less times the gold wire can withstand thermal fatigue. When the light-emitting diode is being tested for automobile specifications, under the same temperature cycle or thermal shock test, the greater the thermal stress generated by the colloid, the earlier the gold wire fracture occurs.

In addition, when the temperature changes, the thermal stress on each gold wire in a general elongated light-emitting diode varies from position to position. Because the thermal deformation of the light-emitting diode colloid increases linearly from the center of the colloid to the outer edge of the colloid, the farther the gold wire is from the center of the colloid, the greater the thermal stress and deformation. Therefore, when the length of the light-emitting diode colloid is longer, the thermal stress of the gold wire near the outer edge of the colloid is also greater.

An actual case is used to illustrate that when a light-emitting diode with 4 dies and a length of about 5mm is encapsulated by a wire bonding process, and the encapsulation material is phenyl silicone, including Shin-Etsu's LPS-3435, KER -2460 or Dow-Corning's OE-6631, OE-6636, when the test required by the above automotive specification USCAR 33, due to the excessive thermal stress of the colloid, some gold wires in the light-emitting diode are broken, and most of the light-emitting diodes are finally broken. Average body test failed. Further analysis found that the failure mode of all test failed light-emitting diodes is that the gold wire closest to the edge of the encapsulation colloid breaks, and the gold wire breakage occurs near the first solder joint, that is, close to the upper surface of the LED die. Weld point. Proving the above, the farther the gold wire is from the center of the colloid, the greater the thermal stress and deformation. The present invention aims at the innovation of light-emitting diode colloidal structure design, overcomes the above-mentioned problems, and enables a long strip-shaped light-emitting diode containing multiple crystal grains, even if it is packaged by the wire bonding process, and its packaging Adhesives are high-hardness adhesives, such as phenyl silicone, which can also pass the tests required by automotive specifications, making them suitable for use in automotive exterior lights.

The technical problem to be solved by the present invention is that, for an elongated light-emitting diode containing multiple crystal grains, even if it is packaged by a wire bonding process, and the packaging adhesive is a high-hardness adhesive, such as The long strip-shaped light-emitting diode of phenyl silicone rubber provides an innovative packaging structure and colloidal structure design, which reduces the thermal stress of the gold wire in the light-emitting diode and improves its reliability against cold and hot temperature cycles or cold and heat shocks. Automotive Requirements in USCAR 33 Specifications Thermal shock test. Another feature of the present invention is that the structure can maintain the uniformity of linear light emission at the same time, and will not cause bright spots or dark areas due to the special structure of the colloid. or difficulty in light distribution design.

The strip-shaped light-emitting diode of the present invention can be applied to the former patent case TWI708908, patent name: slender line-type LED light-emitting device, to provide a slender line-type light-emitting diode light-emitting device, which can be used in automobile lamps. The elongated light-emitting diode of the present invention includes a substrate, a plurality of electrical connection wires (eg, gold wires, aluminum wires or copper wires), a plurality of similar light-emitting diode chips, and an encapsulation colloid. A plurality of conductive pads (Electric Conducting Pads) are arranged on the substrate, and a plurality of light-emitting diode grains are arranged linearly with appropriate spacing, and each light-emitting diode grain is fixed on the corresponding on the conductive pad. According to the characteristics of the LED die and electrical connection requirements, a wire bonding process is used to connect one end of a wire to one of the LED die, and the other end to connect to the conductive pad beside the die. Using the encapsulation process, the encapsulation colloid is arranged on the substrate, and the encapsulation colloid covers each light-emitting diode die, each electrical connection wire, and each conductive pad on the substrate. The special feature is the encapsulation. The colloid has a lateral groove with a narrow width between two specific adjacent light-emitting diode crystal grains.

In the long strip light-emitting diode of the present invention, the encapsulation colloid has at least one lateral groove with a narrow width, so that the length of the equivalent colloid covering the electrical connection wires in the light-emitting diode body is shortened, so as to effectively reduce the electrical properties of the colloid. Thermal stress on connecting wires (eg gold wires), thereby reducing the risk of electrical connecting wires breaking due to thermal fatigue.

For a further understanding of the features and technical content of the present invention, please refer to the following detailed descriptions and drawings of the present invention. However, the drawings provided are only for reference and description, and are not intended to limit the present invention.

Z: strip-shaped light-emitting diode light-emitting device

U: long strip light-emitting diode

W: Lateral groove width

H: Height of the bottom of the lateral groove

B: printed circuit board

C: electrical connector

1: Substrate

11, 11a, 11b, 11c, 11d, 11e, 11f: Conductive pads

12: Conductive pad

2: Electrical connection wires

3a, 3b, 3c, 3d, 3e, 3f: LED grains

4: Encapsulating colloid

5: Lateral grooves

51: First lateral groove

52: Second lateral groove

501: Bottom of lateral groove

6: solid crystal glue

FIG. 1 is a three-dimensional schematic diagram of a strip-shaped light-emitting diode according to a first embodiment of the present invention.

FIG. 2 is a schematic side view of a strip-shaped light-emitting diode according to the first embodiment of the present invention.

FIG. 3 is a schematic three-dimensional view of a strip-shaped light-emitting diode according to a second embodiment of the present invention.

FIG. 4 is a schematic side view of an elongated light-emitting diode according to a second embodiment of the present invention.

FIG. 5 is a three-dimensional schematic diagram of a plurality of strip-shaped light-emitting diodes of the present invention applied to a strip-shaped LED light-emitting device.

The following are specific specific examples to illustrate the embodiments of the “strip light-emitting diode and its application device” disclosed in the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. . The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are merely schematic illustrations, and are not drawn according to the actual size, and are stated in advance. The following embodiments will further describe the related technical contents of the present invention in detail, but the disclosed contents are not intended to limit the protection scope of the present invention. Additionally, it should be understood that, although the terms "first," "second," "third," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are primarily used to distinguish one element from another. In addition, the term "or", as used herein, should include any one or a combination of more of the associated listed items, as the case may be.

Referring to FIG. 1 and FIG. 2 , FIG. 1 is a three-dimensional schematic diagram of a long strip light emitting diode (U) according to an embodiment of the present invention, and FIG. 2 is a long strip light emitting diode (U) according to an embodiment of the present invention. Schematic side view. In FIG. 1, the elongated light-emitting diode (U) includes a substrate (1), 12 electrical connection wires (2), 6 light-emitting diode die (3a, 3b, 3c, 3d, 3e, 3f), and an encapsulating colloid (4). Wherein, the encapsulant (4) has a lateral groove (5), that is, the direction of the lateral groove is perpendicular to the arrangement direction of the six light-emitting diode die (3a, 3b, 3c, 3d, 3e, 3f) . The six light-emitting diode dies (3a, 3b, 3c, 3d, 3e, 3f) are all horizontal light-emitting diode dies, and the positive electrode (P) and the negative electrode (N) are both located on the side of the die. On the upper surface, each light-emitting diode die needs two separate electrical connection wires (2) for electrical connection. The substrate (1) includes six conductive pads (11, including 11a, 11b, 11c, 11d, 11e, 11f) and 1 a conductive pad (12) not provided with light-emitting diode die. Wherein, the area of the conductive pad (12) is smaller than that of the conductive pad (11) because there is no need to arrange light emitting diode crystal grains. The 6 light-emitting diode grains (3a, 3b, 3c, 3d, 3e, 3f) are linearly arranged at equal intervals, and the die bonding process is used to make each light-emitting diode grain by the bonding glue ( 6) Fixed on the corresponding conductive pad (11). Using a wire bonding process, one end of each electrical connection wire (2) is connected to one of the light emitting diode chips, and the other end is connected to the adjacent conductive pad (11) or conductive pad (12). The electrical connection wire (2) in this embodiment is a gold wire with a wire diameter of 1.2 mil. Using an encapsulation process, the encapsulation compound (4) is disposed on the substrate 1 and covers each light-emitting diode die, each electrical connection wire (2), and each of the substrates (1). A conductive pad (11, 12). One of the features of the present invention is that the encapsulating colloid (4) has a lateral groove (5) between two specific adjacent light-emitting diode crystal grains. In this embodiment, the lateral grooves (5) in the encapsulating colloid (4) are arranged between the third light-emitting diode die (3c) and the fourth light-emitting diode die (3d). The direction of the lateral groove (5) is perpendicular to the arrangement direction of the six light-emitting diode crystal grains.

In this embodiment, the lateral grooves (5) are formed on a preform of the sealing compound (not shown in the figure) of the light-emitting diode, and the pre-shape of the sealing compound is cut by a diamond cutting sheet. Therefore, in FIG. 2, the width (W) of the transverse groove (5) is determined by the thickness of the selected diamond cutting sheet. Basically, the width (W) of the lateral groove (5) should not be too large, so as not to affect the light shape of the light emitting diode, or cause visual unevenness. Therefore, limited by the thickness limit of the diamond cut sheet, the preferred width (W) of the transverse groove (5) of the present invention is 0.1-0.3mm. In FIG. 2, the depth of the lateral groove (5) is determined by the vertical distance between the bottom of the lateral groove (501) and the surface of the upper conductive pad layer of the substrate (1) or the height (H) of the bottom of the lateral groove, so as to be as close as possible to the light-emitting two The upper surface of the polar body grains (3c, 3d) is the control principle. The preferred embodiment of the present invention is to control the height (H) of the bottom of the lateral trench to be between 100 micrometers (μm) and 500 micrometers (μm), so that the colloid can still completely cover each light-emitting diode die and Each conductive pad on the substrate can effectively reduce the thermal stress of the colloid on the electrical connection wires.

As for how to select two specific adjacent light-emitting diode dies to set lateral grooves (5), or to set several lateral grooves (5), it depends on the total length of the encapsulation colloid, the encapsulation colloid material, and the electrical connection. The tensile strength of the wire (2) is related to the temperature range of the thermal cycle (or thermal shock). In general, the greater the number of lateral grooves on the light-emitting diode colloid, the smaller the thermal stress on the electrical connection wires in the light-emitting diode, and the higher the reliability against thermal cycling or thermal shock. On the contrary, when the number of lateral grooves on the light-emitting diode colloid increases, the difficulty or cost of manufacturing is also relatively increased.

The effect of the present invention is described as follows: In the strip-shaped light-emitting diode in this embodiment, there is a transverse groove in the middle of the encapsulating colloid whose depth is close to the surface of the light-emitting diode. Half of the encapsulating colloid, i.e. forming two separate new colloid centers. For the gold wire located at the rightmost edge of the light-emitting diode, it is equivalent to halving the distance from the center of the right cladding colloid. When the effective length of the coating colloid to generate thermal stress on the gold wire is shortened, the thermal stress of the colloid on the gold wire is relatively reduced, thus reducing the risk of the gold wire breaking due to thermal fatigue, and improving the light-emitting diode to withstand cold and heat cycles or cold and heat. Stamping life and reliability. Based on the above, the present invention is not limited to the material and type of the substrate (1). For example, the substrate (1) is a two-layer (2-layer) substrate (Substrate) with conductive layers on the upper and lower layers (front and back), which can be a BT (Bismaleimide Triazine) board, a ceramic substrate, or a separate metal block A composite substrate embedded in resin. Alternatively, the substrate (1) may also be a BT board or a ceramic substrate with two or more conductive layers, In order to increase the flexibility of circuit routing design. In addition, the present invention is not limited by the shape of the conductive pads (11) and (12).

The present invention can be applied to light-emitting diode die of different implementations, including vertical light-emitting diode die (referring to the positive electrode (P) or negative electrode (N) of the LED die being separated on different sides of the LED die , that is, one is on the front and the other is on the bottom), horizontal light-emitting diode die (meaning that the positive (P) and negative (N) of the LED die are on the front or upper surface of the LED die), etc. Among them, both the vertical LED die and the horizontal LED die need to be packaged through die bonding and wire bonding processes, so there is the aforementioned problem that the gold wire is broken due to thermal fatigue.

FIG. 3 and FIG. 4 show the second embodiment of the present invention, and the LED die shown in the figures is a vertical LED die. One of the electrodes (eg, the positive electrode (P)) of the vertical light-emitting diode die is located on the upper surface of the die, and the other electrode (eg, the negative electrode (N)) is located on the lower surface of the die. In this embodiment, the light-emitting diode chips (3a, 3b, 3c, 3d, 3e, 3f) are first fixed on the corresponding conductive pads (11) with a conductive die-bonding glue (6) (such as silver glue). , including 11a, 11b, 11c, 11d, 11e, 11f), and then respectively connect the electrodes (P) on the upper surface of each light-emitting diode die by electrically connecting wires (2) through a wire bonding process. and another conductive pad (11) or conductive pad (12) next to it. In this embodiment, the light-emitting diode die (3a) is fixed on the corresponding conductive pad (11a), and the electrical connection wire (2) connecting the electrode (P) on the surface of the light-emitting diode die (3a) is connected to In the conductive pad (11b), and so on, only the electrical connection wire (2) connecting the electrode (P) on the surface of the light-emitting diode die (3f) is hit on the conductive pad (12).

In this embodiment, the encapsulant (4) includes two lateral grooves (51, 52), wherein the first lateral groove (51) is disposed on the second light-emitting diode die (3b) and the third Between the LED die (3c), the second lateral trench (52) is disposed between the fourth LED die (3d) and the fifth LED die (3e). During this time, the direction of the lateral trenches (51, 52) is perpendicular to the arrangement direction of the six light-emitting diode crystal grains (3a, 3b, 3c, 3d, 3e, 3f). As mentioned earlier, The number of lateral grooves on the light-emitting diode colloid of this embodiment increases, so the reliability of the anti-cold-heat temperature cycle or thermal shock also increases accordingly.

In the long strip light-emitting diode of the present invention, the encapsulation colloid has at least one lateral groove with a narrow width, so that the effective length of the colloid to generate thermal stress on the electrical connection wire is shortened, and the inclusion of a bit can effectively reduce the thermal effect of the colloid on the wire. stress, thereby reducing the risk of wire breakage due to thermal fatigue.

It should be further explained that the present invention does not limit the wire bonding direction of the electrical connection wires of the light-emitting diodes, but the wire bonding direction of the electrical connection wires on both sides of each colloidal lateral groove should be parallel to the lateral grooves as much as possible. direction, so as to avoid affecting the formation of the lateral groove of the colloid, or the colloid cannot cover each electrical connection wire.

In addition, it should be noted that the present invention is not limited by the number of light-emitting diode crystal grains. The present invention is also not limited by the number of lateral grooves on the light emitting diode colloid. The formation of the lateral grooves on the light-emitting diode colloid of the present invention is not limited to using a diamond cutting sheet to cut the encapsulant preform, but also can use a molding process, such as direct molding, transfer Molding (Transfer Molding) or injection molding (Injection Molding) and other processes, carry out colloid coating, and at the same time form lateral grooves on the colloid. However, when the colloidal lateral groove is formed by the molding process, the demolding conditions are limited. The colloidal lateral groove must have a draft angle and a relatively wide width of the lateral groove, that is, the light-emitting diode crystal. The spacing between particles is relatively large, and the number of transverse grooves that can be provided in the colloid is relatively small.

In the functional test of an actual sample of the present invention, the resin selected for the light-emitting diode encapsulant is a phenyl silica gel from Dow Corning. Two different light-emitting diodes with the same length and the same light-emitting diode crystal grains arranged inside, one is a colloidal light-emitting diode with lateral grooves and the other is a colloidal light-emitting diode without lateral grooves, to make a car. The thermal shock test in USCAR 33 of the standard LED, the test conditions are cold and thermal shock between low temperature -55 ℃ and high temperature 150 ℃, and the test time is 1512 hours (equivalent to 3000 cycles). The test results show that after the test time is 1344 hours, the colloid has no transverse The failure rate of the light emitting diode samples to the trench was 80/80, ie all 80 test samples failed. For the light-emitting diode samples with lateral grooves in the colloid, after the test time is 1512 hours, the failure rate of the test samples is 0/80, that is, there is no failure. The test results fully confirm the specific efficacy and progress of the present invention.

FIG. 5 is a schematic three-dimensional view of applying the strip-shaped light-emitting diode of the present invention to a strip-shaped LED light-emitting device (Z). In this embodiment, the strip-shaped light-emitting diode light-emitting device (Z) includes a printed circuit board (B), a plurality of strip-shaped LEDs (U) of the present invention, and at least one electrical connector (C). The strip-shaped light-emitting diode (U) and the electrical connector (C) are arranged on the printed circuit board (B) by the SMT process to form the strip-shaped LED light-emitting device (Z). The present invention is not limited by the number of strip-shaped light-emitting diodes (U).

The contents disclosed above are only preferred feasible embodiments of the present invention, and are not intended to limit the scope of the present invention. Therefore, any equivalent technical changes made by using the contents of the description and drawings of the present invention are included in the application of the present invention. within the scope of the patent.

U: long strip light-emitting diode

1: Substrate

11: Conductive pad

2: Electrical connection wires

3a, 3b, 3c, 3d, 3e, 3f: LED grains

4: Encapsulating colloid

5: Lateral grooves

501: Bottom of lateral groove

6: solid crystal glue

W: Lateral groove width

H: Height of the bottom of the lateral groove

Claims (6)

An elongated light-emitting diode, comprising: a substrate, including a plurality of conductive pads; a plurality of light-emitting diode crystal grains, the plurality of light-emitting diode crystal grains are linearly arranged, and each of the light-emitting diodes The diode die is arranged on the corresponding conductive pad; a plurality of electrical connection wires, one end of each of the electrical connection wires is connected to one of the light-emitting diode die, and the other end is connected to the adjacent the conductive pad; and an encapsulant disposed on the substrate, the encapsulant coats each of the light-emitting diode die, each of the electrical connection wires and each of the one of the conductive pads, the encapsulant has a lateral groove between two adjacent light-emitting diode dies, and the direction of the lateral groove is substantially perpendicular to the plurality of light-emitting diodes The arrangement direction of the die, and the bottom of the lateral groove is between the upper surface and the bottom surface of the light-emitting diode die on both sides of the lateral groove, and the light-emitting diode die on both sides of the lateral groove. The direction of the electrical connection wires is substantially parallel to the direction of the lateral grooves. The strip-shaped light-emitting diode according to claim 1, wherein the lateral groove is formed by cutting the packaging compound after the light-emitting diode die is subjected to an encapsulation process, and The width of the lateral groove is between 0.1 mm and 0.3 mm. The strip-shaped light-emitting diode according to claim 1, wherein the vertical distance between the bottom of the lateral groove and the upper surfaces of the conductive pads on both sides thereof is between 0.1 mm and 0.5 mm. The strip-shaped light-emitting diode according to claim 1, wherein the lateral grooves are formed by molding during the encapsulation process of the light-emitting diode die form. An elongated light-emitting diode, comprising: a substrate including a plurality of conductive pads; six vertical light-emitting diode crystal grains, the six light-emitting diode crystal grains are linearly arranged at equal intervals, and each One of the light-emitting diode die is disposed on the corresponding conductive pad; six electrical connection wires, one end of each of the electrical connection wires is connected to one of the light-emitting diode die, and the other end is connected to one of the light-emitting diode die. connected to the adjacent conductive pads; and an encapsulant disposed on the substrate, the encapsulant wraps each of the light-emitting diode chips, each of the electrical connection wires and the each of the conductive pads on the substrate; wherein, the encapsulant has a first lateral groove between the second LED die and the third LED die, The direction of the first lateral groove is perpendicular to the arrangement direction of the six light-emitting diode crystal grains, and the encapsulation colloid is located between the fourth light-emitting diode crystal grain and the fifth light-emitting diode crystal grain. There is a second lateral groove between the die, the direction of the second lateral groove is perpendicular to the arrangement direction of the six light-emitting diode die, the first lateral groove and the second lateral groove The bottom of the groove is between the upper surface and the bottom surface of the light-emitting diode die on both sides of the groove, and the light-emitting diode die on both sides of the first lateral groove and the second lateral groove The directions of the electrical connection wires are respectively parallel to the directions of the first lateral groove or the second lateral groove beside it. A strip-shaped light-emitting diode light-emitting device, comprising: a printed circuit board, which includes at least one electrical connector and a plurality of strip-shaped light-emitting diodes, each of the strip-shaped light-emitting diodes includes : a substrate, including a plurality of conductive pads; a plurality of light-emitting diode crystal grains, the plurality of light-emitting diode crystal grains are linearly arranged, and each of the light-emitting diode crystal grains is disposed on the corresponding conductive pad; a plurality of electrical connection wires, One end of each of the electrical connection wires is connected to one of the light-emitting diode die, and the other end is connected to the adjacent conductive pad; Glue covers each of the light-emitting diode die, each of the electrical connection wires and each of the conductive pads on the substrate, and the encapsulant is in two adjacent ones of the light-emitting diodes. There is a lateral groove between the polar body crystal grains, the direction of the lateral groove is substantially perpendicular to the arrangement direction of the plurality of light-emitting diode crystal grains, and the bottom of the lateral groove is between the two sides of the lateral groove. Between the upper surface and the bottom surface of the diode die, the direction of the electrical connection wires of the light emitting diode die on both sides of the lateral groove is substantially parallel to the direction of the lateral groove.

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