JP5407993B2 - Vehicle headlamp - Google Patents

Description

  The present invention relates to an LED light-emitting device in which an LED chip is mounted on a substrate, and a vehicle headlamp using the LED light-emitting device.

  In order to flow a large current for high light output and / or to drive in a low current region with high luminous efficiency by reducing the current density per area, the LED chip becomes larger (one side is 500 μm to 1 mm). In this LED chip, a plurality of wire bonding pad electrodes are formed in order to supply current uniformly to a light emitting surface of a large area (Patent Documents 1 and 2).

  Conventional example 1 shown in FIG. 10 is an LED light emitting device 110 in which four large LED chips 101 are arranged in a row and in series in a single circuit on a submount substrate 111 having a minimum size necessary for mounting. . On the light emitting surface of the LED chip 101, two pad electrodes 102 at both corners of one side and finger electrodes (not shown) extending linearly from both pad electrodes 102 and dispersed on the light emitting surface are formed. . The submount substrate 111 is a wiring substrate including a ceramic plate 112 and five conductive patterns 113 formed on the upper surface thereof. The LED chips 101 are placed one by one on the lower four patterns, and the lower surfaces of the chips are joined electrically and thermally. Further, two wires 109 and 109 are erected and bonded from the two pad electrodes 102 and 102 of each LED chip 101 to the bonding region of the upper adjacent conductive pattern 113 in FIG. The installation direction of the wires 109 and 109 from the pad electrodes 102 and 102 in a plan view is a direction perpendicular to the sides 101a and 101b facing the LED chip 101 (a direction away from the right angle; the same applies hereinafter). Therefore, there is a problem that the pattern width of the conductive pattern 113 for bonding the ends of the two wires 109 and 109 is increased, and the size of the submount substrate 111 is increased.

  Conventional example 2 shown in FIG. 11 is an LED light emitting device 120 in which conventional example 1 is arranged in two rows, that is, eight LED chips 101 are arranged in two rows on a submount substrate 121 and mounted in series in two circuits. . The installation direction of the wires 109 is the same as that in the first embodiment. Since one wire 109 in one row and one wire 109 in the other row are arranged between the two rows of LED chips 101, there is a problem that the chip interval is increased and the size of the submount substrate 121 is also increased. It was.

  Conventional example 3 shown in FIG. 12 is an LED light-emitting device in which eight LED chips 101 are mounted in a two-row arrangement / series two-circuit on a base substrate 131 that also has a power receiving terminal for contacting a power supply terminal of a lighting fixture. 130. The installation direction of the wires 109 is the same as that in the first embodiment. For example, two anode patterns 113a and one cathode common pattern 113c of the conductive pattern 113 are extended to a lower side which is an attachment side of the LED light emitting device 130, and each extended end portion is used as a power receiving terminal. Two anode patterns 133a are located on the left side and center of the attachment side, and a cathode common pattern 133c is located on the right side of the attachment side. When the two-circuit LED chip 101 is driven simultaneously, more current flows in the cathode common pattern 133c than in each anode pattern 133a, so that the voltage drop due to the internal resistance of the pattern is large. Therefore, the cathode common pattern 133c should be wider than each anode pattern 133a to reduce the internal resistance. However, since the power supply terminals 136 included in the attachment holder of the lighting fixture are arranged at regular intervals and their positions are fixed and cannot be changed in many cases, the cathode common pattern 133c may not be sufficiently wide. That is, even if the right cathode common pattern 133c is to be widened, there is a limit because it cannot be applied to the central power supply terminal 136.

  Conventional example 4 shown in FIG. 13 is a vehicle headlamp 140 configured by using LED light emitting device 110 of conventional example 1. In this vehicle headlamp 140, the LED light emitting device 110 of Conventional Example 1 is mounted upward on a base substrate 141 with a power receiving terminal so that light can be emitted upward or around from the light emitting surface of the LED chip 101. A reflector 142 extending to the periphery of the LED chip 101 is provided behind the light emitting device 110 (left side in FIG. 13) so as to reflect the upward or ambient light forward, and forward of the LED light emitting device 110 (FIG. 13). In the right side), a head lens (not shown) is provided to collect the forward light in a predetermined range.

  In addition, the LED light emitting device 110 is arranged so that the direction perpendicular to the first side 101 a of the LED chip 101 is the rearward direction from the LED chip 101 toward the reflector 142. As described above, the erection direction of the wire 109 from the pad electrode 102 on the first side 101a side is also a direction perpendicular to the first side 101a of the LED chip 101. Therefore, the wire 109 enters in parallel on the rear optical path from the LED chip 101 toward the reflector 142, and a shadow of the wire is generated. There is a problem that the amount of light is reduced by the shadow of the wire, or the appearance of the shadow is deteriorated when the shadow is visible from the outside.

  Patent Document 1 describes a vehicle headlamp that reflects light emitted upward or around from a light emitting surface of an LED chip forward by a reflector, but the bonding wire of the LED chip is in the irradiation direction. There is no disclosure of a configuration that passes in the forward direction and that has a plurality of pad electrodes on the light emitting surface, particularly a configuration that has pad electrodes at two diagonal corners. Patent Document 3 describes a mode in which pad electrodes are provided at two diagonal corners of a light emitting surface of an LED chip. As a result of mounting the LED chip obliquely on a substrate, the bonding wire is inclined and installed. However, the subject of the present invention is to perform the wire bonding process smoothly, and the subject and configuration are different from the present invention.

JP 2005-32661 A JP 2006-245542 A JP 2000-124508 A

  A first object of the present invention is to reduce the size of the substrate by reducing the width of the bonding region of the conductive pattern of the substrate to which the wire is bonded in the LED light emitting device in which the LED chip is mounted on the substrate. When LED chips are arranged in a plurality of rows, the chip interval between rows is to be reduced.

  A second object of the present invention is to reduce the electrical resistance and the voltage drop in an LED light emitting device in which an LED chip is mounted on a substrate so that the common pattern in the conductive pattern of the substrate can be widened. It is in.

  A third object of the present invention is a vehicle headlamp that uses an LED light emitting device in which an LED chip is mounted on a substrate and reflects light emitted upward or around from the light emitting surface of the LED chip forward by a reflector. The object is to prevent the wire from entering the optical path from the LED chip to the reflector so as not to cause a shadow of the wire, and to prevent a decrease in the amount of light and a deterioration in appearance.

  In order to solve the above problems, the following means (1) to (6) were taken.

(1) An LED chip in which the first side and the second side facing each other are parallel to each other on the substrate in which the first side and the second side facing each other are parallel to each other. Is mounted so that the second side and the second side are parallel to each other with an interval between them,
Between the pad electrode on the first side of the two pad electrodes provided at the two diagonal corners of the upper surface of the LED chip and the bonding area of the conductive pattern provided on the upper surface on the first side of the substrate In addition, the wire is installed so that the installation direction from the pad electrode in a plan view is a direction inclined by 15 to 40 degrees away from the first side with respect to the perpendicular separation direction with respect to the first side,
Between the pad electrode on the second side of the two pad electrodes and the bonding area of the conductive pattern provided on the upper surface on the second side of the substrate, a wire is installed from the pad electrode in plan view. An LED light-emitting device constructed such that the direction is a direction inclined by 15 to 40 degrees in a direction approaching the second side with respect to a direction perpendicular to the second side.

(2) In the LED light-emitting device of (1) above, a plurality of LED chips are mounted on a substrate so that the first sides thereof are aligned in a straight line, and the plurality of LED chips constitute a series circuit. LED light-emitting device made to do.

(3) a first LED chip in which the first side and the second side facing each other are parallel to each other, and a first LED chip in which the first and second sides facing each other are parallel to each other; The first side of the first LED chip and the first side of the substrate are parallel to each other on the substrate having the second side parallel to the second side of the first LED chip. The first side of the second LED chip is parallel to each other with a chip interval, and the second side of the second LED chip and the second side of the substrate are parallel to each other with an interval between them,
Of the two pad electrodes provided at the two diagonal corners of the upper surface of the first LED chip, the pad electrode on the first side and the bonding region of the conductive pattern provided on the upper surface of the first side of the substrate; The wire is installed so that the installation direction from the pad electrode in a plan view is a direction inclined 15 to 40 degrees away from the first side with respect to the direction perpendicular to the first side. ,
Of the two pad electrodes provided at two diagonal corners on the upper surface of the first LED chip, the pad electrode on the second side and the conductive surface provided on the upper surface of the substrate near the first LED chip in the chip interval. Between the bonding region of the pattern, the wire is inclined in a direction inclined by 15 to 40 degrees so that the erection direction from the pad electrode in a plan view approaches the second side with respect to the direction perpendicular to the second side. Erected as it is,
Of the two pad electrodes provided at the two diagonal corners of the upper surface of the second LED chip, the pad electrode on the first side and the conductivity provided on the upper surface of the substrate near the second LED chip in the chip interval. Between the bonding area of the pattern, the wire is inclined in a direction inclined by 15 to 40 degrees so that the erection direction from the pad electrode in plan view is away from the first side with respect to the direction perpendicular to the first side. Erected as it is,
Of the two pad electrodes provided at the two diagonal corners of the upper surface of the second LED chip, the pad electrode on the second side and the bonding region of the conductive pattern provided on the upper surface on the second side of the substrate, The wire is installed so that the installation direction from the pad electrode in a plan view is inclined by 15 to 40 degrees in a direction approaching the second side with respect to the direction perpendicular to the second side. ,
The LED light-emitting device which comprised the parallel circuit with the 1st LED chip and the 2nd LED chip.

(4) In the LED light-emitting device according to (3) above, a plurality of first LED chips are mounted on a substrate so that the first sides thereof are aligned in a straight line, and the plurality of first LED chips are A series circuit is configured, and a plurality of second LED chips are mounted on a substrate so that the first sides thereof are aligned in a straight line, and the plurality of second LED chips configure a series circuit. LED light emitting device.

(5) In the LED light-emitting device according to (3) or (4) above, the third side of the substrate is an attachment side to the lighting fixture, and a common pattern of one pole of the parallel circuit is arranged at the center of the attachment side And the LED light-emitting device which has arrange | positioned two patterns of the other pole of the said parallel circuit in the both sides which pinch | interpose the center part of this attachment side.

(6) An LED chip in which the first side and the second side facing each other are parallel to each other on the substrate in which the first side and the second side facing each other are parallel to each other. Are mounted in parallel so that the second side and the second side are parallel to each other, and the plurality of LED chips are arranged in a line in which the first sides are aligned in a straight line. So that the plurality of LED chips constitute a series circuit,
Between the pad electrode on the first side of the two pad electrodes provided at the two diagonal corners of the upper surface of the LED chip and the bonding area of the conductive pattern provided on the upper surface on the first side of the substrate In addition, the wire is installed so that the installation direction from the pad electrode in plan view is a direction inclined 15 to 40 degrees away from the first side with respect to the perpendicular separation direction with respect to the first side, and The wire does not extend in a direction perpendicular to the first side of the adjacent LED chip that is oriented away from the first side,
Between the pad electrode on the second side of the two pad electrodes and the bonding area of the conductive pattern provided on the upper surface on the second side of the substrate, a wire is installed from the pad electrode in plan view. Using an LED light emitting device constructed so that the direction is a direction inclined by 15 to 40 degrees in a direction approaching the second side with respect to the direction perpendicular to the second side,
The LED light emitting device is arranged upward so that light can be emitted upward or around from the upper surface of the LED chip,
A reflector extending around the LED chip is provided behind the LED light-emitting device so as to reflect the upward or ambient light forward,
By arranging the LED light-emitting device so that the direction perpendicular to the first side of the LED chip is the rearward direction from the LED chip to the reflector, the wire laid from the pad electrode on the first side becomes the LED chip. Vehicle headlamps that do not enter the rear light path from the camera to the reflector.

  Below, the reason of each element in each said means, an illustration, a preferable aspect, etc. are demonstrated.

1. LED chip The LED chip only needs to be provided with two pad electrodes at at least two diagonal corners of the upper surface, an aspect in which both are n electrodes, an aspect in which both are p electrodes, Any of the two embodiments may be a combination of an n electrode and a p electrode. When the two are the same pole, the other pole can be provided on the lower surface of the LED chip, and in this case, a conductive support substrate is provided.
A chip including a conductive support substrate is preferable, and a manufacturing method thereof is preferably an LLO (laser lift-off) method. Since the chip based on the LLO method has a light emitting surface only on the top surface of a very thin semiconductor layer and less light is emitted from the side surface to the side, the orientation (FWHM) is narrower and the luminous intensity is higher than other chips. This is because it is easy to irradiate the reflector with light and to easily perform optical control. On the other hand, although a chip including a transparent substrate such as sapphire or GaN is applicable, light is emitted from the side surface of the substrate by light guide in the substrate, so that the orientation becomes wide.
Although the size is not particularly limited, in order to cope with a large current and / or to reduce the current density and drive in a small current region with high light emission efficiency, a large-sized rectangle having a side of 500 μm to 1.5 mm. Those are preferred.
The emission color is not particularly limited, and examples thereof include those having a peak wavelength in a red region, a green region, a blue region, a purple region, or an ultraviolet region. In the case where a phosphor provided in the vicinity of the LED chip is excited to obtain white together with fluorescence, those having a peak wavelength in a blue region, a violet region, or an ultraviolet region are preferable (particularly, the vehicle headlamp of (6) above). If).
The material of the semiconductor layer is not particularly limited, and examples thereof include gallium nitride (GaN), zinc oxide (ZnO), zinc selenide (ZnSe), and silicon carbide (SiC).
The type of the light emitting layer is not particularly limited, but a multiple quantum well type is preferable in order to increase the light emission efficiency.

2. Substrate The substrate is not particularly limited, and may be, for example, a submount substrate having a minimum size necessary for mounting an LED chip, or may be a base substrate provided with a power receiving terminal for contacting a power supply terminal of a lighting fixture. . Although it does not specifically limit as a material of a board | substrate, Ceramics, such as aluminum nitride, an alumina, a boron nitride, can be illustrated.

3. The wire erection direction from the pad electrode on the first side of the wire LED chip is a direction inclined 15 to 40 degrees away from the first side with respect to the direction perpendicular to the first side, and the LED chip The reason for setting the wire erection direction from the pad electrodes on the two sides to the direction inclined 15 to 40 degrees toward the second side with respect to the direction perpendicular to the second side is as follows.
The LED light emitting device of (1) and (2) can be used by reflecting light upward from the upper surface of the LED chip or surrounding light forward by a reflector, like the vehicle headlamp of (6) above. Many.
In this case, when the first side is on the reflector side, the portion of the wire from the pad electrode on the first side side, in particular, the portion immediately rising from the pad electrode is rearward and obliquely upward from the LED chip toward the reflector. It is easy to be located on the optical path of the emitted light. Therefore, the erection direction of the wire is inclined in a direction away from the first side with respect to the perpendicular separation direction D so that the portion of the wire is not positioned on the optical path. The reason why the inclination angle is set to 15 to 40 degrees is that when the inclination angle is less than 15 degrees, the effect of reducing the width of the bonding region of the conductive pattern in the above (1) to (4) becomes low, and exceeds 40 degrees. When a plurality of LED chips are mounted in a row as in (2) and (4) to form a series circuit, the wires are positioned on the optical path emitted from the adjacent LED chips toward the reflector. This is because there is a risk of doing so. The tilt angle is more preferably 20 to 40 degrees.
On the other hand, the light radiated forward from the LED chip is centered on the light radiated straight forward, and the light radiated obliquely upward is not used much. Of the wire from the pad electrode on the second side, the portion immediately rising from the pad electrode is difficult to be positioned on the optical path of the light emitted straight forward. Therefore, the erection direction of the wire 9b is inclined in the direction approaching the second side with respect to the perpendicular separation direction, and the wire from the pad electrode on the first side and the wire from the pad electrode on the second side are arranged. This prevents the tips on the conductive pattern side from being too far apart, making it easier to provide the conductive pattern. The reason why the inclination angle is set to 15 to 40 degrees is that when the inclination angle is less than 15 degrees, the effect of reducing the width of the bonding region of the conductive pattern in the above (1) to (4) becomes low, and exceeds 40 degrees. This is because a portion of the wire from the pad electrode on the second side is away from the pad electrode and is positioned on the optical path of the light emitted straight forward. The tilt angle is more preferably 20 to 40 degrees.

4). Lighting fixture The lighting fixture using the LED light-emitting device of the present invention is not particularly limited, and examples thereof include a vehicle headlamp, a building lighting lamp, and a projector lamp.

According to the present invention, in an LED light emitting device in which an LED chip is mounted on a substrate, the width of the bonding region of the conductive pattern of the substrate to which the wire is bonded is reduced, the size of the substrate is reduced, and the LED chip is further mounted. When arranged in a plurality of rows, the chip interval between rows can be reduced. In addition to this effect, in a vehicle headlamp that reflects light emitted upward or around from the light emitting surface of the LED chip with a reflector, the wire is prevented from entering the optical path from the LED chip to the reflector. It is possible to prevent shadows from occurring, and to prevent a decrease in light amount and deterioration in appearance.

1 is a plan view of an LED light emitting device of Example 1. FIG. (A) is a perspective view of the LED chip used for the LED light-emitting device, and (b) is a IIb-IIb sectional view of FIG. 6 is a plan view of an LED light-emitting device of Example 2. FIG. 6 is a plan view of an LED light-emitting device of Example 3. FIG. 6 is a plan view of an LED light-emitting device of Example 4. FIG. It is a principal part top view of the vehicle headlamp of Example 5 (using the LED light-emitting device of Example 1). It is a sectional side view of the headlamp for vehicles. It is a principal part top view of the headlamp for vehicles of Example 6 (using the LED light-emitting device of Example 3). It is a sectional side view of the headlamp for vehicles. It is a top view of the LED light-emitting device of the prior art example 1. It is a top view of the LED light-emitting device of the prior art example 2. It is a top view of the LED light-emitting device of the prior art example 3. It is a principal part top view of the vehicle headlamp of the prior art example 4 (using the LED light-emitting device of the prior art example 1).

The LED chip in which the first side and the second side facing each other are parallel to each other on the substrate in which the first side and the second side facing each other are parallel to each other, the first side and the first side are spaced apart from each other. Mounted in parallel so that the second side and the second side are parallel to each other with a space between them, and a plurality of the LED chips are mounted so that the first sides are aligned in a straight line And a plurality of the LED chips constitute a series circuit,
Between the pad electrode on the first side of the two pad electrodes provided at the two diagonal corners of the upper surface of the LED chip and the bonding area of the conductive pattern provided on the upper surface on the first side of the substrate In addition, the wire is installed so that the installation direction from the pad electrode in plan view is a direction inclined 15 to 40 degrees away from the first side with respect to the perpendicular separation direction with respect to the first side, and The wire does not extend in a direction perpendicular to the first side of the adjacent LED chip that is oriented away from the first side,
Between the pad electrode on the second side of the two pad electrodes and the bonding area of the conductive pattern provided on the upper surface on the second side of the substrate, a wire is installed from the pad electrode in plan view. Using an LED light emitting device constructed so that the direction is a direction inclined by 15 to 40 degrees in a direction approaching the second side with respect to the direction perpendicular to the second side ,
The LED light emitting device is arranged upward so that light can be emitted upward or around from the upper surface of the LED chip,
A reflector extending around the LED chip is provided behind the LED light-emitting device so as to reflect the upward or ambient light forward,
By arranging the LED light-emitting device so that the direction perpendicular to the first side of the LED chip is the rearward direction from the LED chip to the reflector, the wire laid from the pad electrode on the first side becomes the LED chip. This is a vehicle headlamp that is prevented from entering the rearward optical path toward the reflector.
As a result, the width of the bonding area of the conductive pattern of the substrate to which the wire is bonded can be reduced to obtain an LED light-emitting device with a reduced size of the substrate. It can also prevent the appearance from deteriorating .
Mounting a plurality of LED chips in rows and columns kite in a plurality of rows, it is also possible to form a parallel circuit.

  The embodiment 1 shown in FIGS. 1 and 2 is an LED light emitting device 10 in which four LED chips 1 are arranged in a row and in a series in a single circuit on a submount substrate 11 having a minimum size necessary for mounting. is there.

  The LED chip 1 used in Example 1 has a square shape with a side of 1 mm in plan view, and the first side 1 a and the second side 1 b facing each other in FIG. 1 are parallel to each other. The LED chip 1 is formed by an LLO (laser lift-off) method. As shown in FIG. 2, the n-electrode 2, the semiconductor layer 3, the conductive adhesive layer 4, and the conductive layer are sequentially arranged from the top. A conductive substrate 5 and a p-electrode 6. The semiconductor layer 3 includes an n-type cladding layer, a multiple quantum well light-emitting layer, and a p-type cladding layer (not shown) in order from the top. The semiconductor layer 3 is formed in a wide area extending substantially over the entire square, and the n electrode 2 is a pair of upper surfaces that are light emitting surfaces so as to supply current uniformly to the upper surface of the n-type cladding layer that is the light emitting surface. Two pad electrodes 7a and 7b for wire bonding provided at two corners, and finger electrodes (not shown) extending linearly from both pad electrodes 7a and 7b and dispersed on the upper surface are provided. The p electrode 6 is provided on the entire lower surface of the conductive substrate 5. The LED chip 1 is not limited to the above example as long as it has two pad electrodes at at least two diagonal corners of the upper surface. For example, a p-electrode may be provided on the upper surface and an n-electrode may be provided on the opposite surface, or a p-electrode and an n-electrode may be provided on the light emitting surface.

  The submount substrate 11 is a wiring substrate including an insulating and high thermal conductivity ceramic plate 12 (for example, aluminum nitride) and a conductive pattern 13 formed on the upper surface thereof. The first side 11a and the second side 11b facing each other are parallel to each other. The conductive patterns 13 are five patterns arranged in a row with an insulating region 14 in between. The LED chips 1 are placed one by one in the lower four patterns in FIG. Electrically and thermally bonded. Further, two wires 9a and 9b are installed and bonded from the two pad electrodes 7a and 7b of the n-electrode 2 of each LED chip 1 to the bonding region of the upper conductive pattern 13 in FIG. The wires 9a and 9b are, for example, gold wires. Thereby, the LED light-emitting device in which the four LED chips 1 are arranged in a line and mounted in a series circuit is configured. Of the conductive patterns 13, the bottom pattern in FIG. 1 is an anode, and the top pattern is a cathode.

The feature of the first embodiment is as follows.
The four LED chips 1 are arranged on the submount substrate 11 so that the first side 1a of each LED chip 1 and the first side 11a of the submount substrate 11 are parallel to each other with a space therebetween. The second side 1b and the second side 11b of the submount substrate 11 are mounted so as to be parallel to each other with a space therebetween. The four LED chips 1 are arranged in a line in which their first sides 1a are aligned on a straight line.
The pad electrode 7a on the first side 1a of the two pad electrodes 7a and 7b provided at the two diagonal corners of the upper surface of the LED chip 1 and the upper surface on the first side 11a side of the submount substrate 11 Between the bonding region of the provided conductive pattern 13, the wire 9 a is placed away from the first side 1 a in a direction perpendicular to the first side 1 a in a direction from the pad electrode 7 a in plan view. It was constructed so as to be in a direction inclined 15 to 40 degrees (inclination angle θ) (20 to 25 degrees in the illustrated example) in the direction.
A wire between the pad electrode 7b on the second side 1b side of the two pad electrodes 7a and 7b and the bonding region of the conductive pattern 13 provided on the upper surface on the second side 11b side of the submount substrate 11 9b is 15 to 40 degrees (inclination angle θ) in the direction in which the installation direction from the pad electrode 7b in plan view approaches the second side 1b with respect to the direction D perpendicular to the second side 1b (in the illustrated example) (20-25 degrees) It was constructed so that it was in the inclined direction.

  Thus, the construction direction of the wires 9a and 9b from the pad electrodes 7a and 7b in a plan view is a direction inclined by 15 to 40 degrees with respect to the first side 1a side or the direction perpendicular to the second side 1b. As a result, the width of the bonding region of the conductive pattern 13 for bonding the ends of the wires 9a and 9b can be reduced and the size of the submount substrate 11 can be reduced as compared with the conventional example 1 shown in FIG.

  The embodiment 2 shown in FIG. 3 is an LED light emitting device 20 in which eight LED chips 1 are mounted in a two-row arrangement / series two circuit on a submount substrate 21 having a minimum size necessary for mounting.

  The LED chip 1 used in the second embodiment is the same as the LED chip 1 used in the first embodiment. In FIG. 3, the four LED chips 1 in the left column are referred to as first LED chips, and the four LED chips 1 in the right column are referred to as second LED chips.

  The submount substrate 21 is a wiring substrate including an insulating and high thermal conductivity ceramic plate 22 (for example, aluminum nitride) and a conductive pattern 23 having a wiring pattern formed on the upper surface thereof, and has a rectangular shape in plan view. The first side 21a and the second side 21b that face each other in parallel are parallel to each other. The conductive patterns 23 are ten patterns arranged in two rows with five insulating layers 24 on the left and right sides, and the LED chips 1 are placed one by one on the lower eight patterns in FIG. The entire surface of each p-electrode 6 is joined electrically and thermally. Further, two wires 9a and 9b are laid and bonded from the two pad electrodes 7a and 7b of the n-electrode 2 of each LED chip 1 to the pattern of the upper adjacent conductive pattern 23 in FIG. Thus, an LED light emitting device is configured in which eight LED chips 1 are arranged in two rows and are mounted in series two circuits. Among the conductive patterns 23, the bottom two patterns in FIG. 3 are anodes, and the top two patterns are cathodes. Two patterns of anodes may be combined to form an anode common, or two patterns of cathodes may be combined to form a cathode common.

The feature of the second embodiment is as follows.
The four first LED chips 1 and the four second LED chips 1 are arranged on the submount substrate 21 with the first side 1 a of the first LED chip 1 and the first side 21 a of the submount substrate 21. The second side 1b of the first LED chip 1 and the first side 1a of the second LED chip 1 are parallel to each other with a chip interval, and the second side 1b of the second LED chip 1 is parallel. And the second side 21b of the submount substrate 21 are mounted so as to be parallel to each other with a space therebetween. The four first LED chips 1 are arranged in a line in which their first sides 1a are aligned on a straight line. Further, the four second LED chips 1 also form a row in which their first sides 1a are aligned on a straight line.
Of the two pad electrodes 7 a and 7 b provided at the two diagonal corners of the upper surface of the first LED chip 1, the pad electrode 7 a on the first side 1 a side and the first side 21 a side of the submount substrate 21 Between the bonding region of the conductive pattern 23 provided on the upper surface, the wire 9a is installed from the first side 1a in a direction perpendicular to the first side 1a so that the erected direction from the pad electrode 7a in a plan view is It was constructed so that it was in a direction inclined 15 to 40 degrees in the direction to leave.
-The pad electrode 7b on the second side 1b side of the two pad electrodes 7a, 7b provided at the two diagonal corners of the upper surface of the first LED chip 1 and the first interval between the chips of the submount substrate 21. Between the bonding region of the conductive pattern 23 provided on the upper surface near the LED chip 1, the wire 9 b is installed in a plan view from the pad electrode 7 b with respect to the second side 1 b at a right angle. It was constructed so as to be in a direction inclined 15 to 40 degrees in a direction approaching the second side 1b.
A second electrode electrode 7a on the first side 1a of the two pad electrodes 7a, 7b provided at two diagonal corners on the upper surface of the second LED chip 1 and the second chip interval of the submount substrate 21 in the chip interval. Between the bonding region of the conductive pattern 23 provided on the upper surface near the LED chip 1, the wire 9a is installed in a plan view from the pad electrode 7a in a direction perpendicular to the first side 1a. It was constructed so as to be in a direction inclined 15 to 40 degrees away from the first side 1a.
The pad electrode 7b on the second side 1b side of the two pad electrodes 7a and 7b provided at the two diagonal corners on the upper surface of the second LED chip 1 and the second side 21b side of the submount substrate 21 Between the bonding region of the conductive pattern 23 provided on the upper surface, the wire 9b is placed on the second side 1b so that the erection direction from the pad electrode 7b in plan view is perpendicular to the second side 1b. It was constructed so that it was in a direction inclined 15 to 40 degrees in the direction of approach.
-The first LED chip 1 and the second LED chip 1 constitute a parallel circuit. The four first LED chips 1 are connected in series, and the four second LED chips 1 are connected in series.

  In the second embodiment, as in the first embodiment, the erection direction of the wires 9a and 9b from the pad electrodes 7a and 7b in a plan view is in a direction perpendicular to the first side 1a side or the second side 1b. By the direction inclined by 15 to 40 degrees, the width of the bonding region of the conductive pattern 23 for bonding the ends of the wires 9a and 9b is made smaller than that of the conventional example 2 shown in FIG. The size can be reduced and the chip interval between two rows can be reduced.

  Example 3 shown in FIG. 4 is an LED light emitting device in which eight LED chips 1 are mounted in a two-row arrangement / series two circuit on a base substrate 31 also provided with a power receiving terminal for contacting a power supply terminal of a lighting fixture. 30.

  The LED chip 1 used in the third embodiment is the same as the LED chip 1 used in the first embodiment.

  The base substrate 31 is a wiring substrate including an insulating and high thermal conductivity ceramic plate 32 (for example, aluminum nitride) and a conductive pattern 33 having a wiring pattern formed on the upper surface thereof. The base substrate 31 has a rectangular shape in plan view. The first side 31a and the second side 31b that face each other are parallel to each other. The upper side which is the third side of the base substrate 31 is an attachment side to the lighting fixture. The conductive pattern 33 includes eight patterns arranged in four rows on the left and right sides with an insulating region 34 therebetween, and one relatively wide pattern in which the insulating region 34 is arranged on the eight patterns. The LED chips 1 are mounted one by one on the eight patterns, and the entire surface of each p-electrode 6 is electrically and thermally bonded. In FIG. 4, the four LED chips 1 in the left column are referred to as first LED chips, and the four LED chips 1 in the right column are referred to as second LED chips. Also, two wires 9a and 9b are laid and bonded from the two pad electrodes 7a and 7b of the n-electrode 2 of each LED chip 1 to the pattern of the upper adjacent conductive pattern 33 in FIG. Thus, an LED light emitting device is configured in which eight LED chips 1 are arranged in two rows and are mounted in series two circuits. Among the conductive patterns 33, the two lowermost patterns in FIG. 4 are the anode patterns 33a, and the uppermost one wide pattern is the cathode common pattern 33c.

  Also in the third embodiment, the features regarding the parallel arrangement of the LED chip 1 with respect to the base substrate 31 and the installation direction of the wires 9a and 9b are the same as those in the second embodiment. The size of the base substrate 31 can be made as small as possible, and the chip interval between two rows can be made as small as possible.

  Further, the feature of the third embodiment is that the common pattern of the conductive pattern 33 can be widened. That is, the cathode common pattern 33c, which is relatively wider than the other patterns, extends upward in FIG. 4 while remaining wide, and the cathode power receiving terminal 35c positioned at the center of the upper side, which is the attachment side. This is in contact with the central power supply terminal 36 of the lighting fixture. The anode pattern 33a on the left side extends upward on the left side with the insulating region 34 from the left column of the LED chip 1, and an anode power receiving terminal 35a located on the left side of the upper side, which is an attachment side. This is in contact with the left feeding terminal 36 of the lighting fixture. The anode pattern 33a on the right side extends upward on the right side with the insulating region 34 from the right column of the LED chip 1, and the extension end portion serves as the anode power receiving terminal 35a located on the right side of the upper side that is the attachment side. This is in contact with the right feeding terminal 36 of the lighting fixture.

  As described in the conventional example 3, even in the case where the power supply terminals 36 included in the mounting holder of the lighting fixture are arranged at equal intervals and the positions thereof are determined, in the third embodiment, the cathode common pattern 33c is formed on the LED light emitting device. By providing it at the center of the attachment side, the width of the cathode common pattern 33c can be increased, so that the electrical resistance can be reduced and the voltage drop can be reduced. In addition, there is a margin in pattern design and the insulating region 34 in the vicinity of the power supply terminal 36 can be expanded, so that safety against a short circuit is increased.

  In the fourth embodiment shown in FIG. 5, as in the third embodiment, the eight LED chips 1 are mounted in a two-row arrangement / series two circuit on the base substrate 41 having a power receiving terminal for contacting the power supply terminal of the lighting fixture. The LED light emitting device 40 is different from the third embodiment in that the anode common is used.

  The LED chip 1 used in the fourth embodiment is the same as the LED chip 1 used in the first embodiment.

  The base substrate 41 is a wiring substrate including an insulating and high thermal conductivity ceramic plate 42 (for example, aluminum nitride) and a conductive pattern 43 having a wiring pattern formed on the upper surface thereof. The base substrate 41 has a rectangular shape in plan view. The first side 41a and the second side 41b that face the left and right are parallel. The lower side that is the third side of the base substrate 41 is an attachment side to the lighting fixture. The conductive pattern 43 includes eight patterns arranged in four rows on the left and right sides with an insulating region 44 therebetween, and one relatively wide pattern arranged with the insulating region 44 under the eight patterns. One LED chip 1 is mounted on each of the lower six patterns of the eight, two LED chips 1 are mounted on one wide pattern, and the entire surface of each p electrode 6 is electrically and Thermally bonded. Further, two wires 9a and 9b are laid and bonded from the two pad electrodes 7a and 7b of the n-electrode 2 of each LED chip 1 to the pattern of the upper adjacent conductive pattern 43 in FIG. Thus, an LED light emitting device is configured in which eight LED chips 1 are arranged in two rows and are mounted in series two circuits. Of the conductive patterns 43, the bottom one wide pattern in FIG. 5 is the anode common pattern 43a, and the top two patterns are the cathode patterns 43c.

  Also in the fourth embodiment, the features regarding the parallel arrangement of the LED chip 1 with respect to the base substrate 41 and the installation direction of the wires 9a and 9b are the same as those in the second embodiment. For example, the size of 41 can be made as small as possible, or the chip interval between two rows can be made as small as possible.

  The anode common pattern 43a, which is relatively wider than the other patterns, extends downward in FIG. 5 while maintaining its width, and has an anode power receiving terminal 45a positioned at the center of the lower side where the extended end is the mounting side. This is in contact with the central power supply terminal 46 of the lighting fixture. The cathode pattern 43c on the left side extends downward on the left side with the insulating region 44 from the left column of the LED chip 1, and the cathode receiving terminal 45c located on the left side of the lower side whose extension end is the attachment side. This is in contact with the left power supply terminal 46 of the lighting fixture. The cathode pattern 43c on the right side extends downward on the right side with the insulating region 44 from the right column of the LED chip 1, and the extended end portion serves as a cathode power receiving terminal 45c located on the right side of the lower side that is the attachment side. This is in contact with the right feeding terminal 46 of the lighting fixture.

  Also in the fourth embodiment, for the same reason as in the third embodiment, the width of the anode common pattern 43a can be increased, so that the electrical resistance can be reduced and the voltage drop can be reduced. In addition, there is a margin in pattern design and the insulating region 44 near the power supply terminal 36 can be expanded, so that safety against a short circuit is increased.

  A fifth embodiment shown in FIGS. 6 and 7 is a vehicle headlamp 50 configured using the LED light emitting device 10 of the first embodiment.

  The vehicle headlamp 50 includes an LED package 51 that is mounted upward by mounting the LED light emitting device 10 of the first embodiment on a base substrate 52 with a power receiving terminal, and a rear side of the LED package (FIGS. 6 and 6). 7 on the left side) includes a substantially half parabolic reflector 58 extending around the LED chip 1 and a head lens 59 provided in front of the LED package (right side in FIGS. 6 and 7). It consists of The central portions of the four LED chips 1 are arranged at or near the focal point of the reflector 58, and light emitted upward or around from the light emitting surface of the LED chip 1 is reflected forward by the reflector 58, and this forward light is reflected. The head lens 59 collects light within a predetermined range.

  The base substrate 52 of the LED package 51 is a wiring substrate including a ceramic plate 53 (for example, aluminum nitride) and a conductive pattern 54 having a wiring pattern formed on the upper surface thereof. The conductive pattern 54 includes a central pattern for joining the submount substrate 11 of the LED light emitting device 10, a right cathode pattern for connecting the cathode of the LED light emitting device 10 by wire bonding, and an anode of the LED light emitting device 10 by wire bonding. A left anode pattern to be connected is provided with an insulating region 55 therebetween. A power supply terminal 56 is in contact with each of the cathode pattern and the anode pattern. A shell-like cover 57 surrounding the LED chip 1 is provided on the base substrate 52. When the emission color of the LED chip 1 is, for example, blue, for example, a yellow phosphor is contained in the resin applied to the surface of the LED chip 1, and white light is emitted to the outside.

In addition, the LED light emitting device 10 is arranged so that the perpendicular separation direction D with respect to the first side 1 a of the LED chip 1 is a rearward direction from the LED chip 1 toward the reflector 58. And as demonstrated in Example 1 (FIG. 1), the construction direction of the wire 9a from the pad electrode 7a on the first side 1a side of the LED chip 1 is the same as the perpendicular separation direction D with respect to the first side 1a. direction der inclined 15-40 ° in a direction away from the side 1a is, and the wire 9a is, the first side of the LED chip 1 of the next in the direction away from the first side 1a (upper neighboring in the figure) Citea Ru so as not perpendicular separating direction with respect to 1a. For this reason, the wire 9a does not enter the optical path from the LED chip 1 toward the reflector 58 toward the rear (particularly rearward and obliquely upward), and no shadow of the wire is generated. Therefore, a decrease in the amount of light due to the shadow of the wire can be prevented, and the appearance of the wire can be prevented from being deteriorated since the shadow of the wire is not visible from the outside.

  A sixth embodiment shown in FIGS. 8 and 9 is a vehicle headlamp 60 configured in the same manner as the fifth embodiment using the LED light emitting device 30 of the third embodiment.

  Also in the sixth embodiment, for the same reason as in the fifth embodiment, it is possible to prevent the light amount from being reduced due to the shadow of the wire, and it is possible to prevent the appearance of the wire from being deteriorated because the shadow of the wire is not visible from the outside. . Further, in the sixth embodiment, the four first LED chips 1 in the left row and the four second LED chips 1 in the right row are arranged so that the front-rear direction positions with respect to the focal point of the reflector 58 are different from each other. By selectively lighting the LED chip 1 and the second LED chip 1, the way of reflection by the reflector 58 can be changed to change the irradiation range of the headlamp.

  In addition, this invention is not limited to the said Example, In the range which does not deviate from the meaning of invention, it can change suitably and can be actualized.

DESCRIPTION OF SYMBOLS 1 LED chip 1a 1st edge | side 1b 2nd edge | side 7a Pad electrode 7b Pad electrode 9a Wire 9b Wire 10 LED light-emitting device 11 Submount board | substrate 11a 1st edge | side 11b 2nd edge | side 12 Ceramic board 13 Conductive pattern 20 LED light-emitting device 21 Submount Substrate 21a First side 21b Second side 22 Ceramic plate 23 Conductive pattern 30 LED light emitting device 31 Base substrate 31a First side 31b Second side 32 Ceramic plate 33 Conductive pattern 33a Anode pattern 33c Cathode common pattern 40 LED light emitting device 41 Base substrate 41a First side 41b Second side 42 Ceramic plate 43 Conductive pattern 43a Anode common pattern 43c Cathode pattern 50 Vehicle headlamp 58 Reflector 60 Vehicle headlamp

Claims (1)

The LED chip in which the first side and the second side facing each other are parallel to each other on the substrate in which the first side and the second side facing each other are parallel to each other, the first side and the first side are spaced apart from each other. Mounted in parallel so that the second side and the second side are parallel to each other with a space between them, and a plurality of the LED chips are mounted so that the first sides are aligned in a straight line And a plurality of the LED chips constitute a series circuit,
Between the pad electrode on the first side of the two pad electrodes provided at the two diagonal corners of the upper surface of the LED chip and the bonding area of the conductive pattern provided on the upper surface on the first side of the substrate In addition, the wire is installed so that the installation direction from the pad electrode in plan view is a direction inclined 15 to 40 degrees away from the first side with respect to the perpendicular separation direction with respect to the first side, and The wire does not extend in a direction perpendicular to the first side of the adjacent LED chip that is oriented away from the first side,
Between the pad electrode on the second side of the two pad electrodes and the bonding area of the conductive pattern provided on the upper surface on the second side of the substrate, a wire is installed from the pad electrode in plan view. Using an LED light emitting device constructed so that the direction is a direction inclined by 15 to 40 degrees in a direction approaching the second side with respect to the direction perpendicular to the second side ,
The LED light emitting device is arranged upward so that light can be emitted upward or around from the upper surface of the LED chip,
A reflector extending around the LED chip is provided behind the LED light-emitting device so as to reflect the upward or ambient light forward,
By arranging the LED light-emitting device so that the direction perpendicular to the first side of the LED chip is the rearward direction from the LED chip to the reflector, the wire laid from the pad electrode on the first side becomes the LED chip. Vehicle headlamps that do not enter the rear light path from the camera to the reflector.

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