JP7390942B2 - LED light emitting device - Google Patents

Description

The present invention relates to a color adjustable LED light emitting device.

A light emitting section is provided on a single mounting board, in which a plurality of fine first light emitting regions that emit light in a first color and a plurality of fine second light emitting regions that emit light in a second color are assembled, and the first light emitting section There are known LED light emitting devices capable of dimming and color adjustment, which adjust the amount of light emitted from the entire region and the amount of light emitted from the entire second light emitting region to obtain desired brightness and color of emitted light (for example, Patent Document Figure 1).

Therefore, referring to FIG. 1 of Patent Document 1 and FIG. 13 of the drawings attached to the present application, the LED light emitting device (adjustable color LED lighting device) shown in FIG. 13 will be described. Note that () indicates terms in Patent Document 1. The sign has been changed when quoting.

FIG. 13 is a plan view of an LED light emitting device 100 shown as a conventional technique. As shown in FIG. 13, the mounting board 103 (substrate) has negative power supply electrodes 105a and 105b (cathode electrodes), positive power supply electrodes 106a and 106b (anode electrode), and power supply electrodes 105a and 105b on the top surface. It includes wiring electrodes 115a and 115b (cathode wiring) to be connected, and wiring electrodes 116a and 116b (anode wiring) to be connected to the power supply electrodes 106a and 106b. In addition, a large number of first LED dies 111 (LED chips) and second LED dies 112 (LED chips) are mounted on the light emitting section 102 (light emitting surface), which is the area inside the dam 108 formed on the upper surface of the mounting board 103. has been done. The first LED die 111 and the second LED die 112 are coated with fluorescent resin and arranged in a triangular arrangement.

The first LED die 111 is connected in 8 series x 8 parallel configurations to form a first circuit. The second LED die 112 is connected in 9 series x 9 parallel configurations to form a second circuit. The first circuit and the second circuit are each independently driven. Further, the first light emitting region including the first LED die 111 that emits blue light and the fluorescent resin emits white light with a high color temperature. The second light emitting region including the second LED die 112 emits light in amber color or white color with a low color temperature. That is, the LED light emitting device 100 arranges the first light emitting region and the second light emitting region in a triangular manner, maintains high color mixing properties, and adjusts the currents supplied to the first circuit and the second circuit to create the entire first light emitting region and the second light emitting region. The light emission amount (luminous flux) of the entire second light emitting region and its ratio are changed to obtain light with desired intensity and color temperature.

In the LED light emitting device 100, the first LED die 111 is a face-up mounting LED element having an anode and a cathode on the top surface, and the second LED die 112 has an anode on the top surface and a cathode on the bottom surface (or a cathode electrode on the top surface). This is a vertical electrode LED element with an anode on the bottom surface. That is, when the first LED dies 111 are connected in series, the first LED dies 111 are connected to each other with a wire. On the other hand, when the second LED dies 112 are connected in series, an anode (or cathode) provided on the top surface of one second LED die 112 and an anode (or cathode) provided on the top surface of one second LED die 112 and a bottom surface of the other second LED die 112 mounted A wire is used to connect the cathode (or anode) provided to the wiring electrode (to which it is connected).

JP2019-91648A (Figure 1)

However, in the LED light emitting device 100 shown in FIG. 13, when trying to bring the first LED die 111 and the second LED die 112 closer together with the aim of downsizing, the wiring formed on the mounting board 103 for mounting the second LED die 112 Electrodes get in the way. That is, since the wiring electrode requires a space for wire bonding, there is a problem in the LED light emitting device 100 that the first LED die 111 and the second LED die 112 cannot be placed sufficiently close to each other. On the other hand, if the second LED die 112 is replaced with an LED element for face-up mounting in order to eliminate the need for wiring electrodes, the wires connecting the first LED dies 111 and the wires connecting the second LED dies 112 will be A problem arises in that they partially intersect (here, "intersect" refers to a state in which they are visually recognized as intersecting when viewed two-dimensionally, but are not short-circuited three-dimensionally. The same applies hereinafter).

When wires intersect, at least one of the intersecting wires is forced to take an irregular shape, often rectangular in side view. For this reason, problems such as short circuits between wires and disconnection of the wires themselves are likely to occur.

The present invention has been made in view of the above-mentioned problems, and it is possible to adjust the light and color, while also ensuring that there is no wire crossing even if the LED dies are placed close to each other in an arrangement that allows for high color mixing. Provides an LED light emitting device.

In order to solve the above problems, the LED light emitting device of the present invention includes a mounting board, a plurality of first light emitting regions that emit light in a first color, and a plurality of second light emitting regions that emit light in a second color , arranged in a checkerboard pattern. In the LED light emitting device , the first light emitting region includes a first LED die mounted on the mounting substrate, and a first fluorescent resin layer covering an upper surface of the first LED die,
The second light emitting region includes a second LED die mounted on the mounting board, and a second fluorescent resin layer covering an upper surface of the second LED die , and the first fluorescent resin layer and the second fluorescent resin layer include: The LED die is excited by a first LED die and a second LED die, respectively, and the first LED die is mounted face-up on the mounting board, and the second LED die is mounted face-down on the mounting board.

The light emitting section of the LED light emitting device of the present invention is composed of an aggregate of a first light emitting region and a second light emitting region, which are minute light emitting regions. In this light-emitting section, the first light-emitting region and the second light-emitting region are arranged such that the first light-emitting region and the second light-emitting region are close to each other when viewed in plan, and the first light-emitting region and the second light-emitting region are close to each other. They are arranged so that they are not adjacent to each other. The first light emitting region includes a first fluorescent resin layer, and the first fluorescent resin layer is excited by the first LED die. Similarly, the second light emitting region includes a second fluorescent resin layer, and the second fluorescent resin layer is excited by the second LED die. Further, the first LED dies are mounted face-up on the mounting board and connected to each other with wires. The second LED dies are mounted face-down on the mounting board and are connected to each other via wiring electrodes formed on the mounting board.

The combined area of the first light emitting area and the second light emitting area may have an octagonal outer edge.

The first LED die may be individually covered with a dome-shaped first fluorescent resin layer.

The second LED die may be individually covered on top with the second fluorescent resin layer having a dome shape.

A die bonding material may be provided to connect the first LED die and the mounting board, and the die bonding material may cover the surface of the mounting board in a gap between the first LED die and the second LED die.

Based on the surface of the mounting board, the top surface of the first LED die is higher than the top surface of the second LED die, and the top surface of the second fluorescent resin layer is lower than the top surface of the first LED die. It may be higher than the top surface.

The first LED die may be mounted face-up on the second LED die.

As described above, in order to achieve high color mixing properties, the LED light emitting device of the present invention has the first light emitting region and the second light emitting region close to each other, but the first light emitting regions and the second light emitting regions are not adjacent to each other. I have to. That is, while the first LED die serving as the first light source of the first light emitting area and the second LED die serving as the first light source of the second light emitting area are brought close to each other, the first LED die and the second LED die are placed so as not to be adjacent to each other. Although the 1st LED die and the 2nd LED die are mounted on a single mounting board, the 1st LED die is mounted face-up and the 2nd LED die face-down, so there is no need to cross wires. can.

Therefore, in the LED light emitting device of the present invention, which is capable of dimming and color adjustment, even if the LED dies are placed close to each other in an arrangement that allows for high color mixing, there is no crossing of wires, and problems such as short circuits and disconnections related to wire bonding are avoided. can be resolved.

1 is a plan view of an LED light emitting device shown as a first embodiment of the present invention. 2 is a plan view of a first LED die included in the LED light emitting device shown in FIG. 1. FIG. 2 is a bottom view of a second LED die included in the LED light emitting device shown in FIG. 1. FIG. 2 is a plan view of the LED light emitting device shown in FIG. 1. FIG. 2 is a circuit diagram of the LED light emitting device shown in FIG. 1. FIG. FIG. 2 is a partial perspective view of the LED light emitting device shown in FIG. 1. FIG. 2 is a partial cross-sectional view of the LED light emitting device shown in FIG. 1. FIG. 2 is a flowchart of a method for manufacturing the LED light emitting device shown in FIG. 1. FIG. FIG. 9 is an explanatory diagram of the process shown in FIG. 8; It is a partial sectional view of the LED light emitting device shown as 2nd Embodiment of this invention. It is a partial sectional view of an LED light emitting device shown as a 3rd embodiment of the present invention. It is a partial sectional view of an LED light emitting device shown as a 4th embodiment of the present invention. 1 is a plan view of an LED light emitting device shown as a conventional technique.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 12. In the description of the drawings, the same or equivalent elements are given the same reference numerals, and redundant description will be omitted. For the sake of explanation, the scale of the members has been changed as appropriate. Items in parentheses indicate matters specifying the invention in the claims.

(First embodiment)
FIG. 1 is a plan view of an LED light emitting device 10 shown as a first embodiment of the present invention. As shown in FIG. 1, the LED light emitting device 10 is a so-called COB (chip on board) module, and includes a mounting board 13. Power supply electrodes 18a, 18b, 19a, and 19b are formed at two corners of the mounting board 13. Further, an annular dam 15 is formed in a region inside the power supply electrodes 18a, 18b, 19a, and 19b. A transparent resin layer 16b exists in a circular region inside the dam 15 (hereinafter referred to as "light emitting section 15a"). A first light emitting region 11a and a second light emitting region 12a are arranged in a checkered pattern in a region included in the light emitting portion 15a and having an octagonal outer edge. That is, in the LED light emitting device 10, in the light emitting part 15a, the first light emitting region 11a and the second light emitting region 12a are arranged close to each other, but the first light emitting regions 11a and the second light emitting regions 12a are not arranged adjacent to each other.

Here, in FIG. 1, the first light emitting region 11a and the second light emitting region 12a are illustrated as squares for convenience. That is, although the first light emitting region 11a and the second light emitting region 12a have unclear boundaries (see FIG. 7), in FIG. 1, the first LED die 11b (see FIG. 7) and It is drawn to match the second LED die 12b (see FIG. 7) included in the second light emitting region 12a. That is, as shown in FIG. 7, the first light emitting region 11a includes the first LED die 11b and the first fluorescent resin layer 11c, and the second light emitting region 12a includes the second LED die 12b and the second fluorescent resin layer 12c. Among them, when the LED light emitting device 10 is not lit, the first light emitting region 11a is recognized as the first fluorescent resin layer 11c, and the second light emitting region 12a is recognized as the second fluorescent resin layer 12c. On the other hand, when the LED light emitting device 10 is turned on, the first light emitting region 11a and the second light emitting region 12a are square with rounded corners, the peripheral portions are blurred and widened, and are visually recognized as rounded shapes. Further, in FIG. 1, the wires 14a (see FIG. 3) connecting the first LED dies 11b are visible but not shown.

FIG. 2 is a plan view of the first LED die 11b included in the first light emitting region 11a. The first LED die 11b has a planar size of 0.6 mm x 0.6 mm, and is a blue light emitting diode for face-up mounting.For wire bonding, the first LED die 11b has an anode 21a at the upper left corner of the top surface and a cathode 22a at the lower right center. We are prepared. The anode 21a is formed on the upper surface of the P layer 23a, and the cathode 22a is formed on the upper surface of the N layer 24a exposed from the P layer 23a.

FIG. 3 is a bottom view of the second LED die 12b included in the second light emitting region 12a. The second LED die 12b is a face-down blue light emitting diode with a planar size of 0.6 mm x 0.6 mm, and is connected to the wiring electrode 14b (see FIG. 7) formed on the upper surface of the mounting board 13. An anode 21b and a cathode 22b are provided on the bottom surface. The anode 21b has a substantially square shape with the upper left corner of the bottom cut out, and is formed to occupy almost the entire surface of the P layer 23b. The cathode 22b is formed on the surface of the N layer 24b exposed from the P layer 23b at the upper left corner of the bottom surface.

FIG. 4 shows a transparent resin layer 16b, a first fluorescent resin layer 11c, a second fluorescent resin layer 12c, a die-bonding material 16a (see FIG. 7) and FIG. 2 is a plan view of the LED light emitting device 10 with the dam 15 (see FIG. 1) removed. As shown in FIG. 4, the first LED die 11b and the second LED die 12b are arranged in a matrix so as to form a checkered pattern as a whole. Note that, as described above, since the second LED die 12b is for face-down mounting, the wiring electrode 14b connected to the anode 21b and cathode 22b of the second LED die 12b is formed on the upper surface of the mounting board 13 (see FIG. and Figure 7). However, in FIG. 4, the specific shape of the wiring electrode 14b is not shown, but the connection relationship is shown by dotted lines.

As shown in FIG. 4, on the mounting board 13, in addition to the power supply electrodes 18a, 18b, 19a, and 19b, there are wiring electrodes 18a1, 18b1, 19a1, and 19b1 extending in an arc shape from the power supply electrodes 18a, 18b, 19a, and 19b, respectively. and a relay wiring electrode 19a2 are formed. Protective Zener diodes 17a and 17b are arranged between the wiring electrode 18a1 and the wiring electrode 19a2, and between the power supply electrode 19b and the wiring electrode 18b1, respectively. Zener diode 17a is connected to power supply electrode 18a via wire 14a and wiring electrode 18a1, and also connected to power supply electrode 19a through wire 14a, wiring electrode 19a2, and another wire 14a. Similarly, the Zener diode 17b is connected to the power supply electrode 19b via the wire 14a, and is also connected to the power supply electrode 18b via the wire 14a and the wiring electrode 18b1. Parts of power supply electrodes 18a, 18b, 19a, 19b, wiring electrodes 18a1, 18b1, 19a1, 19a2, 19b1, Zener diodes 17a, 17b, part of wire 14a, and part of wiring electrode 14b are covered with dam 15. (See Figure 1).

As mentioned above, in FIG. 4, the wire 14a is shown as a solid line, and the wiring electrode 14b is shown as a dotted line in order to make the connection easier to understand. As shown in FIG. 4, the first LED dies 11b and the first LED dies 11b and the wiring electrodes 18a1 and 19a1 are connected by wires 14a. Similarly, the second LED dies 12b and the second LED dies 12b and the wiring electrodes 18b1 and 19b1 are connected by a wiring electrode 14b formed on the mounting board 13. The wire 14a and the wiring electrode 14b intersect at a portion when viewed from above.

Sixty first LED dies 11b and sixty second LED dies 12b are mounted on the light emitting section 15a. The 60 first LED dies 11b are connected in series, 12 at a time, to form five first LED rows 11d (see FIG. 5), and the five first LED rows 11d are connected in parallel (12 series x 5 parallel). Similarly, the 60 second LED dies 12b are connected in series, 12 at a time, to form five second LED rows 12d (see FIG. 5), and the five second LED rows 12d are connected in parallel ( 12 series x 5 parallel). The first LED die 11b belonging to the first LED row 11d is arranged in a diagonal manner while bending from the upper left to the lower right in the figure. Similarly, the second LED die 12b belonging to the second LED row 12d is also arranged in a diagonal manner while bending from the upper left to the lower right in the figure. In consideration of ease of handling, the LED light emitting device 10 has a circular light emitting region 15a, and the number of series stages of the first LED die 11b and the second LED die 12b included in the first LED row 11d and the second LED row 12d is 12. The first LED row 11d and the second LED row 12d can be lit at a relatively low voltage (for example, 2.7 (V) x 12 (stages) = 32.4 (V)).

In the first LED row 11d, the anode 21a (see FIG. 2) included in the first LED die 11b arranged at the upper end in the figure is connected to the wiring electrode 18a1, and is arranged at the lower end in the figure. The cathode 22a (see FIG. 2) included in the first LED die 11b is connected to the wiring electrode 19a1. Similarly, in the second LED row 12d, the cathode 22b (see FIG. 3) included in the second LED die 12b arranged at the upper end in the figure is connected to the wiring electrode 19b1, and is connected to the lower end in the figure. An anode 21b (see FIG. 3) included in the arranged second LED die 12b is connected to the wiring electrode 18b1.

FIG. 5 is a circuit diagram of the LED light emitting device 10. The LED light emitting device 10 includes a first circuit 11e that emits light as a first color at a high color temperature (for example, 5000K), and a second circuit 12e that emits light as a second color at a low color temperature (for example, 3000K).

As shown in FIG. 5, in the first circuit 11e, 12 first LED dies 11b are connected in series, and 5 first LED arrays 11d are connected in parallel (12 series x 5 parallel). The anode 21a (see FIG. 2) of the first LED die 11b included in the first LED row 11d is connected to the power supply electrode 18a via the wiring electrode 18a1. The cathode 22a (see FIG. 2) of the first LED die 11b in the final stage included in the first LED row 11d is connected to the power supply electrode 19a via the wiring electrode 19a1. A protective Zener diode 17a is connected to the wiring electrodes 18a1 and 19a1.

Similarly, in the second circuit 12e, 12 second LED dies 12b are connected in series, and 5 second LED rows 12d are connected in parallel (12 series x 5 parallel). The anode 21b (see FIG. 3) of the first-stage second LED die 12b included in the second LED row 12d is connected to the power supply electrode 18b via the wiring electrode 18b1. The cathode 22b (see FIG. 3) of the second LED die 12b in the final stage included in the second LED row 12d is connected to the power supply electrode 19b via the wiring electrode 19b1. A protective Zener diode 17b is connected to the wiring electrodes 18b1 and 19b1.

FIG. 6 is an enlarged partial perspective view of a portion where the wire 14a and the wiring electrode 14b intersect in plan view in the light emitting section 15a included in the LED light emitting device 10 shown in FIG. In addition, in FIG. 6, in order to simplify the illustration, the wires 14a are arranged from the upper left to the lower right of the figure, and the wiring electrodes 14b are arranged from the lower left to the upper right of the figure. There is no part corresponding to this connection state.) Further, similarly to FIG. 3, the transparent resin layer 16b, the first fluorescent resin layer 11c, the second fluorescent resin layer 12c, and the die bonding material 16a (see FIG. 7) are depicted in a state in which they have been removed.

FIG. 6 shows the surface of the mounting board 13 on which two first LED dies 11b and two second LED dies 12b are mounted. The first LED die 11b is die-bonded to the mounting board 13 and connected to each other by a wire 14a. The wire 14a is first bonded to the cathode 22a (see FIG. 2) located at the center of the first LED die 11b, and second bonded to the anode 21a (see FIG. 2) located at the upper left corner. The second LED die 12b is mounted such that the ends of two wiring electrodes 14b are connected to an anode 21b (see FIG. 3) and a cathode 22b (see FIG. 3), respectively. The wiring electrode 14b drawn in the center of the figure connects the cathode 22b of the second LED die 12b at the bottom left of the figure and the anode 21b of the second LED die 12b at the top right of the figure.

FIG. 7 is a partial cross-sectional view of the LED light emitting device 10, showing main parts along line AA' in FIG. FIG. 7 shows two first light emitting regions 11a and two second light emitting regions 12a. Note that in FIG. 7, the wire 14a, the wiring electrode 14b, the anode 21b, and the cathode 22b are illustrated in a simplified manner. That is, the wires 14a and the wiring electrodes 14b that run diagonally as shown in FIG. 3 are depicted as being arranged parallel to the line AA' in FIG. I have to.

As shown in FIG. 7, the bottom surface of the first LED die 11b is bonded to the top surface of the mounting board 13 with a die bonding material 16a. Furthermore, the die bonding material 16a creeps up and covers the side surfaces of the first LED die 11b and the second LED die 12b, and also covers the surface of the mounting board 13 in the gap between the first LED die 11b and the second LED die 12b. The die bonding material 16a contains reflective fine particles, and can ensure a sufficient thickness (for example, 30 to 50 μm) for light shielding at a position of about half the height on the side surfaces of the first LED die 11b and the second LED die 12b. Do it like this. The anode 21b and cathode 22b included in the second LED die 12b are connected to one wiring electrode 14b and the other wiring electrode 14b, respectively. This connection is made with solder, eutectic or anisotropic conductive adhesive.

The first fluorescent resin layer 11c covers the top and side surfaces of the first LED die 11b, forming a dome shape (bowl shape) with a curved top. Similarly, the second fluorescent resin layer 12c also covers the top and side surfaces of the second LED die 12b, forming a dome shape (bowl shape) with a curved top. The first fluorescent resin layer 11c and the die bonding material 16a that cover the side surface of the first LED die 11b suppress the light emitted from the first LED die 11b from the side surface of the first LED die 11b. Similarly, the second fluorescent resin layer 12c and the die bonding material 16a that cover the side surface of the second LED die 12b suppress the light emitted from the second LED die 12b from the side surface of the second LED die 12b. The transparent resin layer 16b covers the die bonding material 16a, the first fluorescent resin layer 11c, and the second fluorescent resin layer 12c from above, and seals them.

The mounting board 13 is made of white ceramics whose base material is alumina. On the upper surface of the mounting board 13, wiring electrodes 14b, 18a1, 18b1, 19a1, 19a2, 19b1 and power supply electrodes 18a, 18b, 19a, 19b are formed, which are made of a metal film in which Ni and Au are laminated on Cu ( (See Figure 3). The die-bonding material 16a is an adhesive material in which reflective fine particles made of Ag or titanium oxide are kneaded into a resin. The dam 15 is made of white silicone resin kneaded with fine particles of titanium oxide, and has a thickness of 0.7 to 1.0 mm and a height of 0.5 to 0.8 mm.

The first fluorescent resin layer 11c has a thickness of about 0.5 mm and is made of a green-emitting phosphor (for example, Lu ₃ Al ₅ O ₁₂ :Ce) and a red-emitting phosphor (for example, CaAlSiN ₃ :Eu). Contains. The color of the emitted light from the first light emitting region 11a has a color temperature of about 5000K due to the blue light emitted by the first LED die 11b and the light emitted from the first fluorescent resin layer 11c. The second fluorescent resin layer 12c has a thickness of about 0.5 mm and is made of a green-emitting phosphor (for example, Lu ₃ Al ₅ O ₁₂ :Ce) and a red-emitting phosphor (for example, CaAlSiN ₃ :Eu). However, the concentration and ratio of the phosphor is different from that of the first fluorescent resin layer 11c. The color of the emitted light from the second light emitting region 12a has a color temperature of about 3000K due to the blue light emitted by the second LED die 12b and the light emitted from the second fluorescent resin layer 12c.

Next, a method for manufacturing the LED light emitting device 10 will be described with reference to FIGS. 8 and 9. FIG. 8 is a flowchart showing the manufacturing steps included in the method for manufacturing the LED light emitting device 10, and FIG. 9 is an explanatory diagram of the manufacturing steps shown in the flowchart of FIG. Note that the members shown in FIGS. 1 to 7 will be cited without special instructions.

As shown in FIG. 8, the method for manufacturing the LED light emitting device 10 includes a preparation step 31 for preparing the mounting board 13, the first LED die 11b, the second LED die 12b, etc., and a face-down step for mounting the second LED die 12b on the mounting board 13. A mounting step 32, a die bonding step 33 of bonding the first LED die 11b and Zener diodes 17a, 17b to the mounting board 13 with a die bonding material 16a, a wire bonding step 34 of electrically connecting the first LED dies 11b, etc. with wires 14a, A dam forming step 35 in which a dam 15 is formed on the mounting board 13 so as to surround a set of the first LED die 11b and the second LED die 12b, and a first fluorescent step in which the upper part of the first LED die 11b is covered with a first fluorescent resin layer 11c. A resin coating step 36, a second fluorescent resin coating step 37 of coating the upper part of the second LED die 12b with a second fluorescent resin layer 12c, and a transparent resin coating step 38 of coating the inner area of the dam 15 with a transparent resin layer 16b. include.

In FIG. 9, in order to explain each process shown in FIG. 8, a cross section of the LED light emitting device 10 in the process of being manufactured is schematically drawn. Note that the LED light emitting device 10 may be manufactured using a method in which the first LED die 11b and the second LED die 12b are mounted on a separately separated mounting board 13, and various electronic components and resins are placed on the top surface of the mounting board 13. It is possible to manufacture the LED light emitting device 10 by arranging various electronic components and resins on a large-sized board, which can be diced into pieces to obtain a large number of mounting boards 13, and finally by cutting the large-sized board into pieces to obtain the LED light emitting device 10. It's okay. Although the latter method is suitable for mass production, in FIG. 9, for simplicity, the method for manufacturing the LED light emitting device 10 will be described using the former method. Further, in FIGS. 9A to 9H, a set of 60 first LED dies 11b and 60 second LED dies 12b is representatively illustrated with only one each.

FIG. 9A is an explanatory diagram of the preparation step 31. In the preparation step 31, the mounting board 13, the first LED die 11b, the second LED die 12b, and the Zener diodes 17a and 17b are prepared. The mounting board 13 is made of white ceramics whose base material is alumina. On the upper surface of the mounting board 13, there are formed wiring electrodes 14b, 18a1, etc., a power supply electrode 18a, etc. made of a metal film in which Ni and Au are laminated on Cu (see FIG. 3). The first LED die 11b includes a semiconductor layer (light emitting layer) on the top surface of the sapphire substrate, and the second LED die 12b includes a semiconductor layer (light emitting layer) on the bottom surface of the sapphire substrate. The Zener diodes 17a, 17b are smaller than the first LED die 11b and the second LED die 12b.

FIG. 9(b) is an explanatory diagram of the face-down mounting process 32. In the face-down mounting step 32, first, solder paste is printed on the portion of the wiring electrode 14b to be connected, and after the second LED die 12b is temporarily bonded, the final connection is performed in a reflow oven. In addition to solder, gold-tin eutectic or anisotropic adhesive can be used for connection.

FIG. 9C is an explanatory diagram of the die bonding process 33. In the die bonding step 33, the first LED die 11b and the Zener diodes 17a, 17b are bonded to the mounting board 13 using a die bonding material 16a. Note that before mounting the first LED die 11b and the Zener diodes 17a, 17b on the mounting board 13, a die bonding material 16a is applied in advance to the positions where each element is to be arranged. Thereafter, each element is placed in a predetermined position using a picker. At this time, the amount of the die bonding material 16a is adjusted, and the die bonding material 16a is made to protrude from the bottom surface of the first LED die 11b during die bonding, and a portion of the die bonding material 16a is made to creep up the side surfaces of the first LED die 11b and the second LED die 12b. In parallel with this, the space between the adjacent first LED die 11b and second LED die 12b is covered with a die bonding material 16a. Finally, the LED light emitting device 10 is heated to harden the die bonding material 16a. At this time, the distance between the first LED die 11b and the second LED die 12b is 0.1 to 0.4 mm.

FIG. 9(d) is an explanatory diagram of the wire bonding process 34. In the wire bonding process 34, the first LED die 11b is bonded to each other, the first LED die 11b and the wiring electrodes 18a1, 19a1, the Zener diode 17a and the power supply electrode 18a and the wiring electrode 19a2, the wiring electrode 19a2 and the power supply electrode 19a, and the Zener diode 17b and the power supply electrode. 18b and the wiring electrode 19b1 are electrically connected by a wire 14a. Note that, regarding the wire 14a, only the vicinity of the first LED die 11b is drawn, and other parts are omitted.

FIG. 9(e) is an explanatory diagram of the dam forming step 35. In the dam forming step 35, the dam 15 is formed on the mounting board 13 so as to surround the set of the first LED die 11b and the second LED die 12b. The dam 15 is made of white silicone resin, and has a thickness of 0.7 to 1.3 mm and a height of 0.5 to 0.8 mm. Further, the dam 15 is formed by discharging white silicone resin with high viscosity (or thixotropy) from the nozzle while moving the nozzle of the dispenser. At this time, the Zener diodes 17a and 17b are embedded in the dam 15. Similarly, a portion of the wire 14a connecting the wiring electrodes 18a1, 18b1, 19a1, 19a2, 19b1 and the power supply electrodes 18a, 18b, 19a, 19b and the first LED die 11b is also embedded in the dam 15. Finally, the LED light emitting device 10 is heated to harden the dam 15.

FIG. 9(f) is an explanatory diagram of the first fluorescent resin coating step 36. In the first fluorescent resin coating step 36, a first fluorescent resin is applied to the upper part of the first LED die 11b to form a first fluorescent resin layer 11c. The first fluorescent resin is a silicone resin containing a phosphor that emits green light (for example, Lu ₃ Al ₅ O ₁₂ :Ce) and a phosphor that emits red light (for example, CaAlSiN ₃ :Eu). Spot printing is performed on the upper part of the first LED die 11b by the nozzle. The first fluorescent resin layer 11c produced by spot printing has a maximum thickness of about 0.5 mm and has a dome shape. The emitted light color of the first light emitting region 11a including the first fluorescent resin layer 11c is about 5000K due to the blue light emitted by the first LED die 11b and the light emitted by the first fluorescent resin layer 11c.

FIG. 9(g) is an explanatory diagram of the second fluorescent resin coating step 37. In the second fluorescent resin coating step 37, a second fluorescent resin is applied to the upper part of the second LED die 12b to form a second fluorescent resin layer 12c. The second fluorescent resin is also a silicone resin containing a phosphor that emits green light (for example, Lu ₃ Al ₅ O ₁₂ :Ce) and a phosphor that emits red light (for example, CaAlSiN ₃ :Eu). Spot printing is performed on the upper part of the second LED die 12b by the nozzle. The second fluorescent resin layer 12c produced by spot printing has a maximum thickness of about 0.5 mm and has a dome shape. The emitted light color of the second light emitting region 12a including the second fluorescent resin layer 12c is approximately 3000K due to the blue light emitted by the second LED die 12b and the light emitted by the second fluorescent resin layer 12c.

FIG. 9(h) is an explanatory diagram of the transparent resin coating step 38. In the transparent resin coating step 38, the inner region of the dam 15 is filled with transparent resin to form the transparent resin layer 16b. The transparent resin is a transparent silicone resin that has low viscosity before hardening, and a dispenser is used for filling. After filling, the transparent resin is cured by heating.

In addition, in the first fluorescent resin coating step 36, the first fluorescent resin was applied by spot printing on the upper part of the first LED die 11b. Similarly, in the second fluorescent resin coating step 37, the second fluorescent resin was applied by spot printing on the upper surface of the second LED die 12b. However, the application method is not limited to spot printing; for example, spray printing using a mask may be used instead of spot printing. In either method, after coating, the first fluorescent resin and the second fluorescent resin are formed into a dome shape by surface tension.

The LED light emitting device 10 described with reference to FIGS. 1 to 9 includes an aggregate of a first light emitting region 11a and a second light emitting region 12a, which are minute light emitting regions. In the light emitting section 15a, the first light emitting region 11a and the second light emitting region 12a are adjacent to each other in the vertical and horizontal directions when viewed from above, and are arranged in a checkered pattern. The first light emitting region 11a includes one first LED die 11b and emits light at approximately 5000K (first color). Similarly, the second light emitting region 12a includes one second LED die 12b and emits light at approximately 3000K (second color). The first fluorescent resin layer 11c is formed by spot printing on the top surface of the first LED die 11b and the side surface near the top surface, and has a dome shape with a curved top surface. The same applies to the second LED die 12b.

In this LED light emitting device 10, the current flowing through the first circuit 11e and the current flowing through the second circuit 12e are individually supplied, so that the color of the emitted light can be adjusted. In other words, the luminance of the first circuit 11e (the luminous flux of all the first light emitting regions 11a constituting the first circuit 11e) and the luminance of the second circuit 12e (the luminous flux of all the second light emitting regions 12a constituting the second circuit 12e) Since the luminous flux (luminous flux) can be controlled independently, the LED light emitting device 10 can obtain an emitted light color between 3000K and 5000K at any brightness.

As described above, the light emitting section 15a of the LED light emitting device 10 is composed of an aggregate of the first light emitting region 11a and the second light emitting region 12a, which are minute light emitting regions. In this light emitting section 15a, the first light emitting region 11a and the second light emitting region 12a are arranged in a checkered pattern. The first LED die 11b included in the first light emitting region 11a is mounted face-up on the mounting board 13 and connected to each other by wires 14a. The second LED die 12b included in the second light emitting region 12a is mounted face-down on the mounting board 13 and connected to each other through wiring electrodes 14b formed on the mounting board 13. In other words, even if the first LED die 11b and the second LED die 12b are arranged in a checkerboard pattern, since the first LED die 11b is mounted face-up and the second LED die 12b is mounted face-down, it is possible to eliminate the crossing of the wires 14a. can.

Therefore, even if the first LED die 11b and the second LED die 12b are placed close to each other in an arrangement that allows for high color mixing, the LED light emitting device 10 capable of dimming and color adjustment does not require wire bonding by eliminating the intersection of the wires 14a. Problems such as short circuits and disconnections can be eliminated.

Note that the desired luminescent color may not be achieved only by adjusting the fluorescent resin. For example, the first color (spectrum) that is the emission color of the first light emitting region 11a may not be achieved only by adjusting the first fluorescent resin layer 11c. At this time, the first LED die 11b may be a near-ultraviolet light emitting LED. In this way, the first fluorescent resin layer 11c comes to contain blue phosphor, and the spectrum of blue light becomes thicker and approaches natural light.

Furthermore, in the LED light emitting device 10, the first fluorescent resin layer 11c and the second fluorescent resin layer 12c were at the same height. At this time, the concentration and ratio of the same two types of phosphors are adjusted between the first fluorescent resin layer 11c and the second fluorescent resin layer 12c, and the emitted light colors of the first light emitting region 11a and the second light emitting region 12a are made different. was. On the other hand, as an alternative, the heights of the first fluorescent resin layer 11c and the second fluorescent resin layer 12c may be made different, and the emitted light colors of the first light emitting region 11a and the second light emitting region 12a may be made different.

Further, in the LED light emitting device 10, the first fluorescent resin layer 11c and the second fluorescent resin layer 12c were spot printed on the first LED die 11b and the second LED die 12b, respectively. On the other hand, for example, the first fluorescent resin layer 11c may be formed on the first LED die 11b by spot printing, and the second fluorescent resin layer 12c may seal the entire light emitting part 15a including the second LED die 12b. good. At this time, the transparent resin layer 16b becomes unnecessary. This makes manufacturing easier.

Further, the die bonding material 16a protruded from the bottom surface of the first LED die 11b and climbed up the side surfaces of the first LED die 11b and the second LED die 12b. This die-bonding material 16a blocks side-emitted light from the first LED die 11b and the second LED die 12b, and its surface functions as a reflective layer. In other words, the LED light emitting device 10 maintains high luminous efficiency while suppressing side emitted light with a simple structure without arranging additional light shielding members on the side surfaces of the first LED die 11b and the second LED die 12b. ing.

In addition, the die bonding material 16a that covers the surface of the mounting board 13 in the gap between the first LED die 11b and the second LED die 12b improves the reflection efficiency of the light emitting part 15a, regardless of whether the surface of the mounting board 13 is subjected to reflection treatment. I'm letting you do it.

(Second embodiment)
In the LED light emitting device 10 shown as the first embodiment, a first fluorescent resin is spot-printed on the upper part of the first LED die 11b included in the first light emitting area 11a and the second LED die 12b included in the second light emitting area 12a. A layer 11c and a second fluorescent resin layer 12c were formed. However, since spot printing is performed individually on the first LED die 11b and the second LED die 12b, the manufacturing load is large. As described above, the manufacturing load can be reduced by forming one dome-shaped fluorescent resin layer on the first LED die 11b (or the second LED die 12b) and forming another fluorescent resin layer with a different emission color using a filling method. . Furthermore, if the filling method can be applied to this one fluorescent resin layer, the manufacturing load can be further reduced. Therefore, as a second embodiment of the present invention, an LED light emitting device 20 in which the first fluorescent resin layer 11c and the second fluorescent resin layer 12c can be formed by a filling method will be described with reference to FIG. Note that since the LED light emitting device 20 has the same basic structure as the LED light emitting device 10, FIGS. 1 to 5 will be referred to for explanation, and common members in FIG. 10 will be denoted by common reference numerals.

FIG. 10 is a partial cross-sectional view of the LED light emitting device 20, showing main parts along line AA' in FIG. FIG. 10 shows two first light emitting regions 11a and two second light emitting regions 12a. Comparing FIG. 10 and FIG. 7, the LED light emitting device 20 is different from the LED light emitting device 10 in terms of the thickness of the second LED die 26b, the cross-sectional shapes of the first fluorescent resin layer 11c and the second fluorescent resin layer 12c, and the die bonding material 16a. The difference is the amount of creeping up and the absence of the transparent resin layer 16b.

As shown in FIG. 10, in the LED light emitting device 20, the first LED die 11b and the second LED die 26b have different thicknesses. That is, with the top surface of the mounting board 13 as a reference, the top surface of the first LED die 11b is higher than the top surface of the second LED die 26b. At this time, the second fluorescent resin layer 12c has a flat top surface except for the area occupied by the first LED die 11b, and the top surface has a height halfway between the top surface of the first LED die 11b and the top surface of the second LED die 26b. That is, the top surface of the second fluorescent resin 12c is lower than the top surface of the first LED die 11b and higher than the top surface of the second LED die 26b. Further, the first fluorescent resin layer 11c integrally and continuously covers the first LED die 11b and the second fluorescent resin layer 12c.

The first light emitting region 11a includes a first LED die 11b and a first fluorescent resin layer 11c, and the color of the light emitted from the first light emitting region 11a is 5000K due to the color mixing of the light emitted from the first LED die 11b and the first fluorescent resin layer 11c. It will be about. Similarly, the second light emitting region 12a includes a second LED die 26b and a second fluorescent resin layer 12c, and the emitted light color of the second light emitting region 12a is determined by the light emitted from the second LED die 26b and the second fluorescent resin layer 12c. The color will be mixed to about 3000K. Note that in the second light emitting region 12a, the first fluorescent resin layer 11c is also excited by the light emitted from the second LED die 26b, so if the light emission color is the same as that of the second light emitting region 12a included in the LED light emitting device 10, the LED It is necessary to adjust the component composition, thickness, etc. of the second fluorescent resin layer 12c of the light emitting device 20.

The LED light emitting device 20 is manufactured by changing the order of the first fluorescent resin coating step 36 and the second fluorescent resin coating step 37 shown in FIG. 8 and applying the filling method to each. That is, after the dam forming step 35 is completed, the second fluorescent resin is filled into the light emitting part 15a with a dispenser to form the second fluorescent resin layer 12c (second fluorescent resin coating step 37), and then the light emitting part 15a is filled with the dispenser. 15a is filled with a first fluorescent resin to form a first fluorescent resin layer 11c (first fluorescent resin coating step 36).

As described above, the LED light emitting device 20 is manufactured because spot printing is not applied in forming the first fluorescent resin layer 11c and the second fluorescent resin layer 12c (also because the transparent resin layer 16b is not required). becomes easier.

Note that in the LED light emitting device 20, the second LED die 26b is made thinner, and the heights of the upper surface of the first LED die 11b and the upper surface of the second LED die 26b are made different. However, making the heights of the top surface of the first LED die 11b and the top surface of the second LED die 26b different is not limited to this method. For example, when the first LED die 11b and the second LED die 12b (see FIG. 7) have the same thickness, a base may be formed on the upper surface of the mounting board 13 using silver paste or the like, and the first LED die 11b may be mounted there. .

(Third embodiment)
In the LED light emitting devices 10 and 20 shown as the first embodiment and the second embodiment, the first LED die 11b and the second LED die 12b and 26b were included in the first light emitting region 11a and the second light emitting region 12a, respectively. However, in the LED light emitting device of the present invention, in order to obtain high color mixing properties, it is sufficient that the first light emitting region 11a and the second light emitting region 12a are arranged close to each other in a planar manner; 11a and the second light emitting region 12a do not need to include the first LED die and the second LED die, respectively. Therefore, as a third embodiment of the present invention, an LED light emitting device 30 that does not include the second LED die 32b in the second light emitting region 12a will be described with reference to FIG. Note that since the LED light emitting device 30 and the LED light emitting device 10 have a basic structure in common, FIGS. 1 to 5 will be referred to for explanation, and common members in FIG. 11 will be denoted by common reference numerals.

FIG. 11 is a partial cross-sectional view of the LED light emitting device 30, showing main parts along line AA' in FIG. FIG. 11 shows two first light emitting regions 11a and two second light emitting regions 12a. Comparing FIG. 11 and FIG. 7, the LED light emitting device 30 differs from the LED light emitting device 10 in that the second LED die 32b is arranged below the first LED die 31b, and the planar size of the first LED die 31b is the same as that of the second LED die 31b. The difference is that the planar size is smaller than the die 32b, the transparent resin layer 16b is not present, and the cross-sectional shapes of the first fluorescent resin layer 11c, the second fluorescent resin layer 12c, the die bonding material 16a, and the wiring electrode 14b are different.

As shown in FIG. 11, in the LED light emitting device 30, the second LED die 32b is arranged below the first LED die 31b. At this time, the second LED die 32b is mounted face-down on the mounting board 13, and the first LED die 31b is mounted face-up on the second LED die 32b. When viewed in plan, the first LED die 31b is smaller than the second LED die 32b. The upper surface of the second LED die 32b is covered with a die bonding material 16a, and is further covered with a dome-shaped first fluorescent resin layer 11c together with the first LED die 31b via the die bonding material 16a. The second fluorescent resin layer 12c integrally and continuously seals the second LED die 32b, the first fluorescent resin layer 11c, and the wiring electrode 14b.

The first light-emitting region 11a includes a first LED die 31b and a first fluorescent resin layer 11c, and the color of the light emitted from the first light-emitting region 11a is 5000K due to the color mixing of the light emitted from the first LED die 31b and the first fluorescent resin layer 11c. It will be about. In contrast, the second light emitting region 12a includes the second fluorescent resin layer 12c, but does not include the second LED die 32b. That is, the second LED die 32b only excites the second fluorescent resin layer 12c included in the second light emitting region 12a. Therefore, the color of the light emitted from the second light emitting region 12a is obtained by converting the wavelength of the blue light emitted from the side surface of the second LED die 32b. In other words, the second light emitting region 12a alone does not produce white light. Therefore, the LED light emitting device 30 lights up the first LED die 31b together with the second LED die 32b and obtains blue light from the first light emitting region 11a, thereby obtaining desired white light with a low color temperature.

The method for manufacturing the LED light emitting device 30 matches the flowchart of the method for manufacturing the LED light emitting device 10 shown in FIG. 8 (there is no transparent resin coating step 38), but the content of each step is different. That is, in the die bonding step 33, the die bonding material 16a is applied to the upper surface of the second LED die 32b, and the first LED die 31b is mounted thereon. In the first fluorescent resin coating step 36, the first fluorescent resin is spot-printed on the upper surface of the second LED die 32b so as to cover the entire first LED die 31b in a dome shape, thereby forming the first fluorescent resin layer 11c. In the second fluorescent resin coating step 37, the light emitting portion 15a is filled with the second fluorescent resin using a dispenser to form the second fluorescent resin layer 12c.

Since the LED light emitting device 30 covers the entire side surface of the first LED die 31b with the first fluorescent resin layer 11c, the light emitting efficiency in the first light emitting region 11a can be increased compared to the LED light emitting device 10.

(Fourth embodiment)
In the LED light emitting device 30 shown as the third embodiment, the first light emitting region 11a emits white light with a high color temperature, and the second light emitting region 12a emits light containing many long wavelength components. However, the first light emitting region 11a may emit white light with a low color temperature, and the second light emitting region may emit white light with a high color temperature. Therefore, as a fourth embodiment of the present invention, an LED light emitting device 40 in which the color temperature of the first light emitting region 11a is lower than the color temperature of the second light emitting region 12a will be described with reference to FIG. Note that, like the LED light emitting device 30, the LED light emitting device 40 has the same basic structure as the LED light emitting device 10, so for explanation, FIGS. 1 to 5 will be referred to, and the common members in FIG. Use a common code.

FIG. 12 is a partial cross-sectional view of the LED light emitting device 40, with main parts drawn along line AA' in FIG. FIG. 12 shows two first light emitting regions 11a and two second light emitting regions 12a. Comparing FIG. 12 and FIG. 11, it can be seen that the LED light emitting device 40 is different from the LED light emitting device 30 in that it is equipped with a reflective member 43 and that the component compositions of the first fluorescent resin layer 41c and the second fluorescent resin layer 42c are different from each other. different.

As shown in FIG. 12, the LED light emitting device 40 includes a reflective member 43 having a triangular cross section between one second LED die 32b and another second LED die 32b. Further, the composition of the first fluorescent resin layer 41c is the same as that of the second fluorescent resin layer 12c included in the LED light emitting device 10. Similarly, the composition of the second fluorescent resin layer 42c is the same as that of the first fluorescent resin layer 11c included in the LED light emitting device 10.

The first light emitting region 11a includes a first LED die 31b and a first fluorescent layer 41c, and the color of the light emitted from the first light emitting region 11a is approximately 3000K due to the color mixture of the light emitted from the first LED die 31b and the first fluorescent resin layer 41c. become. On the other hand, the second light emitting region 12a includes the second fluorescent resin layer 42c, but does not include the second LED die 32b. When the second LED die 32b lights up, a portion of the blue light emitted from the side surface of the second LED die 32b is changed upward in the figure by the reflecting member 43, and becomes a blue light component in the second light emitting region 12a. , the remainder is wavelength-converted by the second fluorescent resin layer 42c and emitted to the outside from the second light emitting region 12a. As a result, the emitted light color of the second light emitting region 12a becomes approximately 5000K.

The method for manufacturing the LED light emitting device 40 is almost the same as the method for manufacturing the LED light emitting device 30, and only the preparation step 31 (see FIG. 8) is partially different from the preparation step 31 for the LED light emitting device 30 shown in FIG. . That is, in the LED light emitting device 40, the mounting board 13 to which the reflective member 43 is attached is prepared in the preparation step 31. Further, the LED light emitting device 40 may use a filler instead of the reflective member 43 to direct the traveling direction of the blue light upward in the figure.

10, 20, 30, 40...LED light emitting device,
11a...first light emitting region,
11b, 31b...first LED die,
11c, 41c...first fluorescent resin layer,
11d...first LED row,
11e...first circuit,
12a... second light emitting region,
12b, 26b, 32b...second LED die,
12c, 42c... second fluorescent resin layer,
12d...Second LED row,
12e...second circuit,
13... Mounting board,
14a...wire,
14b, 18a1, 18b1, 19a1, 19a2, 19b1... wiring electrode,
15...dam,
15a...light emitting part,
16a...Die bond material,
16b...transparent resin layer,
17a, 17b...Zener diode,
18a, 18b, 19a, 19b...power supply electrodes,
21a, 21b...anode,
22a, 22b... cathode,
23a, 23b...P layer,
24a, 24b...N layer,
31...preparation process,
32...Face-down mounting process,
33...Die bonding process,
34...Wire bonding process,
35...Dam formation process,
36...first fluorescent resin coating step,
37...Second fluorescent resin coating step,
38...Transparent resin coating step,
43... Reflective member.

Claims (9)

A mounting board,
An LED light emitting device comprising: a light emitting section in which a plurality of first light emitting regions that emit light in a first color and a plurality of second light emitting regions that emit light in a second color are arranged in a checkered pattern ;
The first light emitting region includes a first LED die mounted on the mounting board and a first fluorescent resin layer covering an upper surface of the first LED die,
The second light emitting region includes a second LED die mounted on the mounting board and a second fluorescent resin layer covering an upper surface of the second LED die ,
the first fluorescent resin layer and the second fluorescent resin layer are excited by a first LED die and a second LED die, respectively;
The LED light emitting device, wherein the first LED die is mounted face-up on the mounting board, and the second LED die is mounted face-down on the mounting board. A mounting board,
An LED light emitting device comprising: a light emitting section in which a plurality of first light emitting regions that emit light in a first color and a plurality of second light emitting regions that emit light in a second color are arranged in a checkerboard pattern;
The first light emitting region includes a first LED die and a second LED die mounted on the mounting substrate in a vertically stacked manner, and a first fluorescent resin layer covering the upper surface of the first LED,
The second light emitting region includes a second fluorescent resin layer covering a side surface of the second LED die,
the first fluorescent resin layer and the second fluorescent resin layer are excited by a first LED die and a second LED die, respectively;
The LED light emitting device, wherein the first LED die is mounted face-up on the second LED die, and the second LED die is mounted face-down on the mounting substrate. 3. The LED light emitting device according to claim 1, wherein the outer edge of the combined area of the first light emitting area and the second light emitting area is octagonal. 3. The LED light emitting device according to claim 1, wherein the first LED die is individually covered with the first fluorescent resin layer having a dome shape. 2. The LED light emitting device according to claim 1 , wherein the second LED die is individually covered with the second fluorescent resin layer having a dome shape. A die bonding material connecting the first LED die and the mounting board,
The LED light emitting device according to claim 1 , wherein the die bonding material covers the surface of the mounting board in a gap between the first LED die and the second LED die. Based on the top surface of the mounting board,
a top surface of the first LED die is higher than a top surface of the second LED die;
The LED light emitting device according to claim 1 , wherein the top surface of the second fluorescent resin layer is lower than the top surface of the first LED die and higher than the top surface of the second LED die. 3. The LED light emitting device according to claim 2 , wherein the first LED die has a planar size smaller than the planar size of the second LED die. 3. The LED light emitting device according to claim 2, wherein the second light emitting region includes a reflective member having a triangular cross section.