JP6822451B2 - Manufacturing method of light emitting device and light emitting device - Google Patents

Description

The present invention relates to a method for manufacturing a light emitting device and a light emitting device.

A light emitting device in which a plurality of semiconductor laser elements are mounted and connected in series is known (see, for example, FIG. 4 of Patent Document 1).

Special table 2016-518726

In the drive inspection of the semiconductor laser element included in such a light emitting device, each semiconductor laser element is inspected before the semiconductor laser element is mounted, or a plurality of semiconductors connected in series after the semiconductor laser element is mounted. The laser elements will be inspected together. However, in the former case, it is not possible to obtain a result that reflects the mounting state of the semiconductor laser element, and in the latter case, it is difficult to accurately detect minute changes in each semiconductor laser element.

In the method for manufacturing a light emitting device according to an embodiment of the present invention, a substrate having a first wiring, a second wiring, and a third wiring is electrically connected to the first wiring and the second wiring on the upper surface side of the substrate. The first semiconductor laser element and the second semiconductor laser element electrically connected to the second wiring and the third wiring are provided on the upper surface side of the substrate, and the first semiconductor laser element and the second semiconductor are provided. A step of preparing a light emitting device in which semiconductor laser elements are connected in series, and an electric current of the first semiconductor laser element is passed through the first wiring and the second wiring to electrically perform the first semiconductor laser element. A characteristic including at least one of a characteristic and an optical characteristic is measured, and a current is passed through the second wiring and the third wiring to the second semiconductor laser element to measure the characteristic of the second semiconductor laser element. A first measurement step, a step of passing a current through the first semiconductor laser element and the second semiconductor laser element for a certain period of time or longer, and a current flowing through the first wiring and the second wiring to the first semiconductor laser element. To measure the characteristics of the first semiconductor laser element, and pass a current through the second wiring and the third wiring to the second semiconductor laser element to flow the characteristics of the second semiconductor laser element. The second measurement step for measuring the current, the characteristics of the first semiconductor laser device obtained in the first measurement step, the characteristics of the first semiconductor laser device obtained in the second measurement step, and the first measurement step. Based on the characteristics of the second semiconductor laser element obtained in the above and the characteristics of the second semiconductor laser element obtained in the second measurement step, a step of evaluating each of the first semiconductor laser element and the second semiconductor laser element. , Are provided in this order.

The light emitting device according to one embodiment of the present invention has a substrate having a first wiring, a second wiring, and a third wiring, and a first wire electrically connected to the first wiring and the second wiring on the upper surface side of the substrate. In a space formed by combining the 1 semiconductor laser element, the second semiconductor laser element electrically connected to the second wiring and the third wiring on the upper surface side of the substrate, and the substrate, the first A lid fixed to the substrate is provided so that the semiconductor laser element and the second semiconductor laser element are arranged, and the first semiconductor laser element and the second semiconductor laser element are connected in series. A part of the first wiring, a part of the second wiring, and a part of the third wiring are exposed on the upper surface of the substrate outside the space formed by the substrate and the lid. doing.

According to the above manufacturing method, the characteristics of each semiconductor laser device can be confirmed, so that a highly reliable light emitting device can be obtained. Further, according to the above-mentioned light emitting device, a highly reliable light emitting device can be obtained.

FIG. 1 is a perspective view of a light emitting device according to the first embodiment. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. FIG. 3 is a perspective view for explaining the light emitting device according to the first embodiment. FIG. 4 is an enlarged view within the frame of the dotted line in FIG. FIG. 5 is a top view for explaining the light emitting device according to the first embodiment. FIG. 6 is an enlarged view within the frame of the dotted line in FIG. FIG. 7 is a perspective view for explaining the light emitting device according to the first embodiment. FIG. 8 is a flowchart showing a method of manufacturing the light emitting device according to the first embodiment.

A mode for carrying out the present invention will be described below with reference to the drawings. However, the forms shown below are for embodying the technical idea of the present invention and do not limit the present invention. The size and positional relationship of the members shown in each drawing may be exaggerated to clarify the explanation.

<First Embodiment>
FIG. 1 shows a perspective view of the light emitting device 200C according to the first embodiment, and FIG. 2 shows a cross-sectional view taken along the line II-II of FIG. Further, FIG. 3 shows a perspective view of the light emitting device 200A (light source 200A) excluding the lid 30 and the cover 100 in the light emitting device 200C, and FIG. 4 shows an enlarged view within the frame of the dotted line in FIG. Further, FIG. 5 shows a top view of the light emitting device 200A, and FIG. 6 shows an enlarged view within the frame of the dotted line in FIG. Further, FIG. 7 shows a perspective view of a light emitting device 200B (light source 200B with a lid) in which the lid 30 is fixed to the light emitting device 200A. In the present specification, for convenience, a device in which a semiconductor laser device 20 (hereinafter referred to as “LD element”) is fixed to a substrate 10 is referred to as a “light emitting device”. That is, the light source 200A in which the LD element 20 is fixed, the light source 200B with a lid in which the lid 30 is fixed to the light source 200A, and the light emitting device 200C in which the cover 100 is fixed to the light source 200B with a lid are called "light emitting devices". Therefore, they are collectively referred to as "light emitting device 200".

The method of manufacturing the light emitting device 200 is that the base 10 having the first wiring 11a, the second wiring 11b, and the third wiring 11c is electrically connected to the first wiring 11a and the second wiring 11b on the upper surface side of the base 10. The first LD element 20a and the second LD element 20b electrically connected to the second wiring 11b and the third wiring 11c are provided on the upper surface side of the substrate 10, and the first LD element 20a and the second LD element 20b are connected in series. A characteristic including at least one of the electrical characteristics and the optical characteristics of the first LD element 20a by passing a current through the first wiring 11a and the second wiring 11b to the first LD element 20a and the step of preparing the light emitting device. Hereinafter, the characteristic including at least one of the electrical characteristic and the optical characteristic is referred to as "characteristic X"), and a current is passed through the second wiring 11b and the third wiring 11c to the second LD element 20b to pass the second LD. A first measurement step of measuring the characteristic X of the element 20b, a step of passing a current for a certain period of time or more to the first LD element 20a and the second LD element 20b, and a first LD element 20a via the first wiring 11a and the second wiring 11b. A current is passed through the second LD element 20a to measure the characteristic X of the first LD element 20a, and a current is passed through the second LD element 20b via the second wiring 11b and the third wiring 11c to measure the characteristic X of the second LD element 20b. 2 The characteristics X of the first LD element 20a obtained in the first measurement step, the characteristics X of the first LD element 20a obtained in the second measurement step, and the characteristics X of the second LD element 20b obtained in the first measurement step. A step of evaluating each of the first LD element 20a and the second LD element 20b based on the characteristic X of the second LD element 20b obtained in the X and the second measurement step is provided in this order.

According to the above manufacturing method, the characteristics of the first LD element 20a and the second LD element 20b in a state of being used as a light emitting device (a state in which each LD element 20 is mounted on the substrate 10) can be inspected, respectively, and thus reliability. It is possible to obtain a high light emitting device. This point will be described below.

In a light emitting device including two or more LD elements, two or more LD elements may be connected in series because a current can be uniformly passed through each LD element. In such a light emitting device, when trying to inspect the characteristics of each LD element, each LD element is inspected before each LD element is mounted, or two or more are connected in series after each LD element is mounted. The LD elements will be inspected together. However, in the former case, deterioration of the characteristics of the LD element due to improper mounting of the LD element cannot be detected, and in the latter case, it is possible to detect a device whose characteristics are clearly changed. It is not possible to detect minute changes in each LD element. A specific example of the latter case will be described below. When inspecting whether there is a coating defect of the bonding material located between the LD element and the substrate, continue to apply a higher current than in actual use for a relatively long time, and observe the change over time before and after that. The test (time change test) is effective. However, heat is insufficiently drawn from one of the LD elements connected in series, and the forward voltage (hereinafter referred to as "Vf") is lower after the time-dependent change test than before the time-dependent change test. However, if the heat drawn from the other LD element is sufficient and the Vf is high after the time change test compared to before the time change test, defects can be detected by collectively inspecting the LD elements connected in series. It may disappear.

Therefore, in the present embodiment, in the light emitting device 200 in which two or more LD elements 20 are connected in series, the first wiring 11a, the second wiring 11b, and the third wiring 11c are used before and after the time-dependent change test. The characteristics X of the first LD element 20a and the second LD element 20b are individually inspected. As a result, each LD element 20 can be individually inspected to confirm the characteristics of each LD element, so that a highly reliable light emitting device can be obtained. The light emitting device used for a vehicle lamp or the like is required to have little change in characteristics for a long time. Therefore, the light emitting device according to the present embodiment is particularly suitable for use in a vehicle lamp or the like.

Hereinafter, a method of manufacturing the light emitting device 200 will be described with reference to the process flow of FIG.

(Process to prepare light emitting device)
First, the light emitting device 200 is prepared. Here, first, the light emitting device 200A shown in FIGS. 3 to 6 is prepared. The light emitting device 200A is arranged on the upper surface of the first wiring 11a and the base 10 having the first wiring 11a, the second wiring 11b, and the third wiring 11c, and is electrically connected to the first wiring 11a and the second wiring 11b. The first LD element 20a and the second LD element 20b arranged on the upper surface of the second wiring 11b and electrically connected to the second wiring 11b and the third wiring 11c are provided. At this time, the first LD element 20a and the second LD element 20b are connected in series.

The substrate 10 includes at least three wires 11a to 11c, and here includes seven wires 11a to 11g. The substrate 10 has a laminated structure including a plurality of insulating layers. The first wiring 11a constitutes a part of the upper surface of the base 10 inside the first frame portion 12 and a part of the upper surface of the base 10 outside the first frame portion 12. At this time, the first wiring 11a inside the first frame portion 12 and the first wiring 11a outside the first frame portion 12 are electrically connected by the first wiring 11a provided inside the base 10. There is. The material constituting the insulating _{layer, AlN, Si 3 N 4,} SiC, ZrO 2, Al 2 O 3, sapphire, and examples of the material constituting the wiring 11, Cu, Au, and the like. The second and subsequent wirings 11 have the same configuration as the first wiring 11a.

The first wiring 11a is used both when measuring the characteristics of the first LD element 20a and when driving a plurality of LD elements 20 connected in series. That is, the first wiring 11a is a common wiring used in both the case where the first LD element 20a is driven individually and the case where the first LD element 20a is driven collectively with the other LD element 20. As a result, the number of wirings can be reduced, so that the structure of the substrate can be simplified. Here, the 7th wiring 11g is also a common wiring. Here, the first wiring 11a includes two wiring portions inside the first frame portion 12. At this time, the first submount 50a on which the first LD element 20a is mounted is arranged in one wiring portion, and the other wiring portion is directly connected to the first wiring 11a outside the first frame portion 12. There is. Then, the other wiring portion and the first submount 50a are connected by a wire 81. The first wiring 11a may be composed of one wiring portion like the second wiring 11b. Further, although the fourth wiring 11d includes three wiring portions inside the first frame portion 12, it may be composed of one wiring portion as in the first wiring.

The substrate 10 includes a first frame portion 12 arranged so as to surround two or more LD elements 20. The first frame portion 12 can be connected by welding or the like. When connecting by welding, it is preferable that the first frame portion 12 is made of a material containing Fe as a main component. In addition, examples of the first frame portion 12 include simple substances or alloys of Cu, Al, Fe, Au, and Ag.

The substrate 10 further includes a second frame portion 13 provided so as to surround the first frame portion 12. The second frame portion 13 can be connected by a brazing material or the like. Examples of the material constituting the second frame portion 13 include simple substances or alloys of Cu, Al, Fe, Au, and Ag.

Inside the first frame portion 12, two or more submounts 50 are arranged on the upper surface of the substrate 10, and the LD element 20 is placed on each of the submounts 50. Specifically, the first LD element 20a is arranged on the upper surface of the first wiring 11a via the first submount 50a, and the second LD element 20b is arranged on the upper surface of the second wiring 11b via the second submount 50b. Have been placed. Similarly, the third and subsequent LD elements 20 are also arranged in order on the third and subsequent submounts 50, and are arranged on the upper surface of the third and subsequent wirings 11. Here, each LD element 20 is fixed to each submount 50 via a conductive layer 60 such as Au-Sn. Each LD element 20 is connected in series by a wire (thin metal wire) 81.

The LD element 20 oscillates a laser beam as excitation light for exciting a phosphor contained in the fluorescence unit 111. The peak wavelength of the laser beam emitted by the LD element 20 is preferably in the range of 320 nm to 530 nm, more preferably in the range of 430 nm to 480 nm. Examples of such an LD element 20 include those using a nitride semiconductor. As the LD element 20, it is preferable to use one whose characteristic X has been inspected before mounting on the substrate 10. As a result, the yield of the LD element 20 can be improved as compared with the case where the characteristic X is not inspected before being mounted on the substrate 10.

In the present embodiment, all the LD elements 20 arranged inside the first frame portion 12 are connected in series. As a result, the current flowing through each LD element 20 can be made constant, so that it becomes easy to reduce the variation in the emission intensity of each LD element 20. By connecting some LD elements 20 in series and connecting the remaining LD elements 20 in series, two or more LD element groups connected in series may be formed.

As the submount 50, it is preferable to use one having a coefficient of thermal expansion between the coefficient of thermal expansion of the substrate 10 and the coefficient of thermal expansion of the LD element 20. As a result, peeling of the LD element 20 and peeling of the submount 50 can be suppressed. When a material containing a nitride semiconductor is used as the LD element 20, for example, aluminum nitride or silicon carbide is used as the submount 50. Here, the second and subsequent submounts 50b to 50f have the same configuration as the first submount 50a, but may have different configurations.

The submount 50 is fixed to the substrate 10 by the following method. First, each of the first laser apparatus in which the first LD element 20a is mounted on the first submount 50a and the second laser apparatus in which the second LD element 20b is mounted on the second submount 50b is made of metal nanoparticles or metal. It is placed on the upper surface of the substrate 10 via a bonding material containing submicron particles and an organic solvent. At this time, the first laser device is mounted on the first wiring 11a, and the second laser device is mounted on the second wiring 11b. Next, by heating the bonding material, the first laser device and the second laser device are collectively bonded to the substrate 10. At this time, since it is difficult to uniformly pressurize all the laser devices due to the variation in height of each laser device and the like, the first laser device and the second laser device are joined to the substrate 10 without pressing. Since this method can fix a plurality of laser devices to the substrate 10 at once without applying excessive heat to the bonding material, it is suitable as a method for fixing a plurality of laser devices, but it is in a mounted state. Variations may occur. For example, if a gap is formed between the laser device and the substrate, the heat generated by the LD element 20 is less likely to be dissipated, so that the LD element 20 may be easily deteriorated. According to the manufacturing method of the present embodiment, since the inspection can be performed with the laser device mounted, the characteristics of each LD element 20 can be evaluated in consideration of the mounted state of the laser device, and the initial stage of the light emitting device can be evaluated. It becomes easier to detect defects.

The first submount 50a and the substrate 10 and the second submount 50b and the substrate 10 are bonded by metal nanoparticles or metal submicron particles. Here, they are joined by gold submicron particles. Here, the metal nanoparticles refer to metal particles having an average particle diameter of 1 nm to 100 nm, and the metal submicron particles refer to metal particles having an average particle diameter of 101 nm to 1 μm. For the average particle size, for example, using a projection photograph taken with a transmission electron microscope (TEM), the diameter equivalent to the projected area circle of 100 metal nanoparticles or metal submicron particles is randomly measured, and the average particle size is used. Can be calculated.

The submount 50 may be provided with a protective element 70 such as a Zener diode in order to prevent the LD element 20 from being destroyed. The protective element 70 is electrically connected to the LD element 20 by a wire.

The second wiring 11b and the second submount 50b are connected by a wire 82 (hereinafter, the wire used for series connection is referred to as "wire 81", and the other wires are referred to as "wire 82"). Thereby, by individually driving the first LD element 20a and the second LD element 20b, for example, the characteristic X of the first LD element 20a and the second LD element 20b can be measured individually.

The second submount 50b and the second wiring 11b are connected by a plurality of wires 82. The number of wires 81 is preferably larger than the number of wires 82, and the length of the wires 82 is preferably shorter than the length of the wires 81. For example, the length of one wire 82 is preferably shorter than the length of one wire 81. This is because the wire 82 is unlikely to be used in the actual driving of the light emitting device, and it is sufficient if a current can be passed in the first measurement step and the second measurement step. The same applies to the wire 82 connecting the third and subsequent submounts 50 and the third and subsequent wirings 11c to 11g.

The light reflecting portion 40 is arranged on the upper surface side of the substrate 10 via the wiring 11. The light reflecting unit 40 reflects the light from the LD element 20 upward. As the light reflecting portion 40, a mirror or the like in which at least a part of the surface is formed of a reflecting film such as a dielectric multilayer film can be used. As shown in FIGS. 3 and 4, one light reflecting unit 40 is provided for one LD element 20.

In the present embodiment, the first measurement step is performed in the state of the light emitting device 200B as shown in FIG. That is, by fixing the lid 30 to the substrate 10, a light emitting device 200B is prepared in which the space in which the first LD element 20a and the second LD element 20b are arranged (hereinafter referred to as "space S") is an airtight space. .. The light emitting device 200A before fixing the lid 30 may be prepared and the first measurement step may be performed. In the light emitting device 200B, a part of the first wiring 11a, a part of the second wiring 11b, and a part of the third wiring 11c are exposed on the upper surface of the substrate 10 outside the space S. The LD element 20 containing a nitride semiconductor tends to have a high energy density at the emission end face of the LD element 20, and dust such as organic substances tends to be collected on the emission end surface of the LD element 20. By making the space S an airtight space, it becomes easy to suppress dust collection on the emission end surface of the LD element 20.

The lid 30 includes a support portion 31, a first translucent portion 33 supported by the lower surface of the support portion 31, and an adhesive 32 for adhering the support portion 31 and the first translucent portion 33. The support portion 31 is connected to the first frame portion 12 by welding or the like. In the support portion 31, the portion through which the LD light passes penetrates. Then, the first translucent portion 33 is fixed so as to close the penetrating portion of the support portion 31. The material constituting the support portion 31 is preferably a material containing Fe as a main component. Examples of the support portion 31 include a simple substance or an alloy of Cu, Al, Fe, Au, and Ag. Examples of the material constituting the first translucent portion 33 include glass and sapphire. The thickness of the first translucent portion 33 can be, for example, 0.1 mm or more and 2 mm or less.

In the present embodiment, the space S is formed by the base 10, the first frame portion 12, and the lid 30, but the space is formed by the plate-shaped base and the lid 30 having a recessed portion below. S may be configured. That is, the lid may be arranged on the upper surface of the substrate so that the plurality of LD elements are arranged inside the recess.

(First measurement step)
Next, a current is passed through the first LD element 20a via the first wiring 11a and the second wiring 11b, the characteristic X of the first LD element 20a is measured, and the second LD is passed through the second wiring 11b and the third wiring 11c. A current is passed through the element 20b to measure the characteristic X of the second LD element 20b. Here, the first LD element 20a and the second LD element 20b measure the same characteristic X. In the first measurement step, a current higher than the current value when actually driving the light emitting device is passed for a relatively short time. Similarly, a current is passed through the third and subsequent LD elements 20c to 20f to measure the characteristic X.

A method of measuring the characteristic X of each LD element 20 will be described with reference to FIG. The characteristic X of the first LD element 20a is measured by passing a current through the first wiring 11a outside the first frame portion 12 and the second wiring 11b outside the first frame portion 12. At this time, the current from the first wiring 11a is applied to the wiring portion, the wire 81, the conductive layer 60 provided on the first submount 50a, the first LD element 20a, the wire 81, and the conductive layer provided on the second submount 50b. It flows through 60, the wire 82, and the second wiring 11b in this order. As a result, only the first LD element 20a emits light. In this step, for example, the current value is gradually increased from 0A to 4A in 4 seconds, and the characteristic X is measured all the time. Next, the characteristic X of the second LD element 20b is measured. The characteristic X of the second LD element 20b is measured by passing a current through the second wiring 11b and the third wiring 11c in the same manner. The same method is used for the third and subsequent LD elements 20.

The electrical characteristic is, for example, Vf, and the optical characteristic is, for example, at least one of the far field pattern (Far Field Pattern, hereinafter referred to as “FFP”), wavelength, and output of the LD element 20. In this step, it is preferable to measure at least Vf, and it is more preferable to measure at least Vf and FFP. The characteristics of each LD element 20 cannot be confirmed when a plurality of LD elements connected in series are collectively emitted and measured, but the characteristics of each LD element 20 can be confirmed by individually measuring as in the present embodiment. Therefore, it becomes easy to evaluate each LD element.

In the first measurement step, it is preferable to use the light emitting device 200B in consideration of dust collection on the LD element 20 and the like. When the light emitting device 200A is used in the first measurement step, the lid is fixed to the substrate between the first measurement step and the step of passing a current for a certain period of time or more to form the light emitting device 200B.

(Process of passing current for a certain period of time)
Next, a current is passed through each LD element 20 for a certain period of time or longer. Here, a current larger than the threshold current for a predetermined time is passed through all the LD elements 20 mounted on the substrate 10. As described above, by passing a high current to some extent for a certain period of time or more, it becomes easy to inspect the change with time of the LD element 20 in a relatively short time. The time for passing the current can be changed depending on the value of the flowing current. For example, it is preferably 1 hour or more and 20 hours or less, and more preferably 5 hours or more and 15 hours or less. By passing a time current equal to or greater than the above-mentioned lower limit value, it becomes easier to detect an initial failure of the LD element, and by passing a time current equal to or less than the above-mentioned upper limit value, deterioration of the LD element can be reduced. For example, a pulse current of 14 A is passed for about 9.5 hours while the temperature of the space where the light emitting device is arranged is set to 20 ° C.

Here, a current is passed in series with the first LD element 20a and the second LD element 20b. That is, the wire 81 is used to pass a current through all the LD elements 20. As a result, the current can be passed through the plurality of LD elements 20 at once, so that it is possible to confirm the change with time of all the LD elements 20 in a shorter time than when the current is passed through each of the LD elements 20. Can be done. In this step, the wire 82 connected to the submount 50 and the wiring 11 can be used to individually apply a current to each LD element 20.

(Second measurement step)
Next, the characteristic X of each LD element 20 is measured in the same manner as in the first measurement. Specifically, a current is passed through the first wiring 11a and the second wiring 11b to the first LD element 20a, the characteristic X of the first LD element 20a is measured, and the characteristic X is measured via the second wiring 11b and the third wiring 11c. A current is passed through the second LD element 20b, and the characteristic X of the second LD element 20b is measured.

(Process for evaluating semiconductor laser devices)
Next, each of the LD elements 20 is evaluated based on the characteristic X obtained in the first measurement and the characteristic X obtained in the second measurement. Specifically, the characteristic X of the first LD element 20a obtained in the first measurement step, the characteristic X of the first LD element 20a obtained in the second measurement step, and the characteristic X of the second LD element 20b obtained in the first measurement step. Each LD element 20 is evaluated based on X and the characteristic X of the second LD element 20b obtained in the second measurement step.

For example, when the LD element 20 and the wiring 11 have a poor connection, the Vf obtained in the second measurement step is lower than the Vf obtained in the first measurement step. It is considered that this is caused because the heat generated by the LD element 20 is less likely to be dissipated to the substrate 10 due to the poor bonding, and the LD element 20 tends to become hot. When actually driven in this state, the current increases, the amount of heat generated by the LD element 20 further increases, and the deterioration of the LD element 20 becomes faster. Therefore, if the Vf obtained in the second measurement is excessively low, it is determined to be defective. For example, when Vf is 3.6 or less or 4.1 or more, it is determined to be defective. Further, when the nitride semiconductor is used as the LD element 20, if the space S is not sufficiently airtightly sealed, dust is collected in the LD element 20 in the step of passing a current for a certain period of time or more, so that the first measurement can be performed. The FFP obtained and the FFP obtained in the second measurement may be different. For example, the peak of FFP obtained in the second measurement deviates from the peak of FFP obtained in the first measurement. When the output is being measured, for example, if the output is 2.2 W or less or 2.75 W or more, it is determined to be defective. Further, when the wavelength is being measured, if the desired peak wavelength of the LD element 20 is 450 nm, it is determined to be defective if it is 445 nm or less or 455 nm or more. In these cases, the optical characteristics may change when the light emitting device is actually driven, so it is determined to be defective.
In the present embodiment, the characteristic X is measured in each of the first measurement step and the second measurement step. However, if the reference value of the characteristic X for comparison with the measured value of the characteristic X in the second measurement step, which is used for determining the defect of the LD element 20, is known in advance, the first measurement step is not performed. May be good. That is, the defect of the LD element 20 can be determined by comparing the reference value of the characteristic X with the measured value of the characteristic X in the second measurement step.
Further, when the reference value of the characteristic X for comparison with the measured value of the characteristic X in the first measurement step, which is used for determining the defect of the LD element 20, is known in advance, the step of passing electricity for a certain period of time or longer. And the second measurement step does not have to be performed. That is, if the characteristic X in the first measurement step can be evaluated without confirming the change with time, it is not necessary to perform the step of passing electricity for a certain period of time or longer and the second measurement step. In this case, the defect of the LD element 20 can be determined by comparing the reference value of the characteristic X with the measured value of the characteristic X in the first measurement step.

Here, it is classified into a plurality of ranks according to the variation in the obtained characteristics. As a result, the characteristics of the LD element 20 can be made uniform. For example, the Vf of the LD element 20 is ranked and classified in advance. Then, it is determined that the light emitting device provided with the LD element 20 having a rank other than the specific rank is defective. It should be noted that only good or bad may be judged without ranking.

(Step of fixing the second translucent portion 90 and the cover 100)
Next, a second translucent portion 90 is provided on the upper surface of the lid 30 so as to close the penetrating portion of the support portion 31 on the upper side. The second translucent unit 90 has a function as a lens, and refracts the laser light from each LD element 20 so that the laser light from each LD element 20 irradiates the lower surface of the fluorescent unit 111. Examples of the material constituting the second translucent portion 90 include optical glass such as BK7 and a transparent resin. The thickness of the second translucent portion 90 can be, for example, 1 mm or more and 5 mm or less.

Next, the cover 100 provided with the opening is fixed to the upper surface of the second frame portion 13. The cover 100 is provided with an optical component 110 so as to close the opening of the cover 100. A second light-shielding portion 120 is provided between the side surface of the optical component 110 and the cover 100 so as to block the light from the optical component 110. The cover 100 has a side portion that extends downward. As a result, the volume that contributes to heat dissipation increases, so that the heat generated by the optical component 110 can be efficiently dissipated.

The optical component 110 is provided on the fluorescent unit 111, the first light-shielding unit 112 provided on the side surface of the fluorescent unit 111, the dielectric multilayer film 113 provided on the lower surface of the fluorescent unit 111, and the lower surface of the dielectric multilayer film 113. The heat conductive portion 114 provided and the antireflection filter 115 provided on the lower surface of the heat conductive portion 114 are provided. By arranging the heat conductive portion 114 directly under the fluorescent portion 111 via the dielectric multilayer film 113 that reflects fluorescence, it is possible to easily take out the fluorescence while dissipating the heat generated in the fluorescent portion 111. The fluorescent unit 111 includes a phosphor, and for example, one containing at least one of a YAG phosphor, a LAG phosphor, and a Ca-α sialone phosphor can be used. As the first light-shielding portion, light-shielding ceramics such as alumina can be used. As the heat conductive portion 114, for example, sapphire, SiC, or the like can be used.

In the top view, the second light-shielding portion 120 is arranged so as to surround the optical component 110. As shown in FIG. 2, the second light-shielding portion 120 is preferably provided so as to cover the entire side surface of the heat conductive portion 114. As a result, it is possible to prevent light from escaping laterally from the heat conductive portion 114. As the second light-shielding portion 120, for example, a resin to which light-scattering particles such as titanium oxide are added can be used.

In the present embodiment, since the optical characteristics are measured in the first measurement step and the second measurement step, the second translucent portion 90 and the cover 100 are fixed to the lid 30 and the substrate 10 after the second measurement step. There is. This makes it easy to accurately evaluate the characteristic X of each LD element 20. Further, by fixing the cover 100 or the like after the evaluation, it is possible to prevent the members such as the cover 100 from being wasted. When only the electrical characteristics are measured in the first measurement step and the second measurement step, this step may be performed before the first measurement step. That is, the light emitting device 200C may be prepared in the step of preparing the light emitting device, and the first measurement step may be performed.

After the second measurement step, the wire 82 may be broken by passing a certain current or more through the wire 82. When a current flows in series, an external terminal is connected to the first wiring, but if the external terminal is connected to the first wiring and the second wiring due to misalignment of the external terminal, etc., it is evenly distributed to the first LD element and the second LD element. Since no current flows through the LD elements, it may be difficult for all LD elements connected in series to emit light evenly. On the other hand, by breaking the wire 82, even if the external terminal is unintentionally connected to the second wiring, the current does not flow through the second LD element, so that the current can easily flow uniformly. For example, when a wire 82 made of Au and having a diameter of 60 μm is used, the wire 82 can be broken by passing a current of about 7.8 A through one wire 82.

The light emitting device according to the embodiment can be used for a vehicle lamp or the like.

10 ... Base 11 ... Wiring 12 ... 1st frame 13 ... 2nd frame 20 ... Semiconductor laser element 30 ... Lid 31 ... Support 32 ... Adhesive 33 ... 1st translucent part 40 ... Light reflecting part 50 ... Sub Mount 60 ... Conductive layer 70 ... Protective element 81, 82 ... Wire 90 ... Second translucent part 100 ... Cover 110 ... Optical component 111 ... Fluorescent part 112 ... First light-shielding part 113 ... Dielectric multilayer film 114 ... Heat conductive part 115 ... Anti-reflection filter 120 ... Second shading unit 200, 200A, 200B, 200C ... Light emitting device

Claims (11)

A substrate having the first wiring, the second wiring, and the third wiring, a first semiconductor laser element electrically connected to the first wiring and the second wiring on the upper surface side of the substrate, and an upper surface side of the substrate. A second semiconductor laser element electrically connected to the second wiring and the third wiring, and a second submount arranged between the second semiconductor laser element and the second wiring. The first semiconductor laser element and the second semiconductor laser element are electrically connected to the conductive layer provided on the second submount, and the second wiring and the conductive layer are connected by a wire. The step of preparing a light emitting device in which the first semiconductor laser element and the second semiconductor laser element are connected in series, and
A current is passed through the first semiconductor laser element via the first wiring and the second wiring to measure the characteristics including at least one of the electrical characteristics and the optical characteristics of the first semiconductor laser element, and the second. A first measurement step of measuring the characteristics of the second semiconductor laser element by passing a current through the wiring and the third wiring to the second semiconductor laser element.
A step of passing a current over a certain period of time through the first semiconductor laser element and the second semiconductor laser element, and
A current is passed through the first semiconductor laser element via the first wiring and the second wiring to measure the characteristics of the first semiconductor laser element, and the second wiring and the third wiring are used to measure the characteristics. A second measurement step in which a current is passed through the second semiconductor laser element to measure the characteristics of the second semiconductor laser element, and
The characteristics of the first semiconductor laser device obtained in the first measurement step, the characteristics of the first semiconductor laser device obtained in the second measurement step, and the second semiconductor laser device obtained in the first measurement step. A step of evaluating each of the first semiconductor laser element and the second semiconductor laser element based on the characteristics and the characteristics of the second semiconductor laser element obtained in the second measurement step is provided in this order.
The first semiconductor laser device and the second semiconductor laser device each include a nitride semiconductor.
By fixing the lid to the substrate between the step of preparing the light emitting device and the step of the first measurement, the first semiconductor laser element , the second semiconductor laser element , the second submount, and the above. The space in which the conductive layer and the wire are arranged is defined as an airtight space .
A part of the first wiring, a part of the second wiring, and a part of the third wiring are exposed on the upper surface of the substrate outside the space formed by the substrate and the lid. a method of manufacturing a light emitting device wherein the lid is characterized Rukoto fixed to the base body. A substrate having the first wiring, the second wiring, and the third wiring, a first semiconductor laser element electrically connected to the first wiring and the second wiring on the upper surface side of the substrate, and an upper surface side of the substrate. A second semiconductor laser element electrically connected to the second wiring and the third wiring, and a second submount arranged between the second semiconductor laser element and the second wiring. The first semiconductor laser element and the second semiconductor laser element are electrically connected to the conductive layer provided on the second submount, and the second wiring and the conductive layer are connected by a wire. The step of preparing a light emitting device in which the first semiconductor laser element and the second semiconductor laser element are connected in series, and
A current is passed through the first semiconductor laser element via the first wiring and the second wiring to measure the characteristics including at least one of the electrical characteristics and the optical characteristics of the first semiconductor laser element, and the second. A first measurement step of measuring the characteristics of the second semiconductor laser element by passing a current through the wiring and the third wiring to the second semiconductor laser element.
The first semiconductor laser device and the second semiconductor laser device are based on the characteristics of the first semiconductor laser device obtained in the first measurement step and the characteristics of the second semiconductor laser device obtained in the first measurement step. The process of evaluating each is prepared in this order,
The first semiconductor laser device and the second semiconductor laser device each include a nitride semiconductor.
By fixing the lid to the substrate between the step of preparing the light emitting device and the step of the first measurement, the first semiconductor laser element , the second semiconductor laser element , the second submount, and the above. The space in which the conductive layer and the wire are arranged is defined as an airtight space.
A part of the first wiring, a part of the second wiring, and a part of the third wiring are exposed on the upper surface of the substrate outside the space formed by the substrate and the lid. a method of manufacturing a light emitting device wherein the lid is characterized Rukoto fixed to the base body. The method for manufacturing a light emitting device according to claim 1 or 2, wherein in the first measurement step, a forward voltage is measured as the electrical characteristic. The method for manufacturing a light emitting device according to any one of claims 1 to 3, wherein in the first measurement step, a farfield pattern is measured as the optical characteristic. In the step of passing a current for a certain period of time or longer, the first semiconductor laser device and the second
The method for manufacturing a light emitting device according to claim 1 or claim 3 or 4, wherein a current is passed through the semiconductor laser device in series. In the process of preparing the light emitting device,
The first laser device in which the first semiconductor laser device is mounted on the first submount and the second laser device in which the second semiconductor laser device is mounted on the second submount are each formed of metal nanoparticles or metal nanoparticles. It is placed on the upper surface of the substrate via a bonding material containing metal submicron particles and an organic solvent.
By heating the bonding material without pressing the first laser device and the second laser device, the first laser device and the second laser device are collectively bonded to the substrate. The method for manufacturing a light emitting device according to any one of claims 1 to 5. Any one of claims 1 or 3 to 6, which cites claim 1, further comprising a step of breaking the wire by passing a certain or more current through the wire after the second measurement step. The method for manufacturing a light emitting device according to a section. A substrate having the first wiring, the second wiring, and the third wiring,
A first semiconductor laser device electrically connected to the first wiring and the second wiring on the upper surface side of the substrate, and electrically connected to the second wiring and the third wiring on the upper surface side of the substrate. 2nd semiconductor laser element and
It further has a second submount arranged between the second semiconductor laser device and the second wiring.
The second wiring and the conductive layer provided on the second submount are connected by a wire.
The first semiconductor laser element and the second semiconductor laser element are electrically connected to the conductive layer.
The first semiconductor laser element , the second semiconductor laser element , the second submount, the conductive layer, and the wire are fixed to the substrate so as to be arranged in the space formed in combination with the substrate. With a lid and
The first semiconductor laser element and the second semiconductor laser element are connected in series.
A part of the first wiring, a part of the second wiring, and a part of the third wiring are exposed on the upper surface of the substrate outside the space formed by the substrate and the lid. A light emitting device characterized by being present. A substrate having the first wiring, the second wiring, and the third wiring,
A first semiconductor laser device electrically connected to the first wiring and the third wiring on the upper surface side of the substrate, and electrically connected to the first wiring and the third wiring on the upper surface side of the substrate. 2nd semiconductor laser element and
It further has a second submount arranged between the second semiconductor laser device and the second wiring.
A wire extending from the second wiring toward the second submount and being broken in the middle,
The first semiconductor laser element and the second semiconductor laser element are electrically connected to the conductive layer provided on the second submount.
The first semiconductor laser element , the second semiconductor laser element , the second submount, the conductive layer, and the wire are fixed to the substrate so as to be arranged in the space formed in combination with the substrate. With a lid and
The first semiconductor laser element and the second semiconductor laser element are connected in series.
A part of the first wiring, a part of the second wiring, and a part of the third wiring are exposed on the upper surface of the substrate outside the space formed by the substrate and the lid. A light emitting device characterized by being present. The first semiconductor laser device and the second semiconductor laser device each include a nitride semiconductor.
The light emitting device according to claim 8 or 9, wherein the space formed by the substrate and the lid is an airtight space. The first semiconductor laser element is arranged on the upper surface side of the substrate via the first submount, and the first submount and the substrate, and the second submount and the substrate are metal nanoparticles or the substrate, respectively. The light emitting device according to any one of claims 8 to 10, wherein the light emitting device is bonded by metal submicron particles.

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