Light emitting device and method for manufacturing light emitting device

Abstract

To provide a light-emitting device in which variation and inclination of a mounting position of a flip-chip semiconductor light-emitting element are suppressed, and to provide a method of manufacturing a semiconductor light-emitting element capable of achieving high mounting accuracy by suppressing variation and inclination of a mounting position of a flip-chip semiconductor light-emitting element.SOLUTION: A substrate including a high-voltage side wiring and a low-voltage side wiring on a surface thereof, a flip-chip type semiconductor light-emitting element including a high-voltage side electrode and a low-voltage side electrode respectively connected to the high-voltage side wiring and the low-voltage side wiring via a conductive adhesive, and a first resin formed body provided between the high-voltage side wiring and the low-voltage side wiring and between a surface of the substrate and a lower surface of the semiconductor light-emitting element, the first resin forming body being in contact with the high-voltage-side wire and the low-voltage-side wire or the conductive adhesive provided on each of the high-voltage-side wire and the low-voltage-side wire, and being provided in a region of the semiconductor light-emitting element in plan view.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a light emitting device and a method for manufacturing a light emitting device. [Background technology]

[0002] Semiconductor light emitting devices equipped with flip-chip type semiconductor light emitting elements are used as light sources for headlamps and lighting fixtures. When semiconductor light emitting devices are used in combination with lenses, high precision is required in the position of the light emitting area and the light radiation characteristics. These precisions are affected by the mounting position precision and horizontality of the flip-chip type semiconductor light emitting element, so high mounting precision of the flip-chip type semiconductor light emitting element is required. Generally, to achieve high mounting precision, stud bumps are used to mount flip-chip type semiconductor light emitting elements using balls such as Au. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-218398 Summary of the Invention [Problem to be solved by the invention]

[0004] On the other hand, with reflow soldering using solder paste, it is difficult to achieve the above-mentioned high mounting accuracy due to variations in the amount of solder and the influence of paste printing accuracy.In Patent Document 1, underfill resin 7 made of a resin different from the sealing resin that seals the flip-chip type semiconductor light-emitting element is filled into the gaps that form between the electrodes of the flip-chip type semiconductor light-emitting element and the substrate.

[0005] However, the underfill 7 in Patent Document 1 is filled after the flip-chip type semiconductor light-emitting element is mounted (see

[0023] ), so it does not have the effect of improving the mounting accuracy of the light-emitting element. Furthermore, semiconductor light-emitting elements generally have two electrodes, and when mounting a semiconductor light-emitting element on a copper wiring substrate, there is a problem that the solder does not wet and spread well, making the chip prone to tilting.

[0006] Furthermore, when adhesive is applied to the semiconductor light-emitting element to fix it before soldering, the adhesive is allowed to overflow outside the semiconductor light-emitting element so that it can be seen, which can result in problems such as a reduction in the light output of the light-emitting device or changes in chromaticity.

[0007] The present disclosure has been made to solve the above problems, and aims to provide a light-emitting device in which variations and tilts in the mounting position of flip-chip type semiconductor light-emitting elements are suppressed, and a method for manufacturing semiconductor light-emitting elements that can suppress variations and tilts in the mounting position of flip-chip type semiconductor light-emitting elements and achieve high mounting accuracy. [Means for solving the problem]

[0008] The present disclosure has been made to achieve the above-mentioned object, and provides a light emitting device comprising: a substrate having high-voltage side wiring and low-voltage side wiring on its surface; a flip-chip type semiconductor light emitting element having a high-voltage side electrode and a low-voltage side electrode connected to the high-voltage side wiring and the low-voltage side wiring, respectively, via a conductive adhesive; and a first resin formation body provided between the high-voltage side wiring and the low-voltage side wiring and between the surface of the substrate and the underside of the semiconductor light emitting element, the first resin formation body being in contact with the conductive adhesive provided on the high-voltage side wiring and the low-voltage side wiring or the high-voltage side wiring and the low-voltage side wiring, respectively, and being provided within the area of ​​the semiconductor light emitting element when viewed in a plan view.

[0009] According to such a light emitting device, variations in the mounting position and tilt of the flip-chip type semiconductor light emitting element are suppressed.

[0010] In this case, the first resin formation body may be an epoxy resin.

[0011] This makes it possible to more stably suppress variations and tilts in the mounting positions of the semiconductor light emitting elements.

[0012] In this case, the light emitting device can include a second resin formation body that seals the semiconductor light emitting element, the second resin formation body covering the upper surface of the semiconductor light emitting element, and the second resin formation body intercalating between the conductive adhesive that connects the high-voltage side wiring and the high-voltage side electrode and the conductive adhesive that connects the low-voltage side wiring and the low-voltage side electrode.

[0013] This makes it possible to reduce peeling and displacement of the second resin formation body.

[0014] In this case, the second resin formed body may be a silicon-based resin.

[0015] This makes it possible to more stably reduce peeling and displacement of the second resin formation body.

[0016] In this case, the first resin formation body can be a light-emitting device that, when viewed in a plan view, has a shape that is long in the direction in which the gap that electrically separates the high-voltage side wiring and the low-voltage side wiring extends, and short in the direction from the high-voltage side wiring to the low-voltage side wiring.

[0017] This makes it possible to more stably suppress variations and tilts in the mounting positions of the semiconductor light emitting elements.

[0018] The present disclosure also provides a method for manufacturing a light emitting device including a flip-chip type semiconductor light emitting element, the method including the steps of: providing a conductive adhesive on each of the high-voltage side wiring and the low-voltage side wiring provided on the surface of a substrate; providing a first resin formation body between the high-voltage side wiring and the low-voltage side wiring; placing the semiconductor light emitting element on the first resin formation body while aligning the high-voltage side electrode of the semiconductor light emitting element with the conductive adhesive on the high-voltage side wiring, and the low-voltage side electrode of the semiconductor light emitting element with the conductive adhesive on the low-voltage side wiring; hardening the first resin formation body; and performing a heat treatment after the step of hardening the first resin formation body to bond the high-voltage side electrode and the high-voltage side wiring, and the low-voltage side electrode and the low-voltage side wiring, respectively, via the conductive adhesive.

[0019] According to this method for manufacturing a light emitting device, it is possible to suppress variations in the mounting position and tilt of the flip-chip type semiconductor light emitting element, thereby achieving high mounting accuracy.

[0020] In this case, the method for manufacturing a light emitting device may use a conductive adhesive containing flux.

[0021] Such materials can be suitably used.

[0022] In this case, the method for manufacturing a light emitting device may be such that, in the step of providing the first resin form body, the first resin form body is provided inside an area intended to mount the semiconductor light emitting element.

[0023] This makes it possible to more stably suppress variations and tilts in the mounting position of the flip-chip type semiconductor light emitting element, thereby achieving high mounting accuracy.

[0024] In this case, the method for manufacturing a light emitting device may be such that, in the step of providing the conductive adhesive, the conductive adhesive is provided at four corners of the region intended to mount the semiconductor light emitting element, spaced apart from each other.

[0025] This makes it possible to more stably suppress variations and tilts in the mounting position of the flip-chip type semiconductor light emitting element, thereby achieving high mounting accuracy.

[0026] At this time, a substrate on which a resist is arranged on the high-voltage side wiring and the low-voltage side wiring outside a region where the semiconductor light-emitting element is to be mounted is used as the substrate, In the process of applying the conductive adhesive, the method for manufacturing a light-emitting device may be such that the conductive adhesive is applied to both the high-voltage side wiring and the low-voltage side wiring so that the conductive adhesive extends onto the resist.

[0027] This makes it possible to easily ensure the thickness of the conductive adhesive.

[0028] In this case, in the process of providing the first resin formation body, the method for manufacturing a light emitting device can be such that, when viewed in a plane, the first resin formation body is long in the direction in which the gap that electrically separates the high-voltage side wiring and the low-voltage side wiring extends, and short in the direction from the high-voltage side wiring to the low-voltage side wiring.

[0029] This makes it possible to more stably suppress variations in the mounting position and tilt of the semiconductor light emitting element.

[0030] At this time, the method further includes a resin sealing step of sealing the semiconductor light emitting element with a second resin formation body, The second resin body is made of a material softer than the first resin body, This method for manufacturing a light emitting device can include forming the second resin formation body so as to cover the upper surface of the semiconductor light emitting element and to extend into the area outside the first resin formation body between the conductive adhesive connecting the high-voltage side wiring and the high-voltage side electrode and the conductive adhesive connecting the low-voltage side wiring and the low-voltage side electrode.

[0031] This makes it possible to form a second resin formation body that is less susceptible to peeling and misalignment.

[0032] In this case, the method for manufacturing a light emitting device can use a silicone resin as the second resin formation body.

[0033] This makes it possible to more stably reduce peeling and displacement of the second resin formation body.

[0034] In this case, the method for manufacturing a light emitting device can use an epoxy resin as the first resin formation body.

[0035] This makes it possible to more stably suppress variations in the mounting position and tilt of the semiconductor light emitting element. [Effects of the Invention]

[0036] As described above, the light emitting device of the present disclosure reduces variations and tilts in the mounting position of the flip-chip type semiconductor light emitting element. The manufacturing method of the light emitting device of the present disclosure reduces variations and tilts in the mounting position of the flip-chip type semiconductor light emitting element, thereby achieving high mounting accuracy. [Brief explanation of the drawings]

[0037] [Figure 1] 1 is a diagram illustrating a light-emitting device according to the present disclosure. [Figure 2] 1 is a diagram illustrating a method for manufacturing a light-emitting device according to the present disclosure. [Figure 3] 10 is a diagram showing an example of an arrangement of a conductive adhesive and a first resin formation body before heat treatment in a method for manufacturing a light emitting device according to the present disclosure. [Figure 4] 1 is a diagram illustrating an embodiment of a method for manufacturing a light emitting device according to the present disclosure, up to the stage of mounting a semiconductor light emitting element. DETAILED DESCRIPTION OF THE INVENTION

[0038] The present disclosure will be described in detail below, but the present disclosure is not limited thereto.

[0039] As described above, there has been a demand for a light emitting device in which variations and tilts in the mounting position of a flip-chip type semiconductor light emitting element are suppressed, and a method for manufacturing a semiconductor light emitting element that can suppress variations and tilts in the mounting position of a flip-chip type semiconductor light emitting element and achieve high mounting accuracy.

[0040] As a result of extensive research into the above-mentioned problems, the inventors have found that a light-emitting device comprising a substrate having high-voltage side wiring and low-voltage side wiring on its surface, a flip-chip type semiconductor light-emitting element having a high-voltage side electrode and a low-voltage side electrode connected to the high-voltage side wiring and the low-voltage side wiring, respectively, via a conductive adhesive, and a first resin formation body provided between the high-voltage side wiring and the low-voltage side wiring and between the surface of the substrate and the underside of the semiconductor light-emitting element, the first resin formation body being in contact with the conductive adhesive provided on the high-voltage side wiring and the low-voltage side wiring or the high-voltage side wiring and the low-voltage side wiring, respectively, and being provided within the area of ​​the semiconductor light-emitting element in a planar view, can suppress variation and tilt in the mounting position of the flip-chip type semiconductor light-emitting element, and have completed the present disclosure.

[0041] The present inventor has also discovered that a method for manufacturing a light emitting device including a flip-chip type semiconductor light emitting element, the method including the steps of: providing a conductive adhesive on each of the high-voltage side wiring and the low-voltage side wiring provided on the surface of a substrate; providing a first resin formation body between the high-voltage side wiring and the low-voltage side wiring; placing the semiconductor light emitting element on the first resin formation body while aligning the high-voltage side electrode of the semiconductor light emitting element with the conductive adhesive on the high-voltage side wiring, and the low-voltage side electrode of the semiconductor light emitting element with the conductive adhesive on the low-voltage side wiring; hardening the first resin formation body; and performing a heat treatment after the step of hardening the first resin formation body to bond the high-voltage side electrode and the high-voltage side wiring, and the low-voltage side electrode and the low-voltage side wiring, respectively, via the conductive adhesive, makes it possible to suppress variation and tilt in the mounting position of the flip-chip type semiconductor light emitting element and achieve high mounting accuracy, and has completed the present disclosure.

[0042] The following description will be made with reference to the drawings.

[0043] [Light-emitting device] First, the light-emitting device of the present disclosure will be described. FIG. 1(A) is a cross-sectional view of the light-emitting device of the present disclosure, and FIG. 1(B) shows the positional relationship of each component when viewed from above. FIG. 1(A) is a cross-sectional view corresponding to the X-X' position in FIG. 1(B). As shown in FIG. 1(A), the light-emitting device 10 of the present disclosure includes a substrate 1 having high-voltage side wiring 2A and low-voltage side wiring 2B on its surface, and a flip-chip type semiconductor light-emitting element 7 having high-voltage side electrodes 6A and low-voltage side electrodes 6B connected to the high-voltage side wiring 2A and low-voltage side wiring 2B, respectively, via a conductive adhesive 4. In addition, a first resin formation body 5 is provided between the high-voltage side wiring 2A and the low-voltage side wiring 2B, and between the surface of the substrate 1 and the underside of the semiconductor light-emitting element 7. The first resin formation body 5 is in contact with the high-voltage side wiring 2A and the low-voltage side wiring 2B, or in contact with the conductive adhesive 4 provided on each of the high-voltage side wiring 2A and the low-voltage side wiring 2B. Furthermore, the first resin formation body 5 is provided within the area of ​​the semiconductor light emitting element 7 in a plan view. In other words, the first resin formation body 5 does not protrude from the semiconductor light emitting element 7, and therefore, when viewed from above, the first resin formation body 5 is hidden by the semiconductor light emitting element 7 and is not visible (FIG. 1(B)). Note that in FIG. 1(B), the high-voltage side wiring 2A and the conductive adhesive 4, and the low-voltage side wiring 2B and the conductive adhesive 4, are substantially overlapping, but they do not necessarily have to be completely overlapping.

[0044] In such a light-emitting device of the present disclosure, by interposing the first resin forming body 5 between the surface of the substrate 1 and the underside of the semiconductor light-emitting element 7, the influence of variations in the amount of conductive adhesive 4 such as solder and paste printing accuracy is small, and there is little variation or tilt in the mounting position of the flip-chip type semiconductor light-emitting element 7, thereby achieving high mounting accuracy.

[0045] In addition, the first resin formation body 5 allows the height of the conductive adhesive 4 to be optimized, thereby improving the heat dissipation properties of the conductive adhesive 4. Furthermore, contact between the conductive adhesive 4 and the first resin formation body 5 prevents deformation of the conductive adhesive 4 due to thermal expansion, thereby mitigating distortion stress caused by temperature changes inside the conductive adhesive 4 and improving the reliability of the light emitting device. Furthermore, poor light emission characteristics and light extraction loss caused by the conductive adhesive 4 creeping up to the side surfaces of the semiconductor light emitting element 7 can be reduced. Furthermore, suppressing the tilt of the semiconductor light emitting element 7 also provides other effects such as improved light distribution characteristics and easier image recognition and image inspection.

[0046] (substrate) The substrate 1 is not particularly limited as long as it has high-voltage wiring 2A and low-voltage wiring 2B on its surface. Examples include ceramic substrates such as alumina or AlN, and resin-based substrates such as glass epoxy substrates, each having high-voltage wiring 2A and low-voltage wiring 2B on its surface. Generally, semiconductor light-emitting elements have two electrodes, and there are two wirings on the substrate corresponding to the electrodes of the semiconductor light-emitting element. However, the present disclosure can also be applied to semiconductor light-emitting elements with three electrodes that incorporate a protection diode for protection against electrostatic surges, and the light-emitting device of the present disclosure is not limited to this.

[0047] The high-voltage side wiring 2A and the low-voltage side wiring 2B are connected to the high-voltage side electrode 6A and the low-voltage side electrode 6B of the semiconductor light-emitting element 7 via the conductive adhesive 4. The high-voltage side wiring 2A and the low-voltage side wiring 2B may be, for example, a part or all of a Cu wiring pattern provided on a substrate. It is also preferable to flux the surface of the Cu to increase wettability. This is because when the conductive adhesive 4 arranged on the outside of the high-voltage side electrode 6A and the low-voltage side electrode 6B is heat-treated, the effect of drawing the conductive adhesive 4 toward the inside of the high-voltage side electrode 6A and the low-voltage side electrode 6B is more effective. Furthermore, the high-voltage side wiring 2A and the low-voltage side wiring 2B may be formed in the shape of a substantially rectangular island.

[0048] 1, 2(A), etc., it is preferable to use, as the substrate 1, a substrate in which a resist 3 is arranged on the high-voltage side wiring 2A and the low-voltage side wiring 2B outside the intended mounting area for the semiconductor light emitting element 7. This is because, when the conductive adhesive 4 arranged on the outside of the high-voltage side electrode 6A and the low-voltage side electrode 6B is heat-treated, the conductive adhesive 4 is more effectively drawn into the inside of the high-voltage side electrode 6A and the low-voltage side electrode 6B.

[0049] (semiconductor light emitting element) The semiconductor light-emitting element 7 is a flip-chip type light-emitting element that has a high-voltage electrode 6A and a low-voltage electrode 6B on one main surface and emits light from the other main surface, so long as other structures and light-emitting characteristics are not particularly limited. Known LED chips that emit light ranging from ultraviolet to blue can be selected and used, or an LED chip that emits red light can also be used. For example, a blue light-emitting diode including a nitride semiconductor (GaN)-based light-emitting layer can be used.

[0050] (First resin formed body) The light emitting device of the present disclosure comprises a first resin forming body 5 provided between the high-voltage side wiring 2A and the low-voltage side wiring 2B, and between the surface of the substrate 1 and the underside of the semiconductor light emitting element 7, which is in contact with the conductive adhesive 4 provided on the high-voltage side wiring 2A and the low-voltage side wiring 2B, or on each of the high-voltage side wiring 2A and the low-voltage side wiring 2B, and is provided within the area of ​​the semiconductor light emitting element 7 when viewed in a plan view.

[0051] There are no particular limitations on the material of the first resin formation body 5, and a thermosetting or photosetting material can be used. The material of the first resin formation body 5 is preferably an epoxy resin, as this can more stably suppress variations and tilts in the mounting position of the semiconductor light emitting element.

[0052] 3, the first resin formation body 5 preferably has a shape (e.g., elliptical) that is long in the direction (direction a) of the gap 9 that electrically separates the high-voltage side wiring 2A and the low-voltage side wiring 2B, and short in the direction (direction b) toward the high-voltage side wiring 2A and the low-voltage side wiring 2B, in plan view. This shape can more stably suppress variations in the mounting position and tilt of the semiconductor light-emitting element. Furthermore, since the first resin formation body 5 is provided between the multiple electrodes 6A, 6B and the connecting metal (conductive adhesive 4), contact with the electrodes 6A, 6B due to moisture contamination is reduced, and migration occurring between the electrodes 6A, 6B is reduced.

[0053] As shown in FIGS. 1 and 2 , the first resin formation body 5 is positioned inside the semiconductor light-emitting element 7 so as not to protrude beyond the light-reflecting material in a plan view. When a semiconductor light-emitting element 7 is used in which a reflective film is provided closer to the electrodes 6A and 6B than the light-emitting layer, light emitted from the light-emitting layer is reflected by the reflective film and not absorbed by the first resin formation body 5. Typically, flip-chip semiconductor light-emitting elements 7 have a light-reflecting structure on their undersides, so almost no light is emitted downward from the flip-chip semiconductor light-emitting element 7. Therefore, even if the first resin formation body 5 does not contain a light-reflecting material such as a filler, the mounting accuracy of the flip-chip semiconductor light-emitting element 7 can be improved without being affected by the light reflectance of the first resin formation body 5. However, the first resin formation body 5 may contain a reflective filler. Furthermore, because the first resin formation body 5 contacts and fixes the semiconductor light-emitting element 7 to the conductive adhesive 4, stress applied to the conductive adhesive 4 can be reduced, ensuring high reliability. By making the thickness of the first resin formation body 5, for example, 30 μm or more, the thickness of the conductive adhesive 4 can be ensured, and high heat dissipation properties can be obtained. Furthermore, when the conductive adhesive 4 arranged on the outside of the high-voltage electrode 6A and the low-voltage electrode 6B is heat-treated, the conductive adhesive 4 is more effectively drawn into the high-voltage electrode 6A and the low-voltage electrode 6B. The thickness of the first resin formation body 5 is more preferably 50 μm to 80 μm.

[0054] (Conductive adhesive) The conductive adhesive 4 connects and fixes the high-voltage wiring 2A on the surface of the substrate 1 to the high-voltage electrode 6A of the semiconductor light-emitting element 7, and connects and fixes the low-voltage wiring 2B on the surface of the substrate 1 to the low-voltage electrode 6B of the semiconductor light-emitting element 7. Such conductive adhesive 4 is not particularly limited as long as it can connect the wiring and the electrodes. For example, solder (solder paste) can be used. In particular, Sn-containing solder such as SAC305 is preferred.

[0055] (Second resin formed body) The light-emitting device of the present disclosure may include a second resin formation body 8 that encapsulates the semiconductor light-emitting element 7. In this case, the second resin formation body 8 covers the upper surface of the semiconductor light-emitting element 7 and may also be embedded on the lower surface of the semiconductor light-emitting element 7 between the conductive adhesive 4 connecting the high-voltage wiring 2A and the high-voltage electrode 6A and the conductive adhesive 4 connecting the low-voltage wiring 2B and the low-voltage electrode 6B. When an encapsulating resin is used to encapsulate the semiconductor light-emitting element 7, peeling of the encapsulating resin can be a problem due to heat generated by the chip. However, by embedding a portion of the second resin formation body 8 between the semiconductor light-emitting element 7 and the substrate 1 as in the present disclosure, peeling and displacement of the second resin formation body 8 can be reduced. In this case, it is more preferable that the second resin formation body 8 and the first resin formation body 5 are in contact with each other. If a first resin formation body 5 different from the second resin formation body 8 is in contact with the gap between multiple electrodes (high-voltage side electrode 6A, low-voltage side electrode 6B) and the conductive adhesive 4, the second resin formation body 8 is less likely to peel off, contact with the electrodes due to moisture contamination is reduced, and electrode migration can be reduced.

[0056] The material for the second resin formation body 8 is not particularly limited, but a silicone-based resin is preferred. Such a material can more stably reduce peeling and misalignment of the second resin formation body, making it a preferred material for sealing and filling. The second resin formation body 8 may also contain a reflective filler or a wavelength conversion substance. For example, a two-layer structure is preferred, in which the lower portion of the second resin formation body 8 in contact with the lower and lateral surfaces of the semiconductor light emitting element 7 contains a relatively large amount of reflective filler, and the upper portion of the second resin formation body 8 in contact with the upper surface of the semiconductor light emitting element 7 contains a relatively large amount of wavelength conversion substance. This further reduces the amount of light reaching the first resin formation body 5, thereby further increasing the luminous efficiency.

[0057] [Lighting equipment] According to the present disclosure, it is possible to provide a lighting device including the semiconductor light emitting device described above. The lighting device is not particularly limited, and examples thereof include general lighting, street lighting, and headlamps.

[0058] [Method of manufacturing a light-emitting device] A method for manufacturing a light-emitting device according to the present disclosure that includes a flip-chip type semiconductor light-emitting element will be described with reference to Figures 2, 3, and 4. Details of each component, etc., that were mentioned in the description of the light-emitting device above may be omitted. Furthermore, the description of each component in the method for manufacturing a light-emitting device below can also be applied to each component of the light-emitting device described above.

[0059] (Process of applying conductive adhesive) First, using the substrate 1 shown in FIG. 2(A), conductive adhesive 4a is provided on each of the high-voltage wiring 2A and the low-voltage wiring 2B provided on the surface of the substrate 1 as shown in FIG. 2(B). The thickness of the conductive adhesive 4a is, for example, 80 nm to 120 nm. A typical light-emitting element has two electrodes, and there are also two wirings on the substrate corresponding to the electrodes of the light-emitting element. Here, as shown in FIG. 3, conductive adhesive 4a such as solder paste is preferably provided at four locations on both ends of the longitudinal direction (direction a) of each wiring (high-voltage wiring 2A, low-voltage wiring 2B), i.e., on the two wirings, including areas facing the four corners of the intended mounting area 7A for the semiconductor light-emitting element 7. This arrangement can more effectively prevent misalignment and tilting of the semiconductor light-emitting element 7 when it is mounted. Furthermore, it is preferable to provide conductive adhesives 4a at a distance from each other even on the same wiring. This arrangement can more effectively prevent voids from occurring in the conductive adhesive 4a after heat treatment. Furthermore, as shown in Figures 2 and 3, it is preferable to provide a resist 3 on areas of the substrate and wiring that are not connected by the conductive adhesive 4a, to prevent the formation of residues of the conductive adhesive, such as solder, after heat treatment.

[0060] 3, it is preferable to provide the conductive adhesive 4a so that it extends to the outside of the wiring (onto the resist 3) in a direction (direction a or b, or both directions a and b) away from the first resin formation body 5, including a portion of the wiring of the substrate that connects to each of the multiple electrodes of the flip-chip type semiconductor light emitting element 7. This makes it possible to provide a gap (described later) so that the first resin formation body 5 and the conductive adhesive 4a do not come into contact with each other, while ensuring the amount of conductive adhesive 4a.

[0061] Furthermore, to ensure that a gap is provided between the first resin formation body 5 and the conductive adhesive 4a to prevent contact with each other, it is preferable to chamfer the corner of each conductive adhesive 4a that faces the first resin formation body 5 more than the other corners of the conductive adhesive 4a when viewed from above, as shown in Fig. 3. This ensures a gap between the conductive adhesive 4a and the first resin formation body 5 even when the first resin formation body 5 is formed relatively wide to ensure its thickness, and even if the first resin formation body 5 is formed wider than desired due to variations in the amount of the first resin formation body 5. The order of the step of providing the conductive adhesive 4a and the step of providing the first resin formation body 5 described below may be reversed.

[0062] (Step of Providing First Resin Formation Body) As shown in FIGS. 2(C) and 3, a first resin formation body 5 is provided between the high-voltage wiring 2A and the low-voltage wiring 2B (gap 9 in FIG. 3). The thickness of the first resin formation body 5 is, for example, 120 to 180 nm. The first resin formation body 5 functions to stably bond a flip-chip type semiconductor light-emitting element 7 to the substrate 1. In this case, as shown in FIG. 3, the first resin formation body 5 that bonds the flip-chip type semiconductor light-emitting element 7 to the substrate 1 is preferably provided in the gap 9 of the wiring so as to be separated from the portion of the wiring where the conductive adhesive 4a is provided (or will be provided). Furthermore, as shown in FIGS. 2(C) and 3, the first resin formation body 5 is preferably provided inside a planned mounting area 7A for the flip-chip type semiconductor light-emitting element 7 when viewed from above.

[0063] Arranging the first resin formation body 5 and the conductive adhesive 4a so that they do not come into contact with each other prevents mixing of the flux components contained in the conductive adhesive (solder paste) with the components of the first resin formation body 5, thereby achieving a sufficient flux effect and reliably preventing poor conductivity (poor soldering, etc.). However, after the first resin formation body 5 is cured, even if the first resin formation body 5 and the conductive adhesive 4 come into contact with each other, migration of the components of the first resin formation body 5 to the conductive adhesive 4 is suppressed, so there is no particular problem even if the first resin formation body 5 and the conductive adhesive 4 come into contact with each other. The first resin formation body 5 in the light-emitting device according to the present disclosure comes into contact with the conductive adhesive 4 provided on the high-voltage side wiring 2A and the low-voltage side wiring 2B, or on the high-voltage side wiring 2A and the low-voltage side wiring 2B. It is actually preferable that the first resin formation body 5 and the conductive adhesive 4 come into contact with each other without any gaps therebetween.

[0064] The material of the first resin formation body 5 is not particularly limited, and may be a thermosetting, photocurable, or time-curable material. The first resin formation body 5 adheres the semiconductor light emitting element 7 to the substrate 1 when hardened, and also functions to fix the position of the semiconductor light emitting element 7 during the step of bonding via a conductive adhesive. It is preferable to select a material for the first resin formation body 5 that maintains sufficient connection strength within the temperature range of the step of bonding via a conductive adhesive (main heating). Furthermore, an epoxy-based resin can be used as the first resin formation body 5.

[0065] As described above, when arranging the first resin formation body 5, it is preferable to prevent contact with the conductive adhesive 4a, but after heat treatment is performed to bond the semiconductor light emitting element 7 with the conductive adhesive 4, the first resin formation body 5 may be in contact with the conductive adhesive 4. Therefore, to make it easier for the first resin formation body 5 and the conductive adhesive 4 to come into contact with each other, the first resin formation body 5 may be partially provided on the wiring (the high-voltage side wiring 2A and the low-voltage side wiring 2B) as shown in FIG.

[0066] In order to prevent the first resin formation body 5 from losing its shape and coming into contact with the conductive adhesive 4a when providing the first resin formation body 5, it is advisable to increase the viscosity and thixotropy of the first resin formation body 5 (the viscosity is preferably 50 Pa·sec or more, and the thixotropy is preferably 4 or more). The viscosity is a value measured using a rotational viscometer, and the thixotropy is a value calculated as the ratio of the viscosity when the rotational viscometer is rotated at 1 rpm to the viscosity when the rotational viscometer is rotated at 10 rpm.

[0067] 3, the first resin formation body 5 is preferably arranged (as viewed from above) so that, in plan view, it is long in the direction of the gap 9 that electrically separates the high-voltage side wiring 2A and the low-voltage side wiring 2B, and short in the direction from the high-voltage side wiring 2A to the low-voltage side wiring 2B. Specifically, it can be an ellipse or a substantially rectangle that is long in the direction parallel to the gap 9 of the wiring electrodes. Such a shape increases the adhesive strength between the flip-chip type semiconductor light emitting element 7 and the substrate 1, and also increases the connection area of ​​the first resin formation body 5.

[0068] The thickness of the first resin formation body 5 is preferably close to the total thickness of the wiring (high-voltage side wiring 2A and low-voltage side wiring 2B), conductive adhesive 4a, and electrodes (high-voltage side electrode 6A, low-voltage side electrode 6B), or slightly thicker than this total thickness. Furthermore, the first resin formation body 5 is preferably provided so as to include the center of the flip-chip type semiconductor light emitting element 7. This is because the flip-chip type semiconductor light emitting element 7 can be fixed more stably.

[0069] (Step of placing semiconductor light emitting element on first resin formation body) Next, as shown in FIG. 2(D), the semiconductor light emitting element 7 is placed on the first resin formation body 5 while aligning the conductive adhesive 4a on the high-voltage electrode 6A of the semiconductor light emitting element 7 and the high-voltage wiring 2A, and the conductive adhesive 4a on the low-voltage electrode 6B of the semiconductor light emitting element 7 and the low-voltage wiring 2B. It is preferable to place the semiconductor light emitting element 7 on the substrate 1 so that the first resin formation body 5 is located between the multiple electrodes of the semiconductor light emitting element 7, as this provides greater stability. In this way, the use of the first resin formation body 5 stably places the semiconductor light emitting element 7, thereby preventing the semiconductor light emitting element 7 from tilting. When the semiconductor light emitting element 7 is placed, the first resin formation body 5 is pressed and deformed, and the thickness of the first resin formation body 5 becomes, for example, 50 μm to 80 μm.

[0070] Fig. 4 shows another embodiment of the method for manufacturing a light emitting device according to the present disclosure up to the placement of semiconductor light emitting elements 7. Fig. 4 shows an example in which a substrate having multiple pairs of high-voltage side wiring 2A and low-voltage side wiring 2B provided thereon (Fig. 4(A)), a conductive adhesive is placed (Fig. 4(B)), a first resin formation body is placed (Fig. 4(C)), and multiple semiconductor light emitting elements 7 are placed (Fig. 4(D)).

[0071] (Step of curing the first resin formation body) Next, as shown in FIG. 2(E), the first resin formation body 5 is cured. This bonds the semiconductor light emitting element 7 to the substrate 1. The curing conditions for the first resin formation body 5 may be appropriately selected depending on the characteristics of the first resin formation body 5. When a thermosetting material is used for the first resin formation body 5, heat treatment may be performed under appropriate conditions. When a photocurable material is used for the first resin formation body 5, light irradiation treatment using UV light or the like may be performed under appropriate conditions. When a time-curable material is used for the first resin formation body 5, time curing treatment may be performed under appropriate conditions. Note that using a thermosetting material for the first resin formation body 5 allows the first resin formation body 5 to be cured as preheating prior to the heat treatment performed in the process of bonding the electrodes and wiring via the conductive adhesive, which will be described later. This is preferable from the standpoints of process simplification and improved throughput. In this case, it is preferable to select a material for the first resin formation body 5 that promotes a sufficient curing reaction during preheating.

[0072] In one example where a thermosetting material is used for first resin formation body 5, first resin formation body 5 can be hardened by placing the substrate in a reflow furnace and performing a preheating heat treatment (temperature of about 120°C to 190°C, time of about 60 seconds to 120 seconds). Note that the hardening treatment of first resin formation body 5 may be performed while pressing flip-chip type semiconductor light emitting element 7 from above.

[0073] When the first resin forming body 5 hardens, the thickness of the conductive adhesive 4 (solder) can be made relatively thick while reducing the possibility of the semiconductor light-emitting element 7 sinking or rotating (tilting) toward the substrate when the conductive adhesive 4a later melts, thereby improving the heat dissipation from the semiconductor light-emitting element 7 and the reliability of the conductive adhesive.

[0074] (Process of bonding using conductive adhesive) After the process of hardening the first resin formation body 5 described above, a heat treatment is performed to bond the high-voltage side electrode 6A and the high-voltage side wiring 2A, and the low-voltage side electrode 6B and the low-voltage side wiring 2B, respectively, via the conductive adhesive 4 (Figure 2(F)).

[0075] When a thermosetting material is used as the first resin forming body 5, the conductive adhesive 4a melts during the main heating following the pre-heating, bonding the wiring on the substrate (high-voltage side wiring 2A, low-voltage side wiring 2B) to the flip-chip type semiconductor light-emitting element 7, and connecting the wiring on the substrate to multiple electrodes (high-voltage side electrode 6A, low-voltage side electrode 6B) of the flip-chip type semiconductor light-emitting element 7.

[0076] Because the semiconductor light emitting element 7 typically has two electrodes, if the first resin formation body 5 is not used and two corresponding conductive adhesives 4a are used, self-alignment occurs in only one direction. As a result, the semiconductor light emitting element 7 is prone to tilting during reflow of the conductive adhesive 4a, such as solder. On the other hand, in an embodiment according to the present disclosure, the semiconductor light emitting element 7 is adhered and fixed by the hardened first resin formation body 5, which can prevent the chip from tilting.

[0077] 3, when the conductive adhesive 4a is placed in four locations (on both ends of the wiring), the molten conductive adhesive 4 connects to the four ends of the semiconductor light emitting element 7, thereby more stably suppressing tilt of the chip. Also, when resist is provided on a partial area of ​​the wiring (high-voltage side wiring 2A, low-voltage side wiring 2B) on the substrate, the conductive adhesive 4a on the resist migrates (is drawn) onto the exposed wiring by utilizing its wettability and cohesiveness, thereby contributing to ensuring the thickness of the conductive adhesive 4.

[0078] The molten conductive adhesive 4 has good wettability with the wiring on the substrate and good wettability with the electrodes of the flip-chip semiconductor light-emitting element 7. However, it has poor wettability with the resist and substrate material on the substrate and wiring. Taking advantage of this property, the wiring on the substrate and the electrodes of the flip-chip semiconductor light-emitting element 7 are arranged in the gaps between the conductive adhesive 4a on the same wiring, and the portions other than the electrodes of the flip-chip semiconductor light-emitting element 7 are made of the resist and substrate material of the substrate. By moving (pulling) the conductive adhesive 4a to the wiring areas on the substrate where it was not placed before heat treatment and the electrode areas of the flip-chip semiconductor light-emitting element 7, the conductive adhesive 4 can be combined as the conductive adhesive 4, as shown in Figure 1B. In this case, it is preferable to use a material with high fluidity when molten, such as Sn-containing solder such as SAC305, as the conductive adhesive 4.

[0079] Furthermore, since the first resin formation body 5 is provided between the electrodes (between the wirings) when the conductive adhesive 4 moves, bridging due to the conductive adhesive 4 between the electrodes is suppressed. Furthermore, since the gaps between the electrodes of the flip-chip type semiconductor light emitting element 7 and between the semiconductor light emitting element 7 and the substrate 1 are not hollow (air gaps) but are provided with the first resin formation body 5 before reflow, voids and flux residue in the conductive adhesive 4 are reduced when the conductive adhesive 4 moves, and migration can be further prevented. Furthermore, since the first resin formation body 5 has already hardened when heat treatment is performed in the step of bonding via the conductive adhesive, migration of components of the first resin formation body 5 to the conductive adhesive 4 is suppressed even when the first resin formation body 5 and the conductive adhesive 4 come into contact.

[0080] As described above, the first resin forming body 5 is hardened when the conductive adhesive 4a melts, so there is little variation in the amount of conductive adhesive 4 or the effect of paste printing accuracy, and high mounting accuracy can be achieved with little variation or tilt in the mounting position of the flip-chip type semiconductor light-emitting element 7.

[0081] Furthermore, since the height of the conductive adhesive 4 can be optimized, the heat dissipation properties of the conductive adhesive 4 and the reliability of the conductive adhesive 4 are improved. Also, it is possible to reduce poor light emission characteristics and light extraction loss caused by the conductive adhesive 4 creeping up onto the side surfaces of the semiconductor light emitting element 7. Furthermore, since the tilt of the semiconductor light emitting element 7 is suppressed, other effects can be achieved, such as improved light distribution characteristics and easier image recognition and image inspection.

[0082] (Resin sealing process) Furthermore, as shown in FIG. 2(G), it is also preferable to encapsulate the semiconductor light emitting element 7 with a second resin formation body 8. In this case, the second resin formation body 8 is preferably made of a material softer than the first resin formation body 5, and the second resin formation body 8 is preferably formed so as to cover the upper surface of the semiconductor light emitting element 7 and extend outside the first resin formation body 5 between the conductive adhesive 4 connecting the high-voltage wiring 2A and the high-voltage electrode 6A and the conductive adhesive 4 connecting the low-voltage wiring 2B and the low-voltage electrode 6B. This reduces peeling and misalignment of the second resin formation body 8. Furthermore, creeping of the second resin formation body 8 around the semiconductor light emitting element 7 can be suppressed. Furthermore, the uniformity of the second resin formation body 8 around the semiconductor light emitting element 7 is improved, resulting in improved light distribution characteristics. The second resin formation body 8 can also be formed from multiple layers, such as a layer containing a relatively large amount of reflective filler or a layer containing a relatively large amount of wavelength conversion material.

[0083] As described above, according to the present disclosure, it is possible to provide a light emitting device in which variation and tilt in the mounting position of a flip-chip type semiconductor light emitting element are suppressed, and to achieve high mounting accuracy by suppressing variation and tilt in the mounting position of a flip-chip type semiconductor light emitting element.

[0084] The present specification includes the following aspects. [1]: A substrate having high-voltage wiring and low-voltage wiring on its surface; a flip-chip type semiconductor light emitting element including a high-voltage side electrode and a low-voltage side electrode connected to the high-voltage side wiring and the low-voltage side wiring via a conductive adhesive, respectively; A light emitting device comprising: a first resin formation body provided between the high-voltage side wiring and the low-voltage side wiring, and between the surface of the substrate and the underside of the semiconductor light emitting element, the first resin formation body being in contact with the conductive adhesive provided on the high-voltage side wiring and the low-voltage side wiring or the high-voltage side wiring and the low-voltage side wiring, respectively, and being provided within the area of ​​the semiconductor light emitting element when viewed in a plane. [2]: The light emitting device according to [1], wherein the first resin formation body is an epoxy resin. [3]: The light emitting device of [1] or [2] above, further comprising a second resin forming body that seals the semiconductor light emitting element, the second resin forming body covering the upper surface of the semiconductor light emitting element and interposing between the conductive adhesive that connects the high voltage side wiring and the high voltage side electrode and the conductive adhesive that connects the low voltage side wiring and the low voltage side electrode. [4]: The light emitting device according to [3], wherein the second resin formed body is a silicone resin. [5]: The light-emitting device of [1], [2], [3] or [4], wherein the first resin formation body has a shape that, when viewed in a plan view, is long in the direction in which a gap that electrically separates the high-voltage side wiring and the low-voltage side wiring extends and is short in the direction from the high-voltage side wiring to the low-voltage side wiring. [6]: A method for manufacturing a light emitting device including a flip-chip type semiconductor light emitting element, a step of providing a conductive adhesive on each of the high-voltage side wiring and the low-voltage side wiring provided on the surface of the substrate; providing a first resin formation body between the high-voltage side wiring and the low-voltage side wiring; a step of placing the semiconductor light emitting element on the first resin formation body while aligning the high-voltage side electrode of the semiconductor light emitting element with the conductive adhesive on the high-voltage side wiring, and the low-voltage side electrode of the semiconductor light emitting element with the conductive adhesive on the low-voltage side wiring; curing the first resin formation; A method for manufacturing a light emitting device, comprising the steps of: performing a heat treatment after a step of hardening the first resin formation body, and bonding the high-voltage side electrode and the high-voltage side wiring, and the low-voltage side electrode and the low-voltage side wiring, respectively, via the conductive adhesive. [7]: The method for manufacturing a light emitting device according to [6], wherein the conductive adhesive contains a flux. [8]: The method for manufacturing a light emitting device according to [6] or [7] above, wherein in the step of providing the first resin form body, the first resin form body is provided inside a region where the semiconductor light emitting element is to be mounted. [9]: The method for manufacturing a light-emitting device according to [6], [7] or [8], wherein in the step of applying the conductive adhesive, the conductive adhesive is applied at a distance from each other at four corners of the area intended to mount the semiconductor light-emitting element.

[10] : A substrate in which a resist is arranged on the high-voltage side wiring and the low-voltage side wiring outside the region where the semiconductor light-emitting element is to be mounted is used as the substrate, The method for manufacturing a light-emitting device according to [6], [7], [8] or [9] above, wherein in the step of applying the conductive adhesive, the conductive adhesive is applied on each of the high-voltage side wiring and the low-voltage side wiring so that the conductive adhesive extends onto the resist.

[11] : A method for manufacturing a light emitting device according to [6], [7], [8], [9] or

[10] , wherein in the step of providing the first resin formation body, the first resin formation body is arranged so that, in a plan view, it has a shape that is long in the direction of extension of a gap that electrically separates the high-voltage side wiring and the low-voltage side wiring, and short in the direction from the high-voltage side wiring to the low-voltage side wiring.

[12] : The method further includes a resin sealing step of sealing the semiconductor light emitting element with a second resin formed body, The second resin body is made of a material softer than the first resin body, A method for manufacturing a light emitting device according to any one of [6], [7], [8], [9],

[10] , and

[11] above, wherein the second resin formation body is formed so as to cover the upper surface of the semiconductor light emitting element and extend outside the first resin formation body between the conductive adhesive connecting the high-voltage side wiring and the high-voltage side electrode and the conductive adhesive connecting the low-voltage side wiring and the low-voltage side electrode.

[13] : The method for manufacturing a light emitting device according to

[12] , wherein the second resin formed body is a silicone resin.

[14] : The method for manufacturing a light-emitting device according to [6], [7], [8], [9],

[10] ,

[11] or

[12] , wherein the first resin forming body is an epoxy resin.

[0085] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any configuration that is substantially identical to the technical idea described in the claims of the present disclosure and that provides similar effects is included within the technical scope of the present disclosure. [Explanation of symbols]

[0086] 1...substrate, 2A...high voltage side wiring, 2B...low voltage side wiring, 3...resist, 4, 4a...conductive adhesive, 5...first resin formed body, 6A...high voltage side electrode, 6B...low-voltage side electrode, 7...flip-chip type semiconductor light-emitting element, 7A...region for mounting semiconductor light emitting element; 8...second resin formed body; 9...Gap, 10...Light-emitting device.

Claims

1. a substrate having high-voltage wiring and low-voltage wiring on its surface; a flip-chip type semiconductor light emitting element including a high-voltage side electrode and a low-voltage side electrode connected to the high-voltage side wiring and the low-voltage side wiring via a conductive adhesive, respectively; A light-emitting device characterized by comprising: a first resin formation body provided between the high-voltage side wiring and the low-voltage side wiring, and between the surface of the substrate and the underside of the semiconductor light-emitting element, the first resin formation body being in contact with the conductive adhesive provided on the high-voltage side wiring and the low-voltage side wiring or the high-voltage side wiring and the low-voltage side wiring, respectively, and being provided within the area of ​​the semiconductor light-emitting element when viewed in a plane.

2. 2. The light emitting device according to claim 1, wherein the first resin formation body is an epoxy resin.

3. The light-emitting device described in claim 1, characterized in that it comprises a second resin formation body that seals the semiconductor light-emitting element, the second resin formation body covering the upper surface of the semiconductor light-emitting element and intercalating between the conductive adhesive that connects the high-voltage side wiring and the high-voltage side electrode and the conductive adhesive that connects the low-voltage side wiring and the low-voltage side electrode.

4. 4. The light emitting device according to claim 3, wherein the second resin formation body is a silicone resin.

5. A light-emitting device described in any one of claims 1 to 4, characterized in that, when viewed in a plan view, the first resin formation body has a shape that is long in the direction in which a gap that electrically separates the high-voltage side wiring and the low-voltage side wiring extends, and short in the direction from the high-voltage side wiring to the low-voltage side wiring.

6. A method for manufacturing a light emitting device including a flip-chip type semiconductor light emitting element, a step of providing a conductive adhesive on each of the high-voltage side wiring and the low-voltage side wiring provided on the surface of the substrate; providing a first resin formation body between the high-voltage side wiring and the low-voltage side wiring; a step of placing the semiconductor light emitting element on the first resin formation body while aligning the high-voltage side electrode of the semiconductor light emitting element with the conductive adhesive on the high-voltage side wiring, and the low-voltage side electrode of the semiconductor light emitting element with the conductive adhesive on the low-voltage side wiring; curing the first resin formation; A method for manufacturing a light-emitting device, comprising the steps of: performing a heat treatment after a step of hardening the first resin formation body, and bonding the high-voltage side electrode and the high-voltage side wiring, and the low-voltage side electrode and the low-voltage side wiring, respectively, via the conductive adhesive.

7. 7. The method for manufacturing a light emitting device according to claim 6, wherein the conductive adhesive contains a flux.

8. 7. The method for manufacturing a light emitting device according to claim 6, wherein in the step of providing the first resin formation body, the first resin formation body is provided inside a region where the semiconductor light emitting element is to be mounted.

9. 7. The method for manufacturing a light emitting device according to claim 6, wherein in the step of applying the conductive adhesive, the conductive adhesive is applied separately to four corners of the region intended to mount the semiconductor light emitting element.

10. a substrate on which a resist is disposed on the high-voltage side wiring and the low-voltage side wiring outside a region where the semiconductor light-emitting element is to be mounted; 7. The method for manufacturing a light-emitting device according to claim 6, wherein in the step of applying the conductive adhesive, the conductive adhesive is applied on each of the high-voltage side wiring and the low-voltage side wiring so that the conductive adhesive extends onto the resist.

11. 7. The method for manufacturing a light-emitting device according to claim 6, characterized in that in the step of providing the first resin formation body, the first resin formation body is arranged so that, when viewed in a plan view, it has a shape that is long in the direction in which the gap that electrically separates the high-voltage side wiring and the low-voltage side wiring extends and short in the direction from the high-voltage side wiring to the low-voltage side wiring.

12. further comprising a resin sealing step of sealing the semiconductor light emitting element with a second resin formed body; The second resin body is made of a material softer than the first resin body, The method for manufacturing a light-emitting device described in claim 6, characterized in that the second resin formation body is formed so as to cover the upper surface of the semiconductor light-emitting element and to penetrate into the area outside the first resin formation body between the conductive adhesive connecting the high-voltage side wiring and the high-voltage side electrode and the conductive adhesive connecting the low-voltage side wiring and the low-voltage side electrode.

13. 13. The method for manufacturing a light emitting device according to claim 12, wherein the second resin formation body is a silicone resin.

14. 14. The method for manufacturing a light emitting device according to claim 6, wherein the first resin formation body is an epoxy resin.

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