WO2017208321A1

WO2017208321A1 - Light-emitting device

Info

Publication number: WO2017208321A1
Application number: PCT/JP2016/065966
Authority: WO
Inventors: 哲二松尾
Original assignee: サンケン電気株式会社
Priority date: 2016-05-31
Filing date: 2016-05-31
Publication date: 2017-12-07
Also published as: JP6269901B1; JPWO2017208321A1

Abstract

The present invention comprises: a support substrate 10; a light-emitting element 20 arranged upon the support substrate 10 and having a laminated structure having a second semiconductor layer 23 arranged above a first semiconductor layer 21; a first electrode 41 arranged in a continuous manner from above a first side surface 101 of the support substrate 10 to above a first side surface 201 of the light-emitting element 20 and electrically connected to the first semiconductor layer 21; and a second electrode 42 arranged in a continuous manner from above a second side surface 102 of the support substrate 10 to above a second side surface 202 of the light-emitting element 20 and electrically connected to the second semiconductor layer 23.

Description

Light emitting device

The present invention relates to a light emitting device to which a chip size package technology is applied.

A chip size package (CSP) is applied to a light emitting device in order to improve the light emission efficiency and miniaturization of the light emitting device using a light emitting element such as a light emitting diode (LED) as a light source (for example, Patent Document 1). reference.). Furthermore, in order to realize a semiconductor light emitting device of extremely small size, the development of a structure in which the semiconductor substrate used for forming the semiconductor layer constituting the light emitting element is separated from the semiconductor layer and the semiconductor layer is enclosed in a package such as a resin is proceeding. It has been.

In a light emitting device to which CSP is applied, an electrode connected to the light emitting element is disposed on a surface opposite to the light extraction surface. For this reason, there is no thing which shields the emitted light of a light emitting element in the direction of a light extraction surface, and the luminous efficiency of a light-emitting device improves.

JP 2014-150196 A

However, since the light emitting element is arranged above the surface where the support substrate and the electrode made of different materials coexist, the light emitting element is distorted due to the difference in linear expansion coefficient of these materials. As a result, problems such as breakage of the light emitting device and deterioration of the performance and product life of the light emitting device occur.

In view of the above problems, an object of the present invention is to provide a light emitting device that can apply CSP and suppress distortion generated in a light emitting element.

According to one embodiment of the present invention, a light-emitting element having a stacked structure in which a support substrate, a second semiconductor layer is disposed above the first semiconductor layer, and the support substrate is disposed; A first electrode disposed continuously from the first side surface over the first side surface of the light emitting element and electrically connected to the first semiconductor layer; and the light emitting element from the second side surface of the support substrate. There is provided a light emitting device that includes a second electrode that is continuously disposed over the second side surface of the first electrode and that is electrically connected to the second semiconductor layer.

According to the present invention, it is possible to provide a light emitting device that can apply CSP and suppress distortion generated in the light emitting element.

It is typical sectional drawing which shows the structure of the light-emitting device which concerns on embodiment of this invention. It is a typical top view which shows the structure of the light-emitting device which concerns on embodiment of this invention. It is another schematic plan view which shows the structure of the light-emitting device which concerns on embodiment of this invention. It is another schematic plan view which shows the structure of the light-emitting device which concerns on embodiment of this invention. It is typical sectional drawing which shows the structure of the light-emitting device of a comparative example. It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on embodiment of this invention (the 1). It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on embodiment of this invention (the 2). It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on embodiment of this invention (the 3). It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on embodiment of this invention (the 4). It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on embodiment of this invention (the 5). It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on embodiment of this invention (the 6). It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on embodiment of this invention (the 7). It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on embodiment of this invention (the 8). It is typical sectional drawing for demonstrating the dicing method in the manufacturing method of the light-emitting device which concerns on embodiment of this invention. It is a typical top view for demonstrating the dicing method in the manufacturing method of the light-emitting device which concerns on embodiment of this invention. It is typical sectional drawing which shows the structure of the light-emitting device which concerns on the modification of embodiment of this invention.

Next, an embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. Further, the embodiments described below exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention includes the shape, structure, arrangement, etc. of components. It is not specified to the following. The embodiment of the present invention can be variously modified within the scope of the claims.

(Embodiment)
As shown in FIG. 1, the light emitting device according to the embodiment of the present invention has a laminated structure in which a support substrate 10 and a second semiconductor layer 23 are disposed above the first semiconductor layer 21. A light emitting element 20 disposed on the first semiconductor layer 21, a first electrode 41 electrically connected to the first semiconductor layer 21, and a second electrode 42 electrically connected to the second semiconductor layer 23. .

The first electrode 41 is continuously arranged from the first side surface 101 of the support substrate 10 to the first side surface 201 of the light emitting element 20. The second electrode 42 is spaced apart from the first electrode 41 and is continuously disposed from the second side surface 102 of the support substrate 10 to the second side surface 202 of the light emitting element 20. Hereinafter, the first electrode 41 and the second electrode 42 are collectively referred to as an “electrode region”.

In the light emitting device shown in FIG. 1, an electrode region for supplying current to the light emitting element 20 is arranged on the side surface of the light emitting element 20. The support substrate 10 is disposed between the first electrode 41 and the second electrode 42 below the light emitting element 20. The support substrate 10 and the electrode region are disposed below the light emitting element 20. There are no boundaries.

The light emitting element 20 has a laminated structure including a first conductive type first semiconductor layer 21 and a second conductive type second semiconductor layer 23. The first conductivity type and the second conductivity type are opposite to each other. That is, if the first conductivity type is P type, the second conductivity type is N type, and if the first conductivity type is N type, the second conductivity type is P type. Hereinafter, a case where the first conductivity type is the P type and the second conductivity type is the N type will be described as an example. For example, the light emitting element 20 is an LED element in which the first semiconductor layer 21 is a P-type cladding layer and the second semiconductor layer 23 is an N-type cladding layer. In the example shown in FIG. 1, a double hetero structure in which a first semiconductor layer 21, a light emitting layer 22, and a second semiconductor layer 23 are stacked is employed for the light emitting element 20.

Holes are supplied from the first electrode 41 to the first semiconductor layer 21, and electrons are supplied from the second electrode 42 to the second semiconductor layer 23. Then, holes are injected from the first semiconductor layer 21 and electrons are injected from the second semiconductor layer 23 into the light emitting layer 22. The injected holes and electrons recombine in the light emitting layer 22 to generate light in the light emitting layer 22.

The light emitting element 20 uses the main surface of the second semiconductor layer 23 as a light extraction surface. Light emitted from the light emitting element 20 passes through the light transmissive substrate 70 disposed above the second semiconductor layer 23 and is output as output light L from the light emitting device. In addition, the electrode region is disposed so as to be exposed on the side surface of the light emitting element 20, and the side surface of the light transmissive substrate 70 is also exposed. That is, the outer side surfaces of the first electrode 41 and the second electrode 42 and the side surface of the light transmissive substrate 70 are at the same plane level.

The first extraction electrode 51 that connects the first semiconductor layer 21 of the light emitting element 20 and the first electrode 41 is electrically connected to the lower surface of the first semiconductor layer 21. The reflective metal layer 30 is disposed on the lower surface of the first semiconductor layer 21, and the first extraction electrode 51 is electrically connected to the first semiconductor layer 21 through the reflective metal layer 30. is doing. The first lead electrode 51 extends in a direction perpendicular to the film thickness direction and is connected to the first electrode 41.

The outgoing light traveling from the light emitting element 20 toward the first semiconductor layer 21 is reflected on the surface of the reflective metal layer 30. That is, the reflective metal layer 30 can reflect the emitted light of the light emitting element 20 traveling in the direction opposite to the light extraction surface toward the light extraction surface. For this reason, the brightness of the output light L can be improved. The reflective metal layer 30 is made of a conductive material that has a high reflectivity with respect to the emitted light of the light emitting element 20 and can make ohmic contact with the first semiconductor layer 21. For example, a white metal film such as a silver-based alloy such as a silver-palladium alloy is preferably used as the material of the reflective metal layer 30.

The second extraction electrode 52 that connects the second semiconductor layer 23 of the light emitting element 20 and the second electrode 42 is electrically connected to the lower surface of the second semiconductor layer 23. As shown in FIG. 1, the second semiconductor layer 23 is a region extending in the horizontal direction to the region where the first semiconductor layer 21 and the light emitting layer 22 are not arranged in plan view (hereinafter referred to as “stretch region”). .) The second extraction electrode 52 is connected to the lower surface of the extended region of the second semiconductor layer 23. The second lead electrode 52 extends in a direction perpendicular to the film thickness direction and is connected to the second electrode 42.

It should be noted that the light emitting element 20, the electrode region, the first extraction electrode 51, and the second extraction electrode 52 are insulated and separated by the protective film 60 disposed so as to cover the side surface and the lower surface of the light emitting element 20. As the protective film 60, for example, a silicon oxide film or a silicon nitride film can be employed. The protective film 60 contributes to suppression of moisture permeation into the light emitting element 20 from the outside and improvement in mechanical strength of the light emitting device.

FIG. 2 shows a plan view of a cross section along the direction II-II in FIG. The light emitting element 20 has a rectangular shape, and the first side surface 201 and the second side surface 202 face each other. The light emitting element 20 and the electrode region are insulated and separated by the protective film 60. A support substrate 10 is formed on the other pair of opposing side surfaces of the light emitting element 20. That is, the light emitting element 20 is disposed in a concave portion constituted by the upper part of the support substrate 10 and the upper part of the electrode region.

FIG. 3 shows a plan view along the III-III direction of FIG. The first extraction electrode 51 and the second extraction electrode 52 are separated by the support substrate 10 and the protective film 60.

FIG. 4 is a plan view taken along the IV-IV direction of FIG. The lower part of the light emitting device has a structure in which the first side surface 101 and the second side surface 102 of the rectangular support substrate 10 facing each other are covered with an electrode region.

The support substrate 10 may be made of an epoxy resin or a silicone resin containing a filler. Moreover, the white support substrate 10 is realizable by adding a white pigment to these resin. According to the white support substrate 10, the reflectance at the support substrate 10 can be improved. As a result, the luminance of the light emitting device is improved.

Although details will be described later, a material having higher mechanical strength than the resin may be used for the support substrate 10. For example, a ceramic substrate is used for the support substrate 10. By using a ceramic substrate having a high mechanical strength for the support substrate 10, the mechanical strength as a package of the light emitting device can be improved.

The light transmissive substrate 70 functions as a sealing material for the light emitting element 20 and a lens of the light emitting device. For example, a thermoplastic resin or a thermosetting resin can be used for the light transmissive substrate 70 as a resin substrate through which light emitted from the light emitting element 20 is transmitted. By using a transparent resin for the light transmissive substrate 70, the output light L having the same color as the light emitted from the light emitting element 20 can be output from the light emitting device.

Alternatively, a phosphor resin containing a phosphor that is excited by the light emitted from the light emitting element 20 and emits the excitation light may be used for the light transmissive substrate 70. By adopting a phosphor resin for the light transmissive substrate 70, the output light L of a desired color can be output from the light emitting device. Moreover, it is also possible to output the output light L in which the light emitted from the light emitting element 20 and the excitation light are mixed from the light emitting device. For example, when the light emitting element 20 having a blue light emission is used, yttrium aluminum garnet (YAG) or the like that emits yellow light when excited by the blue light is used as the phosphor included in the light transmissive substrate 70. . At this time, a part of the blue light emitted from the light emitting element 20 excites the phosphor, thereby converting the wavelength into yellow light. The yellow light emitted from the phosphor and the blue light emitted from the light emitting element 20 are mixed, whereby white output light L is output from the light emitting device. In addition, when the output light L of the light emitting device is other than white light, various combinations of the light emitted from the light emitting element 20 and the phosphor can be employed.

As the transparent resin used for the light transmissive substrate 70, an epoxy resin, a modified epoxy resin, a silicone resin, a modified silicone resin, or the like can be used. For example, in a high-power light-emitting device such as a lighting application, a silicone resin having high heat resistance is used. Moreover, what mixed the fluorescent material in the said transparent resin etc. can be used as fluorescent substance resin.

By the way, the CSP has a structure in which light is extracted from a direction where the electrode region connected to the light emitting element 20 is not arranged. For this reason, since there is no thing which shields the light from a light emitting element in the direction of a light extraction surface, the light emission efficiency of a light-emitting device improves. Moreover, since wire bonding is not used for the electrical wiring of the electrodes, it is possible to suppress problems such as wire breakage and short circuit via the wire. Therefore, the reliability of the light emitting device is improved.

FIG. 5 shows a light emitting device of a comparative example to which CSP is applied. In the light emitting device shown in FIG. 5, the support substrate 10 </ b> A provided with a recess at the top, the light emitting element 20 disposed in the recess of the support substrate 10 </ b> A, and the light transmissive substrate 70 disposed above the light emitting element 20. With. That is, the lower surface and the side surface of the light emitting element 20 are surrounded by the support substrate 10.

As shown in FIG. 5, the first electrode 41A penetrates the lower portion of the support substrate 10A and is connected to the first semiconductor layer 21 via the reflective metal layer 30 in the recess of the support substrate 10A. The second electrode 42A penetrates the lower part of the support substrate 10A at a position away from the position where the first electrode 41A penetrates the support substrate 10A, and the second semiconductor layer 23 extends in the recess of the support substrate 10A. Connected to the area. A protective film 60 is disposed in the remaining area inside the recess of the support substrate 10A.

In the light emitting device shown in FIG. 5, the light emitting element 20 is supported from below by the support substrate 10A, the first electrode 41A, and the second electrode 42A. For this reason, distortion occurs in the light emitting element 20 due to a difference in linear expansion coefficient between the support substrate 10A, the first electrode 41A, and the second electrode 42A.

In contrast, in the light emitting device shown in FIG. 1, there is no boundary between the support substrate 10 and the electrode region below the light emitting element 20. Therefore, according to the light emitting device shown in FIG. 1, the occurrence of distortion in the light emitting element 20 due to the difference in linear expansion coefficient between the support substrate 10 and the electrode region is suppressed.

As described above, in the light emitting device according to the embodiment of the present invention, the electrode region is disposed on the side surface of the light emitting element 20, and the light emitting element 20 is supported from below by the support substrate 10. Since the light emitting element 20 is supported from below by a uniform material, it is possible to suppress stress due to strain on the light emitting element 20. For this reason, breakage of the light emitting device is prevented, and a decrease in performance of the light emitting device and a decrease in product life are suppressed. As a result, according to the light emitting device according to the embodiment, it is possible to provide a light emitting device that can apply CSP and suppress distortion generated in the light emitting element 20. In order to achieve the above effect, it is preferable that the entire lower surface of the light emitting element 20 is covered with the support substrate 10 in plan view.

Hereinafter, a method for manufacturing a light emitting device according to an embodiment of the present invention will be described with reference to FIGS. Note that the manufacturing method of the light-emitting device described below is an example, and it is needless to say that it can be realized by various other manufacturing methods including this modification.

First, as shown in FIG. 6, each layer constituting the light emitting element 20 is formed on the semiconductor substrate 100 having a thickness of about 700 μm by an epitaxial growth method or the like. Specifically, an N-type semiconductor film 230, a light emitting region film 220, and a P-type semiconductor film 210 are sequentially stacked on the semiconductor substrate 100. For the N-type semiconductor film 230, the light emitting region film 220, and the P-type semiconductor film 210, a nitride compound semiconductor layer such as gallium nitride is used. Thereafter, the N-type semiconductor film 230, the light-emitting region film 220, and the P-type semiconductor film 210 are patterned by dry etching to form the second semiconductor layer 23, the light-emitting layer 22, and the first semiconductor layer 21.

Next, a part of the first semiconductor layer 21 and the light emitting layer 22 is removed by a dry etching method or the like, and a part of the second semiconductor layer 23 is exposed. This exposed portion is an extended region to which the second extraction electrode 52 is connected. Next, a protective film 60 is formed so as to cover the exposed first semiconductor layer 21, the extended region of the second semiconductor layer 23, and the light emitting element 20.

Thereafter, as shown in FIG. 7, an opening of the protective film 60 is formed on the first semiconductor layer 21, and the reflective metal layer 30 is formed so as to be connected to the first semiconductor layer 21 through this opening. . Then, the first extraction electrode 51 is formed so as to be connected to the reflective metal layer 30. In addition, an opening of the protective film 60 is formed on the extended region of the second semiconductor layer 23, and the second extraction electrode 52 is formed so as to be connected to the second semiconductor layer 23 through this opening. Note that a gold (Au) film or the like is used for the first extraction electrode 51 and the second extraction electrode 52, but a material that reflects light emitted from the light emitting element 20 is preferably used. For example, an aluminum (Al) film or a silver (Ag) film is also used.

Next, as shown in FIG. 8, the first electrode 41 is formed on the first side surface 201 side of the light emitting element 20 so as to be electrically connected to the first extraction electrode 51. At the same time, the second electrode 42 is formed on the second side surface 202 side of the light emitting element 20 so as to be electrically connected to the second extraction electrode 52. The first electrode 41 and the second electrode 42 are formed by, for example, copper (Cu) plating. Note that the material of the electrode region is selected in consideration of the overall strength of the light emitting device. In addition to Cu plating, an Al material or the like may be used for the electrode region.

Thereafter, as shown in FIG. 9, the gap between the first electrode 41 and the second electrode 42 is embedded so as to cover the protective film 60, the first extraction electrode 51, and the second extraction electrode 52, A support substrate 10 is formed. For example, a transfer mold (TRM) method can be used to form the support substrate 10. The surface of the support substrate 10 is etched in the film thickness direction by a back grinding process until the thickness of the support substrate 10 reaches a predetermined value. Thereby, as shown in FIG. 9, the lower surfaces of the first electrode 41 and the second electrode 42 are exposed below the lower surface of the support substrate 10.

Next, the first connection electrode 81 is formed so as to cover the lower surface of the first electrode 41, and the second connection electrode 82 is formed so as to cover the lower surface of the second electrode 42. The first connection electrode 81 and the second connection electrode 82 (hereinafter collectively referred to as “connection electrode”) are arranged on the mounting substrate when the light emitting device is attached to the mounting substrate such as a printed circuit board. The wiring pattern is used to connect the electrode region of the light emitting device. A solder electrode or the like is preferably used as the connection electrode.

Thereafter, as shown in FIG. 10, a support substrate 110 is formed so as to cover the lower surface of the support substrate 10 and the connection electrodes. The support substrate 110 is formed to reinforce the strength of the base body after the semiconductor substrate 100 is removed because the thickness of the base body on which the light emitting element 20 and the support substrate 10 are stacked is only several tens of μm. For example, a silicon substrate or a ceramic substrate having a thickness of about 1 mm is bonded to the base body as the support substrate 110.

Thereafter, as shown in FIG. 11, the semiconductor substrate 100 is removed from the base. For example, when the semiconductor substrate 100 is a silicon substrate, the semiconductor substrate 100 is deleted by wet etching using hydrofluoric acid. When the semiconductor substrate 100 is a sapphire substrate, a laser lift-off method or the like is used.

In addition, as shown in FIG. 12, you may form an uneven structure in the main surface of the 2nd semiconductor layer 23 exposed by deletion of the semiconductor substrate 100. FIG. By roughening the surface of the light extraction surface of the light emitting element 20 in this way, the emitted light of the light emitting element 20 is scattered and the luminance of the output light L can be improved. The uneven structure is formed by, for example, dry etching using a pattern formed by a photomask or nanoimprint.

Thereafter, as shown in FIG. 13, a light transmissive substrate 70 is formed on the second semiconductor layer 23. Then, after the singulation process for individually separating the light emitting devices by dicing, the support substrate 110 is removed. Thus, the light emitting device shown in FIG. 1 is completed.

According to the method of manufacturing the light emitting device according to the embodiment of the present invention as described above, the electrode region is formed on the side surface of the light emitting element 20 and the entire light emitting element 20 is supported by the support substrate 10 from below. realizable. For this reason, it is suppressed that the stress by distortion is added to the light emitting element 20.

In a light emitting device using a conventional package that is not a CSP, a semiconductor layer is stacked on a semiconductor substrate to form the light emitting element 20, and the semiconductor substrate is used as a support substrate. On the other hand, in the light emitting device to which CSP is applied, the support substrate 10 is formed by applying resin or the like to the wafer on which the light emitting element 20 is formed. Thus, by forming a package in a wafer state, a light emitting device can be manufactured at low cost. For this reason, it is generally called a wafer level package (WLP).

A structural feature of WLP is that the support substrate 10 is formed so as to be in direct contact with the light emitting element 20 or in direct contact with the protective film 60 and the electrode region formed in the light emitting element 20. Since the package is in contact with the light emitting element 20, the mechanical strength of the light emitting element 20 can be reinforced and a highly reliable light emitting device can be realized. Further, since the semiconductor substrate is removed, the height of the light emitting device can be reduced. Furthermore, the light extraction efficiency from the light emitting element 20 is improved by removing the semiconductor substrate.

<Modification>
Although the example in which the support substrate 10 is a resin has been described above, it is preferable to use a material having higher mechanical strength than the resin for the support substrate 10. This is because, in a light emitting device to which CSP is applied, the semiconductor substrate is deleted, and a transparent resin having a low mechanical strength such as an epoxy resin or a silicone resin is used on the light extraction surface, so that the mechanical strength of the entire package is low. For this reason, it is preferable to increase the mechanical strength of the entire package by using a material having high mechanical strength for the support substrate 10. On the other hand, if the mechanical strength of the package is low, there is a risk that the light emitting device may be damaged when it is incorporated into the product substrate or after it is incorporated. In addition, it is necessary to take measures such as devising the configuration of the built-in device or slowing down the built-in speed so that the light emitting device is not damaged.

For this reason, for example, using a ceramic substrate for the support substrate 10 is effective in increasing the mechanical strength of the light emitting device. In order to use the support substrate 10 as a ceramic substrate, in the step of forming the support substrate 10 described with reference to FIG. 9, a liquid ceramic material is formed into a predetermined shape and then baked at a high temperature.

By using a ceramic substrate for the support substrate 10, the mechanical strength of the light emitting device is improved. Furthermore, since the ceramic substrate is disposed so as to support substantially the entire lower surface of the light emitting element 20, it is possible to prevent the light emitting element 20 from being damaged due to distortion during manufacturing in a process of removing the semiconductor substrate 100 or the like. Further, it is possible to prevent the light emitting element 20 from being damaged by an impact applied to the light emitting device during product assembly or handling. As described above, by using the support substrate 10 as the ceramic substrate, it is possible to suppress damage to the light emitting device and deterioration of reliability. In addition, it is possible to suppress damage due to thermal distortion caused by solder heat treatment during product assembly.

However, in the case of a ceramic substrate, polishing processing (back grinding) after forming the ceramic substrate is more difficult than the resin substrate. Therefore, in the step of forming the support substrate 10, the support substrate 10 is formed so that the lower surface of the first electrode 41 and the lower surface of the second electrode 42 are positioned below the lower surface of the support substrate 10. For example, the step between the lower surface of the support substrate 10 and the lower surface of the electrode region is set to about 10 μm. Thereby, the polishing process of the ceramic substrate after the ceramic substrate is formed as the support substrate 10 becomes unnecessary. For this reason, the damage which the polishing process gives to the support substrate 10 and the light emitting element 20 can be reduced. As a result, a decrease in yield and reliability of the light emitting device can be suppressed.

In the light emitting device shown in FIG. 1, since the electrode region is formed on the side surface of the light emitting element 20, in dicing for singulation processing, as shown in FIGS. 14 and 15, the region cut by the dicing blade 200. The electrode region is mainly cut from the support substrate 10. For this reason, when the support substrate 10 is a material harder than an electrode area | region, such as when using a ceramic substrate, the processing time of dicing decreases. Further, since the life of the dicing blade is extended, the manufacturing cost can be reduced.

Note that the stress applied to the light emitting element 20 greatly affects the characteristics of the light emitting device. In particular, since the light emitting device to which the CSP is applied has a structure in which the light emitting element 20 is in close contact with the package material, stress is easily applied to the light emitting element 20 due to a difference in linear expansion coefficient from the package material or deformation during processing.

Therefore, as shown in FIG. 16, the first ceramic layer 11 and the second ceramic layer 12 having a higher density and a larger linear expansion coefficient than the first ceramic layer 11 are laminated on the support substrate 10. A ceramic substrate having a structure may be used. As shown in FIG. 16, the light emitting element 20 is disposed on the first ceramic layer 11 having a small linear expansion coefficient. As described above, by bringing the semiconductor layer constituting the light emitting element 20 and the first ceramic layer 11 having a linear expansion coefficient close to each other, distortion when curing the ceramic is alleviated and stress applied to the light emitting element 20 is reduced. be able to. Further, the second ceramic layer 12 having a large linear expansion coefficient is provided on the side of the support substrate 10 that is far from the light emitting element 20, so that the warp of the support substrate 10 is suppressed and the strength of the entire package is prevented from being lowered. it can. Therefore, by using the support substrate 10 having the structure shown in FIG. 16, a highly reliable and highly efficient light-emitting device can be realized. In order to reduce the linear expansion coefficient and elastic modulus of the first ceramic layer 11, for example, there is a method of increasing the porosity.

Further, when a glass substrate is used as the light-transmitting substrate 70, the glass substrate has a high elastic coefficient and a large linear expansion coefficient, so that a large stress is generated in the light emitting element 20. In this case, by making the linear expansion coefficient of the first ceramic layer 11 smaller than the linear expansion coefficient of the second ceramic layer 12, the linear expansion coefficient of the first ceramic layer 11 can be made closer to glass, The stress applied to the light emitting element 20 can be reduced.

(Other embodiments)
As mentioned above, although this invention was described by embodiment, it should not be understood that the description and drawing which form a part of this indication limit this invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

For example, there may be a portion where the outer edge portion of the lower surface of the light emitting element 20 overlaps the electrode region. In other words, the outer edge portion of the light emitting element 20 may overlap the electrode region in a plan view as long as the stress that destroys the light emitting element 20 or deteriorates the performance is not applied to the light emitting element 20.

Thus, it goes without saying that the present invention includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

The semiconductor device of the present invention can be used for a light emitting device to which CSP is applied.

Claims

A support substrate;
A light emitting device having a stacked structure in which a second semiconductor layer is disposed above the first semiconductor layer, and disposed on the support substrate;
A first electrode disposed continuously from the first side surface of the support substrate to the first side surface of the light-emitting element and electrically connected to the first semiconductor layer;
A second electrode that is disposed continuously from the second side surface of the support substrate to the second side surface of the light-emitting element and is electrically connected to the second semiconductor layer. Light-emitting device.
A protective film covering at least a part of the light emitting element;
The light emitting device according to claim 1, wherein the support substrate is in contact with at least one of the light emitting element and the protective film.
2. The light emitting device according to claim 1, wherein the support substrate is made of a material harder than the first electrode and the second electrode.
The light-emitting device according to claim 1, wherein the lower surface of the light-emitting element is entirely covered with the support substrate in a plan view.
The light-emitting device according to claim 1, wherein the support substrate is a ceramic substrate.
The light emitting device according to claim 5, wherein the lower surface of the first electrode and the lower surface of the second electrode are located below the lower surface of the support substrate.
The ceramic substrate is
A first ceramic layer;
2. A structure in which a second ceramic layer having a larger linear expansion coefficient than the first ceramic layer is laminated, and the light emitting element is disposed on the first ceramic layer. Item 6. The light emitting device according to Item 5.
A light-transmitting substrate disposed above the light-emitting element;
2. The light emitting device according to claim 1, wherein an outer side surface of the first electrode and the second electrode and a side surface of the light transmissive substrate are on the same plane level.