JP4958273B2 - Light emitting device and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting apparatus which has high reliability and is smaller, and a manufacturing method thereof. <P>SOLUTION: A light-emitting device (LED) made of an N-type semiconductor layer 2, a P-type semiconductor layer 3 and pad electrodes 4a, 4b, etc., is formed on the surface of a first semiconductor substrate 1 made of gallium arsenide (GaAs), etc. Insulating films 5 such as a silicon nitride film are formed on the side and rear surfaces of the first semiconductor substrate 1. Wiring layers 6 connected to the pad electrodes 4a, 4b are formed on the insulating films 5 along one part of the side and rear surfaces of the first semiconductor substrate 1. A protective layer 7 is formed so as to cover the insulating films 5 and the wiring layers 6. An opening is formed on a predetermined region of the protective layer 7, and ball-like conductive terminals 8 are formed on the wiring layer 6 in the opening. A second semiconductor substrate 11 having an opening 10 penetrating from the front surface to the rear surface is stuck on the first semiconductor substrate 1 via an adhesive 12 such as an epoxy resin, etc. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a light emitting device, and more particularly to a chip size package type light emitting device and a manufacturing method thereof.

  A light emitting diode (LED) is widely used as a light emitting element because it can stably generate light with a relatively small electric power for a long time. An apparatus including a light emitting element (hereinafter referred to as a light emitting apparatus) will be described with reference to FIG.

  The conventional light emitting device 100 is electrically connected to the front surface electrode of the LED chip 102 via the bonding wire 103 and the LED chip 102 having the front surface electrode and the back surface electrode disposed on the first lead 101 (cathode). Second lead 104 (anode). The portion of the first lead 101 where the LED chip 102 is disposed is processed into a concave shape. For example, silver plating is applied to the concave surface portion 105. Therefore, the concave surface portion 105 functions as a light reflecting surface and has a light collecting effect, so that the brightness of the LED is improved. In addition, each configuration described above is sealed with a transparent resin layer 106.

  Such light emission and turn-off control of the light emitting device 100 is performed by supplying a predetermined voltage to the first lead 101 and the second lead 104 from a driving device (not shown) different from the light emitting device 100. Is called.

Techniques related to the present invention are described in, for example, the following patent documents.
JP 2003-318447 A Japanese Patent Laid-Open No. 2003-347583

  However, in the above-described conventional structure, it is difficult to make the components such as the first lead 101 and the bonding wire 103 having the concave surface portion 105 fine, and it is necessary to seal them entirely with the transparent resin layer 106. There is also. In addition, a device for driving the light emitting device 100 is required separately. For these reasons, the conventional structure has a problem that the entire apparatus cannot be reduced in size and thickness.

  Also, after completing each component separately, assembly work (for example, a step of placing the LED chip 102 on the first lead 101, a step of connecting the LED chip 102 and the second lead 104 with the bonding wire 103, And the like, a process of sealing the whole with the transparent resin 106, etc.) is necessary, so that the manufacturing process is complicated and the cost is increased.

  Accordingly, an object of the present invention is to provide a light-emitting device with high reliability and a smaller size, and a method for manufacturing the same.

  The present invention has been made in view of the above problems, and its main features are as follows. That is, the light emitting device of the present invention includes a first substrate having a light emitting element formed on the front surface, and a second substrate having an opening penetrating from the front surface to the back surface, and the surface side of the first substrate. And the surface side of the second substrate face each other and are bonded together through an adhesive layer, and light of the light emitting element is radiated to the outside through the opening.

  The light emitting device of the present invention is characterized in that a device element is formed on the surface of the second substrate.

Further, the method for manufacturing a light emitting device of the present invention includes a first substrate having a light emitting element formed on a surface,
Preparing a second substrate, facing the surface side of the first substrate and the surface side of the second substrate, and bonding them together via an adhesive layer, before the bonding step or A step of forming an opening through the second substrate from the front surface side to the rear surface side and transmitting light emitted from the light emitting element, the first substrate and the second substrate along a predetermined dicing line; The method includes cutting the second substrate and dividing it into individual chips.

  Further, the method includes a step of forming a device element on the surface of the second substrate.

  In the light-emitting device of the present invention, a first substrate having a light-emitting element formed on a surface and a second substrate having an opening are bonded to each other, and light from the light-emitting element is emitted to the outside through the opening. It is the composition which becomes. Therefore, the light emitting device can be configured as an integrated chip from the state of the wafer before being divided into individual devices, and a thinner and smaller light emitting device can be realized.

  Further, according to the manufacturing method of the present invention, a plurality of parts are completed separately, and the chip that has undergone subsequent assembly work is completed with an integrated chip. Therefore, steps such as subsequent assembly work can be omitted, and workability and productivity of the light emitting device can be improved.

  A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a light emitting device according to a first embodiment of the present invention.

  For example, an N-type semiconductor layer 2 and a P-type semiconductor layer 3 are formed on the surface of an N-type first semiconductor substrate 1 made of gallium arsenide (GaAs) or gallium nitride (GaN). A PN junction region formed by these layers is a light emitting region. A pad electrode 4 a (cathode electrode) is formed on the N-type semiconductor layer 2, and a pad electrode 4 b (anode electrode) is formed on the P-type semiconductor layer 3.

  An insulating film 5 such as a silicon oxide film or a silicon nitride film is formed on the side surface and the back surface of the first semiconductor substrate 1. On the insulating film 5, a wiring layer 6 connected to the pad electrodes 4 a and 4 b is formed along a part of the side surface and the back surface of the first semiconductor substrate 1. A protective layer 7 made of a solder resist or the like is formed so as to cover the insulating film 5 and the wiring layer 6. An opening is formed in a predetermined region of the protective layer 7, and a ball-like conductive terminal 8 is formed on the wiring layer 6 in the opening.

  On the first semiconductor substrate 1, a second semiconductor substrate 11 (for example, made of silicon (Si) or the like) having an opening 10 penetrating from the front surface to the back surface has an adhesive layer 12 such as an epoxy resin. Are pasted together. Note that the outer periphery on the front surface side of the second semiconductor substrate 11 is chamfered obliquely from the first semiconductor substrate 1 side, and a notch 13 is formed. In addition, since the manufacturing method of the light-emitting device which concerns on 1st Embodiment is contained in the manufacturing method of 2nd Embodiment mentioned later, description is abbreviate | omitted.

  In the light emitting device according to the first embodiment, a plurality of components such as an LED chip, a lead, and a bonding wire are individually formed and then combined, as in the conventional structure (see FIG. 20), The structure is integrated as a chip. In addition, since the constituent elements of the light emitting device are formed by a wafer process, each element can be formed finely. Therefore, it is possible to reduce the size of the light emitting device as compared with the conventional case.

  In addition, according to the present embodiment, a plurality of components that have been manufactured separately and completed as a light emitting device through subsequent assembly work are integrated into one chip when divided into individual chips. To do. Therefore, steps such as subsequent assembly work can be omitted, and the productivity of the light emitting device can be improved.

  Further, if the material of the substrate (second semiconductor substrate 11) on the side where the opening 10 is formed as in the present embodiment is silicon, the concave surface portion 105 subjected to processing such as plating as in the conventional example. Even without (see FIG. 20), since the inner peripheral portion of the opening 10 functions as a reflecting surface, the directivity and brightness of light emitted from the light emitting element can be improved. Therefore, the conventional process of forming the concave surface portion 105 is not required, and the manufacturing process can be simplified. Even when a substrate made of a material with poor reflection efficiency is used in place of the second semiconductor substrate 11, it is sufficient to perform a treatment such as metal plating such as gold plating or silver plating on the inner periphery of the opening 10. Reflection efficiency can be obtained and the luminance can be improved.

  Next, a second embodiment of the present invention will be described. 2 to 14 are sectional views or plan views respectively shown in the order of the manufacturing process.

  First, as shown in FIG. 2, a second semiconductor substrate 41 made of, for example, silicon (Si) having a device element 40 formed on the surface is prepared. The device element 40 has no limitation on the type and function of the element, and includes, for example, a drive element that controls light emission and extinction of a light emitting element formed on the first semiconductor substrate 21 described later. The thickness of the second semiconductor substrate 41 is, for example, about 300 μm to 700 μm.

  Next, a first insulating film 42 (for example, a silicon oxide film formed by a thermal oxidation method, a CVD method, or the like) is formed on the surface of the second semiconductor substrate 41 to a thickness of 2 μm, for example. Next, a metal layer such as aluminum (Al), an aluminum alloy, or copper (Cu) is formed by a sputtering method, a plating method, or another film formation method, and then the metal layer is selectively etched to form a first insulating layer. A pad electrode 43 is formed on the film 42 to a thickness of 1 μm, for example. The pad electrode 43 is an electrode electrically connected to the device element 40 and its peripheral elements via a wiring (not shown). The position of the pad electrode 43 is not limited and can be disposed on the device element 40. Further, the pad electrode 43 can also be arranged so as to surround the outer periphery of the finally completed device.

  Next, a passivation film (not shown) (for example, a silicon nitride film formed by a CVD method) that covers part or all of the pad electrode 43 is formed on the surface of the second semiconductor substrate 41 as necessary. .

  Next, as shown in FIG. 3, a predetermined region of the second semiconductor substrate 41 is selectively removed by, for example, a dry etching method to form an opening 44 penetrating the substrate. The opening 44 is a part serving as a path of light emitted from the first semiconductor substrate 21 side described later. In addition, the opening 44 is formed by oblique etching so that the opening diameter increases from the front surface side to the back surface side of the second semiconductor substrate 41, thereby improving light reflection efficiency and improving directivity and luminance. Preferred above. In addition, you may form after the bonding process of the 1st semiconductor substrate 21 mentioned later and the 2nd semiconductor substrate 41, without forming the opening part 44 at this time.

  Next, a light emitting element is formed. In the present embodiment, a light emitting diode (LED) is formed on the first semiconductor substrate 21. First, as shown in FIG. 4, an N-type first semiconductor substrate 21 made of, for example, gallium arsenide (GaAs) or gallium nitride (GaN) is prepared. The thickness of the first semiconductor substrate 21 is, for example, about 300 μm to 700 μm. The material of the first semiconductor substrate 21 can be changed as appropriate according to the intended color of light emission. Next, an N-type semiconductor layer 22 and a P-type semiconductor layer 23 are sequentially formed on the surface of the first semiconductor substrate 21 by a known epitaxial crystal growth method. The PN junction region by these becomes a light emission region. The N-type impurity added to the first semiconductor substrate 21 and the N-type semiconductor layer 22 is, for example, sulfur (S), selenium (Se), tellurium (Te), or the like. The P-type impurity added to the P-type semiconductor layer 23 is, for example, zinc (Zn).

  Next, a part of the P-type semiconductor layer 23 is selectively removed by, for example, a dry etching method to expose a part of the N-type semiconductor layer 22 as shown in FIG. Next, pad electrodes 24 a (cathode electrodes) and 24 b (anode electrodes) are formed on the exposed N-type semiconductor layer 22 and P-type semiconductor layer 23, respectively. For the pad electrodes 24a and 24b, a metal layer such as aluminum (Al) or copper (Cu) is formed by a thin film formation technique such as sputtering, and then the metal layer is selectively used using a resist layer (not shown) as a mask. It is formed by etching.

  Next, if necessary, an insulating film that covers the entire surface of the first semiconductor substrate 21 may be formed by, for example, a CVD method, and the insulating films on the pad electrodes 24a and 24b may be removed by photolithography. That is, the surfaces of the N-type semiconductor layer 22 and the P-type semiconductor layer 23 may be covered with an insulating film or may be exposed. Thus, a light emitting element is formed on the surface of the first semiconductor substrate 21. Note that the above description using FIGS. 4 and 5 is an example of a method for manufacturing a light-emitting element, and the manufacturing process differs depending on required characteristics (emission color, etc.). The light emitting element may be any element that emits light, and may be a laser diode.

  Next, as shown in FIGS. 6A and 6B, the surface side of the first semiconductor substrate 21 (elements) via an adhesive layer 25 such as epoxy resin, polyimide (for example, photosensitive polyimide), resist, acrylic, or the like. The surface side) and the surface side (element surface side) of the second semiconductor substrate 41 are bonded together. The thickness of the adhesive layer 25 is about several μm to several tens of μm. Therefore, the element (light emitting element) on the first semiconductor substrate 21 and the element (device element 40) on the second semiconductor substrate 41 are close to each other. The adhesive layer 25 is transparent and has a property that allows light to pass therethrough. As shown in FIG. 7, the first semiconductor substrate 21 and the second semiconductor substrate 41 in the present embodiment are bonded so that the pad electrodes 24 a and 24 b and the pad electrode 43 do not overlap. FIG. 7 is a schematic plan view showing a part of the bonding surface, FIG. 6A corresponds to a cross-sectional view taken along line XX in FIG. 7, and FIG. 6B shows YY. It corresponds to a cross-sectional view along the line. In the following, description will be made using respective cross-sectional views as in FIGS.

  Next, back grinding is performed on the back surface of the first semiconductor substrate 21 using a back surface grinding device (grinder), and the thickness of the first semiconductor substrate 21 is set to a predetermined thickness (for example, about 50 to 100 μm). make it thin. The grinding process may be an etching process, or a combination of a grinder and an etching process. Depending on the use and specifications of the final product and the initial thickness of the prepared first semiconductor substrate 21, the grinding step may not be necessary. Moreover, since a grinding surface may be roughened when the said grinding process is performed, you may perform a wet etching process as a process for obtaining a flat surface after a grinding process, for example.

  Next, as shown in FIGS. 8A and 8B, predetermined regions corresponding to the pad electrodes 24 a and 24 b in the first semiconductor substrate 21 are selectively selected from the back surface side of the first semiconductor substrate 21. Etching is performed to expose part of the pad electrodes 24 a and 24 b and the adhesive layer 25. Hereinafter, this exposed portion is referred to as an opening 26.

  The selective etching of the first semiconductor substrate 21 will be described with reference to FIGS. 9A and 9B are schematic plan views of a part of the wafer state configuration as viewed from the first semiconductor substrate 21 side, and FIG. 8A is a view of FIGS. 9A and 9B. FIG. 8B corresponds to the cross-sectional view along the YY line.

  As shown in FIG. 9A, the first semiconductor substrate 21 can be etched into a substantially rectangular shape that is narrower than the width of the second semiconductor substrate 41. Further, as shown in FIG. 9B, only the region where the pad electrodes 24a, 24b, and 43 are formed is etched so that the outer periphery of the first semiconductor substrate 21 becomes uneven. it can. In the latter case, the overlapping area of the first semiconductor substrate 21 and the second semiconductor substrate 41 is larger, and the first semiconductor substrate 21 remains close to the outer periphery of the second semiconductor substrate 41. Therefore, from the viewpoint of improving the adhesive strength between the first semiconductor substrate 21 and the second semiconductor substrate 41, the latter configuration is preferable. Note that the first semiconductor substrate 21 can be designed in a shape different from the planar shape shown in FIGS.

  In the present embodiment, as shown in FIGS. 8A and 8B, the side walls are etched obliquely so that the lateral width of the first semiconductor substrate 21 increases toward the surface side. Note that etching can be performed so that the side wall of the first semiconductor substrate 21 is perpendicular to the main surface of the second semiconductor substrate 41.

  Next, as shown in FIGS. 10A and 10B, a second insulating film 27 is formed in the opening 26 and on the back surface of the first semiconductor substrate 21. The second insulating film 27 is an insulating film such as a silicon oxide film or a silicon nitride film formed by a plasma CVD method, for example.

  Next, as shown in FIG. 11A, the second insulating film 27 is selectively etched using a resist layer (not shown) as a mask. By this etching, the second insulating film 27 formed from the pad electrodes 24 a and 24 b to the region from the individual chip boundary (so-called dicing line DL) is removed, and the pad electrodes 24 a and 24 b are formed at the bottom of the opening 26. At least a portion is exposed. The second insulating film 27 is an inorganic film, and the adhesive layer 25 is an organic film. By utilizing such a film difference, the adhesive layer 25 is not removed at this point.

  Next, as shown in FIG. 11B, a part of the adhesive layer 25 at the bottom of the opening 26 is selectively etched using a resist layer (not shown) as a mask. By this etching, a part of the adhesive layer 25 is removed at the bottom of the opening 26 and at least a part of the pad electrode 43 is exposed. Thus, both the pad electrodes 24a and 24b on the first semiconductor substrate 21 side and the pad electrode 43 on the second semiconductor substrate 41 side are exposed.

  Next, a conductive layer such as aluminum (Al) or copper (Cu) to be the wiring layers 28 and 29 is formed with a film thickness of 1 μm, for example, by sputtering, plating, or other film forming methods. Thereafter, the conductive layer is selectively etched using a resist layer (not shown) as a mask. By this etching, the conductive layers become wiring layers 28 and 29 formed along the side surfaces of the first semiconductor substrate 21 with the second insulating film 27 interposed therebetween, as shown in FIGS. . As shown in FIG. 12A, the wiring layer 28 is connected to at least a part of the pad electrodes 24 a and 24 b and extends on a part of the back surface of the first semiconductor substrate 21. As shown in FIG. 12B, the wiring layer 29 is connected to at least a part of the pad electrode 43 and extends on a part of the back surface of the first semiconductor substrate 21.

  In addition to the formation process of the wiring layers 28 and 29, as shown in FIG. 14, a wiring layer 36 for connecting the pad electrodes 24a and 24b and the pad electrode 43 to each other is formed. As a result, a light emitting element composed of the N-type semiconductor layer 22 and the P-type semiconductor layer 23 formed on the surface of the first semiconductor substrate 21 and a device element formed on the surface of the second semiconductor substrate 41. 40 is electrically connected. Note that the electrical connection between the light emitting element and the device element 40 may be performed by wiring on the mounting substrate side without forming the wiring layer 36.

  Next, it is preferable to form the cutout portion 30 by removing a part of the adhesive layer 25 and the second semiconductor substrate 41 from the first semiconductor substrate 21 side by a dicing blade or etching. Note that the cross-sectional shape of the notch 30 is not limited to the V shape as shown in FIGS. 12A and 12B as long as the notch 30 reaches the second semiconductor substrate 41, and an elliptical shape. Or a substantially rectangular shape.

  Next, it is preferable to form an electrode connection layer (not shown) that covers the wiring layers 28 and 29. The electrode connection layer is formed because the wiring layers 28 and 29 made of aluminum or the like and the conductive terminals 32 made of solder or the like, which will be described later, are difficult to join, and the material of the conductive terminals 32 is on the wiring layers 28 and 29 side. This is because the inflow is prevented. The electrode connection layer can be formed by, for example, a lift-off method or a plating method in which a metal layer such as a nickel (Ni) layer and a gold (Au) layer is sequentially sputtered using the resist layer as a mask and then the resist layer is removed. .

  Next, as shown in FIGS. 13A and 13B, a protective layer 31 having an opening in a formation region of a conductive terminal 32 described later is formed with a thickness of, for example, 10 μm. The protective layer 31 is formed as follows, for example. First, an organic material such as polyimide resin or solder resist is applied to the entire surface by a coating / coating method, and heat treatment (pre-baking) is performed. Next, the applied organic material is exposed and developed to form an opening that exposes a predetermined region, and then a heat treatment (post-bake) is applied thereto. Thereby, the protective layer 31 having an opening in the formation region of the conductive terminal 32 is obtained. In this embodiment, since the notch 30 is formed, the side surface of the adhesive layer 25 is completely covered with the protective layer 31. For this reason, it is possible to prevent the adhesive layer 25 from coming into contact with the outside air and to prevent the entry of corrosive substances (for example, moisture) into the device element 40 and the adhesive layer 25.

  Next, a conductive material (for example, solder) is screen-printed on an electrode connection layer (not shown) exposed from the opening of the protective layer 31, and the conductive material is reflowed by heat treatment. Thus, as shown in FIGS. 13A and 13B, the conductive terminals 32 electrically connected to the pad electrodes 24a, 24b, 43 via the wiring layers 28, 29 are formed on the back surface of the first semiconductor substrate 21. It is formed. The method for forming the conductive terminal 32 is not limited to the above, and it may be formed by an electrolytic plating method or a so-called dispensing method (coating method) in which solder or the like is applied to a predetermined region using a dispenser. The conductive terminal 32 may be made of gold, copper, or nickel, and the material is not particularly limited. Further, the step of forming the electrode connection layer (not shown) may be performed after the formation of the protective layer 31.

  Next, it is cut along a predetermined dicing line DL and divided into individual light emitting devices 35. As a method of dividing into individual light emitting devices 35, there are a dicing method, an etching method, a laser cut method, and the like. FIG. 14 is a schematic plan view of the light emitting device 35 as viewed from the back side (first semiconductor substrate 21 side). Note that the light emitting device 35 in FIGS. 13A and 13B corresponds to a cross-sectional view taken along lines XX and YY in FIG.

  Through the above steps, a chip size package type light emitting device 35 having both the light emitting element (LED) and the device element 40 on the bonding surface of the first semiconductor substrate 21 and the second semiconductor substrate 41 is completed. The light emitting device 35 is mounted on a printed circuit board or the like via the conductive terminal 32. The light from the light emitting device 35 is reflected by the inner peripheral surface of the opening 44 and radiated to the second semiconductor substrate 41 side, as indicated by arrows in FIGS.

  In the second embodiment, a plurality of components (LED chips, leads, bonding wires) are individually formed as in the conventional structure (see FIG. 20), and are not configured afterward, but are divided into individual devices. It is integrated as a chip through an adhesive layer from before the wafer state, that is, from the wafer state. Furthermore, the 1st semiconductor substrate 21 provided with a light emitting element and the 2nd semiconductor substrate 41 provided with the device element 40 are integrated. Therefore, it is possible to reduce the size of the light emitting device as compared with the conventional case, and it is possible to efficiently mount many elements in one chip, and to obtain a multifunctional light emitting device. For example, as in this embodiment, a light emitting element is formed on the first substrate side, and a driving element for controlling the light emitting element is provided on the second substrate side. It can be realized with a chip. Therefore, it is not necessary to form a driving device separately from the light emitting device as in the conventional case (FIG. 20).

  Furthermore, according to the present embodiment, even if it is conventionally not mixed and sealed on one chip, or it is difficult to mount and seal on one chip for reasons such as a manufacturing process. The elements can be formed separately on the first substrate and the second substrate and sealed with one chip. Therefore, it is possible to reduce the size of the entire apparatus as compared with the conventional case. For example, since MEMS (Micro Electro Mechanical Systems) is generally formed by high-temperature processing, the compatibility with a CMOS process or the like is not good. MEMS is a device in which mechanical element parts, sensors, actuators, electronic circuits and the like are integrated on a semiconductor substrate. For this reason, it has been difficult in the conventional manufacturing process to form the MEMS and other elements (for example, a driving element for MEMS) in a single chip. However, as in the second embodiment, a MEMS is formed on one substrate, and a driving element and a light emitting element of the MEMS are formed on the other substrate, thereby forming a light emitting device including the MEMS on a single chip. be able to.

  Also, according to the present embodiment, a plurality of parts that have been conventionally manufactured separately and assembled are integrated and completed when the wafer-like substrate is divided into individual chips. Therefore, subsequent assembly work and the like can be omitted, and workability can be improved.

  Next, a third embodiment of the present invention will be described. FIGS. 15A and 15B are cross-sectional views of the light emitting device 50 according to the third embodiment. FIG. 16 is a schematic plan view of the light emitting device 50 as viewed from the second semiconductor substrate 41 side. 15A and 15B corresponds to a cross-sectional view taken along lines AA and BB in FIG. Note that the third embodiment will be described using two cross-sectional views similarly to the second embodiment, and the description of the same configuration as the first and second embodiments will be omitted or simplified.

  In the light emitting device 50 according to the third embodiment, a plurality of P-type semiconductor layers 51 are arranged on the N-type semiconductor layer 22 in, for example, a matrix as shown in FIGS. Each P-type semiconductor layer 51 is partitioned by an insulating layer 52 formed on the N-type semiconductor layer 22. Such a plurality of P-type semiconductor layers 51 can be formed, for example, by forming a P-type semiconductor layer uniformly and then performing a known photolithography process.

  The upper part of each P-type semiconductor layer 51 is connected to a conductive layer 53 (anode electrode) made of aluminum or the like. Each conductive layer 53 is electrically connected to the wiring layer 28 formed along the side surface and the back surface of the first semiconductor substrate 21 and the conductive terminal 32. With this configuration, each P-type semiconductor layer 51 forming portion emits light independently. In other words, a plurality of light emitting portions are formed on the first semiconductor substrate 21.

  The second semiconductor substrate 41 has a plurality of openings 54, and the openings 54 are formed at positions corresponding to the plurality of light emitting portions described above. The opening 54 serves as a path for light emitted from the light emitting unit.

  A conductive terminal 56 (cathode electrode) is formed on the back surface of the first semiconductor substrate 21 via an electrode connection layer 55 (for example, a laminate of an aluminum layer, a nickel layer, and a gold layer). As described above, the cathode electrode may be formed on the back surface of the first semiconductor substrate 21. As described above, the light emitting device 50 supplies a voltage to the P-type region (P-type semiconductor layer 51) from the conductive terminal 32 via the conductive layer 53, and thus the N-type region (the first semiconductor substrate 21 and the N-type semiconductor layer 22). ), When a voltage is supplied via the conductive terminal 56, the PN junction surface emits light.

  A device element 40 is formed on the surface of the second semiconductor substrate 41. The device element 40 is connected to the conductive layer 53 and the conductive terminal 56 through the pad electrode 43, and includes, for example, a drive element that outputs a signal for selectively emitting and turning off the plurality of light emitting units described above.

  In the first and second embodiments, the P-type semiconductor layers 3, 23 are formed substantially uniformly on the surfaces of the first semiconductor substrates 1, 21, and the second semiconductor substrates 16, 41 have one Only one opening 10, 44 was formed. On the other hand, in the third embodiment, a plurality of light emitting units are formed on the first semiconductor substrate 21, and light emission and extinction of each light emitting unit can be selectively controlled. Therefore, in addition to the effects obtained in the first and second embodiments, various images (still images and moving images) including numerals (Arabic numerals, Chinese numerals, Roman numerals, etc.) and letters (Hiragana, Katakana, Kanji, etc.) Can be displayed on a single chip. Further, it is preferable that adjacent light emitting portions are partitioned by the formation of the plurality of openings 54. Therefore, the directivity of light is good and suitable for a light emitting module.

  Needless to say, the present invention is not limited to the above-described embodiment, and can be changed without departing from the gist thereof. For example, as shown in FIG. 17, a predetermined lens 60 made of a resin such as epoxy or silicone, glass or the like can be disposed in the opening 10 to further improve the light directivity and brightness. Further, since the opening 10 is used as a space for arranging the lens 60, an increase in size of the apparatus due to the lens arrangement is suppressed. In addition, as in the third embodiment, a lens can be disposed in each of the plurality of openings 54. Moreover, it is preferable from a viewpoint of size reduction that the lens arrange | positioned in an opening part fits in the space in an opening part as much as possible.

  In addition, a light-emitting device can be formed as shown in FIGS. In addition, it demonstrates using two sectional drawings similarly to 2nd and 3rd embodiment, the same code | symbol is shown about the structure similar to what was already demonstrated, and the description is abbreviate | omitted. In the light emitting device 65 shown in FIGS. 18A and 18B, positions corresponding to the pad electrodes 24a, 24b, and 43 are opened, and a protective layer 66 that covers the side surface and the back surface of the first semiconductor substrate 21 is formed. Has been. An electrode connection layer 67 is formed on the pad electrodes 24 a, 24 b, 43 at the opening positions of the protective layer 66. The electrode connection layer 67 is a layer in which, for example, a nickel (Ni) layer and a gold (Au) layer are sequentially laminated, and a lift-off method in which these metals are sequentially sputtered using a resist layer as a mask, and then the resist is removed, or plating Can be formed by law. A conductive terminal 68 made of solder or the like is formed on the pad electrodes 24 a, 24 b, 43 via an electrode connection layer 67. As described above, the insulating film (the second insulating film 27 in the second embodiment) and the wiring layers (the wiring layers 28 and 29 in the second embodiment) are formed on the side surface and the back surface of the first semiconductor substrate 21. Alternatively, the conductive terminal 68 can be formed so as to be adjacent to the side wall of the first semiconductor substrate 21.

  According to such a configuration, the step of forming the insulating film and the wiring layer shown in the light emitting devices of the first to third embodiments is unnecessary. Therefore, the manufacturing process is simplified and the manufacturing cost can be kept low. Further, since the conductive terminal 68 is not formed on the back surface of the first semiconductor substrate 21 but is formed adjacent to the side wall of the first semiconductor substrate 21, the light emitting device can be thinned. Note that the portion of the semiconductor substrate 21 to be etched can be changed as appropriate when the opening 26 is formed. Therefore, it is possible to form the conductive terminal 68 so as to be embedded in the side wall of the first semiconductor substrate 21 and not expose the conductive terminal 68 from the side surface of the light emitting device.

  In the above-described embodiment, the semiconductor substrate is used. However, it is possible to use a substrate made of an insulating material such as glass or quartz instead of the semiconductor. Further, a substrate that is transparent and has a property of transmitting light may be used depending on the application of the apparatus.

  In the second and third embodiments described above, a conductive terminal and a wiring layer for supplying a voltage to the light emitting element and the device element are formed on one substrate (the substrate on which the light emitting element is formed). It was. In the second embodiment, the opening 26 is formed on the first semiconductor substrate 21 side, and then the wiring layers 28 and 29 and the conductive terminal 32 are formed. However, the present invention is not limited to this. Therefore, a wiring layer or a conductive terminal may be formed on the other substrate (the substrate on which the light emitting element is not formed) as necessary.

  In the above-described embodiment, the pad electrodes formed on the two substrates (in the second embodiment, the pad electrodes 24a and 24b and the pad electrode 43) are bonded so as not to overlap. Even if the pad electrodes overlap, it is possible to supply voltage to each pad electrode from both directions by forming openings, wiring layers and conductive terminals on the substrate on which the respective pad electrodes are formed. It is. Moreover, even if both pad electrodes overlap as shown in FIG. 19, the area of either (pad electrode 43 in FIG. 19) is made larger than the other (pad electrodes 24a and 24b in FIG. 19) to overlap. Each pad electrode and the wiring layer can be connected by using a region that is not provided. Thus, the way of supplying voltage to the element can be changed as appropriate.

  In the above embodiment, the BGA type light emitting device having the ball-like conductive terminals (8, 32, 68) has been described. However, the present invention is applied to an LGA (Land Grid Array) type light emitting device. It does not matter. The present invention can be widely applied as a technique for sealing a light emitting element in a small size.

It is sectional drawing explaining the light-emitting device which concerns on the 1st Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is a top view explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is a top view explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is a top view explaining the light-emitting device which concerns on the 2nd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the 3rd Embodiment of this invention, and its manufacturing method. It is a top view explaining the light-emitting device which concerns on the 3rd Embodiment of this invention, and its manufacturing method. It is sectional drawing explaining the light-emitting device which concerns on the example of a change of this invention. It is sectional drawing explaining the light-emitting device which concerns on the example of a change of this invention. It is a top view explaining the light-emitting device which concerns on the example of a change of this invention. It is sectional drawing explaining the conventional light-emitting device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st semiconductor substrate 2 N type semiconductor layer 3 P type semiconductor layer
4a, 4b Pad electrode 5 Insulating film 6 Wiring layer 7 Protective layer
DESCRIPTION OF SYMBOLS 8 Conductive terminal 10 Opening part 11 2nd semiconductor substrate 12 Adhesion layer 13 Notch part 21 1st semiconductor substrate 22 N type semiconductor layer 23 P type semiconductor layer 24a, 24b Pad electrode 25 Adhesion layer 26 Opening part 27 2nd Insulating film 28 Wiring layer 29 Wiring layer 30 Notch 31 Protective layer 32 Conductive terminal 35 Light emitting device 36 Light emitting device 36 Wiring layer 40 Device element 41 Second semiconductor substrate 42 First insulating film 43 Pad electrode 44 Opening 50 Light emitting device 51 P Type semiconductor layer 52 insulating layer 53 conductive layer 54 opening 55 metal layer 56 conductive terminal 60 lens 65 light emitting device 66 protective layer 67 electrode connection layer 68 conductive terminal 100 LED device 101 first lead 102 LED chip 103 bonding wire 104 second Lead 105 Concave surface 106 Transparent resin layer

Claims (18)

A first substrate having a light emitting element formed on the surface;
A second substrate having an opening penetrating from the front surface to the back surface,
The surface side of the first substrate and the surface side of the second substrate face each other and are bonded together through an adhesive layer,
The light-emitting device, wherein the light-emitting element is exposed to the bottom surface of the opening through the adhesive layer while the opening is left open .   The light emitting device according to claim 1, wherein a device element is formed on a surface of the second substrate.   The light emitting apparatus according to claim 2, wherein the device element includes a drive element that controls light emission and extinction of the light emitting element.   A first pad electrode electrically connected to the light emitting element on the surface of the first substrate, and a second electrode electrically connected to the device element on the surface of the second substrate. The light emitting device according to claim 2, further comprising a pad electrode.   The light emitting device according to claim 4, wherein the first pad electrode and the second pad electrode are bonded so as not to overlap each other.   A portion of the adhesive layer from the surface of the first substrate to the second pad electrode is removed, and a conductive material connected to the second pad electrode is formed on the removed portion of the adhesive layer. The light emitting device according to claim 4, wherein the light emitting device is provided.   4. The light emitting device according to claim 1, wherein a side wall in the opening portion is inclined so that an opening diameter thereof increases from a front surface side to a back surface side of the second substrate. . The light emitting element has a plurality of light emitting portions on the surface of the first substrate,
The light-emitting device according to claim 1, wherein the opening is formed at a position corresponding to the plurality of light-emitting portions.   The light emitting device according to claim 8, wherein the light emitting units are formed in a matrix on the surface of the first substrate.   The light emitting device according to claim 4, further comprising a conductive terminal electrically connected to the first or second pad electrode and protruding in a thickness direction of the first or second substrate.   5. The light emitting device according to claim 4, further comprising a wiring layer that is electrically connected to the first or second pad electrode and is formed along a side surface of the first substrate. A first substrate having a light emitting element formed on the surface;
Preparing a second substrate;
Facing the surface side of the first substrate and the surface side of the second substrate, and bonding them together via an adhesive layer;
Before or after the bonding step , a step of forming an opening through the second substrate from the front surface side to the back surface side and exposing the light emitting element through the adhesive layer on the bottom surface ;
A step of cutting the first and second substrates along a predetermined dicing line and dividing them into individual chips , wherein the opening remains open. Method.   13. The method for manufacturing a light emitting device according to claim 12, further comprising a step of forming a device element on the surface of the second substrate. A first pad electrode electrically connected to the light emitting element on the surface of the first substrate;
The method for manufacturing a light-emitting device according to claim 13, further comprising a second pad electrode electrically connected to the device element on a surface of the second substrate.   15. The step of bonding the first substrate and the second substrate is performed so that the first pad electrode and the second pad electrode do not overlap each other. Manufacturing method of light-emitting device. Removing a portion of the first substrate from the back side of the first substrate to expose at least a portion of the first pad electrode;
16. The method of claim 14, further comprising: removing a part of the adhesive layer from the back surface side of the first substrate to expose at least a part of the second pad electrode. The manufacturing method of the light-emitting device of description.   16. The method according to claim 14, further comprising a step of forming a wiring layer electrically connected to the first or second pad electrode along a side surface of the first substrate. Manufacturing method of light-emitting device.   16. The method according to claim 14, further comprising a step of forming a conductive terminal electrically connected to the first or second pad electrode and protruding in a thickness direction of the first or second substrate. The manufacturing method of the light-emitting device as described in any one of.

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