JP5350970B2 - Method for manufacturing light emitting device - Google Patents

Description

  The present invention relates to a method for manufacturing a light emitting device using an LED element, and more particularly to a method for manufacturing a light emitting device that achieves high reliability by an airtight sealing structure using an inorganic material substrate and a glass lid.

  In recent years, light-emitting devices using LED elements have become widespread, and demand for in-vehicle devices, large-sized televisions, notebook PCs, and the like is rapidly expanding. Along with this, demands for long life, high reliability, energy saving, and the like for light emitting devices using LED elements have become strong, and new technology development for realizing this has been desired.

  Various new technological developments have been made to meet the above requirements. For example, in Patent Document 1, a plurality of recesses are formed in an inorganic material substrate, and LED elements are mounted in each recess, and then air-tight with a glass lid. A manufacturing method is described in which a plurality of light emitting devices are produced simultaneously by stopping. As a method of cutting and separating each light emitting device, a groove having a depth of about three-fourths of the plate thickness is formed by dicing from both directions of the inorganic material substrate and the glass lid, and the two grooves are cleaved. Thus, individual light emitting devices are completed by cutting and separating.

  In addition, as a method for processing a glass lid in a display device, Patent Document 2 discloses a method for cutting a glass plate. Etching with hydrofluoric acid is performed on both sides of the glass plate to form a counter groove, and the gap between the opposing grooves is cleaved. A method of cutting and separating is described.

  Furthermore, in Patent Document 3, as a method for producing a glass lid, a hydrofluoric acid resistant film is formed on one surface of a glass plate, and a blast resistant film having an opening for forming a concave portion of the lid is formed on the hydrofluoric acid resistant film. . A method is described in which a recess is formed by blasting with a blast resistant film, and surface finishing is performed by etching in the recess with a hydrofluoric acid resistant film.

JP 2007-184426 A Japanese Patent Laid-Open No. 3-232731 JP 2005-139039 A

  As described above, the manufacturing method of the light emitting device disclosed in Patent Document 1 is a method of cutting and separating the light emitting devices from each other with a depth of about three-quarters of the plate thickness by dicing from both directions of the inorganic material substrate and the glass lid. In this method, a groove is formed, and the two grooves are cleaved and cut and separated. Therefore, in this method, it is necessary to perform dicing twice, which increases the number of processing steps and increases the manufacturing cost, and in the case of a light emitting device, the fact that there is a fractured surface due to cleavage on the side surface of the glass lid is a light emitting shape. It is considered undesirable because of irregular reflection.

  Further, when the glass product dividing method shown in Patent Document 2 is also used in a light emitting device, a broken surface due to cleavage remains on the side surface of the glass lid, and irregular reflection occurs in the light emitting shape, which is not preferable.

  An object of the present invention is to provide a light emitting device in which an LED element is sealed with a glass lid by applying a method for manufacturing a glass lid as shown in cited document 3 and having a good light emission shape and low manufacturing cost.

  The manufacturing method of the present invention for achieving the above object is to manufacture a light emitting device in which an LED element is mounted on an inorganic material substrate, and a glass lid is adhered and sealed around the LED element mounting region on the inorganic material substrate. In the method, the glass lid forms a recess by sandblasting on one surface of the flat glass, and after forming a groove by scribing around the recess on the other surface of the flat glass, by hydrofluoric acid processing The recess and the groove are chamfered, and the position of the groove is cut by dicing from the recess forming surface side.

  According to the above manufacturing method, since chamfering of the recess by sandblasting and the groove by scribing in the glass lid processing can be performed simultaneously by one hydrofluoric acid processing, chipping and cracking at the time of dicing processing of the glass lid are prevented. In addition, the productivity of the glass lid can be improved and the cost can be reduced.

  The inorganic material substrate and the glass lid may be bonded by welding with a metal material.

  After the inorganic material substrate and the glass lid are welded, it may be cut by performing a dicing process from the inorganic material substrate side toward the groove of the glass lid.

  In addition, the manufacturing method of the present invention includes a large-sized substrate forming step in which each pattern is formed on a large-sized inorganic material substrate and then a plurality of light-emitting portions in a state where the LED elements are FC-mounted are aligned, A recess forming step for aligning and forming a plurality of recesses of the glass lid by sandblasting on the surface, a groove forming step for forming grooves by scribing at a cutting position around the recess on the other surface of the large flat glass having the recesses, A large glass cover forming step for forming a large glass cover by chamfering the concave portion and the groove by a hydrofluoric acid process on a large flat glass having recesses and grooves formed thereon, and the large substrate and the large glass cover. Forming a large-sized light-emitting device that is integrated by welding, and dicing the large-sized light-emitting device from the inorganic material substrate side toward the groove position of the large-sized glass lid By engineering, characterized in that it is cut and separated with a cutting and separating step of creating the individual light emitting devices.

  According to the above manufacturing method, mass production of light-emitting devices can be performed by using a large-sized substrate and a large-sized glass lid, and chamfering of a recess by sandblasting and a groove by scribing is performed once in large-sized glass lid processing. Since it can be performed simultaneously by hydrofluoric acid processing, chipping and cracking during the dicing processing of the glass lid can be prevented, the productivity of the glass lid is improved, and the cost can be reduced.

  The light emitting portion in the large-sized substrate forming step is preferably provided with a wavelength conversion layer around the LED element mounting portion.

  As described above, in the manufacturing method of the present invention, the chamfering of the recess by sandblasting and the groove by scribing can be simultaneously performed by one hydrofluoric acid processing in the glass lid processing. Chipping and cracking can be prevented, the productivity of the glass lid is improved, and the cost can be reduced.

It is sectional drawing of the light-emitting device in 1st Embodiment of this invention. It is the elements on larger scale of the glass cover in the light-emitting device shown in FIG. It is process drawing which shows the manufacturing process of the light-emitting device shown in FIG. It is process drawing which shows the process process of the glass cover used for the light-emitting device shown in FIG. It is process drawing which shows the manufacturing process of the light-emitting device shown in FIG. 1, and has shown the cross section of each element. It is a characteristic table | surface which shows the characteristic and combination of the inorganic material board | substrate and glass cover in this invention. It is a perspective view of the lower surface side of the large format flat glass for producing simultaneously the glass cover in 2nd Embodiment of this invention. It is a perspective view of the upper surface side of the large sized flat glass for producing simultaneously the glass cover in 2nd Embodiment of this invention. It is a perspective view of the large format board | substrate for producing several inorganic material board | substrates simultaneously in 2nd Embodiment of this invention. It is a perspective view of the large format light-emitting device in 2nd Embodiment of this invention. It is a perspective view of the light-emitting device which cut | disconnected and separated the large sized light-emitting device shown in FIG.

(First embodiment)
Hereinafter, a method for manufacturing a light emitting device according to an embodiment of the present invention will be described with reference to the drawings. 1 to 5 show a light emitting device and a glass lid according to a first embodiment of the present invention. FIG. 1 is a sectional view of the light emitting device, FIG. 2 is a partially enlarged sectional view of the glass lid shown in FIG. 3 is a process diagram showing a manufacturing process of the light emitting device shown in FIG. 1, FIG. 4 is a process diagram showing a processing process of a glass lid used in the light emitting device shown in FIG. 1, and FIG. 5 is a manufacturing process of the light emitting device shown in FIG. It is sectional drawing of each element which shows.

  FIG. 1 is a cross-sectional view of a light emitting device 10. A wiring pattern 2 a is formed on the upper surface side of the inorganic material substrate 2, and an output electrode 2 b is formed on the back surface. Are connected by a through hole 2c. The LED element 1 is flip-chip mounted (hereinafter abbreviated as FC mounting) on the wiring pattern 2a of the inorganic material substrate 2, and the LED element 1 is surrounded by a resin layer or glass layer mixed with fluorescent particles. The conversion layer 3 is covered. Further, the light emitting device 10 is completed by welding and sealing the glass lid 5 with the welding layer 7 formed around the mounting region of the LED element 1 on the upper surface side of the inorganic material substrate 2. A chamfered portion 5m is formed at the upper corner portion of the glass lid 5 to prevent breakage and chipping of the glass lid at the time of cutting and separating by dicing, which will be described later. FIG.

  Next, the manufacturing process of the light emitting device 10 will be described with reference to FIG. First, in the substrate process, an inorganic material substrate such as AIN (aluminum nitride), Al2O3 (aluminum oxide), Si (silicon) or the like is used as the inorganic material substrate 2, and the LED element 1 is FC mounted on the inorganic material substrate 2. An Au layer is formed as a bonding underlayer for depositing an AuSn electrode and a glass lid 5 as an adhesive layer. As the LED element process, Au bumps for FC mounting on the LED element 1 are formed in advance. In the FC mounting process, FC mounting is performed by eutectic bonding of AuSn under a pressurized condition of 300 ° C. In the wavelength conversion layer coating step, the phosphor cap mixed with the phosphor created by the silicon resin molding or the glass molding created in the phosphor molding step is put on the LED element 1 or the silicon resin mixed with the phosphor is dispenser or The wavelength conversion layer 3 is formed by directly covering the LED element 1 with a squeegee.

  In the glass lid processing step, a concave portion is formed by sandblasting on one surface of the flat glass, and a groove is formed by scribing around the concave portion on the other surface of the flat glass, followed by hydrofluoric acid processing. Chamfering of the recesses and grooves is performed (surfaces roughened by machining, and formed corners are processed smoothly). Further, a glass lid 5 is prepared in which an AuSn layer is formed as a welding base layer around the formed recess, that is, at a position where it is welded to the inorganic material substrate 2. In the glass lid welding process, the base material Au formed on the inorganic material substrate 2 and the base material AuSn formed on the glass lid 5 are bonded to the inorganic material substrate 2 by eutectic bonding of AuSn under a pressure condition of 300 ° C. A glass lid 5 is welded. In addition, this glass lid welding process was performed in vacuum or in an inert gas, whereby the sealed case was made in a vacuum or an inert gas atmosphere, and the LED element 1 and the organic resin silicon resin were formed. Deterioration of the wavelength conversion layer 3 can be prevented. Finally, the electrical characteristics and chromaticity of the completed light emitting device 10 are measured in the characteristic measurement step, and ranking is performed according to the result.

  Next, the manufacturing process of the glass lid 5 will be described with reference to FIG. First, in step A, a mask 15 having an opening 15a corresponding to the concave portion 5a of the glass lid 5 is attached to one surface of the flat glass 50, and around the position where the concave portion 5a is formed on the other surface of the flat glass 50. The groove 5b is formed at the cutting position by scribing. Next, in step B, the sand particles 25 are jetted at a high pressure to form the recesses 5a. In addition, as for the internal shape of the recessed part 5a formed by the injection | pouring of the sand particle 25, a roundness is formed in a corner and a satin pattern is formed in the whole inner surface. As the mask at this time, a resin resist or a metal mask is used, and the shape of the recess 5a can be arbitrarily formed by adjusting the sand particle size, the spraying speed, and the spraying time. In addition, a plurality of recesses 5a can be simultaneously formed on a single large flat glass 50 using a mask 15 having openings 15a corresponding to the plurality of recesses 5a (in this embodiment, two recesses are simultaneously formed). Is shown).

  Next, hydrofluoric acid processing (etching) is performed in step C. As a result of the hydrofluoric acid processing, the inside of the concave portion 5a is improved in the permeability of the surface roughened by the sand blast processing, and the generation of cracks and chips due to processing impacts is prevented. Further, the inner surface of the groove 5b is chamfered into a gentle surface shape by roughening the surface by scribing as shown in the figure. That is, a feature of the present invention is that chamfering can be simultaneously performed by one hydrofluoric acid processing on the concave portions 5a and the grooves 5b having a rough surface shape by sandblasting and scribing.

  Next, in step D, each glass lid 5 is separated by cutting by a dicing process using a diamond blade or the like. In this dicing process, when cutting from the surface side where the recess 5a is formed toward the center of the groove 5b, the chamfered portion by the groove is formed on the end surface side of the cutting, so that chipping or cracking of the glass end surface is caused during the dicing process. Does not occur. Prior to the dicing process, the glass cover 5 is completed by forming the AuSn welding base layer 5d on the bonding surface 5c around the recess 5a.

  In this embodiment, the formation of the welding base layer 5d is performed in the step D. However, the present invention is not limited to this. For example, in the first step A, the welding base layer 5d is formed on the entire surface of the flat glass recess 5a. Then, a mask 15 may be formed on the welded underlayer 5d.

Next, a method for manufacturing the light emitting device in the present embodiment will be described.
FIG. 5 also shows a manufacturing process of the light emitting device 10 and shows a cross section of each element. That is, in the substrate process A, an Au layer which is a welding base layer 2d for welding the wiring pattern 2a, the through hole 2c, the output electrode 2b, and the glass lid 5 is formed on the inorganic material substrate 2. In the FC mounting process B, the LED element 1 is FC mounted on the wiring pattern 2 a of the inorganic material substrate 2. In the wavelength conversion layer coating step C, the LED element 1 is covered with a phosphor cap formed by silicon resin molding as the wavelength conversion layer 3. In the glass lid welding step D, AuSn is formed by the AuSn welding ground layer 5d formed on the bonding surface 5c of the glass lid 5 created in FIG. 4 and the Au welding ground layer 2d formed on the inorganic material substrate 2. By this eutectic bonding, the weld layer 7 is formed, and the light emitting device 10 is completed. As described above, the reliability of the hermetic sealing is further increased by performing the glass lid welding step D in a vacuum or in an inert gas atmosphere.

  Next, the combination of the inorganic material substrate 2 and the glass lid 5 will be described. FIG. 6 is a characteristic table showing the characteristics and combinations of the inorganic material substrate 2 and the glass lid 5. Table 1 shows three types of the inorganic material substrate 2, and Table 3 shows three types of the glass lid 5. And the arrow provided between Table 2 has shown the combination. That is, Table 1 shows thermal conductivity and linear expansion coefficient for three kinds of substrate materials of the inorganic material substrate 2: AIN (aluminum nitride), Si (silicon), and Al2O3 (aluminum oxide). As the glass material of the glass lid 5, linear expansion coefficients are shown for three types of borosilicate glass (1), borosilicate glass (2), and borosilicate crown glass.

  Focusing on the linear expansion coefficient in Tables 1 and 2, the substrate material of the inorganic substrate 2 is AIN of 44 [× 10 −7 / ° C.], Si of 30 [× 10 −7 / ° C.], and Al 2 O 3 of 74 [× 10-7 / ° C], whereas borosilicate glass (1), which is a glass material of the glass lid 5, is 47 [× 10-7 / ° C], and borosilicate glass (2) is 33 [× 10-7 / ° C]. [° C.] and borosilicate crown glass is 74 [× 10 −7 / ° C.]. Looking at the relationship between these three types of materials, as indicated by arrows, AIN, which is the substrate material of the inorganic material substrate 2, is a glass material for the glass lid with respect to a linear expansion coefficient of 44 [× 10−7 / ° C.]. The borosilicate glass (1) shows an approximate value of 47 [× 10 −7 / ° C.], and the linear expansion coefficient of the substrate material Si is 30 [× 10 −7 / ° C.], whereas glass The material borosilicate glass (2) approximates 33 [× 10 −7 / ° C.], and similarly the linear expansion coefficient of the substrate material Al 2 O 3 is 74 [× 10 −7 / ° C.], whereas the glass material The linear expansion coefficient of borosilicate crown glass is approximately 74 [× 10 −7 / ° C.].

  As described with reference to FIG. 3, when the AuSn eutectic bonding is performed between the inorganic material substrate 2 and the glass lid 5, since the temperature becomes 300 ° C., the linear expansion coefficients of the inorganic material substrate 2 and the glass lid 5 are different. Therefore, it is necessary to select a material that approximates the linear expansion coefficient of the inorganic material substrate 2 and the glass lid 5 as much as possible. In this sense, it can be seen that combinations of materials indicated by arrows as shown in Tables 1 and 2 are desirable. In addition, as a glass material shown in Table 2, commercially available borosilicate glass (1) includes “VIDREX (registered trademark)” (trade name of Beatrex Co., Ltd.), and borosilicate glass (2). "Pyrex (registered trademark)" (a product name of Corning) has this characteristic.

(Second Embodiment)
Next, a manufacturing method and a structure of a light emitting device by the collective substrate method in the second embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a perspective view of a large flat glass 50L for simultaneously producing a plurality of glass lids 5 shown in FIG. 4, and a recess 5a is formed on the lower surface side 50a, which is one surface of the large flat glass 50L, by sandblasting. A plurality are arranged. FIG. 8 is a perspective view showing the upper surface side 50b, which is the other surface of the large flat glass 50L shown in FIG. 7, and a plurality of cutting positions around the recessed portions 5a formed by arranging a plurality of lines are indicated by a scribe process. The grooves 5b are formed vertically and horizontally. Further, the large flat glass 50L is hydrofluoric acid processed, so that the recess 5a by sandblasting and the groove 5b by scribing are chamfered to form a smooth inner surface shape.

  FIG. 9 is a perspective view of a large-sized substrate 20 for simultaneously producing a plurality of inorganic material substrates 2 shown in FIG. 5, and in the state shown in FIG. 5C, that is, after forming each pattern on the inorganic material substrate 2, This corresponds to a state in which a plurality of light emitting portions 1a in which the element 1 is FC-mounted and the wavelength conversion layer 3 is provided are aligned. The plurality of light emitting portions 1a formed in alignment in FIG. 9 have the same arrangement position and the same number as the concave portions 5a of the glass lid 5 formed in alignment in FIG.

  FIG. 10 is a perspective view of the large format light emitting device 10L, in which a large format flat glass 50L is laminated and integrated on the upper surface side of the large format substrate 20 in the state shown in FIG. Therefore, on the upper surface side 50b of the large flat glass 50L, the bottom portion of the concave portion 5a in the glass lid 5, that is, the light emission window portion is indicated by a dotted line. The completed large-sized light emitting device 10L is cut by dicing using a diamond blade or the like along the X and Y cutting lines from the lower surface side of the large-sized substrate 20 to complete each light emitting device 10. In the dicing process, cutting is performed toward the center of the groove 5b provided on the upper surface side 50b of the large flat glass 50L.

  FIG. 11 is a perspective view of the completed light-emitting device 10. Each corner on the upper surface side of the glass lid 5 is formed by welding and integrating the glass lid 5 on the inorganic material substrate 2 and dicing from the lower surface side of the inorganic material substrate 2. A chamfered portion 5m formed by the groove 5b is formed in the portion, and the presence of the chamfered portion 5m prevents the occurrence of cracking and chipping against an impact at the time of cutting and an impact at the time of handling. As a light emitting operation, the LED element 1 emits light through the wavelength conversion layer 3 from the light emitting window portion at the bottom of the concave portion 5 a in the glass lid 5.

  As described above, in the method for manufacturing a light emitting device by the collective substrate method, the large-sized flat glass 50L is used to constitute the glass lid 5, and a plurality of concave portions 5a and a plurality of grooves 5b are formed on the large-sized flat glass 50L by sandblasting. Formed by processing and scribing, chamfering the rough processed surface of the recess 5a and groove 5b by this processing by one hydrofluoric acid processing, and welding and integrating the large flat glass 50L and the large substrate 20, By cutting and separating by dicing, the light-emitting device 10 in which the corner portion of the glass lid 5 is chamfered can be easily mass-produced.

  As described above, for the light emitting device in the present invention, the LED element 1 and the phosphor used in the embodiment can be a combination of a blue LED element and a YAG phosphor, or a combination of a near ultraviolet LED element and an RGB phosphor, Furthermore, the present invention can also be applied to the case of a single LED element having no phosphor. The glass lid in the present invention is also effective for sealing elements other than LED elements.

DESCRIPTION OF SYMBOLS 1 LED element 1a Light emission part 2 Inorganic material board | substrate 2a Wiring pattern 2b Output electrode 2c Through-hole 2d Welding base layer 3 Wavelength conversion layer 5 Glass cover 5a Recess 5b Groove 5c Joining surface 5d Welding base layer 5m Chamfer 7 Welding layer 10 Light emitting device 10L Large Format Light Emitting Device 15 Mask 15a Opening 20 Large Format Substrate 25 Sand Particle 50 Flat Glass 50a Lower Side 50b Upper Side 50L Large Format Flat Glass

Claims (5)

  In the method of manufacturing a light emitting device, in which an LED element is mounted on an inorganic material substrate, and a glass lid is welded and sealed around the LED element mounting region on the inorganic material substrate, the glass lid is formed on one surface of the flat glass. A recess is formed by sandblasting, and a groove is formed by scribing at a cutting position around the recess on the other surface of the flat glass, and then the recess and the groove are chamfered by hydrofluoric acid processing to form the recess. A method for manufacturing a light emitting device, comprising cutting the position of the groove by dicing from a surface side.   The method for manufacturing a light emitting device according to claim 1, wherein the inorganic material substrate and the glass lid are bonded by welding with a metal material.   3. The method for manufacturing a light emitting device according to claim 2, wherein the inorganic material substrate and the glass lid are welded and then cut by dicing from the inorganic material substrate side toward the groove of the glass lid. After forming each pattern on a large-sized inorganic material substrate, a large-sized substrate forming step in which a plurality of light emitting portions with LED elements mounted in FC are aligned and formed,
A recess forming step in which a plurality of recesses of the glass lid are aligned and formed on one surface by sandblasting on a large flat glass, and a scribing is performed at a cutting position around the recess on the other surface of the large flat glass on which the recesses are formed. A large-sized glass lid is formed by a groove forming step of forming grooves by processing, and a hydrofluoric acid processing step of chamfering the recesses and the grooves by hydrofluoric acid processing of the large flat glass having the concave portions and the grooves formed therein. A glass lid forming step;
A large-sized light emitting device forming step of welding and integrating the large-sized substrate and the large-sized glass lid;
A cutting and separating step of creating individual light emitting devices by cutting and separating by dicing the large light emitting device from the inorganic material substrate side toward the groove position of the large size glass lid;
A method for manufacturing a light emitting device. The light emitting device manufacturing method according to claim 4, wherein the light emitting portion in the large format substrate forming step further includes a wavelength conversion layer around the LED element mounting portion.

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