JP4238693B2 - Optical device - Google Patents

Description

  The present invention relates to an optical device, and more particularly to an optical device in which an LED element is sealed with a glass material that has excellent heat resistance and long-term reliability with respect to higher output of a light emitting element.

  In recent years, high-power LEDs (Light-Emitting Diodes) have been developed, and a high-power type of several watts has already been commercialized. LEDs are characterized by low heat generation, but high power (high brightness) type LED elements generate a large amount of current, and therefore generate heat that cannot be ignored.

  Conventionally, the LED element does not have a high output type, and therefore, no special heat dissipation measures are taken, and it is only necessary to dissipate heat from the lead portion. And when heat_generation | fever becomes a problem, measures, such as attaching a copper heat sink to the lower surface of the member which mounts the LED element, were taken (for example, refer patent document 1).

  In the LED package of Patent Document 1, a slag to be a heat sink is insert-molded and inserted into a lead frame having a molded plastic material. A light emitting diode die (LED die) is directly or indirectly attached to the slag via a sub-base having excellent thermal conductivity, and the LED is mounted on the LED die. The LED and light emitting diode die and the lead frame are connected by wires. The LED is covered with an optically transparent lens and encapsulant.

With this configuration, the LED die is thermally bonded to the slug, so that the LED die is maintained at a lower junction temperature than the conventional package. By lowering the temperature, the LED die is not subjected to large thermal stress, and the reliability and good characteristics in high power operation can be maintained.
Japanese Patent Laid-Open No. 2000-150967 ([0008], FIG. 2)

However, the conventional light emitting device has the following problems.
(1) Since the sealing member is not directly bonded to or held by the holding member, a secondary holding material (for example, embedded plastic material) is required, increasing the number of parts and realizing a compact package. Can not do it.
(2) Moreover, since the secondary holding material is formed of resin, it does not have heat resistance corresponding to a lead-free reflow furnace.

  On the other hand, there is a glass material as a material excellent in durability and heat resistance. However, when sealing with glass, heat resistance to withstand heat processing is required. Further, since the glass material is processed at a high temperature, depending on the member to be bonded, interfacial peeling is likely to occur due to a difference in thermal expansion and contraction during sealing.

  Accordingly, an object of the present invention is to provide an optical device that has heat resistance and light resistance and is not destroyed by thermal expansion and contraction.

In order to achieve the above object, the present invention mounts an optical element and the optical element, and has a thermal expansion coefficient equivalent to that of the optical element, and an area of the surface on which the optical element is mounted is the optical element. and 2 times or less of the element mount portion of provided with a hole for fitting the element mount portion, and a large consisting holding member of the element mounting portion by Rinetsu expansion rate, wavelength of interest as well as sealing the optical element have a light-transmitting property with respect to, and a sealing member formed of a glass material, the element mount portion, the hole of the holding member surface for mounting the optical element on the sealing member side The holding member and the sealing member are joined to each other, and the difference in thermal expansion coefficient between the holding member and the sealing member is 15 with respect to the thermal expansion coefficient of the holding member. An optical device characterized by being within% is provided.

The optical element is plural,
The element mount portion may be provided for each of the plurality of optical elements and may be arranged in an island shape.

Before Kifu stop member, the second sealing for sealing the first sealing member for sealing the optical element and the periphery thereof, the exposed surface of the upper surface of the first sealing member and the retaining member With members,
It said first sealing member, it is preferable to have a thermal expansion coefficient intermediate between the second sealing member and the element mounting portion.

It is preferable that the element mount portion is formed in a convex cross section that can be engaged with the holding member.

  The holding member may be made of a ceramic material.

The holding member may be formed of a glass-containing Al ₂ O ₃ material.

  The holding member may be a multilayer board in which wiring patterns are laminated in a cross section.

  The optical element may be a light emitting element.

  The optical element may be flip-chip bonded.

  The optical element is a face-up type light emitting element, and may be covered with a heat resistant material together with a wire electrically connected to the light emitting element.

The element mount portion may have a heat radiating portion on the bottom surface.

  According to the optical device of the present invention, the thermal expansion coefficients of the optical element and the element mount member are made equal, and the stress due to the temperature difference at the location of the optical element and the element mount member is reduced. In addition, stress damage to the optical element due to thermal expansion and contraction caused by the atmospheric temperature of the reflow furnace or the heat generated by use was not caused. Further, the holding member and the sealing member have the same thermal expansion coefficient, and the element mounting member is inserted and held in the through hole of the holding member, and the surface of the element mounting member for mounting the LED element is substantially the same. Due to the LED element size, the stress caused by the temperature difference between the high temperature state and the normal temperature state during glass processing is kept low between the holding member and the sealing member with a wide contact area and a long linear distance, and peeling and cracking are not caused. When it does not occur, glass sealing is possible, and light resistance and heat resistance with respect to light of a target wavelength can be secured and a compact package can be realized.

  1A and 1B are diagrams showing a configuration of an optical device according to a first embodiment of the present invention, where FIG. 1A is a plan view and FIG. 1B is a cross-sectional view taken along line AA. The light emitting device 1 includes an LED element 11, an element mount portion 12 on which the LED element 11 is mounted, a holding member 13 for mounting the element mount portion 12 on a through-hole portion, an element mount portion 12 and its surroundings. A sealing member 14 (glass sealing portion) that seals the holding member 13 is provided.

The LED element 11 is a high output type made of a material such as GaN or AlInGaP (thermal expansion coefficient 4-6 × 10 ⁻⁶ / ° C.), and the lower surface is connected to the wiring layer of the holding member 12. The flip chip type is provided with the electrode 11a (or solder bump) to be used.

The element mount portion 12 is made of a material having a thermal expansion coefficient equivalent to that of the LED element 11, for example, Al ₂ O ₃ (aluminum oxide: thermal expansion coefficient 7 × 10 ⁻⁶ / ° C.). The area of the upper surface of the element mount portion 12 (the portion exposed from the holding member 13) is not more than twice that of the LED element 11, and preferably about the same. The element mount portion 12 is formed with wiring layers 12a and 12b extending from the upper surface to the side surface, and is connected to the electrode 11a of the LED element 11. Further, the holding member 12 can incorporate a zener diode or the like for preventing element destruction as required.

The holding member 13 is made of ceramic, glass-containing Al ₂ O ₃ (thermal expansion coefficient 13 × 10 ⁻⁶ / ° C.), and a through-hole for inserting the element mount 12 is formed at a predetermined position. ing. Wiring layers 13 a and 13 b connected to the wiring layers 12 a and 12 b are formed in the through hole over the upper surface of the holding member 13, the side surface in the through hole, and the lower surface of the holding member 13.

The sealing member 14 has a low coefficient of thermal expansion that is equivalent to that of the holding member 13 (the difference between the thermal expansion coefficients of the holding member 13 and the sealing member 14 with respect to the thermal expansion coefficient of the holding member 13 is within 15%). Melting glass (thermal expansion coefficient 11 × 10 ⁻⁶ / ° C.) is used. The low melting point glass has a larger coefficient of thermal expansion than general glass. Moreover, if low melting glass is not used, the LED element 11 is thermally damaged during processing.

  Next, the manufacturing process of the light emitting device 1 will be described.

  It is assumed that wiring layers 12 a and 12 b are formed in advance in the element mount portion 12 by a separate process, and an electrode 11 a is formed in advance in the LED element 11. First, a through hole in which the element mount 12 can be fitted is formed at a predetermined position of the holding member 13, and then the wiring layers 13a and 13b are formed through the through hole. Next, the element mount portion 12 is inserted into the through hole of the holding member 13. At this time, the wiring layers 12a and 12b and the wiring layers 13a and 13b face each other and are inserted through a brazing material (Au—Si system). In this state, the element mounting portion 12 is fixed to the holding member 13 by placing in a temperature atmosphere of 400 ° C. or higher and melting the brazing material between the wiring layers. The order in which the LED element 11 is mounted on the holding member 13 after the holding member 13 has already been mounted on the element mounting portion 12 may be used.

  Next, the polarities of the wiring layers 12a, 12b and the electrode 11a are matched, and the LED element 11 is mounted on the upper surface of the element mount portion 12 via an Au bump, thereby completing the connection and fixing of the LED element 11. . Next, the sealing member 14 is sealed so as to cover the upper surfaces of the LED element 11 and the surrounding holding member 13. In FIG. 1, the sealing member 14 is provided so as to have a uniform thickness, but the sealing may be performed so that a lens is formed on the LED element 11.

  For example, if the wiring layer 13a is connected to the anode side of the LED element 11, the plus side of a DC power supply (not shown) is connected to the wiring layer 13a, and the minus side is connected to the wiring layer 13b. Along with the power supply, current flows through a route of the wiring layer 13a → the wiring layer 12a → the LED element 11 → the wiring layer 12b → the wiring layer 13b, and the LED element 11 emits light. The light emitted from the upper surface of the LED element 11 passes through the sealing member 14 and exits to the outside.

According to the first embodiment described above, the following effects are obtained.
(1) Since the sealing member 14 is made of glass having translucency with respect to the target wavelength, deterioration due to light and heat is extremely small compared to the sealing resin, and stable light emission characteristics over a long period of time. can get.
(2) Since the thermal expansion coefficients of the LED element 11 and the element mounting portion 12 are made equal, the LED element is caused by a temperature difference between a high temperature state and a normal temperature state during glass processing or a temperature difference caused by a blinking operation of the LED element 11. 11 and the element mounting portion 12 can be reduced in stress and excellent in reliability.
(3) The thermal expansion coefficients of the holding member 13 and the sealing member 14 are made equal to each other, the element mount portion 12 is fitted and held in the through hole of the holding member 13, and the LED element 11 of the element mount portion 12 is held. Since the surface on which the lens is mounted is approximately the size of the LED element, the stress caused by the temperature difference between the high temperature state and the normal temperature state during glass processing is applied between the holding member 13 and the sealing member 14 having a wide contact area and a long linear distance. Is kept low and does not cause peeling or cracking. In addition, the LED element 11 and the element mounting portion 12 that have a low thermal expansion coefficient with respect to the sealing member 14 are as small as possible (the size of the LED element 11), and a compressive force is applied during cooling during glass processing. Therefore, no peeling or cracking occurs. Thus, a glass-sealed LED can be realized.
(4) Since the holding member 13 and the sealing member 14 are bonded to each other by a chemical reaction by using glass for the sealing member 14, the interfacial peeling is performed as compared with the case where a resin is used as the sealing member 14. Is less likely to occur. Further, a compact package can be realized, and a sufficient adhesive force can be obtained even if the adhesive area between the holding member 13 and the sealing member 14 is small.
(5) The sealing member 14 can be provided on one side of the holding member 13 and the wiring layers 13a and 13b as external terminals can be provided on the other side, so that a compact surface mount optical device can be obtained.
(6) The constituent members are all heat-resistant members, and the stress due to temperature changes is also kept low, so that they can withstand the reflow furnace treatment of lead-free solder.

  The glass used for the sealing member 14 may be a hybrid glass formed by combining an organic material and an inorganic material. Although such a material can also achieve a low melting point as well as heat resistance and light resistance, it has the same thermal expansion coefficient as that of the low melting point glass described above.

In addition to the Al ₂ O ₃ , the element mount portion 12 can be formed of AlN or silicon.

  Further, although it has been described that a through hole for fitting the element mount portion 12 into the holding member 13 is formed, if the exposed area of the element mount portion 12 on the sealing member side is not large, the through hole is not necessarily required. Absent.

  FIG. 2 is a partial cross-sectional view showing a modification of the holding member in the optical device according to the first embodiment. Here, only the main part centering on the LED element mounting part is not shown, and the sealing member and the like are not shown. In the light emitting device 1 of FIG. 1, the number of LED elements to be mounted is one, but the luminance is increased by increasing the number of light emission in three colors of R, G, B, or the same color, or the color rendering property is improved. Depending on the purpose, a plurality of LED elements can be provided.

  In this case, as shown in FIG. 2, the element mounting portion 21 of the light emitting device 20 increases the area of the uppermost mounting portion according to the number of LED elements to be mounted. Here, it is assumed that three LED elements 22a, 22b, and 22c are mounted on the element mounting portion 21. The element mount portion 21 is different only in size, and the material used is the same as that of the element mount portion 12. Also in this case, it is preferable in the above-described stress relaxation that the area of the mounting portion on the uppermost surface of the element mounting portion 21 is set to a minimum area where the three LED elements 22a, 22b, and 22c can be mounted.

  In the light emitting device 20 shown in FIG. 2, the LED elements 22a, 22b, and 22c are arranged on the same plane at equal intervals. The LED elements 22a, 22b, and 22c may be mounted separately for each of the three colors (R, G, and B), even if all of them have the same emission color. In addition to the wiring layers 12a and 12b described above, the element mount portion 21 is provided with an electrode 21a connected to the LED element 22b and electrodes 21b and 21c connected to the other electrode of the LED elements 22a and 22c on the upper surface. Yes. The electrodes 21a, 21b, and 21c are connected to each other between anodes or cathodes through through holes in the element mount 21 or wiring layers (not shown) provided on the upper surface.

  According to such a configuration, even when a plurality of LED elements 22a, 22b, and 22c are mounted, stress based on thermal expansion and contraction between the holding member 13 and the sealing member (not shown) is suppressed, and the LED element 11 and the light emitting device with excellent reliability by reducing the stress based on thermal expansion and contraction at the element mounting portion 12.

3A and 3B are diagrams showing the configuration of the optical device according to the second embodiment, where FIG. 3A is a cross-sectional view, and FIG. 3B is a schematic plan view showing the arrangement of solder layers and metal leads. The second embodiment is basically the same as the first embodiment, except that the material and shape of the element mounting portion and the holding member 33 are a multilayer substrate, and a circuit pattern is formed in the substrate. And the joint between the holding member 33 and the metal base portion 32. That is, the light emitting device 30 is made of AlN (aluminum nitride: coefficient of thermal expansion: 5 × 10 ⁻⁶ / ° C.) having a high thermal conductivity of 180 W · m ⁻¹ · k ^{−1 so} that the lower side has a large area. The element mounting part 31 having a convex cross section formed with a step is formed so that the area of the joint part with the metal base part 32 is widened. In addition, the upper surface of the metal base portion 32 is processed to be flat so that a joint surface is formed between the metal base portion 32 and the holding member 33.

  The light emitting device 30 includes metal leads 34a and 34b instead of the wiring layers 13a and 13b. Recesses 33d and 33e are formed in the holding member 33 so that the metal leads 34a and 34b do not contact the metal base portion 32, and the tips of the metal leads 34a and 34b are connected to the recesses 33d and 33e. Electrodes 33a and 33b are provided on the lower surfaces of the recesses 33d and 33e for connection to the metal leads 34a and 34b. Instead of the wiring layers 13a and 13b, the element mounting portion 31 and the holding member 33 are formed with wiring layers or through holes inside, and a connection path from the electrode 11a of the LED element 11 to the electrodes 33a and 33b is formed. I am doing so.

  A metal pattern that is not used for electrical connection is formed on a portion of the element mount portion 31 that contacts the metal base portion 32, and a solder layer 31a soldered to the metal base portion 32 is formed. Therefore, the heat dissipation to the metal base part 32 can be improved. In addition, a solder layer 33 c is formed on the holding member 33 at a portion in contact with the metal base portion 32. Since the solder layer 33 c is formed in a “B” shape, the LED element 11 and the element are formed by the sealing member 35, the holding member 33, and the metal base portion 32 by the contact surface between the holding member 33 and the metal base portion 32. The mount part 31 can be sealed.

  The sealing member 35 provided so as to cover a predetermined range of the LED element 11 and the holding member 33 is the same material as the sealing member 14 and has the same thermal conductivity, and has the same shape as the sealing member 14. Sealed.

  The manufacturing procedure of the light-emitting device 30 is the same as that of the light-emitting device 1 of the first embodiment except that the metal leads 34a and 34b are attached. The metal leads 34 a and 34 b are positioned with the whole turned upside down before the metal base portion 32 is attached, and then the metal base portion 32 is positioned on the element mount portion 31 and the holding member 33. While maintaining this state, it is carried into a reflow furnace, and the metal leads 34a, 34b and the metal base portion 32 are fixed to the main body side by solder welding.

  Energization of the light emitting device 30 is the same as that of the light emitting device 10 of the first embodiment, except that the metal leads 34a and 34b are replaced with the wiring layers 13a and 13b of FIG.

  According to the second embodiment described above, in addition to the preferable effects of the first embodiment, the element mount portion 31 has high thermal conductivity, and the surface on which the LED element 11 is mounted is equivalent to the LED element 11. However, since the lower side is widened and the heat transfer path is wide, the heat generated by the LED element 11 is easily transmitted to the metal base portion 32, and the temperature rise when the LED element 11 is lit is suppressed to a low level. Can be increased. Furthermore, the LED element 11 and the element mount part 31 are sealed by the sealing member 35, the holding member 33, and the metal base part 32, and do not receive intrusion of moisture or the like. In addition, an electric terminal area for electrical connection can be secured, and the heights of the element mount portion 31 and the holding member 33 can be easily and accurately matched. In addition, since the holding member 33 is formed of a multilayer substrate, it is possible to reduce restrictions on joining of the metal leads 34a and 34b.

Incidentally, the element mounting part 31 has been described as using AlN thermal conductivity 180W · m ^-1 · k ^-1, thermal conductivity is a sufficient 100W · m ^-1 · k ^-1 or more effect As long as the coefficient of thermal expansion is equivalent to that of the LED element 11, a material other than AlN may be used.

  4A and 4B are diagrams showing a modification of the holding member 33 in the second embodiment. FIG. 4A is a configuration in which a reflective film is provided on the surface of the holding member, and FIG. 4B is a reflection in the concave portion of the holding member. It is the structure which provided the film | membrane. In the holding member 33 in FIG. 3, the upper surface is left as it is, but a reflection film is provided in the vicinity of the LED element 11 to increase the reflection efficiency of light emitted from the LED element 11.

  4A shows a configuration in which a reflective film 33f is provided around the upper portion of the through hole 41. FIG. 4B shows a mortar-shaped recess 33g formed on the upper portion of the through hole 41, and a reflective film on the inner surface thereof. 33h is provided. The reflective films 33f and 33h can be provided by white or silver surface treatment in addition to mirror finishing by silver vapor deposition, silver plating, or the like.

  In FIG. 4A, the thickness (height) of the holding member 33 and the element mounting portion 31 shown in FIG. 3 is increased, but the height of the element mounting portion 31 is left as in FIG. Only 33 may be thinned.

  According to such a configuration, a degree of freedom can be given to the design of the element mount portion 31 and the holding member 33 in addition to the preferable effect of the second embodiment.

  Although only two examples are shown in FIG. 4, for example, a configuration in which a dedicated reflecting mirror is disposed on the upper surface of the holding member 33 so as to surround the LED element 11 may be employed. Moreover, semicircular unevenness | corrugation may be formed in the recessed part 33g, and a diamond-cut polyhedral shape may be given.

  5A and 5B are diagrams showing a configuration of an optical device according to the third embodiment, in which FIG. 5A is a plan view and FIG. 5B is a sectional view taken along line BB in FIG. The light emitting device 20 of FIG. 2 has a configuration in which a plurality of LED elements are mounted on one element mounting portion. However, the light emitting device 50 in the third embodiment prepares an element mounting portion for each LED element. There are structural differences.

  The light emitting device 50 includes one metal base portion 51 and 16 element mount portions 52a, 52b, 52c, 52d, 52e, 52f, 52g, 52h, 52i, which are mounted on the metal base portion 51 at predetermined intervals. 52j, 52k, 52l, 52m, 52n, 52o, and 52p (in FIG. 5, only 16 of 52e, 52f, 52g, and 52h are shown) and provided corresponding to the element mounting portions 52a to 52p. A holding member 53 in which the element mounts 52a to 52p are inserted into the through holes, and 16 LED elements 54a, 54b, 54c, 54d, 54e, 54f, and 54g mounted on the upper surfaces of the element mounts 52a to 52p, respectively. , 54h, 54i, 54j, 54k, 54l, 54m, 54n, 54o, 54p, and the holding member 53 and the LED elements 54a to 54p are covered. It is constituted by a sealing member 55 to be sealed to. In addition, in FIG. 5, although the element mount part and the LED element were each 16 pieces, it can be made into arbitrary numbers according to the request | requirement etc. of a customer.

  The element mount parts 52a to 52p, the holding member 53 (multilayer substrate), the LED elements 54a to 54p, and the sealing member 55 are, for example, the element mount part 12, the holding member 13, and the sealing member in the second embodiment. 14 and the same material and characteristics (thermal expansion coefficient, etc.) are used. A copper foil layer is provided on the lower surfaces (surfaces on the metal base portion 51 side) of the element mount portions 52a to 52p and the holding member 53, and are used for joining to the metal base portion. Here, the element mount portions 52a to 52p are used. The copper foil layers in the 52p and the holding member 53 are combined into a copper foil layer 58.

  The LED elements 54a to 54p are an LED element group that is grouped corresponding to three colors of R, G, and B, and an LED element group that is grouped into a plurality of the same color (for example, blue). Specifically, the 16 LED elements are composed of a first group composed of 54a to 54d, a second group composed of 54e to 54h, a third group composed of 54i to 54l, and 54m to 54p. The fourth group is divided into four groups, and each of the four LED elements is connected in series with the same polarity. One pole (for example, anode) of the four groups is commonly connected by a wiring (not shown) formed in the element mount portions 52a to 52p and the holding member 53, and is connected to the terminal 56e.

  The other poles (for example, cathodes) of the first to fourth groups are individually connected to terminals 56a to 56d, and one ends of resistors R1 to R4 for current limiting are connected to the terminals 56a to 56d. The other ends of R1 to R4 are connected to power supply terminals 57a to 57d. The resistors R1 to R4 are not built in the element mounts 52a to 52p and the holding member 53, but are externally attached. For example, when a DC power source having a predetermined voltage is connected between the terminal 57a and the terminal 56e, four LED elements 54a to 54d emit light at the same time, and a power source is connected between the terminals 57a and 57d and the terminal 56e. LED elements 54a to 54d and 54m to 54p emit light simultaneously.

According to the above-described third embodiment, the following effects can be obtained.
(1) Since the light-emitting device 50 is provided with an element mount for each LED element, the LED elements 54a to 54p are lit even if the number of LED elements used increases or decreases in addition to the preferable effect of the second embodiment. The temperature rise at the time can be kept low. In addition, it is not necessary to design a new element mount portion each time the number of LED elements is changed, thereby improving design flexibility and shortening the delivery time for customer orders.
(2) Since the thermal expansion coefficient of the sealing member 55 is formed to be the same as that of the holding member 53 and the element mount portions 52a to 52p are arranged in an island shape on the holding member 53, heat is generated from the element mount portions 52a to 52p. With respect to the thermal expansion and contraction of the sealing member 55 and the holding member 53 having a large expansion coefficient, each element mounting portion moves in accordance with the expansion and contraction. This is equivalent to the case of one LED element, no stress is generated between the LED element and the element mounting portion, and no interfacial peeling between the sealing member 55 and the holding member 53 occurs.
(3) Since the heat generated by the LED elements 54a to 54p is transferred to the holding member 53 through the element mounts 52a to 52p and radiated, the heat efficiency is improved, and the LED elements 54a to 54p are of high output type. However, the LED elements 54a to 54p, the element mount parts 52a to 52p, the holding member 53, the glass sealing part 55 and the like are not damaged, and the heat resistance, weather resistance, and durability are improved.
(4) By using the holding member 53 made of a multilayer substrate, an arbitrary circuit pattern can be formed without hindering heat dissipation.

6A and 6B are diagrams showing a configuration of an optical device according to the fourth embodiment, in which FIG. 6A is a plan view and FIG. 6B is a cross-sectional view taken along the line C-C in FIG. The light emitting device 60 according to the fourth embodiment has the same basic configuration as the light emitting device 50 of FIG. The difference is that a metal reflector serving as a second radiator and a reflector is provided on the holding member 53 made of a glass-containing Al ₂ O ₃ material. Accordingly, the same reference numerals are used for the same or the same functions as those of the light emitting device 50 of FIG. In addition, in FIG. 6, illustration of a metal base part is abbreviate | omitted.

  The metal reflecting mirror 61 is formed of a copper material, and 16 recesses for forming the 16 reflecting surfaces 61a are formed at predetermined intervals by press molding so that each of the LED elements 54a to 54p is centered. Is provided. The reflection surface 61a is formed by applying mirror finishing by silver vapor deposition, silver plating or the like, or white or silver surface treatment on the inner surface of each of the 16 recesses. The reflective surface 61a is Ni-plated as a base, and silver deposition or silver plating is performed only in the recesses. Ni plating is characterized by excellent adhesion to glass, and the anti-peeling property is improved.

  The metal reflecting mirror 61 is bonded to the holding member 53 via an oxide based on a heat treatment at about 900 ° C. A sealing member 62 is filled at a predetermined height in the sixteen reflecting surfaces 61 a and on the metal reflecting mirror 61. The sealing member 62 is made of glass having the same material and characteristics (thermal expansion coefficient and the like) as the sealing member 14 in the above embodiment.

According to the fourth embodiment described above, the following effects can be obtained in addition to the preferable effects of the first, second, and third embodiments.
(1) Since the metal reflecting mirror 61 having 16 reflecting surfaces 61a corresponding to each of the LED elements 54a to 54p is disposed on the holding member 53, the light from the LED elements 54a to 54p is reflected according to the reflection shape. Can be effectively taken out in the desired direction.
(2) Since the thermal expansion coefficient of the sealing member 62 is equal to that of the holding member 53 and the metal reflecting mirror 61, the metal reflecting mirror 61 may be provided between the sealing member 62 and the holding member 53. Stress due to temperature does not occur, and interface peeling or the like does not occur.

  FIG. 7 is a partial cross-sectional view showing a modification of the holding member according to the fourth embodiment. Here, only the vicinity of the LED element 54i is illustrated, and the others are omitted.

  The holding member 70 is a multilayer substrate formed by laminating wiring patterns in a cross section, copper foil layers 71 and 76 are formed on the lower surface and the upper surface, and an internal wiring layer connected to the LED element 54i inside. 72 is provided. The internal wiring layer 72 is provided to bypass the wiring layer 73 for heat dissipation, and the wiring layer 73 is a heat transfer path for radiating heat from the copper foil layers 71 to 76. A copper foil layer 74 is formed on the lower surface of the element mount portion 52i, and a through hole 75 for connecting the electrode of the LED element 54i and the internal wiring layer 72 is formed therein.

Thus, by providing the wiring layer 73 that becomes a heat transfer path, the heat generated by the LED element 54i is transferred to the element mount portion 52i, the copper foil layer 74, a metal base (not shown), the copper foil layer 71, The wiring layer 73 and the copper foil layer 76 can be easily transmitted to the metal reflecting mirror 61, so that the heat dissipation can be improved.

  8A and 8B are diagrams showing the configuration of the optical device according to the fifth embodiment. FIG. 8A is a cross-sectional view showing the basic configuration of the light emitting apparatus according to the fifth embodiment, and FIG. It is sectional drawing which shows the modification of (). The light emitting device 80 according to the fifth embodiment is characterized in that a metal plate which is a conductor is used for the holding member, whereas each of the above embodiments uses an insulator for the holding member.

  The light emitting device 80 includes an LED element 81, an element mount portion 82 on which the LED element 81 is mounted on the uppermost surface, a metal plate 83 in which the element mount portion 82 is fitted into one through hole, and the LED element 81 and the metal plate 83. And a sealing member 84 that seals the upper surface of the substrate.

  The LED element 81 and the element mount portion 82 are the same as the LED element 11 and the element mount portion 12 of the light emitting device 1. The element mount portion 82 has protrusions 82 a and 82 b formed at intermediate portions on both sides, and is mounted on the metal plate 83 so that the upper surfaces of the protrusions 82 a and 82 b are in contact with the through holes of the metal plate 83. . Electrodes 82c and 82d are provided on the lower surfaces of the protrusions 82a and 82b. In order to connect the electrodes 82c and 82d and the electrode 81a (or solder bump) of the LED element 81, a through-hole is provided in the element mount 82. Holes 82e and 82f are provided. An electrode 82A that is electrically connected to the electrode 81a is provided on the upper surface. The electrodes 82c and 82d are supplied with power from a power supply device. However, the electrodes 82c and 82d can be directly supplied with power, or can be separately provided through a substrate.

  The metal plate 83 functions as a radiator, and a metal such as copper having high thermal conductivity is used as the material, and the tip is processed to have a step. As with the sealing member 14 of the light emitting device 1, the sealing member 84 is made of low melting point and translucent glass and has a thermal expansion coefficient equivalent to that of the metal plate 83 that is a holding member.

  Below, the assembly procedure of the light-emitting device 80 is demonstrated. First, the element mount 82 is inserted into the through hole of the metal plate 83 from the lower side of FIG. Next, the LED element 81 is mounted on the upper surface of the element mount portion 82. Next, if the sealing member 84 is sealed, the light emitting device 80 is completed.

  Alternatively, the LED element 81 may be mounted on the upper surface of the element mount portion 82 and then the element mount portion 82 may be fitted into the through hole of the metal plate 83. In addition, a configuration in which a reflecting mirror is provided on the surface of the metal plate 83 is also possible.

  According to the fifth embodiment described above, in addition to the preferable effects of the first and second embodiments, the metal plate 83 functions as a holding member that holds the element mount portion 82 and also functions as a radiator. Accordingly, a certain degree of heat dissipation effect can be obtained without providing a metal base portion, and thus the optical device can be made thinner.

  As described above, a considerable heat radiation effect can be obtained by the metal plate 83 even in the configuration of FIG. However, when it is desired to further enhance the heat dissipation effect, a metal base portion made of copper or aluminum may be added as shown in FIG. The light emitting device 85 shown in FIG. 8B is mounted by solder welding using a solder layer 82g provided on the lower surface of the element mount portion 82. A polyimide substrate 86 as an insulating substrate is disposed on the lower surface of the metal plate 83. A wiring layer (not shown) is formed inside the polyimide substrate 86, and electrodes 82c and 82d are connected to the wiring layer.

  FIGS. 9A and 9B are diagrams showing a modification example relating to the connection of the polyimide substrate, in which FIG. 9A is a cross-sectional view and FIG. 9B is a bottom view of the element mounting portion. The polyimide substrate 86 is configured by laminating a wiring layer 86a connected to the electrode 82c serving as the cathode and a wiring layer 86b connected to the electrode 82d serving as the anode, and is connected to one of the element mounting portions 82. Yes.

  With such a configuration, a simple wiring between the polyimide substrate 86 and the element mounting portion 82 can be realized. Further, the side where the polyimide substrate 86 is not provided can be used as a heat transfer path to the metal base portion 87, and is excellent in heat drawability.

  FIG. 10 is a partial cross-sectional view of an optical device showing another modification of the fifth embodiment. In FIG. 10, the same reference numerals are given to the members having the same or the same function as the members shown in FIG.

  The light emitting device 90 uses a metal plate 91 in which the thickness of the metal plate 83 in FIG. 8 is increased, and an element mount portion 82 is inserted into a through-hole 90 a provided at a predetermined position of the metal plate 91. A concave portion is formed in the shape of a mortar in the upper portion of the through hole 90a (formed so that the bottom surface of the concave portion is substantially flush with the upper surface of the element mount portion 82), and a reflection surface 91b is formed on the inner surface of the concave portion. Yes. The reflective surface 91b is formed by a white or silver coating or the like in addition to a mirror finish by silver vapor deposition, silver plating or the like. Furthermore, a sealing member 84 made of low-melting glass is filled so as to fill the reflecting surface 91b and to have a predetermined thickness on the upper portion of the metal plate 91.

  In the element mounting portion 82, the electrode 82A formed on the upper surface is electrically connected to the corresponding electrodes 82c and 82d by the internal wiring layer.

  The sealing member 84 is not limited to the low melting point glass described above, and may be an epoxy resin or a silicon resin. It is difficult to achieve the thermal expansion coefficient at the metal level of low melting point glass with resin, and the thermal expansion coefficient is several times higher than that of metal, but the expansion is large because the processing temperature is lower than the processing temperature of low melting glass. Since the metal plate 83 as a holding member does not have a small thermal conductivity like the element mount portion, it is possible to prevent peeling and cracking.

  According to the fifth embodiment described above, the light emission efficiency of the LED element 81 is improved by forming the reflective surface 91b on the metal plate 91 in addition to the fourth embodiment. Furthermore, since the thickness of the metal plate 91 is increased in order to provide the reflecting surface 91b, the heat dissipation resistance as a radiator can be reduced, and thus the heat dissipation efficiency can be increased.

  FIG. 11 is a partial cross-sectional view showing the configuration of the optical device according to the sixth embodiment. While each of the above embodiments uses a face-down type LED element, this embodiment is an optical device using a face-up type LED element that is connected to the power supply side with a wire. There are features.

  The light emitting device 100 includes an LED element 101, an element mount portion 102 on which the LED element 101 is mounted, a holding member 103 that holds the element mount portion 102, wiring layers 102 a and 102 b of the element mount portion 102, and the LED element 101. Wires 104a and 104b for connecting the electrodes (not shown), a first sealing member 105 as a heat-resistant member for sealing the LED element 101, the wires 104a and 104b and their surroundings, and the first sealing. The stopper member 105 and the second sealing member 106 that seals the exposed surface of the upper surface of the holding member 103 are provided.

  The LED element 101 is configured using a semiconductor similar to the LED element 11 although the type is different. The element mount unit 102 and the holding member 103 are made of the same material and thermal expansion coefficient as the element mount unit 12 and the holding member 13. The holding member 103 is formed with a through hole into which the element mount portion 102 is inserted, and electrodes 103 a and 103 b are provided on the lower surfaces of the protruding portions on both sides. The electrodes 103 a and 103 b are connected to the wiring layers 102 a and 102 b of the element mount portion 102 through a wiring layer (broken line) provided inside the holding member 103.

  Au wires and aluminum wires are used for the wires 104a and 104b. The wires 104a and 104b may be deformed or crushed by the press-fitting of the sealing member 106. Therefore, the first sealing member 105, which is a ceramic coat member serving as an intermediate thermal expansion member between the element mounting portion 102 and the second sealing member 106, is used for sealing the wires 104a and 104b. The deformation and crushing of the wires 104a and 104b are prevented. The second sealing member 106 sealed so as to cover the first sealing member 105 has a thermal expansion coefficient equivalent to that of the holding member 103, and stress is generated on the contact surface with other members. It is preventing.

  In FIG. 11, for the sake of explanation, the portion where the element mounting portion 102 is exposed from the holding member 103 is illustrated so as to be larger than the size of the LED element 101, but a wire bonding space is actually provided. It is desirable that the size of the LED element is substantially the same as the LED element size within twice the area of the LED element 101. In particular, if the first sealing member 105 has a buffering effect such as an elastic material or a thermal expansion coefficient member intermediate between the element mounting portion 102 and the second sealing member 106, the exposed portion is It may be large.

  Next, a manufacturing process of the light emitting device 100 will be described.

  First, the element mount 102 is inserted into the through hole provided at a predetermined position of the holding member 103 from the lower side of the drawing. In the element mount portion 102, wiring layers 102a and 102b are provided in advance. Next, the LED element 101 is mounted at a predetermined position of the element mount portion 102. Next, an electrode (not shown) on the upper surface of the LED element 101 and the wiring layers 102a and 102b are bonded by wires 104a and 104b. The first sealing member 105 is sealed so as to enclose the wires 104a and 104b. Further, the second sealing member 106 is sealed so as to enclose the first sealing member 105.

  According to the sixth embodiment described above, since the sealing member has a double structure, the wires 104a and 104b are protected from the applied pressure during sealing, and the wires 104a and 104b may be deformed or crushed. Even if the face-up type LED element 101 is used, the same effect as the above-described embodiment can be obtained.

  FIG. 12 is a partial cross-sectional view showing the configuration of the optical device according to the seventh embodiment. In the light emitting device 110 according to the seventh embodiment, the first sealing member 105 uses a silicone resin that is an elastic member and uses a face-down element (flip chip), and the manufacturing process thereof is the sixth embodiment. Unlike the light emitting device 100 of the embodiment, the same parts as those in FIG.

  To manufacture the light emitting device 110, first, the holding member 103 is set in a mold whose glass contact surface is made of platinum. This mold has a shape corresponding to a convex depression for fitting the element mounting portion 102, and a portion protruding from the upper surface of the holding member 103 is a hemisphere corresponding to the shape of the element housing space shape surface 106b. It has a shape. Next, the low melting point glass is heated to bond the second sealing member 106 and form the lens surface 106a and the LED element storage space forming surface 106b. Next, a silicone resin serving as the first sealing resin 105 is injected into the LED element storage space inside the LED element storage space forming surface 106b and cured. Next, the LED element 101 is mounted on the element mounting portion 102. Next, the element mount portion 102 is fitted into the through hole provided at a predetermined position of the holding member 103 from the lower side of FIG. 12, and the holding member 103 and the element mount portion 102 are fixed using a brazing material. . At this time, the silicone resin has elasticity, and by pressing the LED element 101, it is deformed into a shape corresponding to the surface shape of the LED element 101, and the LED element 101 can be sealed.

  For fixing the element mounting portion 102, a solder material can be used in addition to the brazing material.

According to the seventh embodiment described above, the following effects are obtained.
(1) Providing a metal base on the lower side of the figure prevents moisture and the like from entering as in the second embodiment.
(2) LED element 101 with low heat resistance can be used without exposing LED element 101 to a high-temperature atmosphere during glass processing. Or not only low melting glass but glass with high melting | fusing point can be used.
(3) Since the first sealing member 105 is covered with the second sealing member 106 made of a glass member, the shape of the lens surface 106a can be maintained as an optical device. A pure silicone resin is less susceptible to deterioration by heat or light, but an additive for curing the resin becomes a color change factor. According to the seventh embodiment, the first sealing member 105 is made of an oily pure silicone resin, so that the light output is not easily lowered due to deterioration due to heat or light, and is highly reliable. be able to.

  In the light emitting devices 1, 30, 50, 60, 80, 85, 90, 100, and 110 described above, a phosphor layer for wavelength conversion can be disposed in the glass sealing portion. The phosphor layer is, for example, a phosphor such as Ce (cerium): YAG (yttrium, aluminum, garnet) having a characteristic of emitting yellow light when excited by the blue light when the LED element emits blue light. Can be used.

  Further, in each of the above embodiments, heat radiation fins can be formed or attached to the metal base portions 15, 32, 51, 87, the metal plates 83, 90, and the metal reflector 61. Thereby, the heat dissipation effect can be further enhanced.

  Furthermore, although the sealing members 14 and 35 are formed in a flat shape, the shape is not limited to this, and may be, for example, a shell type or a diamond cut type.

  Further, the present invention is not limited to the light emitting device, and can be applied to, for example, an optical device such as a semiconductor device using a light receiving element such as a solar cell, and the sealing member is glass. Even if it is exposed to light for a long time, it does not deteriorate, and it can be used as an optical device as a solar cell provided with a condensing lens and having a small light receiving element size. By applying the present invention, a decrease in conversion efficiency accompanying a temperature rise is suppressed, and weather resistance, heat resistance, and the like can be improved.

It is a figure which shows the structure of the optical device which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is AA sectional drawing. It is a fragmentary sectional view which shows the modification of the holding member in the optical device of 1st Embodiment. It is a figure which shows the structure of the optical device which concerns on 2nd Embodiment, (a) is sectional drawing, (b) is a schematic plan view which shows the arrangement | positioning state of a solder layer and a metal lead. It is a figure which shows the modification of the holding member in 2nd Embodiment, (a) is the structure which provided the reflecting film in the holding member surface, (b) is the structure which provided the reflecting film in the recessed part of the holding member. . It is a figure which shows the structure of the optical device which concerns on 3rd Embodiment, (a) is a top view, (b) is BB sectional drawing of (a). It is a figure which shows the structure of the optical device which concerns on 4th Embodiment, (a) is a top view, (b) is CC sectional drawing of (a). It is a fragmentary sectional view showing the modification of the holding member of a 4th embodiment. It is a figure which shows the structure of the optical device which concerns on 5th Embodiment, (a) is sectional drawing which shows the basic composition of the optical device which concerns on 5th Embodiment, (b) is a modification of (a). FIG. It is a fragmentary sectional view of the optical device which shows the modification of 5th Embodiment. It is a fragmentary sectional view of the optical device which shows the other modification of 5th Embodiment. It is a fragmentary sectional view showing the composition of the optical device concerning a 6th embodiment. It is a fragmentary sectional view showing the composition of the optical device concerning a 7th embodiment.

Explanation of symbols

1, 20, 30, 50, 60, 80, 85, 90, 100, 110 Light-emitting device 11 LED element 11a Electrode 12 Element mount 12a, 12b, 13a, 13b Wiring layer 12c Solder layer 13 Holding member 14 Sealing member 15 Metal base part 15a Convex part 21 Element mount part 21a, 21b, 21c Electrode 22a, 22b, 22c LED element 31 Element mount part 32 Metal base part 33 Holding member 33a, 33b Electrode 33c Solder layer 33d, 33e, 33g Concave part 33f, 33h Reflective film 34a, 34b Metal lead 35 Sealing member 41 Through hole 51 Metal base portion 52a-52p Element mount portion 53 Holding member 54a-54p LED element 55 Sealing member 56a-56e Terminal 57a-57d Power supply terminal 58, 71, 74,76 Copper foil layer 61 Metal Mirror 61a Reflecting surface 62, 70 Sealing member 72 Internal wiring layer 73, 75 Through hole 81 LED element 81a Electrode 82 Element mounting part 82a, 82b Protruding part 82c, 82d Electrode 82e, 82f Through hole 82g Solder layer 83 Metal plate 84 Sealing Stop member 86 Polyimide substrate 90a Through hole 91 Metal plate 92 Reflecting surface 101 LED element 102 Element mounting portion 102a, 102b Wiring layer 103 Holding member 104a, 104b Wire 105 First sealing member 106 Second sealing member R1-R4 resistance

Claims (11)

An optical element;
Mounting the optical element, the thermal expansion coefficient is equivalent to that of the optical element, and the area of the surface on which the optical element is mounted has an element mounting portion that is twice or less the optical element ;
Includes a hole for fitting the element mount portion, and a large consisting holding member of the element mounting portion by Rinetsu expansion,
It said optical element have a light-transmitting property with respect to the wavelength of interest as well as sealing, and a sealing member formed of a glass material,
The element mounting portion is disposed so that a surface on which the optical element is mounted is exposed from the hole of the holding member on the sealing member side, and the holding member and the sealing member are joined ,
An optical device , wherein a difference in thermal expansion coefficient between the holding member and the sealing member is within 15% with respect to a thermal expansion coefficient of the holding member . The optical element is plural,
The optical device according to claim 1, wherein the element mounting portion is provided for each of the plurality of optical elements and is arranged in an island shape . Before Kifu stop member, the second sealing for sealing the first sealing member for sealing the optical element and the periphery thereof, the exposed surface of the upper surface of the first sealing member and the retaining member With members,
It said first sealing member is an optical device according to claim 1 or 2, characterized in that have a thermal expansion coefficient intermediate between the second sealing member and the element mounting portion. The element mounting portion, the optical device according to any one of claims 1 to 3, characterized in that it is formed in the holding member and the concave-convex can fit a convex cross section. The holding member is an optical device according to claim 1, any one of 4 to characterized in that it consists of a ceramic material. The optical device according to claim 5, wherein the holding member is made of a glass-containing Al ₂ O ₃ material. The optical device according to claim 5 , wherein the holding member is a multilayer substrate in which wiring patterns are laminated in a cross section. The optical element, the optical device according to any one of claims 1 to 7, characterized in that a light-emitting element. The optical device according to claim 8, wherein the optical element is flip-chip bonded. The optical device according to claim 8, wherein the optical element is a face-up type light emitting element, and is covered with a heat resistant material together with a wire electrically connected to the light emitting element. The element mounting portion, the optical device according to any one of claims 1 to 10, characterized in that it has a heat radiating portion on the bottom surface.