JP2019145762A - Lid body for optical device and optical device - Google Patents

Abstract

To provide a lid body for an optical device that can reduce the size (reduce the thickness) of the optical device and is excellent in airtight reliability.SOLUTION: A lid body 10 for an optical device comprises: a frame member 1 formed of a metal plate; a frame body 2 smaller than the frame member 1 in plan view and having a step part 2a notched from an under surface through an inside surface; and a plate-like translucent member 3. The frame member 1 has its outer edge part projecting from an outer edge of the frame body 2 and joined to a top face of the frame body 2 with a first joint material 4, and the translucent member 3 is joined to the step part 2a of the frame body 2 with a second joint material 5 at an outer edge part of a top face and side faces.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a lid for an optical device and an optical device that are used in an optical device on which an optical element such as a light emitting element or an imaging element is mounted.

Imaging devices such as CCD (Charged-Coupled Device) and CMOS (Complementary Metal-Oxide Semiconductor), MEMS (Micro Electro Mechanical Systems) devices such as optical switches and mirror devices, laser diodes (LD) and L
As a lid for an optical device in which an optical element such as a light emitting element such as an ED (Light Emitting Diode) is mounted, a lid made of a metal frame member and a translucent member that closes the opening of the frame member (For example, refer to Patent Document 1). An optical element is mounted on the package, a lid is bonded to the upper surface of the package, and the element is hermetically sealed to provide an optical device.

  As this lid, in order to reduce the stress applied to the translucent member made of glass or the like, there is one in which a frame made of ceramic is disposed between the metal frame member and the translucent member (for example, (See Patent Document 2). The frame body and the translucent member are joined by glass or the like, and the frame member joined to the frame body by a brazing material or the like is joined to the seal ring or the like of the package by seam welding or the like.

JP 2003-282754 A JP2015-195330A

  In recent years, there is an increasing demand for miniaturization of optical devices in order to cope with the miniaturization of optical devices using the optical devices. However, in the conventional lid, since the translucent member is disposed on the frame, it is difficult to reduce the size (thinning). If the frame is placed under the frame member, the thickness can be reduced. However, since the translucent member is arranged on the frame, the distance between the optical element and the translucent member is increased. there were. If the distance between the optical element and the translucent member is large, in the case of an optical element that emits light at a wide angle, the translucent portion, that is, the opening of the frame body and the frame member must be enlarged, and miniaturization is difficult. there were.

  On the other hand, there is a case where a plurality of optical elements are mounted while demand for miniaturization is required. In that case, the element mounting portion and the translucent member must be made as large as possible. For this reason, the lid for an optical device must be reduced in size as a whole, for example, by reducing the width of a metal frame member. However, in the conventional lid for an optical device, when the frame is disposed under the frame member and is downsized (thinned), the translucent member is disposed on the frame, so the package of the frame member The part to be joined to the transparent member and the transparent member are close to each other, and the heat at the time of joining the frame member to the package may cause a crack in the joining material such as glass that joins the transparent member and the frame. there were. As a result, airtight reliability may be reduced.

An optical device lid according to one aspect of the present disclosure includes a frame member made of a metal plate, a frame body having a stepped portion that is smaller in plan view than the frame member and is notched from the lower surface to the inner surface, and a plate-like member. A translucent member, and the frame member has an outer edge protruding from the outer edge of the frame body and joined to the upper surface of the frame body by a first bonding material, and the translucent member includes an outer edge portion of the upper surface and A side surface is joined to the step portion of the frame body by a second joining material.

  An optical device according to an aspect of the present disclosure includes the above-described optical device lid, a package, and an optical element mounted on the package.

  According to the lid for an optical device of the present disclosure, the frame member is bonded to the inner side of the lower surface of the frame member, and the translucent member is bonded to the lower inner side of the frame member. Since the distance between the outer edge of the frame, the frame, and the second bonding material for bonding the translucent member is increased, the influence of heat on the second bonding material when bonded to the package is small, and airtight reliability Will improve. In addition, since the translucent member is positioned at the lowest position, the distance from the optical element mounted on the package is short, and an optical device capable of emitting light at a wide angle even with a small size can be obtained.

  According to the optical device of the present disclosure, since the lid for the optical device is used, the optical device is small and has excellent reliability of hermetic sealing.

(A) is a perspective view which shows an example of the cover body for optical apparatuses, (b) is an exploded perspective view which decomposes | disassembles and shows (a), (c) is the cross section in the CC line of (a). FIG. (A) is sectional drawing which expands and shows the A section of FIG.1 (c), (b) is sectional drawing which expands and shows the principal part of another example. (A) And (b) is sectional drawing which expands and shows the principal part of another example of the cover for optical devices. (A) And (b) is a top view (bottom view) which shows the cover body for optical devices shown in FIG. It is a perspective view which shows an example of an optical apparatus. (A) is sectional drawing in the AA line of FIG. 5, (b) is sectional drawing in the BB line of FIG.

  Hereinafter, the lid for an optical device and the optical device according to the present disclosure will be described with reference to the drawings. In addition, the distinction between the upper and lower sides in the following description is for convenience, and does not limit the upper and lower sides when the optical device lid or the like is actually used. FIG. 1A is a perspective view showing an example of a lid for an optical device, FIG. 1B is an exploded perspective view showing FIG. 1A in an exploded view, and FIG. It is sectional drawing in the CC line of (a). FIG. 2A is an enlarged cross-sectional view showing a portion A of FIG. 1C, and FIG. 2B is a cross-sectional view showing another example. FIG. 3A and FIG. 3B are both cross-sectional views showing an enlarged main part of another example of the lid for an optical device. 4 (a) and 4 (b) are plan views (bottom view) of the optical device lid shown in FIG. 3 as seen from the frame body side, with the second bonding material omitted. Yes. Although not a cross-sectional view, the concave portions are hatched so as to be easily distinguished. FIG. 5 is a perspective view showing an example of the optical device, and shows a state in which the lid for the optical device is removed. 6A is a cross-sectional view taken along line AA in FIG. 5, and FIG. 6B is a cross-sectional view taken along line BB in FIG.

  As shown in the example shown in FIG. 1, the optical device lid 10 includes a frame member 1 made of a metal plate, and a stepped portion 2 a that is smaller than the frame member 1 in plan view and cut out from the lower surface 22 to the inner surface 23. A frame 2 and a plate-like translucent member 3 are provided. In the frame member 1, the outer edge portion 1 a protrudes from the outer edge of the frame body 2 and is bonded to the upper surface 21 of the frame body 2 by the first bonding material 4. In the translucent member 3, the outer edge portion and the side surface 33 of the upper surface 31 are joined to the step portion 2 a of the frame body 2 by the second joining material 5.

  According to the optical device lid body 10 having such a configuration, the frame body 2 is bonded to the inner side of the lower surface of the frame member 1, and the translucent member 3 is bonded to the lower inner side of the frame body 2. The distance between the outer edge portion 1a of the frame member 1 that is a portion to be bonded to the package 6 and the second bonding material 5 that bonds the frame body 2 and the translucent member 3 is increased. Therefore, the influence of heat on the second bonding material 5 when bonded to the package 6 by a method such as seam weld becomes small, and the stress applied from the frame member 1 to the frame body 2 is alleviated and the second bonding material is reduced. Since the stress applied to 5 is also reduced, the airtight reliability is improved. In addition, since the translucent member 3 is positioned at the lowest position, the optical device 100 that is close in distance to the optical element 7 mounted on the package 6 and can emit light at a wide angle even with a small size is obtained. Can do. Moreover, since the frame 2 and the frame member 1 are located outside the translucent member 3 when the optical device lid 10 is attached to the package 6, the possibility that the translucent member 3 is damaged is reduced. Therefore, the possibility that the optical characteristics of the optical device 100 deteriorate is reduced.

  As in the example shown in FIG. 2, the frame member 1 and the frame body 2 are joined to the outside of the step portion 2 a. In the example shown in FIG. 2A, the inner side surface 13 of the frame member 1 is located outside the stepped portion 2a of the frame body 2, whereas in the example shown in FIG. 1 is located on the inner side of the stepped portion 2 a of the frame 2. However, in any example, the frame member 1 and the frame body 2 are joined outside the stepped portion 2a. In other words, the first bonding material 4 that joins the frame member 1 and the frame body 2 is positioned outside the step portion 2a on the frame body 2 side.

  In such a configuration, the stress applied to the corner of the stepped portion 2a which is a notch provided in the frame 2, in other words, the corner on the inner side of the L-shaped frame 2 having a bent cross-sectional shape is applied. It can be made small, and the possibility that cracks and the like are generated by this stress and the airtight reliability is lowered can be reduced. This stress is generated when the optical device lid 10 is bonded to the package 6, due to heat generated when the frame member 1 and the frame 2 are bonded, or heat generated when the optical element 7 is operated. And the thermal stress generated between the frame 2 and the frame 2. When the upper surface 21 of the frame body 2 is joined to the inner side of the stepped portion 2a, thermal stress acts on the upper surface 21 in the surface direction of the upper surface, and the corner of the stepped portion 2a expands or narrows on the frame body 2. Such distortion occurs. If it is joined outside the stepped portion 2a, such strain due to thermal stress can be reduced.

  On the surface of the frame member 1, a plating film can be provided for preventing the corrosion of the frame member 1, bonding properties between the frame member 1 and the frame body 2, and bonding properties with the package 6. As this plating film, a metal plating film such as Ni (nickel) or Au (gold) can be used. Ni is more advantageous than Au in terms of cost.

  And it can be set as the cover 10 for optical apparatuses by which the surface of the frame member 1 is covered with Ni plating film containing Co (cobalt) or Cr (chromium) among Ni plating. When Co or Cr is contained in the Ni plating film, an alloy of Ni and Co or Cr is formed to increase the electric resistance of the plating film, while the melting point is about the same as that of Ni plating. Therefore, when the frame member 1 and the package 6 are joined by resistance welding such as seam weld, heat is easily generated by the plating film located on the surface of the frame member 1. That is, since it is possible to perform bonding by local heating at the surface portion of the frame member 1, the amount of heat generated in the entire frame member 1 is reduced, and the influence on the second bonding material 5 is small. Since the stress applied to the frame body 2 is relaxed and the stress applied to the second bonding material 5 is also reduced, the airtight reliability is improved. When Co and Cr are compared as metals contained in Ni plating, the crystal structure of Co is less likely to change when an alloy is formed with Ni, so that the quality of the Ni plating film can be kept more constant.

The surface of the frame member 1 can be covered with a Ni plating film containing B. Since the Ni plating film containing B (nickel plating film containing boron) has high heat resistance, the frame body 2 and the translucent member 3 are joined after the frame member 1 and the frame body 2 are joined. It is difficult to change the quality due to the heat, and the influence on the bonding property between the optical device lid 10 and the package 6 can be reduced. Therefore, it is possible to obtain the optical device 100 having high bonding reliability and airtight reliability between the optical device lid 10 (the frame member 1 thereof) and the package 6.

  As described above, the translucent member 3 is joined to the step portion 2 a of the frame 2 by the second joining material 5. More specifically, the stepped portion 2 a has a stepped surface 24 along the upper surface 21 and the lower surface 22, and a stepped side surface 25 that intersects the stepped surface 24 and extends along the inner surface 23. As shown in the example shown in FIGS. 2A and 2B, the outer edge portion of the translucent member 3 is disposed in a space surrounded by the step surface 24 and the step side surface 25. The outer edge portion of the upper surface 31 and the side surface 33 are joined by the second joining material 5. In the example shown in FIG. 2B, the second bonding material 5 extends from the step side surface 25 to the outer edge portion of the lower surface 32 of the translucent member 3, and the outer edge portion of the lower surface 32 of the translucent member 3 also has a step. It is joined to the part 2a. In the example shown in FIGS. 2A and 2B, the second bonding material 5 is also disposed from the inner side surface 23 of the frame body 2 to the upper surface 31 of the translucent member 3. The inner side surface 23 of the body 2 and the outer edge portion of the upper surface 31 of the translucent member 3 are also joined. The second bonding material 5 protrudes inward from the inner side surface 23 of the frame body 2 and is also positioned inward of the inner side surface 23 of the frame body 2.

  In contrast, as in the example shown in FIGS. 3A and 3B, the second bonding material 5 does not protrude beyond the inner side surface 23 of the frame body 2, that is, the second bonding material 5. Can be positioned outside the inner surface 23 of the frame 2. In this case, light reflection or the like does not occur at a portion of the second bonding material 5 that protrudes inward from the inner side surface 23 of the frame 2. Since unnecessary light due to reflection by the second bonding material 5 inside the inner side surface 23 is not generated, for example, when the optical element 7 is a light emitting element, unnecessary light is prevented from being mixed into the light emitted from the element. In addition, when the optical element 7 is a light receiving element such as an imaging element, it is possible to prevent unnecessary light from being received by the light receiving element, so that the optical characteristics of the optical device 100 are excellent. .

  In the example shown in FIGS. 3A and 3B, the frame 2 has a recess 24a on the step surface 24 of the step 2a, and the second bonding material 5 enters the recess 24a. Yes. In order to prevent the second bonding material 5 from protruding inward from the inner side surface 23 of the frame body 2, the amount and arrangement position of the second bonding material 5 may be adjusted. If there is, the second bonding material 5 can be more easily prevented from protruding inside the inner side surface 23 of the frame body 2. When the second bonding material 5 is bonded to the translucent member 3 and the frame body 2, the molten second bonding material 5 easily flows into the recess 24 a and accumulates therein, so that the inner side surface 23 of the frame body 2 is inside. It is difficult to flow into Further, since the second bonding material 5 enters the recess 24 a of the frame body 2, the bonding area between the second bonding material 5 and the frame body 2 increases, and the second bonding material 5 bites into the frame body 2. Since it becomes an oval shape, the bonding strength and the bonding reliability between the second bonding material 5 and the frame 2 are improved. This is the same even when the second bonding material 5 protrudes inside the inner surface 23 of the frame 2.

Since the concave portion 24a is for suppressing the flow to the inside of the second bonding material 5 as described above, the concave portion 24a is provided over the entire step surface 24, that is, over the entire circumference. In the example shown in FIG. 4A, the recess 24 a is a continuous annular groove extending along the inner surface 23. Since the recesses 24a having the same width are provided over the entire circumference, the inward flow of the second bonding material 5 can be suppressed uniformly over the entire circumference, and the bonding between the second bonding material 5 and the frame body 2 can be suppressed. The strength is also uniform. However, the recess 24a is not a continuous annular groove, but may have a shape obtained by dividing the annular groove into a plurality of circumferential directions, or a plurality of dot-like shapes as in the example shown in FIG. The recesses 24a may be arranged in the circumferential direction. In any case, if the interval between the plurality of recesses 24a is small, the flow to the inside of the second bonding material 5 can be suppressed almost uniformly over the entire circumference, and the second bonding material 5 and the frame 2 The bonding strength is also substantially uniform. Alternatively, the dot-shaped recesses 24a may be arranged so as to partially overlap each other to form a groove shape whose width varies periodically in the circumferential direction, that is, the width is not constant. In addition, if the overlap of the dotted | punctate recessed part 24a is large, it will become a groove shape with fixed width. The longitudinal cross-sectional shape of the recess 24a is not limited to the semicircular shape as in the example shown in FIG. 3, and may be, for example, a triangular shape or a quadrangular shape.

Moreover, it can be set as the optical apparatus cover body 10 provided with the optical film in at least one of the upper surface 31 and the lower surface 32 of the translucent member 3. The optical characteristics of the optical device lid 10 and the optical device 100 can be further improved. The optical filter film is, for example, an optical filter film such as an antireflection film (AR coding: Anti-Reflection Coating), a UV (Ultra Violet) cut filter, an IR (infrared rays) cut filter, or a light shielding film. . For example, magnesium fluoride (MgF ₂ ), silicon dioxide (SiO ₂ ), lanthanum fluoride (LaO ₃ ), lanthanum oxide (La ₂ O ₃ ), tantalum pentoxide can be used as the antireflection film or the optical filter film. (Ta ₂ O ₅ ), titanium pentoxide (Ti ₃ O ₅ ), niobium pentoxide (Nb ₂ O ₅ ), zirconium oxide (ZrO ₂ ), titanium oxide (TiO ₂ ), or a mixture of ZrO ₂ + TiO ₂ , etc. The dielectric single layer film or multilayer film can be used. The light shielding film can be formed of, for example, a metal film such as chromium (Cr) or chromium oxide (CrOx), or a thermosetting resin such as an epoxy resin colored black by adding carbon.

  The optical device 100 includes the optical device lid 10 as described above, a package 6, and an optical element 7 mounted on the package 6. Since the optical device lid 10 as described above is used, the optical device lid 10 is small and has excellent airtight sealing reliability.

In the example shown in FIGS. 5 and 6, the package 6 includes a base 61 made of metal and a frame 62 made of metal joined to the base 61 to form a container for storing the basic optical element 7. ing. The base 61 and the frame portion 62 are joined together by a metal brazing material using, for example, a silver-copper (Ag—Cu) alloy. The frame portion 62 has a through-hole penetrating from the inner surface to the outer surface of the frame portion. A rod-like terminal 63 is inserted into the through hole, and is fixed with an insulating sealing material 64 such as glass and hermetically sealed. The upper surface of the frame portion 62 of the package 6 and the lower surface of the outer edge portion 1a of the frame member 1 of the optical device lid 10 are joined by welding such as seam weld. Thus, the optical device 100 in which the optical element 7 mounted on the base body 61 is hermetically sealed inside the frame portion 62 is formed.

  The frame member 1 is made of a thin metal plate, has an outer shape corresponding to the frame portion 62 of the package 6, and has a frame shape having a through hole smaller than the inner dimension of the frame portion 62 at the center. The inner edge portion of the lower surface of the frame member 1 serves as a bonding surface with the frame body 2 that is bonded to the outer peripheral portion of the upper surface of the frame body 2 with the first bonding material 4. Further, on the lower surface of the frame member 1, an outer edge portion that protrudes outward from the outer edge of the frame body 2 when bonded to the frame body 2 is a bonding surface with the frame portion 62.

Since the frame member 1 is partially heated to a high temperature when it is joined to the frame portion 62 by a welding method such as seam weld, the thermal expansion is small so that thermal stress due to shrinkage during cooling after joining does not increase. Those having a coefficient are preferred. For example, 42 alloy (coefficient of thermal expansion of about 5.0 × 10 ⁻⁶
/ Ni) Co17 alloy (coefficient of thermal expansion of about 4.8 × 10 −6 / ° C.) can be used for the frame member 1 as having a small coefficient of thermal expansion.

  Further, the frame member 1 is penetrated into a region including the central portion by using a conventionally known etching method or press working method on a thin metal plate having a thickness of about 0.05 to 0.2 mm, for example. It can be of a frame shape having holes.

  As described above, a plating film can be provided on the surface of the frame member 1 in order to prevent corrosion of the frame member 1, bondability between the frame member 1 and the frame body 2, and bondability with the package 6. A plating film can be formed by a conventionally known electrolytic plating method or electroless plating method.

  The frame body 2 is a frame-shaped member having an outer dimension that is larger than the inner dimension of the frame member 1 and smaller than the outer dimension and smaller than the inner dimension of the frame portion 62 of the package 6. The frame body 2 has a stepped portion 2 a that is cut out from the lower surface 22 to the inner surface 23. In other words, the frame 2 has a frame shape in which the outer size is the same between the upper portion and the lower portion, but the inner size is larger in the lower portion.

  The frame 2 is made of a material having higher rigidity than the translucent member 3 such as a ceramic material. If the frame 2 is made of, for example, an aluminum oxide sintered body, it can be manufactured as follows. First, a suitable organic solvent, solvent, etc. are added to and mixed with raw material powders such as alumina (Al2O3) or silica (SiO2), calcia (CaO), magnesia (MgO), etc., and this is made into a mud-like form. To make granules. Next, this granule is obtained by using a known dry press method to obtain a molded body having the shape having the upper surface 21, the lower surface 22, the inner surface 23, and the stepped portion 2a as described above. Thereafter, the frame body 2 is manufactured by firing the molded body at a temperature of, for example, about 1600 (° C.). The formation of the recess 24a of the frame body 2 may be performed by a press die when, for example, a molded body before firing is produced, or may be performed by laser processing or slicing processing after firing.

The translucent member 3 is a plate-like body made of a translucent material, that is, a material that transmits light. The light here is light that is emitted or received by an optical element mounted on the optical device 100 in which the optical device lid 10 is used, and is mainly visible light. The translucent member 3 is a plate material made of a transparent glass material such as soda glass or borosilicate glass, and is preferably a glass material having a high light transmittance. In general, the translucent member 3 such as glass has lower rigidity and lower tensile strength than the frame 2 made of ceramics. Therefore, the mutual thermal expansion coefficient can be made an approximate value so that the translucent member 3 is not destroyed by the thermal stress applied to the joint between the translucent member 3 and the frame 2. For example, if the frame member 1 is an alumina sintered body (thermal expansion coefficient is about 7.2 × 10 ⁻⁶ / ° C.), the translucent member 3 is, for example, BK7 (manufactured by HOYA, having a thermal expansion coefficient). The difference in coefficient of thermal expansion between each other is 0, such as a glass material such as about 7.5 × 10 ⁻⁶ / ° C.) or D263 (manufactured by Schott, thermal expansion coefficient is about 7.2 × 10 ⁻⁶ / ° C.). The thing which becomes below 5 * 10 < ^-6 > / degreeC can be used.

  For example, the translucent member 3 is formed by cutting a large plate made of the above translucent material into a rectangular plate having a predetermined size (hereinafter also referred to as a rectangular plate). Produced. For example, a groove can be formed on the main surface of a large plate by laser or dicing, and mechanical stress or thermal stress can be applied to the groove. The side surface of the rectangular plate obtained by this cutting is substantially flat. Although it may be used as the translucent member 3 as it is, the corners are perpendicular to each other by the principal surfaces and the side surfaces of the rectangular plate body, and the corners are ground by polishing at an angle of 45 ° with respect to the right angle between the side surfaces. Is formed, it is difficult for chipping to occur at the corners, and even when stress is applied to the translucent member 3, it is difficult to break.

  The frame member 1 and the frame body 2 are joined by a first joining material 4, and the frame body 2 and the translucent member 3 are joined by a second joining material 5. Since the joining of the frame member 1 and the frame body 2 and the joining of the frame body 2 and the translucent member 3 are not performed at the same time, the joining material used for the previous joining is melted in the later joining. In order to prevent this, the first bonding material 4 and the second bonding material 5 have different melting points. Further, when the optical device lid 10 (the frame member 1) and the frame portion 62 of the package 6 are bonded, the first bonding material 4 is closer to the bonding portion between the frame member 1 and the frame portion 62. The first bonding material 4 can have higher heat resistance (melting point). Therefore, for example, a metal brazing material can be used as the first bonding material 4 and a low melting point glass can be used as the second bonding material 5.

The first bonding material 4 is made of a metal brazing material using a silver-copper (Ag—Cu) alloy or an active metal brazing material obtained by adding an active metal such as titanium (Ti) to a silver-copper alloy, and the frame member 1 and the frame body. It plays the role which joins 2 airtightly. The active metal brazing material can directly join the frame member 1 made of metal and the frame body 2 made of ceramics. When a metal brazing material is used, a metal film such as a metallized layer is provided so that the metal brazing material is wetted and joined to the upper surface of the frame 2. In this case, since the first bonding material 4 does not wet and spread beyond the metal film, the position of the bonding portion between the frame member 1 and the frame body 2 can be set more accurately.

The second bonding material 5 plays a role of airtightly bonding the frame body 2 and the translucent member 3. As the second bonding material 5, a material made of a material having a thermal expansion coefficient comparable to that of the frame body 2 or the translucent member 3 can be used. For example, as the second bonding material 5, low melting point glass having a thermal expansion coefficient comparable to that of the frame body 2 or the translucent member 3 can be used. As a result, the thermal stress applied to the second bonding material 5 becomes relatively small and is bonded to the stepped portion 2a of the frame body 2 with high bonding strength. When the thermal expansion coefficient of the low melting point glass is as large as about 10 × 10 ⁻⁶ / ° C. or more, a low thermal expansion material such as cordierite compound is added as a filler, and the thermal expansion coefficient is 4 to 8 × 10 6. It can be set to about ⁻⁶ / ° C. or less.

  The low-melting glass used as the second bonding material 5 may be, for example, a conventionally known lead-based low-melting glass, but is preferably made of lead-free glass because of its influence on the environment. Examples of the lead-free low-melting glass include bismuth-based lead-free glass that can be bonded at a low temperature of about 450 (° C.) and vanadium pentoxide-based lead-free glass that can be bonded at a low temperature of about 400 (° C.).

  For example, when the active metal brazing material is used as the first bonding material 4, the frame member 1 and the frame body 2 can be bonded as follows. First, an active metal brazing paste is applied to at least one of the joint surfaces of the frame member 1 and the frame body 2 in a predetermined pattern, for example, with a thickness of 30 μm to 50 μm using known screen printing or the like. The active metal brazing paste is composed of silver, copper powder, silver-copper alloy powder, or silver brazing material (for example, silver: 72% by mass-copper: 28% by mass) powder composed of titanium, An active metal such as hafnium, zirconium or a hydride thereof is added to and mixed with 2 to 5% by mass of the silver brazing material, an appropriate binder and a solvent such as an organic solvent are added and mixed, and then kneaded. be able to. Then, the frame member 1 is placed on the frame body 2 so as to have a predetermined structure, and a load is applied to the frame member 1 in a non-oxidizing atmosphere such as a hydrogen gas atmosphere or a nitrogen gas atmosphere in a vacuum. The frame member 1 and the frame body 2 are joined by the first joining material 4 by heating at 780 ° C. to 900 ° C. for 10 minutes to 120 minutes to melt the brazing material.

  When forming a plating film on the surface of the frame member 1, the frame member 1 and the frame body 2 are preferably bonded after the first bonding material 4. The plating film is made of a metal plating film such as Ni (nickel) or Au (gold), and serves to improve the bondability between the frame member 1 and the package 6 or to improve the corrosion resistance of the frame member 1. Fulfill. When nickel plating is applied, as described above, if the Ni plating film contains Co or Cr, an alloy of Ni and Co or an alloy of Ni and Cr is formed, and the melting point of the plating film is about the same. The electrical resistance increases as it is. Therefore, when the optical device lid 10 and the package 6 are joined, heating in the vicinity of the surface of the frame member 1 is possible, and the amount of heat transferred to the second joining material 5 is further reduced, and airtight reliability is improved. Further improve. In addition, when the Ni plating film containing B (nickel plating film containing boron) is used, boron contained in the nickel plating forms a very thin glassy material on the surface and works to protect nickel from oxidation. The heat resistance of the nickel plating film is increased. Therefore, it is difficult to oxidize even when heat is applied at the time of joining the frame body 2 and the translucent member 3, and the influence on the joining performance between the optical device lid body 10 and the package 6 is made small. Can do.

The frame 2 and the translucent member 3 are bonded to each other by the second bonding material 5 such as a low melting point glass as follows, for example. First, using a known dispensing method or the like, a glass paste serving as a second bonding material in the stepped portion 2a of the frame body 2 to which the frame member 1 is bonded has a thickness of, for example, 80 (μm) to 200 (μm). Apply. The glass paste can be manufactured by adding and mixing the above glass powder, a binder, and a solvent such as an organic solvent, and kneading. After drying the glass paste, the translucent member 3 is placed in the stepped portion 2a and heated to, for example, 500 ° C. to 550 ° C. higher than the melting point of the glass, whereby the outer edge and side surfaces of the upper surface of the translucent member 3 Is joined to the stepped portion 2 a of the frame 2 by the second joining material 5. Thus, the optical device lid body 10 including the frame member 1, the frame body 2, and the translucent member 3 is obtained.

  The outer peripheral edge portion and the side surface of the upper surface of the translucent member 3 are bonded via the second bonding material 5 in the stepped portion 2 a on the inner surface 23 side of the lower surface 22 of the frame body 2. Due to the high rigidity of the frame body 2, it becomes difficult for thermal stress due to heat that the frame member 1 is joined to the frame portion 62 by seam weld or the like to be transmitted to the translucent member 3. Even when the thermal expansion coefficients of the members 3 are different, the airtight reliability can be maintained.

  By adjusting conditions such as the amount of glass paste applied, heating temperature, and heating time, the second bonding material 5 can be prevented from protruding beyond the inner side surface 23.

  In the optical device 100, the optical element 7 is mounted on the base 61 of the package 6, the optical element 7 and the terminal 63 of the package 6 are electrically connected by a bonding wire 8, and the optical device lid 10 frame member 1. The optical element 7 can be manufactured by hermetically sealing the lower surface 11 of the outer edge portion 1a of the frame member and the upper surface of the frame portion 62 by, for example, seam welding.

  The optical element 7 is a light emitting element such as a laser diode or LED, and serves as a light source such as a projector or a headlight of an automobile. In the example shown in FIGS. 5 and 6, three optical elements 7 are mounted. For example, the emission colors can be different such as R (red), G (green), and B (blue). As the optical element 7 other than the light emitting element, an imaging element such as a CCD and a CMOS, a MEMS element such as an optical switch and a mirror device, and the like can be used. The optical device lid 10 is more effective when the optical element 7 emits light at a wide angle or receives light at a wide angle. The number of optical elements 7 to be mounted, and the color and type of light may be in accordance with the optical device. The optical element 7 is fixed on the base 61 with a metallic bonding material such as Au—Sn or a resin adhesive.

  The bonding wire 8 that connects the optical element 7 and the terminal 63 can be a gold or aluminum wire.

By using copper (thermal expansion coefficient: about 16.7 × 10 ⁻⁶ / ° C.) having a high thermal conductivity or a copper alloy material as the substrate 61 of the package 6, the heat generated from the high-power optical element 7 is effective. Can be discharged to the outside. As in the example shown in FIGS. 5 and 6, when the base 61 has a thick portion where the optical element 7 is mounted, heat is more effectively discharged.

Further, the frame portion 62 of the package 6 does not need to have a thermal conductivity as high as that of the base 61, and a metal member having high rigidity, for example, a metal member such as SPC (Steel Plate Cold) can be used. The thermal expansion coefficient of copper is about 16.7 × 10 ⁻⁶ / ° C., and the thermal expansion coefficient of SPC is about 11.7 × 10 ⁻⁶ / ° C., so that the frame member 1 and the frame body of the lid 10 for an optical device are used. Larger than 2. For this reason, when the package 6 and the optical device lid 10 are seam welded, stress is applied to the joint. However, by using the optical device lid 10 having the above structure, reliability such as a temperature cycle can be obtained. The optical device 100 is excellent in performance.

The terminal 63 of the package 6 is made of a metal material such as 42 alloy (FeNi42 alloy), FeNi29Co17 alloy, etc., and has a rod-like shape with a circular cross section, for corrosion prevention and bondability of connecting members such as the bonding wire 8. Furthermore, a plating film such as nickel and gold can be provided on the surface.

  The sealing material 64 of the package 6 is insulative, and for example, glass can be used. The glass used for said 2nd joining material 5 can also be used, and other than that, for example, the high temperature glass with a low dielectric constant containing many silicas can also be used.

  The present invention is not limited to the embodiments described above, and various modifications and improvements can be made without departing from the scope of the present invention. For example, a frame-shaped copper plate having the same dimensions as the first bonding material 4 is bonded to the frame member 1 with a bonding material such as silver brazing, and the copper plate portion and the frame body 2 are bonded with the first bonding material 4 made of active silver brazing. You may join. In this case, since a soft copper plate is interposed at the joint portion between the frame member 1 and the frame body 2, the stress can be further relaxed.

  Further, the structure of the package 6 is not limited to the above example. For example, the base body 61 and the frame portion 62 of the package 6 may be made of a metal other than those described above, or ceramics may be used. In that case, the frame member 1 can be joined to the upper surface of the frame portion 62 by seam welds, for example, by joining a metal plate. Further, the terminal 63 is provided with one through hole in the frame portion 62 with respect to one terminal 63 and fixed with the sealing material 64, whereas the plurality of terminals 63 are formed with one sealing material 64. It can also be fixed together in the through hole.

DESCRIPTION OF SYMBOLS 1 ... Frame member 1a ... Outer edge part 11 (of frame member) ... Upper surface 12 (of frame member) Lower surface 13 ... (of frame member) Inner side surface 2 (of frame member) ..Frame body 2a ... Step 21 ... Upper surface 22 (of frame body) ... Lower surface 23 (of frame body) Inner side surface 24 ... (of frame body) Step surface 24a ... Concave portion 25 ... Step side surface 3 (of frame) Translucent member 31 ... Upper surface of translucent member 32 ... Lower surface of translucent member 33 ... Side 4 (translucent member) 4 ... first bonding material 5 ... second bonding material 6 ... package 61 ... base 62 ... frame portion 63 ... terminal 64 ... Sealing material 7 ... Optical element 8 ... Bonding wire 10 ... Lid for optical device 100 ... Optical device

Claims (8)

A frame member made of a metal plate, a frame body having a stepped portion that is smaller in plan view than the frame member and cut out from the lower surface to the inner surface, and a plate-like translucent member,
The frame member has an outer edge projecting from the outer edge of the frame body and joined to the upper surface of the frame body with a first bonding material, and the translucent member has an outer edge portion and a side surface on the upper surface of the step of the frame body. A lid for an optical device that is bonded to the portion with a second bonding material.   The lid for an optical device according to claim 1, wherein the frame member and the frame body are joined outside the stepped portion.   The optical device lid according to claim 1, wherein a surface of the frame member is covered with a Ni plating film containing Co or Cr.   4. The optical device lid according to claim 1, wherein a surface of the frame member is covered with a Ni plating film containing B. 5.   5. The lid for an optical device according to claim 1, wherein the second bonding material is positioned outside the inner side surface of the frame body.   The optical device lid according to any one of claims 1 to 5, wherein the frame body has a concave portion on a step surface of the step portion, and the second bonding material enters the concave portion.   The optical device lid according to any one of claims 1 to 6, wherein an optical film is provided on at least one of the upper surface and the lower surface of the translucent member.   An optical device comprising the optical device lid according to any one of claims 1 to 7, a package, and an optical element mounted on the package.

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