JP6629660B2 - Ceramic package and manufacturing method thereof - Google Patents

Description

  The present invention relates to a ceramic package and a method for manufacturing the same.

  In some ceramic packages, brazing is performed to join metal materials. For example, in Patent Document 1 below, a terminal is brazed and joined to a lead connection portion formed on a ceramic substrate with a silver solder. Other ceramic packages include a metal seal ring brazed to a ceramic substrate. The seal ring is a seal member for hermetically joining a metal lid, which is a metal lid member that covers an element mounted on the ceramic substrate, and is brazed to a metallized layer previously formed on the ceramic substrate. Joined.

Japanese Patent Publication No. 7-63083

  The inventor of the present invention, while repeating research on ceramic packages, has found that in a high-temperature and high-humidity environment, some metal components may be eluted at a joint portion of a brazed seal member. I found it. As described above, in the ceramic package, there is still room for improvement with respect to the technique for suppressing the deterioration of the brazed joint.

  The present invention has been made to solve the above-described problem, and can be realized as the following embodiments.

[1] According to a first embodiment of the present invention, a ceramic package is provided. This ceramic package may include a ceramic substrate, a metallization layer, a plating layer, a brazing material layer, and a sealing member. The ceramic substrate may have a pair of surfaces. The metallized layer may be disposed along a periphery of a predetermined region on the surface of the ceramic substrate. The plating layer may be disposed on the metallized layer. The brazing material layer may be disposed on the metallized layer with the plating layer interposed therebetween. The seal member may be joined on the metallized layer via the brazing material layer. At least one of the outer peripheral edge and the inner peripheral edge of the brazing material layer, the end of the brazing material layer is located outside the lower region of the sealing member and is located at a distance of 0.1 mm from the end of the metallized layer. It may be at a position closer to the seal member side by at least 02 mm. According to the ceramic package of this aspect, elution of the metal component at the joint portion of the seal member is suppressed. Therefore, deterioration of electrical characteristics such as a decrease in insulating properties of the ceramic package, and deterioration in appearance are suppressed.

[2] In the ceramic package according to the above aspect, the thickness of the plating layer may be 1.5 μm or more and 5 μm or less at least at a portion sandwiched between the metallization layer and the brazing material layer. According to the ceramic package of this aspect, the elution of the metal component from the joint portion of the seal member is further suppressed.

[3] In the ceramic package according to the above aspect, the plating layer is a first plating layer, and a second plating layer is further formed on the brazing material layer, and an outer periphery of the second plating layer is provided. At least one of a side end portion or an inner peripheral end portion is in contact with the first plating layer, and the thickness of the second plating layer is at least at a portion located on the brazing material layer. 0.5 μm or more and 5 μm or less. According to the ceramic package of this aspect, the elution of the metal component from the joint portion of the seal member is further suppressed.

[4] In the ceramic package according to the aspect described above, a cavity that opens in one direction is formed on the surface of the ceramic substrate by a wall that surrounds the region, and the metallized layer is a wall that surrounds the cavity. It may be formed on the upper end surface of the part. According to the ceramic package of this aspect, elution of the metal component from the joint portion of the seal member provided on the periphery of the opening of the cavity is suppressed.

[5] In the ceramic package according to the above aspect, at least one of the outer peripheral edge portion and the inner peripheral edge portion of the brazing material layer, the brazing material layer has a bottom surface of the seal member and a lower end of a side surface of the seal member. May be in contact with According to the ceramic package of this embodiment, the joining strength of the sealing member by the brazing material layer is increased.

[6] In the ceramic package according to the above aspect, at least one of the outer peripheral edge and the inner peripheral edge of the brazing material layer, which appears in a cross section along the laminating direction of the brazing material layer and the metallized layer, has a contour line. The seal member may have an end portion that extends downward from a side surface of the seal member and forms a downwardly convex curve. According to the ceramic package of this embodiment, the joining strength of the sealing member by the brazing material layer is further increased.

[7] According to a second embodiment of the present invention, a method for manufacturing a ceramic package is provided. The manufacturing method of this embodiment may include a metallized layer forming step, a first plating step, a brazing material layer forming step, a joining step, a second plating step, and a heating step. The metallization layer forming step may be a step of forming a metallization layer along an outer periphery of a predetermined region on the surface of the ceramic substrate having a pair of surfaces. The first plating step may be a step of forming a first plating layer on the metallized layer. The joining step may be a step in which the sealing member is joined by brazing to the metallized layer via the brazing material layer. The second plating step may be a step in which a second plating layer is further formed on the brazing material layer after the joining step. The heating step may be a step in which the ceramic substrate is heated at a temperature of 500 ° C. or more after the second plating step. According to the ceramic package manufactured by the manufacturing method of this aspect, elution of the metal component from the joint portion of the seal member is suppressed.

[8] The manufacturing method according to the above aspect, further comprising, before the second plating step, at least one of an outer peripheral end and an inner peripheral end of the brazing material layer has an outer peripheral end or an inner peripheral end of the metallized layer. An end adjustment step may be provided in which an end of the brazing material layer is processed so as to be 0.02 mm or more inside from the part. According to the ceramic package manufactured by the manufacturing method of this aspect, the elution of the metal component from the joint portion of the seal member is further suppressed.

  All of the plurality of components of each of the above-described embodiments of the present invention are not essential, and may solve some or all of the above-described problems, or may partially or wholly provide the effects described in this specification. In order to achieve the above, it is possible to appropriately change or delete some of the plurality of components, replace them with new components, and partially delete limited contents. In addition, in order to solve some or all of the above problems or to achieve some or all of the effects described in this specification, technical features included in one embodiment of the present invention described above are described. Some or all of the technical features included in other aspects of the present invention described above may be combined with some or all of the technical features to form an independent aspect of the present invention.

  The present invention can be realized in various forms other than the ceramic package and the method of manufacturing the same. For example, the present invention can be realized in the form of a ceramic package in which a metal lid is joined to a seal member, an apparatus used for manufacturing the ceramic package, a method of brazing and joining a metal member to a ceramic substrate, and the like.

FIG. 2 is a schematic perspective view illustrating a configuration of a ceramic package according to the first embodiment. FIG. 2 is a schematic cross-sectional view showing a configuration of a joint portion of a seal ring. FIG. 3 is a schematic cross-sectional view showing the configuration near the ends of a metallized layer and a brazing material layer. FIG. 4 is a process flowchart showing a manufacturing process of the ceramic package according to the first embodiment. FIG. 7 is a schematic cross-sectional view illustrating a configuration of a joint portion of a seal ring according to a second embodiment. FIG. 9 is a process flowchart showing a manufacturing process of the ceramic package according to the second embodiment. FIG. 9 is a schematic perspective view illustrating a configuration of a ceramic package according to a third embodiment. Explanatory drawing which shows the test result of the environmental test in Experimental example 1. Explanatory drawing which shows the test result of the environmental test in Experimental example 2.

Embodiments of the present invention will be described in the following order.
A. First embodiment
B. Second embodiment
C. Third embodiment
D. Experimental example
E. Modified example

A. First embodiment:
[Configuration of ceramic package]
FIG. 1 is a schematic perspective view showing a configuration of a ceramic package 10A according to the first embodiment of the present invention. FIG. 1 shows a metal lid 20 attached to the ceramic package 10A for convenience. Further, in FIG. 1, arrows X, Y, and Z indicating three directions orthogonal to each other are illustrated with reference to the ceramic package 10A. Arrow X indicates the direction along the short side of ceramic package 10A, arrow Y indicates the direction along the long side, and arrow Z indicates the direction along the thickness direction. Arrows X, Y, and Z are appropriately illustrated in each of the drawings referred to in this specification.

  The ceramic package 10A can mount electronic components such as a quartz oscillator, a semiconductor element, and a piezoelectric element inside. The ceramic package 10 </ b> A includes a substrate unit 11 and a seal ring 15. The substrate section 11 corresponds to a lower concept of the ceramic substrate in the present invention. In the present embodiment, the substrate unit 11 is formed of a substantially rectangular ceramic plate having a pair of surfaces 11a and 11b. As the ceramic constituting the substrate portion 11, for example, a high-temperature fired ceramic containing alumina as a main component or a low-temperature fired ceramic containing glass can be used. In the present specification, the “main component” means a component having a mass ratio of 50% or more in all components.

  On the first surface 11a of the substrate portion 11, a cavity 12 that forms a space for accommodating an electronic component (not shown) mounted on the ceramic package 10A is formed as a bottomed concave portion that opens in the direction of arrow Z. ing. In the present embodiment, the cavity 12 is surrounded by a ceramic side wall 14 formed along the outer periphery of the substrate 11, and has a substantially rectangular opening cross section. On the bottom surface 12b of the cavity 12, an electrode pad 13 to which an electronic component is connected is provided. The electrode pad 13 is made of, for example, a conductive material mainly containing tungsten (W) or molybdenum (Mo).

  On the second surface 11b of the substrate portion 11, a terminal portion for electrically connecting to a wiring of a circuit board on which the ceramic package 10A is mounted is formed (not shown). Further, a wiring pattern and a via electrode for connecting the electrode pad 13 and the terminal section are formed inside the substrate section 11 (not shown). The terminal portions, the wiring patterns, and the via electrodes are made of a conductive material containing W or Mo as a main component, for example, like the electrode pad 13.

  The seal ring 15 is a metal seal member arranged on the periphery of the opening of the cavity 12. In the present embodiment, the seal ring 15 has a rectangular frame shape in which a substantially rectangular through hole is provided at the center of a substantially rectangular plate member. The seal ring 15 is made of, for example, an alloy such as 42 Alloy or Kovar, and is manufactured by press working or casting. The lengths of the long side and the short side of the seal ring 15 correspond to the lengths of the long side and the short side of the substrate 11, and the seal ring 15 will be on the upper end surface 14 t of the side wall 14 surrounding the cavity 12. The seal ring 15 has a joint portion 16A formed at the periphery thereof. The joining method of the seal ring 15 and the configuration of the joining portion 16A will be described later.

  Before the ceramic package 10A is mounted on the circuit board, electronic components are accommodated and arranged in the cavity 12. Then, a metal lid 20 as a metal lid member is arranged so as to cover the entire opening of the cavity 12, and is seam-welded to the seal ring 15. The metal lid 20 is made of, for example, Kovar or stainless steel (SUS304). In the ceramic package 10A, the cavity 12 is hermetically sealed by the metal lid 20, and the mounted electronic components are protected.

  With reference to FIG. 2 and FIG. 3, the configuration of the joint 16A of the seal ring 15 in the ceramic package 10A will be described. FIG. 2 is a schematic cross-sectional view showing the configuration of the joint 16A of the seal ring 15. FIG. 2 shows a schematic cross section of the ceramic package 10A taken along the line AA shown in FIG. FIG. 3 is a schematic cross-sectional view showing the configuration near the ends 31t and 33t of the metallized layer 31 and the brazing material layer 33. FIG. 3 shows the region B shown in FIG. The region B is a region including the outer peripheral edge portion 18a of the brazing material layer 33. In the present embodiment, the outer peripheral edge 18a and the inner peripheral edge 18b of the brazing material layer 33 have the same configuration, and the following description of the outer peripheral edge 18a will be applied to the configuration of the inner peripheral edge 18b. The same is true. The cross sections shown in FIGS. 2 and 3 correspond to a cross section of the metallized layer 31 and the brazing material layer 33 along the laminating direction.

  In the ceramic package 10A, a metallized layer 31 is formed on the upper end surface 14t of the side wall portion 14 in the substrate portion 11. The seal ring 15 is joined to the metallized layer 31 via the brazing material layer 33. More specifically, it is as follows.

  The metallized layer 31 is a metal thin film layer, and contains, for example, W or Mo as a main component. The metallization layer 31 is formed so as to surround the periphery of the cavity 12, which is a mounting area for the electronic element, when the ceramic package 10A is viewed in a plan view, that is, when viewed in the direction of arrow Z. The surface of the metallized layer 31 is covered with a first plating layer 32. The first plating layer 32 has a function of increasing the wettability of the brazing material constituting the brazing material layer 33, and is formed of, for example, a nickel (Ni) plating layer.

  The brazing material layer 33 is a thin film layer of a brazing material, and is formed on the metallized layer 31 via the first plating layer 32. The brazing material layer 33 is formed of a brazing material whose main component is a metal that is electrochemically more noble than the metal that is the main component of the metallized layer 31. In the present embodiment, the brazing material layer 33 is formed of silver brazing mainly containing silver (Ag) which is more noble than W or Mo. The brazing material layer 33 is formed so as to surround the cavity 12 similarly to the metallized layer 31.

  In the ceramic package 10A, further, a second plating layer 34 is formed so as to cover the seal ring 15, the brazing material layer 33, and the first plating layer 32, and the second plating layer 34 is formed so as to cover the second plating layer 34. A third plating layer 35 is formed. The second plating layer 34 is formed of, for example, a Ni plating layer, like the first plating layer 32. The third plating layer 35 is made of, for example, a gold (Au) plating layer.

  In the ceramic package 10A of the present embodiment, both the inner peripheral edge 18b, which is the inner peripheral edge (the cavity 12 side) of the brazing material layer 33, and the outer peripheral edge 18a, which is the outer peripheral edge opposite to the inner peripheral edge 18b. The end 33t of the brazing material layer 33 is located outside the region below the seal ring 15. In FIG. 3, a boundary line between the inside and the outside of the lower region of the seal ring 15 is illustrated by a dashed line La. When brazing is performed in a state where the end 33t of the brazing material layer 33 is located in a region below the seal ring 15, a broken line is shown between the first plating layer 32 and the bottom surface 15t of the seal ring 15. There is a possibility that the curved surface MS of the meniscus of the brazing material layer 33 as described above is formed. When such a curved surface MS of the meniscus is formed, stress concentration tends to occur starting from the curved surface MS, and the bonding strength of the seal ring 15 by the brazing material layer 33 is reduced. On the other hand, in the ceramic package 10A of the present embodiment, as described above, the end 33t of the brazing material layer 33 is located outside the region below the seal ring 15, and the brazing material as described above is used. The formation of a meniscus at the end 33t of the layer 33 is suppressed. Therefore, a decrease in the joining strength of the seal ring 15 due to the brazing material layer 33 is suppressed.

  In the ceramic package 10A of this embodiment, the brazing material layer 33 is in contact with the bottom surface 15t of the seal ring 15 and the lower end of the side surface 15s at each of the outer peripheral edge 18a and the inner peripheral edge 18b. Thereby, the joining area between the brazing material layer 33 and the seal ring 15 is increased, and the joining strength of the seal ring 15 by the brazing material layer 33 is increased. In addition, each contour line OL of the outer peripheral edge portion 18a and the inner peripheral edge portion 18b of the brazing material layer 33 has an end portion OLf that forms a downwardly convex curve extending downward from the side surface 15s of the seal ring 15. have. By having such an end portion OLf, the stress generated in the brazing material layer 33 can be easily released outward, and high joining strength of the seal ring 15 by the brazing material layer 33 can be obtained. it can.

  Furthermore, in the ceramic package 10 </ b> A of the present embodiment, the ends 33 t of the outer peripheral edge 18 a and the inner peripheral edge 18 b of the brazing material layer 33 are both ends 31 t of the metallized layer 31 on the same side with respect to the seal ring 15. It is located further inside (on the side of the seal ring 15). As described above, in the ceramic package 10A of the present embodiment, the end 31t of the metallized layer 31 and the end 33t of the brazing material layer 33 are formed at positions separated from each other. The reason will be described later.

  It is desirable that the end-to-end distance ED, which is the distance between the end 31t of the metallized layer 31 and the end 33t of the brazing material layer 33, is 0.020 mm or more. The end-to-end distance ED is in contact with the end 31t of the metallized layer 31 and in contact with the first imaginary perpendicular line L1 perpendicularly intersecting the upper end surface 14t and the end 33t of the brazing material layer 33 and the upper end surface 14t. This corresponds to the distance between the second virtual perpendicular L2 that intersects perpendicularly. The end-to-end distance ED is positive when the second virtual perpendicular L2 is closer to the seal ring 15 than the first virtual perpendicular L1, and the second virtual perpendicular L2 is farther from the seal ring 15 than the first virtual perpendicular L1. It is negative when it is on the side.

  Further, in the present embodiment, the first plating layer 32 has a thickness of 1.5 μm or more and 5 μm or less. The second plating layer 34 has a thickness of 1.5 μm or more and 5 μm or less. In the present specification, the thickness of the first plating layer 32 means the thickness at a portion sandwiched between the metallization layer 31 and the brazing material layer 33, and the thickness of the second plating layer 34 is Means the thickness of the part located at. The reason why the first plating layer 32 and the second plating layer 34 have the above-described thickness will be described later.

[Ceramic package manufacturing process]
FIG. 4 is a process flowchart showing a manufacturing process of the ceramic package 10A. In step 1, the substrate section 11 on which the metallized layer 31 is formed is prepared. Specifically, first, a plurality of green sheets of the same size having a substantially rectangular shape are produced by forming a ceramic slurry containing alumina powder, a binder resin, a solvent, and the like into a sheet shape by a doctor blade method. Is done.

  For some of the green sheets, an unfired conductive paste containing Mo or W as a main component is used, and after firing, an unfired conductive paste for forming the electrode pads 13, terminal portions, wiring patterns, via electrodes, and the like is formed. Is formed. A substantially rectangular through-hole forming the cavity 12 is formed at the center of the remaining green sheet by punching.

  Next, a frame-shaped green sheet having a through-hole formed thereon is laminated on a flat green sheet having an unfired wiring portion formed thereon, and is pressed under a predetermined load to form a green sheet laminate constituting the substrate portion 11. The body is made. The green sheet laminate is fired at a predetermined firing temperature after a conductive paste containing Mo or W as a main component is applied to the periphery of the opening of the concave portion forming the cavity 12 by screen printing or the like. As a result, the substrate portion 11 having the metallized layer 31 formed around the cavity 12 is obtained. Step 1 corresponds to a lower concept of the metallized layer forming step in the present invention.

  In step 2, the first plating layer 32 is formed by the first plating process so as to cover the surface of the metallized layer 31. In the present embodiment, electrolytic nickel plating is performed as the first plating process. In the first plating process, the current value is adjusted so that the first plating layer 32 has a thickness of 1.5 μm or more and 5 μm or less. Step 2 corresponds to a subordinate concept of the first plating step in the present invention.

  In step 3, the brazing material layer 33 is formed by supplying the molten brazing material so as to spread over the entire surface of the first plating layer 32. Step 3 corresponds to a lower concept of the brazing material layer forming step in the present invention. In step 4, the seal ring 15 is arranged at a predetermined position on the brazing material layer 33 to solidify the brazing material layer 33. Thereby, the seal ring 15 is brazed to the substrate portion 11. Step 4 corresponds to a lower concept of the joining step in the present invention. In step 5, the end portion 33t of the brazing material layer 33 is adjusted by the etching process so as to be located inside the end portion 31t of the metallized layer 31. Step 5 corresponds to a lower concept of the end adjustment step in the present invention.

  In step 6, a second plating layer 34 is formed by the second plating process. In the present embodiment, electrolytic nickel plating is performed as the second plating process. Step 6 corresponds to a subordinate concept of the second plating step in the present invention. In step 7, a heat treatment of heating the entire substrate portion 11 on which the second plating layer 34 is formed at a temperature of about 500 to 100 ° C. in a reducing atmosphere is performed. By this heat treatment, the adhesion of the first plating layer 32 and the second plating layer 34 to the respective bases is enhanced. Step 7 corresponds to a lower concept of the heating step in the present invention. Further, in step 8, a third plating layer 35 is formed by a third plating process. Through the above steps, the ceramic package 10A is completed.

[About the effect of suppressing deterioration at the joint of the seal ring]
The inventor of the present invention has obtained the following knowledge during repeated studies on the joining portions that have been brazed. When the brazed joint is exposed for a long time in a high-temperature and high-humidity environment (for example, at a temperature of 60 ° C. or more and a relative humidity of 90% or more), a part of the metal component of the metallized layer is exposed to the outside. May be eluted. This is because the main component of the brazing material layer is more electrochemically noble than the main component of the metallizing layer, so that a local battery is formed using the metallizing layer and the brazing material layer as electrodes, and the electric driving force is applied to the battery. It is presumed that this is because the elution of the main component of the metallized layer is promoted. Such elution of the metal component in the ceramic package causes a decrease in electrical insulation such as a short circuit or leakage of current, and causes a deterioration in electrical characteristics of the electronic component packaged.

  As described above, in the ceramic package 10A of the present embodiment, the end 33t of the brazing material layer 33 is located inside the end 31t of the metallized layer 31, and the end 31t of the metallized layer 31 and the brazing material layer 33 are formed so as to be separated from the end 33t (FIG. 3). Therefore, formation of the above-described local battery between the metallized layer 31 and the brazing material layer 33 is suppressed, and the elution of the metal component from the metallized layer 31 is suppressed. In particular, in the ceramic package 10A of the present embodiment, since the distance ED between the ends is 0.020 mm or more, the elution of the metal component from the metallized layer 31 is suppressed at a higher level.

  In addition, in the ceramic package 10A of the present embodiment, the first plating layer 32 has a thickness of 1.5 μm or more at least at a portion between the metallization layer 31 and the brazing material layer 33. As a result, the metallized layer 31 and the brazing material layer 33 are separated from each other by the thickness of the first plating layer 32, so that the above-described formation of the local battery is further suppressed, and the elution of the metal component from the metallized layer 31 is prevented. Be suppressed. In addition, since the thickness of the first plating layer 32 at a portion between the metallization layer 31 and the brazing material layer 33 is 5 μm or less, the bonding property of the seal ring 15 due to the first plating layer 32 being too thick is reduced. Be suppressed.

  In the ceramic package 10 </ b> A of the present embodiment, the second plating layer 34 has a thickness of 1.5 μm or more at least at a position on the brazing material layer 33. Thereby, the sealing property of the brazing material layer 33 is enhanced, and the elution of the metal component from the brazing material layer 33 is suppressed. Further, since the metallized layer 31 and the third plated layer 35 are separated from each other by an amount corresponding to the thickness of the second plated layer 34, formation of a local battery using the metallized layer 31 and the third plated layer 35 as electrodes is suppressed. The elution of the metal component from the metallized layer 31 is suppressed. In addition, when the thickness of the second plating layer 34 is 5 μm or less, enlargement of the joint portion 16A is suppressed.

  In addition, in the ceramic package 10A of the present embodiment, the heat treatment is performed after the formation of the second plating layer 34, and the adhesion and sealing of the first plating layer 32 and the second plating layer 34 to the base are improved. Has been enhanced. Therefore, the elution of the metal component of the metallized layer 31 and the brazing material layer 33 is further suppressed.

  As described above, according to the ceramic package 10A in the first embodiment, even when the ceramic package 10A is exposed to a high-temperature and high-humidity environment for a long time, the occurrence of deterioration at the joint 16A of the seal ring 15 is suppressed. .

B. Second embodiment:
FIG. 5 is a schematic cross-sectional view illustrating a configuration of a joint portion 16B around the seal ring 15 in the second embodiment of the present invention. The configuration of the ceramic package 10B of the second embodiment is substantially the same as the configuration of the ceramic package 10A of the first embodiment, except that the configuration of the joining portion 16B of the seal ring 15 is different. In the joint portion 16B of the seal ring 15 in the second embodiment, the end 33t of the brazing material layer 33 is located at a position farther from the seal ring 15 than the end 31t of the metallized layer 31, and the upper end surface 14t of the side wall 14 is formed. Is in contact with The end of the second plating layer 34 is not in contact with the first plating layer 32. The outline OL of both the outer peripheral edge portion 18a and the inner peripheral edge portion 18b of the brazing material layer 33 has the same end portion OLf as described in the first embodiment.

  FIG. 6 is a process flowchart showing a manufacturing process of the ceramic package 10B in the second embodiment. The manufacturing process of the ceramic package 10B in the second embodiment is almost the same as the manufacturing process of the ceramic package 10A in the first embodiment, except that the step 5 is omitted. That is, in the second embodiment, the second plating layer 34 is formed without adjusting the position of the end of the brazing material layer 33 formed in Step 3 (Step 6). However, after the second plating layer 34 is formed, a heat treatment is performed as in the first embodiment (Step 7).

  As described above, in the ceramic package 10B of the second embodiment, the brazing material layer 33 extends to the region outside the metallized layer 31 at the joint portion 16B of the seal ring 15, and the end 31t is Is in contact with the upper end surface 14t of the second member. Even with such a configuration, since the heat treatment (Step 7 in FIG. 6) is performed in the manufacturing process, the adhesion and sealing of the first plating layer 32 and the second plating layer 34 to the base are improved. Have been. Therefore, the elution of the metal component from the metallized layer 31 and the brazing material layer 33 is suppressed, and the deterioration of the joint portion 16B in a high-temperature and high-humidity environment is suppressed.

C. Third embodiment:
FIG. 7 is a schematic perspective view illustrating a configuration of a ceramic package 10C according to the third embodiment. The configuration of the ceramic package 10C of the third embodiment is almost the same as the ceramic package 10A of the first embodiment except that the side wall 14 is not provided on the substrate 11C. The substrate portion 11C of the third embodiment is formed of a substantially rectangular flat ceramic plate and has no concave portion. In the ceramic package 10C of the third embodiment, the cavity 12 is formed in the frame of the seal ring 15, and the seal ring 15 forms the side wall surrounding the cavity 12.

  In the ceramic package 10C of the third embodiment, a seal ring similar to that described in the first embodiment is formed on the first surface 11a of the substrate portion 11C so as to surround the area where the electronic component is mounted. Fifteen joining parts 16A are formed. Even in the case of the ceramic package 10C of the third embodiment, similarly to the case of the ceramic package 10A of the first embodiment, the occurrence of deterioration at the joint 16A of the seal ring 15 is suppressed. In addition, with the ceramic package 10C of the third embodiment, various functions and effects similar to those described in the first embodiment can be obtained.

D. Experimental example:
D1. Experimental example 1
FIG. 8 is an explanatory diagram illustrating test results of an environmental test in Experimental Example 1. In Experimental Example 1, a constant temperature and humidity test (HHT) was performed on each of the samples S10 to S17 of the ceramic package 10A of the first embodiment. Each of the samples S10 to S17 was manufactured to have substantially the same configuration except that the end-to-end distances ED (FIG. 3) were different from each other. The main constituent materials of each of the samples S10 to S17 are as follows.
<Main constituent materials of each sample S10 to S17>
・ Main component of metallized layer: W
・ Main component of brazing material layer: Ag
-Main component of the first plating layer and the second plating layer: Ni
・ Main component of third plating layer: Au

Twenty samples of each of S10 to S17 were prepared, and a constant temperature and humidity test was performed on each of the samples under the following conditions.
<Test conditions for temperature and humidity test>
Temperature 60 ° C, relative humidity 90% RH

  The table in FIG. 8 shows that, for each of the samples S10 to S17, even after a lapse of a predetermined time (70 hours, 216 hours, 312 hours, 480 hours, 1056 hours) from the start of the test, even a slight elution of W on the appearance is observed. The number of observations is shown. In samples S10 to S13 in which the end-to-end distance ED was smaller than 0.020 mm, elution of W was observed 312 hours or 480 hours after the start of the test. On the other hand, in any of the samples S14 to S17 having the end-to-end distance ED of 0.020 mm or more, no elution of W was observed during the test. From this, it can be seen that in order to suppress the elution of W from the metallized layer, it is desirable that the end-to-end distance ED is 0.020 mm or more. In addition, since the distance ED between ends of the sample S14 is 0.024 mm, it is more preferable that the distance ED between ends is 0.024 mm or more.

D2. Experimental example 2
FIG. 9 is an explanatory diagram showing test results of an environmental test in Experimental Example 2. In Experimental Example 2, a constant temperature and humidity test was performed on various samples S20 to S25 described below. The outline of each of the samples S20 to S25 is as follows.
-Sample S20: has the same configuration as the ceramic package 10B described in the second embodiment, the thickness of the first plating layer 32 is 1.2 µm, and the thickness of the second plating layer 34 is 2.5 µm. is there. However, in the manufacturing process, the heat treatment in Step 7 is not performed.
Sample S21: has the same configuration as sample S20 except that the thickness of first plating layer 32 is 1.7 μm.
Sample S22: has the same configuration as sample S20 except that the thickness of the second plating layer 34 is 4.0 μm.
Sample S23: In the manufacturing process, it has the same configuration as Sample S21 except that the heat treatment in Step 7 was performed.
-Sample S24: has the same configuration as the ceramic package 10A described in the first embodiment, the thickness of the first plating layer 32 is 1.2 µm, and the thickness of the second plating layer 34 is 2.5 µm. is there. The distance ED between the ends is 0.024 mm. However, in the manufacturing process, the heat treatment in Step 7 is not performed.
Sample S25: In the manufacturing process, it has the same configuration as Sample S24 except that the heat treatment in Step 7 was performed.

The main constituent materials of each of the samples S20 to S25 are as follows.
<Main constituent materials of each sample S20 to S25>
・ Main component of metallized layer: W
・ Main component of brazing material layer: Ag
-Main component of the first plating layer and the second plating layer: Ni
・ Main component of third plating layer: Au

Twenty samples of each of the samples S20 to S25 were produced, and a constant temperature and humidity test was performed on each of the samples under the following conditions. In Experimental Example 2, the environmental humidity was higher than in the constant temperature / humidity test described with reference to FIG. 8, and the test time was shortened accordingly.
<Test conditions for temperature and humidity test>
Temperature 60 ° C, relative humidity 93% RH

  In the right-hand column of the table in FIG. 9, for each sample S20 to S25, after the prescribed time (75 hours, 480 hours, and 1000 hours) has elapsed from the start of the test, W grows into a black foreign matter-shaped mass. The number of those in which the remarkable remarkable elution of W was observed is shown. The following can be seen from the table of FIG.

  Comparing the sample S20 with the sample S21, it is understood that the elution of W is suppressed in the sample S20 in which the thickness of the first plating layer 32 is larger. Comparing the sample S20 and the sample S22, it can be seen that the elution of W is suppressed in the sample S22 in which the thickness of the second plating layer 34 is larger. As described above, as the thickness of the first plating layer 32 and the second plating layer 34 increases, the elution of metal components from the metallized layer can be suppressed. Further, it is desirable that the thickness of the first plating layer 32 and the second plating layer 34 is at least 1.2 μm or more, and in particular, the thickness of the second plating layer 34 is 2.5 μm or more. desirable.

  When the sample S20 is compared with the sample S23, the elution of W is suppressed in the sample S23 subjected to the heat treatment in the step 7. Further, in each of the samples S24 and S25, the heat treatment in the step 7 is performed, and the elution of W is suppressed. From these results, it can be seen that the heat treatment after the second plating treatment suppresses the elution of the metal component from the metallized layer.

  Both the sample S24 and the sample S25 have the same configuration as the ceramic package 10A of the first embodiment, and the distance ED between the ends is 0.024 mm. As described above, if the end 33t of the brazing material layer 33 is located inside the end 31t of the metallized layer 31 and the distance ED between the ends is 0.024 mm, the elution of the metal component from the metallized layer is prevented. It can be seen that it can be suppressed at a high level.

  As described above, based on the results of Experimental Examples 1 and 2, if the joints 16A and 16B described in the above embodiments were used for a long period of time in a high-temperature and high-humidity environment, the deterioration would occur. Is suppressed.

E. Modification:
E1. Modification 1
In the first embodiment, in both the outer peripheral edge 18a and the inner peripheral edge 18b of the brazing material layer 33, the end 33t is located inside the end 31t of the metallized layer 31. On the other hand, the end 33t of the brazing material layer 33 only needs to be located inside the end 31t of the metallized layer 31 on at least one of the outer peripheral edge 18a and the inner peripheral edge 18b. Even with such a configuration, the bonding strength can be increased on the side where the end 33t of the brazing material layer 33 is located inside the end 31t of the metallized layer 31.

E2. Modified example 2:
In the manufacturing process of the first embodiment, after the second plating layer 34 is formed in the process 6, a heat treatment is performed in the process 7 (FIG. 4). On the other hand, in the manufacturing process of the first embodiment, the heat treatment in step 7 may be omitted. Even in this case, since the position of the end 33t of the brazing material layer 33 is adjusted in step 5, the elution of the metal component from the metallized layer 31 is suppressed to a considerable extent.

E3. Modification 3:
In the ceramic packages 10 </ b> A to 10 </ b> C of the above embodiments, a second plating layer 34 and a third plating layer 35 are formed in addition to the first plating layer 32. On the other hand, in the ceramic packages 10A and 10C of the first and third embodiments having the joint portion 16A, both the second plating layer 34 and the third plating layer 35 may be omitted, or the third and third plating layers 35 and 35 may be omitted. Only the plating layer 35 may be omitted. Further, in the ceramic package 10B of the second embodiment having the joint portion 16B, the third plating layer 35 may be omitted.

E4. Modification Example 4:
In step 5 of each of the above embodiments, the position of the end 33t of the brazing material layer 33 is adjusted by etching. On the other hand, in step 5, the position of the end 33t of the brazing material layer 33 may be adjusted by a process other than the etching process. For example, the position of the end 33t of the brazing material layer 33 may be adjusted by cutting or polishing.

E5. Modification 5:
The ceramic package 10C according to the third embodiment has the same joining portion 16A as that described in the first embodiment. On the other hand, the ceramic package 10C may have a joint 16B formed by the same manufacturing process as that described in the second embodiment, instead of the joint 16A of the first embodiment.

E6. Modification 6:
In the above-described first and third embodiments, the end 33t of the brazing material layer 33 is located outside the region below the seal ring 15 at both the outer peripheral edge 18a and the inner peripheral edge 18b. . On the other hand, the end portion 33t of the brazing material layer 33 only needs to be located outside the region below the seal ring 15 on at least one of the outer peripheral edge portion 18a and the inner peripheral edge portion 18b. Even in such a configuration, in the region where the end portion 33t of the brazing material layer 33 is located outside the region below the seal ring 15, the joining strength of the seal ring 15 by the brazing material layer 33 is not significantly increased. Can be.

E7. Modification 7:
In each of the above embodiments, the brazing material layer 33 is in contact with the bottom surface 15t of the seal ring 15 and the lower end of the side surface 15s at both the outer peripheral edge 18a and the inner peripheral edge 18b. On the other hand, the brazing material layer 33 may not be in contact with the bottom surface 15t of the seal ring 15 and the lower end of the side surface 15s at both the outer peripheral edge 18a and the inner peripheral edge 18b. The brazing material layer 33 may have a configuration in which at least one of the outer peripheral edge portion 18a and the inner peripheral edge portion 18b is in contact with the bottom surface 15t of the seal ring 15 and the lower end of the side surface 15s. Even with such a configuration, the joining strength of the seal ring 15 can be increased. Further, in each of the above embodiments, the outline OL of both the outer peripheral edge portion 18a and the inner peripheral edge portion 18b of the brazing material layer 33 appearing in a cross section along the laminating direction of the brazing material layer 33 and the metallized layer 31 is an end portion. It has OLf. On the other hand, only the outline OL of at least one of the outer peripheral edge 18a and the inner peripheral edge 18b of the brazing material layer 33 may have the end portion OLf. Even with such a configuration, the joining strength of the seal ring 15 can be further increased.

  The present invention is not limited to the above-described embodiments, examples, and modifications, and can be implemented with various configurations without departing from the spirit of the invention. For example, the technical features in the embodiments, examples, and modifications corresponding to the technical features in each embodiment described in the Summary of the Invention section are for solving some or all of the above-described problems, or In order to achieve some or all of the above-described effects, replacement and combination can be appropriately performed. If the technical features are not described as essential in this specification, they can be deleted as appropriate.

10A to 10C Ceramic packages 11, 11C Substrate 11a First surface 11b Second surface 12 Cavity 12b Bottom 13 Electrode pad 14 Side wall 14t Top surface 15 Seal rings 16A, 16B Joining area 18a Outer edge 18b Inner edge 20 Metal lid 31 Metallized layer 31t End 32 First plating layer 33 Brazing material layer 33t End 34 Second plating layer 35 Third plating layer

Claims (7)

A ceramic substrate having a pair of surfaces,
A metallized layer arranged along the outer periphery of a predetermined region on the surface of the ceramic substrate,
A plating layer disposed on the metallization layer,
A brazing material layer disposed on the metallized layer with the plating layer interposed therebetween,
Via the brazing material layer, a sealing member joined on the metallized layer,
In a ceramic package comprising
Oite the outer periphery and the inner periphery of the brazing material layer, the ends of the brazing material layer is an outer position of the lower region of the sealing member, from an end portion of the metallization layer, 0.02 mm As described above, the ceramic package is located at the position on the seal member side. The ceramic package according to claim 1,
A ceramic package, wherein the thickness of the plating layer is at least 1.5 μm and at most 5 μm at a portion sandwiched between the metallization layer and the brazing material layer. The ceramic package according to claim 1 or 2,
The plating layer is a first plating layer,
A second plating layer is further formed on the brazing material layer,
At least one of the outer peripheral end or the inner peripheral end of the second plating layer is in contact with the first plating layer,
A ceramic package, wherein the thickness of the second plating layer is at least 1.5 μm and at most 5 μm at a portion located on the brazing material layer. The ceramic package according to any one of claims 1 to 3,
On the surface of the ceramic substrate, a cavity that opens in one direction is formed by a wall surrounding the region,
The ceramic package, wherein the metallized layer is formed on an upper end surface of the wall surrounding the cavity. The ceramic package according to any one of claims 1 to 4, wherein
It said outer peripheral edge and Oite to the inner peripheral edge portion of the brazing material layer, wherein the brazing material layer has a bottom surface of the sealing member, and the lower end of the side surface of the sealing member, to have contact with the ceramic package. The ceramic package according to claim 5,
The outer periphery and the inner periphery of the contour line of the brazing material layer that appear in cross-section along the stacking direction of the brazing material layer and the metallization layer extends downward from the side surface of the sealing member A ceramic package having an end portion forming a downward convex curve. In a method of manufacturing a ceramic package including a ceramic substrate having a pair of surfaces,
Forming a metallized layer along the outer periphery of a predetermined region on the surface of the ceramic substrate,
A first plating step of forming a first plating layer on the metallization layer;
A brazing material layer forming step of forming a brazing material layer on the metallized layer via the first plating layer;
A bonding step of brazing the sealing member to the metallized layer via the brazing material layer,
A second plating step of forming a second plating layer on the brazing material layer after the joining step;
A heating step of heating the ceramic substrate at a temperature of 500 ° C. or higher after the second plating step;
And ,
Before the second plating step, the outer peripheral edge and the inner peripheral edge of the brazing material layer are located at least 0.02 mm from the outer peripheral edge or the inner peripheral edge of the metallized layer. A manufacturing method comprising an end adjusting step of processing an end of the brazing material layer .

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