JP2007250680A - Electronic component storing package and manufacturing method of sealing ring used therefore - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a sealing ring, with which a small electronic component storing package can easily be formed for storing an electronic component with high hermeticity. <P>SOLUTION: The package is provided with a wiring board 10, the sealing ring 20 fixed onto the wiring board with soft wax 12, and a lid body 25 fixed onto the sealing ring. The electronic component 35 is mounted on the wiring board in electronic component storing space RS demarcated by the wiring board and the sealing ring. For forming the electronic component storing package 30 where the lid body is welded to the sealing ring, at least an upper face, and an upper part of an outer face of the sealing ring are formed with a first coat 16; and at least a lower face, a lower part of the outer face, and a lower part of an inner face of the sealing ring are formed with a second coat. Material quality of the first coat and the second coat is selected so that wettability of soft wax in the second coat becomes higher than that in the first coat. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electronic component housing package for hermetically housing an electronic component mounted on a wiring board, and a method for manufacturing a seal ring used in the electronic component housing package.

  As a method for protecting electronic components such as semiconductor elements and piezoelectric vibration elements mounted on a wiring board from moisture, dust, etc., and preventing performance degradation and malfunction of the electronic components, the electronic components are packaged in an electronic component housing package. There is a method of housing and modularizing.

  Various electronic component storage packages used in this method are known, but as an electronic component storage package for storing an electronic component equipped with a high-frequency circuit, heat dissipation and electromagnetic shielding properties are considered. For example, as described in Patent Documents 1 to 3, there is an electronic component housing package of a type including a ceramic wiring board, a seal ring made of an inorganic conductive material, and a lid made of an inorganic conductive material. Often used.

  In this type of electronic component housing package, a seal ring is fixed on a ceramic wiring substrate, and the electronic component is mounted on the ceramic wiring substrate in an electronic component housing space defined by the wiring substrate and the seal ring. Since the upper end of the electronic component receiving space is open, after mounting the electronic component, a lid is fixed on the seal ring to close the upper end of the electronic component receiving space, thereby reducing the electronic component receiving space. Seal hermetically. The seal ring and the lid are fixed to each other by welding, particularly seam welding (sealing welding), in order to improve airtightness. Heat at the time of welding is also transmitted to the seal ring, and thermal stress is generated at and after welding at the joint between the seal ring and the ceramic wiring board. In order to prevent the ceramic wiring board from being damaged by this thermal stress, the sealing ring is usually fixed onto the ceramic wiring board using a soft solder.

  FIG. 10 is a schematic view showing an example of seam welding applied when the seal ring and the lid of the electronic component housing package are fixed. In the figure, the seal ring 155 and the lid 158 of the electronic component housing package 160 are seam welded by a seam welding machine 190. In the electronic component housing package 160, a seal ring 155 is fixed (brazed) by a soft braze 152 to a ceramic wiring substrate 150 on which a predetermined wiring pattern 143 and a metallization layer 145 for sealing are formed. The seal ring 155 is disposed on the metallized layer 145, and an electronic component 175 is mounted in the electronic component housing space RS defined by the seal ring 155 and the ceramic wiring substrate 150 by wire bonding. Bonding pads 172 formed on the electronic component 175 and bonding pads constituting the wiring pattern 143 in the ceramic wiring substrate 150 are connected by bonding wires 177.

  The seam welding machine 190 includes two roller electrodes 181a and 181b that are rotatably supported and arranged opposite to each other, a signal line 183a connected to the roller electrode 181a, and a signal line 183b connected to the roller electrode 181b. And a current controller 185 that is connected to the signal lines 183a and 183b and controls the intensity of the alternating current supplied to the roller electrodes 181a and 181b.

  The roller body 158 is pressurized by bringing the roller electrodes 181a and 181b into contact with the ridge on the upper surface side of the cover body 158, and in this state, an alternating current having a predetermined strength is supplied from the current controller 185 to the roller electrodes 181a and 181b. Then, the lid body 158 generates heat due to the contact resistance between the roller electrodes 181 a and 181 b and the lid body 158, softens, and is fused to the seal ring 155. Since these roller electrodes 181a and 181b move in the depth direction in the figure while rotating, the region softened by the above-described contact resistance and fused to the seal ring 155 is then solidified while maintaining a close contact state. That is, the lid body 158 is seam welded to the seal ring 155. The welding temperature is controlled by adjusting the strength of the alternating current supplied to each roller electrode 181a, 181b by a current controller 185. As described in Patent Document 4, the welding temperature can be controlled using a cooler (not shown).

  As described above, since the seam welding is to weld the lid 158 to the seal ring 155 using the contact resistance between the roller electrodes 181a and 181b and the lid 158, the heat generated during the seam welding is the lid 158. To the soft solder 152 through the seal ring 155. And since the temperature at the time of welding reaches about 1000 ° C., the phenomenon that the soft solder 152 remelts (reflows) during seam welding and crawls up the outer surface and the inner surface of the seal ring 155 inevitably occurs. .

  FIG. 11 is a schematic view showing how the soft solder reflowed during seam welding crawls up the outer surface and the inner surface of the seal ring. As shown in the figure, the soft solder 152 reflowed at the time of seam welding scoops up the outer surface and inner surface of the seal ring 155 and eventually reaches the upper surface of the seal ring 155, that is, the welded portion. When the soft solder 152 enters the welded portion, the joint between the seal ring 155 and the lid body 158 becomes brittle and sufficient airtightness cannot be achieved, or the contact resistance between the roller electrodes 181a and 181b and the lid body 158 abruptly increases. It becomes large and sparks occur, causing problems such as cracking of the lid 158. In addition, when the reflowed soft solder 152 adheres to the roller electrodes 181a and 181b, the current value flowing from the roller electrodes 181a and 181b to the lid 158 changes, resulting in non-uniform seam welding. Since all the constituent elements shown in FIG. 11 have already been described with reference to FIG. 10, the same reference numerals as those used in FIG. 10 are given to these constituent elements.

  In order to prevent the occurrence of such problems, for example, in the package for a semiconductor device of the invention described in Patent Document 1, a groove is provided on the side surface of the seal ring, and this groove prevents the soft solder from creeping up during seam welding. is doing. Further, in the electronic component housing package according to the invention described in Patent Document 3, the side surface of the seal ring having a predetermined plating layer formed on the surface is irradiated with laser light, and the upper side surface and the lower side surface of the seal ring are A metal coating layer different from the plating layers provided on the upper side surface and the lower side surface is provided in a streak shape between them, and this metal coating layer prevents creeping of the soft solder during seam welding.

  Further, the phenomenon that the soft solder crawls up the side surface of the seal ring occurs not only during the seam welding described above, but also when the seal ring is fixed on the wiring board. In a seal ring with a material, a brazing material is attached to a height of 1/6 to 2/3 of the side surface in advance, so that the brazing material at the time of fixing the seal ring on the wiring board (insulating base) Prevents crawls.

Japanese Patent Laid-Open No. 7-30007 JP 2003-133449 A JP 2005-268334 A JP 2003-245780 A

  In recent years, the electronic component housing package has been downsized along with the improvement in the mounting density of electronic components in electronic equipment, and the height of the seal ring has also been lowered accordingly. It is also easy for the wax to climb up the side of the seal ring and reach the upper surface of the seal ring.

  For example, when the size of the package for a semiconductor device described in Patent Document 1 is reduced, the width of the groove formed on the side surface of the seal ring must be narrowed. And the reflowed soft solder tends to reach the upper surface of the seal ring. Further, in the seal ring with a brazing material described in Patent Document 2, it seems that it is possible to prevent creeping of the brazing when the seal ring is fixed on the ceramic wiring board even if the height thereof is lowered. However, it is difficult to prevent the solder from creeping up during seam welding.

  In the electronic component housing package specifically described in Patent Document 3, the metal coating layer described above is formed on each of the outer surface and the inner surface of the seal ring. Difficult to irradiate light streak. When the above metal coating layer is formed by irradiating only the outer surface of the seal ring with a streak and the electronic component housing package is downsized, the seal ring is fixed on the ceramic wiring board and on the seal ring. The brazing of the soft brazing material twice over the seam welding of the lid to the top surface of the soft brazing material crosses the metal coating layer or scoops up the inner surface of the sealing ring and reaches the upper surface of the sealing ring. It becomes easy.

  The present invention has been made in view of the above, and an electronic component housing package that can easily accommodate an electronic component under high airtightness even when downsized, and an electronic component can be accommodated under high airtightness. It is an object of the present invention to obtain a manufacturing method of a seal ring that can easily produce a small electronic component housing package.

  An electronic component housing package of the present invention that achieves the above object includes a wiring board, a seal ring that is fixed to the wiring board by soft soldering, and a lid that is fixed to the sealing ring. And an electronic component housing package in which the lid is welded to the seal ring after the electronic component is mounted on the wiring board within the electronic component housing space defined by the seal ring, and the seal ring is formed into a frame shape A ring body made of a conductive material, a first coating formed on the ring body and forming at least an upper surface and an upper outer surface of the seal ring, and at least a lower surface of the seal ring formed on the ring body. A lower coating on the outer surface and a lower coating on the inner surface, and the wettability of the soft solder in the second coating is higher than the wettability of the soft solder in the first coating. It is an.

  In the electronic component housing package according to the present invention, since the first coating and the second coating are formed on the seal ring constituting the electronic component housing package, the wiring board can be used even when the electronic component housing package is downsized. The first coating can prevent the soft wax from creeping up when the seal ring is fixed to the seal ring and when the seal ring and the lid are welded. In addition, the seal ring can secure a good brazing property between the second coating and the soft solder, and can be fixed to the wiring board with high airtightness. As a result, in the electronic component housing package, it becomes easy to accommodate the electronic component with high airtightness even when the electronic component housing package is downsized.

  Hereinafter, embodiments of the electronic component housing package of the present invention and the manufacturing method of the seal ring used in the electronic component housing package will be described in detail with reference to the drawings. The present invention is not limited to the embodiments described below.

Embodiment 1 FIG.
FIG. 1 is a perspective view schematically showing an example of an electronic component housing package of the present invention, and FIG. 2 is a schematic view of a cross section taken along line II-II shown in FIG. The electronic component housing package 30 shown in these drawings is welded to the wiring board 10 on which the predetermined wiring pattern 1 is formed, the seal ring 20 fixed on the wiring board 10 with the soft solder 12, and the seal ring 20. And a lid 25.

  As the wiring board 10, for example, a ceramic wiring board having a single layer structure, a multilayer ceramic wiring board, or the like is used. Multilayer ceramic wiring boards can be broadly divided into low temperature co-fired ceramic (LTCC) wiring boards and high temperature co-fired ceramic (HTCC) wiring boards. Among these multilayer ceramic wiring boards, LTCC wiring boards are easier to obtain than those of HTCC wiring boards, and are excellent in high frequency characteristics, and are gold (Au), silver (Ag), silver (Ag) / palladium (Pd). Because it is possible to form a fine internal wiring (internal transmission line) pattern with high precision using a conductive paste such as silver, silver (Ag) / platinum (Pt), etc., it is a package for electronic components that support high frequency bands. This is suitable for obtaining a small electronic component housing package suitable for packaging.

  The wiring board 10 shown in FIG. 1 is a multilayer ceramic wiring board (hereinafter referred to as “multilayer ceramic wiring board 10”). In FIG. 1, only a part of the wiring pattern 1, that is, a plurality of pads 1a for wire bonding are used. A plurality of pads 1b connected to an external circuit (not shown) appear. In FIG. 1, the internal wiring (internal transmission line) pattern does not appear. A sealing metallized layer 5 is provided in a region where the seal ring 20 is to be fixed in the multilayer ceramic wiring substrate 10.

  The metallized layer 5 is for improving the brazing property between the multilayer ceramic wiring substrate 10 and the seal ring 20 and improving the airtightness. For example, gold (Au), tungsten (W), molybdenum (Mo), copper ( It is formed of a metal such as Cu) or silver (Ag). The film thickness of the metallized layer 5 is, for example, about 1-2 μm, and the line width is, for example, about 1-2 mm. The seal ring 20 is brazed onto the metallized layer 5 with a soft braze 12.

  The soft solder 12 fixes the seal ring 20 to the multilayer ceramic wiring board 10 with high airtightness, and at the time of welding the seal ring 20 and the lid body 25 and after welding, the seal ring 20 and the multilayer ceramic wiring board 10. The multilayer ceramic wiring board 10 is prevented from being damaged by the thermal stress generated at the joint. This soft solder 12 is a solder having a melting point as low as 450 ° C. or lower, but tin-lead eutectic solder (melting point is about 183 ° C.), tin-silver-copper lead-free solder (melting point is about 219 ° C.), etc. It is preferable to use one having a low melting point.

  When the seal ring 20 is fixed to the multilayer ceramic wiring substrate 10 with the soft solder 12, the soft solder 12 has high wettability at the lower outer surface and inner lower surface of the seal ring 20 as will be described later. Forms a fillet surface from the lower part of the seal ring 20 to the upper surface of the metallized layer 5. The thickness of the soft solder 12 between the metallized layer 5 and the seal ring 20 is, for example, about 10 to 20 μm.

  The seal ring 20 includes a ring main body 15 (see FIG. 2) made of an inorganic conductive material formed in a frame shape, and a first ring ring formed on the ring main body 15 and forming at least the upper surface and the upper outer surface of the seal ring 20. One coating 16 and a second coating 17 formed on the ring body 15 and forming at least the lower surface, the outer surface lower portion, and the inner surface lower portion of the seal ring 20 are provided. In the illustrated example, the ring body 15 has a rectangular frame shape, and the second coating 17 also forms the upper part of the inner surface of the seal ring 20.

  Examples of the inorganic conductive material that is the material of the ring body 15 include iron, nickel, and cobalt alloys (for example, “Kovar” (trade name) manufactured by Westing House), stainless steel, and the like. The first coating film 16 and the second coating film 17 are the largest characteristic portions in the electronic component housing package 30, and will be described in detail later with reference to FIG.

  When the seal ring 20 is fixed to the multilayer ceramic wiring board 10 with the soft brazing material 12, the multilayer ceramic wiring board 10 and the seal ring 20 define an electronic component housing space RS whose upper end is released. 1 and 2, the electronic component 35 is mounted on the multilayer ceramic wiring board 10 in the electronic component housing space RS. In the illustrated example, each of the pads 32 formed on the electronic component 35 is connected to a predetermined pad 1 a by a bonding wire 38, so that the electronic component 35 is mounted on the multilayer ceramic wiring substrate 10.

  The size required for the electronic component housing space RS varies depending on the size of the electronic component 35 to be mounted. Therefore, the size of the seal ring 20 is appropriately selected according to the size of the electronic component 35 to be mounted. When the electronic component 35 is small, the height and width of the seal ring 20 (line width of each side when seen in a plan view) are about several mm, for example. When the LTCC wiring board is used as the multilayer ceramic wiring board 10, if the height of the seal ring 20 exceeds 2 mm, the seal ring 20 and the LTCC wiring board are not bonded when the lid body 25 is welded to the seal ring 20 or after welding. Since cracks are likely to occur in the LTCC wiring board around the joint, the height of the seal ring 20 is preferably 2 mm or less.

  The lid body 25 is welded to the seal ring 20 for the first time after the electronic component 35 is mounted. The lid body 25 is an inorganic conductive material that can be easily welded to the seal ring 20, such as a seal ring. The substrate 25a is formed of the same inorganic conductive material as that used for the 20 ring bodies 15. In order to improve the weldability with the seal ring 20, it is preferable to form a gold film 25b having a film thickness of about 2 μm or more in a region welded to the seal ring 20 in the substrate 25a as shown in the figure. . The gold film 25b is formed, for example, by plating, and the upper limit value of the film thickness is appropriately selected in consideration of economy and productivity.

  Further, when seam welding the lid body 25 to the seal ring 20, the thickness of the substrate 25 a in the region welded to the seal ring 20 is set so that current easily flows from the lid body 25 to the seal ring 20. It is preferable to make it thinner than the thickness in other regions. By welding the lid 25 to the seal ring 20, the upper end of the electronic component housing space RS described above is closed, and the electronic component 35 is hermetically sealed in the electronic component housing package 30.

  The greatest feature of the electronic component housing package 30 having the above-described structure is that the first coating 16 and the second coating 17 are formed on the seal ring 20 under a predetermined arrangement. The structure of the seal ring 20 will be described in detail with reference to FIG.

  FIG. 3 is an enlarged schematic view showing a region defined by the ellipse III shown in FIG. As shown in the figure, the first coating 16 in the seal ring 20 is formed on the entire surface of the ring body 15 and forms the upper surface and the upper outer surface of the seal ring 20. Further, the second coating 17 is formed on the lower surface, the outer surface lower portion, and the inner surface of the ring body 15 after the first coating 16 is formed. Therefore, the second coating 17 forms the lower surface, the outer surface lower portion, and the inner surface of the seal ring 20.

  The materials of the first film 16 and the second film 17 are selected so that the wettability of the soft solder 12 in the second film 17 is higher than the wettability of the soft solder 12 in the first film 16. At this time, as for the material of the second coating 17, it is necessary to fix the seal ring 20 to the multilayer ceramic wiring substrate 10 with the soft braze 12 in an airtight manner, so that a good brazing property with the soft braze 12 can be obtained. Is selected as follows.

  Specific examples of the first coating 16 include a nickel (Ni) film or the like (hereinafter referred to as “nickel-containing coating”), and specific examples of the second coating 17 include a gold (Au) film or the like (hereinafter referred to as “the nickel-containing coating”). "Gold-containing coating"). These coatings 16 and 17 are formed by, for example, a plating method. It is also possible to form the second film 17 by solder plating using a soft solder. When a nickel-containing film is used as the first film 16, the film thickness can be, for example, about 2 to 6 μm. In addition, when a gold film is used as the second coating 17, the brazing strength rapidly decreases if the amount of diffusion of gold into the soft solder 12 is excessively increased (for example, about 4% or more by mass ratio). The thickness of the gold film is preferably about 0.01 to 0.05 μm from the viewpoint of suppressing a decrease in brazing strength.

  When the first coating 16 and the second coating 17 are arranged on the seal ring 20 as described above, the seal ring 20 is formed as a result of ensuring good brazing between the second coating 17 and the soft braze 12. It can be fixed to the multilayer ceramic wiring board 10 under high airtightness. Further, since the scooping up of the soft solder 12 is blocked by the first coating 16, even when the electronic component housing package 30 (see FIG. 1 and FIG. 2) is downsized, the seal ring 20 to the multilayer ceramic wiring board 10 can be removed. It is possible to easily prevent the soft solder 12 from climbing up to the upper surface of the seal ring 20 and entering the welded portion at the time of fixing or welding the seal ring 20 and the lid body 25. As a result, it is easy to weld the lid body 25 and the seal ring 20 under high airtightness without damaging the lid body 25.

  FIG. 4 is a conceptual diagram showing how the soft wax creeps up by the first coating. As shown in the figure, the soft solder 12 melted or reflowed when the seal ring 20 is fixed to the multilayer ceramic wiring board 10 or when the seal ring 20 and the lid body 25 are welded constitutes the seal ring 20. The surface of the second coating 17 is scooped up and eventually reaches the boundary between the second coating 17 and the first coating 16. However, since the wettability of the soft solder 12 in the first coating 16 is lower than the wettability in the second coating 17, the soft solder 12 does not enter the first coating 16 and does not enter the second coating 17. It stays and moves downward due to gravity. That is, the scooping up of the soft solder 12 is blocked by the first coating 16. In addition, the white arrow in FIG. 4 has shown notionally the moving direction of the melted soft wax 12. In the figure, for convenience, smudging is applied to the region where the soft solder 12 is distributed.

  Thus, in the seal ring 20 constituting the electronic component package 30, the scooping up of the soft solder 12 is blocked by the first coating 16. It is easy to adhere to the multilayer ceramic wiring board 10 under high airtightness, and it is also easy to weld the lid 25 and the seal ring 20 under high airtightness without damaging the lid 25. It is. Therefore, if this electronic component accommodation package 30 is used, a desired electronic component can be accommodated under high airtightness, and a highly reliable electronic component module can be easily obtained.

  The electronic component housing package 30 having such a technical effect is particularly a high-frequency electron equipped with a high-frequency integrated circuit such as a microwave integrated circuit (MIC) or a monolithic microwave integrated circuit (MMIC). It is suitable as an electronic component housing package for housing components in an airtight manner to obtain a high frequency module.

  FIG. 5 is a partially cutaway perspective view schematically showing an example of a high-frequency module configured using the electronic component housing package of the present invention. The high-frequency module 50 shown in the figure is one in which the high-frequency electronic component 45 is hermetically accommodated in the above-described electronic component accommodation package 30 (see FIGS. 1 and 2). The high frequency electronic component 45 is mounted in an electronic component housing space RS defined by the seal ring 20 and the multilayer ceramic wiring substrate 10 and mounted on the multilayer ceramic wiring substrate 10 by wire bonding. The bonding pads 42 formed on the high frequency electronic component 45 and the bonding pads 1 a constituting the wiring pattern 1 in the multilayer ceramic wiring substrate 10 are connected by bonding wires 48. 5 that are the same as those shown in FIG. 1 are assigned the same reference numerals as those used in FIG. 1 and description thereof is omitted.

  The high frequency module 50 is connected to an external circuit (not shown) via each of the pads 1b constituting the wiring pattern 1, and a control signal or a high frequency is transmitted between the external circuit and the high frequency electronic component 45. By inputting / outputting a signal (RF signal) or the like, a predetermined function of the high-frequency electronic component 45, for example, a function such as signal amplification or attenuation, or oscillation, is achieved. Since the high-frequency electronic component 45 is easily housed in the electronic component housing package 30 in an airtight manner, the high-frequency module 50 can easily obtain a high reliability over a long period of time. Such a high frequency module 50 can be manufactured by a conventional method except that the electronic component housing package of the present invention is used.

  FIG. 6 is a process diagram showing an example of a method for manufacturing the high-frequency module 50 described above. In the example shown in the drawing, a multilayer ceramic wiring board is manufactured by two processes of steps S61 and S62, a seal ring is manufactured by three processes of steps S71 to S73, and then an electronic component housing package is assembled in process S81. A high-frequency module is obtained in two steps 91 and 92. Hereinafter, each step will be described with reference to the reference numerals used in FIG. 5 as appropriate.

  In the above step S61, a wiring pattern is formed on each of a predetermined number of green sheets by a printing method, these green sheets are punched to form cavities, through holes, and the like, stacked, and compression molded. Sintering to obtain a multilayer ceramic substrate. In step S62, the multilayer ceramic substrate is subjected to surface treatment such as plating or metalizing (formation of the metallized layer 5) to obtain the multilayer ceramic wiring substrate 10.

  In step S71, the ring body 15 (see FIG. 2) is produced by machining or pressing, and in step S72, the first coating 16 and the second coating 17 are formed on the ring body 15 by plating. In step S73, when a relatively thick gold-containing film is formed as the second film 17 in step S72, a preliminary soldering process is performed to reduce the film thickness of the gold-containing film to about 0.05 μm or less. When a film other than the gold-containing film is formed as the second film 17 in step S72, or when a gold-containing film having a film thickness of about 0.05 μm or less is formed, the process 73 can be omitted. . The seal ring 20 is obtained by performing the process 71 and the process 72, or performing the processes 71-73.

  In step S <b> 81, the seal ring 20 is fixed (brazed) to the multilayer ceramic wiring substrate 10 with the soft solder 12, and the electronic component housing space RS is defined by the multilayer ceramic wiring substrate 10 and the seal ring 20. For example, a paste-like soft solder is applied onto the metallized layer 5 in the multilayer ceramic wiring substrate 10, the seal ring 2 is placed thereon, heated in a furnace to melt the soft solder, and then cooled to seal The ring 20 is fixed (brazed) to the multilayer ceramic wiring board 10. Separately from this, the lid body 25 of the electronic component housing package 30 is produced.

  In step S91, the high frequency electronic component 45 is mounted on the multilayer ceramic wiring board 10 in the electronic component housing space RS. Thereafter, the lid 25 is seam welded to the seal ring 20 in step S92, whereby the high frequency module 50 is obtained.

Embodiment 2. FIG.
The seal ring used in the electronic component housing package of the present invention can be easily obtained by, for example, the seal ring manufacturing method of the present invention including the following first plating process and second plating process. Hereinafter, the case where the seal ring 20 shown in FIG. 3 is manufactured will be described as an example, and the reference numerals used in FIG.

(First plating process)
In the first plating step, a first film covering the entire surface of the ring body is formed on the ring body made of a conductive material formed in a frame shape by plating. A part of the first film formed in the first plating step becomes the first film 16 (see FIG. 3) in the seal ring 20 as it is. The formation of the first film 16 can be performed by, for example, electrolytic plating using a desired plating bath or electroless plating.

(Second plating process)
In the second plating step, the upper surface and the outer surface upper portion of the first film formed in the first plating step are covered with a masking material, and the lower surface, the outer surface lower portion, and the inner surface lower portion are exposed, and the first film is plated. To form a second coating on the exposed surface of the first coating, the wettability of which is higher than that of the first coating. The upper part of the inner side surface of the first coating may be exposed without being covered with a masking material, or may be covered with a masking material. The second film formed in the second plating step becomes the second film 17 (see FIG. 3) in the seal ring 20 as it is. That is, the seal ring 20 is obtained by performing up to the second plating step.

  As the above-mentioned masking material, for example, an adhesive tape can be used. However, since the seal ring has a small size, it is difficult to increase the working efficiency by masking using the adhesive tape, and as a result, it is difficult to suppress the manufacturing cost. From the viewpoint of manufacturing a seal ring at a low cost, it is preferable to use a masking material having a recess having a predetermined shape.

  FIG. 7 is a perspective view schematically showing an example of a masking material used in the second plating step. The masking material 100 shown in the figure is in a ring body 15 (see FIG. 3; hereinafter referred to as “first seal ring 20A”) in which a first film 16 (see FIG. 3) is formed on the entire surface in the first plating step. It has a plate shape with a recess 100a having a shape and size to which one end in the height direction fits. The shape of the bottom surface BS of the recess 100a is the same as the contour shape defined by the outer edge of the first seal ring 20A when the first seal ring 20A is viewed in plan. Therefore, by fitting one end of the first seal ring 20A in the height direction into the recess 100a, the upper surface and the outer surface upper portion of the first coating 16 are covered by the masking material 100, and the lower surface, the outer surface lower portion, and the entire inner surface are covered. Can be exposed. The depth of the recess 100a is shallower than the height of the first seal ring 20A.

  In order to prevent the second coating 17 (see FIG. 3) from being formed at an undesired location in the first seal ring 20A, the inner dimension of the recess 100a is the outer dimension when the first seal ring 20A is viewed in plan. It is preferable to make it the same as the size or slightly smaller than the outer size when the first seal ring 20A is viewed in plan. By selecting the inner dimension of the recess 100a in this way, the bottom surface and the inner wall of the recess 100a can be brought into close contact with the first seal ring 20A, so that the second coating is applied to an undesired portion of the first seal ring 20A. It becomes possible to prevent 17 from being formed. The depth of the concave portion 100a depends on how much the width of the first coating 16 (see FIG. 3) in the upper portion of the outer surface of the target seal ring 20 (the width in the height direction of the seal ring 20) is set. Are selected as appropriate. The masking material 100 is preferably made of a material having high corrosion resistance and causing elastic deformation, such as a fluorine-based resin such as polytetrafluoroethylene.

  The second coating 17 (see FIG. 3) is an exposed surface of the first seal ring 20A by performing electroplating or electroless plating in a state in which one end in the height direction of the first seal ring 20A is fitted in the recess 100a. Formed on top. By forming up to the second coating 17 in this manner, the first coating 16 forms the upper surface and the upper outer surface, and the second coating 17 forms the second seal ring that forms the lower surface, the lower outer surface, and the entire inner surface. The target seal ring 20 is obtained. When a gold plating film is formed as the second coating film 17, as already described in the first embodiment, the film thickness of the gold plating film is preferably in the range of 0.01 to 0.05 μm.

  When the second coating is formed as described above, the masking operation is completed by a simple operation of fitting one end portion in the height direction of the first seal ring 20A into the concave portion 100a of the masking material 100. 20 can be easily obtained while suppressing the manufacturing cost. If this seal ring 20 is used, as already described in the first embodiment, it becomes easy to produce an electronic component housing package that can easily house an electronic component under high airtightness even when downsized.

  The electronic component housing package of the present invention and the manufacturing method of the seal ring constituting the electronic component housing package have been described above with reference to the embodiments. However, as described above, the present invention is limited to the above embodiments. Is not to be done.

  For example, the wiring board constituting the electronic component housing package may be a ceramic wiring board having a single-layer structure in addition to the multilayer ceramic wiring board, or may be another wiring board. The form of the wiring pattern on the wiring board can be selected as appropriate. For example, a ball grid array may be disposed on the lower surface so that it can be used as an interposer substrate.

  The shape of the ring body constituting the seal ring is not limited to the rectangular frame shape, and may be another frame shape such as an annular frame shape. Moreover, the 1st film should just be formed in the upper surface and outer surface upper part of a ring main body at least, and does not need to be formed in the whole surface of a ring main body. If necessary, an undercoat layer can be interposed between the first coating and the ring body. The second coating does not have to form the entire lower surface, outer surface lower surface, and inner surface of the seal ring, and may form the lower surface, outer surface lower surface, and inner surface lower surface of the seal ring. Good. In this case, the first film may form the upper part of the inner surface of the seal ring, or another film may form the upper part of the inner surface.

  FIG. 8 is a cross-sectional view schematically showing an example of a seal ring in which the second coating forms a lower surface, a lower outer surface, and a lower inner surface. In the seal ring 120 shown in the figure, the first coating 16 forms the upper surface, the outer surface upper portion, and the inner surface upper portion, and the second coating 117 forms the lower surface, the outer surface lower portion, and the inner surface lower portion. In addition, about the structural members other than the 2nd film | membrane 117 among the structural members shown in FIG. 8, the same referential mark as the referential mark used in FIG. 3 is attached | subjected, and the description is abbreviate | omitted. Such a seal ring 120 can be manufactured as follows, for example.

  FIG. 9 is a perspective view schematically showing an example of a masking material used when manufacturing the seal ring 120 described above. The masking material 130 shown in the figure is provided with a recess 130a instead of the recess 100a in the masking material 100 shown in FIG. 7, and the shape of the bottom surface BS in the recess 130a is the first seal ring 20A (FIG. 7). The shape is the same as when viewed in plan. Accordingly, by fitting one end of the first seal ring 20A in the height direction into the recess 130a, the masking material 130 covers the upper surface, the outer surface upper portion, and the inner surface upper portion of the first coating 16 (see FIG. 3), and the lower surface. The lower portion of the outer surface and the lower portion of the inner surface can be exposed. The seal ring 120 described above can be manufactured in the same manner as the seal ring 20 described above, except that the one end in the height direction of the first seal ring 20A is covered with the masking material 130 in this way.

  The positions of the boundary between the lower part of the outer surface and the upper part of the outer surface and the boundary between the lower part of the inner surface and the upper part of the inner surface must be at a position corresponding to 1/2 of the height of the seal ring. Rather, considering the brazing property between the seal ring and the wiring board, and the barrier property against the rising of the soft brazing by the first coating, the kind of the soft brazing used for fixing the seal ring, the first coating and the second coating It can be appropriately selected according to the material of each coating, the height of the seal ring, or the like. In addition to the above, the electronic component housing package of the present invention and the manufacturing method of the seal ring used for the electronic component housing package can be variously modified, modified, combined, and the like.

It is a perspective view which shows roughly an example of the electronic component accommodation package of this invention. It is the schematic of the II-II line cross section shown in FIG. It is the schematic which expands and shows the area | region demarcated by the ellipse III shown in FIG. It is a conceptual diagram which shows a mode that the rising of a soft solder | pewter is interrupted | blocked by the 1st film in the electronic component accommodation package shown in FIG. It is a partial notch perspective view which shows roughly an example of the high frequency module comprised using the electronic component accommodation package of this invention. It is process drawing which shows an example of the manufacturing method of the high frequency module shown in FIG. It is a perspective view which shows roughly an example of the masking material used at the 2nd plating process in the manufacturing method of the seal ring of this invention. It is sectional drawing which shows roughly an example of the seal ring which a 2nd film | membrane comprises a lower surface, an outer surface lower part, and an inner surface lower part among the seal rings which comprise the electronic component accommodation package of this invention. It is a perspective view which shows roughly an example of the masking material used when manufacturing the seal ring shown in FIG. It is the schematic which shows an example of the seam welding applied when adhering the seal ring and cover body of an electronic component accommodation package. It is the schematic which shows a mode that the soft solder | pewter reflowed at the time of the seam welding shown in FIG. 11 scoops up the outer surface and inner surface of a seal ring.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Wiring board 12 Soft solder | pewter 15 Ring main body 16 1st film | membrane 17,117 2nd film | membrane 20,120 Seal ring (2nd seal ring)
20A First seal ring 25 Lid 100, 130 Masking material 100a, 130a Recess RS Electronic component accommodation space BS Bottom of recess

Claims (12)

An electronic component housing space defined by the wiring board and the seal ring, comprising: a wiring board; a seal ring fixed on the wiring board with a soft solder; and a lid fixed on the seal ring. An electronic component housing package in which the lid is welded to the seal ring after mounting the electronic component on the wiring board,
The seal ring includes a ring body made of a conductive material formed in a frame shape, a first coating formed on the ring body and forming at least an upper surface and an outer surface of the seal ring, and the ring body A second coating formed on the seal ring and forming at least a lower surface, a lower portion of the outer surface, and a lower portion of the inner surface;
The electronic component housing package, wherein the wettability of the soft solder in the second coating is higher than the wettability of the soft solder in the first coating.   The first coating is formed on the entire surface of the ring body, and the second coating is formed on the first coating to form at least a lower surface, an outer surface lower portion, and an inner surface lower portion of the seal ring. The electronic component housing package according to claim 1.   The electronic component housing package according to claim 1, wherein the second coating forms a lower surface, an outer surface lower portion, and an inner surface of the seal ring.   The electronic component housing package according to any one of claims 1 to 3, wherein the first coating is a nickel-containing coating and the second coating is a gold-containing coating.   5. The electronic component housing package according to claim 1, wherein the second coating is a gold plating film having a thickness in a range of 0.01 to 0.05 μm.   The said cover body has the board | substrate which consists of an electroconductive material, and the gold film | membrane with a film thickness of 2 micrometers or more formed in the area | region welded to the said seal ring among this board | substrate. The electronic component accommodation package as described in any one of 1-5. An electronic component housing space fixed on the wiring board by soft soldering and having its upper end released together with the wiring substrate is determined, and the electronic component housing space is mounted on the wiring substrate in the electronic component housing space. A manufacturing method of a seal ring in which a lid that closes the top is welded to the upper surface,
A first plating step of forming, by plating, a first film covering the entire surface of the ring body on the ring body made of a conductive material formed into a frame shape;
The upper surface of the first coating and the upper portion of the outer surface are covered with a masking material, and plating is performed with the lower surface, the lower portion of the outer surface and the lower portion of the inner surface exposed. A second plating step of forming a higher second coating on the exposed surface of the first coating;
The manufacturing method of the seal ring characterized by including. The masking material includes a recess having a shape and size into which one end in the height direction of the ring body on which the first film is formed fits,
The method of manufacturing a seal ring according to claim 7, wherein the plating in the second plating step is performed in a state where the one end portion is fitted in the concave portion of the masking material.   The shape of the bottom surface of the concave portion is the same as a contour shape defined by an outer edge of the ring body when the ring body on which the first coating is formed is viewed in plan view. A manufacturing method of a seal ring.   The method for manufacturing a seal ring according to claim 8, wherein the shape of the bottom surface of the concave portion is the same as the shape of the ring main body on which the first coating film is formed in plan view.   The method for producing a seal ring according to any one of claims 7 to 10, wherein a nickel-containing film is formed as the first film, and a gold-containing film is formed as the second film. The method for manufacturing a seal ring according to any one of claims 7 to 11, wherein a gold plating film having a thickness in a range of 0.01 to 0.05 µm is formed as the second coating.

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