JP2008028050A - Manufacturing method of lid for package - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a lid for a package capable of adjusting the thickness of a desired part of a wax material layer formed by printing it with a wax material paste. <P>SOLUTION: The wax material layer 5 having a predetermined width with a shape corresponding to the brazed surface of the package 1 is formed on one surface of the lid 2 by printing it with a paste-like wax material. When the package 1 and the lid 2 are welded by brazing, the wax material layer 5 is printed on the brazed surface of the package with the paste-like wax material so that the width of part thereof is different. The thickness of the wax material layer 5 is adjusted by changing the width of the wax material layer 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a package lid that houses various electronic components.

  The package is made into a small chip suitable for high-density mounting on the circuit board of the electronic device. As various devices are downsized, the package is further reduced in size and weight, and the demand for cost reduction is increasing. Yes.

  Such a conventional general package is configured as shown in FIG. The package 100 is configured by a ceramic substrate formed in a substantially dish shape, and a quartz resonator 102, for example, is mounted in an internal cavity 101. The opening end of the package 100 is formed in a rectangular ring shape, and a metallized layer 103 is provided in the rectangular ring shape at the opening end. A lid 104 is welded to the metallized layer 103 formed at the opening end of the package 100 by brazing.

  The lid body 104 is formed of flat Kovar (iron (Fe) / nickel (Ni) / cobalt (Co) alloy), and the metallized layer 103 is formed on the outer periphery of the lid body 104 as shown in FIG. A rectangular annular brazing material layer 105 made of a brazing material is formed in the same shape and area. After the lid 104 is bonded so that the metallized layer 103 and the brazing filler metal layer 105 coincide with each other, the lid 104 is placed in a sealing furnace and heated in a vacuum atmosphere or by reflow, for example, so that the lid 104 is opened. As a result, the cavity 101 of the package 100 is hermetically sealed.

  As a method of forming the brazing filler metal layer 105 formed on the lid 104, for example, a method of punching out a low-temperature metal brazing material made of an Au / Sn alloy in the form of a foil into a small rectangular ring and attaching it to the lid 104, A method of forming a clad lid by simultaneously rolling a metal plate and a metal brazing material as materials of the lid 104, as disclosed in Japanese Patent No. 3248842 (Patent Document 1), or As disclosed in Japanese Patent Application Laid-Open No. 2004-186428 (Patent Document 2), a method of printing a paste-like brazing material by screen printing is known.

  Next, a method for manufacturing the lid 104 disclosed in Patent Document 2 will be described. First, Ni plating is applied to both surfaces of a band-shaped lid member such as Kovar, and then Au plating is applied to a Ni base on one surface. A frame-shaped resist is printed on the Au plating, and then only the Au plating is removed except for the resist-coated portion. Next, the resist is removed to expose the Au plating. This Au plating is for improving the wettability to the brazing material. Next, a solder paste containing a binder (a paste-like brazing material made of a low-temperature metal brazing material having a melting point of about 280 degrees Celsius) is screen-printed on the Au plating, and then this is reflowed on the Au plating. A brazing filler metal is applied to form a brazing filler metal layer 105. Thereafter, the outer shape of the lid 104 is punched out by pressing.

Japanese Patent No. 3248842 JP 2004-186428 A

  In the method for manufacturing a lid for a package described in Patent Document 1 described above, since the metal brazing material is provided on the entire surface on the sealing side of the lid, there is a problem that the amount of the metal brazing material cannot be reduced. In addition, since the metal brazing material is provided on the entire surface of the lid on the sealing side, when the lid is sealed, the metal brazing material other than the metal brazing material on the sealing surface is also melted. There is a problem that a large amount of irradiation heat is required and the ceramic substrate is adversely affected. Furthermore, since a foil-like metal brazing material is used, there is a limit to reducing the thickness of the brazing material layer.

  On the other hand, in the lid manufacturing method described in Patent Document 2, when the brazing paste is screen-printed in a rectangular ring shape and then reflowed to form the brazing filler metal layer 105, the brazing paste is a fluid. As shown in FIG. 11, the central portion 105a is thin and the edge portion 105b is raised and thick, resulting in a film thickness difference TR. This is said to be a meniscus due to the surface tension phenomenon. The meniscus becomes more prominent when the brazing paste is dissolved by reflow. When the brazing filler metal layer 105 having such a film thickness difference TR is bonded to the metallized layer 103 and heated, a gap 106 is formed in the central portion where the film thickness is thin, and the cavity 101 of the package 100 is not hermetically sealed. Serious problems arise. In addition, void 107 is generated due to air entering the central portion, resulting in incomplete sealing. For example, when the package 100 is heated, the void expands and the opening end of the package 100 and the lid 104 are separated from each other. There was a problem to do. On the other hand, the edge portion having a large film thickness has a problem in that excess brazing material flows out of the package 100 and the outflow soul 105c protrudes.

  This invention solves these problems, and provides the manufacturing method of the cover body for packages which can adjust the film thickness of the brazing material layer formed by printing a brazing material paste in a desired site | part. Objective.

  In order to solve the above-mentioned problem, a manufacturing method of a lid for a package according to the present invention includes a brazing material layer having a predetermined width corresponding to a surface to be brazed of a package on one surface of the lid. When the package is formed by printing and the package and the lid are brazed through the bonding layer, the brazing material layer is a paste-like brazing so that a part of the brazing material layer is different in width from the brazed surface of the package. The gist is to print the material.

  A rectangular annular metallized layer having a predetermined width is formed around the package, and it is desirable that the brazing material layer has a partly different width to correspond to the uneven shape of the metallized layer.

  It is desirable that the width of the brazing material layer at the part where the film thickness is different is partially adjusted to be adjusted.

  According to the method for manufacturing a lid for a package according to claim 1 of the present invention, when the brazing filler metal is printed on the lid to form the brazing filler metal layer, the width of a part of the brazing filler metal layer is different. When printing is performed in this manner, the surface tension of the paste-like brazing material changes depending on the width, and the film thickness can be changed. The film thickness of the brazing material layer can be formed uniformly, and the lid can be welded to the brazed surface of the package with a uniform film thickness. As a result, the generation of voids and voids in the brazing material layer is suppressed, and the package cavity can be hermetically sealed.

  According to the invention of claim 2 of the present invention, a rectangular annular metallized layer having a predetermined width is formed around the package, and even if this metallized layer has an uneven shape, the width of a part of the brazing material layer It is possible to adjust the film thickness of the brazing material layer in accordance with the unevenness of the metallized layer. In other words, in ceramic packages, sink deformation or warpage deformation occurs due to shrinkage deformation or volume change during firing, and the brazed surface of the open end is partially deformed to form a metallized layer on the uneven surface. There is a case. Even with such uneven surfaces, the film thickness of the brazing material layer can be adjusted, so that the lid is welded to the brazed surface of the package due to the change in film thickness, and the package cavity is hermetically sealed. can do.

  According to the invention described in claim 3 of the present invention, it is possible to easily adjust the film thickness of the brazing filler metal layer by making the width of the brazing filler metal layer partially different corresponding to the portion where the film thickness is varied. It becomes. For this reason, the cavity of a package can be welded airtight easily.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. 1 and 4 show a package 1 and a lid 2 according to the present invention. As shown in FIG. 4, the package 1 is made of ceramic formed in a substantially dish shape, and a quartz resonator or the like is mounted in the internal cavity 1a. An open end of the package 1 is formed in a rectangular ring shape, and a metallized layer 3 is provided in a rectangular ring shape on the entire surface of the open end. A lid 2 is welded to the metallized layer 3 formed at the open end of the package 1 by brazing.

  The lid 2 is formed of flat Kovar (iron (Fe), nickel (Ni), cobalt (Co) alloy) and the metallized layer 3 is formed on the outer periphery of the lid 2 as shown in FIG. Similarly, a rectangular annular brazing material layer 5 made of a brazing material is formed. After the lid 2 is joined so that the metallized layer 3 and the brazing filler metal layer 5 coincide with each other, the lid 2 is put in, for example, a sealing furnace and heated in a vacuum atmosphere or by reflow to thereby form the metallized layer 3 at the opening end of the package 1. As a result, the cavity 1a of the package 1 is hermetically sealed.

  In the present invention, the width of a part of the brazing filler metal layer 5 of the lid 2 configured as described above is made different from the width of other parts. That is, as shown in FIG. 2, the rectangular annular brazing material layer 5 formed on the outer peripheral edge of the lid 2 is formed so that the width of the central part of the long side 5a gradually becomes wider from the short side 5b. Has been. As a result, the width W2 at the center is made larger than the width W1 near the short side. The short side 5b is formed to have a width W1. The width W2 at the center is smaller than the width of the metallized layer 3.

  When the width W2 of the central portion on the long side in the brazing material layer 5 is formed larger than the width W1 in the vicinity of the short side, when the brazing material layer 5 is formed by printing the paste-like brazing material, the normal width is short. Since the surface tension on the side is weakened, the paste-like brazing material on the short side becomes almost the same as the film thickness in the central portion, and is formed almost uniformly as shown in FIG.

  Thus, when the film thickness of the brazing filler metal layer 5 formed by printing the paste-like brazing filler metal is made uniform over the entire circumference, the lid is uniform with respect to the metallized layer 3 at the opening end of the package 1. Since it is welded with a thickness, generation of voids and voids in the brazing material layer 5 is suppressed, and the cavity 1a of the package 1 can be hermetically sealed.

  The lid 2 described above may be any material that has a linear expansion coefficient substantially equal to the linear expansion coefficient of the ceramic package 1 and can withstand the brazing temperature. In addition to the Kovar described above, an iron (Fe) alloy A material that can withstand the brazing temperature, such as ceramic or ceramic, can be used.

  Further, the brazing material layer 5 is made of a metal having a low melting temperature such as an Au / Sn alloy (melting point is about 280 degrees Celsius), but other materials for the brazing material layer 5 include high-temperature solder, A silver (Ag) brazing material, an aluminum (Al) brazing material, or the like may be used.

  Next, an outline of a method for manufacturing the lid 2 of the package 1 will be described. The lid 2 is manufactured from a band-like lid member 10 such as Kovar as shown in FIG. Subsequently, a guide hole 10a for conveyance positioning is formed in the lid member 10 by continuous pressing.

  Next, Ni plating and Au plating are applied to the lid member 10, and then a resist is printed and applied with reference to the guide hole 10 a, and then the Au plating is removed except for a portion where the resist is applied, and then the resist is removed. , Au plating is exposed. By applying Au plating in this way, the wettability to the brazing material is improved and the molding accuracy of the brazing material layer 5 is improved.

  Next, the solder paste containing the binder is screen-printed on the Au plating, and then reflowed to deposit the brazing material on the Au plating to form the brazing material layer 5 as shown in FIG. . In addition, the application of the brazing material paste may use, for example, a dispenser in addition to screen printing.

  Thereafter, the outer shape of the lid body 2 is punched out by pressing, and the lid body 2 shown in FIG. 1 is completed. In this way, the process up to the process of forming the brazing material layer can be handled as a unit of the lid member, so that productivity can be improved. Moreover, since the brazing filler metal layer 5 can be formed in a desired thickness, the amount of brazing filler metal used can be reduced.

  FIG. 6 shows a second embodiment for adjusting the film thickness of the brazing filler metal layer according to the present invention. In FIG. 6, the rectangular annular brazing material layer 21 formed on the outer peripheral edge of the lid 20 has a bulging portion 22 formed at the inner corner where the long side 21a and the short side 21b intersect. As a result, the area of the brazing filler metal layer 21 at the corner becomes larger than that of the conventional one, and the surface tension is weakened, so that the paste-like brazing filler is almost the same as the film thickness in the central portion and is formed almost uniformly. .

  FIG. 7 shows a third embodiment for adjusting the film thickness of the brazing filler metal layer formed on the lid according to the present invention. The package 1 formed in a substantially dish shape by ceramic causes sink deformation and warpage deformation due to shrinkage deformation and volume change during firing, and as shown in FIG. It may be formed in a concave shape. For this reason, the metallized layer 3 serving as a brazing surface provided on the entire surface of the opening end is also formed in a concave shape. When a flat lid is welded to such a concave metallized layer 3, voids and voids are generated in the welded brazing material layer 5, resulting in a problem that the cavity cannot be hermetically sealed.

  For this reason, as shown in FIG. 7, the width | variety of the rectangular annular brazing material layer 31 formed in the outer periphery of the cover body 30 so that the width | variety of the center part of the long side 31a becomes gradually narrow from the short side 31b. Is formed. As a result, the width W4 at the center is made smaller than the width W3 near the short side. The width of the brazing material layer 31 is appropriately set according to the depth of the concave surface formed at the opening end of the package 1. Note that the width of the short side 31b can be changed in the same manner as the long side 31a.

  As described above, by changing the width of the brazing filler metal layer 31, the surface tension at the central portion of the brazing filler metal layer 31 changes, and the film thickness at the central portion increases. Therefore, even if the lid 30 is welded to the concave metallized layer 3 formed at the opening end of the package 1, the concave portion is filled with the brazing material, so that generation of voids and voids is prevented, and the package 1 The cavity 1a can be hermetically sealed.

  Although the present invention has been specifically described above based on the embodiments, it is needless to say that the present invention is not limited to the above embodiments and can be variously modified without departing from the gist thereof. In the above-described embodiment, the flat lid is welded to the opening end of the package formed in a substantially dish shape by the ceramic, but conversely, the lid body is formed in a substantially dish shape and the solder is formed at the opening end. A material layer may be formed and welded to a package formed in a flat plate shape. In addition to the ceramic, the package may be changed to a material such as a metal that has substantially the same linear expansion coefficient as the lid and can withstand the brazing temperature. Further, an electronic component other than the crystal unit may be accommodated in the cavity formed by the package and the lid, and the package and the lid may be appropriately deformed according to the shape of the electronic component to be accommodated. .

  The method for manufacturing a lid for a package according to the present invention can be used for a lid that hermetically seals an electronic component such as a crystal resonator housed in a package.

It is a perspective view which shows the cover body for packages by this invention. It is a top view of the cover body shown in FIG. It is a perspective view which shows the package and cover body by this invention. It is a principal part expanded sectional view which shows the brazing filler metal layer of the cover body by this invention. It is explanatory drawing which shows the printing process of the cover body by this invention. It is a top view which shows the 2nd Example of the cover body for packages by this invention. It is a top view which shows the 3rd Example of the cover body for packages by this invention. It is explanatory drawing which shows the relationship between the cover body and package by 3rd Example shown in FIG. It is a top view which shows the cover body for the conventional package. It is sectional drawing which shows a state by welding a cover body to the conventional package. It is a principal part expanded sectional view which shows the brazing filler metal layer of the conventional lid.

Explanation of symbols

1 Package 1a Cavity 2 Lid 3 Metallized layer 5 Brazing material layer

Claims (3)

A brazing material layer having a predetermined width corresponding to the brazed surface of the package is formed on one surface of the lid by printing a paste-like brazing material, and the package and the lid are connected via the bonding layer. A manufacturing method for brazing,
A method for manufacturing a lid for a package, comprising: printing a paste-like brazing material by varying a width of a part of the brazing material layer with respect to a brazed surface of the package.   The rectangular annular metallization layer having a predetermined width is formed around the package, and the brazing material layer has a partly different width to correspond to the uneven shape of the metallization layer. Manufacturing method for a package lid. The method for manufacturing a lid for a package according to claim 1, wherein the brazing material layer has a partly different width to adjust the film thickness.

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