JP2009004562A - Ceramic package and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ceramic package that can clearly distinguish an edge inside a surface conductor layer from a conductive layer, and to provide a method of manufacturing the same. <P>SOLUTION: A first conductive layer 21 is formed on a cavity 5 side surface (upper surface) of a lower ceramic board 13 along one longer inner side of a frame 19, and the right end of this first conductive layer 21 extends to the upper right corner part of the ceramic package 1. The surface of the first conductive layer 21's central part is covered with an insulating layer 25 made of aluminum. In other words, when the ceramic package 1 is seen from the cavity 5's side (upper surface side), the insulating layer 25 is formed along the longer inner side of the frame 19 so that the first conductive layer 21 may not be exposed. This makes the insulating layer 25 look to be as if it were formed adjacent to the inner side of the frame 19 when seen from the upper surface side, and the first conductive layer 21 is seen between the frame 19 and the insulating layer 25. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a ceramic package for housing electronic components such as a crystal resonator package, a crystal oscillator package, and a SAW (Surface Acoustic Wave) filter package, and a method of manufacturing the same.

Conventionally, a ceramic package has been used as a package for accommodating a crystal unit or the like.
This ceramic package is a plate-shaped ceramic package provided with a cavity (concave portion) for accommodating a crystal resonator and an IC chip in the center, and the periphery thereof is surrounded by a wall-shaped peripheral portion (patented) References 1, 2, and 3).

  Inside the cavity, a pad for mounting a crystal oscillator, a lead (conductive layer) electrically connected to the pad, and the like are provided. In addition, a surface conductor layer (trace layer, seal ring) is formed on the surface of the peripheral portion by metallization or the like for tracing (or for joining the lid) used for positioning during image processing. .

  Among these, the conductive layer connected to the pad is usually formed along the outer periphery of the bottom of the cavity and extends so as to be taken out from the corner of the ceramic package. This is because wiring or the like for connecting to the IC chip is formed at the center of the bottom of the cavity.

For example, if the crystal pad trace in a crystal unit is wired in the center of the cavity, there is concern about interference with the crystal blank, so it may be possible to form the crystal pad trace in the sidewall around the cavity. However, it is difficult because the side wall is narrow. Therefore, also from this point, a conductive layer such as a quartz pad trace is formed along the outer periphery of the bottom surface of the cavity.
JP-A-6-104687 JP 11-251839 A JP 2003-8380 A

However, in the above-described prior art, since the surface of the conductive layer or the surface conductor layer is plated with gold or the like, there are cases where it is not preferable when the operation is automatically performed using image processing.
That is, the operation of mounting the crystal resonator and the IC chip on the ceramic package is automated by a machine. At that time, the upper surface of the ceramic package (the surface having the cavity opening) is photographed and an image thereof (for example, 2 The surface of the conductive layer or surface conductor layer is plated with gold or the like, and in recent years, it is close to the surface conductor layer when viewed from the top of the package. Alternatively, there is a tendency that the conductive layer tends to be disposed in an overlapping manner, so that it is difficult to distinguish between the conductive layer and the surface conductor layer during image processing.

  Specifically, when mounting a crystal unit or IC chip, for example, the line along the cavity-side edge of the surface conductor layer is positioned as the reference line, so the conductive layer and the surface conductor layer cannot be distinguished. However, there is a problem that, for example, the side edge of the conductive layer is erroneously determined as the reference line, and as a result, the mounting deviation of the crystal resonator or the like occurs.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a ceramic package that can clearly distinguish an inner edge of a surface conductor layer from a conductive layer, and a method of manufacturing the same.

  (1) The invention of claim 1 has a substrate body having a front surface and a back surface and a plurality of insulating layers laminated, and an opening on the surface of the substrate body, and a side surface and a bottom surface on which electronic components are mounted. A cavity, a surface conductor layer provided on the surface of the substrate body so as to surround the opening of the cavity, and provided with a peripheral plating layer on the surface; and provided along an outer peripheral portion of at least a part of the cavity; A ceramic package comprising: a conductive layer comprising an inner plating layer composed of the same main component as the surface conductor layer; and an image identification mark provided on at least a part of the surface of the conductive layer. And

  In the present invention, since an image identification mark is provided on the surface of the conductive layer along the outer periphery of the cavity, when processing an image taken of the ceramic package from the cavity side (for example, the upper side or the upper surface side) (For example, when creating a binarized image), the edge of the surface conductor layer on the cavity side can be clearly recognized. Therefore, since this edge can be used as a reference line for positioning when mounting an electronic component, positioning with high accuracy can be performed.

  Moreover, as each said plating layer, what plated nickel plating and gold plating on the metallization layer is employable. In such a case, since both surfaces are gold, when image processing is performed, it is difficult to identify both together, but the above-described image identification mark makes it easy to identify the edge of the surface conductor layer. It can be carried out.

  The image identification mark is a mark made of, for example, an insulating layer that is easier to identify with the surface conductor layer than the conductive layer. Examples of the electronic component include a SAW element, a crystal resonator, a piezoelectric resonator, and an IC.

  (2) The invention of claim 2 is characterized in that the image identification mark is provided adjacent to the surface conductor layer when the ceramic package is viewed from the cavity side.

The present invention exemplifies a preferred arrangement of image identification marks.
Here, as for the arrangement of the surface conductor layer and the conductive layer, when viewed from the cavity side (for example, the upper side), there is a case where they are adjacent to each other without any gap, but a case where there is a slight gap (that is, an image). The present invention is also effective when the gap cannot be recognized during processing.

(3) The invention of claim 3 is characterized in that the image identification mark is made of an insulating layer (for example, alumina or the like).
When a metallized layer is used as the base for the conductive layer and surface conductor layer, after forming an insulating layer on the metallized layer, each plating layer is formed on the surface of the metallized layer other than the insulating layer by electrolytic plating can do.

(4) The invention of claim 4 is characterized in that the image identification mark is colored in a color different from that of the surface conductor layer.
For example, even when a chromatic or achromatic color is applied to the surface of the conductive layer, the edge of the surface conductor layer can be easily identified.

(5) The invention according to claim 5 is characterized in that the peripheral plating layer of the surface conductor layer is formed on a metal member arranged so as to surround the opening of the cavity.
In this invention, the structure which formed the surrounding plating layer on the metal member (for example, seal ring) is employable.

(6) The invention of claim 6 is the method for manufacturing a ceramic package according to any one of claims 1 to 4, wherein the ceramic package is manufactured.
Forming a conductive pattern corresponding to the conductive layer on the surface of the ceramic green sheet corresponding to the bottom of the cavity; applying a material to be the image identification mark on the conductive pattern; and side surfaces of the cavity A step of forming a conductive pattern corresponding to the surface conductor layer on the surface of the ceramic green sheet corresponding to (that is, a convex portion constituting the side surface), a step of laminating the plurality of ceramic green sheets, and then firing. And a process.

In the present invention, a ceramic package in which an image identification mark is formed on a conductive layer can be manufactured by the above-described procedure.
Note that whichever comes first may be the order of applying the material to be the image identification mark and the process of forming the conductive pattern corresponding to the surface conductor layer.

  (7) The invention according to claim 7 uses an insulating paste (for example, a ceramic paste such as alumina) as a material for the image identification mark, and electroplats the surfaces of the conductive layer and the surface conductor layer after the firing. It is characterized by doing.

  Thereby, a plating layer can be formed on the surface of the conductive layer other than the insulating layer and the surface conductor layer, respectively.

Embodiments of the present invention will be described below with reference to the drawings.
[First Embodiment]
a) First, the ceramic package of this embodiment will be described.

  As shown in FIG. 1, the ceramic package 1 of this embodiment is used as a container (crystal oscillator package) of a crystal oscillator 3, for example, and this crystal oscillator 3 is in a recess (cavity) 5 of the ceramic package 1. In addition, the crystal oscillator 7 and the IC chip 9 are accommodated and sealed with a cover 11. The ceramic portion of the ceramic package 1 (the portion on which the insulating layer is laminated) is referred to as a substrate body 12.

  The ceramic package 1 is made of alumina, for example, and as shown in FIGS. 2 and 3, a rectangular lower ceramic plate 13 constituting the bottom of the base body 12 and a frame-shaped intermediate formed on the lower ceramic plate 13. A ceramic plate 15 and a frame-shaped upper ceramic plate 17 formed on the intermediate ceramic plate 15 are laminated and integrated. The intermediate ceramic plate 15 and the lower ceramic plate 17 form a frame portion 19 that surrounds the cavity 5.

  Specifically, on the surface (upper surface) of the lower ceramic plate 13 on the cavity 5 side, along one long side inside the frame portion 19 (that is, along the outer peripheral portion of the bottom surface of the cavity 5), FIG. The first conductive layer 21 including the inner plating layer 44 is formed so as to extend in the left-right direction, and the right end of the first conductive layer 21 extends to the upper right corner of the ceramic package 1. A similar second conductive layer 23 slightly extends obliquely from the lower left corner of the ceramic package 1.

  In particular, a part of the surface of the first conductive layer 21 including the inner plating layer 44 is covered with an insulating layer 25 made of alumina. That is, when the ceramic package 1 is viewed from the cavity 5 side (surface side), that is, when viewed from the thickness direction, the long side of the frame portion 19 is not exposed so that the central portion in the left-right direction of the first conductive layer 21 is not exposed. An insulating layer 25 is formed along the inside of the substrate by a predetermined dimension. Thereby, when viewed from the front surface side, it seems that the insulating layer 25 is formed adjacent to the inside of the frame portion 19, so the inner plating layer 44 is interposed between the frame portion 19 and the insulating layer 25. The first conductive layer 21 provided is not seen.

  In addition, a pair of overhang portions 27 and 29 are formed on one side of the short side of the intermediate ceramic plate 15 so as to form a step in the cavity 5. Are formed with intermediate conductive layers 31 and 33. Therefore, the intermediate conductive layers 31 and 33 protrude from the inner wall of the upper ceramic plate 17 when viewed from the surface side. The overhang portions 27 and 29 are formed with vias 35 and 37 for electrically connecting the intermediate conductive layers 31 and 33 to a pattern (not shown) on the bottom side.

Further, the upper ceramic plate 17 is a rectangular frame having a narrow width, and a surface conductor layer 39 is formed on a portion that becomes the surface of the substrate body 12.
As shown in FIG. 4A, the surface conductor layer 39 has a nickel plating layer 41 formed on a metallized layer 40 made of, for example, tungsten (W), and further a gold plating layer on the nickel plating layer 41. 42 is formed, and both plating layers 41 and 42 constitute a plating layer (surrounding plating layer) 43. The second conductive layer 23 and the intermediate conductive layers 31 and 33 have the same configuration.

  Similarly, in the first conductive layer 21, a plating layer (inner plating layer) 44 is formed by nickel plating and gold plating on a portion where the surface is exposed, but a portion not exposed (that is, insulating). The plating layer 44 is not formed on the surface of the layer 25.

  As shown in FIG. 1, the crystal oscillator 7 is bonded to the intermediate conductive layers 31 and 33 with a brazing material. Since the IC chip 9 has a size that fits within the frame of the intermediate ceramic plate 15, the IC chip 9 is bonded to the surface of the lower ceramic plate 13 with a brazing material below the crystal oscillator 7, and the center of the lower ceramic plate 13. It is connected to a pattern (not shown) formed in the part.

b) Next, a method for manufacturing the ceramic package 1 of the present embodiment will be described.
As shown in FIG. 5A, first, a lower green sheet 45 to be the lower ceramic plate 13 is prepared using a slurry mainly composed of alumina. Actually, in order to create a large number of lower green sheets 45 at a time, a large number of green sheets 46 as shown in FIG. 6 are created.

  Next, a W paste is screen-printed on the surface of the lower green sheet 45 to form a first conductive layer pattern 47 and a second conductive layer pattern 48 that become the first conductive layer 21 and the second conductive layer 23.

Next, an alumina paste is screen printed so as to cover a part of the first conductive layer pattern 47 to form an insulating layer pattern 49.
-Moreover, as shown in FIG.5 (b), a rectangular green sheet (not shown) is created using the slurry which has an alumina as a main component.

Next, a via hole is formed in the green sheet and filled with W paste.
Next, intermediate conductive layer patterns 53 and 55 to be the intermediate conductive layers 27 and 29 are formed by printing using a W paste at a predetermined position on the surface of the green sheet (a portion exposed when laminated).

Next, an intermediate green sheet 51 is formed by punching out the center of the green sheet so as to correspond to the intermediate ceramic plate 15.
-Furthermore, as shown in FIG.5 (c), a rectangular green sheet (not shown) is created using the slurry which has an alumina as a main component.

Next, a surface conductor layer pattern 59 to be the surface conductor layer 39 is formed at a predetermined position (frame portion) on the surface of the green sheet by printing using a W paste.
Next, an upper green sheet 57 is formed by punching out the center of the green sheet so as to correspond to the frame-shaped upper ceramic plate 17.

  The lower green sheet 45, the intermediate green sheet 51, and the upper green sheet 57 are sequentially stacked as shown in FIG. 2, and the stacked body is fired. In this firing, the portion made of the W paste becomes the metallized layer 40.

  Next, of the metallized layer 40 of the fired laminate, a portion exposed on the surface is first subjected to (electrolytic) nickel plating, and further (electrolytic) gold plating is performed on the nickel plating. Thereby, the ceramic package 1 is completed.

  c) As described above, in the present embodiment, the first conductive layer 21 is formed along the frame portion 19 at the bottom of the cavity 5 of the ceramic package 1, but on a part of the surface of the first conductive layer 21. When viewed from the surface side, the first conductive layer 21 (gold-plated) and the surface conductor layer 39 (also gold-plated) are not adjacent to each other in a predetermined section, that is, the surface conductor layer 39 An insulating layer 25 made of alumina is formed so that the inner edge can be recognized.

  As a result, even when the cavity 5 side of the ceramic package 1 is photographed to create a binarized image, the surface conductor layer 39 and the insulating layer 25 can be clearly distinguished, so that the inner edge of the surface conductor layer 39 is clearly defined. Can be recognized.

Therefore, when the crystal resonator 7 and the IC chip 9 are accommodated in the cavity 5 and fixed, the positioning accuracy is improved.
[Second Embodiment]
Next, the second embodiment will be described, but the description of the same content as the first embodiment will be omitted.

a) First, the ceramic package of this embodiment will be described.
As shown in FIG. 7, the ceramic package 71 of the present embodiment is used as, for example, a container (quartz crystal package) for the crystal resonator device 73, and the crystal resonator device 73 is the ceramic package 71. The quartz resonator 77 is accommodated in the cavity 75 and sealed with a cover 79.

  As shown in FIG. 8, the ceramic package 71 is formed by laminating a rectangular lower ceramic plate 81 constituting a bottom portion and a frame-shaped upper ceramic plate 83 formed on the lower ceramic plate 81.

  Specifically, a first conductive layer 85 is formed on the bottom portion of the lower ceramic plate 81 on the cavity 75 side so as to extend in the left-right direction in the drawing along the inner side of one long side of the upper ceramic plate 83. Yes. A similar second conductive layer 87 extends slightly in the lower left corner of the ceramic package 71.

  In particular, the surface of the central portion of the first conductive layer 85 is covered with an insulating layer 89. That is, when the ceramic package 1 is viewed from the upper surface side, it appears that the insulating layer 89 is formed adjacent to the inside of the upper ceramic plate 83, and the first ceramic plate 83 and the insulating layer 25 are provided with the first The conductive layer 85 is not seen.

  Further, first and second central conductive layers 91 and 93 are formed in a rectangular shape on the left end side of the cavity 75 in the figure, and in the center of the first and second central conductive layers 91 and 93, respectively. Convex first and second bonding conductive portions 95 and 97 (to which the crystal oscillator 77 is bonded) are formed. The first central conductive layer 91 is a part of the first conductive layer 85, and the second central conductive layer 93 is a part of the second conductive layer 87.

Further, the upper ceramic plate 83 has a rectangular frame shape with a narrow width, and a surface conductor layer 99 is formed on the surface (upper surface) thereof.
b) Next, the manufacturing method of the ceramic package 71 of this embodiment is demonstrated.

As shown in FIG. 9A, first, a lower green sheet 101 to be the lower ceramic plate 83 is prepared using a slurry mainly composed of alumina.
Next, W paste is screen-printed on the surface of the lower green sheet 101 to form the first conductive layer pattern 103 and the second conductive layer pattern 105 that become the first conductive layer 85 and the second conductive layer 87.

Next, an alumina paste is screen-printed so as to cover a part of the first conductive layer pattern 103 to form the insulating layer pattern 107.
In addition, W (for forming the first and second bonding conductive portions 95 and 97) is formed on the surfaces of the first and second conductive layer patterns 103 and 105 to be the first and second central conductive layers 91 and 93. Apply a thick paste to make it convex.

-Moreover, as shown in FIG.9 (b), a rectangular green sheet (not shown) is created using the slurry which has an alumina as a main component.
Next, a surface conductor layer pattern 109 to be the surface conductor layer 99 is formed at a predetermined position (a frame-shaped portion) on the surface of the green sheet by printing using a W paste.

Next, the upper green sheet 111 is formed by punching the center of the green sheet so as to correspond to the frame-shaped upper ceramic plate 83.
Then, the lower green sheet 101 and the upper green sheet 111 are stacked, and the stacked body is fired.

  Next, (electrolytic) nickel plating and (electrolytic) gold plating are applied to the exposed portion of the metallized layer of the fired laminate. Thereby, the ceramic package 71 is completed.

Also in this embodiment, since the inner edge of the surface conductor layer 99 can be easily recognized during image processing, the same effects as those of the first embodiment can be obtained.
In addition, this invention is not limited to the said embodiment at all, and it cannot be overemphasized that it can implement with a various aspect in the range which does not deviate from this invention.

  (1) For example, as shown in FIG. 10, in a ceramic package 127 in which three layers of ceramic plates 121, 123, and 125 are stacked as in the first embodiment, a crystal resonator 129 is accommodated in a cavity 125. The present invention can also be applied to an apparatus having a structure that does not accommodate an IC chip.

(2) Also, a layer of a color different from the surface conductor layer (color layer: achromatic color such as color or black is also possible) may be formed so that it can be easily distinguished from the surface conductor layer instead of the insulating layer. Good.
(3) Further, as shown in FIG. 4B, as the surface conductor layer 131, a metallized layer 133, a nickel plating layer 135, a silver brazing layer 137, a seal ring fitting 139, a nickel plating layer 141, and a gold plating layer 143 are provided. Sequentially laminated ones can be used.

It is explanatory drawing which shows the cross section of the crystal oscillator of 1st Embodiment. It is a perspective view which decomposes | disassembles and shows the ceramic package of 1st Embodiment. The ceramic package of 1st Embodiment is shown, (a) is the top view, (b) is AA sectional drawing of (a), (c) is BB sectional drawing of (a). (A) is a schematic diagram of the cross section of the surface conductor in 1st Embodiment, (b) is a schematic diagram of the cross section of another surface conductor. 1A and 1B show a method for manufacturing a ceramic package according to a first embodiment, in which FIG. 1A is an explanatory view of a lower green sheet, FIG. 1B is an explanatory view of an intermediate green sheet, and FIG. . It is explanatory drawing which shows the green sheet for multi-piece picking. It is explanatory drawing which shows the cross section of the crystal oscillator apparatus of 2nd Embodiment. It is a top view which shows the ceramic package of 2nd Embodiment. The manufacturing method of the ceramic package of 2nd Embodiment is shown, (a) is explanatory drawing of the green sheet for lower parts, (b) is explanatory drawing of the green sheet for upper parts. It is explanatory drawing which shows the cross section of the crystal oscillator device of other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,71 ... Ceramic package 5, 75 ... Cavity 7, 77 ... Crystal oscillator 9 ... IC chip 12 ... Substrate body 21, 85 ... First conductive layer 25, 89 ... Insulating layer 39, 99, 131 ... Surface conductor layer 43 ... Peripheral plating layer 44 ... Inner plating layer

Claims (7)

A substrate body formed by laminating a plurality of insulating layers having a front surface and a back surface;
A cavity having an opening on the surface of the substrate body and having a side surface and a bottom surface on which electronic components are mounted;
A surface conductor layer provided on the surface of the substrate body so as to surround the opening of the cavity, and provided with a peripheral plating layer on the surface;
A conductive layer provided along an outer peripheral portion of at least a part of the cavity, and having an inner plating layer composed of the same main component as the surface conductor layer on the surface;
An image identification mark provided on at least a part of the surface of the conductive layer;
A ceramic package characterized by comprising:   The ceramic package according to claim 1, wherein the image identification mark is provided adjacent to the surface conductor layer when the ceramic package is viewed from the cavity side.   The ceramic package according to claim 1, wherein the image identification mark is made of an insulating layer.   3. The ceramic package according to claim 1, wherein the image identification mark is colored in a color different from that of the surface conductor layer.   The said surrounding plating layer of the said surface conductor layer is formed on the metal member arrange | positioned so that the opening part of the said cavity may be enclosed, The any one of Claims 1-4 characterized by the above-mentioned. Ceramic package. In the manufacturing method of the ceramic package which manufactures the ceramic package of any one of the said Claims 1-5,
Forming a conductive pattern corresponding to the conductive layer on the surface of the ceramic green sheet corresponding to the cavity bottom;
Applying a material to be the image identification mark on the conductive pattern;
Forming a conductive pattern corresponding to the surface conductor layer on the surface of the ceramic green sheet corresponding to the side surface of the cavity;
Laminating a plurality of the ceramic green sheets;
A subsequent baking step,
A method for producing a ceramic package, comprising:   7. The method of manufacturing a ceramic package according to claim 6, wherein an insulating paste is used as a material for the image identification mark, and after the firing, the surfaces of the conductive layer and the surface conductor layer are electrolytically plated.