JP6290666B2 - Multi-cavity wiring board, wiring board, and manufacturing method of multi-cavity wiring board - Google Patents

Description

  The present invention relates to a multi-cavity wiring board in which a plurality of wiring board regions are arranged vertically and horizontally on a mother board, a wiring board manufactured from the multi-cavity wiring board, and a manufacturing method of the multi-cavity wiring board. is there.

  Conventionally, wiring boards used for mounting electronic components such as semiconductor elements and surface acoustic wave elements are electronic components on insulating substrates made of ceramic sintered bodies such as aluminum oxide sintered bodies and glass ceramic sintered bodies. It has a mounting part for mounting. The insulating substrate is generally composed of a square flat plate-like base portion and a square frame-like frame portion laminated on the upper surface of the base portion so as to surround the mounting portion. A frame-shaped metallized layer is formed on the upper surface of the frame part, and a metal lid is bonded to the frame-shaped metallized layer via a metal frame brazed to the frame-shaped metallized layer or mounted. The part (electronic component mounted on the mounting part) is hermetically sealed.

  Such a wiring board is generally manufactured in the form of a so-called multi-cavity wiring board in which a plurality of wiring boards are obtained simultaneously from a single large-area mother board. In the multi-cavity wiring board, a plurality of wiring board regions are arranged vertically and horizontally on a mother board made of, for example, an aluminum oxide sintered body. A dividing groove is formed in the main surface such as the upper surface of the mother board along the boundary of the wiring board region. A bending stress is applied to the mother board across the dividing groove, and the mother board is broken, so that it is divided into individual wiring boards. The dividing groove is formed, for example, by pushing a cutter blade into a predetermined position on the main surface of the unfired mother substrate.

  In recent years, a wiring board has become small, and for example, a circuit board having a size of 1.6 × 1.2 mm in vertical and horizontal dimensions in plan view is manufactured. In such a multi-piece wiring board in which wiring board areas that are remarkably miniaturized are arranged, it is difficult to provide a dividing groove using a cutter blade or the like at the boundary between adjacent wiring board areas. In view of this, a method has been proposed in which dividing grooves are formed by laser processing at the boundary between adjacent wiring board regions in the fired mother board (see Patent Document 1).

JP 2012-230945

  However, in the above-described multi-cavity wiring board, there is a possibility that the following problems occur with the downsizing of the wiring board region. That is, in such a wiring board that is remarkably miniaturized, the width of the frame portion and the frame-like metallized layer has become very narrow, and the bonding area between the upper surface of the frame portion and the frame-like metallized layer is reduced. It is coming. Therefore, for example, there has been a problem that the frame-like metallized layer is easily peeled off due to thermal stress at the time of joining the metal lid.

Such a defect is likely to occur particularly when the dividing grooves are formed by laser processing. This is considered due to the following reasons. That is, if the dividing groove is formed with a cutter blade, the metallized layer is formed around the inner surface of the dividing groove as the cutter blade is pushed in, and the ease of peeling may be reduced. On the other hand, when the division grooves are formed by laser processing, the possibility of obtaining such an effect is small. Therefore, peeling of the frame-shaped metallized layer is likely to occur.

A multi-piece wiring board according to one aspect of the present invention is provided with a plurality of wiring board regions, and a mother board having a main surface including a dividing groove provided along an outer periphery of the wiring board region, The main surface of the mother board is provided with a frame-like metallization layer provided along the division grooves, and the frame-like metallization layer has an outer end portion that touches the division grooves bites into the mother board. cage, in the region bites into the mother substrate, the thickness closer to the dividing grooves that have thicker.

Wiring board of one embodiment of the present invention, the multi-cavity circuit board, ing is divided for each of the wiring substrate region.

One method for producing a multi-piece wiring board aspect of the present invention includes the steps of preparing a ceramic green sheet having a plurality of wiring substrate areas with and has an upper surface is arranged, the upper surface of the ceramic green sheet And a step of applying a metallization paste in a frame shape along the boundaries of the plurality of wiring board regions, and a step of forming dividing grooves along the respective boundaries of the plurality of wiring board regions, in the step of applying the metallization paste, Ru said metallizing paste was bite into the ceramic greensheet in the boundary.

According to the multi- cavity wiring board of one aspect of the present invention, a plurality of wiring board regions are arranged, and a mother board having a main surface including a dividing groove provided along the outer periphery of the wiring board region; The main surface of the mother board is provided with a frame-like metallized layer provided along the dividing groove, and the frame-like metallized layer bites into the mother board at the outer end in contact with the dividing groove . Since the thickness of the region that has penetrated into the groove increases as it is closer to the dividing groove, the bonding area between the frame-like metallized layer and the mother substrate (frame portion) can be increased to increase their bonding strength. A large anchor effect can be obtained. That is, the outer end portion of the frame-like metallized layer that is particularly prone to large thermal stress is firmly joined to the frame portion. Therefore, it is possible to provide a multi-piece wiring board capable of manufacturing a wiring board in which the frame-like metallized layer is prevented from peeling off from the frame part.

  According to the wiring board of one aspect of the present invention, since the multi-piece wiring board having the above-described configuration is divided for each wiring board region, the wiring in which the frame-like metallized layer is prevented from being peeled off from the frame part. A substrate can be provided.

  According to the method for manufacturing a multi-piece wiring board of one aspect of the present invention, since the above steps are included, the joint area between the frame-like metallized layer and the frame part can be increased, and the outer end part of the frame-like metallized layer It is possible to easily form a structure that is firmly joined to the outer periphery of the frame portion. Therefore, it is possible to easily manufacture a multi-piece wiring substrate capable of manufacturing a wiring substrate in which the frame-like metallized layer is prevented from being peeled from the frame portion.

(A) is a top view which shows the multi-piece wiring board of embodiment of this invention, (b) is sectional drawing in the X-X 'line | wire of (a). It is a top view which shows the wiring board of embodiment of this invention. It is a cross-sectional enlarged view which shows the principal part of the wiring board of embodiment of this invention. FIG. 4 is an enlarged cross-sectional view illustrating a main part of a wiring board according to a modified example of FIG. 3. It is a top view which shows the principal part in the modification of the multi-cavity wiring board shown in FIG. (A) And (b) is a top view which shows the wiring board of the modification of FIG. 2, respectively. (A)-(c) is sectional drawing which shows the principal part in the manufacturing method of the multi-cavity wiring board of embodiment of this invention in order of a process. (A) And (b) is sectional drawing which shows the principal part in the manufacturing method of the multi-cavity wiring board of embodiment of this invention in order of a process. It is a cross-sectional enlarged view which shows the principal part in the other modification of FIG.

  A multi-cavity wiring board, a wiring board, and a manufacturing method of the multi-cavity wiring board of the present invention will be described with reference to the accompanying drawings.

  FIG. 1A is a top view illustrating a multi-piece wiring board according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line X-X ′ in FIG. 2 is a top view showing a wiring board obtained from the multi-cavity wiring board shown in FIG.

  A plurality of wiring board regions 101 are arranged on the mother board 100 to basically form a multi-piece wiring board. In the example of the embodiment, the mother board 100 includes a base portion 102 and a frame portion 103 stacked on the base portion 102. The wiring board region 101 is provided with a mounting portion 104 that accommodates electronic components. In addition, a frame-like metallized layer 105 is provided so as to surround the mounting portion 104 in plan view.

Divided grooves 110 are formed on the upper surface of the mother board 100 along the boundary 116 of the wiring board region 101. The multi-cavity wiring board may have a larger number of wiring board regions 101 arranged vertically and horizontally.

The mother board 100 is basically formed by a flat base portion 102 and a frame portion 103 provided on the base portion. The frame portion 103 has a plurality of openings (no symbol). A concave mounting portion 104 is formed by this opening and the upper surface of the base 102 exposed inside the opening. That is, the frame portion 103 has a plurality of frame-like portions that form the mounting portion 104.

Such a multi-piece wiring board (mother board 100) is divided along the boundary 116 of the wiring board region 101, and for example, a piece of wiring board 101a as shown in FIG. 2 is manufactured. The wiring board 101a to be manufactured is a frame-shaped upper board (on the upper surface of a square flat board-like lower board (base 102 of the mother board 100)).
The frame-like metallized layer 105, the wiring conductors 108, and the like are basically provided on an insulating substrate (without reference numeral) in which the frame portion 103) of the mother substrate 100 is laminated.

The base substrate 100 is a ceramic sintered body such as an aluminum oxide sintered body, a glass ceramic sintered body, an aluminum nitride sintered body, a silicon carbide sintered body, a silicon nitride sintered body, or a mullite sintered body. It is formed by.

  Further, a margin area (not shown) may be provided on the outer periphery of the mother board 100 so as to surround the plurality of wiring board areas 101 arranged. The disposal allowance area is provided for facilitating handling of the multi-piece wiring board.

The mother board 100 is manufactured by integrally firing a plurality of ceramic insulating layers. That is,
A plurality of ceramic green sheets are manufactured by adding a suitable organic solvent and a binder to a raw material powder containing a glass component such as aluminum oxide and silicon oxide and forming into a sheet shape. Next, a part of the plurality of ceramic green sheets is punched and formed into a frame shape, and then the frame-shaped ceramic green sheets are stacked on the flat ceramic green sheets. Thereafter, if this laminate is integrally fired, a mother substrate 100 in which a plurality of ceramic insulating layers are laminated can be manufactured. In this case, a part of the ceramic green sheets is punched to provide an opening, and the ceramic green sheet having the opening (to become the frame 103) is laminated on the upper layer. For example, the mother substrate 100 having a recess on the upper surface can be manufactured.

The plurality of wiring board regions 101 arranged on the mother board 100 have a mounting part 104 for electronic components (not shown) in the center or the like, and each is a region that becomes an individual wiring board 101a. Each wiring board region 101 has a form in which the frame portion 103 is laminated on the upper surface of the flat base 102 as described above. The frame part 103 is for protecting the electronic components housed in the mounting part 104.

The electronic parts housed in the mounting unit 104 include various types of elements such as piezoelectric vibration elements such as crystal vibration elements, surface acoustic wave elements, semiconductor elements such as semiconductor integrated circuit elements (ICs), capacitive elements, inductor elements, and resistors. Mention electronic components.

A wiring conductor 108 is formed on the inside and the surface of the mother board 100 from the mounting portion 104 to the lower surface of the mother board 100. A portion of the wiring conductor 108 formed on the lower surface of the mother board 100 is located, for example, on the outer peripheral portion of the lower surface of each wiring board region 101. Of the wiring conductors 108, those formed inside the mother board 100 are in the form of a through conductor (so-called via conductor or the like), an internal wiring layer, or the like. By electrically connecting the electronic component mounted on the mounting portion 104 to the wiring conductor 108 formed in the mounting portion 104, the electronic component is electrically connected to an external electric circuit via the wiring conductor 108. .

The wiring conductor 108 is, for example, copper, silver, palladium, gold, platinum, tungsten, molybdenum,
Made of a metal material such as manganese. If the wiring conductor 108 is made of, for example, molybdenum, a ceramic green sheet that serves as a base substrate 100 is a metal paste (metallized paste) (not shown) manufactured by adding an organic solvent and a binder to molybdenum powder. It can be formed by coating in a predetermined pattern and firing simultaneously.

Various electronic components as described above are accommodated in the wiring board 101a manufactured by dividing the multi-piece wiring board having such a configuration into pieces. An electronic device in which electronic components are housed in the wiring board 101a is mounted as a component in various electronic devices. For example, if the electronic component is an oscillating element such as a piezoelectric vibration element, the electronic device is used in a communication device such as a mobile phone or a car phone, or in an electronic device such as a computer or an information device such as an IC card. Used as a reference oscillator.

  In order to divide the mother board 100, dividing grooves 110 are formed on the upper and lower surfaces of the mother board 100 along the boundary 116 of the wiring board region 101. By applying stress to the mother board 100 at the portion where the dividing groove 110 is formed (border 116 of the wiring board region 101) and breaking the mother board 100 in the thickness direction, the mother board 100 becomes a piece of the wiring board 101a. Will be divided.

  The dividing groove 110 becomes the base 102 after printing and applying a metallization paste that becomes the frame-like metallization layer 105 on the entire upper surface of each wiring board region 101 of a ceramic green sheet (not shown) that becomes the frame 103, for example. After a ceramic green sheet (not shown) is laminated on a ceramic green sheet (not shown) to obtain a laminated body, a laminated body is obtained, and then a cutter blade or a laser beam is placed on the boundary 116 of the adjacent wiring board region 101 on the upper surface side of the laminated body. It is manufactured by making a notch with etc.

The mother board 100 is, for example, a flat plate having a side length of about 60 to 120 mm in plan view. The width of a margin area (not shown) formed on the outer peripheral portion of the mother substrate 100 is about 5 to 10 mm. As a method of dividing each wiring board region 101 of the mother board 100 into pieces for a multi-piece wiring board, for example, a method of pressing the mother board 100 from above and below with a roller or the like can be cited. Specifically, the mother substrate 100 is sandwiched between the transfer roller and the pressing roller from above and below, and the transfer roller serves as a fulcrum and the pressing roller serves as an action point along the dividing groove 110 in the thickness direction of the mother substrate 100. A method is adopted in which pressure is applied, and the mother substrate 100 is broken in the thickness direction by this pressure and divided into each wiring substrate 101a.

A frame-like metallized layer 105 is formed on the upper surface of each wiring board region 101 in contact with the dividing groove 110. Then, as will be described later, the metal lid 113 is joined directly to the frame-shaped metallized layer 105 or via the metal frame 115 brazed to the frame-shaped metallized layer 105, so that the mounting unit 104 (mounted on the mounting unit) Electronic component) is hermetically sealed. In the example of FIGS. 1 and 2, the frame-like metallized layer 105 covers the entire upper surface of the frame portion 103. The frame-like metallized layer 105 does not necessarily need to cover the entire upper surface of the frame part 103, but if the frame-like metallized layer 105 is provided on the entire upper surface of the frame part 103, the metal lid This is advantageous in terms of securing the bonding area 113.

The frame-like metallized layer 105 is made of a metal such as tungsten or molybdenum. For example, if the frame-like metallized layer 105 is made of a molybdenum metallized layer, a ceramic powder that forms the frame 103 is made of a molybdenum powder and a metallized paste produced by adding an organic solvent, a binder, or the like to the ceramic powder. It can be formed by printing in a predetermined pattern on the upper surface of the sheet.

In the example of this embodiment, a plating layer 112 such as a nickel plating layer and a gold plating layer is deposited on the upper surface of the frame-like metallized layer 105.

The plating layer 112 is formed, for example, for preventing the oxidative corrosion of the frame-like metallized layer 105 and for improving the wettability of the brazing material 114 at the time of brazing or the like and for enhancing the bonding strength. The plating layer 112 preferably has a two-layer structure (not shown) in which, for example, a nickel plating layer is formed on the lower side and a gold plating layer is formed on the upper side. Here, in terms of cost, the plating layer 112 is preferably formed thin, the nickel plating layer is formed to have a thickness of about 2 to 20 μm, and the gold plating layer is formed to have a thickness of about 0.1 to 1.0 μm. The plating layer 112 can be formed by, for example, supplying a plating deposition current to the portion to be plated (the surface of the frame-like metallized layer 105) in a plating solution and performing electrolytic plating.

For example, as shown in FIG. 1, the frame-shaped metallized layer 105 has an outer end portion in contact with the dividing groove 110 biting into the mother substrate 100. With such a structure, the bonding area between the frame-shaped metallized layer 105 and the frame part 103 can be increased, and the bonding strength between the frame-shaped metallized layer 105 and the frame part 103 can be increased. In other words, the outer peripheral portion of the frame-like metallized layer 105, in particular, where thermal stress tends to act greatly, is firmly bound to the frame portion 103. Therefore, it is possible to provide a multi-piece wiring board capable of manufacturing the wiring board 101a in which the frame-like metallized layer 105 is prevented from being peeled off from the frame part 103.

Note that the above-described thermal stress is generated due to a difference in coefficient of thermal expansion between the frame 103 and the metal lid, for example, when a metal lid (not shown in FIG. 1) is bonded onto the frame 103. . Actually, the metal lid is joined to the frame portion 103 to the individual wiring board 101a. Further, the metal lid is actually bonded to the frame-like metallized layer 105 provided on the upper surface of the frame portion 103 via a bonding material such as a brazing material (not shown in FIG. 1). Therefore, thermal stress is generated between the frame-like metallized layer 105 of the wiring board 101a and the metal lid.

In addition, a frame-like metallized layer 105 whose outer end portion in contact with the dividing groove 110 bites into the mother substrate 100.
As the shape, for example, as shown in FIG. 1B, an example in which the lower part of the outer end protrudes downward in an arc shape can be given. The arc-shaped protruding portion of the frame-like metallized layer 105 bites into the mother board 100 (frame part 103) on the outer periphery of the wiring board region 101.

Note that the frame-like metallized layer 105 can also be regarded as having a thickness greater in the portion near the boundary 116 of the wiring board region 101 than in other portions. In this case, the thickness (projection height) of a relatively thick portion at the outer end portion (boundary portion of the wiring board region 101) of the frame-like metallized layer 105 is set to about 10 to 30 μm, for example. Further, the thickness at the outer end of the frame-like metallized layer 105 is set to about 15 to 40 μm, for example. The dividing groove 110 is divided into two by cutting a portion where the thickness of the outer end portion of the frame-like metallized layer 105 is thick. A part of the frame-like metallized layer 105 is exposed on the surface in the dividing groove 110 at the outer edge of the upper surface of each wiring board region 101.

The frame-like metallized layer 105 whose outer end bites into the mother board 100 is, for example, as described above, where the thickness of the frame-like metallized layer 105 is the outer end part (the part along the boundary 116 of the wiring board region 101). What is necessary is just to make it thicker than another part so that this thicker part may be buried in the mother board | substrate 100 (frame part 103). Specifically, when the metallization paste is applied to the ceramic green sheet to be the mother substrate 100, the thickness is made thicker at the portion along the boundary 116 of the wiring board region 101 than at the other portions. What is necessary is just to make a thicker part bite into a ceramic green sheet by means, such as pressurization. The printing thickness can be appropriately adjusted depending on, for example, the distance between the screen printing plate (plate making) and the ceramic green sheet, the viscosity of the metallizing paste, the number of times of printing, and the like.

FIG. 3 shows the main part of the wiring board 101a in a state where the metal lid 113 is bonded to the upper surface of the frame-like metallized layer 105 formed in the frame part 103. FIG. 3 is an enlarged cross-sectional view showing a main part of the wiring board of the embodiment. In FIG. 3, the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals.

As shown in the example of FIG. 3, the frame-like metallized layer 105 includes a lower layer 106 located in the insulating substrate of the wiring substrate 101 a at the outer end, and an upper layer 107 provided on the lower layer 106. You may go out. Since the insulating substrate of the wiring substrate 101a is obtained by dividing the mother substrate 100 into pieces, the frame-shaped metallized layer 105 is assumed to include the lower layer 106 and the upper layer 107 in the multi-piece wiring substrate. The lower layer 106 bites into the mother substrate 100.

In this case, as described above, the thickness at the outer end portion is thicker than the other portions, and it is easier to form the frame-like metallized layer 105 in which the protruding portion due to the difference in thickness bites into the mother substrate 100. In addition, the amount of biting can be easily adjusted. Therefore, the lower layer 106 serving as the outer end portion of the frame-shaped metallized layer 105 can be more effectively formed as a metallized layer for restraining the outer periphery of the frame 103. Further, an upper layer 107 for bonding the metal lid 113 to the upper surface of the frame-like metallized layer 105.
Can be effectively formed as a bonding surface having a large area.

FIG. 4 is an enlarged cross-sectional view showing a wiring board according to a modification of FIG. 4, parts similar to those in FIG. 3 are denoted by the same reference numerals. In the example of FIG. 4, a metal frame 115 is bonded to the upper surface of the frame-shaped metallized layer 105, and a metal lid 113 is bonded to the upper surface of the metal frame 115. The example of FIG. 3 and the example of FIG. 4 have the same configuration except that the metal lid 113 is bonded to the frame-like metallized layer 105 (wiring substrate 101a) via the metal frame 115.

3 and 4, the lower layer 106 of the frame-like metallized layer 105 is formed such that the outer end (lower part) in contact with the dividing groove 110 is bitten into the insulating substrate (mother substrate 100). The upper layer 107 of the frame-shaped metallized layer 105 covers the entire upper surface of the lower layer 106 and covers the entire upper surface of the frame-shaped portion (frame portion 103) of the insulating substrate.

Here, the lower layer 106 of the frame-like metallized layer 105 is thus an insulating substrate (wiring board region 101).
For example, as described above, the frame-like metallized layer 105 may include the lower layer 106 and the upper layer 107 as a multi-piece wiring board. That is, first, the first metallizing paste having a narrow width that becomes the lower layer 106 is printed along the entire circumference of the boundary 116 of the wiring board region 101 of the ceramic green sheet (mother board 100). Next, the second metallization paste having a wide width to be the upper layer 107 is printed on the entire periphery of the frame part 103 of the wiring board region 101 while covering the printed first metallization paste. Thereafter, the first metallization paste and the second metallization paste are simultaneously pressurized and fired simultaneously, whereby the lower layer 106 is embedded in the frame part 103 and the upper layer 107 is formed flat on the upper surface of the frame part 103. A frame-like metallized layer 105 can be formed.

The lower layer 106 preferably has a thickness after firing of about 10 to 30 μm. Hereinafter, the multi-cavity wiring board will be described. When the thickness of the lower layer 106 is less than 10 μm, the effect of constraining the outer end of the frame-shaped metallized layer 105 to the outer periphery of the frame 103 is reduced by the area where the frame-shaped metallized layer 105 is bitten. There is a possibility that the effect of suppressing peeling of the frame-like metallized layer 105 due to thermal stress such as time may be reduced. In addition, when the thickness of the lower layer 106 exceeds 30 μm, the volume as a metallized layer that bites the lower layer 106 into the frame portion 103 is increased, and the frame portion 103 (when the lower layer 106 is bitten into the frame portion 103 ( Ceramic green sheet) may be deformed or cracked. Therefore, the thickness of the lower layer 106 is preferably about 10 to 30 μm. And it forms so that the thickness of the upper layer 107 in the frame-shaped metallized layer 105 after baking may be set to about 5-10 micrometers. Therefore, in this case, the total thickness of the frame-like metallized layer 105 in the region where the lower layer 106 and the upper layer 107 overlap in plan view is about 15 to 40 μm.

The frame-like metallized layer 105 may contain ceramic particles in at least the lower layer 106 at the outer end. In this case, the bonding strength between the lower layer 106 of the frame-like metallized layer 105 and the frame portion 103 (ceramic) can be increased. That is, during firing of the laminate that will be the mother substrate 100, the ceramic particles contained in the metallization paste that will be the lower layer 106 and the ceramic green sheet (laminate) that will be the frame portion 103 react with each other, thereby reducing the bonding strength. Can be bigger.

For example, in the case of a paste for metallization printed on a laminate that is a mother substrate 100 (an insulating substrate of a piece of wiring substrate 101a) made of an aluminum oxide sintered body, tungsten (W), molybdenum (Mo) An organic solvent and a solvent are added to a refractory metal powder such as aluminum powder and a ceramic powder such as aluminum oxide to obtain a paste. The ceramic powder added at this time may be the same as the ceramic powder contained in the ceramic green sheet used as the mother substrate 100, for example. The bonding strength between the lower layer 106 and the frame portion 103 can be increased by setting the content of ceramic particles in the lower layer 106 to about 5 to 20 vol%, for example.

Then, the prepared metallizing paste for the lower layer 106 is applied to the surface of the ceramic green sheet by screen printing or the like, and then the ceramic green sheet is appropriately laminated and fired at a temperature of 1450 to 1700 ° C. in a reducing atmosphere. To do. Through the above steps, part of the glass component interposed between the aluminum oxide crystal particles of the aluminum oxide sintered body is transferred between the metal particles of the refractory metal, and the aluminum oxide particles (sintered powder of the above powder) The melting point metal is bonded via a glass component, and is fixed to a frame portion 103 (mother substrate 100) made of an aluminum oxide sintered body. At this time, since the lower layer 106 contains ceramic particles, not only a part of the glass component interposed between the aluminum oxide crystal particles of the frame 103 (aluminum oxide sintered body), but also the lower layer 106. This is because the ceramic particles in the metallization paste to be reacted with the ceramic green sheet to be the frame portion 103 contributes to the bonding between the frame portion 103 and the lower layer 106.

On the other hand, it is preferable that the upper layer 107 does not contain ceramic particles. When the upper layer 107 does not contain ceramic particles, when the plating layer 112 such as nickel or gold is deposited on the upper layer 107, the deposition is performed better (easy and strong). . Upper layer 107
Even when the ceramic particles are not contained in the metal, the bonding strength between the upper layer 107 and the frame 103 (ceramic) is supplemented by a part of the glass component contained in the frame 103. Even if a part of the glass component moves into the upper layer 107, the glass component hardly crawls up on the upper surface of the upper layer 107 that does not contain ceramic particles. Therefore, the upper surface of the frame-like metallized layer 105 is formed with a large amount of metal components.

However, the frame-like metallized layer 105 may contain ceramic particles in both the lower layer 106 and the upper layer 107 at the outer end. In this case, it is preferable that the content of ceramic particles in the lower layer 106 is larger than the content of ceramic particles in the upper layer 107. In this case, the difference in shrinkage between the ceramic green sheet (the mother substrate 100 including the frame portion 103) and the metallization paste (the frame-like metallized layer 105) during firing is further reduced. Therefore, it is possible to more effectively suppress the sealing surface (frame-like metallized layer 105) of the wiring board region 101 from warping due to the difference in shrinkage rate. That is, since the upper layer 107 covering the entire upper surface of the frame portion 103 serving as the sealing surface also contains ceramic particles, the ceramic green sheet serving as the frame portion 103 and the metallizing paste serving as the upper layer 107 The shrinkage rate during firing is closer. As a result, the metallizing paste that becomes the upper layer 107 is restrained from constraining the ceramic green sheet that becomes the frame portion 103 in the compression direction or the contraction direction, and the sealing surface of the wiring board region 101 is hardly warped.

Further, the bonding strength between the lower layer 106 of the frame-like metallized layer 105 and the frame portion 103 (ceramic) can be further increased. That is, the bonding strength between the upper layer 107 and the frame portion 103 is set so that the ceramic particles and the frame portion included in the metallization paste that becomes the lower layer 106 when the laminate that becomes the mother substrate 100 is fired, like the lower layer 106. The size can be increased by reacting with the ceramic green sheet (laminate) to be 103. When the content of the ceramic particles in the lower layer 106 is, for example, about 5 to 20 vol% as described above, the content of the ceramic particles in the upper layer 107 is about 2 to 5 vol%. The bonding strength between the lower layer 106 and the frame portion 103 and between the upper layer 107 and the frame portion 103 can be increased without sacrificing the adherence. At the same time, since the upper layer 107 has a smaller ceramic particle content than the lower layer 106, the surface area of the ceramic particles exposed on the surface of the upper layer 107 is reduced, and the glass component rises on the upper surface of the upper layer 107. It is suppressed. Therefore, the upper surface of the frame-like metallized layer 105 is formed in a state where the metal component is relatively large, and the plating layer 112 such as nickel or gold is satisfactorily applied.

In the case of such a configuration, the first metallization paste that becomes the lower layer 106 together with the sintering of the refractory metal powder also in the joining of the lower layer 106 and the upper layer 107 at the outer end portion of the frame-shaped metallized layer 105. A part of the glass component contained in the ceramic particles contained therein and a part of the glass component contained in the ceramic particles contained in the second metallization paste to be the upper layer 107 are formed between the lower layer 106 and the upper layer 107. Contributing to the bonding, the bonding strength between the lower layer 106 and the upper layer 107 of the frame-like metallized layer 105 can also be made strong.

In the present embodiment, the lower layer 106 is thicker as it is closer to the outer end of the frame-like metallized layer 105. In this case, as the thickness of the lower layer 106 increases, the lower layer 106 bites more into the frame portion 103 and is bonded more firmly. Therefore, the peeling of the frame-shaped metallized layer 105 is more effectively suppressed even at the outer peripheral portion of the frame-shaped metallized layer 105 where the thermal stress acts more greatly. Details are as follows.

That is, when the metal lid 113 is joined to the frame-shaped metallized layer 105 via the metal frame 115 brazed to the frame-shaped metallized layer 105 or directly to the frame-shaped metallized layer 105 via the brazing material 114, the metal lid 113 Due to the thermal stress at the time of bonding, a thermal stress acts such that the bonded metal lid 113 pulls the frame-like metallized layer 105 toward the center of the insulating substrate. At this time, the outer peripheral portion of the frame-like metallized layer 105 is made thicker by the outer periphery of the frame portion 103 due to the thicker thickness of the outer-end portion of the frame-like metallized layer 105 to which the stress is applied. It can be firmly restrained.

Further, the volume as the frame-like metallized layer 105 can be further reduced while ensuring the thickness of the lower layer 106 at the outer end portion (that is, the depth of biting into the frame portion 103). For this reason, in the configuration including the frame-like metallized layer 105 whose outer end bites into the frame portion 103, the thermal stress is further reduced, and the deformation and cracking of the frame portion 103 (ceramic green sheet) due to the thermal stress are further reduced. It can be effectively suppressed.

And the frame-like metallized layer 105 has a stronger bonding strength at the outer end,
A structure in which the sealing surface to which the metal lid 113 and the metal frame 115 are joined is formed with good flatness can be realized. The flat sealing surface can suppress the volume of the brazing material 114 when the metal lid 113 or the metal frame 115 is joined to the frame-like metallized layer 105, that is, the brazing material has an uneven shape on the sealing surface. The effect is that 114 volumes are not wasted. Therefore, when the metal lid 113 is joined to the frame-like metallized layer 105 by the brazing material 114 such as silver brazing, a sealing structure with excellent hermetic reliability can be realized while suppressing an increase in member cost.

The dividing grooves 110 formed on the mother substrate 100 are formed by, for example, laser processing. Laser processing may be performed on the mother substrate 100 after firing, or may be performed on the ceramic green sheet before firing. In this case, the processing accuracy of the dividing groove 110 is high, and it is possible to cope with a small wiring board 101a. Further, the frame portion 103 (
A frame-like metallized layer 105 having excellent bonding strength to the mother substrate 100 and individual insulating substrates) can be realized.

That is, as described in the description of the background art, since laser processing is non-contact processing, a cutter blade or the like is pushed into the outer end portion of the frame-like metallized layer 105 to deform the outer end portion of the frame portion 103 ( Compared with the case where the dividing groove 110 is formed, a starting point of peeling can be easily formed at the outer end portion of the frame-like metallized layer 105. Therefore, the frame-like metallized layer 105 tends to be easily peeled off. On the other hand, since the multi-piece wiring board and the wiring board of the present embodiment have the frame-like metallized layer 105 having the above-described configuration, peeling of the frame-like metallized layer 105 can be effectively suppressed. Specifically, even when the frame 103 is not deformed as in the case of forming the dividing groove 110 by the cutter blade, the outer end of the frame-like metallized layer 105 is the base substrate 100 (insulating the frame 103 and the individual pieces). Therefore, the peeling of the frame-shaped metallized layer 105 can be effectively suppressed. Therefore, the frame-like metallized layer 105 to which the metal lid 113 and the metal frame 115 are bonded to the upper surface
Can be effectively formed as a large-area joint surface with no deformation at the outer end and excellent joint strength.

In order to form the dividing grooves 110 on the mother substrate 100 by laser processing, for example, a fundamental laser beam (hereinafter simply referred to as a laser) excited by a solid laser (for example, a YAG laser) is formed on the frame-like metallized layer 105. And a V-shaped dividing groove 110 is formed at the boundary 116. Specifically, a laminated body in which a plurality of ceramic green sheets are laminated is manufactured, and a plurality of wiring board regions 101 are arranged vertically and horizontally in the laminated body, and a laser is applied to the boundary 116 of the wiring board region 101. Irradiation may form the dividing groove 110. Alternatively, the mother substrate 100 may be subjected to processing similar to the processing performed on the stacked body.

In this case, as shown in FIG. 5, a positioning pattern 117 may be formed in the same marginal position as the lower layer 106 in the disposal margin region on the outer periphery of the stacked body. FIG. 5 is a top view showing a main part in a modification of the multi-cavity wiring board shown in FIG. 5, parts similar to those in FIG. 1 are denoted by the same reference numerals. The positioning pattern 117 is formed by printing or the like at the same time that the metallizing paste that becomes the lower layer 106 is formed on the ceramic green sheet that becomes the frame portion 103 by screen printing or the like so that the laser can surely divide the lower layer 106 into two. It has been done. As a result, even if the entire surface of the lower layer 106 is the frame-like metallized layer 105 covered with the upper layer 107, the position of the lower layer 106 can be estimated, and therefore the laser is irradiated to the lower layer 106 with higher positional accuracy and reliability. The frame-like metallized layer 105 including the lower layer 106 can be divided into two. At this time, since the positioning pattern 117 is a single layer and is formed thinner than the frame-like metallized layer 105, biting into the mother substrate 100 due to pressurization is suppressed. Therefore, since the depth of the dividing groove 110 is reduced by the laser processing by the thickness of the positioning pattern 117, there is also an effect that it is possible to secure the strength of the margin area.

The mother substrate 100 is formed of a ceramic sintered body mainly composed of alumina, silicon nitride, aluminum nitride, silicon carbide, mullite, ferrite, glass ceramics, or the like as described above. With such a material, a plurality of ceramic green sheets having a thickness of, for example, about 25 to 150 μm are stacked, and formed to have a thickness of, for example, 150 to 500 μm. The mother substrate 100 has Mg, Mn, Co, Cr as components for increasing the laser absorption rate.
At least one metal oxide selected from the group consisting of Cu, Ni, and Fe may be included.

  As described above, the mother substrate 100 may further include a plating layer 112 provided on the exposed surface of the frame-like metallized layer 105. This is advantageous for suppressing the oxidation of the frame-like metallized layer 105, the wettability of the brazing material 114, and the like.

Further, the dividing groove 110 is formed by laser processing, and a part of the lower layer 106 and the upper layer 107 of the frame-shaped metallized layer 105 is exposed on the inner surface of the dividing groove 110, and the ceramic particles are contained in the lower layer 106 When the amount is relatively large, for example, as shown in FIGS. 3 and 4, the thickness of the plating layer 112 has a structure that is thinner in the lower layer 106 than in the upper layer 107 in the frame-like metallized layer 105. . In the case of such a structure, even when the size of the wiring board 101a is reduced and the width of the dividing groove 110 formed at the boundary 116 of the adjacent wiring board area 101 is reduced, the frame of the adjacent wiring board area 101 is reduced. Between the adjacent metallized layers 105 across the dividing groove 110,
It is suppressed that the plating layers 112 adhere to each other. Therefore, when the mother board 100 is divided into individual pieces along the dividing groove 110, occurrence of burrs and chips on the wiring board 101a is suppressed.

That is, when laser processing is performed from the upper surface of the frame-like metallized layer 105 when forming the dividing groove 110, the V-shaped dividing groove 110 is formed in a state of non-contact processing and the frame portion 103 is not deformed. The lower layer 106 is exposed on the 110 side. Since the lower layer 106 contains a relatively large amount of ceramic particles, a part of the glass component in the ceramic particles crawls up to the surface of the lower layer 106 exposed on the dividing groove 110 side by heat during laser processing, and the upper layer 107 Formed more. When the plating layer 112 is deposited on the mother substrate 100 in this state, the plating layer 112 is hardly formed on the surface of the lower layer 106 partially covered with the glass component.

As a result, as shown in the cross-sectional views of FIGS. 3 and 4, the plating layer 112 has a structure in which the lower layer 106 of the frame-like metallized layer 105 is thinner than the upper layer 107, so that the adjacent wiring board The adhesion of the frame-like metallized layer 105 in the region 101 adjacent to each other across the dividing groove 110 is suppressed. Since the dividing groove 110 is V-shaped and the interval between the lower layers 106 is smaller than the interval between the upper layers 107 (gap between the dividing grooves 110) in the adjacent wiring board region 101, such a structure is
This is effective in suppressing the adhesion of the frame-like metallized layer 105 between the wiring board regions 101.

As described above, the wiring board 101a is manufactured by dividing the multi-piece wiring board having any one of the above-described configurations into the wiring board regions 101. Thereby, it is possible to provide the wiring board 101a in which the bonding area between the frame-like metallized layer 105 and the frame part 103 is increased and the bonding strength between the frame-like metallized layer 105 and the frame part 103 is increased. That is, directly on the frame-like metallized layer 105 or on the metal frame 11
Even when the metal lid 113 is bonded via the thermal stress acting on the metal lid 113 pulling the frame-like metallized layer 105 toward the center of the insulating substrate, the frame-like metallized layer 105 The outer periphery of the frame-like metallized layer 105 is constrained to the outer periphery of the frame portion 103 by the portion that has been bitten. Therefore, the wiring substrate 101a in which the frame-like metallized layer 105 is prevented from being peeled off from the frame portion 103 can be obtained.

The frame-like metallized layer 105 is formed, for example, on the entire surface of the frame portion 103, and a lower layer 106 that bites into the mother substrate 100, and an upper layer 107 that covers the upper surface of the lower layer 106 and the frame portion 103. It consists of and. In the example of the wiring board 101a shown in FIG. 2, the formation position of the lower layer 106 is indicated by a broken line. The inner circumference of the lower layer 106 is located at the position of this broken line. The lower layer 106 is formed along the outer periphery of the frame portion 103 outside the broken line. For example, the width of the lower layer 106 in the individual wiring board 101a after firing is formed to be about 30 to 80 μm. In consideration of misalignment due to the formation of the dividing grooves 110 and disappearance of the frame-like metallized layer 105 (metallized paste) due to laser processing, the width of the lower layer 106 is preferably about 50 to 80 μm.

Further, the lower layer 106 does not necessarily need to be continuously formed along the outer periphery of the frame portion 103 of the wiring board region 101, and may have a form as shown in FIG. 6, for example. 6A and 6B are top views showing modifications of the wiring board shown in FIG. 6A and 6B show an example in which the frame-like metallized layer 105 is composed of a lower layer 106 and an upper layer 107. FIG. FIG.
In FIG. 2, the same parts as those in FIG.

In the example of FIG. 6A, the lower layer 106 is formed on the four sides excluding the region (corner portion) in contact with the castellation 109. Thereby, deformation of the small-diameter hole constituting the castellation 109 can be more effectively suppressed.

In the example of FIG. 6B, the lower layer 106 is discontinuously formed along the outer periphery of the frame portion 103. In this case, the anchor effect at the outer end portion of the frame-like metallized layer 105 can be effectively obtained while suppressing the amount of the frame-like metallized layer 105 that bites into the mother substrate 100.
That is, since the volume of the frame-like metallized layer 105 embedded in the frame portion 103 having a relatively narrow width is suppressed, for example, the possibility that the frame portion 103 is deformed can be further reduced. In this case, it is preferable that the lower layer 106 is located at or near the corner portion of the frame-shaped metallized layer 105 where peeling tends to occur.

Further, the same effect can be obtained for the individual distribution board 101a when the same configuration as that of the multi-piece wiring board is included. For example, when the lower layer 106 contains ceramic particles, the bonding strength between the lower layer 106 of the frame-like metallized layer 105 and the frame portion 103 (ceramic) can be increased as described above. Further, when ceramic particles are contained in both the lower layer 106 and the upper layer 107, deformation of the upper surface portion of the frame portion 103 during firing is suppressed, and warpage of the sealing surface of the wiring board region 101 is suppressed. In addition, the wiring board 101a having excellent hermetic sealing property can be realized.

When the lower layer 106 is closer to the outer periphery of the frame-like metallized layer 105, the thickness thereof is thicker. The metal layer 115 brazed to the frame-like metallized layer 105 is used or the frame is directly framed. When the metal lid 113 is joined to the metallized layer 105 via the brazing filler metal 114, the metal lid 113 joined by the thermal stress at the time of joining the metal lid 113 becomes the frame-like metallized layer 105 of the insulating substrate. Even when a thermal stress that pulls toward the center acts, the frame-shaped metallization layer 105 is thickened because the frame-like metallization layer 105 at the outer end to which the stress is applied is thickest. It is possible to realize the wiring board 101a that can firmly restrain the outer peripheral portion thereof by the outer periphery of the frame portion 103. Furthermore, when the outer peripheral surface of the wiring board 101a (the surface located in the dividing groove of the multi-cavity wiring board) is formed by laser processing, the outer peripheral surface is excellent in dimensional accuracy as a product. Thus, it is possible to realize the wiring board 101a in which the occurrence of burrs and chips is suppressed.

A method for manufacturing a multi-piece wiring board according to an embodiment of the present invention will be described. The method for manufacturing a multi-piece wiring board according to the embodiment includes the following steps. That is, a step of preparing a ceramic green sheet having an upper surface and in which a plurality of wiring board regions 101 are arranged. A step of applying a metallizing paste in a frame shape along the boundary 116 of the wiring board region 101 on the upper surface of the ceramic green sheet (which becomes the frame portion 103). And a step of forming the dividing grooves 110 along the respective boundaries 116 of the plurality of wiring board regions 101. Further, in the step of applying the metallizing paste, the metallizing paste is bitten into the laminated body at the boundary 116.

  The ceramic green sheet to which the metallizing paste is applied may be a single layer or a laminate of a plurality of layers. 7 (a) to 7 (c) and FIGS. 8 (a) and 8 (b) show the main parts in the process order of the method for manufacturing a multi-cavity wiring board of the present invention. FIGS. 7A to 7C and FIGS. 8A and 8B are cross-sectional views showing the main parts in the manufacturing method of the multi-cavity wiring board according to the embodiment of the present invention in the order of steps. 7 and 8, the same reference numerals are given to the same parts as those in FIG. 1. In FIGS. 7 and 8 and the following description, reference numerals similar to those used in the description of the multi-cavity wiring board of the embodiment are used without providing separate reference numerals for the ceramic green sheet and the metallizing paste. .

FIG. 7A shows a step of preparing a ceramic green sheet (which becomes the frame portion 103);
On the upper surface, a part of the process of applying the metallizing paste in a frame shape along the boundary 116 of the wiring board region 101 (first auxiliary process) is shown. The ceramic green sheet and the metallizing paste can be manufactured and applied by the same method using the same materials as those described in the description of the multi-cavity wiring board of the embodiment. The metallizing paste to be applied becomes the lower layer 106. The width of the coating pattern in this case is set to a relatively narrow width (first width) as in the lower layer 106.

FIG. 7B shows a part of the step of applying the metallizing paste in a frame shape along the boundary 116 of the wiring board region 101 (second auxiliary step). The metallizing paste to be applied is the upper layer 107. This metallizing paste can also be produced and applied by the same method using the same material as the example given in the description of the multi-cavity wiring board of the embodiment. The width of the coating pattern in this case is set to a relatively wide width (second width) in the same manner as the upper layer 107 covering the lower layer 106.

FIG. 7C shows a process in which the metallizing paste (which becomes the lower layer 106) is bitten into the laminated body which becomes the frame portion 103 at the boundary 116. This step is also performed, for example, by pressing the metallizing paste as described above.

FIG. 8A shows a process of laminating the ceramic green sheet that becomes the base 102 under the ceramic green sheet that becomes the frame 103. The ceramic green sheet used as the base 102 can also be manufactured by the same method using the same material as the example given in the description of the multi-cavity wiring board of the embodiment.

FIG. 8B shows a process of forming the dividing groove 110. The dividing groove 110 can be performed by, for example, laser processing similar to the above. With the formation of the dividing groove 110, the applied metallizing paste (which becomes the lower layer 106 and the upper layer 107) is divided into two in the length direction along the boundary 116 of the wiring board region 101.

  With this manufacturing method, it is possible to easily produce a multi-piece wiring board in a form in which the lower layer 106 serving as the outer end portion of the frame-like metallized layer 105 is cut into the outer periphery of the frame portion 103.

In other words, by making the thickness of the region (boundary 116) that becomes the outer end portion of the metallizing paste that becomes the frame-shaped metallized layer 105 before the dividing grooves 110 are formed, the frame-shaped metallization is increased in the pressing direction. Layer 105 (metallizing paste) bites into the ceramic green sheet. The shape of this bite is rounded. Therefore, the metallizing paste that becomes the lower layer 106 can be easily bitten by pressing on the boundary 116. Further, even if the wiring board region 101 becomes smaller and the width of the frame portion 103 becomes narrower, the metallization paste that becomes the lower layer 106 is applied to the adjacent wiring board region 101 in a wide state where the two frame portions 103 are apparently in contact with each other. It can be formed simultaneously on the outer end. The press of the metallizing paste to the ceramic green sheet may be performed before the step of punching out the frame portion 103 for forming the mounting portion 104. Thereby, the deformation | transformation of the ceramic green sheet by pressurization of the metallizing paste is suppressed.

When the dividing groove 110 is formed along the boundary 116, the lower layer 106 is formed by biting into the outer end portion of the frame portion 103 of the wiring board region 101. Therefore, the frame-like metallized layer 105 and the frame portion 103 are formed. It is possible to provide a manufacturing method capable of efficiently manufacturing the wiring substrate 101a that can increase the bonding area between the frame-like metallized layer 105 and the frame portion 103 by increasing the bonding area.

Note that the multi-cavity wiring board, the wiring board, and the manufacturing method of the multi-cavity wiring board of the present invention are not limited to the examples of the embodiments described above, and various methods are possible without departing from the gist of the present invention. You can make any changes. For example, in the above embodiment, a flat metal lid 113 is joined to the frame-shaped metallization layer 105 via the brazed metal frame 115 or directly to the frame-like metallization layer 105 via the brazing material 114. Although the wiring board 101a is shown, a flat board-like wiring board 101a to which a cap-like metal lid (not shown) is joined instead of the metal lid 113 may be used. Moreover, although the wiring board 101a comprised from the ceramic green sheet of 2 layers was shown, it is good also as the wiring board 101a comprised from the ceramic green sheet of 3 layers or more.

Further, when the frame-shaped metallized layer 105 is composed of the lower layer 106 and the upper layer 107, for example, as shown in FIG. 9, the lower layer 106 is wide enough to cover almost the entire upper surface of the frame portion 103. Yes, the width of the upper layer 107 may be smaller than the width of the lower layer 106. FIG. 9 is an enlarged cross-sectional view showing a main part in another modification of FIG. 9, parts similar to those in FIG. 3 are given the same reference numerals. In the example of FIG. 9, the lower layer 106 is bent downward at the boundary portion (outer end portion) of the wiring board region 101 and bites into the mother board 100. The upper layer 107 is provided on the lower layer 106 at the outer end portion where the lower layer 106 bites into the mother substrate 100. Also in this case, peeling at the outer end portion of the frame-like metallized layer 105 can be effectively suppressed by an anchor effect or the like. However, when a relatively large amount of ceramic particles are contained in the lower layer 106 as described above, when the plating layer 112 is deposited on the frame-like metallized layer 105, as shown in the example of FIG. 3 or FIG. A form in which the upper layer 107 covers the lower layer 106 is preferable.

100 ... Mother board
101 ・ ・ ・ Wiring board area
101a ... Wiring board
102 ... Base
103 ・ ・ ・ Frame part
104 ・ ・ ・ Mounting part
105 ... Frame metallization layer
106 ... Lower layer
107 ... upper layer
108 ・ ・ ・ Wiring conductor
109 ・ ・ ・ Castellation
110 ・ ・ ・ Dividing groove
111 ・ ・ ・ External connection conductor
112 ・ ・ ・ Plating layer
113 ・ ・ ・ Metal lid
114 ... brazing material
115 ・ ・ ・ Metal frame
116 ... Boundary
117 ... Positioning pattern

Claims (10)

A plurality of wiring board regions are arranged, and a mother board having a main surface including a dividing groove provided along the outer periphery of the wiring board region;
A frame-like metallization layer provided along the dividing grooves on the main surface of the mother substrate;
The frame-shaped metallized layer has an outer end portion in contact with the dividing groove that has bitten into the mother substrate, and a region that has bitten into the mother substrate has a thickness that is closer to the dividing groove. Multi-cavity wiring board. The said frame-shaped metallization layer is characterized by including the lower layer located in the said mother board | substrate in the said outer end part, and the upper layer provided on this lower layer. Multi-cavity wiring board. The multi-piece wiring board according to claim 2, wherein the frame-shaped metallized layer contains ceramic particles in at least the lower layer at the outer end portion. The frame-shaped metallized layer contains ceramic particles in the lower layer and the upper layer at the outer end, and the content of the ceramic particles in the lower layer is the content of the ceramic particles in the upper layer. The multi-cavity wiring board according to claim 3, wherein the number of the wiring boards is larger. 5. The multi-cavity wiring board according to claim 2, wherein the lower layer is thicker as it is closer to the outer end portion of the frame-shaped metallized layer. The multi-piece wiring board according to claim 1, wherein the division grooves are formed by laser processing. It further comprises a plating layer provided on the exposed surface of the frame-shaped metallized layer, the dividing groove is formed by laser processing, and the thickness of the plating layer is the lower layer of the frame-shaped metallized layer The multi-piece wiring board according to claim 3, wherein the multi-cavity wiring board is thinner than the upper layer. 8. The wiring board according to claim 1, wherein the multi-cavity wiring board according to claim 1 is divided for each wiring board region. Preparing a ceramic green sheet having an upper surface and a plurality of wiring board regions arranged;
Applying a metallizing paste in a frame shape along the boundaries of the plurality of wiring board regions on the upper surface of the ceramic green sheet;
Forming a dividing groove along each of the boundaries of the plurality of wiring board regions,
In the step of applying the metallization paste, the metallization paste is bitten into the ceramic green sheet at the boundary. The step of applying the metallization paste includes a first auxiliary step of printing the metallization paste with a first width along the boundary of the wiring board region, and the metallization paste more than the first width. 10. The second auxiliary process of claim 9, further comprising a second auxiliary process of printing so as to cover the surface of the ceramic green sheet from the metallizing paste printed in the first auxiliary process with a wide second width. A manufacturing method of a single-piece wiring board.

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