JP2003318314A - Multi-cavity circuit substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-cavity circuit substrate which can deposit a plating metal layer on an independent metallized wiring conductor of each wiring substrate region arranged on a ceramic base substrate by an electrolytic plating method. <P>SOLUTION: The multi-cavity circuit substrate comprises wiring substrate regions 2 each having a recess 2a for housing an electronic component and arranged to be formed laterally and longitudinally at the central part of the ceramic base substrate 1 on an upper surface, and non-connected independent metallized wiring conductors 6c, 6d deposited and formed on a sealing metallized layer 7 in each region 2 from the layer 7 and the recess 2a of the region 2 electrically connected to each other on the upper surface of the region 2 to the outer periphery. In this substrate, the conductors 6c, 6d are electrically connected to the layer 7 of the region 2 via connecting conductors 11a, 11b. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small-sized wiring for accommodating electronic components in a central portion of a ceramic mother substrate formed by laminating a plurality of insulating layers. The present invention relates to a multi-cavity wiring board in which a large number of substantially rectangular wiring board regions serving as substrates are formed vertically and horizontally and integrally arranged. 2. Description of the Related Art Conventionally, a small-sized wiring board used for an electronic component housing package for housing an electronic component such as a semiconductor element or a quartz oscillator is made of, for example, a ceramic such as an aluminum oxide sintered body. Consisting of a plurality of insulating layers consisting of a plurality of layers and having a concave portion for accommodating an electronic component on the upper surface, and a substantially square-shaped insulating substrate. A plurality of metallized wiring conductors, and a frame-shaped metallizing layer for sealing, which is attached to the upper surface of the insulating base so as to surround the recess. Some of the metallized wiring conductors are electrically connected to the encapsulation metallization layer, and others are electrically independent of the encapsulation metallization layer. The metallized wiring conductor connected to the metallizing layer for sealing is usually a metallized wiring conductor for grounding, and the metallized wiring conductor electrically independent from the metallizing layer for sealing is a metallized wiring conductor for signals. According to this wiring board, the electronic component is accommodated in the concave portion of the insulating base, and the electrode of the electronic component is electrically connected to the metallized wiring conductor on the bottom surface of the concave portion via a conductive adhesive or a bonding wire. After connecting and then
An electronic device as a product is obtained by joining a metal lid to the sealing metallization layer on the upper surface of the insulating substrate so as to cover the concave portion and hermetically housing the electronic component in the concave portion. The metallized wiring layer derived from the outer periphery to the lower surface is connected to the wiring conductor of the external electric circuit board via solder, so that the electrodes of the electronic components mounted on the external electric circuit board and accommodated are electrically connected to the external electric circuit. Will be connected. [0004] In recent years, with the recent demand for miniaturization of electronic devices, the size of such a wiring board has become extremely small, about several mm square, and a large number of wiring boards must be handled. In order to facilitate the manufacture of the wiring board and the electronic device, and to efficiently manufacture the wiring board and the electronic device, a large number of wiring boards are simultaneously and intensively obtained from one large-area ceramic mother board. It is manufactured in the form of an individual wiring board. This multi-cavity wiring board has a concave portion for accommodating an electronic component on an upper surface thereof in a central portion of a substantially flat ceramic mother substrate formed by laminating a plurality of insulating layers. A large number of substantially rectangular wiring board regions in which a plurality of metallized wiring conductors extending from the bottom surface of the concave portion to the bottom surface through the outer periphery to the bottom surface and a frame-shaped encapsulating metallization layer on the upper surface surrounding the concave portion are integrated vertically and horizontally. The metallized wiring conductor for grounding and the metallization layer for sealing in each wiring board area are electrically connected to each other in the wiring board area. Then, before or after accommodating the electronic component in the recess of each wiring board area, a large number of wiring boards or electronic devices are simultaneously and intensively manufactured by dividing the ceramic mother board into each wiring board area. . In such a multi-cavity wiring board, the metallized wiring conductors and the metallization layer for sealing are prevented from being oxidized and corroded, and the metallized wiring conductors and the electrodes of the electronic components and the wiring of the external electric circuit board are prevented. In order to improve the electrical connection with the conductor and the bonding between the metallizing layer for sealing and the metal cover, the exposed surface of each metallized wiring conductor and the metallizing layer for sealing has a thickness of 1 to 1 for example.
Nickel plating layer of about 0 μm and thickness of 0.1 to 3 μm
Gold plating layers are sequentially applied by electrolytic plating. Heretofore, in such a multi-cavity wiring board, a ceramic mother board is required to apply a nickel plating layer or a gold plating layer to each metallized wiring conductor or metallizing layer for encapsulation by electrolytic plating. Between the insulating layers,
All metallized wiring conductors are electrically connected by providing a plurality of connection conductors for plating conduction that electrically connect adjacent metallized wiring conductors in each wiring board area to each other across the boundary of each wiring board area. A method has been adopted in which a common connection is made, and an electric charge for electrolytic plating is supplied through the connection conductor to perform electrolytic plating on the exposed surfaces of each metallized wiring conductor and the metallized layer for sealing. Since the metallized wiring conductors adjacent to each wiring board region are electrically connected to each other by the plating conductive connection conductors across the boundary of each wiring board region, the ceramic mother board is connected to each wiring board wiring. After being divided into substrate regions, each will be electrically independent of the other. [0009] However, recent wiring boards have been miniaturized and densified.
The distance between adjacent metallized wiring conductors has become extremely narrow. Also, in a multi-cavity wiring board for obtaining such a wiring board, a plurality of metallized wiring conductors adjacent to each other are electrically connected to each other across the boundary of each wiring board region, and a plurality of connection conductors for plating conduction are provided. Has become extremely difficult. Therefore, it has become difficult to electrically connect the metallized wiring conductors in common with such connection conductors and to apply a plating metal layer to each metallized wiring conductor or the metallization layer for sealing by electrolytic plating. . The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to connect adjacent metallized wiring conductors in each wiring board area arranged on a ceramic mother board to each wiring board area. It is possible to apply a plating metal layer to each metallized wiring conductor and encapsulation metallized layer by an electrolytic plating method without providing a plating conductive connection conductor that electrically connects with each other across the boundary line of An object of the present invention is to provide a multi-cavity wiring board. According to the present invention, there is provided a multi-piece wiring board for accommodating electronic components on a top surface of a ceramic mother board formed by laminating a plurality of insulating layers. A large number of substantially rectangular wiring board regions having recesses are formed vertically and horizontally in an array, and a frame-shaped sealing metallization layer electrically connected to the upper surface of each of the wiring board regions and surrounding the recesses respectively. A multi-cavity wiring board formed by applying a non-connected independent metallized wiring conductor to the sealing metallization layer in each of the wiring board areas from the inside of the recess to the outer periphery of the wiring board area, The independent metallized wiring conductor is provided on the sealing metallization layer in a wiring board area adjacent to a wiring board area on which the independent metallized wiring conductor is formed. The inside of the substrate is electrically connected by a connection conductor extending from the independent metallized wiring conductor to the metallization layer for sealing in the adjacent wiring substrate region. According to the multi-cavity wiring board of the present invention, the metallization layers for sealing in the respective wiring board regions are electrically connected to each other, and the metallization layers in the respective wiring board regions are not connected to the metallization layers for sealing. The inside of the ceramic motherboard is separated from the independent metallized wiring conductor by the metallization layer for sealing in the wiring board area adjacent to the wiring board area on which the independent metallized wiring conductor is formed. Since the connection is made electrically by the connection conductor extending to the metallization layer for encapsulation of the region, the charge for electrolytic plating is supplied to the independent metallized wiring conductor from the metallization layer for encapsulation of the adjacent wiring board region, and the electrolytic plating is performed. Can be performed, so that a boundary line of each wiring board area is formed between adjacent metallized wiring conductors in each wiring board area. Sectional and without providing a connection conductor for electrically connecting therebetween, it is possible to deposit a plated metal layer by electrolytic plating on all metallized wiring conductor and the sealing metallized layer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A multi-cavity wiring board according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a top view showing an example of an embodiment of a multi-cavity wiring board of the present invention,
FIG. 2 is a cross-sectional view of the multi-piece wiring board shown in FIG. In the figure, reference numeral 1 denotes a ceramic mother board, and 2 denotes a wiring board area. The ceramic mother substrate 1 is formed by laminating two insulating layers 1a and 1b made of a ceramic material such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, and a glass-ceramic. A plurality of substantially rectangular wiring board regions 2 are formed at the center of the plate, and are vertically and horizontally arranged in a line at a center portion of the wiring board region 2 by a boundary line 3. Line 3
A circular through-hole 4 is formed on the intersection of. Further, a frame-shaped waste area 5 is formed in the outer peripheral portion. The ceramic mother substrate 1 is manufactured by a ceramic green sheet laminating method. Specifically, ceramic green sheets for the insulating layers 1a and 1b are prepared, and the ceramic green sheets are formed on the ceramic green sheets. It is manufactured by punching a punched hole or the like for the through hole 4 and then laminating and firing it at a high temperature. Each of the wiring board regions 2 arranged in the center of the ceramic mother substrate 1 is a region that becomes a small wiring board for an electronic device, and accommodates electronic components in the center of the upper surface of each. A plurality of metallized wiring conductors 6 extending from the bottom surface of the concave portion 2a to the lower surface via opposed outer peripheries are formed in the concave portion 2a.
A sealing metallization layer 7 to which a metal lid for hermetically sealing the recess 2a is bonded is formed on the upper surface surrounding the recess 2a. An inner wall metallization (not shown) connecting the sealing metallization layers 7 to each other is formed on the inner wall of the through hole 4 formed on the boundary line 3 separating the wiring board regions 2 over the entire circumference. Have been. The metallized wiring conductor 6, the metallizing layer 7 for sealing, and the metallization on the inner wall are formed from metal powders of metal such as tungsten, molybdenum, copper and silver. The recess 2a of each wiring board region 2 is formed by punching a substantially rectangular through hole for the recess 2a in a ceramic green sheet for the insulating layer 1b. Metallization layer 7 for sealing and inner wall metallization are formed on the upper and lower surfaces or through holes 4 of ceramic green sheets for insulating layers 1a and 1b.
The metallized wiring conductor 6, the metallized layer 7 for sealing, and the metallized paste for metallizing the inner wall are printed and applied in a predetermined pattern on the side surfaces of the punched holes for metallization. Each wiring board region 2 has its recess 2
a, electronic components such as a semiconductor element and a quartz oscillator are accommodated, and each electrode of the electronic component is electrically connected to the metallized wiring conductor 6 in the recess 2a via, for example, a solder bump or a bonding wire. Thereafter, the electronic component is hermetically sealed in the recess 2a by joining a metal lid to the sealing metallization layer 7 on the upper surface of each wiring board region 2 via a brazing material. By dividing the wiring board area 2 along the boundary 3, a large number of electronic devices are obtained. The semiconductor device is mounted on the external electric circuit board and housed therein by connecting the metallized wiring conductor 6 extending from the outer periphery to the lower surface to the wiring conductor of the external electric circuit board via solder. The electronic component will be electrically connected to the external electric circuit. In order to divide the ceramic mother substrate 1 along the boundary 3 between the wiring substrate regions 2, division grooves are formed on the upper and lower surfaces of the ceramic mother substrate 1 on the boundary 3 between the wiring substrate regions 2. A method of bending along the dividing groove or a method of cutting the ceramic mother substrate 1 along a boundary 3 of each wiring board region 2 by a diamond cutter, a laser cutter or the like is adopted. In this multi-cavity wiring board, the surface of each metallized wiring conductor 6 in each wiring board region 2, the metallization layer 7 for sealing, and the inner wall metallized on the inner wall of the through hole 4 are provided. These metallized wiring conductors 6, sealing metallization layer 7 and inner wall metallization are prevented from being oxidized and corroded, and each metallized wiring conductor 6 is connected to an electrode of an electronic component or a wiring conductor of an external electric circuit board and sealed. In order to improve the bonding between the metallizing layer 7 for metal and the metal lid, it is usually 1 to
Nickel plating layer of about 10 μm thickness and 0.1 to 3 μm
A gold plating layer having a thickness of about m is sequentially applied by an electrolytic plating method. The disposal area 5 formed on the outer peripheral portion of the ceramic mother substrate 1 is an area for facilitating the handling of the multi-piece wiring board when manufacturing or transporting the multi-piece wiring board. On the upper surface thereof, there is provided a frame-shaped plating conduction metallization layer 8 electrically connected to the innermost metallization layer of the inner wall metallization applied to the inner wall of each through hole 4. Further, a metallizing terminal 9 for plating conduction electrically connected to the metallizing layer 8 for plating conduction is formed on the outer peripheral side surface thereof. These plating conductive metallization layers 8 and plating conductive metallized terminals 9 are used to supply electric charges for electrolytic plating to each metallized wiring conductor 6, sealing metallized layer 7 and inner wall metallized in each wiring board region 2. It functions as a conductive path, and supplies a charge for electrolytic plating to each inner wall metallization / sealing metallization layer 7 and metallization wiring conductor 6 from the plating metallization terminal 9 via the plating metallization layer 8 to perform electrolysis. By plating, a nickel plating layer and a gold plating layer are sequentially applied to the surfaces of each metallized wiring conductor 6, sealing metallization layer 7, and inner wall metallization. Such a metallization layer 8 for plating conduction and a metallized terminal 9 for plating conduction are
A metallized metal powder of tungsten, molybdenum, copper, silver, etc., is formed from a metallized metallized paste. It is formed by printing and coating on the surface. In the multi-cavity wiring board of the present invention, the metallized wiring conductor 6 in each wiring board area 2 is connected to the wiring board area 2 as shown in FIG.
And a metallized wiring conductor 6a for grounding connected to the metallizing layer 7 for sealing, and independent metallized wiring conductors 6b, 6c, 6d and 6e not connected to the metallizing layer 7 for sealing in the wiring board region 2. I have. The ground metallized wiring conductor 6a in each wiring board region 2 is connected to the sealing metallized layer 7 by a through conductor 10 penetrating through the insulating layer 1b in the wiring board region 2, and this ground metallized wiring is provided. A nickel plating layer and a gold plating layer are applied to the conductor 6a by supplying a charge for electrolytic plating from the sealing metallized layer 7 through the through conductor 10 and performing electrolytic plating. The through conductor 10 is made of tungsten, molybdenum,
It is made of metallized metal powder such as copper, silver, and the like.
And a metallizing paste for the through conductor 10 is filled in the through hole. Further, of the independent metallized wiring conductors 6,
6b is connected to the metallized wiring conductor 6a for grounding in the adjacent wiring board region 2 and the independent metallized wiring conductor 6b is connected to the metallized wiring conductor 6a for grounding in the adjacent wiring board region 2 for electrolytic plating. The nickel plating layer and the gold plating layer are deposited by supplying the electric charges and performing the electrolytic plating. In the independent metallized wiring conductor 6,
6c and 6d are connected to the sealing metallization layer 7 of the adjacent wiring board region 2 via connection conductors 11a and 11b, and these independent metallization wiring conductors 6c and 6d have
A nickel plating layer and a gold plating layer are deposited by supplying a charge for electrolytic plating from the sealing metallization layer 7 of the adjacent wiring board region 2 via the connection conductors 11a and 11b and performing electrolytic plating. . The connection conductor 11
a and 11b are formed from metal powders of metal such as tungsten, molybdenum, copper, silver, etc., and extend from the independent metallization layers 6c and 6d to the adjacent wiring board region 2 between the insulating layers 1a and 1b and the insulating layer. 1b. Then, a through hole for providing a through conductor is formed in the ceramic green sheet for the insulating layer 1b, a metallizing paste for the through conductor is filled in the through hole, and an upper surface of the ceramic green sheet for the insulating layer 1a is formed. Is formed by printing and applying a metallization paste for a horizontal conductor in a predetermined pattern. Further, among the independent metallized wiring conductors,
Reference numeral 6e is connected to the independent metallized wiring conductor 6d of the adjacent wiring board region 2, and the independent metallized wiring conductor 6e is connected to the charge for electrolytic plating via the independent metallized wiring conductor 6d of the adjacent wiring board region 2. The nickel plating layer and the gold plating layer are adhered by supplying and supplying electrolytic plating. As described above, according to the multi-cavity wiring board of the present invention, the connection extending inside the ceramic mother substrate 1 from the independent metallized wiring conductors 6c and 6d to the sealing metallized layer 7 in the adjacent wiring board area 2. Since the conductors 11a and 11b are provided, the metallized wiring conductor 6a for grounding in each wiring board area 2 is connected to the independent metallized wiring conductor 6b from the sealing metallization layer 7 in the wiring board area 2 via the through conductor 10. Are independent metallized wiring conductors 6c, via the metallized wiring conductors 6a for grounding in the adjacent wiring board region 2,
Electrodes 6d are formed from the metallization layer 7 for sealing in the adjacent wiring board region 2 via the connection conductors 11a and 11b, and the independent metallized wiring conductor 6e is formed via the independent metallized wiring conductor 6d in the adjacent wiring board region 2. The nickel plating layer and the gold plating layer can be deposited by supplying an electric charge for plating and performing electrolytic plating.
Accordingly, the metallized wiring conductors 6 adjacent to each other in each wiring board region 2 are electrically connected to each other by electrically connecting the metallized wiring conductors 6 across the boundary 3 of each wiring board region 2. It is not necessary to provide between metallized wiring conductors 6 adjacent to each other.
Even if the distance between the metallized wiring conductors is extremely small, a plated metal layer can be applied to each metallized wiring conductor 6 and the sealing metallized layer 7 by an electrolytic plating method. Also,
The independent metallized wiring conductor 6b is connected to the adjacent wiring board region 2
The independent metallized wiring conductors 6c and 6d are connected to the sealing metallization layer 7 in the adjacent wiring board region 2, and the independent metallized wiring conductor 6e is connected to the independent metallized wiring conductor 6d in the adjacent wiring board region 2. When the ceramic mother substrate 1 is divided into the respective wiring board regions 2 along the boundary line 3, each of the independent metallized wiring conductors 6 in each of the divided wiring board regions 2 is connected.
Each of b, 6c, 6d and 6e becomes an electrically independent metallized wiring conductor 6. Thus, according to the multi-cavity wiring board of the present invention, the electronic component is mounted and fixed in the concave portion 2a of each wiring board region 2, and the electrode of the electronic component and each metallized wiring conductor 6 are electrically connected. After the connection, the metal cover is joined to the sealing metallization layer 7 on the upper surface of each wiring board region 2 via a brazing material, and the ceramic mother substrate 1 is connected to each wiring board region 2 along the boundary line 3. By dividing, a large number of electronic devices are simultaneously and intensively manufactured. The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention. In one example, the ceramic mother substrate 1 is formed by laminating two insulating layers 1a and 1b, but the ceramic mother substrate 1 may be formed by laminating three or more insulating layers. According to the multi-cavity wiring board of the present invention,
While electrically connecting the sealing metallization layers of each wiring board region to each other, an independent metallized wiring conductor not connected to the sealing metallization layer in each wiring board region,
The inside of the ceramic mother board is sealed from the independent metallized wiring conductor to the metallizing layer for sealing the adjacent wiring board region on the sealing metallization layer in the wiring substrate region adjacent to the wiring substrate region on which the independent metallized wiring conductor is formed. Since the electrical connection is made by the connection conductor extending to the layer, the independent metallized wiring conductor can be supplied with the charge for the electrolytic plating from the metallization layer for sealing in the adjacent wiring substrate region, so that the electrolytic plating can be performed. All metallized wiring conductors and sealing are provided between adjacent metallized wiring conductors in each wiring board area without providing a connection conductor that traverses the boundary of each wiring board area and electrically connects the two. A plating metal layer by electrolytic plating can be applied to the metallizing layer for use.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view showing an example of an embodiment of a multi-piece wiring board according to the present invention. FIG. 2 is a cross-sectional view of the multi-piece wiring board shown in FIG. FIG. 3 is a partially enlarged top view of the multi-piece wiring board shown in FIG. 1; [Description of Signs] 1 ... Ceramic mother board 2 ... Wiring board area 2a ... Recess 3 for accommodating electronic components ... Boundary line 6 Metallized wiring conductors 6b, 6c, 6d, 6e Independent metallized wiring conductor 7 Metallizing layers 11a, 11b for sealing Connection conductor

Claims (1)

Claims: 1. A large number of substantially rectangular wiring boards each having a concave portion for accommodating an electronic component in a central portion of a ceramic mother substrate formed by laminating a plurality of insulating layers. The regions are arranged vertically and horizontally, and are electrically connected to the upper surface of each of the wiring substrate regions, and each has a frame-shaped sealing metallization layer that surrounds the concave portion. A multi-cavity wiring board formed by applying a non-connected independent metallized wiring conductor to the sealing metallization layer in each of the wiring board regions, wherein the independent metallized wiring conductor is In the encapsulation metallization layer in the wiring board area adjacent to the wiring board area on which the conductors are formed, the inside of the ceramic motherboard is separated into the independent metallized wiring conductors. Multiple patterning wiring board, characterized in that it is electrically connected by a connection conductor extending to the sealing metallized layer of the wiring substrate region et said adjacent.