JP3488826B2 - Multi-cavity board for wiring board - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board region for mounting electronic components such as semiconductor elements and quartz oscillators, which is provided on a large-sized mother board in a matrix. The present invention relates to a multi-cavity substrate for a wiring board, which is individually formed. 2. Description of the Related Art Conventionally, a wiring board for mounting electronic components such as a semiconductor element and a quartz oscillator has been used as a substantially flat insulating base made of an electrically insulating material such as an aluminum oxide sintered body. A wiring conductor made of a metal powder of a refractory metal such as tungsten or molybdenum to which the electrodes of the electronic component are connected is attached from the center to the lower surface of the upper surface of the substrate, and a concave portion for housing the electronic component is formed on the upper surface of the insulating base. An insulating frame having an opening for forming is formed by lamination,
An electronic component is accommodated in a concave portion formed by the insulating base and the insulating frame, and electrodes of the electronic component are electrically connected to wiring conductors through electrical connecting means such as a bonding wire or solder. Thereafter, a flat lid is joined to the upper surface of the insulating frame so as to cover the recess, and the electronic components in the recess are hermetically sealed, thereby providing an electronic device as a product. Incidentally, such a wiring board has recently become extremely small in size of about several mm square in accordance with the recent demand for miniaturization of electronic devices. In order to facilitate the production of the wiring board and the electronic device efficiently, a large number of wiring boards are simultaneously and intensively obtained from a single large-area mother board. It is manufactured in the form of an individual substrate. The multi-cavity substrate for a wiring board has a large-area lower insulating layer for forming an insulating base of the wiring board and a large-area upper insulating layer for forming an insulating frame of the wiring board. Thus, a mother board is formed, and a large number of wiring board regions to be a wiring board are vertically and horizontally arranged at the center of the mother board. Wiring conductors are formed in a predetermined pattern from the upper surface to the lower surface of the lower insulating layer in each wiring board region, and electronic components are formed between the lower insulating layer and the upper insulating layer in each wiring board region. An opening forming a recess for accommodating is formed. [0005] The multi-piece substrate for a wiring board has an electronic component in each wiring board area so that the electronic component has a predetermined positional relationship with respect to a wiring conductor attached to the upper surface of the lower insulating layer of each wiring board area. The electrodes of the electronic components housed in the recesses of the respective wiring board regions and the wiring conductors attached to the upper surface of the lower insulating layer of the respective wiring board regions are accommodated in the recesses while being aligned and housed in the recesses. After that, a lid made of, for example, a metal is sealed on the upper surface of the upper insulating layer of each wiring board region, and a predetermined sealing is formed around each opening of the upper insulating layer. A large number of electronic devices are manufactured simultaneously and intensively by aligning and joining them so as to have a width, and finally dividing the mother board into each wiring board area. Here, in order to align electronic components in the recesses of the respective wiring board regions and to position the lid on the upper surface of the upper insulating layer in the respective wiring board regions in the multi-cavity substrate for a wiring board, For example, while providing a waste margin area on the outer peripheral portion of the motherboard, tungsten, molybdenum, or the like having a fixed positional relationship with the opening of each wiring board area of the upper insulation layer is provided on the upper surface of the upper insulating layer in the waste margin area. Alignment marks made of high-melting metal powder metallization are applied by printing, and the positions of the recesses in each wiring board area are calculated based on the alignment marks. And the method of aligning the lid and the opening. [0007] Such a multi-cavity substrate for a wiring board is manufactured by a conventionally well-known ceramic green sheet laminating method. Specifically, first, a ceramic green sheet to be a lower insulating layer and a ceramic green sheet to be an upper insulating layer are prepared. Next, a through hole serving as a lead-out path for a wiring conductor is formed in a region serving as a wiring substrate region of the ceramic green sheet serving as a lower insulating layer, and a wiring substrate region of the ceramic green sheet serving as an upper insulating layer is provided. An opening for forming a concave portion is punched in a region to be formed. Next, a metal paste serving as a wiring conductor is printed on the upper and lower surfaces of the ceramic green sheet serving as the lower insulating layer and the inside of the through hole by a conventionally known screen printing method, and the outer peripheral portion of the ceramic green sheet serving as the upper insulating layer is provided. A metal paste serving as an alignment mark is printed and applied on the upper surface of the area serving as a disposal allowance area by a conventionally well-known screen printing method so as to have a fixed positional relationship with an opening for forming a concave portion of each wiring board area. . Finally, a ceramic green sheet serving as an upper insulating layer is laminated on an upper surface of the ceramic green sheet serving as a lower insulating layer to form a ceramic green sheet laminate. It is manufactured by firing at high temperature. However, according to the conventional multi-cavity substrate for a wiring board, the positioning mark has an upper insulating layer different from the lower insulating layer on which the wiring conductor is attached. Since it is formed by screen printing on the upper surface of the layer, the position due to printing misalignment between the wiring conductor and the lamination misalignment between the lower insulating layer and the upper insulating layer between the lower conductor and the wiring conductor adhered to the upper surface of the lower insulating layer Variations in the relationship occur. In addition, a positional deviation due to printing deviation occurs in each opening of the upper insulating layer. The variation in the positional relationship is 200 to 500
μm, so in recent recent multi-cavity circuit boards for miniaturized and high-density wiring boards, the electronic components are placed in each wiring board area with reference to the alignment mark attached on the upper surface of the upper insulating layer. If it is positioned in the recess, the position of the electrode of the electronic component and the wiring conductor of the lower insulating layer will shift,
As a result, there has been a problem that the electrodes of the electronic component and the wiring conductor cannot be electrically accurately connected.
When the lid is positioned on the upper surface of the upper insulating layer of each wiring board region with reference to the alignment mark attached to the upper insulating layer, the positional relationship between the lid and each opening of the upper insulating layer is shifted. As a result, a predetermined sealing width cannot be provided around each opening of the upper insulating layer, and there is a problem that the airtight reliability of the obtained electronic device is low. The present invention has been devised in view of such a conventional problem, and has as its object to accurately align an electronic component with a wiring conductor attached to a lower insulating layer. The electrodes of the electronic components can be electrically connected accurately to the wiring board, and the lid can be accurately positioned with respect to the opening in the upper insulating layer, making it possible to manufacture highly reliable electronic devices. It is an object of the present invention to provide a multi-cavity substrate for a wiring board. According to the present invention, there is provided a multi-piece board for a wiring board, wherein a plurality of wiring board areas on which wiring conductors to which electrodes of electronic components are connected are attached at a central portion of an upper surface. A lower insulating layer in which alignment marks having a certain positional relationship with the wiring conductors are arranged on the outer peripheral portion of the upper surface, and which are stacked on the upper surface of the lower insulating layer, correspond to the respective wiring board regions. A first opening for forming a recess for accommodating the electronic component, and an upper insulating layer having a second opening having the same shape as the first opening for exposing the alignment mark. Things. According to the multi-cavity substrate for a wiring board of the present invention, the lower insulating board in which a large number of wiring board regions on which wiring conductors to which electrodes of electronic parts are connected are attached is arranged vertically and horizontally at the center of the upper surface. Since alignment marks having a fixed positional relationship with the wiring conductors are arranged on the extension of the center line of the arrangement of the wiring board regions on the outer peripheral portion of the upper surface of the layer, each wiring board region of the lower insulating layer is covered. The variation in the mutual positional relationship between the attached wiring conductor and the alignment mark attached to the outer peripheral portion of the upper surface of the lower insulating layer is extremely small. Since the upper insulating layer has a second opening for exposing the alignment mark, each wiring board of the lower insulating layer is based on the alignment mark exposed from the second opening. The wiring conductor and the electronic component attached to the region can be positioned with extremely high precision. Further, according to the multi-cavity substrate for a wiring board of the present invention, since both the first opening and the second opening are formed in the upper insulating layer, the positional relationship between them is extremely small. It can be small. Then, by using the second opening as a reference when aligning the lid with the first opening of the upper insulating layer, the lid can be extremely accurately positioned with respect to the first opening. . DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a multi-piece substrate for a wiring board according to the present invention will be described in detail with reference to the accompanying drawings. First, an electronic device manufactured by using the multi-piece substrate for a wiring board of the present invention will be described. FIG. 4 is a sectional view showing an example of an electronic device manufactured using a wiring board obtained from the multi-piece wiring board for a wiring board according to the present invention. In FIG. 4, reference numeral 1 denotes an insulating base, 2 denotes an insulating frame, and these constitute a wiring board 3 on which electronic components 4 are mounted. The insulating base 1 is made of an electrically insulating material such as a sintered body of aluminum oxide, a sintered body of aluminum nitride, a sintered body of mullite, a sintered body of silicon nitride, a sintered body of silicon carbide, and a glass ceramic. And a wiring conductor 5 to which the electrode of the electronic component 4 is connected is attached from the center of the upper surface to the lower surface. The wiring conductor 5 is made of, for example, tungsten, molybdenum / molybdenum-manganese, or copper / silver / silver-
An electrode of the electronic component 4 is electrically connected to a central portion of the upper surface of the insulating base 1 through, for example, a bonding wire 6. An insulating frame 2 is laminated on the upper surface of the insulating substrate 1 so as to expose the wiring conductor 5 attached to the center of the upper surface of the insulating substrate 1. The insulating frame 2 is made of, for example, an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, a silicon nitride sintered body, a silicon carbide sintered body, or a glass ceramic sintered body. A substantially rectangular frame made of an electrically insulating material such as that described above, has an opening 2a at the center thereof, and a recess for housing the electronic component 4 on the inner wall surface of the opening 2a and the upper surface of the insulating base 1. 3a is formed. The wiring board 3 accommodates the electronic component 4 in a recess formed by the insulating base 1 and the insulating frame 2, and bonds the electrodes of the electronic component 4 to the wiring conductors 5 of the insulating base 1. It is electrically connected via wires 6, and thereafter, a lid 7 made of a metal such as an iron-nickel-cobalt alloy is joined to the upper surface of the insulating frame 2 so as to cover the opening 2a. An electronic device as a product is obtained by hermetically sealing the electronic component 4 inside a container including the insulating frame 2 and the lid 7. Next, a multi-cavity substrate for a wiring board of the present invention for manufacturing the above-described wiring board 3 will be described. FIG. 1 is a sectional view showing an example of an embodiment of a multi-piece board for a wiring board according to the present invention, and FIG. 2 is a top view of the multi-piece board for a wiring board shown in FIG. As shown in FIGS. 1 and 2, the multi-piece substrate for a wiring board according to the present invention comprises a lower insulating layer 11 for forming the insulating base 1 of the wiring board 3, and an insulating frame of the wiring board 3. 2
Is formed of a substantially rectangular flat mother board 10 having a large area of several cm to several tens cm in length and width, and a wiring board 3 serving as a wiring board 3 in the center thereof. Region 13
Are arranged vertically and horizontally, and a frame-shaped throwaway area 14 is formed in the outer peripheral portion of the mother board 10 to facilitate handling of the multi-piece wiring board. The mother substrate 10 includes a lower insulating layer 11 and an upper insulating layer 12.
Are made of an electrically insulating material such as an aluminum oxide-based sintered body, an aluminum nitride-based sintered body, a mullite-based sintered body, a silicon nitride-based sintered body, a silicon carbide-based sintered body, or a glass ceramic, and the lower insulating layer 11 It is manufactured by laminating and firing a ceramic green sheet to be an upper insulating layer 12 and a ceramic green sheet to be an upper insulating layer 12. The lower insulating layer 11 constituting the mother substrate 10 is formed of a metal powder of metal such as tungsten or molybdenum / molybdenum-manganese / copper / silver / silver / palladium from the center of the upper surface to the lower surface of each wiring substrate region 13. The wiring conductor 5 is attached. The wiring conductor 5 has a through hole that is a lead-out path for the wiring conductor 5 formed in the ceramic green sheet that is to be the lower insulating layer 11 and extends from the upper surface of the ceramic green sheet to the lower surface through the through hole. The metal paste 5 is formed by printing and applying a predetermined pattern using a conventionally known screen printing method. Further, the lower insulating layer 11 has a waste margin region 14.
Is positioned on the upper surface of the lower insulating layer 11, a positioning mark 15 having a fixed positional relationship with the wiring conductor 5 provided on the upper surface of each wiring substrate region 13. The alignment mark 15 is, for example, a cross in which two linear patterns extending in a direction coinciding with the direction of the arrangement of the wiring board regions 13 are cross-shaped. The alignment mark 15 is arranged so that the center line of one of the patterns of the alignment mark 15 coincides with the extension of the center line. The alignment mark 15 is made of tungsten, molybdenum, molybdenum-manganese,
It is made of metal powder such as copper, silver, silver-palladium and the like, and a metal paste to be the wiring conductor 5 is printed and applied to the upper surface of the ceramic green sheet to be the lower insulating layer 11 in a predetermined pattern at the same time. Formed by The alignment marks 15 are formed by printing a metal paste for the alignment marks 15 on the upper surface of the ceramic green sheet for the lower insulating layer 11 at the same time as the metal paste for the wiring conductors 5. The variation in the positional relationship with the wiring conductor 5 attached to the upper surface of the lower insulating layer 11 is extremely small at about 50 μm or less. Therefore, the electronic component 4 is placed on the lower insulating layer with reference to the positioning mark 15.
When the electronic component 4 and the wiring conductor 5 are aligned with the wiring conductor 5 attached to the upper surface of each wiring substrate region 13 of the electronic component 11, the electronic component 4 and the wiring conductor 5 can be aligned with extremely high precision. It is possible to electrically and accurately connect the wiring conductor 5 attached to the upper surface of each wiring substrate region 13 of the lower insulating layer 11. The upper insulating layer 12 constituting the mother substrate 10 is
A first opening 12a for forming a recess 3a for accommodating the electronic component 4 is formed in each wiring board region 13 corresponding to the wiring board region 13 of the lower insulating layer 11. First opening 12a formed in upper insulating layer 12
Forms a recess 3 a for accommodating the electronic component 4 with the lower insulating layer 11, and exposes the wiring conductor 5 attached to the center of the upper surface of each wiring board region 13 of the lower insulating layer 11. ing. The electronic component 4 is accommodated in the recess 3 a of each wiring board region 13, and the electrodes of the electronic component 4 are connected to the wiring conductors 5 of each wiring board region 13 through the bonding wires 6, whereby the electronic components are connected. 4 and the wiring conductor 5 in each wiring board area 13 are electrically connected to each other, and the upper insulating layer
The electronic component 4 is hermetically accommodated in the concave portion 3a by joining the lid 7 so as to cover each concave portion 3a around each opening 12a on the upper surface of the 12. Further, in the disposal area 14 of the upper insulating layer 12,
A certain positional relationship with the first opening 12a, and a lower insulating layer
Positioning mark formed on the top surface of the discarding allowance area 14 of 11
For example, a second opening 12b having a substantially square shape is formed to expose the second opening 15b. The second opening 12b formed in the throw-away area 14 of the upper insulating layer 12 is used for exposing the alignment mark 15 formed on the upper surface of the throw-away area 14 of the lower insulating layer 11 so that the alignment mark 15 is formed. The mark 15 can be recognized from outside. Also, by having a fixed positional relationship with the first opening 12 a, the lid 7 can be placed in the first insulating substrate 12 in the first insulating substrate 12.
When the lid 7 is joined to the upper surface around the opening 12a of the
Functions as a reference when aligning with 12a. The first opening formed in the upper insulating layer 12
The second opening 12b and the second opening 12b are simultaneously formed by subjecting a ceramic green sheet serving as the upper insulating layer 12 to a conventionally known punching process. Since the first opening 12a and the second opening 12b formed in the upper insulating layer 12 are formed at the same time by punching in the same layer, the variation in the positional relationship between them is about 50 μm. The following is extremely small. Therefore, the second
By using the opening 12b as a reference, the lid 7 can be accurately positioned with respect to the first opening 12a. Next, a method of manufacturing an electronic device using the multi-piece substrate for a wiring board of the present invention will be described. First, the alignment mark 15 exposed in the second opening 12b of the upper insulating layer 12 is recognized by the image recognition device, and the position of the alignment mark 15 is detected. Then, the position of the wiring conductor 5 attached to the upper surface of the lower insulating layer 11 of each wiring board region 13 is calculated based on the detected position of the alignment mark 15. Then, based on the calculated position data of the wiring conductor 5, the electronic component 4 is moved by the automatic machine to a predetermined positional relationship with the wiring conductor 5 attached to the upper surface of the lower insulating layer 11 of each wiring board region 13. The electrodes of these electronic components 4 and the wiring conductors 5 attached to the upper surface of the lower insulating layer 11 of each of the wiring board regions 13 are accommodated in the concave portions 3a of each of the wiring board regions 13 so that Are electrically connected via bonding wires 6. In this case, since the positioning mark 15 is formed on the upper surface of the lower insulating layer 11 at the same time as the wiring conductor 5, the position between the positioning mark 15 and the wiring conductor 5 on the upper surface of the lower insulating layer 11 is reduced. Variations in the positional relationship are extremely small. Therefore, the electronic component 4 is mounted on the wiring conductor 5 attached on the lower insulating layer 11 of each wiring board region 13 with reference to the alignment mark 15.
Can be accurately aligned, and as a result, the electrodes of the electronic component 4 and the wiring conductors 5 can be electrically and accurately connected. Next, the image recognition device recognizes the second opening 12b formed in the upper insulating layer 12 and detects the position of the second opening 12b. Then, based on the detected position of the second opening 12b, the position of the first opening 12a formed in the upper insulating layer 12 of each wiring board region 13 is calculated.
Then, based on the calculated position data of the first opening 12a, the first opening 12a is formed on the upper surface of the upper insulating layer 12 of each wiring board region 13.
The lid 7 is positioned and joined by an automatic machine so as to have a predetermined sealing width around a. In this case, the second opening 12b is
Since the upper insulating layer 12 is stamped and formed at the same time as the first opening 12a, the variation in the positional relationship with the first opening 12a is extremely small. First opening formed in upper insulating layer 12
The lid 7 can be accurately positioned with respect to 12a, and as a result, the electronic component 4 can be hermetically sealed inside the recess 3a of each wiring board region 13. Finally, the mother board 10 is connected to each wiring board area.
If divided into 13 units, a large number of electronic devices can be manufactured simultaneously and intensively. In order to divide the mother board 10 into the respective wiring board areas 13, division grooves having a predetermined depth are formed in advance on the upper and lower surfaces of the mother board 10 along the boundaries of the respective wiring board areas 13. A method of so-called chocolate break of the mother substrate 10 along the dividing groove, or a method of cutting and dividing the mother substrate 10 along a boundary of each wiring substrate region 13 with a laser or a diamond cutter is adopted. Thus, according to the multi-piece substrate for wiring board of the present invention, the electronic component 4 is accurately positioned with respect to the wiring conductor 5 attached to the upper surface of the lower insulating layer 11 of each wiring board region 13. The electrode of the electronic component 4 and the wiring conductor 5 of each wiring board region 13 can be electrically and accurately connected to each other, and the first opening 12a formed in the upper insulating layer 12 of each wiring board region 13 On the other hand, the electronic component 4 can be housed with high airtightness in the concave portion 3a of each wiring board region 13 by accurately aligning the lid 7, and the wiring conductor 5 and the electrode of the electronic component 4 can be electrically accurately detected. A large number of electronic devices that are connected and in which the electronic components 4 are sealed with high hermetic reliability can be manufactured simultaneously and collectively. The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. For example, in the example of the above-described embodiment, the alignment mark 15 is
13 are arranged corresponding to the outermost row, but as shown in the top view similar to FIG. 2 in FIG. 3, even if all the rows of the wiring board area 13 are arranged corresponding to each other. Good. Further, the shape of the alignment mark 15 is not limited to the cross shape, but may be another shape such as a circle, a square, or a triangle. As described above, according to the multi-piece substrate for wiring board of the present invention, the outer peripheral portion of the upper surface of the lower insulating layer on which the wiring conductor to which the electrode of the electronic component is connected is attached. Since the alignment mark having a fixed positional relationship with the wiring conductor is arranged on an extension of the center line of the arrangement of the wiring board region, the wiring conductor attached to each wiring board region of the lower insulating layer and Variations in the mutual positional relationship between the lower insulating layer and the positioning mark attached to the outer peripheral portion of the upper surface are extremely small. Therefore, the electronic component and the wiring conductor can be aligned with extremely high accuracy based on the alignment mark.
As a result, it is possible to electrically accurately connect the electrode of the electronic component and the wiring conductor. According to the multi-cavity substrate for a wiring board of the present invention, since the first opening and the second opening are both formed in the upper insulating layer, the positional relationship between the first and second openings is extremely small. small. Therefore, the lid and the first opening can be positioned with high accuracy based on the second opening, and
As a result, the lid can be provided with a predetermined sealing width around each of the first openings on the upper insulating layer on the upper surface of each wiring board region and joined with high airtightness, thereby providing an electronic device with high airtight reliability. be able to. As described above, according to the present invention, the electronic component can be accurately positioned with respect to the wiring conductor adhered to the lower insulating layer, and the electrode of the electronic component and the wiring board can be electrically accurately positioned. And the lid can be accurately positioned with respect to the opening in the upper insulating layer,
A multi-cavity substrate for a wiring board capable of manufacturing an electronic device with high airtight reliability was provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing an example of an embodiment of a multi-piece substrate for a wiring board according to the present invention. FIG. 2 is a top view of the multi-piece circuit board for a wiring board shown in FIG. 1; FIG. 3 is a top view showing another example of the embodiment of the multi-piece substrate for a wiring board of the present invention. FIG. 4 is a cross-sectional view of an electronic device manufactured using the multi-cavity substrate for a wiring board of the present invention. [Description of Symbols] 3a... Recesses 4... Electronic components 5... Wiring conductors 11... Lower insulating layer 12... Upper insulating layer 12a. ... Wiring board area 15 ... Positioning mark

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H05K 1/02 H05K 3/00 H05K 3/46 H01L 21/60 H01L 23/12 H01C 17/06

Claims (1)

(1) A plurality of wiring board regions on which wiring conductors to which electrodes of an electronic component are connected are arranged vertically and horizontally at the center of the upper surface, and are fixed to the wiring conductors. A lower insulating layer in which an alignment mark having the following positional relationship is disposed on an extension of the center line of the arrangement of the wiring substrate regions on the outer peripheral portion of the upper surface, and the respective wiring boards laminated on the upper surface of the lower insulating layer wherein exposing the first opening and the mark for the alignment to form a recess for accommodating the electronic component corresponds to a region first
And an upper insulating layer having a second opening of the same shape .