JP6185695B2 - Multilayer wiring board and manufacturing method thereof - Google Patents

Description

  In the present invention, for example, in order to inspect the electrical characteristics of electronic components such as a large number of semiconductor elements formed on a Si wafer, an insulating layer made of a resin and an insulating layer made of a ceramic having a higher hardness than the resin are used. In particular, the present invention relates to a multilayer wiring board for electronic component inspection and the like and a manufacturing method thereof, in which two or more types of insulating layers having different hardnesses are laminated.

  A multilayer wiring board for electronic component inspection includes, for example, a ceramic multilayer wiring board including a plurality of ceramic layers, internal electrodes disposed between the ceramic layers, and via conductors penetrating the ceramic layers, and the ceramic multilayer wiring. Two insulations different in hardness from a resin multilayer wiring board including a plurality of resin insulation layers, a conductor layer disposed between the resin insulation layers, and a via conductor penetrating the resin insulation layer above the surface of the substrate A plurality of terminals for attaching a probe are formed on the surface of the resin multilayer wiring board, and the vias exposed on the back surface of the resin multilayer wiring board are formed on the surface of the ceramic multilayer wiring board. A plurality of connection terminals having a thickness of about 15 μm are provided so as to protrude from the end face of the conductor (see, for example, Patent Document 1).

  By the way, the connection terminal is, for example, a Ti thin film layer and a Cu thin film layer formed by sputtering on the surface of the ceramic multilayer wiring substrate, a Cu plating film in which both side surfaces and the upper surface of the latter are sequentially coated by electrolytic metal plating, Ni It has a five-layer structure of a plating film and an Au plating film. Therefore, when the resin multilayer wiring board, which is softer than the ceramic multilayer wiring board, is laminated above the surface of the ceramic multilayer wiring board, and further crimped while being heated, the peripheral portion on the top surface of the connection terminal ( The edge) bites into the resin insulating layer located on the back side of the resin multilayer wiring board with a shearing force, so that the insulating layer may be cracked or broken. If the crack or the like occurs inside the resin insulation layer, it causes a problem such as deterioration of insulation performance or short circuit due to an inadvertent conduction path, resulting in deterioration of inspection performance or electrical characteristics. was there.

JP 2009-76873 A (pages 1 to 20, FIG. 3)

  The present invention solves the problems described in the background art, and is formed by laminating two or more insulating layers having different hardnesses, and the insulating layer on the side having a low hardness adjacent to the plurality of insulating layers. It is an object of the present invention to reliably provide a multilayer wiring board in which cracks are unlikely to occur and a manufacturing method thereof.

Means for Solving the Problems and Effects of the Invention

In order to solve the above-mentioned problems, the present invention sets the thickness of the connection terminal that protrudes from the surface of the insulating layer with high hardness and contacts the end surface of the through conductor exposed on the back surface of the insulating layer with low hardness to 2 μm or less. It was designed with the idea in mind.
That is, the multilayer wiring board of the present invention (Claim 1) includes a first insulating layer made of an insulating material, an insulating material whose hardness is lower than that of the insulating material of the first insulating layer, and at least the first insulating layer. a substrate body formed by laminating a second insulating layer having an adhesive layer on the surface of the side adjacent to the insulating layer, and the penetrations conductor formed on the second insulating layer, the first in the first insulating layer A connection conductor formed on the surface adjacent to the two insulating layers and in contact with the end face of the through conductor, and a hardness difference between the insulating material of the first insulating layer and the insulating material of the second insulating layer at least is at 100Hv or more, the second insulating layer includes at least the pressure-sensitive layer of a thermoplastic resin on the surface becomes and thickness following 3μm on the side adjacent to the first insulating layer, the thickness of the connecting conductor Is 2 μm or less, and part of the adhesive layer includes the connection conductor. A convex portion is formed by pushing up the body and pushing up the surface of the insulating material of the second insulating layer facing the connecting conductor.

According to this, when the first insulating layer and the second insulating layer having the hardness difference are stacked and further crimped along the thickness direction while further heating, the top of the connection conductor on the first insulating layer side is obtained. Since the amount of the surface side that is pushed into the surface of the second insulating layer adjacent to the first insulating layer is small (shallow), the deformation amount of the second insulating layer is also reduced, so that local destruction such as cracks and breakage is prevented. It is hard to occur. As a result, it is difficult to cause problems such as short-circuit due to deterioration of insulation performance or inadvertent establishment of a conduction path, and thus a multilayer wiring board having stable inspection performance and electrical characteristics is obtained.
In addition, since the second insulating layer made of a thermosetting resin includes an adhesive layer made of a thermoplastic resin and having a thickness of 3 μm or less, the first insulating layer is formed using the adhesive layer. lamination and adhesion (bonding) is that has been made. Because further, the Tomah to form the convex portions on a part of the top surface of the thickness 2μm or less of the connection conductor a second push amount pushed into the resin layer of the insulating layer is rather small, and the adhesive layer The occurrence of cracks is easily prevented in advance.
If the thickness of the connection conductor exceeds 2 μm, the amount of pushing the top surface side of the connection conductor into the second insulating layer increases, and the amount of deformation of the second insulating layer also increases, so this range is excluded. is there. The thickness of the desirable connecting conductor is in the range of 0.7 to 1.0 μm.

The hardness for each insulating material is, for example, the hardness of the ceramic obtained by firing the green sheet when the insulating material is a ceramic green sheet, and when the insulating material is a synthetic resin. This is the hardness after this is cured. The difference in hardness between the two types of insulating materials is at least 100 Hv or more.
The first insulating layer and the second insulating layer include not only a single insulating layer but also a multilayer structure in which a plurality of the same insulating layers are laminated in advance. In the latter form, an internal wiring layer is formed between the unit insulating layers, and a through conductor for leading the internal wiring layer to the surface or another surface facing the surface is formed inside. .
Furthermore, the first insulating layer and the second insulating layer are names due to relatively different hardness, and are not limited to two types, but also include three types of insulating layers having different degrees of hardness.
The diameter of the through conductor is relatively smaller than the diameter of the connection conductor.
Further, the through conductor includes a via conductor and a through-hole conductor.
In addition, the multilayer wiring board is used as an electronic component inspection wiring board, for example, but can be applied to other uses.

According to the present invention, in the substrate body, the insulating material of the first insulating layer is made of ceramic and the insulating material of the second insulating layer is made of resin, or the first insulating layer and the second insulating layer are insulated. Also included is a multilayer wiring board in which both materials are made of resins having different hardnesses, or both the insulating materials of the first insulating layer and the second insulating layer are made of ceramics having different hardnesses. .
According to this, for example, when the first insulating layer made of ceramic and the second insulating layer made of resin are laminated and further pressure-bonded while heating, the connection conductor formed on the surface of the first insulating layer is the second. It becomes difficult to deform the surface on the adjacent side in the insulating layer. Alternatively, when the first insulating layer and the second insulating layer made of resins having different hardnesses or ceramics having different hardnesses are laminated, the connection conductor is less likely to deform the surface on the second insulating layer side as described above. . Therefore, the multilayer wiring board is excellent in reliability as described above.
Examples of resins having different hardnesses include polyimide and polyethylene naphthalate, and examples of ceramics having different hardnesses include alumina and glass-ceramic. For example, even if the resins are of the same type, such as an epoxy resin, they can be applied when their hardnesses are different.
Moreover, when measuring the hardness (Hv) between resin, it is desirable to carry out according to JISR1610.

Pressurized forte, the present invention, the connection conductors formed on the surface of the first insulating layer, Ti thin film layer and the Cu thin layer, Cr thin film layer and the Cu thin layer, Ti thin film layer and the Mo thin film layer, Cr thin film layer and Mo thin film layer, Ti thin film layer and the Mo thin film layer and the Cu thin film layer, or consist of a laminate of any of Cr thin film layer and the M o thin layer Cu thin layer, multi-layer wiring board (claim 3) also includes It is.
According to this, the thickness is relatively uniform at 2 μm or less, and the electrical connection with the end face of the through conductor exposed on the adjacent surface on the second insulating layer side is also a reliable connection terminal. Therefore, it is possible to remarkably reduce the possibility of occurrence of cracks or the like during heating and pressure bonding (adhesion) after the lamination described above.
The thin film layers of Ti, Cr, Mo, and Cu are preferably formed by physical vapor deposition such as sputtering or PVD as will be described later.

On the other hand, the method for manufacturing a multilayer wiring board according to the present invention (Claim 4) includes the step of forming a first insulating layer having an insulating material and a first through conductor, and the first through-hole on the surface of the first insulating layer. A step of forming a connection conductor having a thickness of 2 μm or less connected to the conductor, a second through conductor, and an insulating material having a hardness that is lower by at least 100 Hv or more than the hardness of the insulating material of the first insulating layer; Forming a second insulating layer having an adhesive layer made of a thermoplastic resin having a thickness of 3 μm or less on the surface of the laminated side adjacent to the insulating layer; and forming the second conductive layer on the laminated side surface of the second insulating layer. The first insulating layer and the second insulating layer are laminated so that the exposed end surface of the second through conductor is in contact, and further heated and pressure-bonded, and pushed up to a part of the adhesive layer above the connection conductor. It is, and absolute of the second insulating layer opposite to the connecting conductor And a step of forming a substrate body having a convex portion that pushes up the surface of the edge member .
According to this, in the step of laminating the first insulating layer and the second insulating layer having the hardness difference and heating and pressing to form the substrate body, the top of the connection conductor on the first insulating layer side is formed. Since the peripheral portion (edge) of the surface hardly bites into the surface of the second insulating layer on the side adjacent to the first insulating layer, and part of the adhesive layer remains as the convex portion, local destruction such as cracks and breaks Is unlikely to occur. As a result, it is possible to provide a multilayer wiring board with stable inspection performance and electrical characteristics, since problems such as deterioration of insulation performance and short circuits due to careless conduction paths do not occur.
Moreover, when the first insulating layer and the second insulating layer are laminated and pressure-bonded, the adhesive layer remains with a relatively uniform thickness of 3 μm or less between the two insulating layers. The peripheral portion (edge) on the surface does not enter the insulating material on the second insulating layer side, and the insulating material is not easily deformed.

Note that the step of forming the connection conductor is performed by appropriately combining sputtering of Ti, Cr, Mo, and Cu.
Moreover, when the starting material of the insulating layer of the first insulating layer or the second insulating layer is a ceramic green sheet, the green sheet is fired into a ceramic until the laminating and pressing step, When the starting material is, for example, an applied epoxy resin or the like, a curing (curing) process is performed before the above-described step.
Furthermore, the contact between the top surface of the connection conductor and the end surface of the second through conductor is made possible by pressure bonding after lamination in the step of forming the substrate body.

Further, the present invention, the insulating material of the first insulating layer is a ceramic, and insulating material of the second insulating layer is ing from the resin, a method for manufacturing a multilayer wiring board (claim 5) is also included.
According to this, the occurrence of such prior mentioned the crack can be more reliably suppressed, may also contribute to the improvement of productivity.

Sectional drawing which shows the outline of the multilayer wiring board of one form by this invention. The partial expanded sectional view of the dashed-dotted line part X in FIG. Schematic which shows the manufacturing process for obtaining the said multilayer wiring board. Schematic which shows the manufacturing process following FIG. Schematic which shows a different manufacturing process. Schematic which shows the manufacturing process following FIG. Schematic which shows the manufacturing process following FIG. 4, FIG. Schematic which shows the manufacturing process following FIG.

Hereinafter, modes for carrying out the present invention will be described.
FIG. 1 is a sectional view schematically showing a multilayer wiring board 1 according to an embodiment of the present invention.
The multilayer wiring board 1 is a wiring board for inspecting electronic components. As shown in FIG. 1, a lower-layer first insulating layer 3 made of ceramic layers (insulating materials) 31 and 32, and the first insulating layer 3. And a second insulating layer 4 on the upper layer side composed of resin layers (insulating materials) 41, 42 of thermosetting resin such as polyimide having a hardness lower than that of the ceramic layers 31, 32, A substrate body 2 having a front surface 5 and a back surface 8 is provided.
The difference in hardness between the ceramic layers 31 and 32 and the resin layers 41 and 42 is about 500 Hv.
In the second insulating layer 4 on the upper layer side, a plurality of via conductors (penetrating conductors) 43 that individually penetrate the resin layers 41 and 42 are formed, and on the surface 7 on the side adjacent to the first insulating layer 3 on the lower layer side. The lower end surface of the via conductor 43 is exposed. Further, the upper surface of the via conductor 43 is exposed on the surface 5 of the substrate body 2, and the via conductor 43 and the inspection terminal 9 formed on the surface 5 are connected. A probe 20 is attached to the inspection terminal 9 later.
As shown in FIGS. 1 and 2, an adhesive layer 14 that is included in the resin layer 41 and is made of a thermoplastic resin and adheres the resin layers 41 and 42 is located between the resin layers 41 and 42. In addition, a wiring layer (not shown) connected to the upper and lower via conductors 43 is formed at the same level as the adhesive layer 14. In the lower resin layer 41, the adhesive layer 14 included on the surface 6 side adjacent to the first insulating layer 3 bonds the first insulating layer 3 and the second insulating layer 4.
2 is a partially enlarged cross-sectional view of a dot-and-dash line portion X in FIG.

On the other hand, the first insulating layer 3 on the lower layer side is formed with a plurality of via conductors 33 concentrically penetrating the ceramic layers 31 and 32, as shown in FIG. 2 is connected to an external terminal 13 formed on the rear surface 8 of the second. Between the ceramic layers 31 and 32, for example, a via cover described later is formed between upper and lower via conductors V.
Further, as shown in FIGS. 1 and 2, in the first insulating layer 3, a plurality of surfaces 7 adjacent to the second insulating layer 4 on the upper layer side are connected to the upper end surface of each via conductor 33. Connecting conductors 10 are individually formed. The connecting conductor 10 has a thickness 10t of 2 μm or less, and is, for example, a flat cylindrical body having a two-layer structure of a Ti thin film layer 11 on the lower layer side and a Cu thin film layer 12 on the upper layer side. The diameter of the connection conductor 10 is about 1.2 to 3 times larger than the diameters of the upper and lower via conductors 33 and 43.

The connection conductor 10 is composed of two layers, a Cr thin film layer and a Cu thin film layer 12, a Ti thin film layer 11 and a Mo thin film layer, a Cr thin film layer and a Mo thin film layer, and a Ti thin film layer 11. And three layers of Mo thin film layer and Cu thin film layer 12, or three layers of Cr thin film layer, Mo thin film layer, and Cu thin film layer 12. Further, the thickness 10t of the connection terminal 10 is controlled to be 2 μm or less when the Ti thin film layer 11 and the Cu thin film layer 12 are formed by sputtering described later.
Further, as shown in FIG. 2, a part of the adhesive layer 14 between the first and second insulating layers 3 and 4 is slightly pushed up above the peripheral portion of the top surface of the connection conductor 10, and the connection conductor The convex part 45 which pushed up the surface of the resin layer 41 facing 10 in a ring shape is formed.

According to the multilayer wiring board 1 as described above, when the first insulating layer 3 and the second insulating layer 4 are laminated and further pressed together in the thickness direction while further heating, the first insulating layer 3 side Since the peripheral portion of the top surface of the connection conductor 10 is less pushed into the surface 6 of the second insulating layer 4 adjacent to the first insulating layer 3, the deformation of the second insulating layer 4 is reduced. In the second insulating layer 4, the resin layers 41 and 42 are less likely to be locally broken such as cracks and breaks. As a result, problems such as deterioration of the insulating performance of the resin layer j1 and the like constituting the second insulating layer 4 and a short circuit due to an inadvertent conduction path in the second insulating layer 4 are less likely to occur. Accordingly, the multilayer wiring board 1 has stable inspection performance and electrical characteristics.
As described above, the first insulating layer 3 and the second insulating layer 4 are a combination in which both insulating materials are made of resins having different hardnesses, or ceramics in which both insulating materials are different in hardness. It may be a combination.
The multilayer wiring board 1 can be applied to applications other than the above as long as it includes the first insulating layer 3, the second insulating layer 4, the via conductors 33 and 43, and the connection conductor 10.

Below, the manufacturing method of the said multilayer wiring board 1 is demonstrated.
First, the manufacturing process of the second insulating layer 4 will be described with reference to FIGS.
First, as shown in FIG. 3A, resin layers 41 and 42 made of polyimide having a thickness of 30 μm, in which a copper foil 15 having a thickness of 5 μm is individually attached to the surface in advance, are prepared. A plurality of through holes 44 having an inner diameter of about 50 μm were formed by irradiation with laser light. The through hole 44 may be formed by punching instead of the laser processing. The resin layers 41 and 42 were previously provided with a thermoplastic resin adhesive layer 14 having an average thickness of 3 μm.
Next, as shown in FIG. 3B, a conductive paste containing Ag powder is filled into each through hole h by screen printing to form via conductors (second through conductors) 43 individually. did. The conductive paste may include Cu powder instead of Ag powder.

Next, after a dry film (not shown) made of a photosensitive resin (for example, epoxy resin) is attached to the entire surface of each of the copper foils 15 of the resin layers 41 and 42, the film is copied in a predetermined pattern. Exposure and development.
As a result, as shown in FIG. 4A, resist patterns 16 and 17 having a predetermined pattern connected to the upper end surface of the via conductor v were formed on each of the copper foils 15 of the resin layers 41 and 42. Further, the copper foil 15 exposed between the patterns 16 and 16 and the bottom surface between the patterns 17 and 17 was removed by etching. As a result, as shown in FIG. 4B, on the surface of the resin layers 41 and 42, a part of the copper foil 15 remains following the pattern and is connected to each via conductor 43 individually. Terminal 9 or wiring layer 18 was formed. The patterns 16 and 17 were also peeled off after etching.

Next, the manufacturing process of the first insulating layer 3 will be described with reference to FIGS.
A ceramic slurry is prepared by previously mixing alumina powder, binder resin, solvent, plasticizer, and the like at a predetermined ratio, and the slurry is formed into a sheet shape by a doctor blade method. Green sheets (hereinafter simply referred to as green sheets) 31 and 32 were produced.
Next, as shown in FIG. 5A, a plurality of through holes 34 having an inner diameter of about 180 μm were formed by irradiating laser at each predetermined position on the green sheets 31 and 32. The through hole 34 may be formed by punching instead of laser processing.

Next, as shown in FIG. 5B, the inside of each through hole 34 is filled with a conductive paste containing W powder by screen printing, and unfired via conductors (first through conductors) 33 are individually provided. Formed. Note that the conductive paste may include Mo powder instead of W powder. Further, when the green sheets 31 and 32 are glass-ceramics for low-temperature firing, the conductive paste containing Ag powder or Cu powder is used.
Further, as shown in FIG. 6 (a), the conductive paste similar to the above is screen-printed at predetermined positions on the front and back surfaces of the green sheet 31 on the lower layer side, and the unfired via cover 19 and the connecting conductors 13 And via conductors 33 are individually connected.
Next, the green sheet 32 in which the via conductors 33 are formed and the green sheet 31 in which the via conductors 33, the connection conductors 13, and the via covers 19 are formed are laminated and pressure-bonded, and then the obtained laminate is obtained. Firing was performed at a predetermined temperature.
As a result, the green sheets 31 and 32 are integrated as the fired ceramic layers 31 and 32, and conductors such as the via conductors 33 are fired at the same time, and as shown in FIG. A ceramic laminate similar to 3 was obtained.

After the surface 7 of the ceramic layer 32 after firing was flattened by polishing, two-stage sputtering was performed on the position above the via conductor 33 where the upper end surface is exposed on the surface 7. That is, as shown on the left side in FIG. 6B, after the Ti thin film layer 11 having a thickness of less than 1 μm is formed by the first sputtering, as shown on the right side in FIG. A Cu thin film layer 12 having the same thickness was formed above the Ti thin film layer 11 by sputtering. As a result, a plurality of connection conductors 10 having a thickness of 2 μm or less were formed on the surface 7 of the ceramic layer 32, and the first insulating layer 3 was obtained.
Subsequently, as shown in the upper part of FIG. 7, the resin layers 41 and 42 were laminated and pressure-bonded via the adhesive layer 14 positioned between them to form the second insulating layer 4. At this time, a part of the adhesive layer 14 was pushed up above the internal wiring layer 18.
Further, as indicated by an arrow in FIG. 7, the second insulating layer 4 is laminated on the surface 7 of the first insulating layer 3, and the via conductor 43 on the second insulating layer 4 side is provided on the top surface of each connection conductor 10. After adhering via the adhesive layer 14 disposed on the surface 6 side of the second insulating layer 4 adjacent to the first insulating layer 3 so that the lower end surface of the second insulating layer 4 is in contact with the first insulating layer 3, it was pressure-bonded (adhered) while heating. .

As a result, as shown in FIG. 8A, the multilayer wiring board 1 including the substrate body 2 having the front surface 5 and the back surface 8 composed of the first insulating layer 3 and the second insulating layer 4 was formed. In addition, in the heating and pressure bonding (adhesion) steps subsequent to the lamination, as shown in FIG. 8 (b) in which the one-dot chain line portion Y in FIG. 8 (a) is enlarged, the connection conductor 10 having a thickness 10t of 2 μm or less. Above the top surface, a part of the adhesive layer 14 located on the first insulating layer 3 side of the second insulating layer 4 is pushed up by the connecting conductor 10 in a small amount, and the resin of the second insulating layer 4 The deformation only entered the layer 41 to a small extent. Therefore, as indicated by the one-dot chain line arrow in FIG. 8B, the peripheral portion (edge) on the top surface of the connection conductor 10 is large in the resin layer 41 forming the surface 6 of the second insulating layer 4. There were no cracks caused by biting.
Finally, electrolytic or electroless Ni plating and electrolytic or electroless Au plating are sequentially applied to the surfaces of the inspection terminal 9 located on the front surface 5 of the substrate body 2 and the external terminal 13 located on the back surface 8, and the Ni plating film and A multilayer wiring board 1 for electronic component inspection could be obtained by covering an Au plating film (both not shown).

According to the method for manufacturing the multilayer wiring board 1 as described above, in the step of forming the substrate body 2 by laminating the first insulating layer 3 and the second insulating layer 4 and heating and pressing (bonding) them. Since the peripheral portion of the top surface of the connection conductor 10 on the first insulating layer 3 side does not greatly deform the resin layer 41 of the second insulating layer 4, local destruction such as cracks and breakage did not occur. As a result, problems such as deterioration of the insulation performance of the resin layer 41 and short circuits due to careless conduction paths have been reduced, and the multilayer wiring board 1 having stable inspection performance and electrical characteristics can be provided.
In addition, the inspection terminal 9 provided on the surface 5 of the substrate body 2 is formed by sequentially laminating, for example, a Ti thin film, a Mo thin film, and a Cu thin film by sputtering in the same manner as the connection terminal 10, and electrolytic or You may form in the form which coat | covered Cu plating film, Ni plating film, and Au plating film by electroless metal plating.
The probe 20 is attached to each inspection terminal 9 later.

In the following, specific examples of the present invention will be described together with comparative examples.
First, a plurality of sets of resin layers 41 and 42 having the copper foil 15 on the front surface and the adhesive layer 14 on the back surface are prepared in the same manner as described above, and through holes 44 having the same inner diameter are formed at these same positions, The via conductors 43 were formed by filling the holes h with the same conductive paste as described above. The resin layers 41 and 42 were laminated and pressure-bonded with the adhesive layer 14 having an average thickness of 3 μm included in each back surface to form a plurality of sets of second insulating layers 4.
On the other hand, a plurality of sets of green sheets 31 and 32 having alumina as a main component and a thickness of 300 μm were prepared, and each set was stacked and fired to form a plurality of sets of first insulating layers 3. After polishing the surface 7 of the first insulating layer 3 in each group under the same conditions, two layers of the Ti thin film 11 and the Cu thin film 12 are formed by performing the same two-stage sputtering for each predetermined position on the surface 7. As shown in Table 1, the connection conductor 10 was formed in which the entire thickness was changed in seven steps from 1.0 μm to 5.0 μm.

Next, on the connecting conductor 10 on the surface 7 of the first insulating layer 3, the top surface of the connecting conductor 10 on the first insulating layer 3 side is exposed on the surface 6 on the second insulating layer 4 side. After laminating the first insulating layer 3 and the second insulating layer 4 so as to be in contact with the end face, a plurality of sets of multilayer wiring boards (1) were obtained by applying the same pressure while heating at the same temperature. A total of 70 multilayer wiring boards (1) for each thickness of the connecting conductor 10 were manufactured.
The substrate body 2 of each multilayer wiring board (1) is cut at the position of the connection conductor 10, and from the peripheral portion (edge) on the top surface of the connection conductor 10 toward the resin layer 41 of the adjacent second insulating layer 4, The presence or absence of cracks or breaks was observed both visually and with a magnifying glass (10 times). In this observation, the presence / absence of a crack or the like (determined as “present” if there is one) and the occurrence state thereof are shown in Table 1. In addition, the multilayer wiring board 1 whose thickness of the connection conductor 10 was 1.0-2.0 micrometers was made into the Example, and the multilayer wiring board whose thickness of the connection conductor 10 was 2.5 micrometers or more was made into the comparative example.

According to Table 1, since each multilayer wiring board 1 of the example had a thickness of the connection conductor 10 of 1.0 to 2.0 μm, no cracks or breakage occurred. This is because the thickness of the connection conductor 10 is 2 μm or less, and therefore, when the first and second insulating layers 3 and 4 are stacked and then crimped while heating, the peripheral portion (edge) on the top surface of each connection conductor 10 Is presumably because the adjacent resin layer 41 was not greatly deformed.
On the other hand, in the multilayer wiring board of the comparative example, when the thickness of the connection conductor 10 is 2.5 μm and 3.0 μm, a minute crack that is not visible but can be discriminated with a magnifying glass is found. When the thickness of 10 was 4.0 μm and 5.0 μm, a visually observable crack was found. In these cases, since the thickness of the connection conductor 10 exceeded 2 μm, the peripheral portion on the top surface of each connection conductor 10 deeply cut into the adjacent resin layer 41 during the heating and pressure bonding depending on the thickness. This is presumably due to the deformation.
The effects of the present invention were confirmed by the multilayer wiring board 1 of the above example.

The present invention is not limited to the embodiment described above.
For example, the first insulating layer and the second insulating layer may each be at least one layer, or when both are two or more layers, the number of layers may be different from each other.
The first insulating layer and the second insulating layer may be a combination in which these insulating materials are made of resins having different hardnesses, or a combination in which the insulating materials are made of ceramics having different hardnesses.
Further, the first insulating layer and the second insulating layer may be three insulating layers having different hardnesses in three stages. For example, the first insulating layer made of a ceramic layer and the first insulating layer made of two kinds of resins having different hardnesses. A combination of two insulating layers and a third insulating layer (two second insulating layers) may be used.
A wiring layer connected to the upper and lower via conductors 33 may be formed between the ceramic layers 31 and 32 of the first insulating layer 3.
Furthermore, the via conductor (through conductor) 43 of the second insulating layer 4 may be a cylindrical through-hole conductor including a space along the axial direction at the center.
In addition, the multilayer wiring board 1 may be in the form of a multi-piece, and the manufacturing method may be a process comprising a multi-piece process.

  According to the present invention, two or more insulating layers having different hardnesses are laminated, and a multilayer wiring that is less likely to cause cracks or the like in the insulating layer on the lower hardness side, which are adjacent to each other and face each other. It is possible to reliably provide a substrate and a manufacturing method thereof.

1 ........... multilayer wiring board 2 ........... board body 3 .......... 1st insulating layer 4 .......... 2nd insulating layer 5-7 ..... surface 10 ......... connection Conductor 10t ……… Thickness 11 ………… Ti thin film layer 12 ………… Cu thin film layer 14 ………… Adhesive layer 31, 32… Ceramic layer / green sheet (insulating material)
33 ………… Via conductor (first through conductor)
41, 42 ... Resin layer (insulating material)
43 ………… Via conductor (through conductor / second through conductor)
45 ………… Convex

Claims (5)

A first insulating layer made of an insulating material; an insulating material having a lower hardness than the hardness of the insulating material of the first insulating layer; and a second layer having an adhesive layer on at least a surface adjacent to the first insulating layer. A substrate body formed by laminating an insulating layer;
And penetrations conductor formed on the second insulating layer,
A connecting conductor formed on the surface of the first insulating layer adjacent to the second insulating layer and in contact with the end face of the through conductor;
Difference in hardness between the insulating material of the insulating material and the second insulating layer of the first insulating layer is at least 100Hv or more,
The second insulating layer includes at least the pressure-sensitive layer of a thermoplastic resin on the surface becomes and thickness following 3μm on the side adjacent to the first insulating layer,
The connecting conductor has a thickness of 2 μm or less,
A part of the adhesive layer is formed with a convex portion that is pushed up above the connecting conductor and pushes up the surface of the insulating material of the second insulating layer facing the connecting conductor.
A multilayer wiring board characterized by that. In the substrate body, the insulating material of the first insulating layer is made of ceramic and the insulating material of the second insulating layer is made of resin, or both the insulating materials of the first insulating layer and the second insulating layer are different in hardness. Or both of the insulating materials of the first insulating layer and the second insulating layer are made of ceramics having different hardnesses,
The multilayer wiring board according to claim 1. The connection conductor formed on the surface of the first insulating layer includes a Ti thin film layer and a Cu thin film layer, a Cr thin film layer and a Cu thin film layer, a Ti thin film layer and a Mo thin film layer, a Cr thin film layer and a Mo thin film layer, and a Cr thin film layer. And the Mo thin film layer and the Cu thin film layer, or the Ti thin film layer, the Mo thin film layer, and the Cu thin film layer.
The multilayer wiring board according to claim 1, wherein the wiring board is a multilayer wiring board. Forming a first insulating layer having an insulating material and a first through conductor;
Forming a connection conductor connected to the first through conductor and having a thickness of 2 μm or less on the surface of the first insulating layer;
A thickness of 3 μm comprising a second through conductor, an insulating material whose hardness is at least 100 Hv or more lower than the hardness of the insulating material of the first insulating layer, and a thermoplastic resin on the surface of the laminated side adjacent to the first insulating layer Forming a second insulating layer having the following adhesive layer;
The first insulating layer and the second insulating layer are laminated so that the end surface of the second through conductor exposed on the surface on the laminated side of the second insulating layer is in contact with the connection conductor, and further heated and pressed. And forming a substrate body having a convex portion that is pushed up above the connection conductor and that pushes up the surface of the insulating material of the second insulating layer facing the connection conductor in a part of the adhesive layer. A process comprising:
A method for manufacturing a multilayer wiring board. The insulating material of the first insulating layer is made of ceramic, and the insulating material of the second insulating layer is made of resin;
The method for producing a multilayer wiring board according to claim 4.

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