JP4077752B2 - Large substrate for multiple acquisition - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a large-sized multiple substrate used for manufacturing a circuit board.
[0002]
[Prior art]
Circuit boards are widely used in semiconductor devices, composite electronic components, and the like, and have been obtained by dividing a large number of large substrates.
A conventional large-sized multiple substrate has a structure in which a dividing groove is formed on the upper surface of a laminate composed of a plurality of insulating layers, and a plurality of substrate regions are formed by the dividing groove. By using the split grooves as a reference, stress is applied to the adjacent substrate regions to be bent, so that the substrate is divided into a plurality of circuit boards. In addition, by forming the dividing groove on the lower surface in addition to the upper surface, it becomes possible to reduce the generation of burrs and chips due to the dividing process, and further, by forming the dividing groove deeply, the effect can be obtained. The thing of the enlarged structure is known (for example, refer patent document 1).
[0003]
As shown in FIGS. 3 (a) to 3 (c), such a large-sized substrate for obtaining a plurality of sheets was obtained by preparing and laminating a plurality of green sheets 31a to 31c containing an inorganic composition. The process of forming the division | segmentation groove | channel 32 extended in the vertical and horizontal direction on the upper surface of the laminated body 31 by pressing the blade edge | tip of a braid | blade vertically, and baking the laminated body 31 on predetermined | prescribed temperature conditions, baking an inorganic composition. And a step of obtaining a plurality of large substrates 30 to be obtained.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 6-310821
[Problems to be solved by the invention]
However, the above-described conventional large-sized base plate 30 for multiple-capturing has an upper surface because the laminate 31 contracts during sintering in the step of firing the laminate 31 and sintering the inorganic composition. The formed dividing groove 32 has a shallow depth and a narrow width, and the side surface of the dividing groove may be rejoined near the deepest portion. Therefore, the divided grooves after sintering become shallow, and there is a disadvantage that burrs and chips are likely to occur during the dividing process.
[0006]
In addition, in order to perform the dividing process smoothly, in a large-sized substrate for taking a plurality of parts having deep dividing grooves, cracks may occur due to handling during mounting. However, the mounting density is also lowered.
[0007]
The present invention has been devised in view of the above-mentioned drawbacks, and its purpose is to provide a large mounting large-capacity substrate with a high mounting density that can reduce the occurrence of burrs, chipping, and cracks due to handling during mounting. Is to provide.
[0008]
[Means for Solving the Problems]
The large-sized multiple substrate according to the present invention includes a first insulating layer formed by sintering the first inorganic composition, a thickness larger than the first insulating layer, and the second inorganic composition as the first insulating layer. A plurality of layers are formed by laminating a second insulating layer that is sintered at a higher temperature than the inorganic composition, and forming a dividing groove on the upper surface of the laminate in which the first insulating layer is positioned as the uppermost layer. a use large substrate, is characterized in that no larger than the thickness T of the first insulating layer disposed depth D ₁ of the said dividing grooves on the uppermost layer of the laminate.
[0009]
Further, in the large-sized substrate for multiple taking according to the present invention, the dividing groove has a V-shaped cross section, and a slit starting from the deepest part of the dividing groove is formed below the dividing groove. It is characterized by.
[0010]
Furthermore, a plurality large substrate for removal of the present invention is characterized in that the length D ₂ of the slit is set to 2% to 30% with respect to the depth D ₁ of the said dividing groove.
[0011]
According to the large-sized substrate for multiple acquisition of the present invention, in the temperature region in which the first insulating layer is sintered at the time of firing the laminated body 1, the surface direction of shrinkage accompanying the sintering of the first insulating layer is unsintered. Since the second insulating layer in the state is suppressed, the first insulating layer is largely sintered in the thickness direction, and the dimension in the plane direction is substantially maintained. Therefore, since the first insulating layer is formed on the uppermost layer, the width of the upper part of the dividing groove is maintained in the same state as that before firing. In addition, by the depth D ₁ of the said dividing grooves without larger than the thickness T of the first insulating layer disposed on the uppermost layer of the laminate, a temperature range for sintering the second insulating layer Then, since the first insulating layer that has been sintered at the upper part of the dividing groove suppresses the surface direction of shrinkage that accompanies the sintering of the second insulating layer, the side surface of the dividing groove undergoes shrinkage along with the sintering. However, since it does not approach, rejoining is unlikely to occur, and it is possible to reduce the occurrence of burrs and chipping due to the division process.
[0012]
In addition, according to the large-sized multiple substrate of the present invention, the first insulating layer, which has been sintered at the upper part of the dividing groove, exerts a stress that spreads the side surface of the dividing groove as it is sintered. In addition, since the dividing groove has a V-shaped cross section, a slit starting from the deepest part of the dividing groove is formed below the dividing groove, so that the dividing groove having a V-shaped cross section is formed. Even if the width of the uppermost layer is narrow, substantially deep division grooves are formed so that the division processing can be easily performed, and the mounting density can be increased.
[0013]
Furthermore, according to the large-sized substrate for multiple acquisition of the present invention, the length D _{2 of the} slit is set to 2% to 30% with respect to the depth D _{1 of the} dividing groove, so It is possible to reduce the occurrence of cracks due to.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view of a large-sized substrate for multiple acquisition of the present invention, FIG. 2 is an enlarged cross-sectional view of the main part of the large-sized substrate for multiple acquisition of FIG. A dividing groove 2 is formed on the upper surface of the substrate.
[0015]
The stacked body 1 has a structure in which a first insulating layer 1a and a second insulating layer 1b are stacked. Wiring conductors (not shown) are formed inside and on the surface of the multilayer circuit board 1, and the surface wiring conductors mainly function as connection pads that serve as mounting portions for electronic component elements. Mainly functions as wiring for electrically connecting each circuit element, and circuit elements such as inductors and capacitors.
[0016]
The 1st insulating layer 1a consists of a 1st inorganic composition, and the 2nd insulating layer 1b consists of a 2nd inorganic composition, As a material of these inorganic compositions, it is a comparatively low temperature of 800 to 1200 degreeC, for example. A glass-ceramic material that can be fired at is preferably used. The glass-ceramic material includes glass powder and ceramic powder. The glass powder is contained in an amount of 30 to 100 parts by weight, and the material excluding the glass powder is the ceramic powder.
[0017]
In the present embodiment, for example, the first insulating layer 1a is made of a material having a composition of 85 parts by weight of glass powder, and the second insulating layer 1b is made of a material having a composition of 55 parts by weight of glass powder.
[0018]
As a specific composition of the glass powder, for example, as essential components, 20 to 70 parts by weight of SiO ₂ , 0.5 to 30 parts by weight of Al ₂ O ₃ , 3 to 60 parts by weight of MgO, and optional components 0 to 35 parts by weight of CaO, 0 to 35 parts by weight of BaO, 0 to 35 parts by weight of SrO, 0 to 20 parts by weight of B ₂ O ₃ , 0 to 30 parts by weight of ZnO, 0 to 10 parts of TiO ₂ A part containing 0 to 3 parts by weight of Na ₂ O and 0 to 5 parts by weight of Li ₂ O is used.
[0019]
The ceramic powder includes at least one selected from Al ₂ O ₃ , SiO ₂ , MgTiO ₃ , CaZrO ₃ , CaTiO ₃ , Mg ₂ SiO ₄ , BaTi ₄ O ₉ , ZrTiO ₄ , SrTiO ₃ , BaTiO ₃ and TiO _2. Used.
[0020]
According to the combination of glass powder and ceramic powder having the above composition, low temperature sintering at 1000 ° C. or less is possible, and silver (melting point 960 ° C.), copper (melting point 1083 ° C.), gold (melting point) as a wiring conductor. 1063 ° C.) or the like, and a low-loss circuit can be created. Also, the dielectric constant can be controlled, which is suitable for circuit miniaturization and low loss due to high dielectric constant, or high-speed transmission due to low dielectric constant. In addition, by controlling various compositions within the above range, the firing shrinkage behavior can be easily controlled and changed.
[0021]
The wiring conductor and via-hole conductor are made of a conductive material containing any one of silver, copper, and gold, and the thickness is set to 5 to 25 μm, for example.
[0022]
The diameter of the via hole conductor can be arbitrarily set. When the thickness of the insulating layer in which the via hole conductor is embedded is 10 to 300 μm, the diameter of the via hole conductor is set to 50 to 300 μm, for example.
[0023]
The above-described large-sized substrate for multiple acquisition includes the following steps.
(Process 1)
The first insulating layer 1a made of the first inorganic composition and the second insulating layer 1b made of the second inorganic composition include, for example, a powder obtained by combining the glass powder and the ceramic powder described above, an organic binder, an organic solvent, and It is a ceramic green sheet obtained by mixing with a plasticizer as necessary to form a slurry, tape-molding the slurry by a doctor blade method or the like, and cutting into a predetermined dimension.
[0024]
At this time, the first insulating layer 1a is formed thinner than the second insulating layer 1b, and the thickness of each of the first insulating layers 1a is set to 2 to 150 μm, for example. Each thickness of 1b is set to 10-300 micrometers, for example.
[0025]
Next, the first insulating layer and the second insulating layer are bonded together, a through hole is formed in the obtained sheet by punching or the like, a conductor paste is filled in the through hole, and the via hole conductor 3 is formed. A wiring conductor 2 is formed by depositing a conductive paste on the main surface of the substrate by screen printing or the like.
[0026]
In this embodiment, for example, the first inorganic composition is made of glass powder, 40 parts by weight of SiO ₂ , ₂ parts by weight of Al ₂ O ₃ , 15 parts by weight of MgO, 1 part by weight of CaO, and 15 parts of BaO. Parts by weight, 20 parts by weight of BO ₃ , 1 part by weight of ZnO, 0.5 part by weight of TiO ₂ , 0.5 part by weight of Na ₂ O, 5 parts by weight of Li ₂ O, and the ceramic powder is MgTiO _3. In the second inorganic composition, the glass powder is composed of 40 parts by weight of SiO ₂ , ₂ parts by weight of Al ₂ O ₃ , 15 parts by weight of MgO, 1 part by weight of CaO, and BaO. 15 parts by weight, BO ₃ 20 parts by weight, ZnO 1 part by weight, TiO ₂ 0.5 part by weight, Na ₂ O 0.5 part by weight, Li ₂ O 5 part by weight, ceramic powder is Al It is made of a material containing 45 parts by weight of ₂ O ₃ .
[0027]
A slurry obtained by adding an acrylic binder as an organic binder and toluene as an organic solvent to these inorganic compositions was prepared to form ceramic green sheets serving as the first insulating layer 1a and the second insulating layer 1b, respectively.
[0028]
The material of the wiring conductor and via-hole conductor is, for example, a paste formed by adding ethyl cellulose as an organic binder and 2-2-4-trimethyl-3-3-pentadiol monoisobutyrate as an organic solvent to silver powder. Using.
[0029]
The sheets thus obtained are laminated according to a predetermined lamination order to form the laminated body 1.
[0030]
(Process 2)
Next, the cutting edge of the blade is pushed vertically into the upper surface of the obtained laminate 1 to form the division grooves 2 so that the depth is larger than the thickness of the first insulating layer 1a. In the present embodiment, the angle of the blade edge of the blade is set to 20 to 40 degrees, and the dividing groove 2 is formed by pushing down to a depth of 7 to 13% of the thickness of the laminated body 1.
[0031]
Such dividing grooves 2 are formed so as to extend in the vertical and horizontal directions, thereby forming a plurality of substrate regions.
[0032]
In the present embodiment, a plurality of dividing grooves 2 are formed in parallel in the vertical and horizontal directions.
[0033]
(Process 3)
And finally, the laminated body 1 in which the above-described divided grooves 2 are formed is integrally fired through a temperature region in which the first inorganic composition is sintered and a temperature region in which the second inorganic composition is sintered. As a result, a large-sized substrate 10 for taking a plurality of pieces as shown in FIG. 1 is obtained.
[0034]
In the large-sized multiple substrate obtained through the above-described steps 1 to 3, the divided grooves 2 are formed on the upper surface of the laminate 1 composed of a plurality of insulating layers, and a plurality of circuit board regions are formed by the divided grooves 2. The circuit board is divided into a plurality of circuit boards by applying a stress such that the adjacent circuit board regions are bent with reference to the formed dividing groove 2.
[0035]
In the temperature region where the first insulating layer 1a is sintered at the time of firing the laminated body 1, the unsintered second insulating layer 1b suppresses the surface direction of shrinkage accompanying the sintering of the first insulating layer 1a. The first insulating layer 1a is largely sintered in the thickness direction so that the dimension in the plane direction is substantially maintained.
[0036]
Therefore, since the first insulating layer 1a is formed in the uppermost layer, the width of the upper portion of the dividing groove 2 is maintained in a state that is substantially the same as that before firing.
[0037]
In addition, by having no greater than the thickness T of the first insulating layer 1a which is disposed a depth D ₁ of the dividing groove 2 on the uppermost layer of the laminate 1, to sinter the second insulating layer 1b In the temperature region, the first insulating layer that has been sintered at the upper portion of the dividing groove 2 suppresses the shrinking surface direction associated with the sintering of the second insulating layer. Therefore, even if the shrinkage works, it does not come close, so rejoining is less likely to occur, and it is possible to reduce the occurrence of burrs and chips due to the division process.
[0038]
In the present embodiment, the first insulating layer 1a is an inorganic composition in which the temperature at which shrinkage starts with sintering is 690 ° C., and the second insulating layer 1b has a temperature at which shrinkage starts with sintering becomes 783 ° C. As a result, it was possible to obtain a large-sized substrate 10 for taking a plurality of pieces having a linear shrinkage rate in the plane direction as small as 3% when the firing shrinkage of the laminate 1 was completed.
[0039]
Regarding the volume shrinkage in firing, the volume shrinkage corresponding to 90% of the total shrinkage amount of the first insulating layer 1a is completed before the second insulation layer 1b starts shrinking in Step 3. It is desirable that 95% or more is completed.
[0040]
Here, the start of shrinkage means that shrinkage accompanying the sintering of the inorganic composition is started. The organic binder contained in the insulating layer is decomposed and removed by heating. At this time, shrinkage of about 0 to 1% may occur. This is due to the removal of the binder, and the inorganic composition is sintered. This is different from the substantial shrinkage caused by. The binder removal temperature varies depending on the binder to be used, but it ends by about 500 ° C. for an acrylic or methacrylic binder and about 600 ° C. for a butyral binder.
[0041]
On the other hand, regarding the shrinkage start temperature in firing, the difference in temperature is preferably 10 ° C. or higher, more preferably 20 ° C. or higher. Through the step 3, the laminated body finishes firing shrinkage. In the present invention, the completion of firing shrinkage means a point when the total volume shrinkage has progressed 99% or more.
[0042]
Further, the first insulating layer 1a that has been sintered at the upper portion of the dividing groove 2 is subjected to a stress that spreads the side surface of the dividing groove 2 with the sintering. In addition, since the dividing groove 2 has a V-shaped cross section, a slit 3 starting from the deepest part of the dividing groove 2 is formed below the dividing groove 2, so that the dividing has a V-shaped section. Even if the width of the uppermost layer of the groove 2 is narrow, the deep dividing groove 2 is formed substantially so that the dividing process can be easily performed, and the mounting density can be increased.
[0043]
Furthermore, in the large-sized substrate 10 for taking multiple pieces of the present embodiment, the length D ₂ of the slit 3 is set to 2% to 30% with respect to the depth D ₁ of the dividing groove 2. It is possible to reduce the occurrence of cracks due to handling.
[0044]
In addition, this invention is not limited to the above-mentioned embodiment, A various change, improvement, etc. are possible within the range which does not deviate from the summary of this invention.
[0045]
For example, in the above-described embodiment, the ceramic green sheet is used for forming the first insulating layer, and this is used by being bonded to the ceramic green sheet used for forming the second insulating layer. The first inorganic composition in paste form is used for forming the first insulating layer, and this is applied directly to the main surface of the ceramic green sheet used for forming the second insulating layer by printing or the like. Anyway. In this case, the first insulating layer having a small thickness can be formed relatively easily by applying a paste or the like, and the first insulating layer is compared with the case where the first insulating layer having a small thickness is made of a ceramic green sheet or the like. There is an advantage that the workability in forming the substrate becomes good and the productivity of the multilayer circuit board can be improved.
[0046]
Further, in the above-described embodiment, the dividing groove is formed on the upper surface of the laminate, but in addition to this, the dividing groove may be formed on the lower surface. This makes it easy to form a fractured surface of the material with high accuracy and to reduce the occurrence of burrs and burrs.
[0047]
【The invention's effect】
According to the large-sized substrate for multiple acquisition of the present invention, in the temperature region in which the first insulating layer is sintered at the time of firing the laminated body 1, the surface direction of shrinkage accompanying the sintering of the first insulating layer is unsintered. Since the second insulating layer in the state is suppressed, the first insulating layer is largely sintered in the thickness direction, and the dimension in the plane direction is substantially maintained. Therefore, since the first insulating layer is formed on the uppermost layer, the width of the upper part of the dividing groove is maintained in the same state as that before firing. In addition, by the depth D ₁ of the said dividing grooves without larger than the thickness T of the first insulating layer disposed on the uppermost layer of the laminate, a temperature range for sintering the second insulating layer Then, since the first insulating layer that has been sintered at the upper part of the dividing groove suppresses the surface direction of shrinkage that accompanies the sintering of the second insulating layer, the side surface of the dividing groove undergoes shrinkage along with the sintering. However, since it does not approach, rejoining is unlikely to occur, and it is possible to reduce the occurrence of burrs and chipping due to the division process.
[0048]
In addition, according to the large-sized multiple substrate of the present invention, the first insulating layer, which has been sintered at the upper part of the dividing groove, exerts a stress that spreads the side surface of the dividing groove as it is sintered. In addition, since the dividing groove has a V-shaped cross section, a slit starting from the deepest part of the dividing groove is formed below the dividing groove, so that the dividing groove having a V-shaped cross section is formed. Even if the width of the uppermost layer is narrow, substantially deep division grooves are formed so that the division processing can be easily performed, and the mounting density can be increased.
[0049]
Furthermore, according to the large-sized substrate for multiple acquisition of the present invention, the length D _{2 of the} slit is set to 2% to 30% with respect to the depth D _{1 of the} dividing groove, so It is possible to reduce the occurrence of cracks due to.
[Brief description of the drawings]
FIG. 1 is a perspective view of the appearance of a large-sized multiple substrate according to an embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view of a main part of the large-sized substrate for taking multiple pieces of FIG. 1;
FIG. 3 is a cross-sectional view for explaining a conventional manufacturing process of a large-sized multiple substrate.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Laminated body 1a ... 1st insulating layer 1g ... 2nd insulating layer 2 ... Dividing groove 3 ... Slit

Claims (3)

A first insulating layer formed by sintering the first inorganic composition, and a thickness greater than that of the first insulating layer, and the second inorganic composition is sintered at a higher temperature than the first inorganic composition. A plurality of large-sized substrates formed by laminating a second insulating layer and forming a dividing groove on the upper surface of the laminate in which the first insulating layer is positioned as the uppermost layer,
Plurality large substrate for removal, characterized in that no larger than the thickness T of the first insulating layer disposed on the uppermost layer of depth D ₁ of the laminate of the dividing groove. 2. The plurality of picks according to claim 1, wherein the dividing groove has a V-shaped cross section, and a slit is formed below the slit starting from the deepest portion of the dividing groove. Large substrate for use. Plurality large substrate for removing of claim 2, characterized in that the length D ₂ of the slit is set to 2% to 30% with respect to the depth D ₁ of the said dividing groove.

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