JP3064273B2 - High frequency porcelain - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board applied to a package for storing semiconductor elements, a multilayer wiring board, and the like, and more particularly to a wiring board which can be co-fired with copper or silver. High frequency porcelain compositions and high frequency porcelain that can be mounted with high reliability on external circuit boards made of organic resin such as chip parts and printed boards, and are used as insulating substrates in wiring boards.
And its manufacturing method.

[0002]

2. Description of the Related Art Heretofore, as a ceramic multilayer wiring board, a wiring board made of a refractory metal such as tungsten or molybdenum formed on the surface or inside of an insulating substrate made of an alumina sintered body has been most widely used. I have.

Further, recently, with the era of advanced information, the frequency band to be used is shifting to higher and higher frequencies. In such a high-frequency wiring board that requires transmission of a high-frequency signal, in order to transmit a high-frequency signal without loss, the resistance of the conductor forming the wiring layer is small, and the dielectric of the insulating substrate in the high-frequency region is low. Low loss is required.

However, conventional tungsten (W),
Refractory metals such as molybdenum (Mo) have high conductor resistance, have low signal propagation speeds, and have difficulty in signal propagation in the high-frequency region of 1 GHz or higher. It is necessary to use low resistance metals such as silver and gold. Since the wiring layer made of such a low-resistance metal has a low melting point and cannot be co-fired with alumina, recently, a so-called glass ceramic made of glass or a composite material of glass and ceramic has been insulated. Wiring boards used as substrates are being developed. For example, as disclosed in Japanese Patent Application Laid-Open No. 60-240135, a multilayer wiring board in which a filler such as Al ₂ O ₃ , zirconia, and mullite is added to a zinc borosilicate glass and co-fired with a low-resistance metal, 5-298
As in Japanese Patent No. 919, a glass ceramic material in which mullite or cordierite is precipitated as a crystal phase has been proposed.

Further, when mounting chip parts such as GaAs on a wiring board such as a multilayer wiring board or a package for housing semiconductor elements, or mounting a wiring board on a printed board containing an organic resin such as a motherboard, an insulating board is required. In order to prevent the mounting part from peeling or cracking due to the stress generated due to the thermal expansion difference between the chip part and the printed circuit board, the thermal expansion coefficient of the It is desired to be close to that of

Therefore, the present applicant has previously disclosed in Japanese Patent Laid-Open No. 9-17 / 1997.
As disclosed in Japanese Patent No. 904, it has been proposed that the use of crystallizable lithium silicate glass can increase the thermal expansion coefficient of an insulating substrate.

[0007]

However, the conventional glass ceramic has a thermal expansion coefficient of 3 to 5 even if it can be co-fired with a low-resistance metal such as copper, silver or gold.
ppm / ° C, which is as low as about 1 ppm / ° C, the reliability of mounting when mounting chip parts such as GaAs (coefficient of thermal expansion: 6 to 7.5 ppm / ° C) or printed circuit boards (coefficient of thermal expansion: 12 to 15 ppm / ° C) The properties were low and were not practically satisfactory.

In the method using a glass containing an alkali metal as disclosed in Japanese Patent Application Laid-Open No. Hei 9-17904, when exposed to a high-temperature and high-humidity atmosphere for a long time, the alkali metal reacts with the moisture in the atmosphere to produce a surface. In some cases, a silicate crystal phase is precipitated and the surface is deteriorated.

Conventional glass ceramics have not been specifically studied as insulating substrates for wiring boards using high-frequency signals such as millimeter waves, and most of them have high dielectric loss and have satisfactory high-frequency characteristics. Was not.

Therefore, the present invention can be fired at 800 to 1000 ° C., which can be multilayered using gold, silver and copper as wiring conductors, and has a thermal expansion coefficient close to that of chip parts such as GaAs or a printed circuit board. It is an object of the present invention to provide a porcelain which can be controlled to the above-mentioned coefficient of thermal expansion, has a low dielectric constant and a low dielectric loss even in a high frequency region, a method for producing the same, and a high frequency porcelain composition which can be produced therefrom.

[0011]

Means for Solving the Problems As a result of diligent studies of the above-mentioned problems, the present inventor has found that either SiO ₂ , Al ₂ O ₃ , MgO and CaO, or SiO ₂ , Al ₂ O ₃ , MgO
For a glass capable of precipitating a diopside-type oxide crystal phase containing O, SrO and CaO, a composition in which an oxide containing Mg and / or Zn and Ti is blended at a specific ratio is used. Is fired at a temperature of 800 to 1000 ° C. to obtain a low dielectric constant
The present inventors have found that a porcelain having a low dielectric loss can be obtained even in a high-frequency region of 1 GHz or more, which can be controlled to a coefficient of thermal expansion similar to the coefficient of thermal expansion of a chip component such as s or a printed circuit board, and the present invention.

[0012]

[0013]

[0014]

[0015]

[0016]

The high frequency porcelain of the present invention produced using the above porcelain composition has at least Mg, Ca, S
i, a diopside oxide crystal phase containing Al, Mg
And / or a composite oxide crystal phase containing Zn and Ti, and has a thermal expansion coefficient of 7 ppm / ° C. or more from room temperature to 400 ° C., a dielectric constant of 8 or more, and 60 to 77.
The dielectric loss at 30 GHz is 30 × 10 ⁻⁴ or less.

[0018]

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION (First Glass Composition) The first high frequency porcelain composition of the present invention comprises SiO ₂ , Al ₂ O ₃ ,
Glass containing MgO and CaO and capable of precipitating a diopside-type oxide crystal phase (hereinafter abbreviated as first glass): 60 to 99% by weight; Mg and / or Zn as a filler; and Ti Oxides in an amount of 1 to 40% by weight.

The composition of each component was limited to the above range.
If the first glass is less than 60% by weight, 100
It is difficult to densify the porcelain by firing at a temperature of 0 ° C. or less, and if it exceeds 99% by weight, the crystallization of the glass becomes insufficient, a glass phase having a large dielectric loss remains, and the high frequency of the porcelain becomes high. This is because the dielectric loss at the point increases.
A particularly desirable range for the first glass is 70-90% by weight.
It is.

That is, Mg added as a filler
If the amount of the composite oxide containing Zn and Ti is less than 1% by weight, the residual ratio of the glass increases, and the dielectric loss increases. Conversely, if the amount exceeds 40% by weight, 1000 ° C. or lower Cannot be densified at the firing temperature of A desirable range of the amount of the oxide containing Mg and / or Zn and Ti is 10 to 30% by weight.

Here, the first glass desirably has a softening point of 500 to 800 ° C. and a composition of 45 to 55% by weight of SiO ₂ , _{3 to} 10% by weight of Al ₂ O ₃ , and MgO 13. It is desirable that the ratio is about 24% by weight and about 20 to 30% by weight of CaO.

In order to increase the precipitation ratio of the diopside oxide crystal phase from the first glass, the total amount of CaO and MgO in the glass is 35 to 50% by weight.
It is desirable that

(Second Glass Composition) A second high frequency porcelain composition of the present invention comprises SiO ₂ , Al ₂ O ₃ , MgO,
55-99% by weight of a glass containing SrO and CaO and capable of precipitating a diopside oxide crystal phase (hereinafter abbreviated as a second glass), Mg and / or Zn
And an oxide containing Ti at a ratio of 1 to 45% by weight.

The reason for limiting each component composition to the above range is as follows.
If the second glass is less than 55% by weight, 100
It is difficult to densify the porcelain by firing at a temperature of 0 ° C. or less, and if it is more than 99% by weight, the crystallization of the glass becomes insufficient and the dielectric loss of the porcelain at a high frequency increases. . A particularly desirable range for the second glass is 7
0 to 90% by weight.

That is, Mg added as a filler
And / or the amount of oxide containing Zn and Ti is 1
If the amount is less than 45% by weight, the residual ratio of the second glass increases, and the dielectric loss increases. On the other hand, if the amount exceeds 45% by weight, sintering becomes difficult, and densification occurs at a firing temperature of 1000 ° C. or lower. Can not do. Mg and / or Zn and T
The desirable range of the amount of the oxide containing i is 10 to 30.
% By weight.

Here, the second glass desirably has a softening point of 500 to 800 ° C., and has a composition of 45 to 55% by weight of SiO ₂ , _{3 to} 10% by weight of Al ₂ O ₃ , and MgO 13. -24% by weight, SrO 10-24% by weight, and CaO 8-20% by weight.

In order to increase the precipitation ratio of the diopside oxide crystal phase from the above glass, it is desirable that the total amount of CaO and MgO in the second glass is 20 to 40% by weight.

The SrO contained in the second glass composition is either dissolved in the crystal phase in the sintered porcelain or present in the glass.

The oxides containing Mg and / or Zn and Ti added to the above two types of glass as fillers include oxides of MgO, ZnO, TiO ₂ alone and two or more types of oxides. may be a composite oxide, in particular _{MgTiO 3, ZnTiO 3, (Mg} , Zn) TiO 3
It is desirable to have the form.

(Method of Manufacturing Porcelain) In order to manufacture a porcelain using the high-frequency ceramic composition of the present invention, a crystal made of the first or second glass capable of precipitating the diopside-type oxide crystal phase is used. Fossilized glass, Mg and / or Zn,
Using a mixed powder of the above composition comprising an oxide containing Ti and a doctor blade method or a calendar roll method,
Alternatively, after forming a molded body having a predetermined shape by a known molding method such as a rolling method and a press molding method, the molded body is 800 to 10
It can be manufactured by firing in an oxidizing atmosphere or a non-oxidizing atmosphere at 00 ° C.

According to the present invention, the sintering temperature of the porcelain can be reduced by using the second glass, and the sintering temperature can be reduced to 1000 ° C. or less, particularly 950 ° C. or less, and further 930 ° C. or less. This facilitates simultaneous firing with copper and / or silver, which is frequently used as a wiring layer of a high-frequency wiring board, as described later.

(Porcelain) The porcelain composition of the above embodiment is 80%
A relative density of 9 is obtained by firing in a temperature range of
It can be densified to 7% or more. The total composition of the porcelain formed by this is SiO 2 when the total amount of each metal element of Si, Al, Mg and Ca is 100% by weight in terms of oxide. ₂ to 30 to 50% by weight, Al ₂ O
₃ to 5% by weight, MgO to 10 to 14% by weight, CaO
Proportion of 15 to 21 wt%, or, the SiO ₂ from 30 to 4
5 wt%, the Al ₂ O ₃ 3 to 9 wt%, 15 to the MgO
20% by weight, SrO 10-20% by weight, CaO10
Desirably, it comprises 16% by weight.

Generally, the glass phase containing Al ₂ O ₃ or SiO ₂ has a low thermal expansion coefficient of 4 to 5 ppm / ° C. On the other hand, the diopside oxide crystal phase of Ca (Mg, Al) (Si, Al) ₂ O ₆ has a high thermal expansion characteristic of about 8 to 9 ppm / ° C. High thermal expansion can be achieved by precipitating a pside oxide crystal phase. The diopside oxide crystal phase is a material having a dielectric constant of 6 to 8 and having a small dielectric loss in a high frequency band.

According to the present invention, the presence of a predetermined amount of the composite oxide crystal phase containing Mg and / or Zn and Ti in the above-mentioned high frequency porcelain allows the thermal expansion coefficient from room temperature to 400 ° C. to be increased. 7 ppm / ° C. or more, particularly 8 ppm / ° C. or more, and a dielectric constant of 8 or more, particularly 9 or more,
Dielectric loss at ~ 77 GHz is 30 × 10 ^-4 or less, especially 2
It can be controlled to a characteristic of 0 × 10 ⁻⁴ or less.

As a result, the difference in the coefficient of thermal expansion between the porcelain and an external circuit board made of an organic resin such as a chip component such as GaAs and a printed board can be reduced, so that when the porcelain of the present invention is used as an insulating substrate of a wiring board, The reliability of mounting can be improved.

Also, by increasing the dielectric constant of porcelain,
By using the porcelain for high frequency of the present invention as an insulating substrate of a wiring board, the wiring width can be reduced in terms of impedance matching, so that high-density mounting is possible and the wiring board can be downsized. . In addition, 6 of porcelain
Since the dielectric loss at 0 to 77 GHz can be reduced,
Signal transmission characteristics in a high-frequency band, particularly in a millimeter-wave band, are improved.

Further, as shown in the schematic diagram of the porcelain structure of FIG. 1, the porcelain produced as described above has a dioptric phase containing at least Mg, Ca, Si and Al precipitated from glass as a crystal phase. Side-type oxide crystal phase Ca (M
g, Al) (Si, Al) ₂ O ₆ (DI)
And / or a composite oxide crystal phase containing Zn and Ti.

As the composite oxide crystal phase containing Mg and / or Zn and Ti, MgTiO ₃ , Mg
(1-x) ilmenite crystal phase represented by ZnxTiO ₃ (I), or _{Mg 2 TiO 4, Zn 2 TiO} 4
Exists in porcelain as a spinel type crystal phase (SP) represented by Furthermore, the porcelain contains a TiO ₂ crystal phase (Ti).
May be present. Thus, the dielectric constant of the porcelain can be increased.

In addition, the diopside and the above Mg
Since the composite oxide crystal containing Zn and / or Ti has a small dielectric loss in a millimeter wave band, the dielectric loss of the porcelain can be reduced.

In the porcelain, Ca ₂ MgSi ₂ O ₇ (akermanite),
CaMgSiO ₄ (Monticellite), Ca
Similar phases with high thermal expansion, such as ₃ MgSi ₂ O ₈ (merwinite), may precipitate.

With the above configuration, the thermal expansion coefficient of the porcelain
pm / ° C. or more, especially 8 ppm / ° C. or more, and the dielectric constant of the porcelain is increased to 8 or more, especially 9 or more, and 6
Dielectric loss at 0 to 77 GHz is 30 × 10 ⁻⁴ or less,
In particular, it can be set to 20 × 10 ⁻⁴ or less.

The porcelain composition of the present invention has a low dielectric loss in a high frequency band, and therefore has a dielectric loss of 1 GHz or more, especially 20 GHz or more, more preferably 50 GHz or more, and even 70 GHz.
It is suitable for forming the insulating layer of the high-frequency wiring board described above.

When the high frequency porcelain of the present invention is used as an insulating layer of a wiring board, the coefficient of thermal expansion of the insulating substrate from room temperature to 400 ° C. is close to the coefficient of thermal expansion of a mounted chip component or a printed circuit board. As mentioned earlier,
It is desirable that the composition and structure of the porcelain constituting the substrate be controlled and appropriately adjusted.

When the thermal expansion coefficient of the insulating substrate is different from that of the mounted chip component or the printed circuit board, the temperature of the chip component or the like is increased by repeated temperature cycles during solder mounting or by stopping the operation of the semiconductor element. This is because stress due to the difference in thermal expansion is generated in the mounting portion between the printed circuit board and the package, and cracks and the like are generated in the mounting portion, thereby impairing the reliability of the mounting structure.

More specifically, the difference in the coefficient of thermal expansion between the GaAs-based chip component and the GaAs-based chip component is 2 ppm / ° C. or less in order to match the GaAs-based chip component. In this case, it is desirable that the difference in the coefficient of thermal expansion from the printed board is 2 ppm / ° C. or less.

(Method of Manufacturing Wiring Board) A method of manufacturing a wiring board having a wiring layer using the high-frequency ceramic composition of the present invention will be specifically described. To the mixed powder comprising the above-described composition, an appropriate organic solvent, a slurry is prepared by mixing with a solvent, and this is conventionally known as a doctor blade method or a calender roll method, or a rolling method,
It is formed into a sheet by a press forming method. Then, after a through-hole is formed in this sheet-like molded body as desired, the through-hole is filled with a metal paste containing at least one of copper, gold, and silver. Then, on the surface of the sheet-like molded body, the thickness of the wiring layer is reduced to 5 to 3 by a screen printing method, a gravure printing method, or the like using the metal paste in a high-frequency line pattern or the like capable of transmitting a high-frequency signal.
Print and apply so that the thickness becomes 0 μm.

Thereafter, a plurality of sheet-like molded bodies are aligned and laminated and pressed, and fired in a non-oxidizing atmosphere such as a nitrogen gas or a nitrogen-oxygen mixed gas at 800 to 1000 ° C. to produce a wiring substrate. be able to. Then, a chip component such as a semiconductor element is appropriately mounted on the surface of the wiring board, and connected to the wiring layer so that signals can be transmitted.

As a connection method, a connection may be made by directly mounting on the wiring layer, or a resin or Ag of about 50 μm may be used.
-The chip component is fixed to the surface of the insulating substrate with an adhesive such as a resin such as epoxy, Ag-glass, or Au-Si, a metal, or a ceramic, and the wiring layer and the semiconductor element are connected by wire bonding or TAB tape.

As the semiconductor element, a chip component such as a Si-based or GaAs-based component can be used, but it is most effective for mounting a GaAs-based chip component in terms of the similarity of the thermal expansion coefficient.

Further, a cap made of an insulating material of the same kind as the insulating substrate, another insulating material, or a metal having good heat dissipation, and having an electromagnetic wave shielding property is provided on the surface of the wiring board on which the semiconductor element is mounted with glass, The semiconductor element may be hermetically sealed by bonding with an adhesive such as a resin or a brazing material.

(Structure of Wiring Board) A specific structure of a package for housing a semiconductor element, which is an example of a high-frequency wiring board in which the porcelain composition of the present invention can be preferably used, and a mounting structure thereof will be described with reference to FIG. explain. FIG. 2 is a schematic cross-sectional view of a semiconductor element storage package, particularly a ball grid array (BGA) type package in which connection terminals are formed of ball-shaped terminals.

Referring to FIG. 2, the package A has a cavity 3 formed by an insulating substrate 1 made of an insulating material and a lid 2, in which a chip component 4 such as GaAs is bonded. Implemented by agent.

Further, on the surface and inside of the insulating substrate 1,
A wiring layer 5 electrically connected to the chip component 4 is formed. The wiring layer 5 is desirably made of a low-resistance metal such as copper, silver, or gold in order to minimize conductor loss when transmitting a high-frequency signal. When transmitting a high-frequency signal of 1 GHz or more to the wiring layer 5, it is necessary to transmit the high-frequency signal without loss. Therefore, the wiring layer 5 includes a known strip line, microstrip line, coplanar line, It is composed of at least one of dielectric waveguide lines.

In the package A of FIG. 2, a connection electrode layer 6 is formed on the bottom surface of the insulating substrate 1 and is connected to the wiring layer 5 in the package A. A ball-shaped terminal 8 is formed on the connection electrode layer 6 with a brazing material 7 such as solder.

The package A is connected to an external circuit board B.
As shown in FIG. 2, a polyimide resin,
An external circuit board B having a wiring conductor 10 formed on the surface of an insulating substrate 9 made of an insulating material containing an organic resin such as an epoxy resin or a phenol resin is mounted via a brazing material. Specifically, the ball-shaped terminals 8 attached to the bottom surface of the insulating substrate 1 in the package A and the wiring conductors 10 of the external circuit board B are brought into contact with each other, and the brazing material 11 such as a solder such as Pb-Sn is used. It is mounted with brazing. Further, the ball-shaped terminal 8 itself may be melted and connected to the wiring conductor 10.

According to the present invention, the chip component 4 such as GaAs is mounted on an external circuit board such as a printed board by brazing or mounting with an adhesive or by brazing with such ball-shaped terminals 8 interposed therebetween. In such a surface mount type package, a thermal cycle is applied to such a mounting structure because a difference in thermal expansion between a chip component such as GaAs and an insulating substrate of an external circuit board can be made smaller than that of a conventional ceramic material. Also in this case, the generation of stress in the mounting portion can be suppressed, and as a result, the long-term reliability of the mounting structure can be improved.

[0058]

EXAMPLES (Example 1) Crystallized glass capable of precipitating two kinds of diopside oxide crystal phases having the following compositions was prepared.

Glass A: SiO ₂ 50% by weight—Al ₂ O
₃ 5.5 wt% -MgO18.5 wt% -CaO26 wt% Glass B: SiO ₂ 52 wt% -Al ₂ O ₃ 5 wt% -
MgO 18% by weight-CaO 25% by weight The average particle size of the crystallized glass powder is 2%.
Using the additive powder shown in Tables 1 and 2 of μm, they were mixed so that the fired porcelain had the compositions shown in Tables 1 and 2.

Then, an organic binder, a plasticizer and toluene were added to the mixture to prepare a slurry.
m green sheets were produced. Then, 10 to 15 green sheets are laminated, and at a temperature of 50 ° C., 100 k
g / cm ² and a thermocompression bonding. The obtained laminate was subjected to a binder removal treatment in a steam-containing / nitrogen atmosphere at 700 ° C., and then fired in dry nitrogen under the conditions shown in Tables 1 and 2 to obtain a porcelain for an insulating substrate.

The obtained ceramics were evaluated for permittivity and dielectric loss by the following methods. The measurement is shape, diameter 2-7mm,
Cut out to 1.5-2.5mm thickness, 60GHz
, And a dielectric cylinder resonator method using a network analyzer and a synthesized sweeper. In the measurement, the dielectric resonator was excited by an NRD guide (non-radiative dielectric line), and the dielectric constant and the dielectric loss were calculated from the resonance characteristics of the TE021 and TE031 modes.

A thermal expansion curve from room temperature to 400 ° C. was taken to calculate a thermal expansion coefficient. Further, the crystal phase in the sintered body was identified from the X-ray diffraction chart. The results are shown in Tables 1 and 2.

For some of the samples, ZrO ₂ powder and CaZrO ₃ were used instead of the composite oxide powder containing Mg and / or Zn and Ti as filler components.
Porcelain was similarly prepared using the powder and evaluated (sample No. 9).
-11, 28-30). In addition, the above-mentioned crystallized glass A, B
Instead, the same evaluation was performed using glass C having the following composition (Sample Nos. 35 and 36).

Glass C: SiO ₂ 10.4% by weight-Al
₂ O ₃ 2.5 wt% -B ₂ O ₃ 45.3 wt% -CaO
35.2 wt% -Na ₂ O6.6% by weight

[0065]

[Table 1]

[0066]

[Table 2]

As is clear from the results in Tables 1 and 2, Si
Sample No. 1 in which the amount of glass A or B containing O ₂ , Al ₂ O ₃ , MgO and CaO exceeds 99% by weight. In Sample Nos. 1 and 19, the dielectric loss exceeded 30 × 10 ⁻⁴ , and the amount of the glass was less than 60% by weight. 13-15,
In Nos. 32 and 33, sintering at a low temperature was difficult, and they were not densified. Sample No. 8-10, 27-29
ZrO ₂ and CaZrO ₃ as filler components to glass
ZrO ₂ and CaZ are contained in the sintered body.
Deposition of rO _{3 and the} like increased dielectric loss.

Sample No. 2 using glass C containing a large amount of B ₂ O ₃ was used as the glass. Sample No. 34 was melted. In No. 35, since the diopside type crystal phase disappeared, a large amount of glass containing boron remained, and the dielectric loss tended to increase.

On the other hand, according to the present invention, a specific amount of M
g and / or Zn, and a sample No. to which an oxide containing Ti was added. 2 to 7, 11, 12, 16 to 18, 2
At 0 to 26, 30, and 31, precipitation of a composite oxide crystal phase containing Mg and / or Zn and Ti was observed in the porcelain, and each had a thermal expansion coefficient of 7 ppm / ° C. or more and a dielectric constant of at least 7. The dielectric loss was 8 or more, and the dielectric loss at 60 to 77 GHz was 30 × 10 ⁻⁴ or less.

(Example 2) For crystallized glasses D and E capable of precipitating two kinds of diopside oxide crystal phases having the following compositions, Tables 3 and 4 having an average particle size of 2 μm are shown in Tables 3 and 4. Using the additive powders shown, the porcelain after firing was mixed so as to have the compositions shown in Tables 3 and 4, to produce a porcelain in the same manner as in Example 1, and evaluated in the same manner. The results are shown in Tables 3 and 4.

Glass D: SiO ₂ 50.2% by weight-Al
₂ O ₃ 5.0% by weight-MgO 16.1% by weight-SrO1
3.6 wt% -CaO15.1 wt% Glass E: SiO ₂ 47.5 wt% -Al ₂ O ₃ 4.9
Wt% -MgO16.1 wt% -SrO20 wt% -C
aO11.5% by weight

[0072]

[Table 3]

[0073]

[Table 4]

As is clear from the results in Tables 3 and 4, Si
Sample No. 2 in which the amount of glass D or E containing O ₂ , Al ₂ O ₃ , MgO, SrO, and CaO exceeds 99% by weight. 3
In Sample Nos. 6 and 52, the dielectric loss exceeded 30 × 10 ⁻⁴ , and in Sample No. 6 in which the amount of glass was less than 60% by weight.
In 47 to 49, 62 and 63, sintering at a low temperature was difficult, and densification was not achieved. Sample No. 42-44,
57 to 59 are ZrO as a filler component to glass.
₂ and CaZrO ₃ , but Z
rO ₂ , CaZrO _3, etc. were precipitated, and the dielectric loss increased.

On the other hand, according to the present invention, a specific amount of M
g and / or Zn, and a sample No. to which an oxide containing Ti was added. 37-41, 45, 46, 50, 5
In Nos. 1, 53 to 56, 60, and 61, precipitation of a composite oxide crystal phase containing Mg and / or Zn and Ti was observed in the porcelain, and all had a thermal expansion coefficient of 7 ppm /
It had excellent characteristics of a dielectric loss of 30 × 10 ^-4 or less at 60 ° C. or more, a dielectric constant of 8 or more, and 60 to 77 GHz.

[0076]

As described above in detail, according to the porcelain composition for high frequency wave of the present invention, since it can be fired at a low temperature of 1000 ° C. or less, a wiring layer made of a low-resistance metal such as copper can be formed. In the high-frequency region, the high-frequency signal has a high dielectric constant and a low dielectric loss, so that a high-frequency signal can be transmitted very favorably without loss. In addition, the porcelain obtained using this composition can be controlled to have a thermal expansion characteristic similar to that of a GaAs chip or a printed circuit board. Therefore, when a GaAs chip is mounted or a printed circuit board having an insulating substrate containing an organic resin is used. When mounted on a motherboard with a brazing material or the like, it has an excellent heat cycle resistance and can provide a highly reliable mounting structure.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining the structure of porcelain obtained by firing a composition of the present invention.

FIG. 2 is a schematic cross-sectional view illustrating an example of a mounting structure of a package for housing a semiconductor element, which is an example of a high-frequency wiring board using a porcelain obtained by firing the composition of the present invention.

[Description of Signs] DI Diopside-type oxide crystal phase I Ilmenite-type crystal phase SP Spinel-type crystal phase G Amorphous (glass) phase Ti titania crystal phase A Semiconductor element storage package B External circuit board 1 Insulating substrate 2 Lid 3 Cavity 4 Chip component 5 Wiring layer 6 Connecting electrode layer 7 Brazing material 8 Ball-shaped terminal 9 Insulating substrate 10 Wiring conductor 11 Brazing material

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification code FI H01P 3/16 H01P 3/16 H05K 1/03 610 H05K 1/03 610D 3/46 3/46 H

Claims (1)

(57) [Claims] A diopside oxide crystal phase containing at least Mg, Ca, Si, and Al; and a composite oxide crystal phase containing Mg and / or Zn and Ti.
And a coefficient of thermal expansion from room temperature to 400 ° C. of 7 ppm /
A high frequency porcelain characterized by having a dielectric loss of 30 × 10 ⁻⁴ or less at 60 ° C. or more and a dielectric constant of 8 or more and 60 to 77 GHz.