JPH10297960A - Low temperature fired porcelain composition and method for producing low temperature fired porcelain - Google Patents

Abstract

(57) Abstract: A low-temperature fired porcelain composition that can be fired at 800 to 1000 ° C. and has a low dielectric constant, a low dielectric loss tangent, and easy control of a coefficient of thermal expansion in a high-frequency region of 1 GHz or more. And a method for producing low-temperature fired porcelain. SOLUTION: 14.9 to 95% by weight of SiO ₂ and Zn
O and a 1 to 84.9% by weight, the B ₂ O ₃ consisting of 0.1 to 15 wt% and Li ₂ O from 0.1 to 10 wt%, or the SiO ₂ 14.9-95 wt %, the ZnO from 1 to 84.5% by weight, the Li ₂ O 0.1 to 10 wt%
And a glass containing at least SiO ₂ and B ₂ O ₃ at 0.5 to 20% by weight.
800 ° C to 1000 ° C in an oxidizing or non-oxidizing atmosphere
And a crystal phase containing at least ZnO and SiO ₂ and a SiO ₂ phase as a main phase, and further as a sub phase,
It contains a crystal phase containing at least SiO ₂ , Li ₂ O and ZnO, has a dielectric constant (εr) of 7 or less at 1 GHz to 60 GHz, a dielectric loss of 30 × 10 ⁻⁴ or less, and a thermal expansion coefficient from room temperature to 400 ° C. A porcelain having characteristics of 2 to 17 ppm / ° C. is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-temperature fired porcelain composition useful as an insulating substrate in a multilayer circuit board and a method for producing a low-temperature fired porcelain. For example, an integrated circuit (IC) or an electronic component is formed into a multilayer. The present invention relates to a low-temperature fired porcelain composition having a low dielectric constant and a low dielectric loss, particularly for high frequencies, which can be laminated and fired for copper wiring, and to an improvement in a method of manufacturing the low-temperature fired porcelain.

[0002]

2. Description of the Related Art Conventionally, as a ceramic wiring board,
Alumina wiring boards made of ceramics such as alumina are widely used as the insulating substrate. High alumina substrate (3
The relative dielectric constant of 9 to 9.5 at GHz is not suitable for a high-frequency circuit board or the like. That is, in order to propagate a signal at a high speed, an insulating substrate material is required to have a lower dielectric constant. In addition, low loss is required for microwave and millimeter wave applications.

Therefore, as a ceramic material that can cope with the above-mentioned low dielectric constant, for example, a so-called glass ceramic formed by molding and firing a mixture of glass and an inorganic filler has a dielectric constant of about 3 to 7. From low
It is attracting attention as a high-frequency insulating substrate. In addition, since this glass ceramic can be fired at a low temperature of 800 to 1000 ° C., copper,
It has the advantage that low resistance metals such as gold and silver can be used.

On the other hand, when mounting various electronic components on a multilayer wiring board, attaching input / output terminals and the like, and connecting the multilayer wiring board to a printed circuit board such as a motherboard, these electronic components and input / output terminals are used. In order to prevent the substrate from being broken or chipped due to the stress applied to the substrate due to the difference in the coefficient of thermal expansion from the printed circuit board or the like, it is desired that the thermal expansion coefficients between the respective materials be similar. .

[0005]

However, although the conventional glass ceramic material has a low dielectric constant, its dielectric loss is as high as 20 × 10 ^-4 or more with respect to a microwave having a signal frequency of 10 GHz or more. Such a high-frequency device does not have characteristics sufficient for practical use.

Moreover, in conventional glass ceramics, it is difficult to variously adjust the coefficient of thermal expansion even if the composition is adjusted only with the components that determine the dielectric properties. Required, and as a result, there is a problem that the dielectric properties are impaired.

Accordingly, the present invention can be co-fired with a low-resistance metal such as copper, gold, and silver, has a low dielectric constant and a low dielectric loss tangent in a high-frequency range, and exhibits a linear thermal expansion behavior. Further, it is an object of the present invention to provide a low-temperature fired porcelain composition and a method of manufacturing a low-temperature fired porcelain whose thermal expansion coefficient can be adjusted between 2 and 17 ppm / ° C.

[0008]

Means for Solving the Problems As a result of diligent studies of the above problems, the present inventors have found that a composite oxide containing Zn and Si at a specific ratio can be used with Li ₂ O, B ₂ O ₃ or at least. By adding a glass containing SiO ₂ and B ₂ O ₃ , a liquid phase reaction due to ZnO in the composite oxide and a B (boron) component in B ₂ O ₃ , and further a Li in Li ₂ O
Slight B due to addition of liquid phase reaction due to components
_{With 2} O ₃ and Li ₂ O, it can be fired at a temperature of 800 to 1000 ° C. or less, and by firing, as a crystal phase,
It has been found that by precipitating a willemite crystal phase or a SiO ₂ crystal phase containing at least Zn and Si, a low relative dielectric constant and a low dielectric loss tangent, and furthermore, a coefficient of thermal expansion can be widely adjusted between 2 and 17 ppm / ° C. This has led to the present invention.

That is, the low-temperature fired porcelain composition of the present invention comprises S
the iO ₂ and 14.9 to 95% by weight, the ZnO 1~84.
9 wt% and the B ₂ O ₃ 0.1 to 15% by weight and Li
0.1 to 10% by weight of ₂ O or SiO
₂ 14.9 to 95 wt%, the ZnO 1 to 84.5% by weight, and 0.1 to 10 wt% of Li ₂ O, at least Si
Glass 0.5 to 20 wt% containing O ₂ and B ₂ O _3, is characterized in that consists of capital.

Further, such a porcelain composition has a crystal phase containing at least ZnO and SiO ₂ as a main phase by firing, and at least SiO ₂ and Li as sub phases.
A crystal phase containing ₂ O and ZnO and a porcelain containing SiO ₂ crystal phase can be obtained. The dielectric constant (εr) at 1 GHz to 60 GHz is 7 or less, the dielectric loss is 30 × 10 ⁻⁴ or less,
Further, the coefficient of thermal expansion from room temperature to 400 ° C. is 2 to 17
It has a characteristic of ppm / ° C.

Further, in the method for producing a low-temperature fired porcelain of the present invention, each of the above-mentioned compositions is molded into a predetermined shape and then fired at 800 to 1000 ° C. in an oxidizing or non-oxidizing atmosphere. Is manufactured.

[0012]

According to a first aspect of the low temperature sintering ceramic composition of the embodiment of the present invention, the SiO ₂ 14.9-95 wt%
1 to 84.9% by weight of ZnO and 0.1% by weight of B ₂ O ₃ .
15% by weight and Li ₂ O and is made of 0.1 to 10 wt%.

The reason for limiting each component composition to the above range is as follows.
If SiO ₂ is less than 14.9% by weight, ZnO is excessively precipitated and dielectric loss is deteriorated. If SiO ₂ is more than 95% by weight, sinterability is deteriorated and densification is performed at a low temperature of 1000 ° C. or less. This is because they do not. Desired amount of SiO ₂ is 25 to 90 wt%.

On the other hand, if the content of ZnO is less than 1% by weight, a sufficient liquid phase is not formed, and densification is not performed at a low temperature of 1000 ° C. or less. If the content is more than 84.9% by weight, ZnO is excessively precipitated. This causes the dielectric loss to deteriorate. The preferred amount of ZnO is 10-60% by weight.

Further, when the content of Li ₂ O is less than 0.1% by weight, when the amount of SiO ₂ is large, the main phase S
This is because the iO ₂ phase easily transforms into cristobalite and exhibits a thermal expansion behavior having an inflection point near 200 ° C., and if it exceeds 10% by weight, the dielectric loss is deteriorated. is there. A desirable range of Li ₂ O is
1 to 5% by weight.

If the amount of B ₂ O ₃ is less than 0.1% by weight, the porcelain cannot be sufficiently densified at a temperature of 800 to 1000 ° C. Is generated and the dielectric loss tangent in the high frequency range of 1 to 60 GHz exceeds 30 × 10 ⁻⁴ . Preferred range of B ₂ O ₃ is 1 to 5 wt%.

According to a second aspect of the present invention, the Si
14.9 to 95% by weight of O _{2, 1} to 84.5% by weight of ZnO, 0.1 to 10% by weight of Li ₂ O, and at least S
iO ₂ and B ₂ O ₃ glass 0.5 to 20% by weight containing consists.

In this composition, SiO ₂ , ZnO,
The reason for limiting the amount of Li ₂ O is the same as in the first embodiment. If the glass content of the glass containing at least SiO ₂ and B ₂ O ₃ is less than 0.5% by weight, the porcelain cannot be sufficiently densified at a temperature of 800 to 1000 ° C. If the amount is too large, an excessive liquid phase is generated, and the dielectric loss tangent in the high frequency range of 1 to 60 GHz is higher than 30 × 10 ⁻⁴ . A desirable range of the glass containing at least SiO ₂ and B ₂ O ₃ is 1 to 10% by weight.

It should be noted that at least the above-mentioned SiO ₂ , B ₂ O
_As glass containing ₃ , generally, borosilicate glass,
Zinc borosilicate glass, although borosilicate lead glass is preferably used, in particular a SiO ₂ 5 to 80 wt%,
Wherein each B ₂ O ₃ in a proportion of 4-50 wt%, the Al ₂ O ₃ 30 wt% or less as another component, are preferably used those containing alkali metal oxides in a proportion of 20 wt% or less, A mixture of these oxide components in a predetermined ratio is melted, cooled, and vitrified.

Further, the porcelain compositions of the first and second embodiments can be densified to a relative density of 95% or more by firing in a temperature range of 800 to 1000 ° C., and thus formed. The porcelain is shown in FIGS.
As shown in the schematic diagram of the porcelain structure of the above, as a crystal phase, a crystal phase (W) containing at least ZnO and SiO ₂ or a SiO ₂ (quartz) crystal phase (Q) is used as a main phase, and at least SiO 2 is used as a sub phase. ₂ , Li ₂ O and Zn
In some cases, an amorphous phase containing SiO _2, ZnO, or B ₂ O ₃ may be precipitated, including a crystalline phase (L) containing O.

The crystal phase containing at least ZnO and SiO ₂ is willemite (Zn ₂ SiO _2).
Type ₄ ) crystalline phase. Further, at least SiO ₂ , Li
_The crystal phase containing ₂ O and ZnO is Zn, in which Zn and Li form a solid solution at the Si site of the Zn ₂ SiO ₄ type crystal.
₂ (Znx Liy Siz) O ₄ (x + y + z = 1) crystal phase and / or Li ₂ ZnSiO ₄ type crystal.
Further, the SiO ₂ phase includes a quartz phase, and a small amount of a crystal phase such as a cristobalite phase and a tridymite phase may be precipitated in some cases.

As described above, according to the present invention, a crystal phase containing at least Zn and Si, a SiO ₂ -based crystal phase, and the like can be precipitated in a porcelain. As a result, a low dielectric constant of 7 or less is obtained. In addition, it has a low loss characteristic of a dielectric loss of 30 × 10 ⁻⁴ or less in a high frequency band such as a microwave and a millimeter wave, specifically, in a range of 1 GHz to 60 GHz. Moreover, by controlling the composition of the composition in the above-described range, the porcelain has a coefficient of thermal expansion in a temperature range from room temperature to 400 ° C. due to fluctuations in the ratio of crystal phases while maintaining the above-mentioned dielectric properties. 2 to 17 ppm /
It can be controlled in the range of ° C. and shows a linear thermal expansion behavior.

Further, according to the method for producing a low-temperature fired porcelain of the present invention, in obtaining the above-mentioned composition, a raw material powder represented by Zn ₂ SiO ₄
Crystalline or amorphous SiO ₂ is preferably used.

The source of B ₂ O ₃ is B ₂ O ₃ , and B ₂ S ₃ and H ₂ BO which can form B ₂ O ₃ in the sintering process.
₃ and at least one is used from the group of compounds such as zinc borate, such as _{ZnO · 2B 2 O 3, 4ZnO} · 3B 2 O 3.

Furthermore, Li ₂ O as source, Li ₂ O, during sintering L ₂ O capable of forming Li ₂ CO _3, LiOH
・ H ₂ O, Li ₂ S, etc., or Li ₂ SiO ₃ , Li
₄ SiO ₄ , Li ₂ Si ₂ O ₅ , Li ₂ Si ₃ O ₇ , L
Compounds containing SiO ₂ and Li ₂ O, such as i ₆ Si ₂ O ₇ and Li ₈ SiO ₆ , Li ₂ ZnSiO ₄ , Zn
_At least one selected from the group of compounds containing SiO ₂ , Li ₂ O, and ZnO, such as ₂ (ZnxLiySiz) O ₄ (x + y + z = 1), is used.

Still further, at least SiO ₂ and B
_As the glass containing ₂ O ₃ , borosilicate-based glass, zinc borosilicate-based glass, lead borosilicate-based glass, and the like are preferably used as described above.

Using these raw materials, the composition of the first embodiment or the second embodiment is prepared and mixed. Then, after appropriately adding a binder to the mixed powder, for example, after being formed into an arbitrary shape by a die press, a cold isostatic press, an extrusion molding, a doctor blade method, a rolling method, or the like, in an oxidizing atmosphere or N 2 ₂ , 800 ° C. to 1000 ° C., particularly 900 to 10 ° C. in a non-oxidizing atmosphere such as Ar
By baking at a temperature of 00 ° C. for 0.1 to 5 hours, it is possible to densify to a relative density of 95% or more.

If the firing temperature at this time is lower than 800 ° C.,
The porcelain is not sufficiently densified. If the temperature exceeds 1000 ° C., densification is possible, but simultaneous sintering with a conductor such as copper or silver cannot be performed. Incidentally, at the time of simultaneous firing, it is necessary to fire in a non-oxidizing atmosphere when copper is used as the conductor and in a non-oxidizing or oxidizing atmosphere when using silver as the conductor.
This is because a copper conductor cannot be used.

According to the above method of the present invention, Zn and S
i, a composite oxide comprising B ₂ O ₃ or SiO ₂ ,
By further combining Li ₂ O with the glass containing B ₂ O ₃ , the liquid phase mainly composed of Zn generated from the composite oxide and the more active B (boron) component in B ₂ O ₃ or in the glass can be obtained. A liquid phase reaction occurs. Further, Li in Li ₂ O
A small amount of B ₂ O ₃ ,
Li ₂ O can be fired at a temperature of 800 to 1000 ° C. or less, and the porcelain can be densified. For this reason, the amount of the amorphous phase at the grain boundary, which causes an increase in the dielectric loss tangent, can be minimized. Therefore, a lower dielectric loss tangent can be obtained in a high frequency band.

Further, the porcelain composition according to the present invention comprises:
Since it can be fired at 0 to 1000 ° C., particularly copper,
It can be used as an insulating substrate of a wiring board for wiring gold, silver, and the like. In the case of manufacturing a wiring board using such a porcelain composition, for example, according to a known tape forming method, for example, a doctor blade method, a rolling method, or the like, the mixed powder prepared as described above is used to form an insulating layer forming green. After making the sheet, on the surface of the sheet for the wiring circuit layer,
At least one metal of copper, gold and silver, especially
Using a conductive paste containing copper powder, print the wiring pattern on the surface of the green sheet in a circuit pattern by screen printing, gravure printing, etc. In some cases, fill the above conductive paste after forming through holes and via holes in the sheet I do. After that, a plurality of green sheets are stacked and pressed, and then fired under the above-described conditions, whereby the wiring layer and the insulating layer can be fired simultaneously.

[0031]

【Example】

Example 1 Zn ₂ SiO ₄ and ZnO · 2B having an average particle size of 1 μm or less
Compound represented by ₂ O ₃ , 4ZnO · 3B ₂ O ₃ , Si
O ₂ (amorphous) and Li ₂ O were used as raw materials and mixed according to the composition shown in Table 1. Then, an organic binder, a plasticizer, and toluene were added to the mixture, and a green sheet having a thickness of 300 μm was prepared by a doctor blade method. Then, five green sheets are laminated, and the temperature is set to 50 ° C.
A pressure of 100 kg / cm ² was applied at a temperature of, and thermocompression bonding was performed. The obtained laminate is placed in a nitrogen atmosphere containing water vapor at 70
After removing the binder at 0 ° C., it was fired in dry nitrogen under the conditions shown in Table 1 to obtain a porcelain for a multilayer substrate.

The dielectric constant and the dielectric loss tangent of the obtained sintered body were evaluated by the following methods. The measurement is 1-5m in shape diameter
A sample having a thickness of m and a thickness of 2 to 3 mm was cut out and subjected to a dielectric cylinder resonator method at 60 GHz using a network analyzer and a synthesized sweeper. In the measurement,
The dielectric resonator was excited by the NRD guide (non-radiative dielectric line), and the dielectric constant and the dielectric loss tangent were calculated from the resonance characteristics of the TE021 and TE031 modes. Table 1 shows the measurement results.
It was shown to. The constituent phases of the porcelain were identified from the X-ray diffraction measurement, and the X-ray diffraction charts of Sample Nos. 8 and 15 are shown in FIGS. Further, for each porcelain, the coefficient of thermal expansion in the temperature range from room temperature to 400 ° C. was measured, and the presence or absence of an inflection point near 200 ° C. in the thermal expansion curve within the temperature range was confirmed. The thermal expansion curves of Sample No. 19 and Sample No. 9 are shown in FIGS.

As a comparative example, Zn ₂ SiO ₄ , S
Similarly, sintered bodies were prepared and evaluated using MgSiO ₃ and CaSiO ₃ instead of iO ₂ (Sample Nos. 25 and 2).
6).

[0034]

[Table 1]

As is clear from the results in Table 1, the crystal phases were willemite crystal phase (Zn ₂ SiO ₄ ), SiO ₂
The porcelain of the present invention in which the _second crystal phase is mainly deposited has a dielectric constant of 7 or less and a dielectric loss tangent of 30 × 1 at 60 GHz.
Excellent values of 0 ^-4 or less were shown.

On the other hand, in Sample No. 1 in which the amount of SiO ₂ exceeds 95% by weight, densification could not be achieved unless the temperature was raised to 1600 ° C., and when it was less than 14.9% by weight, the dielectric properties were significantly deteriorated. In Sample No. 13 in which the amount of B ₂ O ₃ was less than 0.1% by weight, densification was not possible unless the firing temperature was increased to 1300 ° C., which was not suitable for the purpose of the present invention. On the other hand, sample N in which the amount of B ₂ O ₃ exceeds 15% by weight
In No. o.16, the dielectric loss was increased and the dielectric properties could not be evaluated at 60 GHz. In sample No. 9 in which the amount of Li ₂ O was less than 0.1% by weight, a large amount of cristobalite was precipitated, and as a result, an inflection point occurred in the thermal expansion curve. In addition, as a result of analyzing the liquid phase of the porcelain of the present invention by ICP emission spectroscopy, elements of Zn and B were detected in the liquid phase in each case.

Sample N having a ZnO content of more than 84.9% by weight
In the case of o.24, an excessive ZnO phase was precipitated, which increased the dielectric loss, and the dielectric properties could not be evaluated at 60 GHz.

On the other hand, the sample No. having a ZnO content of less than 1% by weight.
In No. 3, an excessive SiO ₂ phase is precipitated, and the Zn content is insufficient, so that it is difficult to form a liquid phase with the B component in B ₂ O ₃ , and densification cannot be achieved unless the temperature is raised to 1400 ° C. Was.

As comparative examples, MgSiO ₃ and Ca
In Samples Nos. 25 and 26 using SiO ₃ , if the amount of B ₂ O ₃ was not more than 15% by weight, densification would not be achieved, and sufficient dielectric properties could not be obtained, which was not suitable for the purpose of the present invention. .

Example 2 A glass powder having the composition shown in Table 2 was mixed with Zn ₂ SiO ₄ , Li ₂ O and SiO ₂ having an average particle diameter of 1 μm or less so as to have the composition shown in Table 3. Then, an organic binder, a plasticizer, and toluene were added to the mixture, and a green sheet having a thickness of 300 μm was prepared by a doctor blade method. Then, five green sheets are laminated, and the temperature is set to 50 ° C.
A pressure of 100 kg / cm ² was applied at a temperature of, and thermocompression bonding was performed. The obtained laminate is placed in a steam-containing / nitrogen atmosphere at 7
After removing the binder at 00 ° C., it was fired in dry nitrogen under the conditions shown in Table 3 to obtain a porcelain for a multilayer substrate.

With respect to the obtained sintered body, the dielectric constant, the dielectric loss tangent, the identification of the crystal phase, and the thermal expansion coefficient were measured and evaluated in the same manner as in Example 1 in the same manner as in Example 1. The results of the measurement are shown in Table 3.

[0042]

[Table 2]

[0043]

[Table 3]

As is clear from the results in Tables 2 and 3, the samples controlled to the composition of the present invention were prepared in the same manner as in Example 1,
Both can be densified at 1000 ° C. or lower, and willemite crystal phase or SiO ₂ -based crystal is mainly precipitated as a crystal phase, and all have an excellent dielectric constant of 7 or less and a dielectric loss tangent at 60 GHz of 30 × 10 ^-4 or less. Value. Moreover, the coefficient of thermal expansion was controllable in the range of 1.5 to 17 ppm / ° C., and there was no inflection point.

Example 3 A cylindrical sample having a diameter of 1 to 30 mm and a thickness of 2 to 15 mm was produced using the porcelains of Nos. 8 and 15 in the above Example 1. For comparison, a cordierite glass ceramic (75% by weight of borosilicate glass, Al ₂ O
₃ 25 wt%), low purity alumina universal (Al ₂ O ₃ 9
5% by weight, 5% by weight of CaO and MgO) to prepare a sample in the same manner. The prepared sample was 1 GHz, 1
In a high frequency range of 0 GHz, 20 GHz, 30 GHz, and 60 GHz, a microwave, and a millimeter wave, the dielectric loss tangent was measured by a dielectric cylinder resonator method. The results are shown in FIG.

The general-purpose glass ceramic has a low dielectric loss tangent of 7 × 10 ⁻⁴ in the low frequency region, but its characteristics deteriorate in the high frequency region.
It will be about 0 × 10 ^-4 . In addition, general-purpose low-purity alumina increased to about 40 × 10 ^{−4 at} 60 GHz. On the other hand, the product of the present invention had a low dielectric loss tangent of 30 × 10 ⁻⁴ or less even in a high frequency region at 60 GHz. The dielectric constant was 5 for general-purpose glass ceramics and 9 for low-purity alumina.

[0047]

As described above in detail, the low-temperature fired porcelain composition of the present invention has a low dielectric constant and a small dielectric loss tangent even at a high frequency of 30 GHz or more. is there. Furthermore, since the coefficient of thermal expansion can be controlled widely by linear thermal expansion behavior without impairing the dielectric properties, wiring boards using such porcelain can be mounted on printed boards such as motherboards, and electronic components and input / output terminals can be used. At the time of mounting, the difference in thermal expansion can be reduced, so that a highly reliable substrate can be manufactured. In addition, since firing is performed at 800 to 1000 ° C., wirings of Cu, Au, Ag, or the like can be formed by simultaneous firing.

[Brief description of the drawings]

FIG. 1 is a schematic view of a structure of a dielectric porcelain of the present invention.

FIG. 2 is an X-ray diffraction chart of a dielectric ceramic (sample No. 8) of the present invention.

FIG. 3 is an X-ray diffraction chart of a dielectric porcelain (sample No. 15) of the present invention.

FIG. 4 is a view showing a thermal expansion curve of a dielectric ceramic (sample No. 19) of the present invention.

FIG. 5 is a view showing a thermal expansion curve of a dielectric ceramic (sample No. 9) of a comparative example.

FIG. 6 is a diagram showing a relationship between a product of the present invention and a conventional product, with respect to a measured frequency of dielectric loss tangent.

Claims (8)

[Claims] (1) SiO ₂ content of 14.9 to 95% by weight, Zn
O and a 1 to 84.9% by weight, low-temperature fired ceramic composition characterized by comprising a B ₂ O ₃ and 0.1 to 15 wt% and Li ₂ O from 0.1 to 10 wt%. 2. The method of claim 2, wherein at least ZnO and S
a crystal phase comprising iO ₂ as the main phase, further a subphase, at least a crystalline phase comprising SiO _2, Li ₂ O and ZnO, according to claim 1, characterized in that porcelain containing SiO ₂ crystal phase is obtained Low temperature firing porcelain composition. 3. The fired porcelain has a dielectric constant (εr) of 7 or less at 1 GHz to 60 GHz, a dielectric loss of 30 × 10 ⁻⁴ or less, and a coefficient of thermal expansion from room temperature to 400 ° C. of 1.
The low-temperature fired porcelain composition according to claim 1, having a characteristic of 5 to 17 ppm / ° C. 4. An amount of 14.9 to 95% by weight of SiO ₂ , ZnO
1 to 84.5% by weight, Li ₂ O 0.1 to 10% by weight
When the low-temperature fired ceramic composition comprising: the glass 0.5 to 20 wt% containing at least SiO ₂ and B ₂ O _3, in that it consists of and. 5. At least ZnO and S
a crystal phase comprising iO ₂ as the main phase, further a subphase, at least a crystalline phase comprising SiO _2, Li ₂ O and ZnO, according to claim 4, characterized in that porcelain containing SiO ₂ crystal phase is obtained Low temperature firing porcelain composition. 6. The fired porcelain has a dielectric constant (εr) of 7 or less at 1 GHz to 60 GHz, a dielectric loss of 30 × 10 ⁻⁴ or less, and a coefficient of thermal expansion from room temperature to 400 ° C. of 1.
The low-temperature fired porcelain composition according to claim 4, having a characteristic of 5 to 17 ppm / ° C. 7. A willemite compound containing at least ZnO and SiO ₂ and a crystalline and amorphous SiO 2
And _2, B ₂ O _3, and at least one selected from the group consisting of boron compounds and zinc borate compound capable of forming a B ₂ O ₃ during sintering, Li ₂ O, to form a Li ₂ O during sintering Using the obtained lithium compound, a compound containing at least SiO ₂ , Li ₂ O and a compound containing at least SiO ₂ , Li ₂ O and ZnO, 14.9 to 95% by weight of SiO ₂ And ZnO
And 1 to 84.9 wt%, B a ₂ O ₃ to prepare a composition from 0.1 to 10% by weight 0.1 to 15% by weight and Li ₂ O, after molding into a predetermined shape, oxidation or A method for producing a low-temperature fired porcelain, which is fired at 800 to 1000 ° C. in a non-oxidizing atmosphere. 8. A willemite compound containing at least ZnO and SiO ₂ and a crystalline and amorphous SiO 2
At least a _2, Li ₂ O, lithium compound capable of forming a Li ₂ O in the sintering process, selected from the group consisting of at least SiO _2, Li ₂ compounds containing O and at least SiO _2, Li compounds comprising ₂ O and ZnO Using one kind and a glass containing at least SiO ₂ and B ₂ O ₃ , 14.9 to 95% by weight of SiO ₂ and 1 to 8% of ZnO are used.
4.5% by weight, 0.1 to 10% by weight of Li ₂ O, glass 0.5 containing at least SiO ₂ and B ₂ O ₃
From 20 to 20% by weight, and after forming into a predetermined shape, in an oxidizing or non-oxidizing atmosphere, at 800 ° C to 100 ° C.
A method for producing low-temperature fired porcelain, which is fired at 0 ° C.