JPH10130049A - Colored aluminous sintered compact and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a colored aluminous sintered compact having an easily distinguishable blackish color without deteriorating electrical characteristics peculiar to an aluminous sintered compact as the insulating substrate of a multilayer circuit board, package for housing semiconductor device, etc., in a high frequency region. SOLUTION: A compact consisting of 0.05-5wt.% (expressed in terms of oxide) Nb or Nb compd., 0.02-5wt.% (expressed in terms of oxide) at least one among Y, Yb and their compds. and the balance Al2 O3 is fired in a reducing atmosphere to obtain the objective colored aluminous sintered compact consisting of 0.05-5wt.% (expressed in terms of oxide) Nb, 0.02-5wt.% (expressed in terms of oxide) at least one of Y and Yb and the balance Al2 O3 with inevitable impurities.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a colored alumina sintered body suitable for an insulating substrate such as a package for accommodating a semiconductor element, particularly an insulating substrate such as a multilayer wiring board or a package for accommodating a semiconductor element used in a high frequency region. It relates to a manufacturing method.

[0002]

2. Description of the Related Art Conventionally, properties required for ceramic materials include thermal properties such as heat resistance, mechanical properties such as strength, chemical properties such as corrosion resistance, and electromagnetic properties such as conductivity. From such characteristics, Al ₂ O ₃ is used as an insulating substrate in various wiring boards and packages for housing semiconductor elements.
As a main component, and MgO, SiO ₂ , Ca as a sintering aid.
Alumina sintered bodies obtained by adding an appropriate amount of O or the like and sintering have been used in many cases.

In recent years, as the speed of LSIs has increased and the amount of information in the communication field has increased, there has been a demand for a base material having a small loss in a high-frequency region. For such a purpose, a high-purity alumina material has conventionally been used. ing.

[0004] The high-purity alumina material can make use of the excellent electrical characteristics of Al ₂ O _{3 as} it is, because it has few additives. However, since the Al ₂ O ₃ itself is white, high-purity alumina material is used. The sintered body also has a white color.

On the other hand, in electronic parts, parts for semiconductor manufacturing, various measuring devices, etc., colored alumina sintered bodies such as black are required. The reason is that a small amount of dust greatly affects the accuracy and performance of these parts, so in the case of colored sintered bodies, the presence of these dusts can be quickly found, and in the case of wear or damage of parts Has the advantage that the part can be easily identified.

Further, when manufacturing a package for accommodating a semiconductor element or the like, a contrast is necessary in order to optically identify a wire bonding position, and a colored alumina sintered body is more colored than a white alumina sintered body. Is more preferred.

As such a colored alumina sintered body, Al ₂ O ₃ has been conventionally used as a main component, and WO ₃ and MoO have been used.
_A molded article made of a raw material to which a pigment such as
It was colored by firing at a temperature of at least ℃.

[0008]

However, in a conventional colored alumina-based sintered body, WO ₃ or Mo is used as a coloring agent.
Addition of a pigment such as O ₃ may cause a decrease in electrical properties and high-temperature physical properties, that is, a decrease in mechanical properties. In particular, in a high frequency region of 1 GHz or higher, dielectric loss increases. There has been a problem that the electrical, mechanical, and thermal characteristics peculiar to the sintered body are impaired.

[0009]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an original alumina-based sintered body as an insulating base for a multilayer wiring board or a package for housing semiconductor elements in a high-frequency region. An object of the present invention is to obtain a colored alumina-based sintered body that does not impair the electrical characteristics and has a blackish color that can be easily identified.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of the above problems and found that Nb or Nb
In the case of an alumina sintered body to which a compound and one or more of Y or a Y compound, Yb, and a Yb compound are added, a blackish color that can be easily identified is obtained, and the dielectric loss in a high frequency region is determined by the dielectric loss of the alumina body. In addition, the inventors have found that it is possible to improve the mechanical properties as compared with the conventional high-purity alumina-based sintered body, and have reached the present invention.

That is, the colored alumina sintered body of the present invention comprises:
And 0.05 to 5% by weight in terms of oxide and nb, Y, in a proportion of the total amount 0.02 to 5% by weight in terms of oxide of at least one of Yb, balance Al ₂ O ₃ and inevitable And Nb or an Nb compound in the form of an oxide in the range of 0.05 to 5 in terms of oxide.
%, And a compact containing at least one of Y, Yb, the Y compound, and the Yb compound in a proportion of 0.02 to 5% by weight in terms of oxide and a balance of Al ₂ O ₃ is reduced. It is characterized by firing at a temperature of 1200 to 1700 ° C. in a neutral atmosphere, preferably in an atmosphere containing at least hydrogen.

[0012]

SUMMARY OF colored alumina sintered body and its manufacturing method of the present invention, SiO _2, C conventionally used as a sintering agent
It is a high-purity alumina sintered body to which aO, MgO, etc. are not added, and Nb or an Nb compound is added as a coloring component in an amount of 0.05 to 5% by weight in terms of oxide, and Y, Yb,
By adding and containing at least one of the Y compound and the Yb compound in a total amount of 0.02 to 5% by weight in terms of oxide, dielectric loss can be reduced in a high frequency region as compared with a conventional high-purity alumina sintered body. Thus, the strength can be increased, and at the same time, the color can be colored in an identifiable color.

Thus, it can be effectively used as a wiring board used in a high-frequency region of 1 GHz or more, a package for accommodating a semiconductor element such as a high-speed processing LSI, and an insulating base of various high-frequency circuit boards.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The alumina-based sintered body of the present invention
0.05 to 5% by weight of b or Nb compound in terms of oxide;
In particular, 0.1 to 2% by weight and a total amount of at least one of Y, Yb, Y compound and Yb compound in terms of oxide of 0.02%
-5% by weight, especially 0.05-2% by weight,
The balance consists of Al ₂ O ₃ and unavoidable impurities.

Here, when the content of Nb or Nb compound is less than 0.05% by weight in terms of oxide, the black coloring effect or the effect of reducing the dielectric loss is small, and when it exceeds 5% by weight, the dielectric loss is reduced. From the viewpoint of reducing the dielectric loss, and more preferably 0.1 to 2% by weight.

The total content of at least one of Y, Yb, the Y compound, and the Yb compound is 0.1% in terms of oxide.
When the amount is less than 02% by weight, the effect of reducing the dielectric loss is small, and when it exceeds 5% by weight, the sinterability of the alumina-based sintered body is deteriorated, the dielectric loss is increased, and the mechanical properties are also reduced.

Therefore, the total amount is specified to be 0.02 to 5% by weight, and more preferably 0.05 to 2% by weight from the viewpoint of satisfying various characteristics.

Incidentally, MgO, SiO ₂ , CaO, etc., which are generally added as sintering aids to Al ₂ O ₃ , may significantly increase the loss in the high-frequency range, so that the colored alumina of the present invention may be used. The porous sintered body does not substantially contain these sintering aids and the like, and contains N 2, Nb compound, Y, Yb, Y compound, and Yb compound as components other than Al ₂ O ₃ and unavoidable impurities. is there.

The unavoidable impurities referred to herein are unavoidable impurities contained in the starting material or components unavoidably mixed in the production process, and these are desirably 0.2% by weight or less in total. .

Further, Al ₂ O ₃ used as a raw material powder
In order to obtain good high frequency characteristics, the purity must be 9
The average particle diameter is desirably 9.9% or more, and the average particle diameter is desirably 2.0 μm or less in order to enhance sinterability.

In the production of the colored alumina sintered body according to the present invention, Nb or an Nb compound and at least one of Y, Yb, Y compound and Yb compound are added to Al ₂ O ₃ powder as a main component. When the Nb compound is added in a fixed amount, as the Nb compound, in addition to an oxide or an oxide that can be converted into the above-described oxide in a firing step, a carbide, a nitride,
A bromide or the like may be used, and a Y compound, a Yb compound may be a carbide, a nitride, a fluoride, or the like in addition to an oxide.

Next, an organic binder or the like is added to the composition and mixed well, and then the mixture is subjected to desired molding means, for example, a mold pressing method, a cold isostatic pressing method, an extrusion molding method, a doctor blade method or the like. After being formed into an arbitrary shape and desirably heat-treated in an atmosphere containing water vapor to remove the organic binder, it is fired.

The calcination is performed in a reducing atmosphere, 1200 to 1
Baking at a temperature of 700 ° C. for about 0.5 to 24 hours to obtain a high-purity colored alumina sintered body having a relative density of 97% or more and a high density and excellent in discriminating effect. Can be.

[0024]

EXAMPLE An Al ₂ O ₃ powder having a purity of 99.9% and an average particle diameter of 2 μm was used as a raw material powder and N was added as an additive.
b, Nb compound, Y, Yb, Y compound, and Yb compound are weighed so as to have a ratio as shown in Table 1, mixed by a ball mill, dried and granulated, and press-molded at a pressure of 1000 kg / cm ^2. Then, firing was performed under the conditions shown in Table 1.

An alumina sintered body manufactured using conventional WO ₃ or MoO ₃ as Al ₂ O ₃ alone and as an additive was used as a comparative example.

[0026]

[Table 1]

The color tone of the obtained sintered body was determined, and a bending test piece was cut out from the sintered body in accordance with JIS standard R1601, and the three-point bending strength was measured. The density was calculated.

Each sample was 15 mm in diameter and 7.5 in thickness.
The dielectric constant and dielectric loss tangent were measured under the TE011 mode resonance characteristic conditions when the measurement frequency was 8.5 GHz by the dielectric resonance method, and the dielectric constant was measured. And the dielectric loss was evaluated.

[0029]

[Table 2]

As is clear from the results in the table, the sample No. 1 of the comparative example was white and had voids, had a large dielectric loss of 15 × 10 ^-4 and a low bending strength of 300 MPa. Also, the conventional colored alumina-based sintered bodies of Sample Nos. 2 and _{3 in} which WO ₃ and MoO ₃ were added as a sintering aid and a coloring agent had a large dielectric loss.

In Samples Nos. 4 and 9 in which the Nb component is outside the scope of the present invention in terms of oxide, the dielectric loss is large in both cases. Sample numbers 10, 17, and 18 that are out of the range of
In each case, the sintering becomes insufficient, the strength of the porcelain decreases, and the dielectric loss is large.

On the other hand, by incorporating an Nb component as a colorant according to the present invention and further incorporating a Y or Yb component therein, a distinguishable color can be obtained, the porcelain strength can be improved, and the dielectric loss can be improved. Results were also greatly reduced.

[0033]

As described in detail above, the colored alumina-based sintered body and the method of manufacturing the same according to the present invention can reduce the dielectric loss and increase the strength in the high-frequency region as compared with the conventional high-purity alumina-based sintered body. And at the same time, a color tone excellent in black discrimination effect can be obtained. In particular, a wiring board used in a high-frequency region of 1 GHz or more, a semiconductor device housing package for a high-speed processing LSI, and various circuit boards for a high frequency, etc. It can be effectively used as an insulating substrate.

Claims (2)

[Claims] 1. Nb is 0.05 to 5% by weight in terms of oxide.
And at least one of Y and Yb in a total amount of 0.02 to 5% by weight in terms of oxides, with the balance being Al ₂ O ₃
A colored alumina-based sintered body, comprising: 2. Nb or Nb compound is converted to oxide in 0.0
A molded body containing 5 to 5% by weight and at least one of Y, Yb, a Y compound, and a Yb compound in a proportion of 0.02 to 5% by weight in terms of oxide, and the balance being Al ₂ O ₃ Sintering in a reducing atmosphere.