JPS5849971B2 - Sankabutsuyudenzairiyou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to La, A7. The present invention relates to a temperature-compensating oxide dielectric material composed of a portion of Ti and having a temperature coefficient of dielectric constant in the range of 1480 to +300'Cpprn/°C.

The object of the present invention is to provide dielectric loss tsn when dielectric constant ε is 30 or more.
It is an object of the present invention to provide a set FEW suitable for microwave dielectric materials and capacitor materials in which δ is small and the dielectric constant temperature coefficient (denoted as εT-) can be controlled to any positive or negative value.

In the microwave region, dielectric materials have been conventionally applied to impedance matching of microwave circuits, dielectric resonators, etc.7)).

In particular, with the recent increase in the number of communication networks, the frequency range used has expanded to the low range, sub-millimeter wave, and □ wave range, and along with the demand for microwave ICs, the technology has advanced, stabilizing the oscillator frequency and controlling the delay time. , and miniaturization of IC substrates for microwave circuits using high dielectric constant and low loss dielectric materials is being actively pursued.

BaO--TiO2-based materials are known as conventional general dielectric materials, but they exhibit a large negative temperature coefficient of dielectric constant and cannot be obtained with positive εT-.

In addition, aluminum sintered body 'PMg T io 3, Ca
Although a positive εT-K can be obtained with the T i03 system, it has the drawback of a low dielectric constant.

The present invention eliminates these drawbacks and newly introduces La
2 o3j At203 t In a dielectric composition composed of T 102 (・te(La1-XAtX)203
.

It was discovered that a composition of 2yTiO2 can be synthesized as an excellent microwave dielectric material and capacitor material.

Here, the present invention is (Lat x Atx) 203 .

In the composition coated with 2yTi02, the value of X is 0.1≦X≦o, 9. It is characterized in that the value of y is within a composition range satisfying 0.3≦y≦2.0.

The sample has a composition of (LaI-XAtx)203-2yTi02, and the raw materials of La2o3j A403)T102 are weighed according to each composition, mixed in a bowl, and heated to 1000°C = 4.
It was obtained by calcining at 1,380° C. to 1,450° C. in air for 2 hours after compression molding.

After that, the dielectric constant was measured at room temperature at 9 GHz, and the temperature coefficient was
Measured at MHz.

Examples will be explained below.

(La1-XAtX)X with the composition of 203.2yTiO2
Table 1 shows each characteristic when the value of and the value of y are changed.

As shown in Table 1, when changing the La/At O ratio,
As A7, that is, the value of
It shows small values of 1 to +16 ppm/'C.

Further, as the value of X increases, εT-K changes from positive to negative, and the value tends to increase.

By appropriately selecting the value of X in this way, any εT
, K.

If x) is 0.9, the dielectric loss will be large and the firing temperature will be high, making it practically difficult and uneconomical.

Further, when the value of y is y<0.3, εT and K become positively large, and the dielectric loss also becomes large.

y)2. . In this case, εT,K becomes large and negative, making it difficult to put it into practical use.

As described above, the composition of the present invention has a dielectric constant of 30 or more, a small dielectric loss, and a small temperature coefficient of the dielectric constant.
It is also clear that it is an excellent material that can obtain any positive or negative value.

It is clear that these materials are extremely useful as dielectric materials having a large dielectric constant and a small temperature coefficient of permittivity in the microwave, quasi-wave, etc. regions.

It was confirmed that this material has low dielectric loss even in the low frequency range, and is an excellent material for temperature-compensating ceramic capacitors in which the value of the temperature coefficient of permittivity can be arbitrarily selected.

Claims (1)

[Claims] 1 (LaI-XAtX)203.2yT102, the value of X is 0.1≦X≦0.
An oxide dielectric material characterized by having a composition in which the value of 9°y satisfies the condition of 0.3≦y≦2.0.