JPH11349380A - Piezoelectric ceramic composition and piezoelectric element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve heat resistance to heat treatment for a short time, to better heat drift characteristics, to mass produce piezoelectric elements and to stabilize their qualities by mixing a main component composed of a compound oxide of Pb, Ti and Zr with one or more metal elements of Y, Dy, Er, Ho, Tm, Lu and Yb as a subsidiary component and Mn. SOLUTION: A compound oxide contained in a composition is shown by the formula: (1-x)Pb(M1/3 Nb2/3 )a Zrb Tic O3 -xRMnd O1+2d ((x) is a number satisfying 0<x<=0.1; (a) to (c) are numbers satisfying 0<=a<=0.1, 0<=b<=0.7, 0.3<=c<=1.0 and a+b+c=1; (d) is a number satisfying 0.5<=d<=3; M is one or more metal elements of Zn, Ni and Mg; R is one or more metal elements of Y, Dy, Er, Ho, Tm, Lu and Yb).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric ceramic composition used for a ceramic filter, a ceramic oscillator, a piezoelectric transformer, various ceramic sensors, a ceramic buzzer, and the like, and a piezoelectric ceramic having a piezoelectric element and a capacitor element at the same time. The present invention relates to a piezoelectric element such as an oscillator and a piezoelectric ceramic filter.

[0002]

2. Description of the Related Art Conventionally, PbT has been used as a piezoelectric ceramic material.
The so-called PT ceramics containing iO ₃ as a main component,
So-called PZT containing Pb (Ti, Zr) O ₃ as a main component
System ceramics or various complex perovskite compositions, for example, _{Pb (Mg 1/3 Nb 2/3} ) O 3, Pb (Ni 1/3 N
b _2/3 ) Multi-component piezoelectric ceramic compositions in which several types of O _{3 and the} like are dissolved in solid form have been used. In these compositions, by selecting the composition ratio of the components, it is possible to obtain piezoelectric ceramics having various characteristics according to the application. For example, Pb (Zn _1/3 Nb _2/3 )
_A (Sn _1/3 Nb _2/3 ) _B Ti _C Zr _D O ₃ composition (Japanese Patent Publication No.
2-17239, JP-described in _{JP-B-51-7318), Pb (Sn a Sb} 1-a) x Ti y Zr z O 3 based compositions (JP-B 54-32516, JP-Sho 54-367
No. 57) has characteristics such as excellent piezoelectricity and small crystal grain size, and is suitable for a high-frequency ceramic oscillator or filter. Therefore, these piezoelectric ceramic compositions are used for ceramic filters, ceramic oscillators, piezoelectric transformers, ceramic sensors and the like.

When such a piezoelectric ceramic is used after being heated to a temperature of about 250 ° C. and then returned to room temperature for solder reflow, for example, the piezoelectric characteristics such as the resonance frequency of the piezoelectric ceramic change before and after the heat treatment. This was a problem.

This is because the conventional piezoelectric ceramic composition has poor heat resistance of piezoelectric properties such as mechanical quality factor (Q _m ), electromechanical coupling factor (k _t ) and relative permittivity (ε / ε ₀ ). This is because a thermal drift occurs. When a filter is manufactured using such piezoelectric ceramics due to the change, a filter characteristic waveform may be changed due to a thermal shock change. As a countermeasure against this, Japanese Patent Application Laid-Open No. 8-239
No. 269 and Japanese Patent Application Laid-Open No. 9-142930, a composite oxide such as Y or Nb is added to PZT as a main component, or an additive such as Cr is added to PZT.
A countermeasure for reducing the resistance of the piezoelectric ceramic to a material that does not cause a problem with heat resistance is disclosed.

[0005]

As described above, as electronic components such as ceramic filters and ceramic oscillators are formed into chips, the temperature of the chip element at the time of solder mounting is increased, and the temperature of the element is increased to 200. Up to about ° C. When a piezoelectric element made of a conventional piezoelectric ceramic composition is subjected to heat treatment at 150 ° C. for 1 hour, the amount of change in the resonance frequency fr immediately after the treatment reaches several percent, and after that, it changes to a value different from the characteristic value before the treatment while changing over time. Drift. That is, since the conventional piezoelectric ceramic composition has poor heat resistance and changes in characteristics due to thermal drift, it has low reliability and has a problem in a mass production process.

Accordingly, the present invention improves mass productivity and quality stability by improving heat resistance and heat drift characteristics of a PZT-based piezoelectric ceramic material against a short-time heat treatment at about 250 ° C. The purpose is to make 2
A piezoelectric ceramic composition using a piezoelectric ceramic composition having a small change in piezoelectric characteristics before and after returning to room temperature in response to a short-time thermal change of about 50 ° C. and a piezoelectric ceramic composition having excellent heat resistance. With the goal. In particular, it is an object of the present invention to provide a piezoelectric element using a piezoelectric ceramic composition strictly controlled in composition so that the change in capacitance is extremely small in accordance with the small change in resonance frequency.

[0007]

In order to solve the above-mentioned problems, the piezoelectric ceramic composition of the present invention comprises Pb, Ti and Zr.
And Y and D as subcomponents
It is characterized by containing at least one metal element selected from the group consisting of y, Er, Ho, Tm, Lu and Yb, and Mn.

Further, another constitution of the piezoelectric ceramic composition of the present invention is characterized in that the piezoelectric ceramic composition contains a composite oxide represented by the following general formula (I) as a main component.

[0009] (1-x) Pb (M 1/3 Nb 2/3) a Zr b Ti c O 3 -xRMn d O 1 + 2d (I)

(Where x is a number satisfying 0 <x ≦ 0.1, a to c are 0 ≦ a ≦ 0.1, 0 ≦ b ≦ 0.7, 0.3
≦ c ≦ 1.0, a number satisfying a + b + c = 1, and d is 0.
Is a number satisfying 5 ≦ d ≦ 3, and M is Zn, Ni and M
at least one metal element selected from the group consisting of
R is at least one metal element selected from the group consisting of Y, Dy, Er, Ho, Tm, Lu and Yb)

Another composition of the piezoelectric ceramic composition of the present invention is mainly composed of a composite oxide containing Pb and Ti, and further includes a metal element R (where the metal element R is Y, Dy, Er,
And at least one element selected from Ho, Tm, Lu and Yb) and Mn, in terms of an oxide represented by RMnO ₃ , based on the total amount of this oxide and the composite oxide. Is contained at a ratio of 1 to 10 mol%.

By containing the metal elements R and Mn in this way, the piezoelectric oxide has a piezoelectric ceramic composition in which the change in piezoelectric characteristics due to heat treatment is small, and in particular, the change in piezoelectric characteristics with time is reduced. Things.
If the content of the metal elements R and Mn is less than 1 mol%, the effect of adding the metal elements R and Mn cannot be sufficiently obtained. On the other hand, when the content is more than 10 mol%, there is a possibility that the piezoelectric properties of the composition may not be sufficiently obtained.

Further, another constitution of the piezoelectric ceramic composition of the present invention is characterized in that a main component is a composite oxide represented by the following general formula (II).

[0014] (1-x) Pb (M 1/3 Nb 2/3) a Zr b Ti c O 3 -xRMnO 3 (II)

(Where x is a number satisfying 0.01 ≦ x ≦ 0.1, a to c are 0 ≦ a ≦ 0.1, 0 ≦ b ≦ 0.7,
0.3 ≦ c ≦ 1.0, a + b + c = 1, M is at least one metal element selected from the group consisting of Zn, Ni and Mg, and R is Y, Dy, Er, Ho,
At least one metal element selected from the group consisting of Tm, Lu and Yb)

Further, another structure of the piezoelectric ceramic composition of the present invention is as follows: a main component represented by the following general formula (III) and a metal element R (where R is Y, Dy, Er, Ho, T
at least one selected from the group consisting of m, Lu and Yb
Is converted to R ₂ O ₃ to obtain 1 mo
1 to 0.01 mol, and Mn is converted to Mn ₂ O ₃ at a ratio of 0.01 to 0.05 mol per 1 mol of the main component. .

[0017] _{Pb (A, Nb) x Zr} y Ti 1-xy O 3 (III)

(Where x and y are 0 ≦ x ≦ 0.05, 0.
35 ≦ y ≦ 0.80, where A is Sn, Z
at least one selected from the group consisting of n, Ni and Mg
Kind of metal element)

Further, another constitution of the piezoelectric ceramic composition of the present invention is characterized by being represented by the following general formula (IV).

[0020] _{Pb (Y (1-x)} / 2 Mn x / 2 Nb 1/2) a (M 1/3 Nb 2/3) b Zr c Ti d O 3 (IV)

(Where x is a number satisfying 0 ≦ x <1.0, ad is 0.01 ≦ a ≦ 0.15, 0 ≦ b <0.
2, 0 ≦ c ≦ 0.68, 0.3 ≦ d ≦ 0.93, a + b
+ C + d = 1, and M is at least one metal element selected from the group consisting of Zn, Ni and Mg.)

In the piezoelectric ceramic composition, at least one metal element selected from the group consisting of Fe, Cr, Co, Cu, and Sn is further added to an oxide of the metal element, Fe ₂ O ₃ , Cr ₂ O ₃ , CoO, CuO and S
It is preferable to contain it at a ratio of 0.01 to 1.3% by weight in terms of nO ₂ .

Further, the method for producing the piezoelectric ceramic composition of the present invention is characterized in that the pre-calcined main component composed of a composite oxide of Pb, Ti and Zr is added to the pre-calcined RMnO ₃ (where R Is Y, Dy, Er, Ho, T
m, Lu and Yb are added, mixed, and then fired.

Also, a method for producing the piezoelectric ceramic composition of the present invention.
Another structure of the following general formula (III) calcined in advance
And the pre-calcined RMnO
_Three(Where R is Y, Dy, Er, Ho, Tm, Lu and
Yb is one kind of metal element selected from the group consisting of Yb)
The sub-component represented by
R _TwoO_ThreeConverted to 0.01 to 0.05 mol, Mn_TwoO_Three
0.01 to 0.05 mol respectively
Thereafter, firing is performed.

[0025] _{Pb (A, Nb) x Zr} y Ti 1-xy O 3 (III)

(Where x and y are 0 ≦ x ≦ 0.05, 0.
35 ≦ y ≦ 0.80, where A is Sn, Z
at least one selected from the group consisting of n, Ni and Mg
Kind of metal element)

Further, the piezoelectric element of the present invention is characterized by containing the above-mentioned piezoelectric ceramic composition, and is specifically used as a piezoelectric ceramic filter, a piezoelectric ceramic oscillator, various sensors and the like.

Further, a piezoelectric element such as a piezoelectric ceramic oscillator or a piezoelectric ceramic filter having a vibrator portion and a capacitor portion integrally is characterized by using the above piezoelectric ceramic composition.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a piezoelectric ceramic composition and a piezoelectric element of the present invention will be described with reference to embodiments.

Embodiment 1 Raw materials are PbO, Y ₂ O ₃ , MnCO ₃ , TiO ₂ , ZrO ₂
Using a composition formula _{(1-x) PbTi 1-} a Zr a O 3 -xYMn d
O _{1 + 2d} (0 <x ≦ 0.045, 0.529 ≦ a ≦ 0.5
38, 0.5 ≦ d ≦ 3.2), x shown in Table 1
It is weighed at a predetermined ratio so that the composition ratio of the values of a and d is obtained. The obtained raw material powder was mixed using a ball mill,
It calcined at 50-900 degreeC for 2 hours. This raw material powder was pulverized again using a ball mill, and the obtained powder was 13 m in diameter.
It was pressed into a disk-shaped compact having a thickness of 1 mm and a thickness of 1 mm. This was fired at a temperature of 1140 to 1260 ° C. for 2 hours. After the porcelain obtained by firing was polished to a thickness of 0.3 mm, Cr-Au vapor deposition electrodes were formed on both surfaces thereof. This device was placed in a silicone oil at 100 ° C. and applied between both electrodes at 4 kV /
A direct current electric field of 30 mm was applied for 30 minutes to perform polarization processing.
Subsequently, after partially removing the polarization electrode, the structure shown in FIG.
The Cr-Au partial electrode was formed so as to form an energy trap type resonator as shown in FIG. In FIG. 1, 1 is a piezoelectric ceramic, 2 is an electrode, and 3 is a vibrator part (resonator part).

The sample was placed in an oven at 250 ° C. for 10 minutes, and changes in resonance frequency, anti-resonance frequency, and capacitance due to heat treatment were measured by an impedance analyzer. Coefficient, dielectric loss tangent, electromechanical coupling coefficient, and mechanical quality coefficient). Table 1 shows the measurement results.

[0032]

[Table 1]

No. The composition of 1 to 16 is has a value of the coupling coefficient k ₁₅ is large mechanical quality factor (Q _m) is also from 370 to 840, marked with an asterisk in Table 1 No. 17 and 18 have small coupling coefficients and poor characteristics.

A vibrator portion (resonator portion) as shown in FIG.
A Cr-Au electrode was formed so as to be an energy trapping type piezoelectric element having an additional capacitance portion (unpolarized portion) 4 together with 3. This sample was evaluated for temperature characteristics at −20 to 80 ° C., further placed in an oven at 250 ° C. for 10 minutes, and subjected to a heat resistance test to see the change in characteristics before and after heat treatment.
As a result, the frequency stability of the piezoelectric element using the piezoelectric ceramic composition of the present invention is smaller in the amount of change before and after the heat treatment as compared with the conventional piezoelectric material, and a piezoelectric element excellent in heat resistance can be provided. it can.

Embodiment 2 PbO, ZnO, NiO, MgO, Nb ₂
O ₅ , ZrO ₂ , TiO ₂ , Y ₂ O ₃ , Er ₂ O ₃ , Ho
₂ O ₃ , Tm ₂ O ₃ , Lu ₂ O ₃ , Yb ₂ O ₃ , Mn ₃ O ₄ , and Fe ₂ O ₃ , Cr ₂ O ₃ , CoO, CuO, SnO ₂ were used as appropriate, and Table 2 was used. After weighing at a predetermined ratio so as to have each composition ratio shown in Table 4 below, the obtained raw material powders were mixed using a ball mill, and calcined at 750 to 900 ° C. for 2 hours. This raw material powder was pulverized again using a ball mill, and the obtained powder was pressed into a disc-shaped green compact having a diameter of 13 mm and a thickness of 1 mm. This was fired at a temperature of 1140 to 1260 ° C. for 2 hours. The porcelain obtained by firing has a thickness of 0.
After polishing to 3 mm, Cr-Au vapor deposition electrodes were formed on both surfaces. This element was polarized in a silicone oil at 100 ° C. by applying a DC electric field of 5 kV / mm between both electrodes for 30 minutes. Subsequently, after partially removing the polarization electrode, a Cr-Au partial electrode was formed so as to further form an energy trap type resonator.

The sample was placed in an oven at 250 ° C. for 10 minutes, and changes in the resonance frequency, anti-resonance frequency, and capacitance due to the heat treatment were measured using an impedance analyzer. Tables 2 to 4 show the measurement results.

[0037]

[Table 2]

[0038]

[Table 3]

[0039]

[Table 4]

In Tables 2 to 4, the rate of change of fr and the rate of change of capacitance are 24 hours after the heat treatment based on the values of the resonance frequency (fr) and the capacitance (C) after 30 minutes from the heat treatment. The change rates of the resonance frequency (fr) and the capacitance (C) after time are shown, and k ′ is the resonance frequency (fr) and the antiresonance frequency (fa) 24 hours after the heat treatment. Is an apparent coupling coefficient obtained from the relationship of the following formula from the measured values of (i.e., Table 7).

K ′ ² = (fa ² −fr ² ) / fa ²

Sample 1 marked with ** in Table 2 is a conventional piezoelectric ceramic composition containing no metal elements R and Mn. As is clear from Tables 2 to 4, the metal elements R and M
According to the other piezoelectric ceramic compositions containing n, the change rate of the resonance frequency and the change rate of the capacitance could be reduced as compared with Sample 1.

However, in Sample 6 marked with * in Table 2, the content x of YMnO ₃ was relatively large at 0.15,
Although the change rate of the resonance frequency and the change rate of the capacitance are improved as compared with the sample 1, the apparent coupling coefficient k ′ is reduced. As described above, x is a value smaller than 0.15, specifically, preferably 0.01 to 0.1, and more preferably 0.015 to 0.05.

Similarly, sample 11 marked with * in Table 2
Has a relatively large content a of Zn and Nb of 0.15.
In this sample, the change rate of the resonance frequency and the change rate of the capacitance are lower than that of the sample 1, but the degree of improvement is smaller than that of the other samples. As described above, a is preferably a value smaller than 0.15, specifically, 0 to 0.1.

Further, as shown in Table 3, Fe ₂ O ₃ , C
any one of r ₂ O ₃ , CoO, CuO and SnO ₂ is 0.98
When added to PbZr _0.535 Ti _0.465 O ₃ -0.02 YMnO ₃ , the thermal stability could be further improved. In addition,
The amounts (wt%) of these oxides shown in Table 2 indicate the ratio (wt%) to the total composition. Fe, Cr, Co,
Cu and Sn are 0.01 to
It is preferable to add 1.3% by weight, particularly 0.05 to 0.6% by weight.

Further, as shown in Table 4, the heat resistance could be improved even when Zn was replaced with Mg or Ni.
As described above, even when Zn is replaced with a divalent metal element forming a composite perovskite, the same heat stability as that of Zn can be obtained.

As shown in Table 4, Y is
The heat resistance was able to be improved by substitution with Er, Ho, Tm, Lu or Yb. As described above, even when Y is replaced with a trivalent rare earth element, the heat stability is improved. This effect is considered to be due to the fact that Y and the like easily form a manganite compound represented by Mn and RMnO ₃ .

The piezoelectric ceramic composition of the present invention is not limited to the above-described embodiment, and may contain, for example, a trace amount of impurities or additives to such an extent that the object of the present invention is not adversely affected.

Embodiment 3 Using the same oxide as in Embodiment 2 as a raw material,
_{(1-x) PbZr b Ti} c O 3 -xYMnO 3 (0.01 ≦ x ≦
0.1, 0.46 ≦ b ≦ 0.49, 0.51 ≦ c ≦ 0.
54, b + c = 1) represented by weighed so that the composition ratio further Cr ₂ O ₃ the _{(1-x) PbZr b Ti} c O 3 - x
Weighed to be 0.2% by weight based on YMnO ₃ ,
These were mixed in a ball mill and calcined at 850 ° C. for 2 hours. The calcined powder was pulverized again by a ball mill, and the obtained powder was formed into a square plate having a size of 7 × 3 mm and a thickness of 1 mm.
The molded body was fired at a temperature of 1170 ° C. for 2 hours. After firing, the obtained porcelain was polished to a thickness of 0.2 mm, and vapor deposition electrodes made of Cr-Au were formed on both surfaces thereof. The device was placed in a silicone oil at 100 ° C. between both electrodes at 5 kV.
/ Mm DC electric field is applied for 30 minutes to perform polarization processing.
Subsequently, heat treatment was performed at 300 ° C. for 30 minutes. After partially removing the polarizing electrode, the piezoelectric ceramic 1 was made of Cr-Au so as to form an energy trapping type filter as shown in FIG.
The electrode 2 and the additional capacitance section (non-polarized section) 4 were formed so that the vibrator section (resonator section) 3 was formed on the surface of the.

Place this filter in an oven at 250 ° C.
The sample was allowed to stand for 0 minutes, and the change in the filter waveform due to this heat treatment was measured. As a result, the waveform of the piezoelectric ceramic of the present invention using the above-described porcelain composition shows that the change in the filter waveform due to the heat treatment is smaller than that in the case where the conventional composition such as the sample 1 in Table 2 is used. confirmed.

The piezoelectric element of the present invention is not limited to the above-described embodiment, but may be any of various piezoelectric elements formed using a piezoelectric ceramic composition, for example, an oscillator, a resonator, various piezoelectric sensors, A piezoelectric actuator, a piezoelectric transformer, or the like may be used. Further, in order to obtain a large piezoelectric property, although there is no particular limitation, for example, the above (1-x) PbZr _b T
In the range indicated by i _c O ₃ -xYMnO _3, a composition in the vicinity of mono photo b big phase boundary, 0.01 ≦ x ≦
0.03, 0.52 ≦ b ≦ 0.54, 0.46 ≦ c ≦
It is preferably 0.48.

Embodiment 4 Pb is used as a starting material powder._ThreeO_Four, TiO_Two , ZrO_Two , Nb
_TwoO_Five, SnO_Two , ZnO, NiO, MgO, and Mn
CO_Three , Y_TwoO_Three, Dy_TwoO_Three, Er_TwoO_Three, Ho_TwoO_Three, Yb
_TwoO_Three Using Pb_ThreeO_Four, TiO_Two , ZrO_Two , N
b_TwoO_Five, SnO _Two , ZnO, NiO, and MgO are shown in Table 5.
Pb (A, Nb)_xZr_yTi_1-xyO_Three(Where A is S
at least one selected from the group consisting of n, Zn, Ni and Mg
Are one kind of metal element)
Weighed and then MnCO_Three , Y _TwoO_Three, Dy_TwoO_Three, E
r_TwoO_Three, Ho_TwoO_Three, Yb_TwoO_ThreeTo Pb (A, Nb)_xZr_yT
i_{1- xy}O_ThreeRespectively, the oxide Mn
_TwoO_Three, R_TwoO_Three(Where R is Y, Dy, Er, Ho and Y
at least one metal element selected from the group consisting of
) And weigh at a predetermined ratio as shown in Table 5.
After that, these components are mixed with pure water and YTZ cobblestone is used.
For 17 hours. This mixed powder is dried
Calcined at 750-900 ° C.
The resulting powder (flat) was crushed by a ball mill for 15 hours.
13 mm in diameter and 1 m in thickness with a uniform particle size of 1.0 to 1.7 μm)
m to produce a disc-shaped molded body of about 1140-1260
Calcination was carried out at ℃ for 1 hour. After firing, this porcelain is 0.3m thick
After polishing to about m, Cr-Au deposited electrodes on both sides
Was given. After that, a silicon
In the oil, a DC electric field of 3 kV / mm
Polarization was performed by applying for 0 minutes. For this sample, 150
And the resonance frequency (fr) after heat treatment for 30 min.
Measure the resonance frequency (fa) and compare it with the value before heat treatment.
Was. The results are shown in Table 5 for sample numbers 1 to 29.

[0053]

[Table 5]

As is clear from the results in Table 5, the general formula:
_{Pb (A, Nb) x Zr} y Ti 1-xy O 3 ( wherein, x, y is 0
≦ x ≦ 0.05, 0.35 ≦ y ≦ 0.80, and A is at least one metal element selected from the group consisting of Sn, Zn, Ni and Mg). Mn ₂ O ₃ and R ₂ O ₃ as sub-components with respect to the main component (where R is at least one metal element selected from the group consisting of Y, Dy, Er, Ho and Yb) However, the piezoelectric ceramic composition added and mixed at a predetermined ratio, respectively, showed significantly smaller changes in the resonance frequency and anti-resonance frequency after the heat treatment and the subsequent drift amount as compared with the piezoelectric ceramic composition not added. In addition, it was superior to the other samples marked with * in Table 5.

The main component is Pb (Zn _1/6 Sn _1/6 N
b _2/3 ) _0.03 Zr _0.53 Ti _0.41 O ₃
Even in composite oxides composed of more than one kind of metal element A,
Similar effects were obtained.

Embodiment 5 Pb ₃ O ₄ , TiO ₂ , ZrO ₂ , Nb
_{Using 2} O ₅ , SnO ₂ , ZnO, NiO, MgO,
Pb shown in Table _{6 (A, Nb) x Zr} y Ti 1-xy O 3 ( in the formula,
A is at least one metal element selected from the group consisting of Sn, Zn, Ni and Mg), and is weighed so as to have a composition ratio represented by the formula: For 17 hours. Similarly, MnCO ₃ , Y ₂ O ₃ , Dy ₂ O ₃ , Er ₂ O ₃ , Ho
_{Using 2} O ₃ and Yb ₂ O ₃ , RMnO ₃ (where R is Y,
And at least one metal element selected from the group consisting of Dy, Er, Ho, and Yb), and weighed such that pure water was mixed. The mixture was mixed for 17 hours in a ball mill using a cobblestone made by Azuma. Each mixed powder was dried, after calcined separately at 750~900 ℃, Pb (A, Nb ) x Zr y Ti 1-xy O 3
(Where A is at least one metal element selected from the group consisting of Sn, Zn, Ni and Mg), and as a main component, RMnO ₃ as a subcomponent (where R is Y,
Dy, Er, Ho and Yb, which are at least one metal element selected from the group consisting of
The mixture was pulverized for 15 hours with a ball mill using a cobblestone manufactured by Co., Ltd., and the resulting powder (average particle size: 1.0 to 1.7 μm) having a diameter of 13
mm, a disk-shaped molded body with a thickness of about 1 mm
It was baked at 40-1260 ° C. for 1 hour. After firing, the porcelain was polished to a thickness of about 0.3 mm, and Cr-
An Au deposition electrode was provided. After that, 15
3 kV / mm between both electrodes in silicone oil at 0 ° C
Was applied for 30 minutes for polarization treatment. For this sample, the resonance frequency (fr) and the antiresonance frequency (fa) after the heat treatment at 150 ° C. for 30 minutes were measured and compared with the values before the heat treatment. The results are shown in Table 6 for sample numbers 30 to
Shown at 54.

[0057]

[Table 6]

As is clear from the results in Table 6,
General formula calcined: Pb (A, Nb) _xZr_yTi_1-xyO_Three
(Where x and y are 0 ≦ x ≦ 0.05, 0.35 ≦ y ≦
Is a number that satisfies 0.80, and A is Sn, Zn, Ni and
At least one metal element selected from the group consisting of
And a pre-calcined R
MnO_Three(Where R is Y, Dy, Er, Ho and Yb
At least one metal element selected from the group consisting of
And the subcomponent represented by
The component is Mn_TwoO_Three, R_TwoO_ThreeConverted to 0.01 to 0.05
mol, and then fired piezoelectric ceramic composition (see Table 6).
The sample without the asterisk (*) is the resonance frequency after heat treatment.
Number, the amount of change in anti-resonance frequency, and the amount of drift
It has become smaller. Furthermore, a high electromechanical coupling coefficient (k_t)
Could be obtained.

The main component is Pb (Zn _1/6 Sn _1/6 N
b _2/3 ) _0.03 Zr _0.53 Ti _0.41 O ₃
Even in composite oxides composed of more than one kind of metal element A,
Similar effects were obtained.

Embodiment 6 PbO, Y as raw materials_TwoO_Three, ZnO, NiO, MgO,
Nb_TwoO_Five, TiO_Two , ZrO_Two, MnCO_Three, And Fe
_TwoO_Three, Cr_TwoO_Three, CoO, CuO, SnO_Two Use
And PbO, Y_TwoO_Three, ZnO, NiO, MgO, Nb_Two
O_Five, TiO_Two , ZrO_Two, MnCO_ThreeShown in Table 7
(Y_{(1-x) / 2}Mn_{x / 2}Nb_1/2)_a (M_1/3Nb_2/3)_bZr_cT
i_dO_Three (M is selected from the group consisting of Zn, Ni and Mg
At least one metal element)
Weighed so as to obtain a ratio, and if necessary,_Two
O_Three, Cr_TwoO_Three, CoO, CuO, SnO_Two To Pb (Y
_{(1-x) / 2}Mn _{x / 2}Nb_1/2)_a (M_1/3Nb_2/3)_bZr_cTi_d
O_Three (M is selected from the group consisting of Zn, Ni and Mg
At least one metal element) is shown in Table 7.
After weighing the components in a predetermined proportion,
The mixture was mixed in a mill and calcined at 750 to 900 ° C. for 2 hours. This
The obtained raw material powder is pulverized using a ball mill.
The obtained powder was pressed into a disc-shaped pressure 13 mm in diameter and 1 mm in thickness.
It was pressed into powder. This is heated to 1170-1290 ° C.
And baked for 2 hours. After firing, this porcelain is 0.3m thick
m, and then deposited Cr-Au deposition electrodes on both surfaces.
did. This element was placed in silicone oil at 100 ° C.
Apply a DC electric field of 5 kV / mm between the electrodes for 30 minutes to separate
Polar processing was performed. Next, partially remove the polarized electrode
After that, it becomes more energy trap type resonator
Was formed with a Cr-Au electrode. 250 for this sample
Put the sample for 10 minutes in the oven at
Resonant frequency, anti-resonant frequency, apparent coupling coefficient of resonator
(K ') and capacitance (C)
It was measured by a user. Table 7 shows the measurement results.

[0061]

[Table 7]

As is clear from the above embodiment, Table 7
In the piezoelectric ceramic composition not marked with *, the change in the piezoelectric characteristics before and after the heat treatment is small and the heat resistance stability of the piezoelectric characteristics is improved, for example, as compared with the conventional piezoelectric material (sample No. 1). I have.

In the composition of x = 1 (sample No. 4) which does not include the amount of Y at all, the change rate of the capacitance is not small.

[0064] _{Further, Y (1-x) /} 2 Mn x / 2 coupling coefficient apparent in composition (Sample No.7) content a is 0.18 Nb _1/2 decreases.

When the content b of Zn _1/3 Nb _2/3 is 0.2
The composition (sample No. 12) has a relatively large capacitance change rate.

Further, Pb (Y _1/2 Mn _1/2 Nb _1/2 ) _0.04 (Z
_{n 1/3 Nb 2/3) 0.01 Zr c} Ti d O 3 ( where, 0 ≦ c ≦ 0.
68, 0.3 ≦ d ≦ 0.93) and 0.47 ≦ c ≦ 0.
Compositions in the range of 51, 0.44 ≦ d ≦ 0.48 exhibit relatively large piezoelectricity and are preferred as piezoelectric ceramic materials.

Further, Fe ₂ O ₃ , Cr ₂ O ₃ , CoO, Cu
O or SnO ₂ is converted to Pb (Y _{(1-x) /} 2Mnx _/ 2N
_{b 1/2) a (Zn 1/3 Nb} 2/3) b Zr c Ti d O heat stability is better by adjusting the substitution amount of the metal element by changing the addition amount is ₃ to the composition added It became.

In the case where Zn is an element that forms a composite perovskite even if it is replaced with another divalent transition metal element such as Mg or Ni, almost the same heat resistance stability as in the conventional piezoelectric material is obtained. Can be widely expected.

Embodiment 7 PbO, Y as raw materials_TwoO_Three, ZnO, Nb_TwoO_Five, TiO
_Two , ZrO_Two , MnCO_Three , And Cr_TwoO_ThreeUse
And PbO, Y_TwoO_Three, ZnO, Nb_TwoO_Five, TiO _Two , Z
rO_Two , MnCO_Three To Pb (Y_{(1-x) / 2}Mn_{x / 2}Nb_1/2)_a
(Zn_1/3Nb_2/3) _bZr_cTi_dO_Three(Where x is 0 ≦ x <
1.0 is a number that satisfies 1.0, and ad is 0.01 ≦ a ≦
0.15, 0 ≦ b <0.2, 0 ≦ c ≦ 0.68, 0.3
≦ d ≦ 0.93, a + b + c + d = 1
The composition ratio represented by_TwoO_ThreeTo Pb (Y_{(1-x) / 2}M
n_{x / 2}Nb_1/2)_a(Zn_1/3Nb_2/3)_bZr_cTi_dO_ThreeAgainst
Weighed to 0.2% by weight and then ball milled
The mixture was mixed and calcined at 850 ° C. for 2 hours. And ball mill
Grinding until the average particle size becomes 0.5μm or less
I do. These obtained powders were 7 × 3 mm, 1 mm thick
A rectangular plate-shaped molded body of
For 2 hours. After firing, this porcelain is 0.2mm thick
After polishing, a Cr-Au vapor deposition electrode is applied to both surfaces.
Was. This device was placed in silicone oil at 100 ° C
Polarization by applying DC electric field of 5kV / mm between poles for 30 minutes
Processing was performed. Subsequently, the polarization electrode was partially removed.
Later, together with the vibrator part (resonator part) 3 as shown in FIG.
Energy trapping type with additional capacitance part (unpolarized part) 4
A Cr-Au electrode was formed so as to provide a filter. This
Sample in a 250 ° C oven for 10 minutes
And the change of the filter waveform before and after the heat treatment was measured.
As a result, the filter using the piezoelectric ceramic composition of the present invention
The waveforms before and after the heat treatment are compared with those of the conventional piezoelectric material.
Piezoelectric ceramics with little change in filter waveform and excellent heat resistance
Filter can be provided.

[0070]

As described above in detail, the piezoelectric ceramic composition of the present invention is more effective than the conventional piezoelectric ceramic composition.
Variation of the resonance frequency due to thermal shock and subsequent drift can be suppressed, and more favorable piezoelectric characteristics can be obtained. In other words, it is possible to provide a piezoelectric ceramic composition having a small change in the resonance frequency and the capacitance value before and after the heat treatment and having excellent heat resistance. This piezoelectric ceramic composition is particularly useful from the viewpoint of quality control in the manufacturing process, since the characteristics of the piezoelectric ceramic composition change little with time even after a short-time heat treatment of about 250 ° C.

Further, according to the present invention, a piezoelectric element having excellent heat resistance can be provided by using the piezoelectric ceramic composition. Further, the piezoelectric ceramic filter using the piezoelectric ceramic composition of the present invention, the filter waveform has a small amount of shift in frequency characteristics before and after heat treatment,
A piezoelectric ceramic filter having excellent heat resistance can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a thickness-shear mode piezoelectric element which is an example of the piezoelectric element of the present invention.

FIG. 2 is a perspective view showing a thickness-shear mode piezoelectric ceramic filter which is an example of the piezoelectric element of the present invention.

FIG. 3 is a perspective view showing a piezoelectric ceramic filter which is an example of the piezoelectric element of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Piezoelectric ceramics 2 Electrode 3 Oscillator part (resonator part) 4 Additional capacitance part (unpolarized part)

──────────────────────────────────────────────────続 き Continuing on the front page (51) Int.Cl. ⁶ Identification code FI H01L 41/18 101D (72) Inventor Hiroshi Asano 1006 Odakadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (13)

[Claims] 1. A main component comprising a composite oxide of Pb, Ti and Zr, and Y, Dy, Er, Ho, T as subcomponents
at least one selected from the group consisting of m, Lu and Yb
A piezoelectric ceramic composition comprising a kind of metal element and Mn. 2. A piezoelectric ceramic composition comprising a composite oxide represented by the following general formula (I) as a main component. (1-x) Pb (M 1/3 Nb 2/3) a Zr b Ti c O 3 -xRMn d O 1 + 2d (I) ( wherein, the number x is satisfying a 0 <x ≦ 0.1 , A to c are 0
≦ a ≦ 0.1, 0 ≦ b ≦ 0.7, 0.3 ≦ c ≦ 1.0,
a is a number that satisfies a + b + c = 1, d is a number that satisfies 0.5 ≦ d ≦ 3, M is at least one metal element selected from the group consisting of Zn, Ni and Mg, and R is Y, Dy,
At least one metal element selected from the group consisting of Er, Ho, Tm, Lu and Yb) 3. A composite oxide containing Pb and Ti as a main component, and a metal element R (where the metal element R is Y, D
y, Er, Ho, Tm, Lu and Yb) and Mn are converted to an oxide represented by RMnO ₃ , and A piezoelectric ceramic composition, which is contained in a ratio of 1 to 10 mol% based on the total amount. 4. A piezoelectric ceramic composition comprising a composite oxide represented by the following general formula (II) as a main component. (1-x) Pb (M 1/3 Nb 2/3) a Zr b Ti c O 3 -xRMnO 3 (II) ( wherein, x is number satisfying 0.01 ≦ x ≦ 0.1, a ~
c is 0 ≦ a ≦ 0.1, 0 ≦ b ≦ 0.7, 0.3 ≦ c ≦
1.0, a + b + c = 1, and M is Z
at least one selected from the group consisting of n, Ni and Mg
Seed metal element, R is Y, Dy, Er, Ho, Tm, Lu
And at least one metal element selected from the group consisting of Yb) 5. A metal element R (where R is Y, Dy, E) as a sub-component to a main component represented by the following general formula (III):
at least one metal element selected from the group consisting of r, Ho, Tm, Lu and Yb) is converted to R ₂ O ₃ , and is 0.01 to 0.05 m for each 1 mol of the main component.
ol, and converting Mn to Mn ₂ O ₃ ,
A piezoelectric ceramic composition characterized in that it is contained at a ratio of 0.01 to 0.05 mol per mol. _{Pb (A, Nb) x Zr} y Ti 1-xy O 3 (III) ( wherein, x, y is 0 ≦ x ≦ 0.05,0.35 ≦ y ≦
Is a number that satisfies 0.80, and A is at least one metal element selected from the group consisting of Sn, Zn, Ni, and Mg.) 6. A piezoelectric ceramic composition represented by the following general formula (IV). _{Pb (Y (1-x)} / 2 Mn x / 2 Nb 1/2) a (M 1/3 Nb 2/3) b Zr c Ti d O 3 (IV) ( wherein, x is 0 ≦ x < The numbers satisfying 1.0, ad are 0.01 ≦ a ≦ 0.15, 0 ≦ b <0.2, 0 ≦ c ≦
0.68, 0.3 ≦ d ≦ 0.93, a + b + c + d = 1
And M is at least one metal element selected from the group consisting of Zn, Ni and Mg.) 7. Further, Fe, Cr, Co, Cu and Sn
At least one metal element selected from the group consisting of
Fe ₂ O ₃ , Cr ₂ O ₃ , Co
O, CuO and SnO ₂ , respectively, are converted to 0.01
The piezoelectric ceramic composition according to any one of claims 1 to 6, wherein the piezoelectric ceramic composition is contained at a ratio of about 1.3% by weight. 8. Pb, Ti and Zr calcined in advance
RMnO ₃ (where R is Y, Dy, Er, H
o, Tm, Lu and Yb), followed by mixing and firing. 9. The following general formula (III) calcined in advance:
And the pre-calcined RMnO
₃ (wherein R is one kind of metal element selected from the group consisting of Y, Dy, Er, Ho, Tm, Lu and Yb). 0.01~0.05mol by converting the components _{R 2 O 3, Mn 2 O} 3
A method for producing a piezoelectric ceramic composition, comprising adding 0.01 to 0.05 mol of each of the components, followed by firing. _{Pb (A, Nb) x Zr} y Ti 1-xy O 3 (III) ( wherein, x, y is 0 ≦ x ≦ 0.05,0.35 ≦ y ≦
Is a number that satisfies 0.80, and A is at least one metal element selected from the group consisting of Sn, Zn, Ni, and Mg.) 10. A piezoelectric element comprising the piezoelectric ceramic composition according to claim 1. Description: 11. The piezoelectric element according to claim 10, wherein the vibrator and the capacitor are integrally provided. 12. A piezoelectric ceramic filter using the piezoelectric ceramic composition according to any one of claims 1 to 7. 13. The piezoelectric ceramic filter according to claim 12, wherein the vibrator and the capacitor are integrally provided.