JPH01226111A - Voltage-dependent non-linearity resistor ceramic composition - Google Patents

Abstract

PURPOSE:To increase dielectric constant, voltage non-linearity index, surge withstand amount, etc., by incorporating a third element ThN2 in a voltage- dependent non-linear resistor ceramic composition consisting of the main element of a first element SrTiO3 and metal oxide of a second element. CONSTITUTION:A third element ThN2 of 0.001-5.000mol% is contained within a voltage-dependent non-linear resistor ceramic composition consisting of the main element of a first element of 90.000-99.998mol% and the metal oxide of a second element of 0.001-5.000mol%. The first element consists of at least one type out of SrTiO3, CaXSr1-XTiO3 (0.001<=X<=0.5), BaySr1-yTiO3 (0.001<=y<=0.5), MgzSr1-ZTiO3 (0.001<=Z<=0.5). The second constituent consists of at least one type out of Nb2O5, Ta2O5, WO3, Dy2O3, Y2O3, La2O3, CeO2, Sm2O3 Pr6O11, and Nd2O3. It allows the dielectric constant, voltage non-linear index, surge withstand amount, etc., to be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to voltage dependence devices having capacitor characteristics and varistor characteristics for protecting semiconductors and circuits from abnormal high voltages, noise, and static electricity generated in electrical equipment and electronic equipment. It is related to non-direct @ low antibody porcelain Mi theory.

Conventional technology Conventionally, SiC varistors with voltage-dependent non-linear resistance and Z
nO type varistors were used. The viewing pressure-tortoise current characteristic of such a varistor can be expressed approximately as shown in the following equation.

I=(V/C)a Here, engineering is current, V is 1E voltage, C is a constant specific to the varistor, and α is a direct pressure nonlinear index.

The α of SiC varistors is about 2 to 7, and the α of some ZnO-based varistors is as high as 60. Although such varistors have excellent performance in absorbing relatively high voltages, their low dielectric constant and small inherent capacitance prevent them from absorbing relatively low (pressures) below the varistor direct pressure. It shows almost no effect on the surface, and the dielectric loss -δ is as large as 6 to 10%.

On the other hand, semiconductor capacitors with an apparent dielectric constant of 6×10 4 degrees and −δ of around 1 are used to remove these low-voltage noises. However, if a voltage or current exceeding a certain limit is applied to such a semiconductor capacitor due to a surge or the like, it may break down and no longer function as a capacitor.

Therefore, recently, a product containing 5rTiO as the main component and having both the functions of a custom varistor and a capacitor has been developed, and is used to protect semiconductor elements such as ICs and LSIs in electronic devices such as microcomputers. .

Problems to be Solved by the Invention The above-mentioned 5rTiO-based varistor has a large induction t=i of about 10 tones compared to the ZnO-based varistor, but its voltage nonlinear melting a(α) and surge resistance are small. Since the intragranular resistance was high, it had the disadvantage of not being able to absorb noise sufficiently.

Therefore, an object of the present invention is to provide a voltage-dependent, non-linear, low-resistance porcelain composition that has a large dielectric constant, a large α, a large surge resistance, and a low intragranular resistance.

Means for Solving the Problems In order to solve the apex, in the present invention, 5rTiO
3, Fe2O3, CaXSr, xTiO, (2) SrT
iO3, CaxSr1-xTiO3 (0.001≦x≦
0.5).

BaySrl-y Tie, (2) SrTiO3,C
axSr1-xTiO3 (0.001≦y≦0.5).

Mg, Sr, -zTie, (2) SrTiO3, Ca
xSr1-xTiO3 (0.0CN≦z≦0.5) C
At least one or more of the following (hereinafter referred to as the third component)
0-000~99-997 m OIY;, Nb
20 s, Ta 2Q 5゜wo, , D72
0. , τ20. , La2O3, CeO2, Sm2
0. .

Pr60. , , Nd2O, (hereinafter referred to as the second component)
At least one type of 0.001~s, ooQ
mo6% ThN2 (hereinafter referred to as the third component) is 0.001
~es, containing 1% ooomol, or the first above.

On top of the second and third components, an additional 120. ．． 5b20
．． .

! 3ao, BeO, PbO, B20. , CeO2
,0r20. .

Fe2O3, CdO, K2O, CaO, Co20. ,
CuO.

Cu2O, Li□O, MgO, MnO2, MoO3, N
a2O.

NiO, RhO, 5ea2. AJ20, 5in2
．． SiCISrO, Tl2O, ThN2. Tie2
．． V2O5, Bi2O3゜ffo, , ZnO, Z
At least one type of rO2, 5nO2 (hereinafter referred to as the fourth component). , Oo1~10.000 no1%
The object of the present invention is to solve the problems of obtaining a pressure-dependent nonlinear low antibody composition containing the present invention.

Function: In the above invention, the first component is the main component, and the third component is a metal chloride which mainly promotes semiconductor formation. Further, the third component contributes to improving dielectric -8 and intragranular resistance, and the fourth component contributes to improving dielectric strength α and surge resistance. In particular, the third component is uniformly dispersed throughout the device, and is a nitride at the time of addition, but when heat-treated in air after drying, it changes into a dredged material and emits electrons.

That is, a large amount of diffused dren forms an insulating proboscis at the grain boundary, and the emitted electrons are immersed in oxygen ions, thereby insulating the grain boundary. On the other hand, most of ThN2 exists in the form of nitride because it is difficult for oxygen to diffuse inside the particle, and even if oxygen diffuses into the inside of the particle, the valence of the nitride changes and electrons are emitted. ,
Oxidation: (Acts to suppress the increase in resistance due to oxidation. This can lower the resistance inside the particles.

Actual foam example The present invention will be specifically described below with reference to Examples.

First, 5rCO3, Fe2O3, CaC2)SrTiO
3, CaxSr1-xTiO3(0., BaC2)Sr
TiO3, CaxSr1-xTiO3(0., MgC2
) SrTiO3, CaxSr1-xTiO3 (0.

Weigh TiO2 so that it has the composition shown in Table 1 below, mix it in a ball mill etc. for 404 minutes, dry it, and then
15 Samurai slopes and slopes at 000℃. The thus obtained calcined product '7CMo2N and the whole mixture were weighed so as to have the composition shown in Table 1, mixed in a ball mill for 24 hours, dried, and then mixed with an organic binder such as polyvinyl alcohol. After adding IQwt% and granulating, 1 (t/, f
It is molded into a disk shape of 10φX1 (Iff) with a press pressure of fl ). Then, after applying a binder at 1060° C. for 1 hour in air, the mixture was heated at 1400° C. in a mixed gas of N2:H2=9:1. moreover,
A conductive paste such as mug was applied to both planes of the thus-obtained material 1 shown in FIGS. Apply by screen printing or the like and heat at 600'C for 16 minutes to form electrolyte 2.3. Next, although not shown, attach the lead wires with solder, etc., and
Paint with fingers. The characteristics of the device thus obtained are shown in Table 2 below.

In addition, in Table 2, the dielectric constant ε) is calculated from the static flood capacity at the hermitage, and the intragranular resistance XSR is estimated by the impedance at the dust frequency: 11iL, α is a =
1/Log (vjomA/v+mh) (however, vlmA I 10 mA is the voltage applied to both ends of the element when a current of 1 mm and 10 mm is passed). In addition, the amount of one surge is evaluated by the maximum pulse current [directly] when the change in viml after applying the pulse current is within ±10%.

(Left below) Also, the first component 5rTiO3, Fe2O3, CaxS
r, -xTiO.

(2) SrTiO3, CaxSr1-xTiO3 (0.
001≦x≦o, s>, BaySr, -yTie
.

(2) SrTiO3, CaxSr1-xTiO3 (0.
001≦y≦0.5), Mg2Sr, -2Tie.

(2) SrTiO3, CaxSr1-xTiO3 (0.
001≦z≦0.6), , 7.2 (7), @il'
Is it effective if it is less than 0.001? Not shown, 0
．． This is because if the number 6 is removed, granulation and semi-conducting will be suppressed and the custom-made product will deteriorate. Furthermore, the second component o, ool m
ol! % end cocoon does not show any effect, and when it exceeds 6.000 mol%, it segregates at the grain boundaries and increases the resistance of the grain boundaries. This results in deterioration of properties due to the formation of a secondary structure at the grain boundaries.

If the second component is less than 0.001 mol %, it will not be effective, and if it exceeds s,oomo/%, a second phase will be formed at the grain boundaries, resulting in deterioration of the properties. Also, Chapter V5
The A component does not exhibit the -i effect at 0.001 nod%, and when it exceeds s, o o o no/, a second phase is formed at the grain boundaries, grain growth is suppressed, and the resistance of the grain boundaries is reduced. becomes higher, but the 7th field becomes thicker, so the static capacitance becomes smaller and the varistor voltage becomes higher, making it weaker against surges.

Although this practical example only shows some combinations of additives, other attachments may be included if they are within the scope of the claims.
It was confirmed that a similar effect exists for the combination of objects.

Effects of the Invention As shown above, according to the present invention, the dielectric constant ε, the pressure non-linearity index a are large, and the intragranular resistance is small, so that it is possible to absorb high-frequency noise and suppress surge currents. Since A generates less heat after being exposed to heat, it is possible to achieve the effects of less deterioration of the element and increased surge resistance.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an element according to the invention, and FIG. 2 is a sectional view showing the element according to the invention. 1...Acinated body, 2.3...Voltage. Name of agent: Patent attorney Toshio Nakao and one other person Sintered body? electrode

Claims (2)

[Claims] (1) SrTiO_3, Ca_xSr_1_-_xTi
O_3 (0.001≦x≦0.5), Ba_ySr_1
____yTiO_3 (0.001≦y≦0.5), Mg
_zSr_1_−_zTiO_3 (0.001≦z≦0
．． 90.000 to 9 for at least one of the following
9.998mol%, Nb_2O_5, Ta_2O_5
, WO_3, Dy_2O_3, Y_2O_3, La_2
O_3, CeO_2, Sm_2O_3, Pr_6O_1
At least one of _1, Nd_2O_3 is 0
．． 001-5.000 mol%, ThN_2 0.00
A voltage-dependent nonlinear resistor ceramic composition containing 1 to 6.000 mol%. (2) SrTiO_3, Ca_xSr_1_-_xTi
O_3 (0.001≦x≦0.5), Ba_ySr_1
____yTiO_3 (0.001≦y≦0.5), Mg
_zSr_1_−_zTiO_3 (0.001≦z≦0
．． 6) at least one type from 80,000 to 9
9.997mol%, Nb_2O_5, Ta_2O_5
, WO_3, Dy_2O_3, Y_2O_3, La_2
O_3, CeO_2, Sm_2O_3, Pr_6O_1
At least one of _1, Nd_2O_3 is 0
．． 001-5.000 mol%, ThN_2 0.00
1 to 5.000 mol%, Al_2O_3, Sb_2O
_3, BaO, BeO, PbO, B_2O_3, CeO
_2, Cr_2O_3, Fe_2O_3, CdO, K_
2O, CaO, Co_2O_3, CuO, Cu_2O,
Li_2O, MgO, MnO_2, MoO_3, Na_
2O, NiO, Rh_2O_3, SeO_2, Ag_2
O, SiO_2, SiC, SrO, Tl_2O, ThO
_2, TiO_2, V_2O_5, Bi_2O_3, W
The present voltage-dependent nonlinear resistance ceramic composition contains 0.001 to 10.000 mol% of at least one of O_3, ZnO, ZrO_2, and SnO_2.