JPH0738325B2 - Thick film resistor composition and use thereof - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thick film resistance composition used for a thick film hybrid IC and the like, and a thick film hybrid IC using the same.

[Conventional technology]

Conventionally, as a resistor material used in a thick film hybrid IC or the like, a RuO ₂ based material has been generally used because it can be fired in air. Therefore, the conductor circuit was also made of Ag-Pb-based material that would not be oxidized even if it was fired in air.

However, Ag-Pb materials have a relatively high resistance value, and have been a link for lowering the impedance of thick film hybrid ICs. On the other hand, the copper-based circuit conductor has an advantage that it has a lower impedance than the Ag-Pb-based circuit conductor, but since copper is easily oxidized, it can be fired only in a non-oxidizing atmosphere, for example, in nitrogen gas. Further, when the above RuO ₂ type material is used as the resistance material, there is a problem that it cannot be used because RuO ₂ is reduced in nitrogen gas. Therefore, as a resistance material in a thick film hybrid IC having a copper-based conductor circuit,
A metal hexaboride (for example, LaB _{6) in} which glass powder and an organic vehicle are added (Japanese Patent Publication No. 59-51721) is known.

However, these have a problem that a stable resistor having a sheet resistance of several KΩ / □ or more cannot be obtained.

[Problems to be Solved by the Invention]

The metal 6 boride centered on LaB ₆ realizes stable resistance characteristics as a thick film resistor by combining with a borosilicate glass. However, this resistor is practically 10 ~
Only 10 ⁴ Ω / □ is satisfied. Among the metal borides, IVa, Va, VIIa, and VIII borides are superior to those having 6 or more borides, which are excellent in electrical conductivity, melting point, and chemical stability. However, since these borides have poor wettability with ordinary borosilicate glass, they cannot be used as conductive particles for thick film resistors. Compared to compounds containing rare earth elements such as LaB _6, these are easier and cheaper to work with.
It is an object of the present invention to develop a technique in which a boride of Group IVa, Va, VIIa or VIII can be used as a conductive particle of a thick film resistor.

[Means for Solving the Problems]

Briefly describing the present invention, the first invention of the present invention relates to a thick film resistor composition, comprising (a) Periodic Table IVa, Va, VI
2 to 70 parts by volume (all solids basis) of at least one boride selected from the group consisting of borides of Group Ia and VIII metals, (b) within 0.02 nm in the metal and ionic radius of the above boride. Powder of 8 to 30 parts by volume (all solids basis) of a glass containing 1 to 30 parts by weight of the metal oxide in 1), capable of firing in a non-oxidizing atmosphere, and not reduced by the above boride upon firing. And a effective amount of an organic vehicle.

A second invention of the present invention relates to a thick film hybrid IC, which is a thick film hybrid IC having a thick film conductor and a thick film resistor on a substrate made of a ceramics sintered body.
In the above, the resistor is a sintered body of the thick film resistor composition of the first invention.

The object is achieved by improving the wettability of metal borides with, for example, borosilicate atumi glass. In order to improve the wettability, the metal boride and the metal oxide having an ionic radius within 0.02 nm are added to the borosilicate aluminum glass.

The metal 6 boride such as LaB ₆ has good wettability with the aluminum borosilicate glass because the metal in the metal oxide added to adjust the softening point such as CaO contained in the glass,
This is because the ionic radii of metals in borides are very close to each other (see Table 1).

If the ionic radii are close in size, it is easy to exchange the positions of atoms with each other. Therefore, if the metal atoms in the conductive particles and the metal atoms in the glass are exchangeable, the energy of the interface formed by them becomes low and the wettability becomes good.

According to this mechanism, even in a general conductive metal boride, by adding a metal oxide having an ionic radius similar to that of the metal of the boride to the glass, the wettability with the glass is improved. It can be used as conductive particles for thick film resistors. In that case, it is necessary that the added oxide does not hinder vitrification.

The thick film resistor has a structure in which conductive particles are bonded to each other by glass. Therefore, if the amount of glass is too small, the conductive particles cannot bond with each other, and it becomes difficult to pass an electric current, and the adhesiveness to the substrate deteriorates. Also,
If the amount of the conductive particles is too small, the chain of the conductive particles will be broken and the conductive path cannot be formed. Taking these into consideration, the conductive component in the thick film resistor is preferably 2 to 70 parts by volume (based on all solids).

Further, in order to stably realize the high resistance range, it is necessary to form a thin conductive path of conductive particles in the resistor. For that, the particle size of the conductive particles must be small, 0.
It is preferably 5 μm or less, more preferably 0.1 μm or less.

The boride particles are preferably generated using a heat source such as arc plasma or high frequency induction plasma.

Particularly preferred as the metal in the boride of the present invention is
There are Ti, Zr, Hf as the IV group, V, Nb, Ta as the V group, Mn as the VIIa group, and Fe, Co, Ni as the VIII group.

By combining a metal boride having such a small particle size and glass having improved wettability with the boride, 10 to 10
It is possible to develop a stable new thick film resistor that covers the resistance value range of ⁶ Ω / □ and has good temperature characteristics of resistance.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples.
The present invention is not limited to these examples.

Example 1 A powder of a boride of group IVa and Va was melted and quenched by an induction plasma method to prepare a fine powder of 0.5 μm or less. From Table 1, hafnium was selected as a metal for improving the wettability, and an aluminum borosilicate glass to which hafnium oxide was added was prepared. The composition is shown in Table 2.

After mixing these conductive powders and glass powder with a frying machine, add 20% methacrylic acid-based resin / butyl carbitol acetate solution as an organic vehicle to about 20 parts of the powder component.
% By weight and kneaded at room temperature using a three-roll mill to obtain a thick film resistor composition of the present invention in a paste form.

Next, the resistor shown in FIG. 1 was produced. That is, the first
FIG. 1 is a plan view of a test resistor used in one embodiment of the present invention. Reference numeral 1 is an alumina substrate, 2 is a Cu conductor, and 3 is a resistor. As shown in Fig. 1, alumina substrate 1 (0.8m
Cu conductor 2 by a screen printing method using a copper-based conductor paste (Dyupon Co., Ltd .: 9153) on m × 72 mm × 55 mm)
After forming, dry at 120 ℃, 10 minutes, 900 ℃, 10 in nitrogen gas
Minutes were fired.

Next, the thick film resistor composition was similarly printed to form a resistor 3. This was dried at 120 ° C. for 10 minutes and then fired at 950 ° C. in nitrogen gas to produce a resistor.

Table 3 shows the sheet resistance and TCR for each composition of TiB ₂ series resistors.
(Resistance temperature coefficient) is shown. Further, Table 4 shows the sheet resistance and TCR for each composition of the TaB type resistor.

Comparative Example 1 As a glass powder, borosilicate aluminum glass containing no hafnium oxide was prepared (see Table 2), mixed with TiB ₂ used in Example 1, and a resistance paste was prepared by the same process as in Example 1. . Then, in the same manner as in Example 1, the conductor paste and the resistance paste were printed and fired on the alumina substrate to manufacture a resistor. Table 5 shows the sheet resistance and TCR for each composition.

The resistance value of the resistor manufactured here covers only a high value region, and most of the TCR has a large negative value, which is unstable as a thick film resistor. This is because the glass does not wet well with TiB _{2 as} compared with Example 1. This is because the glass used in Example 1 contains Hf ions having an ionic radius close to that of Ti ions and easily forms the interface between the glass and the boride, whereas the glass used in Comparative Example 1 In glass, metal ions having an ionic radius close to that of Ti ions are not contained in the glass, so that it is difficult to form the interface between the glass and the boride. As mentioned earlier, if the conductive particles and glass have good wettability, the conductive particles are firmly bonded to each other, and the resistance value range desired from 10 Ω / □ to 10 ⁶ Ω / □ is desired for thick film resistors. Can be realized. On the other hand, if the wettability is poor, the bonding between the conductive particles does not proceed well, so that the low resistance value range cannot be realized.

The difference in the wettability between the glass and the conductive particles appears as the difference between Table 3 and Table 5 in the thick film resistor having TiB ₂ as the conductive particles.

Comparative Example 2 In order to compare the wettability between the metal boride and the glass, the wetting angle of the pellet-shaped (15φ × 5 mmt) metal boride was changed by heating the pellet-shaped (10φ × 3 mmt) glass. The measurement was performed (Fig. 2). That is, the 2-1
FIGS. 2-2 and 2-3 are side views of test pieces for evaluating wettability used in other examples of the present invention, and reference numeral 4
LaB ₆ sintered body, 5 means TiB ₂ sintered body, 6 means glass (without HfO ₂ ), and 7 means glass (containing HfO ₂ ). Also, the third
The figure is a side view of the test piece showing the definition of the wetting angle. In measuring the wetting angle, the heating temperature is the softening temperature of the glass,
Hold for 10 minutes. Table 6 shows combinations of metal borides and glass and wetting angles.

It can be seen that the use of glass containing hafnium oxide also improves the wettability of TiB ₂ with glass.

Embodiment 2 FIG. 4 is a diagram showing patterns of conductors and resistors of a thick film hybrid IC for a high frequency amplifier circuit, and reference numerals 1 to 3 are synonymous with FIG. Cu for conductor (Deupon: 9153)
Was used. For the resistor, TiB ₂ produced in Example 1 was used.
-Five types of glass type (No. 1, 2, 4, 5, 6 in Table 3) were used. Since the resistor covers the entire resistance range required for one component, it is not necessary to incorporate a chip resistor.

Example 3 A fine powder of MnB ₂ as a boride of Group VIIa was used as a conductive powder. The resistivity of MnB ₂ is 71 μΩ · cm. The Mg ion is selected as one close to the ionic radius of this Mn ion,
This oxide, MgO, was added into the glass. The composition of the glass is shown in Table 7.

After mixing these conductive powders and glass powders with a frying machine, use 20% methacrylic resin / organic resin as an organic vehicle.
Butyl carbitol acetate solution to the powder component,
Add about 20% by weight and knead at room temperature using 3 rolls.
A thick film resistance composition of the present invention in the form of a paste was obtained.

Next, as shown in Fig. 1, the alumina substrate 1 (0.8 mm x 72 m
m × 55mm), copper-based conductor paste (made by Deupon: 91
53) was used to form a Cu conductor 2 by a screen printing method, followed by drying at 120 ° C. for 10 minutes and firing in nitrogen gas at 900 ° C. for 10 minutes.

Next, the thick film resistance composition was similarly printed to form a resistor 3. This was dried at 120 ° C. for 10 minutes, and then baked at 950 ° C. in nitrogen gas to manufacture a resistor.

Table 8 shows the sheet resistance and TCR for each composition of MnB ₂ series resistors.
(Resistance temperature coefficient) is shown.

Example 4 A fine powder of NiB as a boride of Group VIII was used as a conductive powder. The resistivity of NiB is 50 μΩ · cm. Mn ions were selected as those having an ionic radius close to that of Ni ions, and MnO ₂ which was this oxide was added to the glass. Table 9 shows the composition of the glass.

After mixing these conductive powders and glass powders with a frying machine, use 20% methacrylic resin / organic resin as an organic vehicle.
Butyl carbitol acetate solution to the powder component,
About 20% by weight was added, and the mixture was kneaded at room temperature using a triple roll to obtain a thick film resistance composition of the present invention in a paste form.

Next, as shown in Fig. 1, the alumina substrate 1 (0.8 mm x 72 m
m × 55mm), copper-based conductor paste (made by Deupon: 91
53) was used to form a Cu conductor 2 by a screen printing method, followed by drying at 120 ° C. for 10 minutes and firing in nitrogen gas at 900 ° C. for 10 minutes.

Next, the thick film resistance composition was similarly printed to form a resistor 3. This was dried at 120 ° C. for 10 minutes, and then baked at 950 ° C. in nitrogen gas to manufacture a resistor.

Table 10 shows the sheet resistance and TCR (temperature coefficient of resistance) for each composition of MiB series resistors.

Example 5 In order to compare the wettability between a metal boride and glass, various metal borides and aluminum borosilicate glass were prepared. The wetting angle was measured by placing a pellet-shaped (10φ × 3mmt) glass on a pellet-shaped (15φ × 5mmt) metal boride and heating it. The heating temperature was 880 ° C., which is the softening temperature of the glass, and the temperature was maintained for 10 minutes. The measurement result of the wetting angle is shown in FIG. Here, the horizontal axis represents the ionic radius (Å) of the metal ions forming the metal boride, and the vertical axis represents the wetting angle (degree). In addition, the ionic radius of Ca, which is a modifying ion in the glass used here, is also shown for reference. From FIG. 5, it can be seen that the wettability between the glass and the metal boride made of a metal having an ionic radius close to that of Ca is good. According to this result, in order to improve the wettability between the conductive particles in the resistor and the glass and improve the electrical properties of the resistor, the ionic radius of the modifying ion in the glass and the ion of the metal forming the metal boride are It can be seen that the radii need to be close.

Example 6 A method for manufacturing a thick film resistor using TiB ₂ ultrafine particles generated by using an arc plasma heat source will be described.

First, TiB ₂ having a particle size of several μm obtained by a mechanical grinding method
The powder is molded into a molded body. The diameter of the molded body is 30 m
m, thickness is 5 mm. Then, using this molded body as a base material,
An arc is generated between the electrode and the W electrode, TiB ₂ is evaporated in a plasma heat source generated by the arc, and the TiB ₂ is collected after quenching to produce TiB ₂ ultrafine particles. At this time, the atmosphere gas was Ar + 50% H ₂ , and 40 V, 150 A was applied between the electrode and the base material. From this, it was possible to obtain TiB ₂ ultrafine particles having a particle diameter of 0.1 μm or less and having a spherical shape with a smooth surface. As a glass having good wettability with the TiB ₂ ultrafine particles, HfO ₂ powder was added to ordinary borosilicate glass in consideration of the ionic radius of Ti to prepare a glass. Table 11 shows the composition ratio of the oxide raw materials used.

After mixing, these oxide powders were mixed in a platinum crucible for about 15 times.
It is melted at 00 ° C, poured into cold water, crushed through a crushing process and made into frits. After mixing these TiB ₂ ultrafine particles and glass powder with a frying machine, add about 20% by weight of acrylic resin / butyl carbitol acetate solution to the powder component as an organic vehicle, and knead at room temperature using 3 rolls. ,
A thick film resistance composition of the present invention in the form of a paste was obtained.

A pattern was formed from this thick film resistance composition on the alumina substrate on which the Cu conductor was printed and fired by the screen printing method in the same manner as in Example 1. This is dried at 120 ℃ for 10 minutes, then N
Firing was performed in ₂ gases at 900 ° C for 10 minutes. Table 12 shows the measurement results of the sheet resistance, the temperature coefficient of resistance, the variation in resistance, and the current noise of 10 types of resistors having different compositions of the conductive phase and the glass phase.

The variation in resistance value is the average sheet resistance of 20 resistors,
It was calculated by the ratio of the standard deviations. These resistors are
It covers the resistance value range of 10 to 1 MΩ / □ desired for thick film resistors and has a small resistance temperature coefficient within ± 300 ppm.

Example 7 A method of manufacturing a thick film resistor using TaB ultrafine particles generated by using a high frequency induction plasma heat source will be described. First, Ar + He, which is the atmospheric gas, is turned into plasma in a high-frequency induction coil under an input condition of 10 kV-1A, and then TaB particles having a particle size of several μm obtained by a mechanical grinding method are used in this plasma. Inject. TaB evaporates instantaneously in this plasma, but as soon as it comes out of the plasma, it is rapidly cooled and solidified,
Ultra fine particles of TaB can be obtained.

As a glass having good wettability with TaB ultrafine particles obtained by a high frequency induction plasma heat source, HfO ₂ powder was added to ordinary borosilicate glass in consideration of the ionic radius with Ta to prepare glass. Table 11 shows the composition ratio of the oxide raw materials used.
These oxide powders are glass fritted using the same process as in Example 6. After mixing these TaB ultrafine particles and glass powder with a smasher, add about 20% by weight of acrylic resin / butyl carbitol acetate solution as an organic vehicle to the powder component and knead at room temperature using a three-roll mill. A paste-like thick film composition of the present invention was obtained.

This thick film resistance composition was patterned by a screen printing method on an alumina substrate on which a Cu conductor was printed and fired in the same manner as in Example 6. This was dried at 120 ° C. for 10 minutes and then baked at 900 ° C. for 10 minutes in N ₂ gas. Table 13 summarizes the measurement results of the sheet resistance, the temperature coefficient of resistance, the variation in resistance, and the current noise of ten types of resistors having different compositions of the conductive phase and the glass phase.

The variation in resistance value is the average sheet resistance of 20 resistors,
It was calculated by the ratio of the standard deviations. These resistors are
It covers the resistance value range of 10 to 1 MΩ / □ desired for thick film resistors and has a small resistance temperature coefficient within ± 300 ppm.

〔The invention's effect〕

According to the present invention, even without using a metal boride containing a rare earth element such as LaB ₆ , electrical characteristics, chemical resistance is superior to them, and easily available metal boride, conductive particles for thick film resistors. Can be By using these conductive particles and non-reducing glass, a new thick film resistor in fired in nitrogen can be manufactured.

[Brief description of drawings]

FIG. 1 is a plan view of a test resistor used in one embodiment of the present invention, FIGS. 2-1 and 2-2 and 2-3 are wetting used in another embodiment of the present invention. Side view of the test piece to evaluate the
FIG. 3 is a side view of a test piece showing the definition of the wetting angle, FIG. 4 is a view showing conductors and resistors patterns of a thick film hybrid IC for a high frequency amplifier circuit, and FIG. 5 is one embodiment of the present invention. 5 is a graph showing the wettability between the metal boride used in Example 1 and glass by the relationship between the wetting angle and the ionic radius. 1 ... Alumina substrate 2 ... Cu conductor 3 ... Resistor 4 ... LaB ₆ sintered body 5 ... TiB ₂ sintered body 6 ... Glass (without HfO ₂ ) 7 ... Glass (with HfO ₂ )

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Ogawa 4026 Kuji Town, Hitachi City, Hitachi, Ibaraki Prefecture Hitate Manufacturing Co., Ltd.Hitachi Research Laboratories (72) Inventor Mitsuru Hasegawa 4026 Kuji Town, Hitachi City, Ibaraki Prefecture Nitate Manufacturing Co., Ltd. Hitachi Research Laboratory (72) Inventor Akira Ikegami 4026 Kuji-machi, Hitachi City, Ibaraki Prefecture Hitate Works, Ltd.Hitachi Research Laboratory (72) Inventor Yoshishige Endo 502 Jinmachi-cho, Tsuchiura City, Ibaraki Machinery Research Institute, Hitate Co., Ltd. 72) Inventor Mitsuo Otani 1712 Shisui, Shisui-machi, Inba-gun, Chiba Prefecture (72) Katsuo Ebisawa 982 Maeda, Ibaraki-cho, Higashi-Ibaraki-gun, Ibaraki Prefecture (56) Reference JP-A-54-149899 (JP, A) JP-A 55-27700 (JP, A) JP-A-63-202001 (JP, A)

Claims (5)

[Claims] (A) 2 to 70 parts by volume (based on total solids) of at least one boride selected from the group consisting of borides of metals of groups IVa, Va, VIIa and VIII of the periodic table, (b) A glass that contains 1 to 30 parts by weight of an oxide of a metal that is within 0.02 nm in a metal and an ionic radius of the boride, can be fired in a non-oxidizing atmosphere, and is not reduced by the boride by firing. 8 to 30 parts by volume (based on total solids) of each powder, and an effective amount of an organic vehicle, a thick film resistor composition. 2. The thick film resistor composition according to claim 1, wherein the boride has a particle size of 0.5 μm or less. 3. The thick film resistor composition according to claim 1, wherein the boride particles are produced using an arc plasma heat source. 4. The thick film resistor composition according to claim 1, wherein the boride particles are produced by using a high frequency induction plasma heat source. 5. A thick film hybrid IC comprising a thick film conductor and a thick film resistor on a substrate made of a ceramics sintered body, wherein the resistor is a fired body of the thick film resistor composition according to claim 1. Thick film hybrid IC characterized in that