JPH02212334A - Composition for producing resistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a composition used for manufacturing resistors in the electronics field, and in particular to a composition compatible with copper conductors and in a substantially non-oxidizing atmosphere. The present invention relates to a composition for manufacturing a resistor that can be fired at

[Prior art] Current circuit formation for microelectronic components involves
RuO2 and Bi2 Ru2 are placed on an insulating substrate such as an alumina substrate along with a noble metal (thick film) conductor such as Au or Ag/Pd.
A ruthenium-based (thick film) resistor such as 07 is baked in air and used.

On the other hand, in recent years, there has been a strong demand for microelectronic components to be smaller, faster, more accurate, and lower in cost, and there is a need for the practical use of Cu systems that use base metal Cu as a conductor instead of noble metal conductors. . this is,
This is because Cu has extremely high conductivity, does not cause migration unlike Ag-based materials, has excellent solderability, and can be expected to reduce costs.

However, Cu conductors need to be fired in an inert or reducing atmosphere. When firing a Cu conductor together with a ruthenium-based resistor such as the one described above in an inert or reducing atmosphere, the ruthenium-based resistor is reduced to metallic ruthenium and the desired resistance is not achieved. Can't get the body.

After forming the ruthenium-based resistor by firing in air,
A method of suppressing reduction to metallic ruthenium has also been proposed using a binary firing method in which a Cu conductor is formed by firing in an inert atmosphere at about 600°C. However, this method has the problem of poor contact between the Cu conductor and the ruthenium-based resistor. Furthermore, in order to take advantage of the excellent conductivity of the Cu conductor, a resistance paste that can be fired at around 900°C, where the Ca powder is in an optimal sintered state, is required, since the firing temperature of about 600°C is too low. ing.

So far, resistors that can be fired in a non-oxidizing atmosphere at around 900°C and can be used with Cu conductors include:
Resistance pastes such as LaB6 series, Ta/TaN series, and 5n02 series have been proposed, and some are being considered for practical use. However, it has not been possible to obtain excellent characteristics such as the above-mentioned ruthenium-based resistor fired in air.

Furthermore, in these resistance pastes for firing in a non-oxidizing atmosphere, the area near the IOK
Be type, Ta / Ta N type) and high resistance type (Sn
02 series), it is necessary to use resistor pastes with different conductive components.
There is a problem in that the wide resistance range of 0 to 106 Ω/hole cannot be covered by the same type of resistance paste with zero S component.

Furthermore, IOK, which is the most frequently used hybrid IC,
There is also the problem that the characteristics of the mouthed body near the Ω/mouth have not reached the level of practical use.

U.S. Pat. No. 4,420,338 discloses an alkaline earth borate glass containing metal boride as a conductive component and reducing metal oxides such as V, Nb, Ta, and W in an amount of 5 mol % or less as a glass frit. Discloses a resistor comprising:

The reducing metal oxide in this glass frit is added to improve TCR (temperature coefficient of electrical resistance) characteristics. However, as pointed out in JP-A No. 62-122101, this resistor has a significant drop in resistance value during re-firing, and processing instability is a problem.

In JP-A-62-122101, fine particles of metal water boride represented by LaB6 are used as conductive powder, and Ta2
A resistor is disclosed that includes a glass frit containing crystalline glass in which 30 to 5 mol% of 05 is dissolved. In this resistor, Ta205 in the crystalline glass changes to T a B 2 and CaTa011 by the metal hydroboride, contributing to stabilization of the resistance characteristics, but at 5 mol% or less, CaTa0
11 is not formed. Furthermore, the amount of reducing metal oxides other than Ta205 should be 2 mol % or less, preferably 1 mol % or less of the glass. Furthermore, Ta2
As reducing oxides other than 05, Cr2O3, MnO,
Ni01Fed, V205, Na01ZnO, 20
, Cd05pbo, Bi2O3, WO3, Nb205
, MoO3, etc. The reason why reducing oxides other than Ta205 are limited in this way is because of their presence.
It is expected that this is because it becomes difficult to control the conductive components LaB6 and TaB2 or the reaction product CaTa011, and as a result, it becomes difficult to control the electrical characteristics.

However, even if reducing oxides are controlled in this way, the electrical characteristics of the resistor disclosed in JP-A-62-122101 are currently inferior to the ruthenium-based resistor fired in air. In particular, it is difficult to manufacture a resistance range higher than around 10 to 07 mouths.

[Problems to be solved by the invention] Resistance pastes that can be used with Cu conductors and can be fired in a substantially non-oxidizing atmosphere are still in the development stage, and are comparable to ruthenium-based resistor pastes for firing in air. I haven't gotten what I want.

Furthermore, the metal-hole boride-based resistor paste proposed above, which can be fired in a non-oxidizing atmosphere at around 900°C, does not have the resistor characteristics of the ruthenium-based resistor paste for firing in air. In particular, it is difficult to use metal-hole boride-based resistance pastes in a higher resistance range than near the 10 to 07 openings, and there remains great concern in practical terms.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides (a) rare earth borides, alkaline earth borides, borides of group IVa of the periodic table, and borides of group Va of the periodic table. (b) one or more niobium compounds selected from niobium oxides and niobium borides;
c) a glass frit; and (d) an organic vehicle, wherein the amount of the niobium compound exceeds 5 mol% and does not exceed 40 mol% of the glass frit, and the molar ratio to the metal boride. A composition for manufacturing a resistor has been found, which has an angle of 4 to 0°4, is compatible with copper conductors, and can be fired in a substantially non-oxidizing atmosphere.

[Function] Resistance paste used in thick film technology generally consists of conductive powder,
A glass frit and an organic vehicle are used as constituent components. After kneading the constituent components into a paste using a three-roll mill or the like, a circuit pattern is formed on an alumina substrate using a screen printing method or the like, and the desired resistor is formed by drying and firing. It is said that

In the resistor manufacturing composition of the present invention, the conductive powder consists of a metal boride and a niobium compound.

Examples of metal borides include rare earth borides such as LaB6 and CeB6, alkaline earth borides such as BaB6.5r86, borides of group IV a of the periodic table such as TiB2 and Zr82, and borides of group Va such as VB2 and NbB2. One or more metal borides selected from compounds can be used. These metal borides are usually pulverized using a pulverizer such as a ball mill. In particular, the average diameter of LaB6 after micronization is 5NO11 μm, preferably 2 to 0.1 μm.The reason why the average diameter is 5 μm or less is as follows.
In the present invention, a conductive product produced by firing a metal boride and a fine niobium compound described below in a substantially non-oxidizing atmosphere is important, and the average diameter of the metal boride is larger than 5 μm. This makes it difficult to obtain a uniformly conductive product. On the contrary, the reason why the average diameter is set to 0.1 μm or more is that the finer the metal boride is, the more preferable it is.
In order to make the average diameter smaller than 0.1μ stone, it requires extremely long grinding time and contamination from the grinder cannot be ignored, making it impractical.

In addition, as niobium compounds, NbO2, Nb2O3, N
A material selected from niobium oxides and niobium borides such as b205, NbB2, etc. can be used. These react with the metal boride by firing at 800 to 950°C in a non-oxidizing atmosphere to form niobium boride (NbB
, NbB2, etc.), niobium, or a mixture thereof is produced in the resistor.

In order to uniformly deposit these conductors in the resistor and form a stable conductive path, the amount of the niobium compound must exceed 5 mol% and not exceed 40 mol% of the glass frit. In addition, the average diameter of these conductive materials is preferably 1 μm or less, particularly preferably 0.5 μm or less for Nb2O3, the amount of the niobium compound is 5 mol% or less of the glass frit, or the average diameter of the niobium compound is larger than 1 μm. In either case, a uniform conductive path is not formed in the resistor, and the desired resistor characteristics cannot be obtained. This is because chemical substances such as BaNb206 are generated. Also, when the niobium compound exceeds 40 mol% of the glass frit, the reaction between the niobium compound and the metal boride tends to be uneven, unreacted niobium compound remains, and the niobium compound and the glass frit preferentially react. As a result of the reaction, reaction products such as BaNb206 may be generated, making it impossible to obtain desired resistor characteristics.

Further, in the present invention, the total weight of the niobium compound and metal boride and the weight ratio of the glass frit are 5/95 to 60/40.
, preferably 10/90 to 50,150. If the above weight ratio is greater than 60/40, film strength and adhesive strength with the substrate cannot be obtained, and if it is less than 5/95, an appropriate conductive network is not formed and desired resistance characteristics cannot be obtained.

The niobium compound and metal boride have a molar ratio of 4 to 0.4,
Preferably, the range is from 2 to 0.45.

If this molar ratio exceeds 4, a large amount of unreacted niobium compounds may remain, or due to reaction with glass components, BaNb20
The amount of products such as 6 increases, the amount of conductive material contributing to conductivity decreases, and the resistance characteristics of the resistor deteriorate. If the molar ratio is less than 0.4, the amount of conductive material generated by the reaction between the niobium compound and the metal boride is small, and it is only the unreacted metal boride that contributes to conductivity, and the effect of adding the niobium compound is reduced. It is not recognized, and the resistance characteristics on the high resistance side deteriorate.

In the present invention, niobium boride and niobium are generated as conductive powder in the resistor through the reaction as described above, but if these niobium boride and niobium are used as constituent components of the resistance paste from the beginning, the conductive powder Since the wettability of the material and the glass is poor and the material tends to aggregate, it is difficult to obtain a uniform conductive path obtained by firing in a non-oxidizing atmosphere as in the present invention.

The glass frit helps form a conductive network in the resistor during softening, flow, and sintering during firing in a substantially non-oxidizing atmosphere, and the role of resistance adjustment by the conductor and glass 1, as well as the resistance between the substrate and the resistor. It plays the role of adhering the body and improving membrane strength.

As the glass frit, BaOlCaOlSrOlM
gO1Si02, B203, ZrO2,5n02
, TiO2, Al103, etc. can be used.

Glass frit can be manufactured by a conventional method. #I component carbonates and oxides such as BaCO3 and MgO are mixed in a desired ratio, heated and melted, and after quenching, the average diameter is reduced by crushing with a ball mill or the like. It is possible to use one adjusted to about 5 μm.

Among the constituent components of the glass frit, 20 to 50% by weight of alkaline earth borides such as BaO, and 10 to 3% by weight of B2O3.
0 wt%, S i 02 20-30 wt%, ZrO2
It is also preferable that the content of tetravalent metal oxides such as 5n02 and TlO2, which can replace ZrO2, is 10tr amount % or less.

The organic vehicle consists of a solvent, a resin, and a small amount of additives, and allows the resistor paste to be screen-printed to form a predetermined circuit pattern on the board, and does not remain in the resistor by drying and baking in a non-oxidizing atmosphere. Examples of solvents include alcohols, esters, ethers, ketones, etc.
For example, terpineol, ethyl propionate, diethyl dibutyl ether, methyl ethyl ketone, etc. can be used. As the tM resin, for example, cellulose resins such as ethyl cellulose and nitrocellulose, acrylic resins such as butyl methacrylate and methyl methacrylate, etc. can be used.

As additives, lecithin, stearic acid, etc. can be used for purposes such as adjusting the viscosity M of the paste. In the vehicle! IM! The content of the components is usually 1 to 50% by weight.

Incidentally, the organic vehicle accounts for 20 to 20% of the entire composition for producing a resistor.
The amount of the vehicle is 40% by weight, and if the amount of the vehicle is too much or too little, a suitable resistor pattern cannot be obtained by screen printing.The vehicle evaporates or decomposes and disappears during drying and baking.

[Example] LaB6 (manufactured by Nippon Metal Co., Ltd., F grade) was ball milled in an ethanol solvent using a Zirnicore ball (5 m + φ) to form L with a BET average diameter of 0.8 μm.
Instead of using aB6, Nb203 (manufactured by Kojundo Kagaku Kenkyukaku Co., Ltd.) was similarly pulverized and used as a powder with an average diameter of 0.4 μm.

The glass frit contains 48.1% by weight of BaO and B203.
is 20.8% by weight, 5102 is 25.5% by weight, ZrO
It was used in the form of a powder having a composition of 5.7% by weight of No. 2 and an average particle size of about 5 μm.

The vehicle used was terpineol as a solvent and ethyl cellulose as a resin.

LaB6, Nb203, glass frit, and vehicle were mixed in the proportions shown in Table 1 and made into a paste using a three-roll mill. A pattern with a film thickness of 40 μm was formed on an alumina substrate by forming a Cu1J electrode in advance using this paste according to the usual thick film method, and after leveling for 30 minutes, it was dried at 120°C for 10 minutes, and a belt was placed in a nitrogen atmosphere. A resistor was formed by firing in a conveyor furnace. Firing was carried out at a maximum temperature of 900° C. for 10 minutes for a total firing time of 1 hour.

The coefficient of variation (CV) of the resistance value was calculated using the formula shown below.

Where: n=number of samples Ri=, resistance value of sample l (Ω/mouth) temperature coefficient of resistance & (TCR) is -55℃, 25℃, 12
Each resistance value at 5° C. was measured, and the cold temperature coefficient (CTCR) and ripe temperature coefficient (HTCR) were calculated using the following formulas.

Where: R-ss: s Resistance value at °C (Ω/
) R: Resistance value at 25° C. (Ω/mouth) R125: Resistance value at 125° C. (Ω/mouth) Current noise was measured using a noise meter (manufactured by Quan-Tach).

The adhesion speed of the resistive film was evaluated from the peeling state using an adhesive tape test. The results are shown in Table 1.

Table 1 shows comparative examples prepared in the same manner, which are outside the scope of the claims of the present invention in that the molar ratio of the niobium compound to the metal boride is not within the range of 4 to 0.4. ! (with a book) is also shown together.

As is clear from Table 1, Comparative Example 1 has a large CV value, a negative TCH value that is too large, or a low film strength, making it a resistor that can withstand practical use. - The resistor obtained from the resistor paste of Rikiki's invention shows good resistor properties.

Table 1 O: Can withstand practical use ×: Not practical The body shows good resistor properties.

(Left space on this page) Dog Iλ NbO2, TiB2, NbB2, CeB6 and 5r
B6 is a powder manufactured by Kojundo Kagaku Kenkyushin Co., Ltd., and VB2 is a powder manufactured by Shin Nippon Metal Co., Ltd. As the raw material, these powders are used to obtain a BET average of 0.2 to 0.6 μm as in Example 1. It was made into a paste and evaluated in the same manner as in Example 1, except that it was ground to a diameter before use. The results are shown in Table 2.

Table 2 shows a plate prepared in the same manner as Example 2, although it is outside the scope of the claims of the present invention in that the molar ratio of the niobium compound to the metal boride is not in the range of 4 to 0.4. Comparative Example 2 (marked with *) is also shown.

As is clear from Table 2, Comparative Example 2 has a large CV value, a negative TCH value that is too large, or a resistor whose film strength is too weak to withstand practical use. -Resistance obtained from the resistance paste of the old invention' Table 2 Comparative example (Sr86 / VB2 = 1/1) A diniobium compound ○: Tolerable for practical use B: Metal boride X: Not for practical use [Effects of the invention ] As described above, according to the present invention, a composition for manufacturing a resistor comprising a niobium compound, a metal boride, a glass frit, and an organic vehicle is fired in a substantially non-oxidizing atmosphere. It is possible to cut a wide resistance range from 101 to 106 ohms/hole and can be used with copper conductors.

Claims (1)

[Claims] (a) one or more metal borides selected from the group consisting of rare earth borides, alkaline earth borides, borides of group IVa of the periodic table, and borides of group Va; (b) niobium oxide and niobium borides; comprising one or more niobium compounds selected from compounds, (c) a glass frit, and (d) an organic vehicle, the amount of the niobium compound being more than 5 mol% and more than 40 mol% of the glass frit. and the molar ratio to the metal boride is 4.
-0.4.