JP2839551B2 - Resistance composition, circuit board and electronic device using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[Industrial Application Field] The present invention relates to a resistor composition for non-oxide ceramics, a circuit board on which a resistor is formed using the same, and an electronic device equipped with the circuit board. [Prior Art] Non-oxide ceramics, for example, aluminum nitride and silicon carbide have attracted attention as substrate materials for electronic components with the improvement of sintering technology and purification technology in recent years.

[1] IEEE Trans. On CHMT, CHMT-8, No. 2, 247-252
"AIN Substrates with High The
In a paper entitled "rmal Conductivity", high-density, highly-purified aluminum nitride powder was sintered under pressure to obtain a thermal conductivity of 160 W / mK (room temperature) and an electrical resistivity of 5 × 10 ¹³ Ωcm.
(Room temperature), a dielectric constant of 8.9 (1 MHz), a flexural strength of 50 kg / mm ² , and a thermal expansion coefficient of 4.3 × 10 ⁻⁶ / ° C. (room temperature−400 ° C.). Also,

[2] Tokiko 58-1595
In No. 3, a thermal conductivity of 0.25 cal / cm · s · ° C or higher and a resistivity of 10 ⁷ Ω · cm
As described above (at room temperature), a substrate for an electrical device having a property of a thermal expansion coefficient of 4 × 10 ⁻⁶ / ° C. or less is disclosed. the above

[1]

[2] Non-oxide ceramic sintered bodies including aluminum nitride and silicon carbide
Utilizing these various characteristics is expected to contribute to improving the performance of electronic devices. Hybrid ICs are one of the leading fields of non-oxide ceramics applications.
Therefore, the development of a thick film composition necessary for forming the circuit has been advanced. In the hybrid IC substrate, it is first essential that a resistor is formed together with the conductor wiring in view of the circuit configuration. Conventionally,

[3] Japanese Patent Application Laid-Open No. 62-216301 discloses a resistive composition comprising a conductive powder, an inorganic binder, an organic vehicle and, if desired, a metal oxide additive, wherein the inorganic binder is SiO ₂ or Al _2. O ₃ , B ₂ O ₃ , CaO, ZnO and a crystalline glass frit containing TiO ₂ as a main component, preferably SiO 2
_{2 (28-42wt%) - Al 2} O 3 (10-22wt%) - B 2 O 3 (1-5w
t%) - CaO (14-25wt% ) - ZnO (15-25wt%) - TiO 2
(6-15 wt%) a glass frit,

[4] JP-A-63-136601 discloses a thick-film resistor in which a porous resistive film is provided on an aluminum nitride substrate. Here, in order to form a porous resistance film,
(1) When RuO ₂ is used as the conductive particles, SiO ₂ —Al ₂ O
_{3 -B 2 O 3 -CaO-ZnO} -TiO 2 -MgO system or _{SiO 2 -Al 2 O 3 -B 2} O
₃ -CaO-ZnO-TiO ₂ based crystalline glass frit, and (2) as the conductive particles with RuO ₂ when using the powder of Ag and Pb, using PbO-B ₂ O ₃ -SiO ₂ based amorphous glass frit I have.

[5] Proc. 5th International Microelec
tronics Conference, pp.137-141 (1988)
chnical progresses for a thick film resistor for a
aluminum nitride subsrates with devitrifiable solde
r glass ", SiO ₂ (10-16wt%)-
A RuO ₂ thick film resistor for aluminum nitride using B ₂ O ₃ (19-26 wt%)-ZnO (60-70 wt%) glass as a glass frit is disclosed.

[6] Mitsubishi Electric Technical Report, Vol. 54, No. 10, pp. 696-699 (1980
In the paper entitled "Hybrid IC igniter," a power transistor element and a circuit area for mounting a passive element for controlling the power transistor element were mounted on a separately divided alumina ceramic substrate, and an electric An electronic device for controlling an automobile engine is disclosed in which the communication is made by bonding a thin metal wire.

[7] The 1st Microelectronics Symposium Proceedings, pp.167-172 (1985)
In a paper entitled “VHF Band Power Amplification Module”, a thick-film wiring to configure a circuit was implemented by mounting a power transistor element and a passive element including a resistor to control it on a single aluminum nitride substrate. An electronic device for power amplification in a VHF band is disclosed.

[4] Ag as the conductive particles as in (b)
When the powder is used, the conductive network is likely to be destroyed by the migration of Ag. In this case, the stability during operation of the resistor is likely to be significantly impaired. Therefore, the conductive particles of the thick film resistor are preferably oxide-based.
In this regard,

[3],

(4) and

It is advantageous to use an oxide system as the conductive particles as in [5]. The common point of these prior arts is that crystalline glass is used as the inorganic binder and a porous resistance film is formed to easily release the gas generated by the reaction between the non-oxide ceramic and the inorganic binder. At least, it is to avoid foaming of the resistor and aggregation of the conductive particles.
Also,

[3],

(4) and

The case of [5] is common in that glass containing no lead oxide is used as the inorganic binder. this is,

As disclosed in [5], it is based on the finding that lead oxide-containing glass has high reactivity with non-oxide-based ceramics and easily generates gas. But,
According to the study of the present inventors, glass containing no lead oxide has extremely poor reactivity with non-oxide ceramics, and the adhesiveness between the ceramics and the resistor is easily impaired. It has been found difficult to stabilize. Specifically, the resistance value increases sequentially with the application of thermal stress during operation. This is due to the disconnection of the conductive network due to an increase in the micro crack of the resistor. The instability of such resistance characteristics is

[6] For car engine control,

[7] It is extremely fatal in electronic devices for power amplification in the VHF band, and while aluminum nitride has various excellent physical properties, the above-mentioned electronic devices have not been put to practical use or commercialized. I have. Therefore, the present invention compensates for the above-mentioned disadvantages of the prior art, and provides a non-oxide ceramic resistance composition which exhibits stable resistance characteristics even when a thermal stress is applied, and a non-oxide ceramic composition using the same. It is an object to provide a circuit board and an electronic device in which the circuit board is incorporated. [Means for Solving the Problems] The non-oxide ceramic resistance composition of the present invention is an aluminum nitride ceramic comprising a conductive substance, an inorganic binder, an organic vehicle, and optionally a metal oxide additive. Resistance composition, wherein the inorganic binder comprises 3 parts of lead oxide.
To 15 wt%, preferably a crystalline glass having a softening point of 600 ° C. or more and a thermal expansion coefficient of 4.0 × 10 ⁻⁶ / ° C. or less. SiO ₂ , B ₂ O
₃ and ZnO as main components, and one of MnO, WO ₃ , ZrO ₂ , Cr ₂ O ₃ and TiO ₂
It can include more than one species. In particular, SiO ₂ 15% or less, B ₂ O ₃ 15~30%, preferably ZnO50~80%, MnO or the like is preferably 5% or less. In the non-oxide ceramic circuit board of the present invention, a resistor comprising a conductive substance, an inorganic binder and, if desired, a metal oxide additive is provided on an aluminum nitride ceramics substrate. Basically, the agent is a crystalline glass containing 3 to 15% by weight of lead oxide. Electronic device of the present invention, a conductive substance, an inorganic binder,
If desired, a resistor comprising a metal oxide additive is provided on an aluminum nitride ceramics substrate, and the inorganic binder of the resistor is a crystalline glass containing 3 to 15% by weight of lead oxide. It is basically built into an electric circuit handling the above or an electric circuit having an element with power consumption of 0.2 W / mm ² or more. [Action] In the present invention, the crystalline glass containing lead oxide is
It contributes to dense and strong adhesion between the aluminum nitride substrate ceramic substrate and the resistor provided on the substrate. In order to realize strong adhesion with aluminum nitride ceramics, an appropriate reaction with glass, which is a main component of the resistor, is indispensable. As a result of various studies by the present inventors, the use of crystalline glass containing an appropriate amount of lead oxide as an inorganic binder can prevent (1) foaming of a resistor and aggregation of conductive particles, and (2) It was confirmed that strong adhesion with the aluminum nitride ceramics was realized, and (3) cutting of the conductive network was avoided, and a resistor having stable resistance characteristics was obtained. The resistor in the present invention is formed by the following mechanism. (A
-1) Lead oxide in the glass reacts with the aluminum nitride ceramic and wets its surface, forming a new glass layer contributing to the adhesion between the ceramic and the resistor,
(A-2) The further reaction is suppressed by the shielding effect of the new glass layer. (A-3) At this time, the gas slightly generated due to the formation of the new glass layer is caused by crystallization of the glass. (A-4) The crystallized glass released through fine pores has a low coefficient of thermal expansion by itself, and the coefficient of thermal expansion of a composite composed of conductive particles and glass is equivalent to that of aluminum nitride ceramics. Alternatively, it has a role of adjusting so as to be smaller. The main reason for realizing the above (1) is the mechanism of the above (a-2) and (a-3), and the main reason for realizing the above (2) is the above (a-
The main reason for realizing the mechanism (1) and the above (3) is based on the result of the mechanism (a-4) effectively acting. In the present invention, the inorganic binder comprises (a) 3 to 15 wt.
% Of lead oxide, (b) softening point: 600 ° C. or more and (c) coefficient of thermal expansion: 4.0 × 10 ⁻⁶ / ° C.
It is preferred to have: The reason that (a) is specified is that if the content of lead oxide is less than 3 wt%, the reaction of the glass with the aluminum nitride ceramics is insufficient,
It is difficult to form a new glass layer required to achieve strong adhesion, and if it exceeds 15 wt%, the reaction of the glass with the aluminum nitride ceramics is excessive, and the generation and release of gas due to the reaction are difficult to balance. Then, the generated glass layer has a shielding effect, which suppresses the release of gas, and tends to cause foaming of the resistor and aggregation of the conductive particles. (C) is specified because the softening point is 600 ° C
If the ratio is less than the above range, the softening and the flow of the glass are promoted, so that the reaction with the non-oxide-based ceramics is excessively performed, which causes another cause of foaming of the resistor and agglomeration of the conductive particles. Further, (c) is specified because the coefficient of thermal expansion is
If the temperature exceeds 4.0 × 10 ^-6 / ° C, tensile stress is applied to the glass and the characteristics are likely to be unstable.The thermal expansion coefficient of the resistor as a composite must be equal to or smaller than that of aluminum nitride ceramics. Due to difficulty. In the present invention, the thermal expansion coefficient equivalent to aluminum nitride ceramics means the following. α _R = (α _C ± 1) × 10 ⁻⁶ (° C. ⁻¹ ) where α _R : coefficient of thermal expansion of resistor α _C : coefficient of thermal expansion of aluminum nitride ceramics This is because it is extremely difficult to avoid an increase in micro cracks due to the application of thermal stress. [Embodiment] [Embodiment 1] In this embodiment, a power element and a control board for controlling the power element are mounted on the same board, and an electronic device using the circuit, that is, an igniter module device, and the like. A distribution device to which an electronic device is applied will be described. In obtaining circuit boards and equipment,
RuO ₂ powder (average particle size 0.1 μm), glass powder (average particle size 0.2 μm) as an inorganic binder, and a resistance composition containing ethyl cellulose resin as an organic vehicle and α-terpineol as basic components It was produced by kneading with this roll. The crystalline glass powder used here is
_{PbO (6wt%) - SiO 2} (9wt%) - B 2 O 3 (20wt%) - ZnO
(60wt%) - MnO (2wt %) - WO 3 (2wt%) made in the composition,
It has a thermal expansion coefficient of 3.5 × 10 ^-6 / ° C alone and a softening point of 61
Has 0 ° C. The organic vehicle is added in an amount of about 25% by weight in the composition. FIG. 1 shows the relationship between the [RuO ₂ powder / (RuO ₂ powder + glass powder)] weight ratio, the resistance value, and the thermal expansion coefficient of a resistor obtained by baking the above composition in air at 850 ° C. for 10 minutes. is there. The resistance value decreases as the weight ratio increases, and the thermal expansion coefficient increases as the weight ratio increases. Weight ratio 0.2-0.8
The resistance value is adjusted in the range of 10Ω / □ -1MΩ / □ between
The coefficient of thermal expansion is adjusted in the range of 3.8-5.5 × 10 ⁻⁶ / ° C. Fig. 2 shows the resistance value and temperature coefficient of resistance (TCR) of the resistor.
The relationship is The curve A in the same figure shows the case where the metal oxide for adjusting the TCR was not added, and the curve B shows the case where the MnO ₂ powder for adjusting the TCR was added.
The curve A shows a large value at a resistance value of about 2 kΩ / □ or less, which has a practical problem. On the other hand, curve B
Has a small TCR of ± 200 ppm / ° C., which is practically no problem even in a low resistance region of 2 kΩ / □ or less. This is T
This is due to the effect of adding MnO ₂ for CR adjustment.
Alternatives to MnO ₂ include copper oxide, manganese oxide, lanthanum oxide, neodymium oxide, niobium oxide, vanadium oxide, titanium oxide, zirconium oxide, antimony oxide,
Examples include samarium oxide, praseodymium oxide, aluminum oxide, chromium oxide, iron oxide, cobalt oxide, tantalum oxide, nickel oxide, and silicon oxide. Ethyl cellulose resin and α-terpineol as organic vehicles are replaced by aliphatic alcohols, esters of such alcohols such as acetates and propionates, terpenes such as pine oil, β-terpineol, ethylene glycol, monoacetate, polymethacrylate, etc. it can. FIG. 3 shows a circuit board 10 manufactured using the above-described resistance composition.
It is. Metal layer (silver-palladium,
A region 101 (thickness 13 μm) and a wiring metal layer (silver-palladium, 13 μm) region 111 for forming a power element control circuit are provided on the aluminum nitride sintered substrate 100. ) 100-750Ω). region
101 has a transistor chip (5 × 5) as a power element.
mm, 5W, 15A) 103 is Pb-5wt% Sn-1.5wt% Ag solder 104
(Not shown), six are mounted in parallel. Overcoat glass 113B (not shown) is provided on required portions on the wiring metal layer region 111 and the resistor 113A, and the chip capacitor 113C and the mini-mold transistor 113d are connected to Pb-
5 wt% Sn-1.5 wt% Ag solder 114 (not shown) is provided. The metal layer regions 101 and 111 and the transistor chip 103 and the metal layer region 111 are connected by a thin aluminum wire (having a diameter of 350 μm) 105. A metal layer (silver-palladium, 13 μm in thickness) 121 is also provided on almost the entire surface of the aluminum nitride substrate 100 on which the elements are not mounted. (Having the same quality as glass 113B). The metal layer regions 101 and 111, the metal layer 121 and the resistor 113A are formed at 850 ° C. and 10 m
in-air sintering.
3B and 123 were obtained by calcination in air at 600 ° C. for 10 minutes.
The substrate 100 used was obtained by sintering aluminum nitride powder together with a trace amount of Y ₂ O ₃ powder at 1700 ° C. under normal pressure. It is a sintered body (thickness 0.8 mm, thermal conductivity 170 W / m · K, resistivity 10 ¹³ Ω · cm or more). FIG. 4 (a) shows each of the resistors 113A from -55 to 150
It is an example which shows transition of the resistance value by a temperature cycle test of 1000 degreeC (1000 times) and a high temperature storage test of 150 degreeC (1000h). In any of the tests, the resistance value is within ± 0.5% of the initial value and has a practically satisfactory stability. Such stable characteristics were obtained because of the mechanism (a-1)-
Based on the result of (a-4) acting effectively. In addition, although power 7 times the rated power was repeatedly applied to the resistor 113A by intermittent energization, the change in resistance value was within ± 0.5% even after 90,000 intermittent energizations, and no practical problem was found. . This is, of course, based on the functions of (a-1)-(a-4). In addition, heat dissipation through the aluminum nitride substrate 100 is effectively performed, and the temperature rise of the resistor 113A is slightly suppressed. Therefore, the destruction of the conductive network due to the application of an electric field at a high temperature could be avoided. Further, FIG. 4 (b)
Is an example showing a change in the resistance value of the resistor 113A in a high-temperature high-humidity test (1000 hours) at 80 ° C. and 90% RH. In this test, a sample in which the overcoat glass 113B was not provided on the resistor 113A was used. The resistance value remains within ± 0.5% even after the test, and there is no practical problem. Note that the metal layer regions 101 and 111 have silver-metal as a metal component.
Lead oxide-containing glass frit (SiO ₂₎ for maintaining the adhesion between palladium and the aluminum nitride sintered body substrate 100
_{(14.8wt%) - Al 2 O} 3 (1.5wt%) - PbO (69.4wt%) - B
₂ O ₃ (2.1 wt%)-ZnO (17.8 wt%)]. The amount of the glass frit is adjusted to suppress an excessive reaction. The resistance composition used in this example has excellent compatibility with the metal layers 101 and 111, and no defects such as bubbles are generated at the contact portion between the resistor 113A and the metal layer 111. In FIG. 5, reference numeral 200 denotes an igniter module device for controlling an automobile engine as an electronic device, and a circuit board.
10 is a package with nickel-plated aluminum
It is mounted on 201 via a solder (Pb-60 wt% Sn) 202. This soldering was carried out through a belt furnace at 240 ° C. with the above-mentioned solder sheet interposed with the flux. Next, a silicone resin (not shown) was charged into the package 201 and cured, and then a cap 203 was attached to complete the module device 200 having the circuit configuration shown in FIG. Transistor chip 103 and package 201 of the device 200
The thermal resistance between them was as low as 0.9 ° C / W. Further, a temperature cycle of −55 to 150 ° C. was applied 2,000 times to the device 200, and a temperature cycle of 50 to 125 ° C. was applied 90,000 times to the transistor chip 103 by intermittent energization, respectively. Never Further, the transistor chip 103
And its control circuit are provided close to each other on the same substrate 100, and a module device that is reduced in size to about 3/5 as compared with a conventional device in which the power element unit and the control circuit are provided on separate substrates is provided. Obtained. Note that the module device 200 was mounted on a housing together with other circuit devices, and a distribution device device capable of guaranteeing the specifications shown in Table 1 was completed. 7 (a) and 7 (b) are diagrams showing the relationship between the output voltage and input current of the device and the rotation speed of the distributor. The output voltage of the power distribution device (curve A) obtained in this embodiment is lower than that of the power distribution device (curve B) incorporating the conventional module device in which the power element unit and the control circuit are provided on separate substrates. A high value is obtained in the rotation speed range and under a small input current. Further, in the idle rotation region, a high output voltage is obtained under an input current smaller than that of the conventional device. This indicates that in the power distribution device of this embodiment, it is possible to suppress power consumption in the low-speed rotation range and obtain a sufficient coil cutoff current in the high-speed rotation range. FIG. 7 (b) shows the relationship between the closing ratio of the device and the rotational speed of the distributor. This closing ratio control is an important factor in suppressing power consumption in a low speed rotation range and obtaining a sufficient coil cutoff current in a high speed rotation range. The figure shows the case where the battery voltage is used as a parameter, but shows that the closing ratio control is optimally performed even with respect to the fluctuation of the power supply voltage. Although the distribution device was mounted in the engine room where the temperature of the mounting portion became 80 ° C., the closing ratio was controlled well. In this embodiment, a power element having a power consumption of 0.2 W per unit area (1 mm ² ) is mounted on the circuit board.
The performance of the distribution device shown in the table was obtained. Equivalent performance was obtained even when the chip size of the power element was reduced, that is, when a power element with a power consumption of 0.56 W per unit area (1 mm ² ) was mounted on the circuit board. [Embodiment 2] In this embodiment, a power element and a circuit board on which a control circuit for controlling the power element are mounted on the same board, an electronic device using the circuit, that is, a high-frequency voltage amplifier circuit device, and the electronic device are described. An applied high definition television device will be described. FIG. 8 is a cross-sectional view of a main part of a circuit board which enables a power element and its control circuit to be mounted on the same board.
As shown in FIG. 1, a circuit board 10 includes a power element mounting portion metal layer (silver-palladium, 13 μm thick) region 101 and a power element control circuit forming metal layer (silver-palladium, 13 μm).
m) The region 111 is mounted on the aluminum nitride sintered body substrate 100. In the region 101, a field effect transistor chip (2 × 2 mm, 5w, 15A) 103 as a power element is Pb-5 wt%.
The area 111 is provided with a resistor 113A and an overcoat glass 113B by printing and baking a thick film paste, and a chip capacitor 113C and a diode chip 113d are mounted on the area 111. Pb-5wt% S
It is provided by n-1.5 wt% Ag solder 114 (not shown). A thin gold wire ((35 μm in diameter) is provided between the metal layer regions 101 and 111 and between the transistor chip 103 and the metal layer region 111.
m) connected by 105. A metal layer (silver-palladium, 13 μm in thickness) 121 is also provided on almost the entire surface of the aluminum nitride sintered body 100 on which the elements are not mounted, except for a region substantially corresponding to the portion where the transistor chip 103 is mounted. Is provided with glass 123 (same quality as glass 113B). The circuit board 10 was manufactured in the same manner as in Example 1, but the difference from Example 1 was that an inorganic binder was used.
_{PbO (6wt%) - SiO 2} (9wt%) - B 2 O 3 (20wt%) - ZnO
(60wt%) - MnO (2wt %) - WO 3 PbO (60wt%) as a crystalline glass (2 wt%) having a composition _{- SiO 2 (8wt%) -} B 2 O 3
(12wt%) - ZnO (10wt %) - ZrO 2 (8wt%) - Cr 2 O 3 (2
(wt%) is a resistance composition using a powder (particle size: 2.0 μm) obtained by mixing amorphous glass having a composition of 3: 1 by weight. The same temperature cycle test (1000 times), high temperature standing test (1000 h), and high temperature and humidity test (1
000h), and an intermittent energization test (90,000 times) was performed. In each of the tests, the resistance value was within ± 0.5% of the initial value and was stable without any practical problem. Such resistance value stabilizing characteristics were obtained because of the above-mentioned mechanism (a-1)-
This is nothing but the result of (a-4) acting effectively. Furthermore,
The porous part of the resistor is filled by the flow of the amorphous glass (voids disappear), and the mass transfer due to the electric field concentration in the voids and the destruction of the conductive network are avoided, which also contributes to the above stability. doing. In the same manner as in the first embodiment, the circuit board 10 is soldered (Pb
-60 wt% Sn) 202. This soldering is performed by interposing the above solder sheet together with the flux.
The test was performed through a belt furnace at 0 ° C. Then package 2
After filling and curing the silicone resin in 01, the cap 203 was attached to complete the high-frequency voltage amplifier circuit device 200. FIG. 9 shows an input voltage waveform and an output voltage waveform of the device 200. As is clear from this, the output voltage is 35 V, which is 50 times the value of 0.7 V of the input voltage, and the output voltage waveform also shows a time constant of 0.2 ns or less for both rising and falling. That is, the device 200 is sufficiently practicable for controlling a high frequency voltage in the 250 MHz band. The first reason that the device 200 can follow such a high-speed signal is that the electrical connections between the transistor chip 103 and its peripheral circuits and the control circuit wiring are reduced as much as possible. In particular, the fact that the electrical communication path could be shortened was to form a thick-film resistor that could be used for non-oxide ceramics,
This is because the size of the resistor can be reduced based on the efficient heat dissipation as the ripple effect. By adjusting the circuit constant, specifically, the resistance of the resistor 113A, the above device 200 is used to adjust the frequency from 50 MHz to 1 GHz.
Although high-frequency voltage control was attempted up to this point, it was confirmed that it had sufficiently practical amplification characteristics. The high-frequency voltage amplification circuit device 200
Built into a 0x2000 television device. As a result,
It was confirmed that the above-described device 200 was effective for high definition image display. In the circuit board and the electronic device of the present invention, the power element and the element for the control circuit are mounted on the same substrate, and the effect is maximized. However, the present invention is not limited only to this case, and the power element may not be mounted. The electronic device according to the invention is applied to, for example, the igniter module device 200 according to the first embodiment, the high-frequency voltage amplifier circuit device 200 according to the second embodiment, the distribution device device according to the first embodiment, and the television device according to the second embodiment. [Effects of the Invention] According to the present invention, a resistance composition for non-oxide ceramics, which exhibits stable resistance characteristics even when a thermal stress is applied, a non-oxide ceramic circuit board using the same, and a non-oxide ceramic circuit board using the same A high-performance and high-reliability electronic device incorporating a circuit board is obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between the resistance value and the amount of RuO ₂ in the resistor, FIG. 2 is a diagram showing the relationship between the TCR and the resistance value, and FIG. 3 uses the circuit board according to the present invention. 4 (a) and 4 (b) are diagrams showing the relationship between the change in resistance value and the number of temperature cycles or high-temperature leaving time, and FIG. 5 is a sectional view of the electronic device according to the present invention. FIG. 6 is an electric circuit diagram of FIG. 5,
FIGS. 7 (a), (b) and (c) are diagrams showing the relationship between the distributor rotation speed and the output voltage, input current and closing ratio in the apparatus shown in FIG. 5, and FIG. FIG. 9 is a cross-sectional view of an electronic device having a control circuit, and FIG. 9 is a graph showing input voltage and output voltage waveforms. 10 ... circuit board, 100 ... sintered board, 103 ... transistor chip, 111 ... wiring metal layer, 113 ... resistor.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tsuneo Endo 190 Kashiwagi Kashiwagi, Komoro City, Nagano Prefecture Komoro Plant, Hitachi, Ltd. (56) References JP-A-60-137847 (JP, A)

Claims (3)

(57) [Claims] 1. A resistance composition for aluminum nitride ceramics comprising a conductive material, an inorganic binder, an organic vehicle, and, if desired, a metal oxide additive, wherein the inorganic binder contains 3 to 4 lead oxides. ZnO-B ₂ O ₃ -SiO containing 15 wt%
_2. A resistive composition comprising a crystalline glass containing ₂ as a main component. 2. A resistor comprising a conductive substance, an inorganic binder and, if desired, a metal oxide additive is provided on an aluminum nitride ceramics substrate, wherein said inorganic binder contains 3 to 15 wt% of lead oxide. circuit board, wherein the ZnO-B ₂ O ₃ -SiO ₂ is a crystalline glass whose main component is. 3. A resistor comprising a conductive substance, an inorganic binder and, if desired, a metal oxide additive is provided on an aluminum nitride ceramic substrate, wherein said inorganic binder contains 3 to 15% by weight of lead oxide. the ZnO-B ₂ O ₃ -SiO ₂ on a circuit board is a crystal glass as a main component, the power consumption of ² per frequency 50MHz or more electrical circuits or 1mm is an electric circuit including a semiconductor element is not less than 0.2W mounted to An electronic device characterized by being performed.