JPS5873146A - Hybrid integrated circuit and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a small-sized hybrid integrated circuit with a highly precise and stabilized resistor and a conductor having high connecting strength by a method wherein a glass intermediate layer is formed between a high dielectric constant substrate and a thick film resistor with a conductor. CONSTITUTION:A glass layer 4 is provided on the high dielectric constant substrate 1, consisting of rutile type or probeskite type dielectric grains 9 such as ZrTiO4, CaTiO3 and the like, a distribution constant line 2, conductors 4 and 5, a thick film resistor 6, an active element 4, and a capacitor 7 are provided, and an earth conductor 2' is attached to the back side of the glass layer 14. The glass 14 on the dielectric particles 9 is infiltrated into the substrate by sintering. The thick film resistor consists of the conductive material praticles 10 of ruthenium such as RuO2 and the like which was connected by the glass binder 11 having Pb, Si, Ca and the like as main components. Because there exists the glass layer 14 below the binder 11, the infiltration and diffusion into lower part is a little, and the particles 10 are connected moderately. Besides, the sintering of the thick film or the conductor is to be performed at the temperature lower than that of the transition or crystallization of glass. According to this constitution, the obtained resistors have excellent accuracy and stability, and a small-sized hybrid IC of high adhesive strength can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a structure of a microwave hybrid integrated circuit and a method of manufacturing the same.

Conventionally, UHF@ electric circuits were composed of active elements such as coils, capacitors, and transistors, but in order to improve accuracy, eliminate adjustment processes, and make them thinner, it was necessary to flatten or distribute the resonant circuit etc. A constant line is desired.

For example, when a band amplifier is configured with a distributed constant circuit, the size of the distributed constant line is IGH if an alumina substrate (dielectric constant ε 9), which is commonly used in hybrid integrated circuits, is used.
As is clear from Table 1, for the Z band amplifier, one side is 5.
The size is 106n, which is not practical. Therefore, if a high dielectric constant substrate (ε>1o) is used, 1. As shown in Table 1, for example, when ε is 36, it is about 6 crn angle, and when ε is 100, it is about 2 crn angle.
This is the size of the rn angle, which is the size of a practical hybrid integrated circuit.

(Table 1 on white page, bottom 41) Substrate dielectric constant and wavelength (1Qflz) Figure 1 is a cross-sectional schematic diagram of a hybrid integrated circuit using this high dielectric constant substrate. A distributed constant line conductor 2° and bonding component mounting conductors 4 and 5 are formed on a substrate 1, and a resistor 6 is further formed.On this wiring substrate, an active element 6 such as a transistor, and a component 7 such as a chip capacitor are soldered. At step 8, the component mounting conductor 4.5 is connected and mounted to complete the hybrid integrated circuit.By the way, when a thick film resistor is formed on a high dielectric constant substrate, as shown in FIG.
The sheet resistance value is several times higher than that when formed on a normal alumina substrate, and its variation and change over time are also large.

Figure 6(a) shows a schematic cross-sectional view of a thick film resistor formed on a high dielectric constant substrate.
4, RIJO21Bi2R on nortyl type or bevlovskite type dielectric grains 9 such as MgTiO31CaTiO3
A ruthenium-based conductive material 10 such as uO7+PbzRu20s is attached, and the conductive material and the substrate dielectric material are bonded to a thick film resistor glass binder 11 whose main component is Pb+bi+Ca9Mg or the like.

It is said that in the thick film resistor, the glass conductive material particles 10 are appropriately connected to obtain a desired sheet resistance value. The reason why the resistance value of a thick film resistor on a high dielectric constant substrate is large is that the resistance value of a thick film resistor on a high dielectric constant substrate is higher than that when it is formed on a normal alumina substrate, as shown in Fig. 3(b). It is presumed that the glass distribution 16 in the above is because -1- penetrates between the grain boundaries of the ppm body, and appropriate connection between the resistive conductive particles is not achieved.

Although the above explanation was made using a resistor, the adhesive strength of a thick film conductor formed on a high-n conductivity substrate is also a few orders of magnitude lower than that of a thick film conductor formed on an alumina substrate. The reason for this is also presumed to be excessive penetration of the binder glass component into the substrate.

The purpose of the present invention is to eliminate the drawbacks of conventional hybrid integrated circuits using high dielectric constant substrates as described above, and to improve accuracy.

Another object of the present invention is to provide a small microwave hybrid integrated circuit having a resistor with high stability and a conductor with high connection strength, and a method for manufacturing the same.

For this purpose, a high dielectric constant substrate and a thick film resistor are used.

An intermediate layer of glass is formed between the conductors.

The present invention will be explained in detail below using specific examples. ○ Fig. 4 is a schematic cross-sectional view of one embodiment of the present invention, in which a distributed constant line conductor 2. Conductors 4, 5, and thick film resistor 6 with bonding components mounted
Active elements 4 such as transistors and components 7 such as chip capacitors are mounted on a wiring board with a ground conductor 2' formed on the back surface. FIG. 5 (&) is a schematic diagram of the cross section of the thick film resistor and high dielectric constant substrate of this example, and the crow 14 formed on the vI electric particles 9 is inside the high dielectric constant substrate by firing. However, in the resistor formed on this glaze layer, the resistor glass binder 11 that connects the ruthenium-based conductive material 10 and the substrate penetrates into the lower part because there is a glaze layer below.・There is little diffusion and maintains an appropriate connection between conductive materials.

As described above, in the hybrid integrated circuit board shown in the embodiment, the glass layer 14 and the resistor 6 must be fired separately. If simultaneous firing is performed, the mutual diffusion of the glass component 11 in the glass + 414 resistor will be large, resulting in a value that is significantly different from the original sheet resistance value (value on the alumina substrate), and the variation thereof is also large.

Furthermore, the firing temperature TfR of the resistor 6 and the glaze layer glass 1
Examining the relationship between the softening temperature T8 and the crystallization temperature Tc of No. 4, as shown in Table 2, if Tc>TfH, the variation in resistance value is small. When amorphous glass is used, the glass transition temperature Tg must naturally be Tgn1'fR. When amorphous glass and crystallized glass are compared as a glaze layer, the resistance fluctuation value of crystallized glass is smaller.

From the above, the most suitable glass paste for the glaze layer is a crystallized glass paste whose crystallization temperature Tc is higher than the firing temperature TfR of the resistor.

In this case, the firing temperature of the glaze layer needs to be higher than Tc. The optimum paste shown in Table 2 is St.
, Ca, Mgl, Al, Zr, and B as main constituent elements.

Table 2 Compatibility of Glaze Layer Glass Paste and Resistance When using this glass paste and using a ruthenium-based resistor fired at 850°C, the initial sheet resistance value will be the original sheet resistance value (when formed on an alumina substrate). ) compared to 0
This value is 7 to 1.1 times higher than that of the original sheet resistance value, which is much closer to the original sheet resistance than when a resistor is formed directly on a high dielectric constant substrate, and the variation thereof is also small.

Further, the change over time was 0.6% when left at 150°C for 000 hours, which is much more stable than when formed directly on a high dielectric constant substrate, and the same as when formed directly on an alumina substrate. Of course, if a resistive overcoat glass is applied, the variation will be 0.1%.

Also, in the conductor, since there is a suitable amount of binder glass between the conductor particles and the glaze layer, the connection strength is several times greater than that when the conductor is formed directly on a high dielectric constant substrate.

The dielectric constant ε of the glaze layer is usually 10 to 15, which is smaller than the dielectric constant of the high dielectric constant substrate, but its thickness is usually 5 to 15.
~50 μm, which is smaller than the normal substrate thickness of 06 to 51K, so it hardly affects the wavelength shortening rate, that is, miniaturization.

Furthermore, the glaze layer may be omitted in portions that do not require much connection strength, such as distributed constant line portions, active elements, and small component mounting portions.

As mentioned above, a high dielectric constant substrate can be used by creating a hybrid integrated circuit structure in which a glass layer is formed on a rutile type or provskite type high dielectric constant substrate, and a resistor and a conductor are formed on it. It is possible to obtain a highly reliable small microwave hybrid integrated circuit with good resistance accuracy and stability and high conductor connection strength without losing the features of the wavelength shortened microwave hybrid integrated circuit such as small size and no adjustment. .

[Brief explanation of the drawing]

Figure 1 shows a schematic cross-sectional view of a high-permittivity substrate and a thick-film resistor section, and Figures 1-2 show an embodiment of the present invention for hybrid integration using a high-permittivity substrate. A schematic cross-sectional view of the circuit is shown in FIG. 6, which is an example A in which a glaze layer is provided between a high dielectric constant substrate and a thick film resistor. Type 704, ″1゛
−・−−su”− and ゛ −
1... High dielectric constant substrate 2.4.5... Thick film conductor 6... Thick film resistor 11... Thick film paste binder glass 14... Glaze layer glass "J-TOSE\1岨" t1 No. 37 Sword Bushe Min. 4th diagram 荊S diagram

Claims (1)

[Claims] 1. A hybrid integration characterized in that a circuit is provided with a thick film conductor and a thick film resistor on a substrate having a glaze layer on part or all of a high dielectric constant substrate. circuit. 2. The hybrid assembly according to claim 1, wherein the glaze layer is made of glass, and its glass transition temperature or crystallization temperature is higher than the firing temperature of the thick film conductor or resistor. circuit. 3. When manufacturing a hybrid integrated circuit by providing a glaze layer on part or all of a high dielectric constant substrate and providing a thick film conductor and a thick film resistor on this substrate, the resistor is baked at a temperature lower than the firing temperature of the glaze layer. A method for manufacturing a hybrid integrated circuit, which comprises firing.