JPS61292402A - Microwave integrated circuit - Google Patents

Abstract

PURPOSE:To attain low cost by using copper being an inexpensive base metal as a conductor layer and using a glaze made of a silicate and a non-reducing glass being inexpensive and hardly reduced in place of a ruthenium oxide (RuO2) as a resistor. CONSTITUTION:A thin aluminum plate substrate whose surface is smooth is used as a ceramic substrate 10. Copper paste being copper with a trace of additives is printed on the entire one face of the substrate by using a screen with a specific mesh, dried for 10min with a drier at 125 deg.C to obtain a ground conductor layer 20. The same copper paste is printed and dried on the other face to obtain wiring conductor layers 21-25. The semi-product is given in an atmospheric thick film belt furnace and baked under a temperature pattern of peak temperature of 900 deg.C for 10min under nitrogen atmosphere. Then the glaze resistor films 50, 51 are obtained by kneading sufficiently the solid content and the vihicle shown in table I to form resistance paste, printing and drying with a screen under specific mesh and emulsion thickness, baking the paste with the same condition as the copper conductor layer.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to integrated circuits used in the microwave band.

BACKGROUND OF THE INVENTION In recent years, with the advancement of information and the increase in the amount of information, communication frequencies have become higher, and practical use has begun in the microwave band, such as in the reception of Saisei Broadcasting. For circuit units such as transmitters and receivers used in the microwave range, microwave integrated circuits (hereinafter referred to as MICs), which are integrated with a thick-film hybrid circuit structure, have become mainstream due to their miniaturization and cost reduction. It's coming.

The conventional microwave integrated circuit described above will be described below with reference to the drawings.

FIG. 2 shows transistor TR, strip line Lj+
L21 L5 *This shows a drain-grounded microwave oscillation circuit consisting of resistors R1 to R6 + capacitance C9 dielectric resonator DR. Figure 3 shows a cross-sectional view of the structure when this oscillation circuit is formed using MIC using thick film technology. Shown below.

Conventional thick film MICs are made of ceramic substrates such as alumina1.
A conductor paste consisting of a noble metal conductor such as silver, silver-platinum, or gold is screen printed on
The ground conductor layer 30 and wiring conductor layers 31 to 36 are formed by baking at a temperature of 0.00"C. Next, resistors such as DC bias resistance ("l + "2) + termination resistance R3, attenuator resistance R4 to R6, etc. As an element, ruthenium oxide R
u02-Glass-based glaze resistor paste is applied to the conductor layer 31.
, 32 and 33, and baked at a temperature of 750° C. to 900° C. in air to form a glazed resistive film 60° 61, and trim the resistor as necessary.

Thereafter, chip components such as the dielectric resonator DR, capacitor chip C1, and transistor chip TH are mounted by soldering, etc., and wires are connected using wires 4o for wire bonding to complete the structure.

(For example, ``Thick film MIC SHF TV terrestrial broadcasting receiving converter,'' 1978, National Conference of the Television Society,
13-17. (Ueno et al.) Problems to be Solved by the Invention Conventional MICs as described above have a small size, high performance, and are easy to produce. It cannot be said that it is cheap because it is used frequently. Copper (Cu) can be considered as another inexpensive conductor material that does not increase the conductor loss of one wiring, but since copper is easily oxidized, it is impossible to form a conductor in air. Conversely, even if Cu is formed in nitrogen, a resistor cannot be formed in nitrogen because the ruthenium oxide RuO2 of the resistor is easily reduced. As described above, conventional MICs have a fatal drawback in that the materials used are expensive, making it difficult to reduce costs and also difficult to replace with cheaper materials.

In view of the above-mentioned problems, the present invention provides an inexpensive and high-performance MMC constructed from inexpensive wiring materials and resistance materials.

Means for Solving the Problems In order to solve the above problems, the MIC of the present invention is composed of at least a conductor layer made of copper and a silicide-non-reducible glass glaze resistor.

Operation The present invention has the above-described structure, uses copper, which is an inexpensive base metal, for the conductor layer, and uses a glaze made of an inexpensive and resistant to reduction silicide and non-reducible glass instead of RuO2 as a resistor. This makes it possible to realize an inexpensive MIC with circuit performance equivalent to or better than that of the conventional one.

EXAMPLE An example of the present invention will be described below with reference to FIG. In FIG. 1, the conductor layers 20 to 26 are made of copper, and the glazed resistive films 60 and 51 are composed of a silicide-non-reducible glass glazed resistor, but the other components are as shown in FIG. 3
Same as the figure. In addition, the actual row has the same structure as the conventional row (
The experiment was conducted on a microwave oscillation circuit with the same pattern shape.

As the ceramic substrate 1o, the alumina content is 98%,
An alumina substrate with a thickness of O, El n and a smooth surface on a 2Off angle thin plate was used.

A copper paste containing a small amount of additives is printed on the entire surface of one side of this board using a 325 mesh screen.1.1
Dry in a dryer at 25°C for 10 minutes, and remove the ground conductor layer 2o.
I got it.

Next, the same steel paste was printed and dried on the other side to obtain wiring conductor layers 21 to 25. This means that the oxygen concentration in the furnace is 109 pl! It was fired in a nitrogen atmosphere with a peak temperature of 900''C and a temperature pattern held for 10 minutes through an atmospheric thick film belt furnace.
When we investigated the electrical characteristics of the IJ tube line, we found that the conductor thickness was 1e to 18μm and the conductor resistance (DC) was 2mQ10.
The conductor loss at 6 GHz was about o, osda.

Next, a resistance paste prepared by thoroughly kneading the solid components shown in Table 1 and the vehicle was printed on a 250-mesh screen with a milk thickness of 20 μm, dried, and fired under the same conditions as the copper conductor layer. It was set to ゜22. After this, each resistor R1 to R6 is adjusted to the required resistance value by laser trimming, and each chip component C,, TR, DR is attached to M.
Completed IC.

(Left space below) Table 2 shows a comparison of typical characteristics of the microwave oscillation circuit of the present invention thus obtained with those of a conventional MIC oscillation circuit. As can be seen from the table, the reason why the MIC of the present invention has superior characteristics compared to conventional MICs is that low-resistance copper is used as the wiring material, and a thick film resistive material that is compatible with this is formed. This is due to the configuration. In addition, compared to conventional MUG and MU conductors, the MIC of the present invention does not show any deterioration in adhesion due to solder cracks or deterioration in conductor properties due to migration, so it is extremely easy to manufacture. It has become a thing.

Table 2 Effects of the Invention As described above, the present invention is achieved by configuring a conductor layer made of at least copper on a ceramic substrate and a silicide-non-reducible glass glaze resistor in contact with the conductor layer. It is possible to provide a microwave integrated circuit that is inexpensive, easy to manufacture, and has excellent characteristics, which is extremely important in industry.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing the structure of a part of the microwave integrated circuit of the present invention, Fig. 2 is a drawing showing a microwave oscillation circuit, and Fig. 3 is a diagram showing the structure of part of the conventional microwave integrated circuit. FIG. 10... Ceramic substrate, 20.30...
...Ground conductor layer, 21-25.31-35...
Wiring conductor layer, 40...Wire, 50, 51.
60.61...Glaze resistance film.

Claims (1)

[Claims] At least on a substrate made of electrically insulating ceramic,
1. A microwave integrated circuit comprising: a conductor layer made of copper; and a silicide-non-reducible glass glaze resistor layer electrically in contact with the conductor layer.