JPS6211257A - Microwave integrated circuit - Google Patents

Abstract

PURPOSE:To form two or more of capacitances or a capacitance corresponding to the capacitances onto an area corresponding to one microwave integrated circuit by alternately superposing five layers or more of metallic thin-films and insulating films onto a dielectric substrate. CONSTITUTION:Metallic thin-films 12 and insulating films 13 are superposed alternately onto a dielectric substrate 11, the insulating films 13 are held among three layers of the metallic films 12, thus shaping two independent capacitances or a capacitance having twice capacitances in the same area. Accordingly, multilayers of MIM structure are stacked, thus increasing the capacitances per unit area or electrostatic capacitances.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a microwave integrated circuit that can be used for microwave amplification, oscillation, etc.

BACKGROUND OF THE INVENTION In recent years, as the use of microwave bands has become more active, solid-state microwave monolithic integrated circuits (MMrCs) have been rapidly developed. An MMIC has an active element and a passive element formed on the same substrate (monolithically). Among passive elements, a capacitance in which one layer of insulator is sandwiched between two layers of metal thin films (MIM structure) is often used. As a conventional technique, for example, MrM capacitance such as Hiroshi Miyauchi, Hiroshi Yamamoto, "Communication Microwave Circuit J (1981) Institute of Electronics and Communication Engineers, P2O" is available.

Such a conventional microwave integrated circuit will be explained using FIG. 3. Figure 3 is a cross-sectional view of the MIM capacitance of a conventional microwave integrated circuit, where 1 is a dielectric substrate, 2
3 is a metal thin film, and 3 is an insulating film. This circuit functions as a capacitor with both ends of the metal thin film 2 serving as electrodes.

However, in the above conventional configuration, when there are multiple capacitors with large capacitances on the same dielectric substrate,
The area becomes huge, and the area of the MMIC substrate largely depends on the area occupied by the capacitance.

The present invention solves the above-mentioned conventional drawbacks, and aims to provide a microwave integrated circuit in which the area of the capacitance can be reduced.

Means for Solving the Problems In order to solve the above problems, the microwave integrated circuit of the present invention has a total of five or more layers of metal thin films and insulating films alternately formed on a dielectric substrate.

Effect: According to the above configuration, two or more capacitances or equivalent capacitances can be formed in the area of one capacitance.

EXAMPLE Hereinafter, an example of the present invention will be described based on FIGS. 1 and 2.

FIG. 1 is a cross-sectional view of the capacitance of a microwave integrated circuit in a first embodiment of the present invention, in which 11 is a dielectric substrate;
12 is a metal thin film, 13 is an insulator, and metal thin yA12
is formed in three layers, and an insulating film 13 is sandwiched between each layer.

This capacitance operates as two independent capacitances, or a capacitance with twice the capacitance in the same area.

As described above, according to this embodiment, by forming the MIM structure into multiple layers, it is possible to obtain a large capacitance per unit area.

Note that in the first embodiment, the total number of layers of the metal thin film 12 and the insulating film 13 is five, but it may be seven or more layers. Further, although the substrate is made of a dielectric material, any material may be used as long as it is not a conductor.

FIG. 2 (A) is a perspective view of a microwave integrated circuit according to a second embodiment of the present invention, and FIG. Size 500x Son μrd Au vapor @ thin film, 23 is Cv
2000A no Si02 film formed by D.
4 is an Au wire with a diameter of 25 μm. The first and third Au vapor deposited thin films 22 are connected to other circuit elements on the same substrate, and the second Au vapor deposited thin film is grounded through an Au wire 24.

The microwave integrated circuit of this second embodiment operates as two independent capacitors.

As described above, according to this embodiment, by forming the MIM structure into multiple layers, a plurality of capacitances can be obtained in an area corresponding to one capacitance.

In the second embodiment, semi-insulating Ga is used as the substrate.
Although an As substrate was used, other semiconductor substrates may be used. In addition, Au is used as the metal i1 film, and 5tO2 is used as the insulator.
was used, but it goes without saying that other metals or insulators may be used.

Effects of the Invention As described above, according to the present invention, the number of capacitances or capacitance per unit area can be increased by making the MIMIM structure multi-layered, and its industrial utility value is extremely large.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a microwave integrated circuit according to an embodiment of the present invention, FIG. 2(A) is a perspective view of a microwave integrated circuit according to a second embodiment of the present invention, and FIG. The configuration diagram, FIG. 3, is a cross-sectional view of a conventional microwave integrated circuit. 11...l! Electric suspension body plate, 12...Metal thin film, 13.
... Insulating film, 21 ... Semi-insulating GaAs substrate, 22.
...Vapor deposited thin film, 23...S t Q2 film agent Yoshihiro MorimotoyJ-...Insulation order Fig. 3 Fig. 2 (A)

Claims (1)

[Claims] 1. A microwave integrated circuit in which a total of five or more layers of metal thin films and insulating films are alternately formed on a dielectric substrate. 2. The microwave integrated circuit according to claim 1, wherein each metal thin film constitutes an independent electrode. 3. The dielectric substrate is a semi-insulating GaAs substrate, with three layers of metal thin films and two layers of insulating films, the second metal thin film of the three layers is grounded, and two The microwave integrated circuit according to claim 1, which is configured to operate as a capacitor.