JPS604207A - Inter-digital capacitor - 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 The present invention relates to improvements in interdigital capacitors made of microwave integrated circuits.

The structure of a conventional interdigital capacitor is shown in FIGS. 1 and 2. FIG. 1 is a perspective view.

FIG. 2 is a side view of FIG. 1 taken along the plane A-A'. In Figure 1, (l) is a dielectric substrate, (2) is a ground conductor, (3) is a first terminal, (4) is a second terminal, (5) is a
) is the first finger, (6) is the second finger, (
7) is the terminal line.

Ground conductor (2), first terminal (3), second terminal (4)
, first finger (5), second finger f6),
The terminal line (7) is constructed by providing a metal film on the dielectric substrate (1) by vapor deposition or the like.

Incidentally, there are cases where it is necessary to increase the capacitance between adjacent fingers in one or more configurations of interdigital capacitors.

However, in the conventional interdigital capacitor, the opposing first finger (5) and second finger (6)
The disadvantage was that it was difficult to increase the capacity between the fingers because the two sides of the gap were filled with air.

Furthermore, since the metal film constituting the finger is in direct contact with the outside world, it has the disadvantage of being easily damaged.

This invention aims to eliminate these drawbacks.

A recess is provided in the dielectric substrate (1) to realize a cold state in which the dielectric exists in the gap between the opposing first finger (5) and second finger (6).5. It is possible to increase the volume between the five adjacent fingers, and the metal handle is made of oak that is less likely to be damaged. The drawings will be explained below.

FIG. 3 is a perspective view of an interdigital capacitor according to the present invention, and FIG. 4 is a sectional view taken along line A--A in FIG. 3.

In Figure 4: I? (8) is the first finger (5)
and a recess provided to embed the second finger (6) in the dielectric substrate (1).

Possible methods for providing the digging (8) include etching, rock-cutting, etc. In the interdigital capacitor according to the present invention, the opposing first fingers (
5) and the second finger (6), there is an advantage that each floor between the fingers can be large compared to a conventional interdigital capacitor. Further, the problem of damaging a portion of the dowel finger due to the metal film existing inside the recess is eliminated.

Note that although the coupling of interdigital capacitors has been described above, the present invention is not limited thereto, and may be used for circuit elements such as coupling lines.

Further, the present invention may be used in a monolithic microwave integrated circuit.As described above, in the interdigital capacitor according to the present invention, by providing the recesses (8), the opposing first fingers (5) Second finger (6)
By realizing a state in which a dielectric material exists in the gap portion, it is possible to increase the capacitance between the fingers, and there is an advantage that there is no problem of damaging a portion of the fingers.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional interdigital capacitor.
2 is a cross-sectional view of FIG. 1 taken along the A-A plane, FIG. 3 is a perspective view of the interdigital capacitor according to the present invention, and FIG. 4 is a cross-sectional view of FIG. 3 taken along the A-A/plane. (1) is a dielectric substrate. (2) is the ground conductor, (3) is the first terminal, and (4) is the second terminal.
terminal. (5) is the first finger, and (6) is the second finger. (7) is the terminal track, and (8) is the digging. Note that the same or corresponding parts in FIG. 9 are designated by the same reference numerals. Agent Masuo Oiwa @ 1. Domestic demand 2. Commercial market 3. 4.

Claims (1)

[Claims] In an interdigital capacitor made of a microwave integrated circuit configured by arranging two strip conductors having a plurality of fingers facing each other on a dielectric substrate, a plurality of recesses are provided on the dielectric substrate. , an interdigital capacitor in which each finger is arranged within each of the above-mentioned grooves.