JPH01204477A - Field-effect ultrahigh-frequency semiconductor device - Google Patents

Abstract

PURPOSE:To reduce a pellet in size by independently insetting input/output impedance matching circuits to N (N>=2) pieces of basic cells connected in parallel with each other. CONSTITUTION:Basic cells in which series circuits of N-square spiral inductance elements 4 (N>=2) made of pectinated electrode field-effect transistors and capacity elements 5 of thin film multilayer structure are inserted as matching circuits, are connected in parallel, and independently inserted to all the inputs and outputs of the cells 10. Thus, since each cell 10 can be impedance-matched, the input/output impedance matchings can be conducted in more accurate state. Accordingly, originally preferably characteristics of the FET can be employed in an external circuit at the points of gain, band, etc., as compared with the simultaneous matching of a conventional multi-cell field-effect transistor(FET). In this manner, the area of the pellet of the FET can be reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a field effect type ultra-high frequency semiconductor device, and in particular, to a field effect type ultrahigh frequency semiconductor device.
The present invention relates to a high-output microwave field effect transistor device in which several cells (N>2) are connected in parallel.

[Conventional technology]

Today, microwave field effect transistor devices (hereinafter simply referred to as FETs) are made of gallium arsenide (GaAs).
) is mainly used. This GaAsFET is usually used as a high-output microwave amplifier, and is a multi-cell device that obtains high output by arranging a plurality of basic cells in parallel, each having one gate and drain bonding electrode. configuration is common.

[Problem to be solved by the invention]

As described above, since the conventional high-output FET has a multi-cell configuration, the input/output impedance is extremely low, and the FET alone cannot fully bring out its characteristics. Therefore, an impedance matching circuit consisting of a microstrip line formed on an alumina substrate or a chip capacitor formed on a high dielectric substrate is usually inserted all at once on the input and output sides of the FET pellet.
Formed to be incorporated into one package. However, a high output FE with a built-in matching circuit like this
Even with T, if you try to increase the output by further increasing the number of cells, the input/output impedance of the FET pellet will become even lower, making it difficult to configure a matching circuit, making it impossible to secure sufficient gain and gain band. It disappears. For example, 1
In the 0GHz band, problems occur when the number of basic cells exceeds 8,
In the 30 GHz band, the standing wave ratio (VSWR) will exceed 2 even if two devices are connected in parallel.

In view of the above circumstances, an object of the present invention is to provide a field-effect ultra-high frequency semiconductor device that exhibits sufficient gain and gain band characteristics in an ultra-high frequency band exceeding 10 GHz.

[Means to solve the problem]

According to the present invention, a field effect ultra-high frequency semiconductor device includes N (N>
2) The basic cells are connected in parallel, and input/output impedance matching circuits are independently inserted into all the input and output sides of the basic cells.

That is, according to the present invention, N (N>2
) basic cells, input and output impedance matching circuits are inserted independently. In the case of a device configuration in which multiple basic cells are connected in parallel, it is obvious that the input/output impedance of each basic cell that makes up the device is higher than that of the entire device, so the configuration of the matching circuit becomes easier. , and it becomes possible to fully bring out the characteristics of each field effect transistor constituting the basic cell to an external circuit. That is, since the matching circuit can be configured with a simple circuit in which an inductance element and a capacitance element are connected in series, it is also possible to reduce the size of the pellet.

〔Example〕

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a plan view of a field effect type super high frequency semiconductor device showing an embodiment of the present invention. According to this embodiment, the field-effect ultra-high frequency semiconductor device of the present invention includes a rectangular spiral inductance element 4 and a thin film multilayer structure between a source electrode 1 and a gate electrode 3 and between a source electrode 1 and a drain electrode 2. It includes a parallel connection circuit consisting of a plurality of basic cells 10 each having a series circuit of capacitive elements 5 inserted therein as a matching circuit. Here, the capacitive element 5 having a thin film multilayer structure is formed in a sandwich structure with a dielectric interposed between it and the source electrode 1, and the rectangular spiral inductance element 4 is formed on a substrate. At this time, the series circuit of these two circuit elements functions as an input/output impedance matching circuit for each of the basic cells L, and if the basic cell 10 is composed of commonly used gallium arsenide FETs, eight Even if the above parallel connection configuration is used, the inductance and capacitance will each be 1 pico Farad (PF).
and 0. By selecting O1 to 0.1 nano-Henry (n H'), it is possible to set the impedance matching of the semiconductor device to a standing wave ratio of 1.2 or less in an operating band of 10 GHz. In other words, the characteristics of each basic cell 10 can be sufficiently extracted to the outside using an extremely simple matching circuit, and an extremely large multi-cell configuration can be easily obtained. We can definitely make this happen.

FIG. 2 is a plan view of a field effect type super high frequency semiconductor device showing another embodiment of the present invention. According to this embodiment, an impedance matching circuit consisting of a series circuit of a zigzag-shaped inductor element 6 and a comb-shaped capacitive element 7 is provided between the source electrode [1 and the gate electrode 3 and between the source electrode 1 and the drain electrode 2, respectively]. A pair is inserted every time cell L is updated. According to this embodiment, since the capacitive element can be formed into a distributed constant type, there is an advantage that matching can be achieved more easily.

〔Effect of the invention〕

As described above in detail, according to the present invention, the following effects can be obtained by providing a matching circuit consisting of an inductance element and a capacitance element for each cell in a multi-cell FET.

(1) Since impedance matching is performed for each cell, impedance matching can be achieved in a higher state. Therefore, rather than matching all at once as in conventional multi-cell FETs, it is possible to extract more of the FET's inherently good characteristics in terms of gain and band to an external circuit.

(2) Instead of using a conventional low-pass filter type matching circuit consisting of an inductance element and a capacitance element as a matching circuit, a series circuit of an inductance element and a capacitance element is inserted in the gate electrode and the drain electrode in parallel with the FET section, respectively. Since it can have a simple circuit configuration, FET
The pellet area can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a field effect type ultra-high frequency semiconductor device showing one embodiment of the invention, and FIG. 2 is a plan view of an ultra high frequency semiconductor device showing another embodiment of the invention. 1... Source electrode, 2... Drain electrode, 3...
Gate electrode, 4... Rectangular spiral inductance element, 5... Capacitive element with thin film multi-M structure, 6... Zigzag-shaped inductance element, 7... Comb-shaped capacitive element,
L change...Basic cell. Agent Patent Attorney Uchihara Otokabu 1 Tuho 2 Illustration

Claims (2)

[Claims] (1) N(
A field-effect ultra-high frequency semiconductor device comprising N≧2) basic cells connected in parallel, and characterized in that input/output impedance matching circuits are independently inserted on all input sides and output sides of the basic cells. . (2) The input/output impedance matching circuit is characterized by comprising a series circuit of an inductance circuit element and a capacitance circuit element each independently connected between the gate electrode and the source electrode and between the source electrode and the drain electrode of the basic cell. A field effect type super high frequency semiconductor device according to claim (1).