JPS62291071A - Field-effect transistor - Google Patents

Abstract

PURPOSE:To permit each FET unit to be operated under the same phase and improve RF characteristics in a case of FET in one chip that is an aggregate of FET unit by making a signal transmission distance from an input feed end to each gate electrode equal in the case of FET where the gate electrodes are arranged in a form of comb. CONSTITUTION:In an FET type transistor, in which gate electrodes 1 are arranged in a form of comb, the closer each gate electrode 2 gets to an input feed end 4, the longer it requires a distance between a gate electrode 1 and bus bar electrodes 3 and as a result, the above arrangement makes a signal transmission distance from the input feed end 4 to each gate electrode 1 equal and allows each FET unit consisting of each gate electrode 1 to be operated under the same phase. For instance, when the distance from the input feed end 4 to the bus bar electrode 1 is represented by a and each pitch between the gate electrodes is represented by b and the distances between the gate electrode 1 corresponding to each gate electrode and the bus bar electrodes 3 are represented by C1-C4 as well as the distances from the input feed ends to each gate electrode are represented by L1-L4, C1-C4 are set so that the following equations: L1=L2=L3=L4 are valid, provided that L1=a+4b+C1, L2=a+3b+C2, L3=a+2b+C3, and L4=a+b+C4.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a GaAs ME8FET, and the present invention relates to a GaAs ME8FET. This invention relates to improving the RE' characteristic by operating the unit FETs in the same phase instead of operating in the same phase.

[Conventional technology]

Conventionally, this type of electrode shape has been as shown in Figure 2, in which the connection area between the gate electrode and the busbar electrode is formed in the same shape, and as a result, the signal propagation distance from the input feed end to each gate electrode is different. It was.

[Problem that the invention seeks to solve]

In the conventional electrode shape described above, the input signal reaches the gate electrode closest to the input power supply end the earliest, and the input signal arrives at the other gate 1d poles that gradually move away from the input power supply end with a time delay. Daughters are generated, and each unit, T''ET, made up of each gate electrode no longer operates in the same phase.As a result, one chip of GaAs, which is a collection of units FE'I'', F”ET fLF
The disadvantage is that the characteristics deteriorate.

[Means for solving problems]

The feature of the present invention is that, as shown in Figure 1-1, the electrode shape (signal propagation distance l!#) between the gate electrode and the busbar electrode is made different for each valley gate electrode. 11f and other shapes in which the signal propagation distances to the electrodes are equal are used.

〔Example〕

The present invention will be explained with reference to FIG. For example, the shape between the gate electrode and the bus bar electrode is made spiral. The distance from the input power supply end to the busbar electrode is a, the pitch between the valley gate electrodes is b, and the gate 1J1 pole is 1°2, 3, l?
- Inquiry about the gate electrode and the passbar electrode! llt
Let them be c, , I CZ ICM + C4, respectively.

The distance from the input supply '111 to the valley gate electrode is L, 2
, 3.4, then LH-2+ 4 b + CI L2 "" a + 3 b 10C! L3 := a + 2 b + c 3L, 2 a+
b+c4 C3:21)+Cric4-=3b+C.

If it is set so that ==L, =L3=1, 4, the signal propagation distance in all gate electrode trenches becomes equal.

〔Effect of the invention〕

As explained below, in the present invention, each unit F E 'I' is made equal by equalizing the signal propagation distance from the input feed end to each gate electrode in ()aAsMEsIi'ET in which gate electrodes are arranged in a comb shape. Operates in the same phase, resulting in a unit)”ETIP JI which is a collection of
' It is effective in improving the RF characteristics of ET.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the present invention, and FIG. 2 is a plan view of a conventional structure. ■...Gate electrode, 2-...Connection area between gate electrode and busbar electrode, 3...Busbar electrode, 4
...Input power supply end.

Claims (1)

[Claims] In a field effect transistor in which gate electrodes are arranged in a comb shape, the distance between the gate electrode and the busbar electrode is made longer as it approaches the input power supply end, and as a result, the signal propagation distance from the input power supply end to each gate electrode is increased. A field effect transistor characterized in that each unit FET constituted by each gate electrode operates in the same phase by being made equal.