| 摘要 |
PURPOSE:To realize a line with a low characteristic impedance on a dielectric substrate with a small conductor loss by overlapping mutually a conductor constituting a transmission line via an insulation film. CONSTITUTION:The insulation film 15 is formed on a conductor film 14 formed on the dielectric substrate (semi-insulating semiconductor substrate) 6 and a conductor film 16 is overlapped so as to clip it. Since the two conductor films are overlapped over a wide area, the current is distributed widely around the part as a center. Thus, the conductor loss is decreased. Since the capacitance between the conductors is increased depending on the width of the part where the conductor films 14 and 16 are overlapped and the thickness of the insulation film, the characteristic impedance is decreased. Moreover, the conductor films 17, 18 are arranged with a gap on the substrate 1 as shown in Fig. B and the center conductor 19 is overlapped on the upper part via the insulation film 15. Such structure is attained also. |
