| 摘要 |
PURPOSE:To reduce characteristic impedance of a line, to suppress an increase in an area occupying wiring metal on a semiconductor substrate and to eliminate an increase in size of a device by forming wiring metal on the substrate through a dielectric film having higher permittivity than that of the substrate. CONSTITUTION:In a microwave semiconductor device having a semiconductor substrate 21 and wiring metal 24, the metal 24 is formed on the substrate 21 through a dielectric film 23 having higher permittivity than that of the substrate 21. For example, a nitride film (SiN) 22 having 7 of specific permittivity epsilonr is formed 1mum thick on a GaAs semiconductor substrate 21 having 100mum of thickness and 12.9 of the permittivity epsilonr, a high dielectric film 23 having 100 of specific permittivity epsilonr is formed 1mum thick on the film 22, and a microstrip line 24 is formed thereon. The materials of the film 23 includes, for example, TaOx having about 100 of the permittivity epsilonr, TiO2 having about 100-200 of the permittivity epsilonr, BaTiO3 having about 200-300 of the permittivity epsilonr, etc. |
