Abstract: There is provided a compound semiconductor device having a capacitor, to prevent a leakage current flowing between an upper electrode and a lower electrode of the capacitor via an insulating protective film. The compound semiconductor device comprises a first electrode of a capacitor formed on a compound semiconductor substrate via a first insulating film, a dielectric film of the capacitor formed on the first electrode, a second electrode of a capacitor formed on the dielectric film, a second insulating film for covering an upper surface and side surfaces of the second electrode, and an insulating protective film for covering the second insulating film, the dielectric film, the first electrode and the first insulating film, and having a hydrogen containing rate which is larger than the second insulating film.

Abstract: There is provided a compound semiconductor device having a capacitor, to prevent a leakage current flowing between an upper electrode and a lower electrode of the capacitor via an insulating protective film. The compound semiconductor device comprises a first electrode of a capacitor formed on a compound semiconductor substrate via a first insulating film, a dielectric film of the capacitor formed on the first electrode, a second electrode of a capacitor formed on the dielectric film, a second insulating film for covering an upper surface and side surfaces of the second electrode, and an insulating protective film for covering the second insulating film, the dielectric film, the first electrode and the first insulating film, and having a hydrogen containing rate which is larger than the second insulating film.

Abstract: There is provided a compound semiconductor device having a capacitor, to prevent a leakage current flowing between an upper electrode and a lower electrode of the capacitor via an insulating protective film. The compound semiconductor device comprises a first electrode of a capacitor formed on a compound semiconductor substrate via a first insulating film, a dielectric film of the capacitor formed on the first electrode, a second electrode of a capacitor formed on the dielectric film, a second insulating film for covering an upper surface and side surfaces of the second electrode, and an insulating protective film for covering the second insulating film, the dielectric film, the first electrode and the first insulating film, and having a hydrogen containing rate which is larger than the second insulating film.

Abstract: The impurity concentration contained in a layer on an electron supply layer of a high electron mobility field effect transistor is set in the range of 1˜1016 to 1˜1017 atoms/cm3, or the bandgap of a Schottky layer is set wider than that of the electron supply layer. Otherwise, in the steps of manufacturing the high electron mobility field effect transistor, after a silicon nitride film has been formed on a GaAs buried layer in which a second recess is formed and in a region on the inside of a first recess formed in a GaAs contact layer, the GaAs buried layer is still heated.

Abstract: The impurity concentration contained in a layer on an electron supply layer of a high electron mobility field effect transistor is set in the range of 1×1016 to 1×1017 atoms/cm3, or the bandgap of a Schottky layer is set wider than that of the electron supply layer. Otherwise, in the steps of manufacturing the high electron mobility field effect transistor, after a silicon nitride film has been formed on a GaAs buried layer in which a second recess is formed and in a region on the inside of a first recess formed in a GaAs contact layer, the GaAs buried layer is still heated.

Abstract: The impurity concentration contained in a layer on an electron supply layer of a high electron mobility field effect transistor is set in the range of 1×1016 to 1×1017 atoms/cm3, or the bandgap of a Schottky layer is set wider than that of the electron supply layer.