Abstract: A semiconductor device includes: a nitride group semiconductor functional layer including a second nitride group semiconductor region on a first nitride group semiconductor region where a two-dimensional carrier gas layer is made, the second nitride group semiconductor region functioning as a barrier layer; a first main electrode electrically connected to one end of the two-dimensional carrier gas layer; a second main electrode electrically connected to the other end of the two-dimensional carrier gas layer; and a metal oxide film placed between the first and second main electrodes, electrically connected to the first main electrode, the first main electrode extends over an upper surface of the metal oxide film.

Abstract: A compound semiconductor device includes a compound semiconductor layer in which a two-dimensional carrier gas layer is formed, the compound semiconductor layer including a carrier travel layer and a carrier supply layer; first and second main electrodes, which are arranged apart from each other on the compound semiconductor layer, and are ohmically connected to the two-dimensional carrier gas layer; a metal oxide semiconductor film arranged on the compound semiconductor layer between the first main electrode and the second main electrode; and a control electrode arranged on the metal oxide semiconductor film, the control electrode including a titanium film that contacts the metal oxide semiconductor film or a titanium-containing compound film that contacts the metal oxide semiconductor film.

Abstract: A nitride compound semiconductor device includes a semiconductor layer including a group III nitride compound semiconductor, source and drain electrodes provided on the semiconductor layer, an insulating film provided on the semiconductor layer between the source electrode and the drain electrode, an organic semiconductor layer in contact with the semiconductor layer at an opening provided for the insulating film, and a gate electrode provided on the organic conductive layer at the opening.

Abstract: A semiconductor device having a GaN-based main semiconductor region formed on a silicon substrate via a buffer region. Source, drain and gate electrodes are formed on the main semiconductor region, and a back electrode on the back of the substrate. The substrate is constituted of two semiconductor regions of opposite conductivity types, with a pn junction therebetween which is conducive to a higher voltage-withstanding capability between the drain and back electrodes.

Abstract: A two-dimensional carrier is generated in the vicinity of an interface that is a hetero interface between a semiconductor layer and a semiconductor layer. Two concave portions are formed so as to extend from a primary surface as far as the interface. An electrode that is made of metal and provides a Schottky junction with the semiconductor layers is formed on a bottom surface and a side surface of the concave portion. An electrode that is made from metal and provides a low resistance contact with the semiconductor layers and is also in low resistance contact therewith is formed on the bottom surface and side surface of the concave portion. As a result, a semiconductor device is provided in which contact resistance between the electrodes and the semiconductor layers is reduced and high frequency characteristics are improved.

Abstract: A semiconductor device include: a nitride group semiconductor functional layer including a second nitride group semiconductor region on a first nitride group semiconductor region where a two-dimensional carrier gas layer is made, the second nitride group semiconductor region functioning as a barrier layer; a first main electrode electrically connected to one end of the two-dimensional carrier gas layer; a second main electrode electrically connected to the other end of the two-dimensional carrier gas layer; and metal oxide films placed between the first and second main electrodes, electrically connected to the first main electrode, and reducing a carrier density of the two-dimensional carrier gas layer.

Abstract: A compound semiconductor element is provided which electrically connects an electrode 3 formed on one main surface 2a of a compound semiconductor region 2 with a substrate 5 to fix an electric potential of substrate 5 at an electric potential of electrode 3, thereby preventing fluctuation in electric potential of substrate 5 under the changing operating condition of the device for stabilization in electric property of the device. Also, formed between compound semiconductor region 2 and substrate 5 is an insulating layer 6 for blocking a leakage current which may flow longitudinally between one main surface 2a of compound semiconductor region 2 and substrate 5 so that sufficiently high withstand voltage property can be given between compound semiconductor region 2 and substrate 5.

Abstract: A compound semiconductor element is provided which electrically connects an electrode 3 formed on one main surface 2a of a compound semiconductor region 2 with a substrate 5 to fix an electric potential of substrate 5 at an electric potential of electrode 3, thereby preventing fluctuation in electric potential of substrate 5 under the changing operating condition of the device for stabilization in electric property of the device. Also, formed between compound semiconductor region 2 and substrate 5 is an insulating layer 6 for blocking a leakage current which may flow longitudinally between one main surface 2a of compound semiconductor region 2 and substrate 5 so that sufficiently high withstand voltage property can be given between compound semiconductor region 2 and substrate 5.

Abstract: A nitride compound semiconductor device includes a semiconductor layer including a group III nitride compound semiconductor, source and drain electrodes provided on the semiconductor layer, an insulating film provided on the semiconductor layer between the source electrode and the drain electrode, an organic semiconductor layer in contact with the semiconductor layer at an opening provided for the insulating film, and a gate electrode provided on the organic conductive layer at the opening.

Abstract: A compound semiconductor element is provided which electrically connects an electrode 3 formed on one main surface 2a of a compound semiconductor region 2 with a substrate 5 to fix an electric potential of substrate 5 at an electric potential of electrode 3, thereby preventing fluctuation in electric potential of substrate 5 under the changing operating condition of the device for stabilization in electric property of the device. Also, formed between compound semiconductor region 2 and substrate 5 is an insulating layer 6 for blocking a leakage current which may flow longitudinally between one main surface 2a of compound semiconductor region 2 and substrate 5 so that sufficiently high withstand voltage property can be given between compound semiconductor region 2 and substrate 5.

Abstract: A semiconductor device having: a substrate; nitride-based compound semiconductor layers formed on one main surface of the substrate and made of a nitride-based compound semiconductor; a first electrode formed on the nitride-based compound semiconductor layers and having a Schottky junction with the nitride-based compound semiconductor layers; and a second electrode formed on the nitride-based compound semiconductor layers and subjected to low resistance contact with the nitride-based compound semiconductor layers, wherein the first electrode and substrate are electrically connected through a connection conductor.

Abstract: A Schottky diode includes a substrate, a channel layer formed on the substrate and made of nitride-based compound semiconductor, an anode electrode and a cathode electrode which constitute an end portion of the current path of the semiconductor element, and a dummy electrode electrically connected to the substrate. The anode electrode is formed to have a Schottky barrier junction with the channel layer. The cathode layer is formed to have a low-resistance contact with the channel layer.

Abstract: A two-dimensional carrier is generated in the vicinity of an interface that is a hetero interface between a semiconductor layer and a semiconductor layer. Two concave portions are formed so as to extend from a primary surface as far as the interface. An electrode that is made of metal and provides a Schottky junction with the semiconductor layers is formed on a bottom surface and a side surface of the concave portion. An electrode that is made from metal and provides a low resistance contact with the semiconductor layers and is also in low resistance contact therewith is formed on the bottom surface and side surface of the concave portion. As a result, a semiconductor device is provided in which contact resistance between the electrodes and the semiconductor layers is reduced and high frequency characteristics are improved.

Abstract: A semiconductor device having a GaN-based main semiconductor region formed on a silicon substrate via a buffer region. Source, drain and gate electrodes are formed on the main semiconductor region, and a back electrode on the back of the substrate. The substrate is constituted of two semiconductor regions of opposite conductivity types, with a pn junction therebetween which is conducive to a higher voltage-withstanding capability between the drain and back electrodes.