Patent application number | Description | Published |
20090140295 | GaN-based semiconductor device and method of manufacturing the same - A GaN-based semiconductor device includes a silicon substrate; an active layer of a GaN-based semiconductor formed on the silicon substrate; a trench formed in the active layer and extending from a top surface of the active layer to the silicon substrate; a first electrode formed on an internal wall surface of the trench so that the first electrode extends from the top surface of the active layer to the silicon substrate; a second electrode formed on the active layer so that a current flows between the first electrode and the second electrode via the active layer; and a bottom electrode formed on a bottom surface of the silicon substrate. The first electrode is formed of a metal capable of being in ohmic contact with the silicon substrate and the active layer. | 06-04-2009 |
20090278172 | GaN based semiconductor element - The field effect transistor includes a laminated structure in which a buffer layer, and an electron transporting layer (undoped GaN layer), and an electron supplying layer (undoped AlGaN layer) are laminated in sequence on a sapphire substrate. An npn laminated structure is formed on a source region of the electron supplying layer, and a source electrode is formed on the npn laminated structure. A drain electrode is formed in a drain region of the electron supplying layer, and an insulating film is formed in an opening region formed in the gate region. When a forward voltage greater than a threshold is applied to the gate electrode, an inversion layer is formed and the drain current flows. By changing a thickness and an impurity concentration of the p-type GaN layer, the threshold voltage can be controlled. The electrical field concentration between the gate electrode and the drain electrode is relaxed due to the drift layer, and voltage resistance improves. | 11-12-2009 |
20100032683 | GaN-BASED SEMICONDUCTOR ELEMENT - The GaN-based semiconductor element | 02-11-2010 |
20100117146 | SEMICONDUCTOR DEVICE AND METHOD FOR FABRICATING THE SAME - There is provided a semiconductor device and a method for fabricating the same whose withstanding characteristic may be enhanced and whose ON resistance may be reduced. A MIS-type HEMT includes a carrier traveling layer made of a group-III nitride semiconductor and formed on a supporting substrate, a carrier supplying layer made of a group-III nitride semiconductor and formed on the carrier traveling layer, source and drain electrodes formed on the carrier supplying layer, insulating films formed on the carrier supplying layer and a gate electrode formed on the insulating films. The insulating film is formed in a region interposed between the source and drain electrodes and has a trench whose cross-section is inverted trapezoidal and whose upper opening is wider than a bottom thereof. The gate electrode is formed at least from the bottom of the trench onto the insulating films on the side of the drain electrode. | 05-13-2010 |
20100117186 | Semiconductor device and method of producing the same - The invention provides a semiconductor device and a method for fabricating the same capable of preventing a field plate portion from being delaminated from an insulating film by stress inherent in a semiconductor layer even if the stress is released in forming a trench in part of the semiconductor layer where the semiconductor device is to be separated and capable of having a higher breakdown property of the semiconductor device. The semiconductor device has source, drain and gate electrodes, insulating films that insulate the electrodes on an electron supplying layer and a mesa-structure formed at part where the semiconductor device is to be separated. The gate electrode has a first electrode layer having a function of the electrode and a second electrode layer having a field plate portion whose part that contacts with the insulating film is made of a metallic material that adheres well to the insulating film. | 05-13-2010 |
20100210080 | METHOD OF MANUFACTURING GAN-BASED TRANSISTORS - A method of manufacturing a GaN-based field effect transistor is provided by which a lower resistance and a higher breakdown voltage are obtained and which is less affected by a current collapse. A method of manufacturing the GaN-based field effect transistor(s) can comprise performing an epitaxial growth of an AlN layer ( | 08-19-2010 |
20110198669 | TRANSISTOR AND METHOD FOR FABRICATING THE SAME - The invention provides a transistor having a leak current between a source and drain in a nitride compound semiconductor formed on a substrate that is reduced. A gate electrode, a source electrode and a drain electrode are formed respectively on the surface of the nitride compound semiconductor formed on the silicon substrate in the transistor. At least one of the source electrode and the drain electrode is surrounded by an auxiliary electrode connected with the gate electrode. Because a depletion layer is formed in the nitride compound semiconductor under the auxiliary electrode, a route of the leak current is shut off and the leak current between the source and drain may be effectively reduced. | 08-18-2011 |
20110241017 | FIELD EFFECT TRANSISTOR - A field effect transistor includes: a buffer layer that is formed on a substrate; a high resistance layer or a foundation layer that is formed on the buffer layer; a carbon-containing carrier concentration controlling layer that is formed on the high resistance layer or the foundation layer; a carrier traveling layer that is formed on the carrier concentration controlling layer; a carrier supplying layer that is formed on the carrier traveling layer; a recess that is formed from the carrier supplying layer up to a predetermined depth; source/drain electrodes that are formed on the carrier supplying layer with the recess intervening therebetween; a gate insulating film that is formed on the carrier supplying layer so as to cover the recess; and a gate electrode that is formed on the gate insulating film in the recess | 10-06-2011 |
20110241088 | FIELD EFFECT TRANSISTOR, METHOD OF MANUFACTURING FIELD EFFECT TRANSISTOR, AND METHOD OF FORMING GROOVE - A field effect transistor includes a high resistance layer on a substrate, a semiconductor operation layer that is formed on the high resistance layer and includes a channel layer that has the carbon concentration of not more than 1×10 | 10-06-2011 |
20110316048 | SEMICONDUCTOR DEVICE AND METHOD FOR FABRICATING THE SAME - There is provided a semiconductor device and a method for fabricating the same whose withstanding characteristic may be enhanced and whose ON resistance may be reduced. A MIS-type HEMT includes a carrier traveling layer made of a group-III nitride semiconductor and formed on a supporting substrate, a carrier supplying layer made of a group-III nitride semiconductor and formed on the carrier traveling layer, source and drain electrodes formed on the carrier supplying layer, insulating films formed on the carrier supplying layer and a gate electrode formed on the insulating films. The insulating film is formed in a region interposed between the source and drain electrodes and has a trench whose cross-section is inverted trapezoidal and whose upper opening is wider than a bottom thereof. The gate electrode is formed at least from the bottom of the trench onto the insulating films on the side of the drain electrode. | 12-29-2011 |
20110318913 | SEMICONDUCTOR DEVICE AND METHOD FOR FABRICATING THE SAME - There is provided a semiconductor device and a method for fabricating the same whose withstanding characteristic may be enhanced and whose ON resistance may be reduced. A MIS-type HEMT includes a carrier traveling layer made of a group-III nitride semiconductor and formed on a supporting substrate, a carrier supplying layer made of a group-III nitride semiconductor and formed on the carrier traveling layer, source and drain electrodes formed on the carrier supplying layer, insulating films formed on the carrier supplying layer and a gate electrode formed on the insulating films. The insulating film is formed in a region interposed between the source and drain electrodes and has a trench whose cross-section is inverted trapezoidal and whose upper opening is wider than a bottom thereof. The gate electrode is formed at least from the bottom of the trench onto the insulating films on the side of the drain electrode. | 12-29-2011 |
20120193639 | GaN-BASED SEMICONDUCTOR ELEMENT - A GaN-based semiconductor element includes a substrate, a buffer layer formed on the substrate, including an electrically conductive portion, an epitaxial layer formed on the buffer layer, and a metal structure in ohmic contact with the electrically conductive portion of the buffer layer for controlling an electric potential of the buffer layer. | 08-02-2012 |