Patent application number | Description | Published |
20080203471 | NITRIDE SEMICONDUCTOR DEVICE AND METHOD FOR PRODUCING NITRIDE SEMICONDUCTOR DEVICE - The nitride semiconductor device includes: a nitride semiconductor structure comprising an n-type first layer, a p-type second layer, and an n-type third layer, the nitride semiconductor structure comprising a mesa structure having a lateral surface which forms a wall surface extending from the first, second, to third layers; a gate insulating film formed on the wall surface of the mesa structure; a gate electrode formed as facing the wall surface in the second layer; a drain electrode electrically connected to the first layer; and a source electrode electrically connected to the third layer, the nitride semiconductor structure having a high dislocation region and a low dislocation region arranged along a direction parallel to a principal surface of lamination of the nitride semiconductor structure, a dislocation density of the low dislocation region being lower than that of the high dislocation region, the mesa structure being formed in the low dislocation region. | 08-28-2008 |
20080308908 | Nitride semiconductor device and method for producing nitride semiconductor device - A nitride semiconductor device of the present invention includes: a nitride semiconductor laminated structure comprising an n type first layer, a second layer containing a p type dopant laminated on the first layer, and an n type third layer laminated on the second layer, each layer of the nitride semiconductor laminated structure made of a group III nitride semiconductor, and the nitride semiconductor laminated structure formed with a first trench and a second trench, the first trench penetrating the second layer from the third layer and reaching at least the first layer, and the second trench having a side wall extending from the first, second, to third layers and being different from the first trench; a surface insulating film containing at least silicon nitride formed such that the surface insulating film covers the surface of the first trench; a gate insulating film formed on the side wall of the second trench such that the gate insulating film extends over the first, second, and third layers; and a gate electrode formed such that the gate electrode is opposed to the side wall of the second trench with the gate insulating film sandwiched between the gate electrode and the side wall. | 12-18-2008 |
20080315210 | High electron mobility transistor - A GaN-based semiconductor layer is stacked on a GaN-based single-crystal substrate. The GaN-based single-crystal substrate forms an electron transit layer, and the GaN-based semiconductor layer forms an electron supply layer. A principal growth plane of the GaN-based single-crystal substrate is an m-plane, and a principal growth plane of the GaN-based semiconductor layer formed on the GaN-based single-crystal substrate is also an m-plane. With such a layer structure, no piezoelectric field is generated since the m-plane is a nonpolar plane. This suppresses generation of a two-dimensional electron gas layer at the time when no gate voltage is applied and consequently enables achievement of a normally-off configuration. | 12-25-2008 |
20080315256 | Nitride semiconductor device - A nitride semiconductor device according to the present invention includes: a nitride semiconductor laminated structure comprising a first layer made of a Group III nitride semiconductor, a second layer laminated on the first layer and made of an Al-containing Group III nitride semiconductor with a composition that differs from that of the first layer, the nitride semiconductor laminated structure comprising a stripe-like trench exposing a lamination boundary between the first layer and the second layer; a gate electrode formed to oppose the lamination boundary; and a source electrode and a drain electrode, having the gate electrode interposed therebetween, each connected electrically to the second layer. | 12-25-2008 |
20090026556 | Nitride semiconductor device and method for producing nitride semiconductor device - A method for producing a nitride semiconductor device according to the present invention includes the steps of: forming an insulating film containing oxygen on the surface of a group III nitride semiconductor; and placing the group III nitride semiconductor under a nitrogen atmosphere in advance of the step of forming the insulating film. A nitride semiconductor device according to the present invention includes a group III nitride semiconductor; and an insulating film containing oxygen formed on the surface of the group III nitride semiconductor, wherein the nitrogen concentration in a region provided with the insulating film is higher than the nitrogen concentration in a region not provided with the insulating film on the surface of the group III nitride semiconductor. | 01-29-2009 |
20090039421 | Nitride semiconductor device and method for producing nitride semiconductor device - A nitride semiconductor device of the present invention includes a nitride semiconductor laminated structure comprising an n type first layer, a second layer containing a p type dopant laminated on the first layer, and an n type third layer laminated on the second layer, each layer of the nitride semiconductor laminated structure made of a group III nitride semiconductor, and the nitride semiconductor laminated structure having a wall surface extending the first, through the second, to the third layers; a gate insulating film formed on the wall surface such that the gate insulating film extends for the first, second, and third layers; a gate electrode formed such that the gate electrode is opposed to the wall surface of the second layer with the gate insulating film sandwiched between the gate electrode and the wall surface; | 02-12-2009 |
20090057684 | Nitride semiconductor device and method for producing nitride semiconductor device - A nitride semiconductor device includes: a semiconductor base layer made of a conductive group III nitride semiconductor having a principal plane defined by a nonpolar plane or a semipolar plane; an insulating layer formed on the principal plane of the semiconductor base layer with an aperture partially exposing the principal plane; a nitride semiconductor multilayer structure portion, formed on a region extending onto the insulating layer from the aperture, having a parallel surface parallel to the principal plane of the semiconductor base layer as well as a +c-axis side first inclined surface and a −c-axis side second inclined surface inclined with respect to the principal plane of the semiconductor base layer and including two types of group III nitride semiconductor layers at least having different lattice constants; a gate electrode formed to be opposed to the second inclined surface; a source electrode arranged to be electrically connected with the group III nitride semiconductor layers; and a drain electrode formed on a back surface of the semiconductor base layer opposite to the principal plane. | 03-05-2009 |
20090179258 | NITRIDE SEMICONDUCTOR DEVICE AND METHOD FOR PRODUCING NITRIDE SEMICONDUCTOR DEVICE - A nitride semiconductor device includes: a nitride semiconductor structure portion including a first layer made of an n-type group III nitride semiconductor, a second layer made of a group III nitride semiconductor containing a p-type impurity provided on the first layer and an n-type region formed on a part of the second layer, and having a wall surface extending over the first layer, a body region of the second layer other than the n-type region and the n-type region; a gate insulating film formed such that the gate insulating film is opposed to the body region on the wall surface; a gate electrode formed such that the gate electrode is opposed to the body region through the gate insulating film; a source electrode formed such that the source electrode is electrically connected to the n-type region; a drain electrode formed such that the drain electrode is electrically connected to the first layer; and a body electrode formed such that the body electrode is electrically connected to the body region. | 07-16-2009 |
20090321854 | MIS FIELD EFFECT TRANSISTOR AND METHOD FOR MANUFACTURING THE SAME - An MIS field effect transistor includes a nitride semiconductor multilayer structure including a first group III-V nitride semiconductor layer of a first conductivity type, a second group III-V nitride semiconductor layer of a second conductivity type which is arranged on the first group III-V nitride semiconductor layer, and a third group III-V nitride semiconductor layer of the first conductivity type which is arranged on the second group III-V nitride semiconductor layer. A gate insulating film is formed on a wall surface ranging over the first, second and third group III-V nitride semiconductor layers so that the film stretches over the first, second and third group III-V nitride semiconductor layer. A gate electrode made of a conductive material is formed so that it faces the second group III-V nitride semiconductor layer via the gate insulating film. A drain electrode is provided to be electrically connected to the first group III-V nitride semiconductor layer, and a source electrode is provided to be electrically connected to the third group III-V nitride semiconductor layer. | 12-31-2009 |
20100047976 | METHOD FOR FORMING NITRIDE SEMICONDUCTOR LAMINATED STRUCTURE AND METHOD FOR MANUFACTURING NITRIDE SEMICONDUCTOR ELEMENT - The method for forming a nitride semiconductor laminated structure according to the present invention includes: a first layer forming step of forming an n-type or i-type first layer composed of a group III nitride semiconductor; a second layer forming step of laminating a p-type second layer composed of a group III nitride semiconductor and containing Mg on the first layer; and a third layer forming step of forming an n-type or i-type third layer composed of a group III nitride semiconductor on the second layer after the second layer forming step. | 02-25-2010 |
20100078688 | NITRIDE SEMICONDUCTOR DEVICE, NITRIDE SEMICONDUCTOR PACKAGE, AND METHOD FOR MANUFACTURING NITRIDE SEMICONDUCTOR DEVICE - A nitride semiconductor device of the present invention includes: a nitride semiconductor laminated structure including an n-type first layer, a second layer that is laminated on the first layer and contains a p-type impurity, and an n-type third layer laminated on the second layer, each layer of the nitride semiconductor laminated structure being made of a Group III nitride semiconductor, and having a wall surface extending from the first, second, to third layers; a fourth layer that is formed on the wall surface in the second layer and that has a different conductive characteristic from that of the second layer; a gate insulating film formed to contact the fourth layer; and a gate electrode formed as facing the fourth layer with the gate insulating film being sandwiched between the gate electrode and the fourth layer. | 04-01-2010 |