摘要:
A semiconductor device has a semiconductor substrate having a surface layer and a p-type semiconductor region, wherein the surface layer includes a contact region, a channel region and a drift region, the channel region is adjacent to and in contact with the contact region, the drift region is adjacent to and in contact with the channel region and includes n-type impurities at least in part, and the p-type semiconductor region is in contact with the drift region and at least a portion of a rear surface of the channel region, a main electrode disposed on the surface layer and electrically connected to the contact region, a gate electrode disposed on the surface layer and extending from above a portion of the contact region to above at least a portion of the drift region via above the channel region, and an insulating layer covering at least the portion of the contact region and not covering at least the portion of the drift region. The gate electrode and the contact region are insulated by the insulating layer, and the gate electrode and the drift region are in direct contact to form a Schottky junction.
摘要:
A nitride semiconductor device 2 comprises a nitride semiconductor layer 10. A gate insulating film 16 is formed on the surface of the nitride semiconductor layer 10. The gate insulating film 16 includes a portion composed of an aluminum nitride film 15 and a portion composed of an insulating material 14 that contains at least one of oxygen or silicon. A region W2 of the nitride semiconductor layer 10 facing the aluminum nitride film 15 is included in a region W1 of the nitride semiconductor layer 10 facing a gate electrode 18. The nitride semiconductor device 2 may further comprise a nitride semiconductor lower layer 8. The nitride semiconductor layer 10 may be stacked on the surface of the nitride semiconductor lower layer 8. The nitride semiconductor layer 10 may have a larger band gap than that of the nitride semiconductor lower layer 8 and have a heterojunction formed there between.
摘要:
A semiconductor device has a stacked structure in which a p-GaN layer, an SI-GaN layer, and an AlGaN layer are stacked, and has a gate electrode that is formed at a top surface side of the AlGaN layer. A band gap of the AlGaN layer is wider than a band gap of the p-GaN layer and the SI-GaN layer. Moreover, impurity concentration of the SI-GaN layer is less than 1×1017 cm−3. Semiconductor devices including III-V semiconductors may have a stable normally-off operation.
摘要:
An HEMT type transistor is disclosed that is a normally off type, and in which variations in the gate threshold voltage are small. A transistor is provided with a p-type region, a barrier region, an insulation film, a gate electrode. The channel region is connected to an upper surface of the p-type region. The channel region is n-type or i-type and provided with a first channel region and a second channel region. The barrier region is forming a hetero-junction with an upper surface of the first channel region. The insulation film is connected to an upper surface of the second channel region and an upper surface of the barrier region. The gate electrode faces the second channel region and the barrier region via the insulation film. The first channel region and the second channel region are arranged in series in a current pathway.
摘要:
A HEMT has a drain region adapted to be electrically connected to a high voltage of an electric source, a source region adapted to be electrically connected to a low voltage of the electric source. A first semiconductor region is disposed between the drain region and the source region. A MIS structure and a heterostructure are disposed at a surface of the first semiconductor region. The MIS structure includes a gate electrode that faces a portion of a surface of the first semiconductor region with a gate insulating membrane therebetween. The heterostructure includes a second semiconductor region which makes contact with a rest portion of the surface of the first semiconductor region and has a wider band-gap than the first semiconductor region. The drain region and the source region are capable of being electrically connected with a structure in which the MIS structure 40 and the heterostructure are arranged in series.
摘要:
An SiC semiconductor device includes a substrate, a drift layer, a base region, a source region, a trench, a gate oxide film, a gate electrode, a source electrode and a drain electrode. The substrate has a Si-face as a main surface. The source region has the Si-face. The trench is provided from a surface of the source region to a portion deeper than the base region and extends longitudinally in one direction and has a Si-face bottom. The trench has an inverse tapered shape, which has a smaller width at an entrance portion than at a bottom, at least at a portion that is in contact with the base region.
摘要:
An SiC semiconductor device has a p type region including a low concentration region and a high concentration region filled in a trench formed in a cell region. A p type column is provided by the low concentration region, and a p+ type deep layer is provided by the high concentration region. Thus, since a SJ structure can be made by the p type column and the n type column provided by the n type drift layer, an on-state resistance can be reduced. As a drain potential can be blocked by the p+ type deep layer, at turnoff, an electric field applied to the gate insulation film can be alleviated and thus breakage of the gate insulation film can be restricted. Therefore, the SiC semiconductor device can realize the reduction of the on-state resistance and the restriction of breakage of the gate insulation film.
摘要:
A method of manufacturing a semiconductor device includes forming an ohmic electrode in a first area on one of main surfaces of a silicon carbide layer, siliciding the ohmic electrode, and forming a Schottky electrode in a second area on the one of the main surfaces of the silicon carbide layer with self alignment. The second area is exposed where the ohmic electrode is not formed.
摘要:
The invention provides a method for producing a group III nitride based semiconductor having a reduced number of crystal defects. A GaN layer 2 is epitaxially grown on a sapphire substrate 1 having C-plane as a main plane (FIG. 1A). Then, the layer is wet-etched by use of a 25% aqueous TMAH solution at 85° C. for one hour, to thereby form an etch pit 4 (FIG. 1B) Then, a GaN layer 5 is grown on the GaN layer 2 through the ELO method (FIG. 1C). The thus-formed GaN layer 5 has a screw dislocation density lower than that of the GaN layer 2.
摘要:
A normal person (i.e. a control) and liver diseases such as drug induced liver injury, an asymptomatic hepatitis B carrier, an asymptomatic hepatitis C carrier, chronic hepatitis B, chronic hepatitis C, liver cancer, a nonalcoholic fatty liver disease (NAFLD), nonalcoholic steatohepatitis (NASH), and simple steatosis (SS) are identified by measuring the concentrations of γ-Glu-X (X represents an amino acid or an amine) peptides or the levels of AST or ALT in blood and carrying out, for example, a multiple logistic regression based on the measured value.