Abstract:
A silicon carbide semiconductor device (90), includes: 1) a silicon carbide substrate (1); 2) a gate electrode (7) made of polycrystalline silicon; and 3) an ONO insulating film (9) sandwiched between the silicon carbide substrate (1) and the gate electrode (7) to thereby form a gate structure, the ONO insulating film (9) including the followings formed sequentially from the silicon carbide substrate (1): a) a first oxide silicon film (O) (10), b) an SiN film (N) (11), and c) an SiN thermally-oxidized film (O) (12, 12a, 12b). Nitrogen is included in at least one of the following places: i) in the first oxide silicon film (O) (10) and in a vicinity of the silicon carbide substrate (1), and ii) in an interface between the silicon carbide substrate (1) and the first oxide silicon film (O) (10).
Abstract:
An aspect of the present invention provides an ohmic electrode that includes an SiC (silicon carbide) substrate, an impurity region selectively formed in a surface of the SiC substrate, an insulating film formed on the surface of the SiC substrate, a contact hole opened through the insulating film, to expose a surface of the impurity region, a conductive thermal reaction layer formed in the contact hole in contact with the impurity region, a conductive plug formed to fill the contact hole, an metal wiring formed on the insulating film and electrically coupled to the plug, and a diffusion preventive layer formed between the metal wiring and the plug to electrically couple the plug with the metal wiring, the diffusion preventive layer configured to prevent the diffusion of metal atoms from the metal wiring.
Abstract:
In silicon carbide semiconductor device and manufacturing method therefor, a metal electrode which is another than a gate electrode and which is contacted with a singlecrystalline silicon carbide substrate is treated with a predetermined heat process at a temperature which is lower than a thermal oxidization temperature by which a gate insulating film is formed and is sufficient to carry out a contact annealing between the singlecrystalline silicon carbide substrate and a metal after a whole surrounding of the gate insulating film is enclosed with the singlecrystalline silicon carbide substrate, a field insulating film, and the gate electrode. The present invention is applicable to a MOS capacitor, an n channel planar power MOSFET, and an n channel planar power IGBT.
Abstract:
The present invention provides a vehicle navigation system that can customize an optimum route to the driver's road preference. The vehicle navigation system includes at least one data table that contains a set of road data. Each set of road data represents characteristics of one road segment, such as a travel time, a length and a type of the road segment. The navigation system also includes at least one coefficient table that contains a number of coefficients. Each coefficient corresponds to one road segment. In a route search operation, an optimum route is calculated so as to optimize road data that have been modified by weighting the road data by the coefficients. The coefficients are changed based on the user's personal preference on the corresponding road segments. More specifically, a coefficient is penalized when the corresponding road segment that was part of the optimum route was not traveled. On the other hand, a coefficient is credited when the corresponding road segment that was not part of the optimum route was actually traveled.
Abstract:
A ferroelectric thin film is produced on a substrate placed in an oxygen gas atmosphere within a reaction chamber. Evaporated source materials (organic metal compounds) are separately introduced in a predetermined sequence into the reaction chamber to produce a PZT or PLZT layer structure having an estimated stoichiometric composition. This cycle of introduction of the source materials is repeated continuously to produce a PZT or PLZT ferroelectric thin film having a predetermined number of PZT or PLZT layer structures piled on the substrate.
Abstract:
A method for manufacturing a semiconductor device is carried out by readying each of a semiconductor element, a substrate having Cu as a principal element at least on a surface, and a ZnAl solder chip having a smaller shape than that of the semiconductor element; disposing the semiconductor element and the substrate so that respective bonding surfaces face each other, and sandwiching the ZnAl eutectic solder chip between the substrate and the semiconductor element; increasing the temperature of the ZnAl solder chip sandwiched between the substrate and the semiconductor element while applying a load to the ZnAl solder chip such that the ZnAl solder chip melts to form a ZnAl solder layer; and reducing the temperature of the ZnAl solder layer while applying a load to the ZnAl solder layer.
Abstract:
A silicon carbide semiconductor device (90), includes: 1) a silicon carbide substrate (1); 2) a gate electrode (7) made of polycrystalline silicon; and 3) an ONO insulating film (9) sandwiched between the silicon carbide substrate (1) and the gate electrode (7) to thereby form a gate structure, the ONO insulating film (9) including the followings formed sequentially from the silicon carbide substrate (1): a) a first oxide silicon film (O) (10), b) an SiN film (N) (11), and c) an SiN thermally-oxidized film (O) (12, 12a, 12b). Nitrogen is included in at least one of the following places: i) in the first oxide silicon film (O) (10) and in a vicinity of the silicon carbide substrate (1), and ii) in an interface between the silicon carbide substrate (1) and the first oxide silicon film (O) (10).
Abstract:
In this junction element 1, when a forward voltage is applied, a depletion layer is formed in a semiconductor layer 2, prohibiting electrons present in an electrode layer 4 to move into the semiconductor layer 2. For this reason, a majority of holes in a semiconductor layer 3 do not disappear by recombination with conduction electrons in the semiconductor layer 2, but reach the electrode layer 4 while diffusing into the semiconductor layer 2. Accordingly, the junction element 1 can serve as a good conductor for holes, while avoiding the influence of a resistance value, and allows a current to flow therethrough at a level equal to or more than that achieved by a semiconductor element formed of a Si or SiC semiconductor. The present invention is applicable to any semiconductor material in which at least one of a donor level and an acceptor level is located at a sufficiently deep position beyond a thermal excitation energy at an operating temperature, such as diamond, zinc oxide (ZnO), aluminum nitride (AlN), or boron nitride (BN). The present invention is also applicable to even a material having a shallow impurity level at room temperature, such as silicon (Si), silicon carbide (SiC), gallium nitride (GaN), gallium arsenide (GaAs), or germanium (Ge), as long as operation is performed at such a low temperature that the thermal excitation energy can be sufficiently small.
Abstract:
This fuel cell stack includes: a coolant-supplying penetration hole and a coolant-discharging penetration hole each communicating with a coolant passage and each penetrates unit fuel cells in a stacking direction. A coolant-supplying penetration hole and a coolant-discharging penetration hole are arranged in a horizontal direction opposing with each other so as to sandwich a power generating region. The fuel cell stack further includes: an air draining penetration hole communicating with the coolant passage and arranged such that at least one part thereof is located at a higher position than an uppermost position of the coolant passage, and penetrates the unit fuel cells in the stacking direction; and a coolant draining penetration hole communicating with the coolant passage and arranged such that at least one part thereof is located at a lower position than a lowermost position of the coolant passage, and penetrates the unit fuel cells in the stacking direction.
Abstract:
In silicon carbide semiconductor device and manufacturing method therefor, a metal electrode which is another than a gate electrode and which is contacted with a singlecrystalline silicon carbide substrate is treated with a predetermined heat process at a temperature which is lower than a thermal oxidization temperature by which a gate insulating film is formed and is sufficient to carry out a contact annealing between the singlecrystalline silicon carbide substrate and a metal after a whole surrounding of the gate insulating film is enclosed with the singlecrystalline silicon carbide substrate, a field insulating film, and the gate electrode. The present invention is applicable to a MOS capacitor, an n channel planar power MOSFET, and an n channel planar power IGBT.