Patent application number | Description | Published |
20090045413 | Silicon Carbide Bipolar Semiconductor Device - In a SiC bipolar semiconductor device with a mesa structure having a SiC drift layer of a first conductive type and a SiC carrier injection layer of a second conductive type that are SiC epitaxial layers grown from a surface of a SiC single crystal substrate, the formation of stacking faults and the expansion of the area thereof are prevented and thereby the increase in forward voltage is prevented. Further, a characteristic of withstand voltage in a reverse biasing is improved. An forward-operation degradation preventing layer is formed on a mesa wall or on a mesa wall and a mesa periphery to separate spatially the surface of the mesa wall from a pn-junction interface. In one embodiment, the forward-operation degradation preventing layer is composed of a silicon carbide low resistance layer of a second conductive type that is equipotential during the application of a reverse voltage. In another embodiment, the forward-operation degradation preventing layer is composed of a silicon carbide conductive layer of a second conductive type, and a metal layer that is equipotential during the application of a reverse voltage is formed on a surface of the silicon carbide conductive layer. In still another embodiment, the forward-operation degradation preventing layer is composed of a high resistance amorphous layer. | 02-19-2009 |
20090096053 | Schottky Barrier Semiconductor Device and Method for Manufacturing the Same - A silicon carbide Schottky barrier semiconductor device provided with a Ta electrode as a Schottky electrode, in which the Schottky barrier height is controlled to a desired value in a range where power loss is minimized without increasing the n factor. The method for manufacturing the silicon carbide Schottky barrier semiconductor device includes the steps of depositing Ta on a crystal face of an n-type silicon carbide epitaxial film, the crystal face having an inclined angle in the range of 0° to 10° from a (000-1) C face, and carrying out a thermal treatment at a temperature range of 300 to 1200° C. to form the Schottky electrode. | 04-16-2009 |
20090195296 | Method for Recovering an On-State Forward Voltage and, Shrinking Stacking Faults in Bipolar Semiconductor Devices, and the Bipolar Semiconductor Devices - In a bipolar semiconductor device such that electrons and holes are recombined in a silicon carbide epitaxial film grown from the surface of a silicon carbide single crystal substrate at the time of on-state forward bias operation; an on-state forward voltage increased in a silicon carbide bipolar semiconductor device is recovered by shrinking the stacking fault area enlarged by on-state forward bias operation. In a method of this invention, the bipolar semiconductor device in which the stacking fault area enlarged and the on-state forward voltage has been increased by on-state forward bias operation, is heated at a temperature of higher than 350° C. | 08-06-2009 |
20090243026 | Schottky Barrier Diode and Method for Using the Same - An intermediate metal film is formed between a Schottky electrode and a pad electrode. A Schottky barrier height between the intermediate metal film and a silicon carbide epitaxial film is equivalent to or higher than a Schottky barrier height between the Schottky electrode and the silicon carbide epitaxial film. By this configuration, an excess current and a leak current through a pin-hole can be suppressed even in the case in which a Schottky barrier height between the pad electrode and the silicon carbide epitaxial film is less than the Schottky barrier height between the Schottky electrode and the silicon carbide epitaxial film. | 10-01-2009 |
20090317983 | Process for Producing Silicon Carbide Semiconductor Device - In a bipolar silicon carbide semiconductor device in which an electron and a hole recombine with each other during current passage within a silicon carbide epitaxial film grown from a surface of a silicon carbide single crystal substrate, an object described herein is the reduction of defects which are the nuclei of a stacking fault which is expanded by current passage, thereby suppressing the increase of the forward voltage of the bipolar silicon carbide semiconductor device. In a method for producing a bipolar silicon carbide semiconductor device, the device is subjected to a thermal treatment at a temperature of 300° C. or higher in the final step of production. Preferably, the above-mentioned thermal treatment is carried out after the formation of electrodes and then the resulting bipolar silicon carbide semiconductor device is mounted in a package. | 12-24-2009 |
20120325138 | FILM-FORMING APPARATUS AND FILM-FORMING METHOD - A film-forming apparatus and method comprising a film-forming chamber for supplying a reaction gas into, a cylindrical shaped liner provided between an inner wall of the film-forming chamber and a space for performing a film-forming process, a main-heater for heating a substrate placed inside the liner, from the bottom side, a sub-heater cluster provided between the liner and the inner wall, for heating the substrate from the top side, wherein the main-heater and the sub-heater cluster are resistive heaters, wherein the sub-heater cluster has a first sub-heater provided at the closest position to the substrate, and a second sub-heater provided above the first sub-heater, wherein the first sub-heater heats the substrate in combination with the main-heater, the second sub-heater heats the liner at a lower output than the first sub-heater, wherein each temperature of the main-heater, the first sub-heater, and the second sub-heater is individually controlled. | 12-27-2012 |
20130247816 | FILM-FORMING APPARATUS FOR THE FORMATION OF SILICON CARBIDE AND FILM-FORMING METHOD FOR THE FORMATION OF SILICON CARBIDE - A film-forming apparatus and method for the formation of silicon carbide comprising, a film-forming chamber to which a reaction gas is supplied, a temperature-measuring unit which measures a temperature within the chamber, a plurality of heating units arranged inside the chamber, an output control unit which independently controls outputs of the plurality of heating units, a substrate-transferring unit which transfers a substrate into, and out of the chamber, wherein the output control unit turns off or lowers at least one output of the plurality of heating units when the film forming process is completed, when the temperature measured by the temperature-measuring unit reaches a temperature at which the substrate-transferring unit is operable within the chamber, then at least one output of the plurality of heating units turned off or lowered, is turned on or raised, and the substrate is transferred out of the film-forming chamber by the substrate-transferring unit. | 09-26-2013 |
20150214306 | SEMICONDUCTOR STRUCTURE, SEMICONDUCTOR DEVICE, AND METHOD FOR PRODUCING SEMICONDUCTOR STRUCTURE - The present invention provides a semiconductor structure which includes at least a p-type silicon carbide single crystal layer having an α-type crystal structure, containing aluminum at impurity concentration of 1×10 | 07-30-2015 |