Abstract: Silicon Carbide (SiC) PiN Diodes are provided having a reverse blocking voltage (VR) from about 3.0 kV to about 10.0 kV and a forward voltage (VF) of less than about 4.3 V.

Abstract: A silicon carbide-based power device includes a silicon carbide drift layer having a planar surface that forms an off-axis angle with a <0001> direction of less than 8°.

Abstract: A silicon carbide-based power device includes a silicon carbide drift layer having a planar surface that forms an off-axis angle with a <0001> direction of less than 8°.

Abstract: A susceptor is disclosed for minimizing or eliminating thermal gradients that affect a substrate wafer during epitaxial growth. The susceptor includes a first susceptor portion including a surface for receiving a semiconductor substrate wafer thereon, and a second susceptor portion facing the substrate receiving surface and spaced from the substrate-receiving surface. The spacing is sufficiently large to permit the flow of gases therebetween for epitaxial growth on a substrate on the surface, while small enough for the second susceptor portion to heat the exposed face of a substrate to substantially the same temperature as the first susceptor portion heats the face of a substrate that is in direct contact with the substrate-receiving surface.

Abstract: Single crystal silicon carbide epitaxial layer on an off-axis substrate are manufactured by placing the substrate in an epitaxial growth reactor, growing a first layer of epitaxial silicon carbide on the substrate, interrupting the growth of the first layer of epitaxial silicon carbide, etching the first layer of epitaxial silicon carbide to reduce the thickness of the first layer, and regrowing a second layer of epitaxial silicon carbide on the first layer of epitaxial silicon carbide. Carrot defects may be terminated by the process of interrupting the epitaxial growth process, etching the grown layer and regrowing a second layer of epitaxial silicon carbide. The growth interruption/etching/regrowth may be repeated multiple times. A silicon carbide epitaxial layer has at least one carrot defect that is terminated within the epitaxial layer.

Abstract: A method is disclosed for preparing a substrate and epilayer for reducing stacking fault nucleation and reducing forward voltage (Vf) drift in silicon carbide-based bipolar devices. The method includes the steps of etching the surface of a silicon carbide substrate with a nonselective etch to remove both surface and subsurface damage, thereafter etching the same surface with a selective etch to thereby develop etch-generated structures from at least any basal plane dislocation reaching the substrate surface that will thereafter tend to either terminate or propagate as threading defects during subsequent epilayer growth on the substrate surface, and thereafter growing a first epitaxial layer of silicon carbide on the twice-etched surface.

Abstract: Silicon Carbide (SiC) PiN Diodes are provided having a reverse blocking voltage (VR) from about 3.0 kV to about 10.0 kV and a forward voltage (VF) of less than about 4.3 V.

Abstract: A method of forming a bipolar device includes forming at least one p-type layer of single crystal silicon carbide and at least one n-type layer of single crystal silicon carbide on a substrate. Stacking faults that grow under forward operation of the device are segregated from at least one of the interfaces between the active region and the remainder of the device. The method of forming bipolar devices includes growing at least one of the epitaxial layers to a thickness greater than the minority carrier diffusion length in that layer. The method also increases the doping concentration of epitaxial layers surrounding the drift region to decrease minority carrier lifetimes therein.

Abstract: Single crystal silicon carbide epitaxial layer on an off-axis substrate are manufactured by placing the substrate in an epitaxial growth reactor, growing a first layer of epitaxial silicon carbide on the substrate, interrupting the growth of the first layer of epitaxial silicon carbide, etching the first layer of epitaxial silicon carbide to reduce the thickness of the first layer, and regrowing a second layer of epitaxial silicon carbide on the first layer of epitaxial silicon carbide. Carrot defects may be terminated by the process of interrupting the epitaxial growth process, etching the grown layer and regrowing a second layer of epitaxial silicon carbide. The growth interruption/etching/regrowth may be repeated multiple times. A silicon carbide epitaxial layer has at least one carrot defect that is terminated within the epitaxial layer.

Abstract: Parasitic deposits are controlled in a deposition system for depositing a film on a substrate, the deposition system of the type defining a reaction chamber for receiving the substrate and including a process gas in the reaction chamber and an interior surface contiguous with the reaction chamber. Such control is provided by flowing a buffer gas between the interior surface and at least a portion of the process gas to form a gas barrier layer such that the gas barrier layer inhibits contact between the interior surface and components of the process gas. A deposition system for depositing a film on a substrate using a process gas includes a reaction chamber adapted to receive the substrate and the process gas. The system further includes an interior surface contiguous with the reaction chamber.

Abstract: A method for locally controlling the stoichiometry of an epitaxially deposited layer on a semiconductor substrate is provided. The method includes directing a first reactant gas and a doping gas across a top surface of a semiconductor substrate and directing a drive gas and a second reactant gas against the substrate separately from the first reactant gas in a manner that rotates the substrate while introducing the second reactant gas at an edge of the substrate to control each reactant separately, thereby compensating and controlling depletion effects and improving doping uniformity in resulting epitaxial layers on the substrate.

Abstract: An epitaxial silicon carbide layer is fabricated by forming first features in a surface of a silicon carbide substrate having an off-axis orientation toward a crystallographic direction. The first features include at least one sidewall that is orientated nonparallel (i.e., oblique or perpendicular) to the crystallographic direction. A first epitaxial silicon carbide layer is then grown on the surface of the silicon carbide substrate that includes first features therein. Second features are then formed in the first epitaxial layer. The second features include at least one sidewall that is oriented nonparallel to the crystallographic direction. A second epitaxial silicon carbide layer is then grown on the surface of the first epitaxial silicon carbide layer that includes the second features therein.

Abstract: A method for controlling parasitic deposits in a deposition system for depositing a film on a substrate, the deposition system defining a reaction chamber for receiving the substrate and including a process gas in the reaction chamber and an interior surface contiguous with the reaction chamber, includes flowing a buffer gas between the interior surface and at least a portion of the process gas to form a gas barrier layer such that the gas barrier layer inhibits contact between the interior surface and components of the process gas.

Abstract: An epitaxial silicon carbide layer is fabricated by forming first features in a surface of a silicon carbide substrate having an off-axis orientation toward a crystallographic direction. The first features include at least one sidewall that is orientated nonparallel (i.e., oblique or perpendicular) to the crystallographic direction. A first epitaxial silicon carbide layer is then grown on the surface of the silicon carbide substrate that includes first features therein. Second features are then formed in the first epitaxial layer. The second features include at least one sidewall that is oriented nonparallel to the crystallographic direction. A second epitaxial silicon carbide layer is then grown on the surface of the first epitaxial silicon carbide layer that includes the second features therein.

Abstract: A method of forming a bipolar device includes forming at least one p-type layer of single crystal silicon carbide and at least one n-type layer of single crystal silicon carbide on a substrate. Stacking faults that grow under forward operation of the device are segregated from at least one of the interfaces between the active region and the remainder of the device. The method of forming bipolar devices includes growing at least one of the epitaxial layers to a thickness greater than the minority carrier diffusion length in that layer. The method also increases the doping concentration of epitaxial layers surrounding the drift region to decrease minority carrier lifetimes therein.

Abstract: A bipolar device has at least one p?type layer of single crystal silicon carbide and at least one n?type layer of single crystal silicon carbide, wherein those portions of those stacking faults that grow under forward operation are segregated from at least one of the interfaces between the active region and the remainder of the device.

Abstract: Methods of forming high voltage silicon carbide power devices utilize high purity silicon carbide drift layers that are derived from high purity silicon carbide wafer material, instead of prohibitively costly epitaxially grown silicon carbide layers. The methods include forming both minority carrier and majority carrier power devices that can support greater than 10 kV blocking voltages, using drift layers having thicknesses greater than about 100 um. The drift layers are formed as boule-grown silicon carbide drift layers having a net n-type dopant concentration therein that is less than about 2×1015 cm?3. These n-type dopant concentrations can be achieved using neutron transmutation doping (NTD) techniques.

Abstract: A method is disclosed for preparing a substrate and epilayer for reducing stacking fault nucleation and reducing forward voltage (Vf) drift in silicon carbide-based bipolar devices. The method includes the steps of etching the surface of a silicon carbide substrate with a nonselective etch to remove both surface and sub-surface damage, thereafter etching the same surface with a selective etch to thereby develop etch-generated structures from at least any basal plane dislocation reaching the substrate surface that will thereafter tend to either terminate or propagate as threading defects during subsequent epilayer growth on the substrate surface, and thereafter growing a first epitaxial layer of silicon carbide on the twice-etched surface.

Abstract: A susceptor is disclosed for minimizing or eliminating thermal gradients that affect a substrate wafer during epitaxial growth. The susceptor comprises a first susceptor portion including a surface for receiving a semiconductor substrate wafer thereon, and a second susceptor portion facing the substrate-receiving surface and spaced from the substrate-receiving surface. The spacing is sufficiently large to permit the flow of gases therebetween for epitaxial growth on a substrate on the surface, while small enough for the second susceptor portion to heat the exposed face of a substrate to substantially the same temperature as the first susceptor portion heats the face of a substrate that is in direct contact with the substrate-receiving surface.

Abstract: A susceptor is disclosed for minimizing or eliminating thermal gradients that affect a substrate wafer during epitaxial growth. The susceptor comprises a first susceptor portion including a surface for receiving a semiconductor substrate wafer thereon, and a second susceptor portion facing the substrate-receiving surface and spaced from the substrate-receiving surface. The spacing is sufficiently large to permit the flow of gases therebetween for epitaxial growth on a substrate on the surface, while small enough for the second susceptor portion to heat the exposed face of a substrate to substantially the same temperature as the first susceptor portion heats the face of a substrate that is in direct contact with the substrate-receiving surface.