Abstract: The method described herein enables the introduction of external impurities into Silicon Carbide (SiC) to be conducted at a temperature between 1150-1400° C. Advantages include: a) low temperature diffusion procedure with greater control of the doping process, b) prevent roughness of SiC surface, c) less surface defects and d) better device performance and higher yield. The method described herein involves depositing a ceramic layer that contains the desired impurity and a certain element such as oxygen (in the form of oxide), or other elements/compounds that draw out the silicon and carbon atoms from the surface region of the SiC leaving behind carbon and silicon vacancies which then allow the external impurity to diffuse into the SiC more easily. In another embodiment, the deposited layer also has carbon atoms that discourage carbon from escaping from the SiC, thus generating a surface region of excess carbon in addition to the silicon vacancies.

Abstract: In one aspect the present invention provides a method for manufacturing a silicon carbide semiconductor device. A layer of silicon dioxide is formed on a silicon carbide substrate and nitrogen is incorporated at the silicon dioxide/silicon carbide interface. In one embodiment, nitrogen is incorporated by annealing the semiconductor device in nitric oxide or nitrous oxide. In another embodiment, nitrogen is incorporated by annealing the semiconductor device in ammonia.

Abstract: The method described herein enables the introduction of external impurities into Silicon Carbide (SiC) to be conducted at a temperature between 1150-1400° C. Advantages include: a) low temperature diffusion procedure with greater control of the doping process, b) prevent roughness of SiC surface, c) less surface defects and d) better device performance and higher yield. The method described herein involves depositing a ceramic layer that contains the desired impurity and a certain element such as oxygen (in the form of oxide), or other elements/compounds that draw out the silicon and carbon atoms from the surface region of the SiC leaving behind carbon and silicon vacancies which then allow the external impurity to diffuse into the SiC more easily. In another embodiment, the deposited layer also has carbon atoms that discourage carbon from escaping from the SiC, thus generating a surface region of excess carbon in addition to the silicon vacancies.

Abstract: In one aspect the present invention provides a method for manufacturing a silicon carbide semiconductor device. A layer of silicon dioxide is formed on a silicon carbide substrate and nitrogen is incorporated at the silicon dioxide/silicon carbide interface. In one embodiment, nitrogen is incorporated by annealing the semiconductor device in nitric oxide or nitrous oxide. In another embodiment, nitrogen is incorporated by annealing the semiconductor device in ammonia. In another aspect, the present invention provides a silicon carbide semiconductor device that has a 4H-silicon carbide substrate, a layer of silicon dioxide disposed on the 4H-silicon carbide substrate and a region of substantial nitrogen concentration at the silicon dioxide/silicon carbide interface.

Abstract: In one aspect the present invention provides a method for manufacturing a silicon carbide semiconductor device. A layer of silicon dioxide is formed on a silicon carbide substrate and nitrogen is incorporated at the silicon dioxide/silicon carbide interface. In one embodiment, nitrogen is incorporated by annealing the semiconductor device in nitric oxide or nitrous oxide. In another embodiment, nitrogen is incorporated by annealing the semiconductor device in ammonia. In another aspect, the present invention provides a silicon carbide semiconductor device that has a 4H-silicon carbide substrate, a layer of silicon dioxide disposed on the 4H-silicon carbide substrate and a region of substantial nitrogen concentration at the silicon dioxide/silicon carbide interface.

Abstract: In one aspect the present invention provides a method for manufacturing a silicon carbide semiconductor device. A layer of silicon dioxide is formed on a silicon carbide substrate and nitrogen is incorporated at the silicon dioxide/silicon carbide interface. In one embodiment, nitrogen is incorporated by annealing the semiconductor device in nitric oxide or nitrous oxide. In another embodiment, nitrogen is incorporated by annealing the semiconductor device in ammonia. In another aspect, the present invention provides a silicon carbide semiconductor device that has a 4H-silicon carbide substrate, a layer of silicon dioxide disposed on the 4H-silicon carbide substrate and a region of substantial nitrogen concentration at the silicon dioxide/silicon carbide interface.

Abstract: A method for manufacturing a silicon carbide semiconductor device. In one embodiment, the method includes the following steps: a layer of silicon dioxide is formed on a silicon carbide substrate to create a silicon dioxide/silicon carbide interface and then nitrogen is incorporated at the silicon dioxide/silicon carbide interface for reduction in an interface trap density. The silicon carbide substrate, in one embodiment, includes a n-type 4H-silicon carbide.