Semiconductor device with selectively diffused regions

A method of manufacturing a semiconductor device comprising:

• applying a solids-based dopant source to a surface of a semiconducting substrate which is in the shape of a slice;
• diffusing dopant atoms from said solids-based dopant source into said substrate so as to form a first diffusion region in said substrate immediately beneath said solids-based dopant source and a second diffusion region in an area of said substrate not covered by said solids-based dopant source, wherein the surface dopant concentration of said second diffusion region increases with distance from within said second diffusion region towards said first diffusion region;
• and
• forming a metal contact substantially in alignment with said first diffusion region without having etched said second diffusion region substantially.

A method of fabricating a semiconductor device comprising:

• selectively applying a pattern of solids-based dopant source to a first surface of a semiconducting substrate;
• diffusing dopant atoms from said solids-based dopant source into said substrate in a controlled heated gaseous environment, the dopant atoms from said solids-based dopant source diffusing directly into said substrate to form a first diffusion region in said substrate beneath said pattern of said solids-based dopant source and, at the same time, diffusing said dopant atoms from said solids-based dopant source indirectly via said gaseous environment into said substrate to form a second diffusion region in at least some areas of said substrate not covered by said pattern;
• applying a passivating layer on said surface;
• and
• forming a metal contact pattern substantially in alignment with said first diffusion region including sintering through said passivating layer to form ohmic contacts between said metal contact pattern and said first diffusion region.