Method of manufacturing a semiconductor device utilizing outdiffusion to

Abstract

A method of manufacturing a semiconductor device having two juxtaposed regions (12, 16) of opposite conductivity types which adjoin a surface and which together constitute a p-n junction (9) which is preferably perpendicular to the surface and the doping concentration of which decreases towards the surface. According to the invention n-type and p-type buried layers (2, 6) are provided beside each other on a semiconductor substrate (1) and on said layers a high-ohmic epitaxial layer (7) is grown. By heating, the dopants diffuse from the buried layers through the whole thickness of the epitaxial layer and into the substrate. With suitably chosen donor and acceptor atoms (for example boron and phosphorus in silicon) n and p-type regions (12, 16) are formed in the epitaxial layer and form a p-n junction (9) perpendicular to the surface by compensation of the lateral diffusions from the buried layers.