Method of manufacturing a planar semiconductor device having a guard ring structure

摘要

A method of manufacturing a semiconductor device of the "planar" type comprising a highly doped substrate having a doping concentration c.sub.o and an epitaxial surface layer having a carrier concentration c c. sub.o, in which are formed a main pn junction having a depth x.sub.j and a structure of floating guard rings. According to the invention, this device also includes between the substrate and the epitaxial surface layer, a second epitaxial layer having a carrier concentration c' such that c.sub.o c' c. This permits the production of devices with different maximum operating voltages using the same configuration of guard rings.