Materials Science Forum, Vol.457-460, 755-758, 2004
Non-contact doping profiling in epitaxial SiC
We present a very fast, non-contact and preparation free method of determining doping concentration and doping depths profiles in silicon carbide epitaxial layers. The method is an extension of the recently patented Q(2)-V technique. It uses a corona discharge in air for charging the epi-surface with precisely controlled doses of electrical charge, DeltaQ(C). Corona charging is followed by non-contact measurement of the surface potential, V, using a vibrating probe. A sequence of charging and measuring steps produces the Q(2)-V plot that for uniform doping satisfies a linear relation. For nonuniform doping a depth profile is obtained from a derivative, dQ(2)/dV, similar to the derivative capacitance method.