Publications

Determination of background doping type in type-II superlattice using capacitance-voltage measurements with double mesa structure

Fink, D.R.; Lee, S.; Kodati, S.H.; Dahiya, V.; Ronningen, T.J.; Winslow, M.; Grein, C.H.; Jones, A.H.; Campbell, J.C.; Klem, John F.; Krishna, S.

We present a method of determining the background doping type in semiconductors using capacitance-voltage measurements on overetched double mesa p-i-n or n-i-p structures. Unlike Hall measurements, this method is not limited by the conductivity of the substrate. By measuring the capacitance of devices with varying top and bottom mesa sizes, we were able to conclusively determine which mesa contained the p-n junction, revealing the polarity of the intrinsic layer. This method, when demonstrated on GaSb p-i-n and n-i-p structures, determined that the material is residually doped p-type, which is well established by other sources. The method was then applied on a 10 monolayer InAs/10 monolayer AlSb superlattice, for which the doping polarity was unknown, and indicated that this material is also p-type.