Comparative analysis of microwave low-barrier Mott and Schottky detector diodes

The effect of active layer homogeneous doping in a low-barrier metal-semiconductor contact with near-surface delta-doping on current and capacitance characteristics have been investigated. Difference in characteristics of diodes with Mott and Schottky contacts develops with increasing doping, which results in partial active layer depletion. For really important thickness of an active layer in microwave diodes this concentration can be estimated as 10¹⁵ cm^-3. Exceeding of this doping level leads to increase of reverse current, decrease current nonlinearity and growth of contact capacitance. This results in reduced volt-watt sensitivity for a detector with low-barrier Schottky diodes comparing with Mott diodes.