LAUSR

Ultra-low-doped mercury cadmium telluride (HgCdTe, or MCT) is of significant interest for infrared detectors designed to suppress Auger recombination. Measurement of low doping levels in multi-layered structures is difficult with traditional 4-point Hall effect measurements. Multi-layered Hg.79Cd.21Te samples were analyzed using variable magnetic field Hall effect measurements and a multi-carrier fitting procedure. The measurements resolve two distinct carrier species corresponding to surface and/or buffer layer conduction and conduction through the primary low-doped material. High-quality electronic transport is achieved, including the demonstration of an epitaxial layer (x = 0.2195) with n = 1.09 × 1014 cm−3 and μ = 275,000 cm2/Vs at 77 K. This technique shows promise as a way to analyze layers with significantly lower doping, and a starting point to understand and advance the development of HgCdTe epilayers with very low doping concentration.