Low-temperature surface treatments of CdHgTe using the PE-ALD method before HfO$_2$ deposition

The development of methods for surface passivation of narrow-gap semiconductors, in particular CdHgTe, is an actual problem nowadays. One of the promising protective and passivating insulators is hafnium oxide. In this work, the effects of different methods of CdHgTe surface treatment, performed in a plasma-enhanced atomic layer deposition (PE-ALD) system immediately prior to the deposition of HfO$_2$ thin films, on the electrophysical characteristics of the resulting insulator–semiconductor interface are investigated. The values of the built-in charge density and slow trap states have been calculated, and the change of donor concentration in the near-surface region of the semiconductor has been estimated. The chemical composition of the formed intermediate layers was examined.