The formation of thermochemically stable Schottky barriers on p-Cd0.95Zn0.05Te using Titanium

The electrical properties of Ti-based contacts on p-Cd_0.95Zn_0.05Te (CZT) were investigated. Ti contacts with a Cd or a Te interlayer were produced and compared with the pure Ti contact using current-voltage characteristics (I–V). The barrier heights can be perceived using data on the interface reactions and the phase formation in direct contact with CZT. The percept of the dominating influence of phase formation could be validated for stoichiometric CZT substrate surfaces and also for etched (Te-rich) substrates. It was found that Ti, i.e. the Ti₃Te₄ phase that forms at the interface, produces high barriers in the range of 1 eV. In addition, various Au capped Ti-contacts were investigated. Thermally stable, near-ideal Au/Ti-contacts with a barrier height of 0.76 eV were produced.