Studies on atomic layer deposition Al2O3/In0.53Ga0.47As interface formation mechanism based on air-gap capacitance-voltage method

摘要

The air-gap capacitance-voltage characteristics of InGaAs surfaces were measured after 1-, 2-, 6-, 9-, and 17-cycle atomic layer deposition (ALD) Al2O3 processing. A high density of mid-gap states was found to be generated and increased during these ALD process steps, while the native oxide component was reduced. On the other hand, the mid-gap state density was drastically reduced after the usual annealing process. The generation of the mid-gap states seemed to be relevant to a non-stoichiometric Al-oxide component associated with a deficit in oxygen atoms, which became re-oxidized during the annealing process.