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In 0.53 Ga 0.47 As p + n diodes with different densities of extended defects have been analyzed by detailed structural and electrical characterization. The defects have been introduced during Metal-Organic Vapor Phase Epitaxy (MOVPE) growth by using a lattice-mismatched layer on a semi-insulating InP or GaAs substrate. The residual strain and indium content in the n-type In 0.53 Ga 0.47 As layer have been determined by high-resolution X-ray diffraction, showing nearly zero strain and a fixed indium ratio of 0.53. The deep levels in the layer have been characterized by Deep Level Transient Spectroscopy. The mean value of electron traps at 0.17 ± 0.03 eV below the conduction band minimum E C is assigned to the "localized" states of α 60°misfit dislocations; another broad electron trap with mean activation energies between E C − 0.17 ± 0.01 and 0.39 ± 0.04 eV, is identified as threading dislocation segments with "band-like" states. A high variation of the pre-exponential factor K T by 7 orders of magnitude is found for the latter when changing the filling pulse time, which can be explained by the coexistence of acceptor-like and donor-like states in the core of split dislocations in III-V materials. Furthermore, two hole traps at E V + 0.42 ± 0.01 and E V + 0.26 ± 0.13 eV are related to the double acceptor of the Ga(In) vacancy (V Ga/In 3-/2-) and 60°β misfit dislocations, respectively. Finally, the dislocation climbing mechanism and the evolution of the antisite defects As Ga/In are discussed for n-type In 0.53 Ga 0.47 As.

We present a comprehensive study of Positive Bias Temperature Instability (PBTI) in In 0.53 Ga 0.47 As devices with Al 2 O 3 gate oxide, and with varying thickness of the channel quantum well. We show significant instability of the device electrical parameters induced by electron trapping into a wide distribution of defects in the high-k layer, with energy levels just above the InGaAs conduction band. A significant PBTI dependence on the channel thickness is found and ascribed to quantization effects. We argue that, in order to be relevant for production, the superior transport properties of III-V channels will need to be demonstrated with more stable high-k gate stacks.

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We investigated the passivation of In0.53Ga0.47As (001) surface by molecular beam epitaxy techniques. After growth of strained In0.53Ga0.47As on InP (001) substrate, HfO2/Al2O3 high-κ oxide stacks have been deposited in-situ after surface reconstruction engineering. Excellent capacitance-voltage characteristics have been demonstrated along with low gate leakage currents. The interfacial density of states (Dit) of the Al2O3/In0.53Ga0.47As interface have been revealed by conductance measurement, indicating a downward Dit profile from the energy close to the valence band (medium 1012 cm−2eV−1) towards that close to the conduction band (1011 cm−2eV−1). The low Dit’s are in good agreement with the high Fermi-level movement efficiency of greater than 80%. Moreover, excellent scalability of the HfO2 has been demonstrated as evidenced by the good dependence of capacitance oxide thickness on the HfO2 thickness (dielectric constant of HfO2 ∼20) and the remained low Dit’s due to the thin Al2O3 passivation layer. The sample with HfO2 (3.4 nm)/Al2O3 (1.2 nm) as the gate dielectrics has exhibited an equivalent oxide thickness of ∼0.93 nm.