For sequential stacking of an Al 2 O 3 passivation layer and a main HfO 2 gate dielectric layer on In 0.53 Ga 0.47 As, we used single-and dual-temperature atomic-layer deposition processes, and systematically compared their effects on the dielectric-related electrical properties. When the deposition of Al 2 O 3 passivation layer (approximately 0.7−0.8 nm) took place at relatively low temperatures of 100 °C, an increase in the subsequent deposition temperature for HfO 2 (from 100 to 300 °C) assisted in decreasing both capacitance-equivalent oxide thickness and the number of bulk-related traps. However, the valuable reduction in both near-interface defect density and leakage current through the low-temperature Al 2 O 3 passivation approach was monotonically lessened with an increase in the process temperature for the subsequent HfO 2 deposition, which suggests the need for a careful optimization of a thermal budget for the dualtemperature process. Keywords: HfO 2 , Al 2 O 3 , In 0.53 Ga 0.47 As, atomic-layer deposition, dual-temperature process

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In this study, to understand the effect of sublayer thickness of doped HfO2 films with limited dopant solubility on ferroelectric phase stabilization, nanolaminated HfO2–Al2O3 films with various sublayer thicknesses were prepared through atomic layer deposition (ALD), and the phase evolution behavior of these films with increasing post-metallization annealing (PMA) temperature was investigated. A narrow optimal range of the HfO2 sublayer thickness was required to achieve facile crystallization into a tetragonal phase, followed by orthorhombic phase transformation through sufficient Al diffusion. Because the Al2O3 sublayer cannot be completely dissolved, it should be as thin as possible so that it can easily agglomerate to provide an effective connection between the HfO2 sublayers during the PMA process. When stabilizing the ferroelectric phase of HfO2 films by mixing with dopants with limited solubility, the thicknesses of the HfO2 and Al2O3 sublayers in the nanolaminated form were revealed to be more critical than the nominal doping concentration inferred from their thickness ratios (ALD cycle ratios).

To understand the effect of H2S pre-annealing treatment on a Si1−xGex alloy film, the interfacial and electrical characteristics of atomic-layer-deposited HfO2/Si1−xGex were studied while varying the Ge concentration (x value) from 0 to 0.3.

High‐pressure annealing (HPA) in both hydrogen (H2) and deuterium (D2) environments is attempted on HfO2/Si0.7Ge0.3 capacitors as a post‐metallization annealing (PMA) approach. As compared with conventional forming gas annealing (FGA), a dramatic reduction in the interface state density (Dit) is achieved after both H2‐ and D2‐HPA processes at the equivalent temperature (300 °C) and time (30 min) by effectively passivating the Ge‐induced dangling bonds at the interface region. Meanwhile, the stress‐induced leakage current characteristics are only improved by the D2‐HPA process, indicating that D‐passivation is more resistant to external electrical stress than H‐passivation. As the PMA temperature increases to 500 °C, both HPA further decreases the Dit, but a significant increase is observed for FGA. In addition, the PMA temperature‐dependent degradation of leakage current is less in HPA than in FGA.