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High-k/InAs interfaces have been manufactured using InAs surface oxygen termination and low temperature atomic layer deposition of HfO2. Capacitance-voltage (C-V) curves revert to essentially classical shape revealing mobile carrier response in accumulation and depletion, hole inversion is observed, and predicted minority carrier response frequency in the hundred kHz range is experimentally confirmed; reference samples using conventional techniques show a trap dominated capacitance response. C-V curves have been fitted using advanced models including nonparabolicity and Fermi-Dirac distribution. For an equivalent oxide thickness of 1.3 nm, an interface state density Dit = 2.2 × 1011 cm-2 eV-1 has been obtained throughout the InAs bandgap. [ABSTRACT FROM AUTHOR]

The performance of InGaAs metal oxide semiconductor field effect transistors with Al2O3 or HfO2 as gate oxide is evaluated and compared. The Al2O3 transistors show the lowest subthreshold slope and mid gap Dit, however, the HfO2 transistors reach a higher maximum transconductance (gmax) due to the higher oxide capacitance. Both high-κ dielectrics show a gm-frequency dispersion due to tunneling into border traps with a negligible activation energy as determined from temperature dependent measurements. The total amount of trapped charge at border traps is lower in the HfO2 devices. Scaling the HfO2 thickness further reduces the gm-frequency dispersion, possibly due to detrapping to the gate electrode. [ABSTRACT FROM AUTHOR]

Thin high-κ oxide films on InAs, formed by atomic layer deposition, are the key to achieve high-speed metal-oxide-semiconductor devices. We have studied the native oxide and the interface between InAs and 2 nm thick Al2O3 or HfO2 layers using synchrotron x-ray photoemission spectroscopy. Both films lead to a strong oxide reduction, obtaining less than 10% of the native As-oxides and between 10% and 50% of the native In-oxides, depending on the deposition temperature. The ratio of native In- to As-oxides is determined to be 2:1. The exact composition and the influence of different oxidation states and suboxides is discussed in detail. [ABSTRACT FROM AUTHOR]

Thin high-κ oxide films on InAs, formed by atomic layer deposition, are the key to achieve high-speed metal-oxide-semiconductor devices. We have studied the native oxide and the interface between InAs and 2 nm thick Al2O3 or HfO2 layers using synchrotron x-ray photoemission spectroscopy. Both films lead to a strong oxide reduction, obtaining less than 10% of the native As-oxides and between 10% and 50% of the native In-oxides, depending on the deposition temperature. The ratio of native In- to As-oxides is determined to be 2:1. The exact composition and the influence of different oxidation states and suboxides is discussed in detail. [ABSTRACT FROM AUTHOR]