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arXiv · 1107.5401

Properties and characterization of ALD grown dielectric oxides for MIS structures

S. Gieraltowska·D. Sztenkiel·E. Guziewicz·M. Godlewski·G. Luka·B. S. Witkowski·L. Wachnicki·E. Lusakowska·T. Dietl·M. Sawicki
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Abstract

We report on an extensive structural and electrical characterization of under-gate dielectric oxide insulators Al2O3 and HfO2 grown by Atomic Layer Deposition (ALD). We elaborate the ALD growth window for these oxides, finding that the 40-100 nm thick layers of both oxides exhibit fine surface flatness and required amorphous structure. These layers constitute a base for further metallic gate evaporation to complete the Metal-Insulator-Semiconductor structure. Our best devices survive energizing up to ~3 MV/cm at 77 K with the leakage current staying below the state-of-the-art level of 1 nA. At these conditions the displaced charge corresponds to a change of the sheet carrier density of 3 \times 1013 cm-2, what promises an effective modulation of the micromagnetic properties in diluted ferromagnetic semiconductors.

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S. Gieraltowska, D. Sztenkiel, E. Guziewicz, M. Godlewski, G. Luka, B. S. Witkowski, L. Wachnicki, E. Lusakowska, T. Dietl, M. Sawicki. 2011-07-27. Properties and characterization of ALD grown dielectric oxides for MIS structures. https://arxiv.org/abs/1107.5401

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