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Title: Ferroelectric properties of full plasma-enhanced ALD TiN/La:HfO{sub 2}/TiN stacks

Abstract

We report the possibility of employment of low temperature (≤330 °C) plasma-enhanced atomic layer deposition for the formation of both electrodes and hafnium-oxide based ferroelectric in the metal-insulator-metal structures. The structural and ferroelectric properties of La doped HfO{sub 2}-based layers and its evolution with the change of both La content (2.1, 3.7 and 5.8 at. %) and the temperature of the rapid thermal processing (550–750 °C) were investigated in detail. Ferroelectric properties emerged only for 2.1 and 3.7 at. % of La due to the structural changes caused by the given doping levels. Ferroelectric properties were also found to depend strongly on annealing temperature, with the most robust ferroelectric response for lowest La concentration and intermediate 650 °C annealing temperature. The long term wake-up effect and such promising endurance characteristics as 3 × 10{sup 8} switches by bipolar voltage cycles with 30 μs duration and ± 3 MV/cm amplitude without any decrease of remnant polarization value were demonstrated.

Authors:
; ; ; ;  [1];  [2]
  1. Moscow Institute of Physics and Technology, Institutskii per. 9, 141700 Dolgoprudny, Moscow Region (Russian Federation)
  2. Technological Institute for Superhard and Novel Carbon Materials, Tsentral'naya Str. 7a, 142190 Troitsk, Moscow (Russian Federation)
Publication Date:
OSTI Identifier:
22590799
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 108; Journal Issue: 24; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABUNDANCE; AMPLITUDES; ANNEALING; DOPED MATERIALS; ELECTRIC POTENTIAL; ELECTRODES; FERROELECTRIC MATERIALS; HAFNIUM OXIDES; LAYERS; PLASMA; POLARIZATION; STACKS; TEMPERATURE RANGE 0400-1000 K; TITANIUM NITRIDES

Citation Formats

Chernikova, A. G., Kuzmichev, D. S., Negrov, D. V., Kozodaev, M. G., Markeev, A. M., and Polyakov, S. N. Ferroelectric properties of full plasma-enhanced ALD TiN/La:HfO{sub 2}/TiN stacks. United States: N. p., 2016. Web. doi:10.1063/1.4953787.
Chernikova, A. G., Kuzmichev, D. S., Negrov, D. V., Kozodaev, M. G., Markeev, A. M., & Polyakov, S. N. Ferroelectric properties of full plasma-enhanced ALD TiN/La:HfO{sub 2}/TiN stacks. United States. doi:10.1063/1.4953787.
Chernikova, A. G., Kuzmichev, D. S., Negrov, D. V., Kozodaev, M. G., Markeev, A. M., and Polyakov, S. N. Mon . "Ferroelectric properties of full plasma-enhanced ALD TiN/La:HfO{sub 2}/TiN stacks". United States. doi:10.1063/1.4953787.
@article{osti_22590799,
title = {Ferroelectric properties of full plasma-enhanced ALD TiN/La:HfO{sub 2}/TiN stacks},
author = {Chernikova, A. G. and Kuzmichev, D. S. and Negrov, D. V. and Kozodaev, M. G. and Markeev, A. M. and Polyakov, S. N.},
abstractNote = {We report the possibility of employment of low temperature (≤330 °C) plasma-enhanced atomic layer deposition for the formation of both electrodes and hafnium-oxide based ferroelectric in the metal-insulator-metal structures. The structural and ferroelectric properties of La doped HfO{sub 2}-based layers and its evolution with the change of both La content (2.1, 3.7 and 5.8 at. %) and the temperature of the rapid thermal processing (550–750 °C) were investigated in detail. Ferroelectric properties emerged only for 2.1 and 3.7 at. % of La due to the structural changes caused by the given doping levels. Ferroelectric properties were also found to depend strongly on annealing temperature, with the most robust ferroelectric response for lowest La concentration and intermediate 650 °C annealing temperature. The long term wake-up effect and such promising endurance characteristics as 3 × 10{sup 8} switches by bipolar voltage cycles with 30 μs duration and ± 3 MV/cm amplitude without any decrease of remnant polarization value were demonstrated.},
doi = {10.1063/1.4953787},
journal = {Applied Physics Letters},
number = 24,
volume = 108,
place = {United States},
year = {Mon Jun 13 00:00:00 EDT 2016},
month = {Mon Jun 13 00:00:00 EDT 2016}
}
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