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Title: Examination of the temperature dependent electronic behavior of GeTe for switching applications

Abstract

The DC and RF electronic behaviors of GeTe-based phase change material switches as a function of temperature, from 25 K to 375 K, have been examined. In its polycrystalline (ON) state, GeTe behaved as a degenerate p-type semiconductor, exhibiting metal-like temperature dependence in the DC regime. This was consistent with the polycrystalline (ON) state RF performance of the switch, which exhibited low resistance S-parameter characteristics. In its amorphous (OFF) state, the GeTe presented significantly greater DC resistance that varied considerably with bias and temperature. At low biases (<1 V) and temperatures (<200 K), the amorphous GeTe low-field resistance dramatically increased, resulting in exceptionally high amorphous-polycrystalline (OFF-ON) resistance ratios, exceeding 10{sup 9} at cryogenic temperatures. At higher biases and temperatures, the amorphous GeTe exhibited nonlinear current-voltage characteristics that were best fit by a space-charge limited conduction model that incorporates the effect of a defect band. The observed conduction behavior suggests the presence of two regions of localized traps within the bandgap of the amorphous GeTe, located at approximately 0.26–0.27 eV and 0.56–0.57 eV from the valence band. Unlike the polycrystalline state, the high resistance DC behavior of amorphous GeTe does not translate to the RF switch performance; instead, a parasitic capacitance associated with the RF switch geometrymore » dominates OFF state RF transmission.« less

Authors:
; ;  [1]; ; ; ; ;  [2]
  1. Naval Research Laboratory, Washington, DC 20375 (United States)
  2. Northrop Grumman Electronics Systems, Linthicum, Maryland 21090 (United States)
Publication Date:
OSTI Identifier:
22596829
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; 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; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CAPACITANCE; CRYOGENICS; DEFECTS; GEOMETRY; GERMANIUM TELLURIDES; METALS; NONLINEAR PROBLEMS; PERFORMANCE; PHASE CHANGE MATERIALS; POLYCRYSTALS; P-TYPE CONDUCTORS; SPACE CHARGE; SWITCHES; TEMPERATURE DEPENDENCE; VALENCE

Citation Formats

Champlain, James G., Ruppalt, Laura B., Guyette, Andrew C., El-Hinnawy, Nabil, Borodulin, Pavel, Jones, Evan, Young, Robert M., and Nichols, Doyle. Examination of the temperature dependent electronic behavior of GeTe for switching applications. United States: N. p., 2016. Web. doi:10.1063/1.4954313.
Champlain, James G., Ruppalt, Laura B., Guyette, Andrew C., El-Hinnawy, Nabil, Borodulin, Pavel, Jones, Evan, Young, Robert M., & Nichols, Doyle. Examination of the temperature dependent electronic behavior of GeTe for switching applications. United States. doi:10.1063/1.4954313.
Champlain, James G., Ruppalt, Laura B., Guyette, Andrew C., El-Hinnawy, Nabil, Borodulin, Pavel, Jones, Evan, Young, Robert M., and Nichols, Doyle. 2016. "Examination of the temperature dependent electronic behavior of GeTe for switching applications". United States. doi:10.1063/1.4954313.
@article{osti_22596829,
title = {Examination of the temperature dependent electronic behavior of GeTe for switching applications},
author = {Champlain, James G. and Ruppalt, Laura B. and Guyette, Andrew C. and El-Hinnawy, Nabil and Borodulin, Pavel and Jones, Evan and Young, Robert M. and Nichols, Doyle},
abstractNote = {The DC and RF electronic behaviors of GeTe-based phase change material switches as a function of temperature, from 25 K to 375 K, have been examined. In its polycrystalline (ON) state, GeTe behaved as a degenerate p-type semiconductor, exhibiting metal-like temperature dependence in the DC regime. This was consistent with the polycrystalline (ON) state RF performance of the switch, which exhibited low resistance S-parameter characteristics. In its amorphous (OFF) state, the GeTe presented significantly greater DC resistance that varied considerably with bias and temperature. At low biases (<1 V) and temperatures (<200 K), the amorphous GeTe low-field resistance dramatically increased, resulting in exceptionally high amorphous-polycrystalline (OFF-ON) resistance ratios, exceeding 10{sup 9} at cryogenic temperatures. At higher biases and temperatures, the amorphous GeTe exhibited nonlinear current-voltage characteristics that were best fit by a space-charge limited conduction model that incorporates the effect of a defect band. The observed conduction behavior suggests the presence of two regions of localized traps within the bandgap of the amorphous GeTe, located at approximately 0.26–0.27 eV and 0.56–0.57 eV from the valence band. Unlike the polycrystalline state, the high resistance DC behavior of amorphous GeTe does not translate to the RF switch performance; instead, a parasitic capacitance associated with the RF switch geometry dominates OFF state RF transmission.},
doi = {10.1063/1.4954313},
journal = {Journal of Applied Physics},
number = 24,
volume = 119,
place = {United States},
year = 2016,
month = 6
}
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