Ohmic contacts of Au and Ag metals to n-type GdN thin films

Felicia Ullstad; Jay R. Chan; Harry Warring; Natalie Plank; Ben Ruck; Joe Trodahl; Franck Natali; Felicia Ullstad; Jay R. Chan; Harry Warring; Natalie Plank; Ben Ruck; Joe Trodahl; Franck Natali

doi:10.3934/matersci.2015.2.79

AIMS Materials Science

2015, Volume 2, Issue 2: 79-85. doi: 10.3934/matersci.2015.2.79

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Ohmic contacts of Au and Ag metals to n-type GdN thin films

The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, PO Box 600, Wellington, New Zealand

Received: 28 February 2015 Accepted: 29 April 2015 Published: 07 May 2015

The rare-earth nitrides appear as attractive alternatives to dilute ferromagnetic semiconductors for spintronics device applications. Most of them combine the properties of the ferromagnet and the semiconductor, an exceedingly rare combination. In this work we have grown n-type polycrystalline semiconducting GdN layers between pre-deposited contacts made of Cr/Au and Cr/Ag. The resistivity of the GdN layers ranges from 4.4×10^-4 Ωcm to 3.1×10^-2 Ωcm depending on the nitrogen pressure during the growth. The electrical properties of metal/n-type GdN/metal planar junctions are investigated as a function of the temperature. The current voltage characteristics of the junctions were linear for temperatures ranging from 300 K down to 5 K, suggesting an ohmic contact between the Au or Ag metal and the n-type GdN layer.
- rare-earth nitrides,
- GdN,
- spintronics,
- planar heterojunctions
Citation: Felicia Ullstad, Jay R. Chan, Harry Warring, Natalie Plank, Ben Ruck, Joe Trodahl, Franck Natali. Ohmic contacts of Au and Ag metals to n-type GdN thin films[J]. AIMS Materials Science, 2015, 2(2): 79-85. doi: 10.3934/matersci.2015.2.79

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Abstract

The rare-earth nitrides appear as attractive alternatives to dilute ferromagnetic semiconductors for spintronics device applications. Most of them combine the properties of the ferromagnet and the semiconductor, an exceedingly rare combination. In this work we have grown n-type polycrystalline semiconducting GdN layers between pre-deposited contacts made of Cr/Au and Cr/Ag. The resistivity of the GdN layers ranges from 4.4×10^-4 Ωcm to 3.1×10^-2 Ωcm depending on the nitrogen pressure during the growth. The electrical properties of metal/n-type GdN/metal planar junctions are investigated as a function of the temperature. The current voltage characteristics of the junctions were linear for temperatures ranging from 300 K down to 5 K, suggesting an ohmic contact between the Au or Ag metal and the n-type GdN layer.

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