Structural and magnetic studies on Ni(Co)MnIn thin
films
Rohit Singh1, Babita Ingale1, Ratnamala Chatterjee1*
1
Magnetics and Advanced Cermaics Laboratory, Physics Department, Indian Institute of Technology Delhi, Hauz
Khas, New Delhi-110016
*
Corresponding author’s e-mail: rmala@physics.iitd.ac.in, Tel.: +91-2659-1354; Fax: +91-2658-1114
Abstract
Synthesis and detailed structural and magnetic studies
on Ni(Co)MnIn thin films have been reported. Room
temperature X-ray diffraction data shows the presence of
both cubic and orthorhombic structure. The compositions
of the samples have been identified from EDX studies.
Thermomagnetization studies show the metamagnetic
transformation at around 250 K.
Keywords: Thin film, RF magnetron sputtering, Heusler alloy,
Ni-Co-Mn-In alloy, Metamagnetic transition, Shape memory
alloy.
both austenite L21 phase and martensite orthorhombic
phase
at
room
temperature
[2].
The
thermomagnetization curve (M vs T) have been
performed at different magnetic fields like 1 kOe, 10
kOe, 50 kOe. The M vs T data, the transformation
occurs from martensite phase of low magnetic moment
to austenite phase of high magnetic moment and also
the martensitic transformation temperatures decreases
with increasing field, which shows that this
transformation is of metamagnetic type [1].
Introduction
Synthesis and characterization
The Ni(Co)MnIn thin films were deposited
onto Si (100) substrates by magnetron sputtering. A
circular disc of Ni45Co5Mn36.6In13.4 (with 4N purity of
Ni, Co, Mn, In elements) was used as the target. The
radio frequency power, ambient pressure of argon gases,
and substrate temperature were set at 120 W, 3.2 x 10-2
mbar, and 650 °C, respectively. The deposition time
was 1, 2, or 3 h. As-deposited thin films were annealed
in vacuum at 700 °C. The crystalline structure of
Ni(Co)MnIn thin films were determined using grazing
incident angle XRD (PANalytical X’Pert PRO). The
incident angle of X-ray was fixed at 0.5°. The magnetic
measurements were performed in SQUID magnetometer
in temperature range (2 K ≤ T ≤ 395 K) and field range
(100 Oe ≤ H ≤ 70 kOe).
Result and discussion
Crystal structure was identified from X-ray
diffraction data. The X-ray data contains the peaks of
0
(002)14M
Vacuum annealed at 700 C
(004)A/(040)14M
Ni(Co)MnIn
(331)A
(220)A
Intensity (arb. unit)
The Heusler alloys with Ni-Mn-X, X=Al, In,
Sb shows the magnetostructural transformation from a
low temperature martensite phase to a high temperature
parent phase. The partial substitutions of Co at the place
of Ni changes the magnetic properties of parent phase
drastically and make them as the candidate for
metamagnetic shape memory effect [1]. With the
composition Ni(Co)MnX these alloys shows very
interesting properties like Giant magnetoresistance,
kinetic arrest, Magnetocaloric effect and exchange bias
etc. which make them useful for various device
applications like sensors, actuators, refrigerators,
recording media, etc.
20
30
40
50
60
70
80
90
2degree)
Fig. 1: Room temperature X-ray diffraction data for
Ni(Co)MnIn thin film.
Conclusions
Thin films of Ni(Co)MnIn quaternary alloys
deposited on the Si(100)-substrates. Crystal structure
was identified by room temperature X-ray diffraction
data that shows presence of both austenite L21 and
martenstie orthorhombic. The thermomagnetization
measurements at different magnetic fields confirm the
metamagnetism in the thin film sample.
Acknowledgment
SQUID magnetometer facility at IIT Delhi is
acknowledged. One of the author, R.S. would like to
acknowledge CSIR, India for providing fellowship.
References
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Khovaylo, L.K. Varga, and R. Chatterjee, J. Appl.
Phys. 114, (2013), 243911.
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Fähler, Appl. Phys. Lett. 97, (2010), 222507.
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Phys. 111, (2012), 093909.