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Technology Profile
Creation of Thermostable Tenzoresistors on
the Base of GaSb-FeGa 1.3, and GaSb-CîGa 1.3
Eutectic Composites
Description
Semiconductor GaSb was made by alloying and refining it
by the method of horizontal recrystallization. Additionally,
GaSb-FeGa1.3 and GaSb-CоGa1.3 eutectic alloys were prepared
by alloying of GaSb with Fe and Co, respectively,
using the vertical Bridgman method. To avoid ampoule vibration
that may disturb the solid-melt interface, the prepared
sample was kept motionless with the movement of
the freezing interface accomplished by lifting the furnace.
The solidified interfaces were planar and oriented perpendicular
to the transport direction on all ingot sections. The
solidification rate was set to about 1mm/min. Employing
this technique, the structure with needle-shaped metallic
FeGa1.3 and CоGa1.3 phase parallel oriented in a specific
direction and uniformly distributed within the GaSb matrix
was obtained. The oriented needles were found to be about
1 μm and 0.5 μm in diameter, 20-150 μm and 10-20μm in
length and with ∼3,3х104mm-2 and 20х104mm-2 density for
inclusions FeGa1.3 and CоGa1.3, respectively. A PhilipsTM FEG scanning electron microscope (SEM) was employed
to characterize the microstructure of the alloys. An energy
dispersive X-ray spectroscopy (EDX) model EDAXTM was
used to obtain quantitative information about the elemental
composition in the matrix, the metal inclusions and the interphase
zone of the samples.
From the grown crystals tenzoresistor elements with the
sizes of 7x0,08x0,2 mm3 were prepared.
Some characteristics of these composites may be adjustable
with change in the size and density of the metallic
inclusions that may be controlled during alloy preparation.
These are important for their use as sensing elements in
optical polarizers, detectors of infrared radiation, tenzoresistors
and so forth.
Innovative Aspects and Main Advantages
Preliminary studies has been showed that the tensorezistors
with linear, thermostable and unhysteresis characteristics
on the base these eutectic composites were obtained;
the temperature coefficient of strain sensitivity factor for
GaSb-CoGa1.3 tenzoresistors was an order less in
comparison with the GaSb-FeGa 1.3 tenzoresistors.
Contact Details
Institute of Physics
Contact person: Almaz Ahmediyya Khalilova
Address: 33, H. Javid Avenue
AZ1143, Baku, Azerbaijan
E-mail: almaz@physics.ab.az
Areas of Application
Measurements of deformation and mechanical stress of
details and constructions in engineering, oil and aircraft industries.
GaSb-FeGa 1.3
Stage of Development
GaSb-CîGa 1.3
Fig.1. Microphotography of GaSb-FeGa1.3 and GaSb-CoGa1.3
eutectic composites along the longitudinal direction of the specimens
(200 times optical magnifications).
Production of tenzoresistors and creation of pressure sensors
- pilot propotypes are available.
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