With the aim of studying the feasibility of sensors using NiTi shape m
emory alloy films, we have realised NiTi/Si(n)/Si(n(+)) structures by
sputter depositing NiTi contacts on Si substrates. The NiTi sputtering
was performed at low substrate temperature (423 K) to avoid the forma
tion of a silicide interfacial layer, Current-voltage (I(V)) measureme
nts on these structures show a rectifying behaviour. The barrier heigh
t and ideality factor were determined from these measurements. The inf
luence of the martensitic phase transformation in the NiTi electrode o
n the electrical properties of the diodes was investigated by recordin
g the I(V) characteristics at various temperatures. This study shows a
n unusual current decrease with increasing temperature above 353 K. Th
e mechanisms responsible for this phenomenon are discussed.