The a-SiC/c-Si(n) isotype heterojunction has been studied
as a temperature sensor by measuring its reverse current-voltage
(IR−V)
and reverse voltage-temperature (V-T)
characteristics, as well as its reverse current temperature
dependence. The IR−V
characteristics exhibit an almost constant
current, whereas the reverse current IR depends strongly on T
(from 230 K up to 320K). The V-T characteristics, at
different reverse currents, reveal a highly temperature sensitive
behavior for the a-SiC/c-Si(n) junction. The measured
values of temperature sensitivity (Δ V/ΔT)max was found to be
(≅−2.5 V/K) in the moderate temperature range, which are
much higher than those obtained with bulk semiconductor
temperature sensors. The high sensitivity-temperature- range of
the a-SiC/c-Si(n) heterojunctions can be controlled
electrically within the regim of values from 230 K up to 320 K.
Finally, the high sensitivity of these devices, in conjunction
with the fact that a-SiC films can be used as an add-on to the
existing Si technology, emerge new possibilities to the
fabrication of high sensitivity temperature microsensors.