Identification of Current Transport Mechanisms and Temperature Sensing Qualifications for Al/(ZnS-PVA)/p-Si Structures at Low and Moderate Temperatures

Current transport mechanisms (CTMs) and temperature sensing qualifications of Al/(ZnS-PVA)/
${p}$
-Si structures are identified with the help of temperature-dependent forward bias current-voltage measurements. To determine the current transport mechanism, the electrical parameters of the structure such as saturation current (
${I}_{o}$
), zero – bias barrier height (
$\Phi _{B0}$
), ideality factor (
${n}$
) are determined from these characteristics measured in the temperature range of 60–320 K. The temperature dependencies of the calculated
$\Phi _{\textit {Bo}}$
and
${n}$
values indicate the existence of double Gaussian distribution (DGD) of barrier height (BH) at M/S interface. Using the modified Richardson plots,
$\Phi _{B0}$
and
${A}^{\ast }$
values have been found in the high temperature region (HT) (160-320 K) as 0.95 eV, 31.64 A.cm
⁻²
K
⁻²
, respectively and in the low temperature region (60-140 K) as 0.3871 eV, 20.996 A.cm
⁻²
K
⁻²
, respectively. The
${A}^\ast $
value in the HT region is very close to its theoretical value and hence the CTMs can be explained by the DGD of BH. Sensitivity (
${S}$
) values are calculated for each voltage at forward biases from the temperature-dependent variation of the logarithm of the current (
InI
). A peak value of 7.5 mA/K at 0.5 V was obtained for the sensor with a good linear characteristic and high sensitivity. The results clearly show that the structure can be used successfully and properly as a temperature sensor.