Quaternary functional semiconductor device-based temperature sensors for low and high temperatures (LTs, HTs)

Abstract

The Al-(ZnCdNiTiO2)-pSi diodes with a ratio of 4;2;2;2 were fabricated and their charge transport mechanisms (CTMs) were investigated between 80-380K and ±4.5 V using current-voltage (IV) measurements. The saturation-current (Is), quality-factor (n), and barrier - height (BH)/(Φbo) values of the diode were calculated from the forward bias ln(IF)-VF curve as function of temperature. While the value of BH is increased, n value is decreased with increasing temperature. Non-linear behavior was observed in the Arrhenius or Richardson plot (RP) (ln(Io/T2) vs q/kT) at low temperatures (LTs). Also, the Richardson - constant (A*) calculated from the linear part of this plot is quite lesser than its theoretical - value (=32 A.(cm.K)-2) for p-Si), and high values of n at LTs show an evident deviated from thermionic - emission (TE) theory. To explain this case; both the nkT/q vs kT/q, Φbo and n vs q/2kT curves were plotted to determine the other possible-CTMs and they show that both the tunneling and Double Gaussian - distribution (DGD) are more effective than TE. The obtained A* value from the modified RP by using the standard deviation from Φbo-q/2kT plot is closer to its theoretical value. The energy dependent curve of interface states or traps (Nss) was calculated from the IF - VF characteristics by considering the voltage dependence of the BH and n for the studied temperature range and they generally decline with increase in temperature due to rearrangement and structure of electrons at traps under the influence of temperature. All these results show that the fabricated Al-(ZnCdNiTiO2)-pSi diode can be used as a temperature - sensor in low and high temperature applications.