Experimental current-voltage-temperature and thermal sensitivity behaviors of an ideal Schottky barrier diode over a wide temperature range

The Pt/epitaxy n-Si/n+Si Schottky barrier diodes (SBDs) with a Schottky contact area of 9 × 10−4 cm2 were fabricated, and their experimental current-voltage (I-V) characteristics exhibited an ideal behavior in the 20–320 K range. We investigated the thermal sensitivity behavior of this SBD, which exhibits an ideal behavior. The series resistance Rs value remained approximately unchanged as 10.00 Ω at 20 K and 9.258 Ω at 320 K. A barrier height value of qΦb0=0.807eV at 320 K shows a slight decrease to 120 K, and the ideality factor n value shows a slight increase from 1.016 at 320 to 1.070 at 120 K. Furthermore, the sharp decrease in qΦb0 value, from 120 to 20 K, was ascribed to the barrier height inhomogeneity due to the low-barrier patches at the Pt/n-Si interface. It has been seen that the forward bias voltage-temperature (V-T) curves for the thermal sensitivity behavior have two linear regions, the low temperature region (LTR) and high temperature region (HTR), at each current level from 1.0 pA to 1.0 mA. The thermal sensitivity coefficient α from the slope of the VT curve increased with a decrease at the current level in both regions. At each current level, the V-T curves give higher α values in the HTR than those in the LTR. The α value ranged from 3.302 mV/K at 1.0 pA to 1.590 mV/K at 1.0 mA in the HTR. As a result, it was concluded that the Pt/n-Si diode can be used as a high-sensitivity thermal diode for sensor applications since its thermal sensitivity values coincide with the literature values.