Abstract:The current-voltage characteristics of a PtSi/p-Si Schottky barrier diode was measured at the temperature of 85 K and from the forward bias region of the I-V curve, the electrical parameters of the diode were measured by three methods. The results obtained from the two methods which considered the series resistance were in close agreement with each other and from them barrier height (φ b ), ideality factor (n) and series resistance (R s ) were found to be 0.2045 eV , 2.877 and 14.556 KΩ respectively. By measuring the I-V characteristics in the temperature range of 85-136 K the electrical parameters were observed to have strong dependency on temperature. The increase of barrier height and decrease of ideality factor with increasing temperature is attributed to the existence of barrier height inhomogeneities in the silicide-semiconductor structure.

Abstract:Effects of an extra PdO layer in resistance-based hydrogen sensors are considered. P-type Si substrates were subjected to porous Si by electrochemical etching at room temperature. One category of samples has PdO layer in its structure while the other one does not. We have used electron-beam method for Pd deposition. Results show that when electron-beam technique is used for Pd deposition, existence of PdO layer will increase the range of sensors' operation up to 1% of hydrogen concentration. These samples will be saturated after 186sec-onds, while the samples without this layer can detect hydrogen up to 0.6% in 150 seconds response time.