Studies of current–voltage characteristics of nanocrystalline Al/(p)PbSe Schottky barrier junctions

Nanocrystalline lead selenide thin films are prepared by a chemical bath depostion method on glass substrates and characterized by XRD, SEM and TEM techniques. The Al/(p)PbSe Schottky device is fabricated on FTO substrates by depositing Al electrodes on the chemically prepared PbSe films which have been studied for their electrical properties. The I–V characteristics measured at different temperatures (300–340 K) show rectifying characteristics and are explained by thermionic emission theory. The ideality factor ‘n’ of the junctions has been observed to decrease from 6.13 to 5.30 and barrier height ϕb increases from 0.743 eV to 0.772 eV with increase in temperature. Series resistance calculated at room temperature for a typical Al/(p)PbSe junction in dark and under illumination is found to be 2273 Ω and 1081 Ω respectively. Further it is observed that series resistance shows decreasing trend with increase in temperature. Carrier concentration Na calculated from the C–V plot is found to be on the order of 1016 cm−3. The discrepancy between the barrier height obtained from C–V and I–V characteristics is analyzed.