Barrier reduction and current transport mechanism in Pt/n-InP Schottky diodes using atomic layer deposited ZnO interlayer

Modification of interface properties in Pt/n-InP Schottky contacts with atomic layer deposited ZnO interlayer (IL) (5 and 10 nm) has been carried out and the electrical properties were investigated using current–voltage (I–V) and capacitance–voltage (C–V) techniques. The insertion of ZnO IL in the Pt/n-InP interface reduced the effective barrier height. The barrier heights from C–V method were higher with respect to those from I–V method. The interface state density for 5 nm thick ZnO was higher than that for 10 nm thick ZnO. The barrier heights according to thermionic field emission model showed much closer to those from C–V method. Surface passivation and interfacial dipole were suggested to modulate the Schottky barrier at the Pt/ZnO/n-InP interface.