Mechanism of current transport in Schottky barrier diodes based on coarse-grained CdTe films

Abstract

The possibility of fabricating a Schottky barrier on Al-p-CdTe structures with the lowest density of surface states has been demonstrated and confirmed by the results obtained from the capacitance-voltage and photoelectric measurements of the potential barrier height. It has been established that, at different forward bias voltages, there are different exponential dependences of the electric current on the voltage, which are related to the changes in kinetic parameters of the base of the Al-p-CdTe-Mo structure. It has been shown that the Al-p-CdTe-Mo structure at a forward current and high illumination levels operates as an injection photodiode. This injection photodiode has a high current sensitivity. When the current is switched on in the reverse direction, after the complete coverage of the base of the structure by the space charge, electrons responsible for the charge transfer mechanism and noise characteristics of the structure are injected from the rear contact.