Effect of thermal annealing on the electronic parameters of Al/p-Si/Cu double Schottky barrier heights

In this work, performance enhancements of a double Schottky rectifier diode with Cu contact on top of p-type Si and a back-side-Al contact due to an optimized thermal annealing process are reported. A decrease of the ideality factor for non-ohmic and ohmic Schottky contacts from 3.17 to 1.15 could be observed in conjunction with a barrier height reduction from 0.59 eV to 0.48 eV by thorough hydrofluoric acid treatment prior to annealing the sample for 15 min. at 450 degrees C in N2 atmosphere. Moreover, the barrier height and built-in voltage values decreased by increasing frequency in the ohmic contact structure. The results presented in this work demonstrate such ohmic contacts to be potential candidates for high current and low resistance Schottky diodes and applications.

Automated summary

This work reports on the performance enhancements of a double Schottky rectifier diode with Cu contact on top of p-type Si and a back-side-Al contact due to an optimized thermal annealing process. Thorough hydrofluoric acid treatment prior to annealing the sample for 15 min. at 450 degrees C in N2 atmosphere resulted in a decrease of the ideality factor and barrier height for non-ohmic and ohmic Schottky contacts. The results demonstrate the potential of these ohmic contacts for high current and low resistance Schottky diodes and applications.