Thickness Study of Ga₂O₃ Barrier Layer in p-Si/n-MgZnO:Er/Ga₂O₃/ZnO:In Diode

Abstract

The p-Si/n-MgZnO:Er/Ga2O3/ZnO:In diodes with different Ga2O3 thicknesses were fabricated through spray pyrolysis deposition at 450 °C with aqueous solutions containing magnesium nitrate, zinc acetate, erbium acetate, gallium nitrate, and indium nitrate precursors. The effects of Ga2O3 layer thickness on the diode properties were investigated. For the deposited films, a combined tiny hexagonal slices and small blocks surface morphology was characterized by scanning electron microscopy for all samples. Diodes were formed after In and Ag deposition on the back side and top side, respectively. The current-voltage characteristics and luminescence spectra are studied. With the increasing of Ga2O3 thickness, the diode forward bias resistance increases while the reverse biased dark current shows the decrease-increase characters. The Er ion corresponded green light emission was characterized for the diode under reverse biased breakdown condition. The increased luminescent intensity with low turn-on current behaviors was characterized by the diode with a Ga2O3 thickness of 4.9 nm. With the diode electrical and luminescence analysis, the effect of the Ga2O3 barrier layer on the diode was discussed. The Ga2O3 barrier layer improves performance for rare earth-related light-emitting devices.

Keywords

• gallium oxide
• magnesium zinc oxide
• erbium
• diode