n-ZnO/p-GaN heterojunction light-emitting diodes featuring a buried polarization-induced tunneling junction

Abstract

n-ZnO/p-GaN heterojunction light-emitting diodes with a p-GaN/Al0.1Ga0.9N/n+-GaN polarization-induced tunneling junction (PITJ) were fabricated by metal-organic chemical vapor deposition. An intense and sharp ultraviolet emission centered at ∼396 nm was observed under forward bias. Compared with the n-ZnO/p-GaN reference diode without PITJ, the light intensity of the proposed diode is increased by ∼1.4-folds due to the improved current spreading. More importantly, the studied diode operates continuously for eight hours with the decay of only ∼3.5% under 20 mA, suggesting a remarkable operating stability. The results demonstrate the feasibility of using PITJ as hole injection layer for high-performance ZnO-based light-emitting devices.

Review of GaN Nanostructured Based Devices

“…Compared with the n-ZnO/p-GaN reference diode without PITJ, the light intensity of the proposed diode was increased by 1.4 folds due to the improved current spreading. More importantly, the studied diode operates continuously for eight hours with the decay of only 3.5% under 20 mA, suggesting a remarkable operating stability [88]. The study's results demonstrated the feasibility of using PITJ as hole injection layer for high performance ZnO based light emitting devices [88].…”

“…More importantly, the studied diode operates continuously for eight hours with the decay of only 3.5% under 20 mA, suggesting a remarkable operating stability [88]. The study's results demonstrated the feasibility of using PITJ as hole injection layer for high performance ZnO based light emitting devices [88]. The schematic diagram of the PITJ device is shown Figure 8 (a) [88].…”

“…The study's results demonstrated the feasibility of using PITJ as hole injection layer for high performance ZnO based light emitting devices [88]. The schematic diagram of the PITJ device is shown Figure 8 (a) [88]. The I-V characteristics of Au on n-ZnO, Ni/Au on p-GaN and In on n-GaN is shown in Figure 8 (b) [88].…”

“…Figure 7. SEM of NPSFC LED: (a) 300 nm, and (b) 600 nm trapezoidal structure [87] The designing and fabrication of n-ZnO/p-GaN heterojunction LEDs emitting diodes with a p-GaN/Al0.1Ga0.9N/n+-GaN polarization induced tunneling junction (PITJ) were reported by Li et al [88]. An intense and sharp ultraviolet emission centered at 396 nm was observed under forward bias.…”

“…The schematic diagram of the PITJ device is shown Figure 8 (a) [88]. The I-V characteristics of Au on n-ZnO, Ni/Au on p-GaN and In on n-GaN is shown in Figure 8 (b) [88]. The three linear curves shown in the figure reveal the good ohmic contacts of Au on ZnO, Au/Ni on p-GaN and In on n-GaN, which indicates the rectification behaviors arise from the heterojunctions [88].…”