Effects of Ga_xZn_1−xO nanorods on the photoelectric properties of n-ZnO nanorods/p-GaN heterojunction light-emitting diodes

Abstract

A Ga-doped ZnO nanorod array has been synthesized on a p-GaN/Al2O3 substrate by a hydrothermal method at low temperature.

The Path of Gallium from Chemical Bath into ZnO Nanowires: Mechanisms of Formation and Incorporation

“…14,15 Conversely, Li et al observed no effect on the c-lattice parameter and a decrease in the mean diameter of ZnO NWs. 16 The pH value has not been reported in those three papers. In contrast, Pineda-Hernańdez et al and Saravanakumar et al investigated the spontaneous growth of ZnO nanostructures by CBD at a given pH of 12 following the addition of NaOH.…”

“…In particular, the doping efficiency of Ga into ZnO is much larger than its Al counterpart because the ionic radius of Ga 3+ is closer to the Zn 2+ radius than the Al 3+ radius, opening the way for higher doping levels in ZnO . The evolution of the structural morphology of ZnO NWs grown by CBD, when Ga­(NO 3 ) 3 is used as a chemical additive in the chemical bath, has been reported. − However, some of the findings are in apparent discrepancy because the critical parameters including the pH and Ga­(NO 3 ) 3 concentration in the chemical bath as well as the Ga content into the ZnO NWs have not been measured systematically, nor varied on a broad range, nor combined with theoretical thermodynamic simulations. Recently, Lim et al and Park et al showed a decrease in the c -lattice parameter of ZnO NWs and an increase in their mean diameter when the Ga­(NO 3 ) 3 concentration in the chemical bath was increased. , Conversely, Li et al observed no effect on the c -lattice parameter and a decrease in the mean diameter of ZnO NWs .…”

“…The evolution of the structural morphology of ZnO NWs grown by CBD, when Ga­(NO 3 ) 3 is used as a chemical additive in the chemical bath, has been reported. − However, some of the findings are in apparent discrepancy because the critical parameters including the pH and Ga­(NO 3 ) 3 concentration in the chemical bath as well as the Ga content into the ZnO NWs have not been measured systematically, nor varied on a broad range, nor combined with theoretical thermodynamic simulations. Recently, Lim et al and Park et al showed a decrease in the c -lattice parameter of ZnO NWs and an increase in their mean diameter when the Ga­(NO 3 ) 3 concentration in the chemical bath was increased. , Conversely, Li et al observed no effect on the c -lattice parameter and a decrease in the mean diameter of ZnO NWs . The pH value has not been reported in those three papers.…”

Improved electrical transport properties of an n-ZnO nanowire/p-diamond heterojunction

“… 12,13 However, in virtue of the deep acceptor impurity states, low solubility dopants and the self-compensation effect, the intrinsically n-type semiconductor ZnO is difficult to manufacture with a p–n homo-junction architecture for many electronic and optical devices. 14 Thus far, additional p-type substrate materials, for instance, Si, 15 Cu 2 O, 16 GaN, 17 graphene, 18 NiO, 7 B-doped diamond film (BDD) 19–22 and organic materials, 23 have been exploited as the candidate to replace p-type ZnO semiconductors for the fabrication of pn heterojunctions. Among them, the B-doped diamond film (bandgap 5.47 eV) is appropriate as a high-temperature p-type conductive material.…”

“…Cu 2 O, 16 GaN, 17 graphene, 18 NiO, 7 B-doped diamond lm (BDD) [19][20][21][22] and organic materials, 23 have been exploited as the candidate to replace p-type ZnO semiconductors for the fabrication of pn heterojunctions. Among them, the B-doped diamond lm (bandgap 5.47 eV) is appropriate as a hightemperature p-type conductive material.…”