Properties of nitrogen-implanted p-type ZnO films grown on Si3N4/Si by radio-frequency magnetron sputtering

Abstract

An nitrogen-implanted p-type ZnO film has been grown on a Si substrate buffered with Si3N4 using radio-frequency magnetron sputtering. The Si3N4 buffer layer can effectively improve film stoichiometry and reduce the formation of oxygen vacancies compared to ZnO on Si. The electrical properties of the p-type ZnO films implanted with 5×1012–1×1014 cm−2 N+ dose show a hole concentration of 5.0×1016–7.3×1017 cm−3, hole mobility of 2.51–6.02 cm2/V s, and resistivity of 10.11–15.3 Ω cm. The p-type ZnO films also showed an excellent crystallinity and a strong ultraviolet emission peak near 3.30 eV at room temperature. Moreover, as evidenced by extended x-ray absorption fine structure analysis, the local structure of the p-type ZnO films was changed due to the substitution of nitrogen ions for oxygen ions in p-type ZnO films. Our finding of p-type ZnO films grown on a Si3N4/Si substrate could provide a simple method to fabricate reproducible p-type ZnO films on silicon substrate for the development of large-scale optoelectronic integration device.

Influence of anneal atmosphere on ZnO-nanorod photoluminescent and morphological properties with self-powered photodetector performance

“…17 Nitrogen-doping (N-doping) was reported to induce p-type conductivity through the implantation of acceptor-type defects. [18][19][20] However, studies have since shown that N-doping compensates p-type behaviour by forming shallow donors rather than acceptors, consequently p-type ZnO is unlikely to form. [21][22][23][24][25] Point defects situated deep in the ZnO bandgap (E g ) give rise to photoluminescence (PL) referred to as deep-level emission (DLE) observed under excitation >E g .…”

“…However, a small bias is always present in the measurement system, as must be the case for previous self-powered photodetectors since non-zero dark currents are always measured. [15][16][17][18] Here, we report the effect of materials processing on the ZnO properties and on the performance of nanorod-based photodetector devices using a highly alkaline (pH 11) solution consisting of HMT, zinc nitrate, and ammonia to synthesise the ZnO nanorods. In the ZnO synthesis, HMT is reported to act as a pH buffer that gradually decomposes to supply ammonia and hydroxyl ions to the reaction (Eqs.…”

Optical properties and microstructure of 2.02-3.30 eV ZnCdO nanowires: Effect of thermal annealing

“…Indeed, several groups have reported the use of thermal annealing in the 500-800 C range to decrease the ohmic contact resistance to ZnO, 7 whereas others have used annealing as high as 850-900 C to increase the carrier mobility 8 or to activate p-type dopants. 9 Because of the low growth temperatures used for ZnCdO, which are in the 300-500 C range, 10,11 these post growth annealing processes are likely to induce structural, electrical, and optical changes in the alloys. These changes need to be accounted for and understood, especially for the case of ZnCdO, since Cd has a strong tendency to diffuse.…”

Dependence of the gas sensing properties of ZnO nanowires on their microstructure

“…1(c). The oxygen vacancies in the ZnO nanowires serve as electron donors to supply electrons to the conduction band of ZnO and make ZnO nanowires an n-type semiconductor [24]. The oxygen molecules on the ZnO surface adsorbed from the atmosphere capture electrons from the conduction band.…”