Phosphorus doping and hydrogen passivation of donors and defects in silicon nanowires synthesized by laser ablation

Abstract

Phosphorus ͑P͒ doping was performed during the synthesis of silicon nanowires ͑SiNWs͒ by laser ablation. At least three types of signals were observed by electron spin resonance ͑ESR͒ at 4.2 K. Phosphorus doping into substitutional sites of crystalline Si in SiNWs was demonstrated by the detection of an ESR signal with a g value of 1.998, which corresponds to conduction electrons in crystalline Si, and by an energy-dispersive x-ray spectroscopy spectrum of the P K␣ line. The ESR results also revealed the presence of defects. These defects were partially passivated by hydrogen and oxygen atoms.

Growth, Thermodynamics, and Electrical Properties of Silicon Nanowires

“…196 An approach that in principle offers much better controllability of dopant type and density is to directly supply the dopant during growth. This can be done either by a coevaporation or coablation of Si and dopant in the case of MBE nanowire growth 65 or laser ablation, 80,197,198 respectively, or by supplying both Si and dopants in the form of gaseous precursors in the case of CVD nanowire growth. 199,200 The latter appears to be the most promising approach, and we will concentrate on gas phase doping in the following.…”

Codoping of boron and phosphorus in silicon nanowires synthesized by laser ablation

“…9,10 The study showed the states of dopant atoms in SiNWs such as bonding structures, sites, and electrical activities using micro-Raman scattering and electron spin resonance ͑ESR͒. 9,10 The results of our microRaman scattering measurements clearly showed the presence of boron ͑B͒ local vibrational peaks and Fano broadening of Si optical phonon peaks due to heavy B doping in SiNWs. 9 ESR measurements at 4.2 K showed the ESR signal of conduction electrons in phosphorus ͑P͒-doped SiNWs.…”

Phosphorus ion implantation in silicon nanocrystals embedded in SiO2

“…Then phosphorus ͑P͒ ions were doubly implanted with the doses ranging from 10 14 to 10 17 / cm 2 at energies of 100 and 200 keV to obtain nearly flat P impurity distribution in the depth direction, followed by thermal annealing of produced defects at 1000°C. PL at room temperature ͑RT͒ and ESR measurements at 4.2 K were performed before and after hydrogen atom treatment ͑HAT͒, [10][11][12] i.e., hydrogen passivation of remaining defects such as P b centers induced at the interface between SiNCs and the surrounding SiO 2 . HAT was done at 500°C which was found to be an optimum temperature for efficient elimination of the interface defects.…”